Characterization of the Response of Superheated Droplet (Bubble) Detectors

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小波阻抗差 avo 反射英文

小波阻抗差avo 反射英文全文共3篇示例，供读者参考篇1Wave impedances are important parameters in wave mechanics and are crucial for understanding the behavior of waves when they encounter boundaries or interfaces. One commonly used wave impedance is the acoustic velocity impedance (AVO), which describes the ratio of the acoustic pressure to the acoustic velocity in a medium. AVO plays a crucial role in seismic exploration, where it helps in determining the contrasts in rock properties that can indicate the presence of hydrocarbons underground.In seismic exploration, one key concept that is frequently encountered is the reflection coefficient, which describes the ratio of the reflected wave to the incident wave when a wave encounters a boundary. The reflection coefficient is dependent on the wave impedances of the two media on either side of the boundary and can be used to predict the behavior of waves at interfaces.One important application of wave impedances and reflection coefficients is in seismic inversion, where the goal is to infer the properties of the subsurface rocks from seismic data. By analyzing the reflections of seismic waves at interfaces and their velocities and amplitudes, geophysicists can reconstruct the subsurface structure and identify potential oil and gas reservoirs.Additionally, wave impedances play a crucial role in reservoir characterization, where they are used to assess rock properties such as porosity, permeability, and lithology. By analyzing the variations in wave impedances and reflection coefficients across a reservoir, geoscientists can better understand the reservoir properties and improve their reservoir modeling and production strategies.In conclusion, wave impedances, especially AVO and reflection coefficients, are essential tools in wave mechanics and seismic exploration. By understanding these parameters and their relationships, geophysicists and geoscientists can better interpret seismic data, characterize reservoirs, and improve their understanding of the subsurface geology.篇2A Study on Small Wave Impedance Discrepancy and AVO ReflectionIntroductionIn exploration geophysics, the amplitude variation with offset (AVO) technique is widely used to evaluate subsurface properties by analyzing the reflection amplitudes of seismic waves at different offsets. The AVO response is affected by various factors such as lithology, fluid content, and the presence of small-scale heterogeneities. One important factor that influences the AVO response is the small wave impedance discrepancy, which refers to the difference in wave impedance between neighboring rock layers.Small Wave Impedance DiscrepancyWave impedance is a property that characterizes the ability of a medium to transmit seismic waves. It is defined as the product of the density and seismic velocity of the medium. When seismic waves encounter a boundary between two rock layers with different wave impedances, part of the wave energy is reflected back to the surface, leading to amplitude variations in the recorded seismic data. The small wave impedance discrepancy refers to the difference in wave impedance betweenadjacent rock layers that is too small to be resolved by conventional seismic data processing techniques.AVO ReflectionThe AVO response of a rock layer is determined by its angle-dependent reflectivity, which is influenced by the small wave impedance discrepancy. When the wave impedance discrepancy between two adjacent rock layers is small, the AVO response becomes more sensitive to changes in the angle of incidence of the seismic waves. This sensitivity is characterized by the AVO anomaly, which is a deviation from the expected AVO response based on the properties of the rock layers.Case StudyTo investigate the relationship between small wave impedance discrepancy and AVO reflection, a case study was conducted in a sedimentary basin with alternating layers of sandstone and shale. Seismic data were acquired using a marine seismic survey and processed to estimate the wave impedances of the rock layers. The AVO response was then analyzed to identify any anomalies that could be attributed to the small wave impedance discrepancy.ResultsThe analysis of the seismic data revealed that the small wave impedance discrepancy between the sandstone and shale layers was indeed influencing the AVO response. In areas where the wave impedance discrepancy was significant, the AVO anomaly was more pronounced, indicating a higher sensitivity of the reflectivity to changes in the angle of incidence. This result highlights the importance of incorporating the small wave impedance discrepancy in AVO analysis to improve the accuracy of subsurface property estimation.ConclusionThe study on small wave impedance discrepancy and AVO reflection provides valuable insights into the factors that influence the AVO response in seismic data. By considering the wave impedance discrepancy between adjacent rock layers, geophysicists can better interpret the AVO anomalies and improve the characterization of subsurface properties. Further research is needed to explore the implications of small wave impedance discrepancy on other seismic attributes and develop more advanced processing techniques to account for this phenomenon.篇3Small Wave Impedance Difference AVO ReflectionIntroductionThe study of small wave impedance difference AVO reflection has significant implications for the exploration and production of oil and gas reservoirs. AVO, or amplitude versus offset, refers to the variation in seismic amplitudes with offset and is a key tool in seismic data analysis. By analyzing the small wave impedance difference AVO reflection, geophysicists can gain valuable insights into subsurface rock properties, fluid content, and potential hydrocarbon reserves.Small Wave Impedance DifferenceImpedance is the product of the velocity and density of a material and is a fundamental property that influences the reflection of seismic waves. In the context of small wave impedance difference AVO reflection, geophysicists are interested in the variation in impedance between different layers of rock. By analyzing the impedance contrast at small scales, researchers can derive information about the subsurface geology with high precision.AVO ReflectionAVO reflection refers to the changes in seismic amplitudes as a function of offset. In the context of small wave impedance difference AVO reflection, geophysicists are interested in the relationship between the amplitude of the reflected waves and the impedance differences between adjacent layers. The AVO response can be characterized by various attributes, such as the AVO gradient, intercept, and curvature, which provide valuable information about the subsurface properties.Applications in Oil and Gas ExplorationThe study of small wave impedance difference AVO reflection has numerous applications in oil and gas exploration. By analyzing the AVO response, geophysicists can identify potential hydrocarbon traps, estimate reservoir properties, and improve the accuracy of seismic imaging. The detection of small-scale impedance variations can also help in delineating subtle structural features and predicting lithology changes.Case Study: North SeaIn the North Sea region, the study of small wave impedance difference AVO reflection has played a crucial role in the exploration and development of oil and gas fields. By integrating AVO analysis with well data and seismic interpretation, geoscientists have been able to improve reservoircharacterization and reduce exploration risks. The identification of subtle stratigraphic traps and fault compartments has led to the discovery of significant reserves in the area.Future DirectionsAs technology advances, the study of small wave impedance difference AVO reflection is expected to become even more sophisticated. With the development of advanced seismic imaging techniques and machine learning algorithms, geophysicists will be able to extract valuable insights from the seismic data with greater accuracy and efficiency. The integration of multi-component seismic data and rock physics modeling will further enhance the understanding of subsurface properties and improve reservoir prediction.ConclusionIn conclusion, the study of small wave impedance difference AVO reflection is a valuable tool in oil and gas exploration. By analyzing the variation in impedance at small scales and correlating it with the AVO response, geophysicists can gain valuable insights into subsurface properties and improve reservoir characterization. With continued research and technological advancements, the field of small wave impedancedifference AVO reflection is poised to make significant contributions to the oil and gas industry in the years to come.。

西方批评理论考试

一、New criticism二、Formalism三、Reader-response theoryWhat Do You Think?At its most basic level, reader response criticism considers readers' reactions to literature as vital to interpreting the meaning of the text. However, reader-response criticism can take a number of different approaches. A critic deploying reader-response theory can use a psychoanalytic lens, a feminists lens, or even a structuralist lens. What these different lenses have in common when using a reader response approach is they maintain "...that what a text is cannot be separated from what it does" (Tyson 154).Tyson explains that "...reader-response theorists share two beliefs: 1) that the role of the reader cannot be omitted from our understanding of literature and 2) that readers do not passively consume the meaning presented to them by an objective literary text; rather they actively make the meaning they find in literature" (154). In this way, reader-response theory shares common ground with some of the deconstructionists discussed in the Post-structural area when they talk about "the death of the author," or her displacement as the (author)itarian figure in the text.四、StructuralismLinguistic RootsThe structuralist school emerges from theories of language and linguistics, and it looks for underlying elements in culture and literature that can be connected so that critics can develop general conclusions about the individual works and the systems from which they emerge. In fact, structuralism maintains that "...practically everything we do that is specifically human is expressed in language" (Richter 809). Structuralists believe that these language symbols extend far beyond written or oral communication.For example, codes that represent all sorts of things permeate everything we do: "the performance of music requires complex notation...our economic life rests upon the exchange of labor and goods for symbols, such as cash, checks, stock, and certificates...social life depends on the meaningful gestures and signals of 'body language' and revolves around the exchange of small, symbolic favors: drinks, parties, dinners" (Richter 809).Patterns and ExperienceStructuralists assert that, since language exists in patterns, certain underlying elements are common to all human experiences. Structuralists believe we can observe these experiences through patterns: "...if you examine the physical structures of all buildings built in urban America in 1850 to discover the underlying principles that govern their composition, for example, principles of mechanical construction or of artistic form..." you are using a structuralist lens (Tyson 197).Moreover, "you are also engaged in structuralist activity if you examine the structure of a single building to discover how its composition demonstrates underlying principles of a structural system. In the first example...you're generating a structural system of classification; in the second, you're demonstrating that an individual item belongs to a particular structural class" (Tyson 197). Structuralism in Literary TheoryStructuralism is used in literary theory, for example, "...if you examine the structure of a large number of short stories to discover the underlying principles that govern their composition...principles of narrative progression...or of characterization...you are also engaged instructuralist activity if you describe the structure of a single literary work to discover how its composition demonstrates the underlying principles of a given structural system" (Tyson 197-198).Northrop Frye, however, takes a different approach to structuralism by exploring ways in which genres of Western literature fall into his four mythoi (also see Jungian criticism in the Freudian Literary Criticism resource):1.theory of modes, or historical criticism (tragic, comic, and thematic);2.theory of symbols, or ethical criticism (literal/descriptive, formal, mythical, andanagogic);3.theory of myths, or archetypal criticism (comedy, romance, tragedy, irony/satire);4.theory of genres, or rhetorical criticism (epos, prose, drama, lyric) (Tyson 240). Peirce and SaussureTwo important theorists form the framework (hah) of structuralism: Charles Sanders Peirce and Ferdinand de Saussure. Peirce gave structuralism three important ideas for analyzing the sign systems that permeate and define our experiences:1."iconic signs, in which the signifier resembles the thing signified (such as the stickfigures on washroom doors that signify 'Men' or 'Women';2.indexes, in which the signifier is a reliable indicator of the presence of the signified(like fire and smoke);3.true symbols, in which the signifier's relation to the thing signified is completelyarbitrary and conventional [just as the sound /kat/ or the written word cat areconventional signs for the familiar feline]" (Richter 810).These elements become very important when we move into deconstruction in the Postmodernism resource. Peirce also influenced the semiotic school of structuralist theory that uses sign systems. Sign SystemsThe discipline of semiotics plays an important role in structuralist literary theory and cultural studies. Semioticians "...appl[y] structuralist insights to the study of...sign systems...a non-linguistic object or behavior...that can be analyzed as if it were a language" (Tyson 205). Specifically, "...semiotics examines the ways non-linguistic objects and behaviors 'tell' us something.For example, the picture of the reclining blond beauty in the skin-tight, black velvet dress on the billboard...'tells' us that those who drink this whiskey (presumably male) will be attractive to...beautiful women like the one displayed here" (Tyson 205). Lastly, Richter states, "semiotics takes off from Peirce - for whom language is one of numerous sign systems - and structuralism takes off from Saussure, for whom language was the sign system par excellence"五、Poststructuralism/ DeconstructionThe Center Cannot HoldThis approach concerns itself with the ways and places where systems, frameworks, definitions, and certainties break down. Post-structuralism maintains that frameworks and systems, for example the structuralist systems explained in the Structuralist area, are merely fictitious constructs and that they cannot be trusted to develop meaning or to give order. In fact, the very act of seeking order or a singular Truth (with a capital T) is absurd because there exists no unified truth.Post-structuralism holds that there are many truths, that frameworks must bleed, and that structures must become unstable or decentered. Moreover, post-structuralism is also concernedwith the power structures or hegemonies and power and how these elements contribute to and/or maintain structures to enforce hierarchy. Therefore, post-structural theory carries implications far beyond literary criticism.What Does Your Meaning Mean?By questioning the process of developing meaning, post-structural theory strikes at the very heart of philosophy and reality and throws knowledge making into what Jacques Derrida called "freeplay": "The concept of centered structure...is contradictorily coherent...the concept of centered structure is in fact the concept of a freeplay which is constituted upon a fundamental immobility and a reassuring certitude, which is itself beyond the reach of the freeplay" (qtd. in Richter, 878-879).Derrida first posited these ideas in 1966 at Johns Hopkins University, when he delivered ―Structure, Sign, and Play in the Discourse of the Human Sciences‖: "Perhaps something has occurred in the history of the concept of structure that could be called an 'event,' if this loaded word did not entail a meaning which it is precisely the function of structural-or structuralist-thought to reduce or to suspect. But let me use the term ―event‖ anyway, employing it with caution and as if in quotation marks. In this sense, this event will have the exterior form of a rupture and a redoubling‖ (qtd. in Richter, 878). In his presentation, Derrida challenged structuralism's most basic ideas.Can Language Do That?Post-structural theory can be tied to a move against Modernist/Enlightenment ideas (philosophers: Immanuel Kant, Réne Descartes, John Locke, etc.) and Western religious beliefs (neo-Platonism, Catholicism, etc.). An early pioneer of this resistance was philosopher Friedrich Nietzsche. In his essay, ―On Truth and Lies in an Extra-moral Sense‖ (1873), Nietzsc he rejects even the very basis of our knowledge making, language, as a reliable system of communication: ―The various languages, juxtaposed, show that words are never concerned with truth, never with adequate expression...‖ (248).Below is an example, adapted from the Tyson text, of some language freeplay and a simple form of deconstruction:Time (noun) flies (verb) like an arrow (adverb clause) = Time passes quickly.Time (verb) flies (object) like an arrow (adverb clause) = Get out your stopwatch and time the speed of flies as you would time an arrow's flight.Time flies (noun) like (verb) an arrow (object) = Time flies are fond of arrows (or at least of one particular arrow).So, post-structuralists assert that if we cannot trust language systems to convey truth, the very bases of truth are unreliable and the universe - or at least the universe we have constructed - becomes unraveled or de-centered. Nietzsche uses language slip as a base to move into the slip and shift of truth as a whole: ―What is truth? …truths are an illusion about which it has been forgotten that they are illusions...‖ (On Truth and Lies 250).This returns us to the discussion in the Structuralist area regarding signs, signifiers, and signified. Essentially, post-structuralism holds that we cannot trust the sign = signifier + signified formula, that there is a breakdown of certainty between sign/signifier, which leaves language systems hopelessly inadequate for relaying meaning so that we are (returning to Derrida) in eternal freeplay or instability.What's Left?Important to note, however, is that deconstruction is not just about tearing down - this is a common misconception. Derrida, in "Signature Event Context," addressed this limited view of post-structural theory: "Deconstruction cannot limit or proceed immediately to a neutralization: it must…practice an overturning of the classical opposition and a general displacement of the system. It is only on this condition that deconstruction will provide itself the means with which to intervene in the field of oppositions that it criticizes, which is also a field of nondiscursive forces" (328).Derrida reminds us that through deconstruction we can identify the in-betweens and the marginalized to begin interstitial knowledge building.六、Postmodernism七、PostcolonialismHistory is Written by the VictorsPost-colonial criticism is similar to cultural studies, but it assumes a unique perspective on literature and politics that warrants a separate discussion. Specifically, post-colonial critics are concerned with literature produced by colonial powers and works produced by those who were/are colonized. Post-colonial theory looks at issues of power, economics, politics, religion, and culture and how these elements work in relation to colonial hegemony (western colonizers controlling the colonized).Therefore, a post-colonial critic might be interested in works such as Daniel Defoe's Robinson Crusoe where colonial "...ideology [is] manifest in Crusoe's colonialist attitude toward the land upon which he's shipwrecked and toward the black man he 'colonizes' and names Friday" (Tyson 377). In addition, post-colonial theory might point out that "...despite Heart of Darkness's (Joseph Conrad) obvious anti-colonist agenda, the novel points to the colonized population as the standard of savagery to which Europeans are contrasted" (Tyson 375). Post-colonial criticism also takes the form of literature composed by authors that critique Euro-centric hegemony.A Unique Perspective on EmpireSeminal post-colonial writers such as Nigerian author Chinua Achebe and Kenyan author Ngugi wa Thiong'o have written a number of stories recounting the suffering of colonized people. For example, in Things Fall Apart, Achebe details the strife and devastation that occurred when British colonists began moving inland from the Nigerian coast.Rather than glorifying the exploratory nature of European colonists as they expanded their sphere of influence, Achebe narrates the destructive events that led to the death and enslavement of thousands of Nigerians when the British imposed their Imperial government. In turn, Achebe points out the negative effects (and shifting ideas of identity and culture) caused by the imposition of western religion and economics on Nigerians during colonial rule.Power, Hegemony, and LiteraturePost-colonial criticism also questions the role of the western literary canon and western history as dominant forms of knowledge making. The terms "first-world," "second world," "third world" and "fourth world" nations are critiqued by post-colonial critics because they reinforce the dominant positions of western cultures populating first world status. This critique includes the literary canon and histories written from the perspective of first-world cultures. So, for example, a post-colonial critic might question the works included in "the canon" because the canon does not contain works by authors outside western culture.Moreover, the authors included in the canon often reinforce colonial hegemonic ideology, such as Joseph Conrad's Heart of Darkness. Western critics might consider Heart of Darkness an effective critique of colonial behavior. But post-colonial theorists and authors might disagree with this perspective: "...as Chinua Achebe observes, the novel's condemnation of European is based on a definition of Africans as savages: beneath their veneer of civilization, the Europeans are, the novel tells us, as barbaric as the Africans. And indeed, Achebe notes, the novel portrays Africans as a pre-historic mass of frenzied, howling, incomprehensible barbarians..."八、New HistoricismIt's All Relative...This school, influenced by structuralist and post-structuralist theories, seeks to reconnect a work with the time period in which it was produced and identify it with the cultural and political movements of the time (Michel Foucault's concept of épistème). New Historicism assumes that every work is a product of the historic moment that created it. Specifically, New Historicism is "...a practice that has developed out of contemporary theory, particularly the structuralist realization that all human systems are symbolic and subject to the rules of language, and the deconstructive realization that there is no way of positioning oneself as an observer outside the closed circle of textuality" (Richter 1205).A helpful way of considering New Historical theory, Tyson explains, is to think about the retelling of history itself: "...questions asked by traditional historians and by new historicists are quite different...traditional historians ask, 'What happened?' and 'What does the event tell us about history?' In contrast, new historicists ask, 'How has the event been interpreted?' and 'What do the interpretations tell us about the interpreters?'" (278). So New Historicism resists the notion that "...history is a series of events that have a linear, causal relationship: event A caused event B; eventB caused event C; and so on" (Tyson 278).New historicists do not believe that we can look at history objectively, but rather that we interpret events as products of our time and culture and that "...we don't have clear access to any but the most basic facts of history...our understanding of what such facts mean...is...strictly a matter of interpretation, not fact" (279). Moreover, New Historicism holds that we are hopelessly subjective interpreters of what we observe.九、Feminism(1960s-present)S/heFeminist criticism is concerned with "...the ways in which literature (and other cultural productions) reinforce or undermine the economic, political, social, and psychological oppression of women" (Tyson). This school of theory looks at how aspects of our culture are inherently patriarchal (male dominated) and "...this critique strives to expose the explicit and implicit misogyny in male writing about women" (Richter 1346). This misogyny, Tyson reminds us, can extend into diverse areas of our culture: "Perhaps the most chilling example...is found in the world of modern medicine, where drugs prescribed for both sexes often have been tested on male subjects only" (83).Feminist criticism is also concerned with less obvious forms of marginalization such as the exclusion of women writers from the traditional literary canon: "...unless the critical or historical point of view is feminist, there is a tendency to under-represent the contribution of women writers" (Tyson 82-83).Common Space in Feminist TheoriesThough a number of different approaches exist in feminist criticism, there exist some areas of commonality. This list is excerpted from Tyson:1.Women are oppressed by patriarchy economically, politically, socially, andpsychologically; patriarchal ideology is the primary means by which they are keptso2.In every domain where patriarchy reigns, woman is other: she is marginalized,defined only by her difference from male norms and values3.All of western (Anglo-European) civilization is deeply rooted in patriarchal ideology,for example, in the biblical portrayal of Eve as the origin of sin and death in theworld4.While biology determines our sex (male or female), culture determines our gender(masculine or feminine)5.All feminist activity, including feminist theory and literary criticism, has as itsultimate goal to change the world by prompting gender equality6.Gender issues play a part in every aspect of human production and experience,including the production and experience of literature, whether we are consciouslyaware of these issues or not (91).Feminist criticism has, in many ways, followed what some theorists call the three waves of feminism:1.First Wave Feminism - late 1700s-early 1900's: writers like Mary Wollstonecraft (AVindication of the Rights of Women, 1792) highlight the inequalities between thesexes. Activists like Susan B. Anthony and Victoria Woodhull contribute to thewomen's suffrage movement, which leads to National Universal Suffrage in 1920with the passing of the Nineteenth Amendment2.Second Wave Feminism - early 1960s-late 1970s: building on more equal workingconditions necessary in America during World War II, movements such as theNational Organization for Women (NOW), formed in 1966, cohere feminist politicalactivism. Writers like Simone de Beauvoir (Le deuxième sexe, 1972) and ElaineShowalter established the groundwork for the dissemination of feminist theoriesdove-tailed with the American Civil Rights movementThird Wave Feminism- early 1990s-present: resisting the perceived essentialist (over generalized, over simplified) ideologies and a white, heterosexual, middle class focus of second wave feminism, third wave feminism borrows from post-structural and contemporary gender and race theories (see below) to expand on marginalized populations' experiences. Writers like Alice Walker work to "...reconcile it [feminism] with the concerns of the black community...[and] the survival and wholeness of her people, men and women both, and for the promotion of dialog and community as well as for the valorization of women and of all the varieties of work women perform".十、MarxismBased on the theories of Karl Marx (and so influenced by philosopher Georg Wilhelm Friedrich Hegel), this school concerns itself with class differences, economic and otherwise, as well as the implications and complications of the capitalist system: "Marxism attempts to reveal the ways in which our socioeconomic system is the ultimate source of our experience" (Tyson 277). Theorists working in the Marxist tradition, therefore, are interested in answering the overarching question, whom does it [the work, the effort, the policy, the road, etc.] benefit? The elite? The middle class? And Marxists critics are also interested in how the lower or working classes are oppressed - in everyday life and in literature.The Material DialecticThe Marxist school follows a process of thinking called the material dialectic. This belief system maintains that "...what drives historical change are the material realities of the economic base of society, rather than the ideological superstructure of politics, law, philosophy, religion, and art that is built upon that economic base" (Richter 1088).Marx asserts that "...stable societies develop sites of resistance: contradictions build into the social system that ultimately lead to social revolution and the development of a new society upon the old" (1088). This cycle of contradiction, tension, and revolution must continue: there will always be conflict between the upper, middle, and lower (working) classes and this conflict will be reflected in literature and other forms of expression - art, music, movies, etc.Though a staggering number of different nuances exist within this school of literary theory, Marxist critics generally work in areas covered by the following questions.十一、OtherGender Studies and Queer Theory (1970s-present)Gender(s), Power, and MarginalizationGender studies and queer theory explore issues of sexuality, power, and marginalized populations (woman as other) in literature and culture. Much of the work in gender studies and queer theory, while influenced by feminist criticism, emerges from post-structural interest in fragmented, de-centered knowledge building (Nietzsche, Derrida, Foucault), language (the breakdown of sign-signifier), and psychoanalysis (Lacan).A primary concern in gender studies and queer theory is the manner in which gender and sexuality is discussed: "Effective as this work [feminism] was in changing what teachers taught and what the students read, there was a sense on the part of some feminist critics that...it was still the old game that was being played, when what it needed was a new game entirely. The argument posed was that in order to counter patriarchy, it was necessary not merely to think about new texts, but to think about them in radically new ways" (Richter 1432).Therefore, a critic working in gender studies and queer theory might even be uncomfortable with the binary established by many feminist scholars between masculine and feminine: "Cixous (following Derrida in Of Grammatology) sets up a series of binary oppositions (active/passive, sun/moon...father/mother, logos/pathos). Each pair can be analyzed as a hierarchy in which the former term represents the positive and masculine and the latter the negative and feminine principle" (Richter 1433-1434).In-BetweensMany critics working with gender and queer theory are interested in the breakdown of binaries such as male and female, the in-betweens (also following Derrida's interstitial knowledge building). For example, gender studies and queer theory maintains that cultural definitions of sexuality and what it means to be male and female are in flux: "...the distinction between "masculine" and "feminine" activities and behavior is constantly changing, so that women who wear baseball caps and fatigues...can be perceived as more piquantly sexy by some heterosexual men than those women who wear white frocks and gloves and look down demurely". Moreover, Richter reminds us that as we learn more about our genetic structure, the biology of male/female becomes increasingly complex and murky: "even the physical dualism of sexual genetic structures and bodily parts breaks down when one considers those instances-XXYsyndromes, natural sexual bimorphisms, as well as surgical transsexuals - that defy attempts at binary classification".十二、精神分析Psychoanalytic Criticism (1930s-present)Sigmund FreudPsychoanalytic criticism builds on Freudian theories of psychology. While we don't have the room here to discuss all of Freud's work, a general overview is necessary to explain psychoanalytic literary criticism.The Unconscious, the Desires, and the DefensesFreud began his psychoanalytic work in the 1880s while attempting to treat behavioral disorders in his Viennese patients. He dubbed the disorders 'hysteria' and began treating them by listening to his patients talk through their problems. Based on this work, Freud asserted that people's behavior is affected by their unconscious: "...the notion that human beings are motivated, even driven, by desires, fears, needs, and conflicts of which they are unaware..." (Tyson 14-15).Freud believed that our unconscious was influenced by childhood events. Freud organized these events into developmental stages involving relationships with parents and drives of desire and pleasure where children focus "...on different parts of the body...starting with the mouth...shifting to the oral, anal, and phallic phases..." (Richter 1015). These stages reflect base levels of desire, but they also involve fear of loss (loss of genitals, loss of affection from parents, loss of life) and repression: "...the expunging from consciousness of these unhappy psychological events" (Tyson 15).Tyson reminds us, however, that "...repression doesn't eliminate our painful experiences and emotions...we unconsciously behave in ways that will allow us to 'play out'...our conflicted feelings about the painful experiences and emotions we repress" (15). To keep all of this conflict buried in our unconscious, Freud argued that we develop defenses: selective perception, selective memory, denial, displacement, projection, regression, fear of intimacy, and fear of death, among others.Id, Ego, and SuperegoFreud maintained that our desires and our unconscious conflicts give rise to three areas of the mind that wrestle for dominance as we grow from infancy, to childhood, to adulthood: ∙id - "...the location of the drives" or libido∙ego - "...one of the major defenses against the power of the drives..." and home of the defenses listed above∙superego - the area of the unconscious that houses judgement (of self and others) and "...which begins to form during childhood as a result of the Oedipus complex" (Richter 1015-1016)Oedipus ComplexFreud believed that the Oedipus complex was "...one of the most powerfully determinative elements in the growth of the child" (Richter 1016). Essentially, the Oedipus complex involves children's need for their parents and the conflict that arises as children mature and realize they are not the absolute focus of their mother's attention: "the Oedipus complex begins in a late phase of infantile sexuality, between the child's third and sixth year, and it takes a different form in males than it does in females" (Richter 1016).Freud argued that both boys and girls wish to possess their mothers, but as they grow older "...they begin to sense that their claim to exclusive attention is thwarted by the mother's attention to the。

德育英文翻译

Situationism and Confucian Virtue EthicsDeborah S. MowerAccepted: 11 October 2011 /Published online: 9 November 2011Springer Science+Business Media B.V. 2011Abstract Situationist research in social psychology focuses on the situational factors that influence behavior. Doris and Harman argue that this research has powerful implications for ethics, and virtue ethics in particular. First, they claim that situationist research presents an empirical challenge to the moral psychology presumed within virtue ethics. Second, they argue that situationist research supports a theoretical challenge to virtue ethics as a foundation for ethical behavior and moral development. I offer a response from moral psychology using an interpretation of Xunzi—a Confucian virtue ethicist from the Classical period. This Confucian account serves as a foil to the situationist critique in that it uncovers many problematic ontological and normative assumptions at work in this debate regarding the prediction and explanation of behavior, psychological posits, moral development, and moral education. Xunzi‘s account of virtue ethics not only responds to the situationist empirical challenge by uncovering problematic assumptions about moral psychology, but also demonstrates that it is not a separate empirical hypothesis. Further, Xunzi‘s virtue ethic responds to the theoretical challenge by offering a new account of moral development and a ground for ethical norms that fully attends to situational features while upholding robust character traits.Keywords Situationism . Confucian . Virtueethics . Moraldevelopment . Xunzi . Character traits . Moralpsychology . Ritual . Doris . Harman1 Introduction 1Situationist research in social psychology focuses on the situational factors that influence behavior. 2 Doris and Harman argue that this research has powerful implications for ethics, and virtue ethics in particular. First, they claim that situationist research presents an empirical challenge to the moral psychology presumed within virtue ethics. Second, they argue that situationist research supports a theoretical challenge to virtue ethics as a foundation for ethical behavior and moral development. Virtue ethicists did not take such challenges lightly, and a vast literature developed in response. Many responses address the conception of character or virtue assumed by Harman and Doris, while others target the implications drawn from and the quality of situationist research. Doris refined the situationist challenges in his recent book Lack of Character and argued that ―divestingethical reflection of an empirically discredited psychology of character will facilitate emotional, evaluative, and deliberative habits that are more defensible, more sensitive, and more conducive to ethically desirable behavior‖ (2002, p. 2). The debate rages on at near impasse, both sides fully entrenched.Unsurprisingly, the debate is framed via Western conceptions of character and virtue; 3 after all, the protagonists are Western scholars embroiled over the implications of psychological research for modern ethical theory. In contrast, I offer a response from moral psychology using a Confucian conception of virtue ethics. Xunzi is an early Confucian philosopher whois very aware of situational effects on behavior, and builds this awareness into his account of moral development and program of moral education. I suggest that Xunzi holds an―embeddedness model‖ of moral development, 4 in which deliberation focused on and embedded in the determinative features of situations is the normative ground for ethics andthe apex of moral development. Consequently, one project of this paper is to present and argue for this interpretation of moral development in Xunzi‘s account.Secondly, I argue that this account serves as a lens to critique key ontological and normative assumptions about moral psychology and moral development within the arguments posed by the situationists Harman and Doris. In a sense, Doris and I share the same project: we each want to divest virtue ethics of problematic assumptions and then address the implications of rejecting those assumptions for moral education. However, we part company in the end: my project is to divest Harman and Doris of their problematic assumptions using an interpretation of Xunzi‘s model of moral development. Although my argument stems from an account of Confucian virtue ethics, the scope of this paper is quite broad in that it not only deflates the situationist challenges, but it also invites a revision of any account of virtue ethics that relies on these unwarranted and problematic assumptions. 5 Finally, I argue that Xunzi‘s account offers a unique response to the situationist challenges and a new avenue to conceive of virtue ethical moral psychology and moral education. Xunzi‘s accountrespondstothesituationistempiricalchallengebyuncoveringproblematicassumptions about moral psychology, and to the theoretical challenge by offering a new account of moral development that fully attends to situational features. What is so unique and promising about Xunzi‘s account is that it not only provides a normative ground for deliberative situational embeddedness without making the normative and ontological assumptions that plague situationism (and indeed which, situationists charge, plague other accounts of virtue ethics), butalsooffersawaytomoveforwardbyputtingsituationistresearchfromsocialpsychologyinthe service of detailing a Xunzian account of virtue ethics.2 The Challenges of SituationismDoris and Harman mount their empirical challenge to Western accounts of virtue ethics by critiquing globalism: an account of moral psychology committed to the theses that virtue or character traits are stable, consistent, and integrated. On a dispositionalist account, virtues or character traits such as courageousness or honesty produce behavior because they are psychological dispositions to behave in specified ways. Doris explains that character traits are stable when they are ―reliably manifested in trait-relevant behaviors over iterated trials of similar trait-relevant eliciting conditions‖ (2002, p. 22). For example, if I am honest, I would return extra money to a cashier whether (a) in Starbucks, (b) in the grocery store, or (c) at the bank. He defines character traits as consistent when they are ―relia bly manifested in trait- relevant behavior across a diversity of trait-relevant eliciting conditions that may vary widely in their conduciveness to the manifestation of the trait in question‖ (Doris 2002, p. 22). For example, if I am honest, I would (a) return money to the cashier upon receiving extra change, (b) report all my income to the IRS, and (c) register for all philosophy conferences attended. Character traits are integrated when ―the occurrence of a trait with a particular evaluative valence is probabilistically related to the occurrence of other traits with similar evaluative valences‖ (Doris 2002, p. 22). For example, if I think my friend is trustworthy, I may also assume that she is honest. Doris explains that to attribute a virtue is to asser t a conditional: ―If a person possesses a trait, that person will exhibit trait-relevant behavior in trait-relevant eliciting conditions with markedly above chance probability p‖ (2002, p. 19). However, this honesty-attribution does not merely express a correlational claim that my friend will display honesty in honesty-eliciting situations, but that the reason she returns the money is becauseshe is honest; honesty, as a psychological trait, is causally efficacious for or productive of her behavior. Attributing virtues to others not only helps to explain their behavior, but it also allows for fairly reliable predictions. When a cashier accidentally returns an extra $20 in change to my honest friend, I can predict with some confidence that she will return the money despite the fact that she recently lost her job.Doris explains that stability, consistency, and integration are the three key theses of globalism. However, he notes that they are three separate theses: stability and consistency are theses about the nature of traits, while integration is a thesis about personality and trait organization (2002, p. 23). My interests in this paper focus on the first two theses of globalism: the characterization of virtues as stable and consistent psychological traits. For Doris and Harman, the lack of stability and consistency in character traits provides strong evidence against virtue ethics, whether dispositionalist or intellectualist. On a disposition- alist account, as described above, character traits are robust when they are stable through time, consistent across situation types, causally efficaious, and allow for reliable predictions and explanations of behavior. On an intellectualist account, virtue is the correct perceptionof and response to the morally salient features of a situation (e.g., perceiving a situation as one which requires honesty, and then performing the honest action, such as returning the extra change to the cashier). 6 Doris claims that the attempt to explain virtue as a perceptual capacity or sensitivity still requires that such traits be stable and consistent in order to be connected to behavior. Consequently, he holds that the same arguments can be leveled against both accounts of virtue ethics.Although a virtue ethicist might point to regular exhibitions of honest behavior asevidence of the psychological trait or virtue of honesty, Harman and Doris begin the empirical challenge by arguing that there is a competing hypothesis: the behavioral regularity we observe may be due to the stability and consistency of situations rather than stable and consistent character traits (Doris 2002, p. 26; Harman 1999, p. 317). Situationist research, Harman argues, shows that ―aspects of a particular situation can be importantto how a person acts in ways that ordinary people do not normally appreciate, leadingthem to attribute certain distinctive actions to an agent‘s distinctive character ratherthan to subtle aspects of the situation‖ (2003, p. 91). Situationist research illustrates the myriad ways that situations produce or elicit behavior, indicated most clearly by changesin behavior as a consequence of situational variation. As Doris notes, ―the problem is notthat substantial situational factors have substantial effects on what people do, but that seemingly insubstantial situational factors have substantial effects on what people do‖(2002, p. 29). Given this, Harman concludes that ―despite appearances, there is no empirical support for the existence of character traits‖ (1999, p. 330, my emphasi s). For Harman, the fact that researchers can manipulate behavior by varying situational features demonstrates that situational regularity, not robust psychological character traits, yields behavioral regularity. 7Doris adopts a more temperate position: given that situationist research casts seriousdoubts on virtues as globally stable and consistent psychological traits, the empirical evidence favors situational regularity over robust character traits as a behavioral explanation (2002, p. 26). Although Harman abandons character traits, Doris suggests thata modified conception of character traits may have some explanatory value. 8 In contrast torobust or global character traits which are stable through time and consistent across a wide variety of situations, Doris proposes that character traits may be local or limited to narrowly specified situations. He explains that the disposition for ―battlefield physical courage‖would yield courageous behavior whenever one engaged in a physical contest on a battlefield, but not during storms on the high seas, while being tortured, or upon stepping into a den of snakes (2002, p. 62). The fact that one does not behave courageously when confronted with snakes or when tortured is not a mark of instability or inconsistency; rather, it is simply not a disposition that is productive of behavior in such cases. Although Doris doubts the empirical adequacy of global character traits, he thinks that local character traits may offer an explanatory alternative more compatible with situationist research. However, local character traits offer no solace to virtue ethicists. Doris explains that ―local traits are not likely to produce the patterns of behavior expected on broad trait categories like‗compassionate‘ or ‗courageous:‘ even seemingly insignificant variations in situation may ‗tap‘ different dispositions, effecting inconsistent behavior‖ (1998, p. 507). Local character traits, subject to situational fluctuations, are of no use to accounts of virtue ethics that depend on the situational invariance of global character traits.The empirical challenge to robust character traits supports Harman‘s sweeping theoretical challenge to virtue ethics as a foundation for ethical behavior and moral development. He arguesthatanempiricallysuspectpsychologicalmodelofcharactertraitsundercutsanaccountof moral behavior defined in terms of virtue. As Harman notes, ―if we know that there is no such thing as a character trait and we know that virtue would require having character traits, how can we aim at becoming a virtuous agent?‖ (2000, p. 224). If virtues do not exist, then the moral ideals assumed by virtue ethics are untenable, and the attempt to develop virtue and character is a waste of time and effort. 10 Harman holds no punches.Harman‘s challenge, if it succeeds, goes for the jugular, but Doris‘s challenge is no less formidable. Doris charges that ―the approach to moral psychology suggested by situationism enjoys certain advantages…as a foundation for normative thought‖ (1998, p. 505). He suggests that rejecting the assumption of robust global character traits may yield more ethical behavior—a counter-intuitive consequence to many virtue ethicists. Rather than getting into situations likely to elicit unethical behavior and mistakenly relying on the ―strength‖ of one‘s character, he argues that situationism suggests attention to the features and avoidance of enticing but sinful situations. For example, quaffing wine while attending a private dinner at the home of a handsome and flirtatious colleague while his spouse is away is a situation loaded with sinfully enticing features (Doris 1998, p. 516). Relying on one‘s character is foolhardy. Doris argues that ―the way to get things right more often…is by attending to the determinat ive features of situations,‖ and that ―the implication of this is that our duties may be surprisingly complex, involving…a sort of ‗cognitive responsibility‘to attend, in our deliberations, to the determinative features of situations‖ (1998, p. 517). His challenge, if it succeeds, undercuts virtue ethics by offering a new foundation for ethical behavior and moral development. In the next few sections, I introduce Xunzi and the importance of ritual, explain how his account of moral development and program of moral education develops attention to situational features as a moral action, and show how his virtue ethic can withstand these empirical and theoretical challenges.3 Xunzi and the Importance of RitualAlthough Confucius (551–479 BCE) is as well known as Aristotle (384–322 BCE), many Western scholars are less familiar with the philosophers that follow Confucius. Mencius (372–289 BCE) and Xunzi (approx. 310–215 BCE) 11 are philosophers of the Classic period of Confucianism. The Classic period is delineated by the Warring States period (479–221 BCE), in which a number of independent feudal states vied for supremacy. The Classic period ended in 221 BCE, when the state of Qin conquered all to create the first unifiedstate and dynasty in China.As was common for many philosophers of his time, Xunzi served as a political figure, holding posts in several states. In each, he expounded Confucian views on morality, education, and political policy. He also was a leading figure at the prestigious Jixia Academy, akin to a modern ―think-tank‖ for the intellectuals of the day, in which he cameinto contact with proponents of all the major Sinitic schools of philosophical thought (suchas Daoism and Mohism). In contrast to texts like the Analects and the Mencius, which capture aphoristic quotations or record conversations, the Xunzi is a treatise composed of essays on specific topics. In this text, Xunzi develops focused arguments against other schools of thought and other interpretations of Confucianism, and builds a systematic argument with integrated theses on metaphysics and human nature, moral education,political philosophy, philosophy of language, action theory, and aesthetics. 12Mencius and Xunzi offered competing interpretations of Confucianism, and Xunzi‘s emphasis on the importance of ritual is often seen as direct response to Mencius and his views on human nature. Mencius famously claimed that human nature was ―good,‖ or that the components of morality are innate. (For a modern Western parallel: one might claim that an empathic ability is innate.) Xunzi is often credited with the contrasting claim that human nature is ―bad.‖ However, his position is not that human nature is evil, but that it is crude, unformed, and contains possibilities for both good and evil: to claim that human nature is ―good‖ is to accountforonlypartofournature.XunzithoughtMencius‘sviewsweredangerouslysimplistic because they implied that morality could develop naturally and minimized the importance of moral education. For Xunzi, moral education is necessary to shape the myriad innate capacities of human nature: without moral education, individuals will not develop into moral persons and society will devolve into chaos (akin to a Hobbesian state of nature).For Xunzi, ritual forms an ineliminable part of moral education: rituals provide modelsfor individuals and establish order and structure in society. 13 Although Western theoristsmay not be accustomed to thinking in terms of ritual, rituals are ubiquitous. For example,the context of listening to a speech or lecture is a common modern American ritual. Without ever pausing to consider how to act while attending a lecture, one knows not only what to do, but also what to expect; one knows how to behave (e.g., that one sits in the chair anddoes not stand and dance on it, that one does not speak unless it is necessary and then onlyat a whisper to a colleague), which establishes expectations for how others will behave aswell (e.g., that one should not interrupt the speaker). This implicit knowledge that we all share coordinates our collective action (e.g., comments and concerns of audience memberswill be addressed in a question and answer session after the lecture, each person will speakin turn and not in a group shouting match, etc.), and our collective action is ordered and orderly (i.e., we each attain what we desire—to hear the lecture—because we engaged inthe ritual properly). Although this is just one example, rituals pervade our lives. As Tunotes, Confucians conceive of ritual w ithin ―personal conduct, social relations, political organizations, and religious behavior….[Ritual] includes virtually all aspects of human culture: psychological, social, and religious‖ (1972, p. 198).In addition to providing models for behavior, ritual s shape one‘s desires, emotions, moods, andmotivations,aswellasestablishinterpretiveframeworksforunderstandingevents.Because Xunzi holds that human nature contains myriad possibilities for good or ill, ritual simultaneously nurtures one‘s good tendencies (e.g., desires, emotions, moods, and motivations) while minimizing the negative. For example, disgust and fear are common and natural responses when viewing a corpse. But while these responses are natural, they are not appropriate at a funeral; revulsion distracts one from paying tribute to the departed, and, typically, does not provide much comfort to the departed‘s beloved. Xunzi holds that ritual can support and give proper shape to one‘s natural responses so that they are appropriate. He explains:the standard practice of funeral rites is that one changes the appearance of the corpseby gradually adding more ornamentation, one moves the corpse gradually furtherway, and over a long time one gradually returns to one‘s regular routine. Thus, theway that death works is that if one does not ornament the dead, then one will come tofeel disgust at them, and if one feels disgust, then one will not feel sad. If one keepsthem close, then one will become casual with them, and if one becomes casual withthem, then one will grow tired of them. If one grows tired of them, then one willforget one‘s place, and if one forgets one‘s place, then one will not be respectful.(Hutton Ch.19: 290–300) 14Much like the medieval European practice of covering a corpse in flowers to mask the smell, or the modern Western practice of arranging hair, applying makeup, and dressing the corpse in her ―Sunday best,‖ the rituals surrounding Chinese ornamentation in funeral rites ensure that there is no diminution or distortion of natural emotions that should arise when regarding the deceased. Rather than cultivating disgust, funeral rituals provide a supportive context to nurture positive emotional responses such as sympathy, love, and respect. 15 Further, the funeral is structured in order to remember and honor the departed: eulogies, short stories, or moments of silence are common ways to honor the deceased and to comfort the living. Because funeral rituals are structured in such a way to elicit positive emotional responses and to provide avenues for remembrance and consolation, they provide interpretive frameworks by making aspects of events salient; although one may be overcome with personal grief, the structure of the funeral (the placement of the family at the front, speeches made by family members, prayers offered in consolation and support to family members, etc.) makes the family‘s grief salient and redirects one‘s attention accordingly. In addition to providing models for proper behavior, rituals provide models for proper thought by shaping one‘s emotional responses, expectations, interpretations, etc.For Xunzi, rituals are comprehensive and detailed models for our behavior, emotions,and thoughts, and are thereby necessary for moral education and maintaining social order.He expl ains that if one‘s intentions and thoughtsaccord with ritual, they will be ordered and effective. If they do not accord with ritual,they will be disorderly and unproductive. If your meals, clothing, dwelling, andactivities accord with ritual, they will be congenial and well-regulated. If they do notaccord with ritual, you will encounter dangers and illnesses. If your countenance,bearing, movements, and stride accord with ritual, they will be graceful. If they donot accord with ritual, they will be barbaric, obtuse, perverse, vulgar, and unruly.(Hutton Ch. 2: 35–50) 16As comprehensive models for clothing, food, bearing, countenance, emotion, mood, and thought, rituals provide standards for and regulate our individual and collective action. Ritual pervades all aspects and all details of our lives by shaping our emotions, moods, and desires, framing our thoughts, interpretations, and perceptions, structuring our behavior, and mediating our interactions with others. By taking the raw material afforded within human nature (our innate capacities and natural responses) and shaping it, ritual develops individuals into social beingscapableofengagingwitheachother,promotingsocialorder,andseekingpersonalmoral development. 17 Consequently, the study and practice of ritual is a necessary component to maintain social order and to develop individuals through moral education.。

An overview of ocean renewable energy in China 中国海洋资源开发回顾

An overview of ocean renewable energy in ChinaRenewable and Sustainable Energy ReviewsFacing great pressure of economic growth and energy crisis, China pays much attention to the renewable energy. An overview of policy and legislation of renewable energy as well as status of development of renewable energy in China was given in this article. By analysis, the authors believe that ocean energy is a necessary addition to existent renewable energy to meet the energy demand of the areas and islands where traditional forms of energy are not applicable and it is of great importance in adjusting energy structure of China. In the article, resources distribution and technology status of tidal energy, wave energy, marine current energy, ocean thermal energy and salinity gradient energy in China was reviewed, and assessment and advices were given for each category. Some suggestions for future development of ocean energy were also given.Design pressure distributions on the hull of the FLOW wave energy converterThis paper presents a procedure to calculate the design pressure distributions on the hull of a wave energy converter (WEC). Design pressures are the maximum pressure values that the device is expected to experience during its operational life time. The procedure is applied to the prototype under development by Martifer Energy (FLOW—Future Life in Ocean Waves).A boundary integral method is used to solve the hydrodynamic problem. The hydrodynamic pressures are combined with the hydrostatic ones and the internal pressures of the large ballast tanks. The first step consists of validating the numerical results of motions by comparison with measured experimental data obtained with a scaled model of the WEC. The numerical model is tuned by adjusting the damping of the device rotational motions and the equivalent damping and stiffness of the power take-off system. The pressure distributions are calculated for all irregular sea states representative of the Portuguese Pilot Zone where the prototype will be installed and a long term distribution method is used to calculate the expected maximum pressures on the hull corresponding to the 100-year return period.海波流能量转换器压力分散设计Development of an adaptive disturbance rejection system for the rapidly deployable stable platform–part 1: Mathematical modeling and open loop response 海面作业平台系统的稳定性保证：数学建模与开环响应模拟实验A Rapidly Deployable Stable Platform (RDSP) concept was investigated at Florida Atlantic University in response to military and civilian needs for ocean platforms with improved sea-keeping characteristics. The RDSP is designed to have enhanced sea-keeping abilities through the combination of a novel hull and thruster design coupled with active control. The RDSP is comprised of a catamaran that attaches via a hinge to a spar, enabling it to transit like a trimaran and then reconfigure so that the spar lifts the catamaran out of the water, creating a stable spar platform. The focus of this research is the mathematical modeling, simulation, and response characterization of the RDSP to provide a foundation for controller design, testing, and tuning. The mathematical model includes a detailed representation of residual drag, friction drag, added mass, hydrostatic and hydrodynamic pressure, and control actuator dynamics. Validation has been performed by comparing the simulation predicted motions of the RDSP operating in waves to the measured motions of the 1/10th scale prototype measured at sea. Resulting from this paper is an empirical assessment of the response characteristics of the RDSP that quantifies the performance under extreme conditions and provides a solid basis for controller development and testing.Combined use of dimensional analysis and modern experimental design methodologies in hydrodynamics experiments海洋工程设计的多维度分析与现代化的实验化设计与验证的方法In this paper, a combined use of dimensional analysis (DA) and modern statistical design of experiment (DOE) methodologies is proposed for a hydrodynamics experiment where there are a large number of variables. While DA is well-known, DOE is still unfamiliar to most ocean engineers although it has been shown to be useful in many engineering and non-engineering applications. To introduce and illustrate the method, a study concerning the thrust of a propeller is considered. Fourteen variables are involved in the problem and after dimensional analysis this reduces to 11 dimensionless parameters. Then, a two-level fractional factorial design was used to screen out parameters that do not significantly contribute to explaining the dependent dimensionless parameter. With the remaining five statistically significant dimensionless parameters, various response surface methodologies (RSM) were used to obtain a functional relationship between the dependent dimensionless thrust coefficient, and the five dimensionless parameters. The final model was found to be of reasonable accuracy when tested against results not used to develop the model. The methodologies presented in the paper can be similarly applied to systems with a large number of control variables to systematically derive approximate mathematical models to predict the responses of the system economically and accurately.Progress toward autonomous ocean sampling networks海洋实验与勘测的自动取样网络化系统的设计进程The goals of the Autonomous Ocean Sampling Network (AOSN) are reviewed and progress toward those goals is assessed based on results of recent, major field experiments. Major milestones include the automated control of multiple, mobile sensors for weeks using spatial coverage metrics and the transition from engineering a reliable data stream to managing the complexities of decision-making based on the data and the possibilities of timely feedback.Non-uniform adaptive vertical grids for 3D numerical ocean modelsOcean Modelling采用垂直化网格表示的的三维数字化海洋模型海洋建模学报A new strategy for the vertical gridding in terrain-following 3D ocean models is presented here. The vertical grid adaptivity is partially given by a vertical diffusion equation for the vertical layer positions, with diffusivities being proportional to shear, stratification and distance from the boundaries. In the horizontal, the grid can be smoothed with respect to z-levels, grid layer slope and density. Lagrangian tendency of the grid movement is supported. The adaptive terrain-following grid can be set to be an Eulerian–Lagrangian grid, a hybrid σ–ρ or σ–z grid and combinations of these with great flexibility. With this, internal flow structures such as thermoclines can be well resolved and followed by the grid. A set of idealised examples is presented in the paper, which show that the introduced adaptive grid strategy reduces pressure gradient errors and numerical mixing significantly. The grid adaption strategy is easy to implement in various types of terrain-following ocean models. The idealised examples give evidence that the adaptive grids can improve realistic, long-term simulations of stratified seas while keeping the advantages of terrain-following coordinates.Procedures for offline grid nesting in regional ocean models海岸离散测绘网布局点与区域海洋模型图绘制仿真步骤与过程One-way offline nesting of a primitive-equation regional ocean numerical model (ROMS) is investigated, with special attention to the boundary forcing file creation process. The model has a modified open boundary condition which minimises false wave reflections, and is optimised to utilise high-frequency boundary updates. The model configuration features a previously computed solution which supplies boundary forcing data to an interior domain with an increased grid resolution. At the open boundaries of the interior grid (the child) the topography is matched to that of the outer grid (the parent), over a narrow transition region. A correction is applied to the normal baroclinic and barotropic velocities at the open boundaries of the child to ensure volume conservation. It is shown that these steps, together with a carefully constructed interpolation of the parent data, lead to a high-quality child solution, with minimal artifacts such as persistent rim currents and wave reflections at the boundaries.Development of a Coupled Ocean–Atmosphere–Wave–Sediment Transport (COAWST) Modeling SystemUnderstanding the processes responsible for coastal change is important for managing our coastal resources, both natural and economic. The current scientific understanding of coastal sediment transport and geology suggests that examining coastal processes at regional scales can lead to significant insight into how the coastal zone evolves. To better identify the significant processes affecting our coastlines and how those processes create coastal change we developed a Coupled Ocean–Atmosphere–Wave–Sediment Transport (COAWST) Modeling System, which is comprised of the Model Coupling Toolkit to exchange data fields between the ocean model ROMS, the atmosphere model WRF, the wave model SWAN, and the sediment capabilities of the Community Sediment Transport Model. This formulation builds upon previous developments by coupling the atmospheric model to the ocean and wave models, providing one-way grid refinement in the ocean model, one-way grid refinement in the wave model, and coupling on refined levels. Herein we describe the modeling components and the data fields exchanged. The modeling system is used to identify model sensitivity by exchanging prognostic variable fields between different model components during an application to simulate Hurricane Isabel during September 2003. Results identify that hurricane intensity is extremely sensitive to sea surface temperature. Intensity is reduced when coupled to the ocean model although the coupling provides a more realistic simulation of the sea surface temperature. Coupling of the ocean to the atmosphere also results in decreased boundary layer stress and coupling of the waves to the atmosphere results in increased bottom stress. Wave results are sensitive to both ocean and atmospheric coupling due to wave–current interactions with the ocean and wave growth from the atmosphere wind stress. Sediment resuspension at regional scale during the hurricane is controlled by shelf width and wave propagation during hurricane approach.Contact dynamics of two floating cable-connected bodiesWe consider two ship-like bodies connected by six cables and excited by waves. The cables might be under tension, or they might be slack, thus forming a unilateral system generating possible impacts. The impact forces can reach 20,000 kN and are able to cause damage to a ship. In order to avoid such large impact forces, anti-shock buffers might be adopted but good buffer design requires knowledge of the impact forces. We have evaluated these using multi-body theory with unilateral contacts in combination with classical ship dynamics, which allows modeling of the contact dynamics of two floating bodies in an ocean. Based on an optimization algorithm a method using an artificial neural network (NNW) has been developed to determine the combination of possible constraints at each step. The results of a numerical example compare reasonably well with experiments. We have thus established a theoretical basis for further buffer design.Joint modelling of wave spectral parameters for extreme sea statesCharacterising the dependence between extremes of wave spectral parameters such as significant wave height (H S) and spectral peak period (T P) is important in understanding extreme ocean environments andin the design and assessment of marine structures. For example, it is known that mean values of wave periods tend to increase with increasing storm intensity. Here we seek to characterise joint dependence in a straightforward manner, accessible to the ocean engineering community, using a statistically sound approach.Many methods of multivariate extreme value analyses are based on models which assume implicitly that in some joint tail region each parameter is either independent of or asymptotically dependent on other parameters; yet in reality the dependence structure in general is neither of these. The underpinning assumption of multivariate regular variation restricts these methods to estimation of joint regions in which all parameters are extreme; but regions where only a subset of parameters are extreme can be equally important for design. The conditional approach of Heffernan and Tawn (2004), similar in spirit to that of Haver (1985) but with better theoretical foundation, overcomes these difficulties.We use the conditional approach to characterise the dependence structure of H S and T P. The key elements of the procedure are: (1) marginal modelling for all parameters, (2) transformation of data to a common standard Gumbel marginal form, (3) modelling dependence between data for extremes of pairs of parameters using a form of regression, (4) simulation of long return periods to estimate joint extremes. We demonstrate the approach in application to measured and hindcast data from the Northern North Sea, the Gulf of Mexico and the North West Shelf of Australia. We also illustrate the use of data re-sampling techniques such as bootstrapping to estimate the uncertainty in marginal and dependence models and accommodate this uncertainty in extreme quantile estimation.We discuss the current approach in the context of other approaches to multivariate extreme value estimation popular in the ocean engineering community.极端海洋多外力因素环境的综合作用仿真Robust diving control of an AUVMobile systems traveling through a complex environment present major difficulties in determining accurate dynamic models. Autonomous underwater vehicle motion in ocean conditions requires investigation of new control solutions that guarantee robustness against external parameter uncertainty.A diving-control design, based on Lyapunov theory and back-stepping techniques, is proposed and verified. Using adaptive and switching schemes, the control system is able to meet the required robustness. The results of the control system are theoretically proven and simulations are developed to demonstrate the performance of the solutions proposed.移动式潜水器的鲁棒控制Transient behavior of towed cable systems during ship turning maneuversThe dynamic behavior of a towed cable system that results from the tow ship changing course from a straight-tow trajectory to one involving steady circular turning at a constant radius is examined. For large-radius ship turns, the vehicle trajectory and vehicle depth assumed, monotonically and exponentially, the large-radius steady-state turning solution of Chapman [Chapman, D.A., 1984. The towed cable behavior during ship turning manoeuvers. Ocean Engineering 11, 327–361]. For small-radius ship turns, the vehicle trajectory initially followed a corkscrew pattern with the vehicle depth oscillating about and eventually decaying to the steady-state turning solution of Chapman (1984). The change between monotonic and oscillatory behavior in the time history of the vehicle depth was well defined and offered an alternate measure to Chapman's (1984) critical radius for the transition point between large-radius and small-radius behavior. For steady circular turning in the presence of current, there was no longer a steady-state turning solution. Instead, the vehicle depth oscillated with amplitude that was a function of the ship-turning radius and the ship speed. The dynamics of a single 360° turn and a 180° U-turn are discussed in terms of the transients of the steady turning maneuver. For a single 360°large-radius ship turn, the behavior was marked by the vehicle dropping to the steady-state turning depth predicted by Chapman (1984) and then rising back to the initial, straight-tow equilibrium depth once the turn was completed. For small ship-turning radius, the vehicle dropped to a depth corresponding to the first trough of the oscillatory time series of the steady turning maneuver before returning to the straight-tow equilibrium depth once the turn was completed. For some ship-turning radii, this resulted in a maximum vehicle depth that was greater than the steady-state turning depth. For a 180°turn and ship-turning radius less than the length of the tow cable, the vehicle never reached the steady-state turning depth.海洋勘测船的光缆稳定性与海波振动影响传输On the structure of Langmuir turbulenceThe Stokes drift induced by surface waves distorts turbulence in the wind-driven mixed layer of the ocean, leading to the development of streamwise vortices, or Langmuir circulations, on a wide range of scales. We investigate the structure of the resulting Langmuir turbulence, and contrast it with the structure of shear turbulence, using rapid distortion theory (RDT) and kinematic simulation of turbulence. Firstly, these linear models show clearly why elongated streamwise vortices are produced in Langmuir turbulence, when Stokes drift tilts and stretches vertical vorticity into horizontal vorticity, whereas elongated streaky structures in streamwise velocity fluctuations (u) are produced in shear turbulence, because there is a cancellation in the streamwise vorticity equation and instead it is vertical vorticity that is amplified. Secondly, we develop scaling arguments, illustrated by analysing data from LES, thatindicate that Langmuir turbulence is generated when the deformation of the turbulence by mean shear is much weaker than the deformation by the Stokes drift. These scalings motivate a quantitative RDT model of Langmuir turbulence that accounts for deformation of turbulence by Stokes drift and blocking by theair–sea interface that is shown to yield profiles of the velocity variances in good agreement with LES. The physical picture that emerges, at least in the LES, is as follows. Early in the life cycle of a Langmuir eddy initial turbulent disturbances of vertical vorticity are amplified algebraically by the Stokes drift into elongated streamwise vortices, the Langmuir eddies. The turbulence is thus in a neartwo-component state, with suppressed and . Near the surface, over a depth of order the integral length scale of the turbulence, the vertical velocity (w) is brought to zero by blocking of the air–sea interface. Since the turbulence is nearly two-component, this vertical energy is transferred intothe spanwise fluctuations, considerably enhancing at the interface. After a time of order half the eddy decorrelation time the nonlinear processes, such as distortion by the strain field of the surrounding eddies, arrest the deformation and the Langmuir eddy decays. Presumably, Langmuir turbulence then consists of a statistically steady state of such Langmuir eddies. The analysis then provides a dynamical connection between the flow structures in LES of Langmuir turbulence and the dominant balance between Stokes production and dissipation in the turbulent kinetic energy budget, found by previous authors.Effects of vertical variations of thickness diffusivity in an ocean general circulation model洋流循环模型The effects of a prescribed surface intensification of the thickness (and isopycnal) diffusivity on the solutions of an ocean general circulation model are documented. The model is the coarse resolution version of the ocean component of the National Center for Atmospheric Research (NCAR) Community Climate System Model version 3 (CCSM3). Guided by the results of Ferreira et al. (2005) [Ferreira, D., Marshall, J., Heimbach, P., 2005. Estimating eddy stresses by fitting dynamics to observations using a residual-mean ocean circulation model and its adjoint. J. Phys. Oceanogr. 35, 1891–1910.] we employ a vertical dependence of the diffusivity which varies with the stratification, N2, and is thus large in the upper ocean and small in the abyss. We experiment with vertical variations of diffusivity which are as large as 4000 m2 s−1 within the surface diabatic layer, diminishing to 400 m2 s−1 or so by a depth of 2 km. The new solutions compare more favorably with the available observations than those of the control which uses a constant value of 800 m2 s−1 for both thickness and isopycnal diffusivities. These include an improved representation of the vertical structure and transport of the eddy-induced velocity in the upper-ocean North Pacific, a reduced warm bias in the upper ocean, including the equatorial Pacific, and improved southward heat transport in the low- to mid-latitude Southern Hemisphere. There is also a modest enhancement of abyssal stratification in the Southern Ocean.Using satellite altimetry to correct mean temperature and salinity fields derived from Argo floats in the ocean regions around AustraliaWe present results from a suite of methods using in situ temperature and salinity data, and satellitealtimetric observations to obtain an enhanced set of mean fields of temperature, salinity (down to 2000-m depth) and steric height (0/2000 m) for a time-specific period (1992–2007). Firstly, the improved global sampling resulting from the introduction of the Argo program, enables a representative determination of the large-scale mean oceanic structure. However, shortcomings in the coverage remain. High variability western boundary current eddy fields, continental slope and shelf boundaries may all be below their optimal sampling requirements. We describe a simple method to supplement and improve standard spatial interpolation schemes and apply them to the available data within the waters surrounding Australia (100°E–180°W; 50°S–10°N). This region includes a major current system, the East Australian Current (EAC), complex topography, unique boundary currents such as the Leeuwin Current, and large ENSO related interannual variability in the southwest Pacific. We use satellite altimetry sea level anomalies (SLA) to directly correct sampling errors in in situ derived mean surface steric height and subsurface temperature and salinity fields. The surface correction is projected through the water column (using an empirical model) to modify the mean subsurface temperature and salinity fields. The errors inherent in all these calculations are examined. The spatial distribution of the barotropic–baroclinic balance is obtained for the region and a ‘baroclinic factor’ to convert the altimetry SLA into an equivalent in situ height is determined. The mean fields in the EAC region are compared with independent estimates on repeated XBT sections, a mooring array and full-depth CTD transects.海洋开发的航空与遥感大规模探测技术。

我们正在研究的各种英文表述

: glen_almond@W e are currently establishing methods to characterize porcine T-lymphocyte subpopulations for two different studies. One involves evaluation of the T cells in weaned pigs following vaccination with a novel adjuvant; the other focuses on the influence of stress on T-lymphocyte populations and immunity in young pigs. Lymphocyte trapping is associated with stress, and we plan to explore this perturbation of the immune system. In addition, other studies focus on understanding the physiological roles of tumor necrosis factor and prostaglandin-E prior to and after the initiation of luteolysis. We are examining the significance of vascular endothelial growth factor (VEGF) and hypoxia-induc ible factor (HIF) in porcine corpus luteum. We utilize RT-PCR and additional genomic methodologies to characterize the expression of the factors and their receptors. We anticipate that future studies will determine the respective signal transduction pathways and re-visit the influence of the cytokines and the immune system on corpus luteum function.Birkenheuer, Adam, DVM, PhDDepartment of Clinical SciencesNCSU College of V eterinary Medicine, Campus Box 84014700 Hillsborough StRaleigh, NC 27606Phone: (919) 513-8288E-mail: ajbirken@My research is focused on companion animal infectious diseases. Tick-transmitted protozoan parasites are emerging infectious diseases causing substantial morbidity and mortality worldwide. Our studies address discovery and characterization of novel pathogens, development of improved diagnostic assays, enhanced understanding of the epidemiology of tick-transmitted protozoan parasites, and identification of treatment strategies resulting in significantly improved survival rates.Breitschwerdt, Ed, DVMDepartment of Clinical SciencesNCSU College of V eterinary Medicine, Campus Box 84014700 Hillsborough StRaleigh, NC 27606Phone: (919) 919-513-8277E-mail: ed_breitschwerdt@My research interests are focused in the area of infectious diseases, with a particular emphasis on diagnostic, therapeutic, and immunopathologic aspects of zoonotic vector-transmitted bacterial and rickettsial diseases. The laboratory has contributed substantially to current understanding of Rickettsia rickettsii, Ehrlichia canis, and Bartonella vinsonii infection in dogs and Bartonella henselae in cats. We are currently capable of handling biosafety P3-level. It is increasingly obvious that vector borne pathogens contribute to a substantial quantity of animal and humandisease and suffering. In most instances the immunopathologic consequences of infection with one or simultaneous infection with multiple vector-transmitted infectious agents remains unknown. It is our goal to better define the clinical consequences of chronic infection with these organisms. Dean, Gregg, DVM, PhDDepartment of Molecular Biomedical SciencesNCSU College of V eterinary Medicine, Campus Box 84014700 Hillsborough StRaleigh, NC 27606Phone: (919) 513-2819E-mail: gregg_dean@My research focuses on the immunopathogenesis and prevention of human and feline immunodefic iency virus infection (HIV and FIV, respectively). FIV is a valuable model of human immunodeficiency virus infection in people and represents a significant health threat to the feline population world-wide. We are investigating the role of innate immune defects induced by HIV/FIV infection. These studies focus on the function of dendritic cells, natural killer cells, and Toll-like receptors in the immunopathogenesis of opportunistic infections during chronic retroviral infection. Ongoing vaccine studies seek to employ recombinant bacteria as vaccine vectors. We are evaluating recombinant Lactobacillus spp. engineered to express FIV/HIV Gag and consensus Env genes as a means to provide effective mucosal and systemic immune responses through oral immunization.Fogle, Jonathan, DVM, PhDDepartment of Population Health and PathobiologyNCSU College of V eterinary Medicine, Campus Box 84014700 Hillsborough StRaleigh, NC 27606Phone: (919) 513-6304E-mail: jonathan_fogle@Using the FIV model for HIV, we have shown that CD4+CD25+ T regulatory cells are constitutively activated and suppress CD4+CD25- T helper cell immune responses during the acute phase and chronic phase of infection. Results of our recent experiments indicate that CD4+CD25+ T regulatory cells suppress the CD8+ immune response during the acute and chronic stages of FIV infection. We are currently investigating the mechanism(s) of CD8+ cell mediated suppression and the intracellular signaling events that occur in CD8+ targets, following their interaction with activated CD4+CD25+ cell from FIV+ cats.Gilmour, Ian, BSc, PhDCardiopulmonary and Immunotoxicology BranchEnvironmental Public Health DivisionNational Health and Environmental Effects Research LaboratoryU.S. Environmental Protection AgencyResearch Triangle Park, NC 27711Phone: (919) 541-0015E-mail: Gilmour.Ian@We study the effect of air pollutant exposure on pulmonary immunity and subsequent development of allergic and infectious lung disease. Air pollutants are generated in the inhalation exposure facility at the EPA which has the capability to aerosolize simple gases and vapors, various particles including nanomaterials, as well as fossil fuel combustion emissions. The staff also operates mobile field sampling laboratories that collect size-fractionated particles from various locations across the country. The relative toxicity of various air pollutants are compared and then applied in animal models of asthma, influenza, or cardiac dysfunction. Parallel studies are conducted with in vitro systems in order to extrapolate between cell based and whole body responses for the purposes of predicting potential effects in humans. Hammerberg, Bruce, DVM, PhDDepartment of Population Health and PathobiologyNCSU College of V eterinary Medicine, Campus Box 84014700 Hillsborough StRaleigh, NC 27606Phone: (919) 513-7712E-mail: bruce_hammerberg@My current research expertise is in allergic diseases and nematode biology. Regarding allergic disease research, we have developed canine x murine heterohybridomas. One of these produces canine monoclonal IgE specific for a filarial nematode antigen. Another produces canine IgG antibody specific for canine IgE. Using these tools, I have developed mouse monoclonal antibodies against heat stable epitopes of canine IgE and have the opportunity to make canine monoclonal antibodies against canine IgE epitopes that will be useful in preventing allergic disease in the dog. The unlimited supply of canine IgE of known antigen specificity has directed my research toward characterizing inherited differences in mast cell function in the dog, and at this time I am investigating the role of stem cell factor in inherited canine atopic dermatitis.My work with filarial nematodes over the last 25 years has recently turned to investigating how fatty acid binding proteins function in nematode physiology.Havell, Edward, PhDDepartment of Population Health and PathobiologyNCSU College V eterinary Medicine, Campus Box 84014700 Hillsborough StRaleigh, NC 27606Phone: (919) 515-6184E-mail: ed_havell@The major objective of our research is to determine the roles that tumor necrosis factor (TNF), interferon-gamma (IFN-gamma) and host cells play in both innate and adaptive immunity toenteric bacterial pathogens. To study possible roles of cytokines and host cells in anti-bacterial resistance, specific inhibitors (e.g., anti-cytokine antibodies) that block the actions of a given cytokine or host cell are administered before or at progressive times during bacterial infection in mice. The subsequent course of infection is monitored to determine the effect of such treatment on bacterial pathogenesis. The long-range goal of our research is to acquire an understanding of how TNF, IFN-gamma, and host cells having anti-bacterial function interact in the defense of the host against bacterial pathogens. Studies are underway to develop a reproducible model of inflammatory bowel disease that will enable the study of the roles of cytokines and host cells in chronic inflammatory intestinal disease. Finally, we have generated an avirulent Listeria monocytogenes mutant that does not translocate from the intestinal lumen but induces very strong protective T cell-mediated anti-listerial immunity. We plan to evaluate this avirulent mutant as an orally administered vaccine platform to present secreted recombinant tuberculosis antigens to the intestinal immune system in order to elicit protective anti-TB T cell immunityHess, Paul, DVM, PhDDepartment of Clinical SciencesNCSU, College of V eterinary Medicine, Campus Box 84014700 Hillsborough StRaleigh, NC 27606Phone: (919) 513-6183E-mail: paul_hess@My principal interests are CD8-positive T cell immunology and immunotherapy. One focus of the laboratory is examining how the interaction of the MHC class I molecule and the T cell receptor can be manipulated to induce stable tolerance in animal models of autoimmunity and allotransplantation. The second focus is the discovery of new peptide epitopes in viral diseases. Lastly, we are investigating novel clinical predictors of chemotherapy-induced toxicity in the dog. Hudson, Lola C., DVM, PhDDepartment of Molecular Biomedical SciencesNCSU College V eterinary Medicine, Campus Box 84014700 Hillsborough StRaleigh, NC 27606Phone: (919) 513-6306E-mail: lola_hudson@Research in this laboratory focuses on the study of viral neuropathogenesis and blood-brain barrier (BBB) function. We are currently investigating feline immunodeficiency virus (FIV), which has divergent mechanisms of CNS entry, as a model for AIDS neuropathogenesis. We have developed an in vitro feline blood-brain barrier model system to determine the conditions under which immune cells in normal and FIV-infected animals are capable of penetrating the BBB. Additional studies focus on characteristics of attaching cells and mechanisms of attachment to the barrier such as up-regulation of specific adhesion molecules. Additionally, in vivo studies parallel in vitro studies with the aim of increasing detection of neural infection during the early stages ofdisease. We are currently focusing on various cognitive-motor behavioral tests in normal and infected cats to determine acute losses in neurologic function. Such tests can then be used to assess the efficacy of various therapeutics to delay or prevent CNS infection.Jones, Samuel L., DVM, PhDDepartment of Clinical SciencesNCSU College of V eterinary Medicine, Campus Box 84014700 Hillsborough StRaleigh NC 27606Phone: (919) 513-7722E-mail: sam_jones@My research interests focus on how inflammation is triggered and regulated and how inflammation contributes to the pathophysiology of diseases such as colitis, equine colic, sepsis, and endotoxemia. A primary objective of our work is to understand the cellular and molecular details of cell migration with a focus on the key innate immune cell, the neutrophil. We are particularly interested in how the signaling molecules protein kinase A, phosphatidylinositol 3-kinase, and p38 and the actin binding proteins MARCKS, V ASP, and L-plastin regulate the actin cytoskeleton, integrin function, and signaling during migration of neutrophils and other cell types. We use human and equine primary cells, cell lines, and in vivo models including mice and zebrafish for these studies. We are also studying how inflammation is triggered and how pro-inflammatory genes, particularly genes in the prostaglandin synthesis cascade that encode cyclooxygenase-2 and prostaglandin synthase-1, are upregulated in equine leukocytes. In collaborative work, we are studying the effects of neutrophils and inflammatory mediators on intestinal mucosal repair following ischemic injury that occurs in some forms of equine colic. Koci, Matt, PhDDepartment of Poultry ScienceNCSU Scott Hall, Campus Box 7608Raleigh, NC 27695Phone: (919) 515-5388E-mail: mdkoci@The overall focus of my research is to understand how the immune system responds to viral challenges. The majority of our work focuses on the innate aspects of host resistance to viral infection, particularly addressing how the innate immune system recognizes and responds to infection and thus can have profound affects on the adaptive immune response and ultimately the outcome of the infection. Understanding how stimulation of the innate immune system leads to different clinical outcomes is critical to understanding the genetic basis of disease resistance. Laster, Scott M., PhD- Immunology Program DirectorDepartment of MicrobiologyNCSU Gardner Hall, Campus Box 7615Raleigh, NC 27695Phone: (919) 515-7958E-mail: scott_laster@Research in my laboratory focuses on the anti-viral immune response. One aspect of this response currently under investigation is the apoptosis-inducing activity of tumor necrosis factor (TNF). TNF is a product of many cells, including macrophages and monocytes, and is released by these cells during infection. TNF is able to act in an anti-viral manner by causing the death of infected cells before virus replication is complete, thereby reducing the number of infectious virions that are produced. The apoptosis-inducing activity of TNF is selective for infected cells because these cells are unable to transcribe appropriate levels of NF-kB-dependent, anti-apoptotic gene products. The virus under investigation in my laboratory is the human adenovirus. While not a major human pathogen, the adenovirus represents an excellent model system for studies of molecular and cellular immunology. Recent studies from my laboratory suggest that adenovirus induces susceptibility to TNF by preventing the expression of a tyrosine or dual specificity phosphatase, leading us to propose that this phosphatase normally acts in an anti-apoptotic manner by inhibiting apoptotic signal transduction through the dephosphorylation of cytosolic phospholipase A2.Miller, Jennifer, PhDDepartment of MicrobiologyNCSU Gardner Hall, Campus Box 7615Raleigh, NC 27695Phone: (919) 515-7867E-mail: jen_miller@My research focuses on the interaction between the tick-borne spirochete Borrelia burgdorferi and the innate immune system. B. burgdorferi is the causative agent of Lyme disease, a multi-system disorder whose symptoms include the development of subacute arthritis within both a large joint of afflicted humans and the rear ankle joints of susceptible inbred mouse strains. This subacute arthritis is associated with the presence of B. burgdorferi within the joints. My laboratory utilizes tissue culture and mouse models to examine both the bacterial and host-derived mechanisms driving the induction of Lyme arthritis. We are currently focusing on a novel and previously unappreciated role for Type I interferon (IFN) in the development of severe Lyme arthritis. The goal of these studies is to identify additional bacterial effectors, innate immune components, and mechanistic pathways that drive both Type I IFN production and the development of Lyme arthritis.Nordone, Shila, PhDDepartment of Molecular Biomedical SciencesNCSU College V eterinary Medicine, Campus Box 84014700 Hillsborough StRaleigh, NC 27606Phone: (919) 515-7410E-mail: shila_nordone@My research involves studying the mechanisms and consequences of the molecular interactions between pathogenic organisms and the innate immune system. Pathogen-mediated modulation of innate immunity can dictate the pathological consequences of infection, the duration of survival of the pathogen in the host, and ultimately, the ability of the adaptive immune response to evolve and clear infection. At the center of my research is the role of Toll-like receptor (TLR) and Triggering Receptor Expressed on Myeloid Cells-1 (TREM-1) activation in pathogen-immune system interactions. We are currently engaged in the following research areas: 1) Modulation of TLR-mediated responses by HIV-1 infection and 2) TREM-1 mediated inflammation during canine sepsis. The overall aim of both areas of research is to increase our understanding of the basic mechanisms of pathogen-innate immune cell crosstalk and to identify new therapeutic targets for treating HIV and sepsis.Olivry, Thierry, DrV et, PhDDepartment of Clinical SciencesNCSU, College of V eterinary Medicine, Campus Box 84014700 Hillsborough StRaleigh, NC 27606Phone: (919) 513-6276E-mail: thierry_olivry@My principal research interests involve investigating the pathogenesis and therapy of canine atopic dermatitis and autoimmune skin diseases. Current projects on atopic dermatitis include clinical trials on the pharmacotherapy of this disease, modeling skin lesions experimentally, researching novel methods for immunotherapy as well as investigating the genetics of this trait in West Highland White Terriers. My research on autoimmune skin diseases involves the characterization of clinical signs, histopathology and immunological aspects of novel pathological entities of dogs, cats and horses. Additionally, we are investigating the autoantibody response in the blistering disease pemphigus foliaceus in dogs.Selgrade, Mary Jane, PhDImmunotoxicology BranchU.S. Environmental Protection AgencyResearch Triangle Park, NC 27711Phone: (919) 541-1821E-mail: selgrade.maryjane@My research interests center around the interactions between xenobiotic compounds (ambient and indoor air pollutants) and the immune system and consequent effects on susceptibility to infectious and allergic disease. The laboratory has developed several infectivity and allergy models in laboratory rodents. The focus is to understand the effects that exposure to environmental agents may have on both local and systemic immune responses, the underlying mechanisms associated with these effects, and the consequent impact on susceptibility to disease.Sherry, Barbara, PhDDepartment of Molecular Biomedical SciencesNCSU College V eterinary Medicine, Campus Box 84014700 Hillsborough StRaleigh, NC 27606Phone; (919) 515-4480E-mail: barbara_sherry@We study reovirus-induced myocarditis (cardiac inflammation and tissue damage) in mice as a model for this important human disease. Recently, we have focused on the cardiac response to viral infection, with particular emphasis on viral induction of the anti-viral cytokine interferon-beta in cardiac cells. We are interested in both the viral genes that stimulate this response, and the cardiac transcription factors and anti-viral proteins that are central to protection against disease. Our approaches, using primarily molecular techniques, include the use of transgenic mice and primary cardiac myocyte cell cultures.Sikes, Michael, PhDDepartment of MicrobiologyNCSU Gardner Hall, Campus Box 7615Raleigh, NC 27695Phone: (919) 513-0528E-mail: mike_sikes@As different cells in the body develop, they selectively use specific genes while ignoring others. In fact, development of multicellular organisms is absolutely dependent on differential gene regulation. But how genes are programmed to be activated or silenced at the right time remains a mystery. The research in our laboratory investigates the epigenetic changes that govern selective gene usage during lymphocyte development. Unlike other tissues, lymphocytes develop in discreet stages that can be easily followed using cell surface marker proteins, and for which individual cell line models exist. Specifically, we study the epigenetic programs that regulate the developmentally-timed activation and inactivation of the genes that encode the antibody and T cell receptor molecules. These genes are unique in the body in that they undergo a process of genetic recombination. We believe that transcriptional promoters positioned throughout each gene serve as nucleation points for transcription factors and histone modifiers that work together to shape local windows of accessible chromatin in response to developmental cues. Work is underway to test this hypothesis and to define the protein factors involved.Suter, Steven, VMD, MS, PhDDepartment of Clinical SciencesNCSU College of V eterinary Medicine, Campus Box 84014700 Hillsborough StRaleigh, NC 27606Phone: (919) 513-0813E-mail: steven_suter@My research interests focus primarily on hematologic malignancies in companion animals, specifically canine and feline lymphoma. Elucidating the underlying molecular abnormalities associated with these diseases, as well as the development of novel therapeutics is the main thrust of my research. Although canine lymphoma is phenotypically and biologically similar to human non-Hodgkin’s diffuse large B-cell lymphoma, it is not known if these diseases share similar genetic perturbations. We aim to begin to elucidate these perturbations in dogs with lymphoma to both enhance dog lymphoma as a pertinent large animal model of human non-Hodgkin’s lymphoma and develop more targeted therapeutics for this disease.Tompkins, Mary, DVM, PhDDepartment of Population Health and PathobiologyNCSU College of V eterinary Medicine, Campus Box 84014700 Hillsborough StRaleigh, NC 27606(919) 513-6255E-mail: mary_tompkins@The research in my laboratory is directed towards understanding the immunopathogenesis of feline retrovirus infection. In particular, we are examining mechanisms of virus-induced immunosuppression and persistence, especially alterations in cytokine regulation and cell-mediated immunity. We have been studying the immunopathogenesis of feline immunodefic iency virus (FIV), which is one of the best animal models for HIV infection. Our early studies described alterations in peripheral blood lymphocyte subset numbers, in vivo virus tropism, and disease progression. More recently we have described in detail cytokine dysregulation associated with FIV infection that leads to the inability of the infected cat to mount a successful cell mediated immune response to a secondary intracellular pathogen.Tompkins, Wayne, PhDDepartment of Population Health and PathobiologyNCSU College of V eterinary Medicine, Campus Box 84014700 Hillsborough StRaleigh, NC 27606Phone: (919) 515-7394E-mail: wayne_tompkins@The focus of my research is immunopathogenesis of FIV infection in the cat: a model for human HIV infection. We are studying the cellular and molecular basis of T cell dysfunction and progression to AIDS in FIV-infected cats, utilizing RT-qcPCR and multi-color flow cytometry to define the receptor phenotype and cytokine profiles of CD4-positive and CD8-positive T cells. We are specifically exploring the role of B7 co-stimulatory molecules and the cytokines IL-10 and TGF-beta in mediating T cell anergy and apoptosis.Tonkonogy, Susan, PhDDepartment of Population Health and PathobiologyNCSU College of V eterinary Medicine, Campus Box 84014700 Hillsborough StRaleigh, NC 27606Phone: (919) 513-6252E-mail: sue_tonkonogy@The overall goal of my research is to identify the molecular mechanisms that regulate the intestinal immune response. Our current approach is to determine the patterns of cytokines produced by T cells, B cells, macrophages, and dendritic cells isolated from mucosal lymphoid tissue of genetically manipulated rodents that spontaneously develop chronic intestinal inflammation when maintained in specific pathogen free housing. Germ-free rodents with identical genetic alterations do not develop inflammation, implicating the microorganisms that colonize the intestinal tract in the initiation of disease. The long-range goal of these studies is to provide a basis for designing therapeutic strategies aimed towards down-regulating the intestinal immune response that we postulate to be an underlying cause of the chronic inflammation that occurs in inflammatory bowel diseases.Ward, Marsha, PhDImmunotoxicology BranchU.S. Environmental Protection AgencyResearch Triangle Park, NC 27711Phone: (919) 541-1193E-mail: ward.marsha@My research interests involve the assessment of indoor environmental contaminants, particularly fungi for the potential to cause allergy/asthma using laboratory rodent models. The focus of our studies is hazard identification including 1) the identification and characterization of the allergenic proteins and 2) the identification of potential biomarkers that differentiate an allergic response from a non-allergic inflammatory response. Additionally, we are interested in the area of food allergies that could occur due to the introduction of genetically modified crops.Y oder, Jeffrey, PhDDepartment of Molecular Biomedical SciencesNCSU College of V eterinary Medicine, Campus Box 84014700 Hillsborough StRaleigh, NC 27606Phone: (919)-515-7406E-mail: jeff_yoder@Web site: /~jayoder/。

汽车发动机英文参考文献(精选120个最新))

汽车发动机是为汽车提供动力的装置，是汽车的心脏，决定着汽车的动力性、经济性、稳定性和环保性。

下面是搜索整理的汽车发动机英文参考文献，欢迎借鉴参考。

汽车发动机英文参考文献一：[1]Barouch Giechaskiel,Ricardo Suarez-Bertoa,Tero L?hde,Michael Clairotte,Massimo Carriero,Pierre Bonnel,Maurizio Maggiore. Evaluation of NO x emissions of a retrofitted Euro 5 passenger car for the Horizon prize “Engine retrofit”[J]. Environmental Research,2018,166.[2]Shixuan Wang,Ying Liu,Carla Di Cairano-Gilfedder,Scott Titmus,Mohamed M. Naim,Aris A. Syntetos. Reliability Analysis for Automobile Engines: Conditional Inference Trees[J]. Procedia CIRP,2018,72.[3]Kévin Rosset,Violette Mounier,Eliott Guenat,Jürg Schiffmann. Multi-objective optimization of turbo-ORC systems for waste heat recovery on passenger car engines[J]. Energy,2018,159.[4]Mohamed Kamal Ahmed Ali,Hou Xianjun,Mohamed A.A. Abdelkareem,M. Gulzar,A.H. Elsheikh. Novel approach of the graphene nanolubricant for energy saving via anti-friction/wear in automobile engines[J]. Tribology International,2018,124.[5]Shweta Tripathi,K.A. Subramanian. Control of fuel spray wall impingement on piston bowl in palm acid oil biodiesel fueled direct injection automotive engine using retarded injection timing, EGR and increased compression ratio[J]. Applied Thermal Engineering,2018,142.[6]Gianfranco Gagliardi,Francesco Tedesco,Alessandro Casavola. A LPV modeling of turbocharged spark-ignition automotive engine oriented to fault detection and isolation purposes[J]. Journal of the Franklin Institute,2018.[7]Gritsada Sua-Iam,Natt Makul. Innovative utilization of foundry sand waste obtained from the manufacture of automobile engine parts as a cement replacement material in concrete production[J]. Journal of Cleaner Production,2018.[8]Kanhu Charan Nayak,Prashant P. Date. Manufacturing of light automobile engine piston head using sheet metal[J]. Procedia Manufacturing,2018,15.[9]Yisong Chen,Jinqiu Ma,Bin Han,Peng Zhang,Haining Hua,Hao Chen,Xin Su. Emissions of automobiles fueled with alternative fuels based on engine technology: A review[J]. Journal of Traffic and Transportation Engineering (English Edition),2018.[10]Xinfeng Zhang,Minghui Luo,Wei Dai,Chuanqi Yao,Jiwen Wang,DaojinHuang,Chunyang Wang. Automotive fuel cell engine test cell design and its thermal flow analysis[J]. International Journal of Hydrogen Energy,2018.[11]K. Sato,T. Sadahiro,M. Yamazaki,M. Iwase. Throttle Valve Control of Automotive Engine based on Boundary Model[J]. IFAC PapersOnLine,2018,51(13).[12]Ajay Kumar Maddineni,Dipayan Das,Ravi Mohan Damodaran. Numerical Investigation of Pressure and Flow characteristics of Pleated Air Filter System for Automotive Engine Intake Application[J]. Separation and Purification Technology,2018.[13]Masahiro Yamazaki,Kotoru Sato,Katsuya Shinozaki,Masami Iwase. Boundary Modeling and Identification of Normal Operation for Automobile Engine[J]. IFAC PapersOnLine,2018,51(31).[14]Guo Bin,Chen Hong,Song Dafeng. Research on Fast Matching Method of Power System Parameters of Parallel Hybrid Electric Vehicles[J]. IFAC PapersOnLine,2018,51(31).[15]Natália de Assis Brasil Weber,Bárbara Pacheco da Rocha,Paulo Smith Schneider,Luiz Carlos Daemme,Renato de Arruda Penteado Neto. Energy and emission impacts of liquid fueled engines compared to electric motors for small size motorcycles based on the Brazilian scenario[J]. Energy,2019,168.[16]Francesco Del Pero,Massimo Delogu,Marco Pierini. Life Cycle Assessment in the automotive sector: a comparative case study of Internal Combustion Engine (ICE) and electric car[J]. Procedia Structural Integrity,2018,12.[17]Shan Lin,Li Zhao,Shuai Deng,Jiaxin Ni,Ying Zhang,Minglu Ma. Dynamic performance investigation for two types of ORC system driven by waste heat of automotive internal combustion engine[J]. Energy,2019,169.[18]Zhang Jian,Piao Zhong-yu,Liu Shi-ying,Su Sheng-wei,Deng Li-jun. Investigation of wear behavior of graphite coating on aluminum piston skirt of automobile engine[J]. Engineering Failure Analysis,2019.[19]Karsten Wittek,Frank Geiger,Jakob Andert,Mario Martins,Vitor Cogo,Thompson Lanzanova. Experimental investigation of a variable compression ratio system applied to a gasoline passenger car engine[J]. Energy Conversion and Management,2019,183.[20]Adnan Kadhim Rashid,Mohd Radzi Abu Mansor,Alexandru Racovitza,Radu Chiriac. Combustion Characteristics of Various Octane Rating Fuels for Automotive Thermal Engines Efficiency Requirements[J]. Energy Procedia,2019,157.[21]Marlon Cadrazco,Alexander Santamaría,John R. Agudelo. Chemical and nanostructural characteristics of the particulate matter produced by renewable diesel fuel in an automotive diesel engine[J]. Combustion and Flame,2019,203.[22]Kenneth Holmberg,Ali Erdemir. The impact of tribology on energy use and CO 2 emission globally and in combustion engine and electric cars[J]. Tribology International,2019,135.[23]Hongli Gao,Fujun Zhang,Sufei Wang,Hao Wu,Zhengkai Wang. Effect of Characteristic Parameters on the Magnetic Properties of Voice Coil Motor for Direct Fuel Injection in Gasoline Engine[J]. Energy Procedia,2019,158.[24]Xunan Gao,Bojan Savic,Roland Baar. A numerical procedure to model heat transfer in radial turbines for automotive engines[J]. Applied Thermal Engineering,2019,153.[25]Senthil Kumar Kandasamy,Arun Saco Selvaraj,Thundil Karuppa Raj Rajagopal. Experimental investigations of ethanol blended biodiesel fuel on automotive diesel engine performance, emission and durability characteristics[J]. Renewable Energy,2019,141.[26]Ganesh Duraisamy,Murugan Rangasamy,Nagarajan Govindan. A comparative study on methanol/diesel and methanol/PODE dual fuel RCCI combustion in an automotive diesel engine[J]. Renewable Energy,2020,145.[27]Nosratollah Izadiamoli,Hoseyn Sayyaadi. Conceptual design, optimization, and assessment of a hybrid Otto-Stirling engine/cooler for recovering the thermal energy of the exhaust gasses for automotive applications[J]. Energy Conversion and Management,2018,171.[28]Federico Millo,Pranav Arya,Fabio Mallamo. Optimization of automotive diesel engine calibration using genetic algorithm techniques[J]. Energy,2018,158.[29]Yonggyu Lee,Seungmook Oh,Changup Kim,Junsun Lee,Kanghun Lee,Junghwan Kim. The dual-port fuel injection system for fuel economy improvement in an automotive spark-ignition gasoline engine[J]. Applied Thermal Engineering,2018,138.[30]S. d'Ambrosio,A. Ferrari,D. Iemmolo,A. Mittica. Dependence of combustion noise on engine calibration parameters by means of the response surface methodology in passenger car diesel engines[J]. Applied Thermal Engineering,2019.汽车发动机英文参考文献二：[31]Ivan Bortel,Ji?í Vávra,Michal Takáts. Effect of HVO fuel mixtures onemissions and performance of a passenger car size diesel engine[J]. Renewable Energy,2019,140.[32]Jaeho Cho,Kangjin Kim,Sungha Baek,Cha-Lee Myung,Simsoo Park. Abatement potential analysis on CO 2 and size-resolved particle emissions from a downsized LPG direct injection engine for passenger car[J]. Atmospheric Pollution Research,2019.[33]Jamie Sleigh,Catherine E. Warnaby. Finding the starter motor for the engine of consciousness[J]. British Journal of Anaesthesia,2019,123(3).[34]S. Prakash,M. Prabhahar,S. Sendilvelan,R. Venkatesh,Sanjay Singh,K. Bhaskar. Experimental studies on the performance and emission characteristics of an automobile engine fueled with fish oil methyl ester to reduce environmental pollution[J]. Energy Procedia,2019,160.[35]Sabino Caputo,Federico Millo,Giulio Boccardo,Andrea Piano,Giancarlo Cifali,Francesco Concetto Pesce. Numerical and experimental investigation of a piston thermal barrier coating for an automotive diesel engine application[J]. Applied Thermal Engineering,2019,162.[36]Nicole D?rr,Adam Agocs,Charlotte Besser,Andjelka Risti?,Marcella Frauscher. Engine Oils in the Field: A Comprehensive Chemical Assessment of Engine Oil Degradation in a Passenger Car[J]. Tribology Letters,2019,67(3).[37]Sumanchandran Devendran,Rajeshkumar Ramasamy,Varatharaj Neelakandan,Thulasirajan Ganesan,Praveen Chakrapani Rao. Failure assessment using accelerated testing on IC engine’s starter motor for reliability improvement[J]. Life Cycle Reliability and Safety Engineering,2019,8(2).[38]Jaegu Choi,Jongmin Lee,Namgyu Jun,Chang-Sung Seok,Sunghwan Park,Gayeon Kim. Development of Laboratory Fatigue Testing Apparatus for Automotive Vehicle Engine Valve Simulating Actual Operating Conditions[J]. International Journal of Precision Engineering and Manufacturing,2019,20(7).[39]Pavel Nicolaie,Chiriac Radu,Birtas Adrian,Draghici Florin,Dinca Mihai. On the improvement by laser ignition of the performances of a passenger car gasoline engine.[J]. Optics express,2019,27(8).[40]Ahmadipour Fatemeh,Esmaeili Sari Abbas,Bahramifar Nader. Characterization, concentration and risk assessment of airborne particles using car engine air filter (case study: Tehran metropolis).[J]. Environmental geochemistry and health,2019.[41]Sleigh Jamie,Warnaby Catherine E. Finding the starter motor for the engine of consciousness.[J]. British journal of anaesthesia,2019,123(3).[42]Derry Matthew J,Smith Timothy,O'Hora Paul S,Armes Steven P. Block Copolymer Nanoparticles Prepared via Polymerization-Induced Self-Assembly Provide Excellent Boundary Lubrication Performance for Next-Generation Ultralow-Viscosity Automotive Engine Oils.[J]. ACS applied materials & interfaces,2019.[43]. Hyundai Motor Company; Patent Issued for Continuous Variable Valve Duration Apparatus And Engine Provided With The Same (USPTO 10,060,307)[J]. Journal of Engineering,2018.[44]. Mazda Motor Corporation; Patent Issued for Engine Control Device (USPTO 10,060,372)[J]. Journal of Engineering,2018.[45]. Automotive Engine Market 2018 Global Industry Outlook By Size, Key Players, Trends, Share, Suppliers, Statistics, Sales, Growth, And Regional Forecast To 2023[J]. M2 Presswire,2018.[46]. Mathematics - Applied Mathematics; Researchers at University of Calabria Report New Data on Applied Mathematics (A LPV modeling of turbocharged spark-ignition automotive engine oriented to fault detection and isolation purposes)[J]. Journal of Transportation,2018.[47]. Ford Global Technologies LLC; "Hybrid Module, Hybrid Unit And Motor Vehicle As Well As Starting Process For An Internal Combustion Engine" in Patent Application Approval Process (USPTO 20180238291)[J]. Politics & Government Week,2018.[48]. Mazda Motor Corporation; Patent Application Titled "Engine Control Device" Published Online (USPTO 20180245529)[J]. Energy Weekly News,2018.[49]. Hitachi Automotive Systems Ltd.; "Cooling Device For Internal Combustion Engine Of Vehicle And Control Method Thereof" in Patent Application Approval Process (USPTO 20180245504)[J]. Journal of Transportation,2018.[50]. Automotive Engine Valves Market 2018 Global Industry Size, Key Player, Share, Mergers, Acquisition, Growth Analysis By Valves Type, Technology, Fuel Type, Vehicle And Region To 2023[J]. M2 Presswire,2018.[51]. Litens Automotive Partnership; Patent Issued for Isolator For Use With Engine That Is Assisted Or Started By An MGU Or A Motor Through An Endless Drive Member (USPTO 10,060,502)[J]. Journal of Engineering,2018.[52]. Honda Motor Co. Ltd.; Patent Issued for Supercharged Engine (USPTO 10,060,337)[J]. Journal of Engineering,2018.[53]. Hyundai Motor Company; Patent Issued for Method Of And System For Generating Virtual Engine Sound (USPTO 10,059,260)[J]. Journal of Engineering,2018.[54]. Suzuki Motor Corporation; Researchers Submit Patent Application, "Lubrication Structure For Internal Combustion Engine", for Approval (USPTO 20180238203)[J]. Politics & Government Week,2018.[55]. Energy; Studies from Brunel University in the Area of Energy Described (Expander Technologies for Automotive Engine Organic Rankine Cycle Applications)[J]. Journal of Engineering,2018.[56]. Hitachi Automotive Systems Ltd.; Patent Application Titled "Cooling Device For Internal Combustion Engine Of Vehicle And Control Method Thereof" Published Online (USPTO 20180245503)[J]. Journal of Transportation,2018.[57]. Honda Motor Co.Ltd.; Patent Application Titled "Internal Combustion Engine For Vehicle" Published Online (USPTO 20180245509)[J]. Politics & Government Week,2018.[58]. Honda Motor Co. Ltd.; Patent Issued for V Engine Having Valve Property Varying Mechanism (USPTO 10,066,553)[J]. Journal of Engineering,2018.[59]. Nissan Motor Co. Ltd.; Patent Issued for Vehicle Engine Stop Control Device (USPTO 10,065,646)[J]. Journal of Transportation,2018.[60]. Yamaha Motor Power Products Kabushiki Kaisha; Patent Issued for Engine (USPTO 10,066,522)[J]. Journal of Engineering,2018.汽车发动机英文参考文献三：[61]. Continental Automotive Systems Inc.; Patent Application Titled "Connected Energy Management And Autonomous Driving Strategy For Engine Cylinder Deactivation" Published Online (USPTO 20180238249)[J]. Journal of Transportation,2018.[62]. Honda Motor Co. Ltd.; Patent Issued for Variable Valve Mechanism For Internal Combustion Engine (USPTO 10,066,518)[J]. Journal of Engineering,2018.[63]. Suzuki Motor Corporation; Patent Issued for Engine For Outboard Motor (USPTO 10,059,416)[J]. Journal of Engineering,2018.[64]. MAHLE International GmbH; "Internal Combustion Engine For A Motor Vehicle" in Patent Application Approval Process (USPTO 20180216583)[J]. Energy Weekly News,2018.[65]. Hyundai Motor Company; "Engine Cooling System" in Patent Application Approval Process (USPTO 20180163608)[J]. Energy Weekly News,2018.[66]Jedd Cole. Grinder Simplifies Automotive Engine Part Production[J]. Modern Machine Shop,2018,91(3).[67]. Energy; Reports Outline Energy Study Results from Swiss Federal Institute of Technology in Lausanne (Multi-objective optimization of turbo-ORC systems for waste heat recovery on passenger car engines)[J]. Energy Weekly News,2018.[68]. Science - Applied Sciences; Researchers from Inha University Provide Details of New Studies and Findings in the Area of Applied Sciences (A New Method for Active Cancellation of Engine Order Noise in a Passenger Car)[J]. Science Letter,2018.[69]. Honda Motor Co. Ltd.; Researchers Submit Patent Application, "Engine Generator", for Approval (USPTO 20180283340)[J]. Energy Weekly News,2018.[70]. Mazda Motor Corporation; Patent Application Titled "Control Device Of Compression Self-Ignition Engine" Published Online (USPTO 20180283296)[J]. Energy Weekly News,2018.[71]. Continental Automotive GmbH; "High-Pressure Fuel Pump And Fuel Supply Device For An Internal Combustion Engine, In Particular Of A Motor Vehicle" in Patent Application Approval Process (USPTO 20180283336)[J]. Energy Weekly News,2018.[72]. Kia Motors Corporation; "Hybrid Vehicle And Method Of Controlling Engine Start" in Patent Application Approval Process (USPTO 20180297578)[J]. Energy Weekly News,2018.[73]. Mazda Motor Corporation; Patent Issued for Fuel Injection Control Device For Direct-Injection Engine (USPTO 10,119,492)[J]. Energy Weekly News,2018.[74]. Nissan Motor Co. Ltd.; Patent Issued for Engine Control Device And Engine Control Method (USPTO 10,119,486)[J]. Energy Weekly News,2018.[75]. Johnson Electric S.A.; "Motor, Circuit Board, And Engine Cooling Module Including The Motor" in Patent Application Approval Process (USPTO 20180337578)[J]. Electronics Business Journal,2018.[76]. Mazda Motor Corporation; Patent Application Titled "Structure Of Mounting Intake Air Temperature Sensor Of Engine With Supercharger" Published Online (USPTO 20180340496)[J]. Energy Weekly News,2018.[77]. Kia Motors Corporation; "System And Method For Controlling Engine Clutch" in Patent Application Approval Process (USPTO 20180335096)[J]. Energy Weekly News,2018.[78]. Kia Motors Corporation; "Method For Starting Engine For Hybrid Electric Vehicle" in Patent Application Approval Process (USPTO 20180340503)[J]. Energy Weekly News,2018.[79]. Kia Motors Corporation; "Piston For Engine" in Patent Application Approval Process (USPTO 20180340491)[J]. Energy Weekly News,2018.[80]Maniatis P,Wagner U,Koch T. A model-based and experimental approach for the determination of suitable variable valve timings for cold start in partial load operation of a passenger car single-cylinder diesel engine[J]. International Journal of Engine Research,2019,20(1).[81]Tauzia Xavier,Maiboom Alain,Karaky Hassan,Chesse Pascal. Experimental analysis of the influence of coolant and oil temperature on combustion and emissions in an automotive diesel engine[J]. International Journal of Engine Research,2019,20(2).[82]. Kia Motors Corporation; Patent Issued for Engine Idle Operation Control Method And System For Heating Of Hybrid Electric Vehicle (USPTO 10,220,828)[J]. Energy Weekly News,2019.[83]. Suzuki Motor Corporation; Patent Issued for Engine Control Device And Engine Control Method (USPTO 10,232,924)[J]. Computers, Networks & Communications,2019.[84]. Kia Motors Corporation; "Gasoline Direct Injection Engine" in Patent Application Approval Process (USPTO 20190078500)[J]. Energy Weekly News,2019.[85]. Proposed Information Collection Request; Comment Request; Motor Vehicle and Engine Compliance Program Fees (Renewal), EPA ICR 2080.07, OMB Control No. 2060-0545[J]. The Federal Register / FIND,2019,84(070).[86]. Energy; Findings from Federal University of Santa Maria in the Area of Energy Reported (Experimental Investigation of a Variable Compression Ratio System Applied To a Gasoline Passenger Car Engine)[J]. Energy Weekly News,2019.[87]. Energy; Studies from Federal University in the Area of Energy Described (Energy and Emission Impacts of Liquid Fueled Engines Compared To Electric Motors for Small Size Motorcycles Based On the Brazilian Scenario)[J]. Energy Weekly News,2019.[88]. Central Motor Wheel Co. Ltd.; Patent Application Titled "Thermoacoustic Engine, And Designing Method For Thermoacoustic Engine" Published Online (USPTO 20190085833)[J]. Energy Weekly News,2019.[89]. Kia Motors Corporation; Researchers Submit Patent Application, "Apparatus For Improving Efficiency Of Turbocharger Engine", for Approval (USPTO 20190093548)[J]. Energy Weekly News,2019.[90]. Engineering - Automobile Engineering; University of Birmingham Reports Findings in Automobile Engineering (On-board Thermochemical Energy Recovery Technology for Low Carbon Clean Gasoline Direct Injection Engine Powered Vehicles)[J]. Energy Weekly News,2019.汽车发动机英文参考文献四：[91]. Kia Motors Corporation; "Method And Device For Controlling Engine During Idle Purge Of Canister" in Patent Application Approval Process (USPTO 20190112993)[J]. Energy Weekly News,2019.[92]. Hitachi Automotive Systems Ltd.; Patent Issued for Fuel Injection System For Internal Combustion Engine (USPTO 10,267,253)[J]. Energy Weekly News,2019.[93]Song Kang,Upadhyay Devesh,Xie Hui. A physics-based turbocharger model for automotive diesel engine control applications[J]. Proceedings of the Institution of Mechanical Engineers,2019,233(7).[94]. Hitachi Automotive Systems Ltd.; Patent Issued for Engine Control Device (USPTO 10,309,366)[J]. Energy Weekly News,2019.[95]. Continental Automotive GmbH; "Gas Internal Combustion Engine With Auxiliary Starting System" in Patent Application Approval Process (USPTO 20190162123)[J]. Energy Weekly News,2019.[96]. Fuel Research; Studies from Volvo Car Group Add New Findings in the Area of Fuel Research (Impact of Closely-coupled Triple-pilot and Conventional Double-pilot Injection Strategies In a Ld Diesel Engine)[J]. Energy Weekly News,2019.[97]. Kia Motors Corporation; Patent Issued for Engine Start Control Method (USPTO 10,316,814)[J]. Biotech Business Week,2019.[98]. Kia Motors Corporation; "Apparatus And Method For Starting Engine Of Mild Hybrid Electric Vehicle" in Patent Application Approval Process (USPTO 20190184972)[J]. Energy Weekly News,2019.[99]. Energy; Findings from K.N. Toosi University of Technology Provides New Data on Energy (Conceptual design, optimization, and assessment of a hybrid Otto-Stirling engine/cooler for recovering the thermal energy of the exhaust gasses for automotive ...)[J]. Energy Weekly News,2019.[100]. Toyota Jidosha Kabushiki Kaisha; "Automotive Engine Coolant Composition, Automotive Engine Concentrated Coolant Composition, And Method Of Operating Internal Combustion Engine" in Patent Application Approval Process (USPTO 20190194516)[J]. Energy Weekly News,2019.[101]. Kia Motors Corporation; "Engine Control Method For Heating Of Hybrid Electric Vehicle" in Patent Application Approval Process (USPTO 20190193516)[J]. Energy Weekly News,2019.[102]. Kia Motors Corporation; "Vehicle And Method For Controlling Engine Startup Reference Power" in Patent Application Approval Process (USPTO 20190202432)[J]. Energy Weekly News,2019.[103]. Energy; Technical University Details Findings in Energy (A fully automated smooth calibration generation methodology for optimization of latest generation of automotive diesel engines)[J]. Energy Weekly News,2019.[104]. Black &Decker Inc.; "Battery And Motor System For Replacing Internal Combustion Engine" in Patent Application Approval Process (USPTO 20190238083)[J]. Energy Weekly News,2019.[105]. Mazda Motor Corporation; "Exhaust Gas Control Device, Method, And Computer Program Product For An Engine" in Patent Application Approval Process (USPTO 20190234330)[J]. Energy Weekly News,2019.[106]Dongha Kim,JongRoul Woo,Jungwoo Shin,Jongsu Lee,Yongdai Kim. Can search engine data improve accuracy of demand forecasting for new products? Evidence from automotive market[J]. Industrial Management & Data Systems,2019,119(5).[107]R. Ellappan,S. Arumugam. The effect of corrosion inhibitor on corrosion of automotive materials in Biodegradable engine oil[J]. IOP Conference Series: Materials Science and Engineering,2018,390(1).[108]P. Wi?niowski,M ?l?zak,A Niewczas,T Szczepański. Method for synthesizing the laboratory exhaust emission test from car engines based on road tests[J]. IOP Conference Series: Materials Science and Engineering,2018,421(4).[109]J Kaszkowiak,M Markiewicz-Patalon. The impact on the manner of loading theengines powered with biogas and natural gas on the selected parameters of the motor oil[J]. IOP Conference Series: Materials Science and Engineering,2018,421(4).[110]A Wolff. Numerical analysis of gas flow through the labyrinth seal of piston rings of an automotive IC engine[J]. IOP Conference Series: Materials Science and Engineering,2018,421(4).[111]Z Kneba. Research on the phenomena of warming up and free cooling down the car engine[J]. IOP Conference Series: Materials Science and Engineering,2018,421(4).[112]N C Nutu,C Pana,N Negurescu,A Cernat,D Fuiorescu,L Nemoianu. An experimental approach on fuelling a passenger car diesel engine with LPG[J]. IOP Conference Series: Materials Science and Engineering,2018,444(7).[113]T Ulian,V Vornicu,E Rakosi,G Manolache,S Talif,I Agape. The study of the performance improvement possibilities by using the principle of zonal cooling for the automotive engine[J]. IOP Conference Series: Materials Science and Engineering,2018,444(7).[114]V Serevina,A A Azhar,T Sutandi,K Sumeru. Effect Of Engine Speed On The Performance Of Automotive Air Conditioning System Using R134a And R152a As Refrigerants[J]. Journal of Physics: Conference Series,2019,1150(1).[115]Willyanto Anggono,Sutrisno,Fandi D Suprianto,Muji Setiyo,Rendy Wibisono,Gabriel Jeremy Gotama. Experimental investigation of the effect of Nephelium Lappaceum seed biodiesel to the automotive diesel engine performance[J]. IOP Conference Series: Earth and Environmental Science,2019,257(1).[116]Guorui Jia,Huanhuan Ren,Dongchang Zhao,Chuan Chen,Rujie Yu,Peng Ge,Shaohui Liu. Numerical Simulation of Multiple Injections on the Combustion of Reactivity Distribution in Automotive Engine[J]. IOP Conference Series: Earth and Environmental Science,2019,252(3).[117]Xitong Zhang,Tao Peng,Fuxin Mao,Ming Cheng. Research on Key Technologies of Integrated Teaching Platform for Automotive Engine ECU Control System[J]. Journal of Physics: Conference Series,2019,1237(4).[118]Huanhuan Ren,Guorui Jia,Dongchang Zhao,Chuan Chen,Rujiex Yu,Peng Ge,Shaohui Liu. Simulation Study of Injection Strategy on the Emission in Automotive Engine[J]. IOP Conference Series: Earth and Environmental Science,2019,252(3).[119]Olufemi Sylvester Bamisaye,Anthony Yinka Oyerinde,Ubong Akpan Essien. Investigation of the Effects of Air-Conditioning System on the Temperature and Speed of Automobile Engine Using Paired T-Test and Regression Analysis[J]. Open AccessLibrary Journal,2019,06(01).[120]Huali Guo,Jia Cui,Guofu Wang,Hongwang Zhao. Analysis and Research on the Teaching Principle of Automotive Engine Based on CDIO Concept[P]. Proceedings of the 2018 International Conference on Sports, Arts, Education and Management Engineering (SAEME 2018),2018.以上就是关于汽车发动机英文参考文献的分享，希望对你有所帮助。

如何体会戏剧之美英语作文

Drama,as an art form,has the power to captivate audiences and transport them into the world of the story.To fully appreciate the beauty of drama,one must engage with it on multiple levels.Here are some ways to experience and understand the beauty of drama:1.Understanding the Script:The foundation of any drama is its script.Reading the script allows you to delve into the characters dialogues,monologues,and the underlying themes. It helps you to understand the motivations and emotions of the characters.2.Appreciating the Performance:The actors portrayal of the characters is crucial to the dramas impact.Observe how they use body language,facial expressions,and voice modulation to bring the script to life.The subtleties of their performance can reveal deeper layers of the characters.3.Analyzing the Direction:The directors vision shapes the overall experience of the drama.Pay attention to the staging,the use of space,and how the director guides the actors to interpret the script.The directors choices can enhance the narrative and emotional depth of the drama.4.Noticing the Set and Costume Design:The visual elements of a drama,such as the set and costumes,contribute to the atmosphere and period of the play.They can provide context and help to immerse the audience in the world of the drama.5.Listening to the Sound and Music:Sound effects and music can underscore the mood and enhance the emotional impact of a scene.They can also serve as a narrative device, signaling changes in time or place.6.Engaging with the Story:Allow yourself to be drawn into the story.Empathize with the characters,feel the tension,and experience the highs and lows of the narrative.The more you invest emotionally,the more you will appreciate the drama.7.Reflecting on the Themes and Messages:Dramas often explore universal themes and convey messages about society,human nature,and morality.Reflect on what the play is trying to say and how it relates to your own experiences and beliefs.8.Discussing with Others:Sharing your thoughts and interpretations with others can provide new insights and deepen your appreciation of the drama.Engage in discussions, whether in a formal setting like a literature class or informally with friends.9.Experiencing Different Genres:Drama encompasses a wide range of genres,from tragedies and comedies to historical plays and modern dramas.Experiencing differenttypes of drama can help you appreciate the diversity and richness of the art form.10.Attending Live Performances:There is a unique energy and immediacy to live performances that cannot be replicated by film or television.The interaction between the performers and the audience can be a powerful part of the experience.By engaging with drama in these ways,you can develop a deeper understanding and appreciation for this art form,allowing you to see the beauty in the stories,characters, and performances that make up the world of drama.。

Title of the article(英文文题)：

Title of the article（英文文题）:[在上方放置英文文章标题。

本刊是国际性开放存取学术期刊，为了满足全球各大数据库收录条件，本刊刊登的所有中文论文都应该有相应的英文文题和摘要，以利于中文学术成果的推广。

][英文文题下放英文作者名字和单位].ZHANG Yi-yi1,WANG San-yi21Peking University Health Science Center, Peking,China2Shanghai zhongshan hospital，Shanghai,ChinaAbstract（英文摘要）:[摘要（Abstract）是对整篇文章做出的简要介绍，一般在300~500个单词之间，摘要应尽量避免特殊的缩写和简写。

] Key Words（英文关键词）：[一般需要3~6个英文关键词，避免缩写和简写]中文文题:[上方放置中文文章标题][中文文题下放中文作者名字和单位].张一一1，王三一21北京大学医学院，北京，中国2上海中山医院，上海，中国中文摘要:[摘要是对整篇文章做出的简要介绍，一般在200~400个字之间，摘要应尽量避免特殊的缩写和简写。

]关键词:[一般需要3~6个中文关键词，避免缩写和简写]前言[把相应文字粘贴在此处]1×××××（1级标题）1.1 ×××××××××××（2级标题）××××××××××××××××××××××××，××××××××××××××××××××××，××××××××××××××××××[1]。

英语本科毕业论文-《飘》中瑞德·巴特勒的人物性格特点分析

河北师范大学高等教育自学考试本科毕业论文题目：《飘》中瑞德·巴特勒的人物性格特点分析On the Characterization of Rhett Butler in Gone With the Wind摘要:《飘》是世界文学经典名著之一，是由美国文学作家玛格丽特·米切尔所著。

瑞德·巴特勒是小说中的男主人公。

他英俊潇洒，花钱任意，衣着时髦。

他很高兴以最糟糕的形式出现在公众面前。

一个取乐与轻蔑的微笑，一个无可辩驳的评论，一个优雅的鞠躬，无不显露出他的玩世不恭与睿智。

他说他绝不为抛弃他的南方制度而战，但他在战争的最后时刻加入军队。

他出身于贵族，但他是贵族的叛逆者。

他被叫做无赖，卖国贼，但他为南方和人民做过许多好事。

在生意上，他事业有成。

在爱情上，他一败涂地。

他怀着一个男人对一个女人的爱所能达到的最高程度在爱思佳丽特，但因为了解她而不敢直言相告,导致一场爱情悲剧。

关键词：英俊; 玩世不恭; 睿智; 精明Abstract:Gone with the wind, which was written by Margaret Mitchell, is one of the most popular masterpieces in the world. Rhett Butler is the leading man-role in this novel. He is handsome, and he spent money freely. He wears clothes which are always the height of style and tailoring. He is happy to present himself in the worst possible light with an amused, contempt smile, an unanswerable remarks and a graceful bow. These show his cynicism and sagaciousness. He says he would never uphold the South that cast him, but he joins the army at the eleventh-hour of the war. He was born as a gentleman but a renegade. He is called a rascal and a traitor, but he does a lot of good deeds for the South and the people. He succeeds in business but fails in love. He loves Scarlett as much as a man can love a woman, but he can’t tell her because he knows her. It is a tragic love.Key words: handsome;cynical; sagacious; shrewdContentAbstract (3)Abstract in Chinese (4)I. Introduction (5)1. Brief introduction of the A uthor (6)2. Brief introduction of the novel’s content (7)3. The social background of Gone with the winda. The Civil War in the U.S.A (8)b. The Reconstruction after the Civil War (10)II. Analysis of the character of Rhett Butler in seven aspects1. He is handsome and charming (11)2. He is a renegade………………………………………………………...14.3. He is cynical and sagacious (16)4. He has a clear understanding of the society and war, and hasthe courage to say the truth (18)5. He is shrewd, farsighted (20)6. He is kind, helpful and he loves the South in his own way.....................22.7. Rhett Butler loves Scarlett O’Hara as much as a man can lovea woman (23)Conclusion (28)Notes (29)Bibliography (30)Introduction1. Brief introduction of the AuthorMargaret Mitchell (November 8, 1900-August 16, 1949) was a famous American writer, who won the Pulitzer Prize in 1937 for her novel Gone with the Wind。

Characterization of Radar Backscatter翻译要点

本科毕业设计(论文)外文资料翻译外文资料题目Characterization of Radar BackscatterResponse of Sand-Covered Surfacesat Millimeter-Wave Frequencies摘要摘要由于干沙的介电常数低和沙表面比较粗糙，沙漠的雷达成像会遭受不足的雷达回波低频微波信号。

然而，操作在毫米波段频率，用以矫正这一缺陷的重要雷达回波产生的表面和体积散射。

由于这样的事实,即砂表面粗糙度大，信号穿透到干砂,这是一个空气和砂颗粒尺寸与波长的一小部分的均匀混合物,产生相当大的体积散射。

本文探讨在干砂表面的面积和体积的散射，以奇特的砂表面的物理性能，发现在沙地沙丘覆盖的地区。

提出了一种非相干模型,描述了角依赖体积散射从干砂在存在一维起涟漪的空气/砂表面。

一组室内实验进行平滑和一维起涟漪的砂表面在ka波段证实,大量散射是毫米波频率,该模型正确地捕捉观察角关系当一维表面波纹出现。

关键词：毫米波（MMW）测量雷达体积散射摘要摘要目录i目录一、引言 (1)二、干砂的物理性质的表征 (5)三、干沙丘表面的造型雷达后向散射响应 (9)四、实验表征 (17)五、结论 (23)附录 (25)参考文献 (29)ii目录一、引言1一、引言世界各地的石油和天然气领域的探索，包括地区的特点是干旱或沙漠地区地震试验中经常使用的。

在这些地区，干沙层往往覆盖底层的基岩，并且其厚度变化从一个区域到下一个区域。

在沙层厚度的基石是低的沙区的地震试验通常是成功的。

如果砂层高于基岩的厚度是先验已知的，那么这些测试的成本可以显著降低。

双频干涉合成孔径雷达（SAR）测量（InSAR）已被提议作为一种映射沙层以上的基岩大面积的沙漠和干旱地区的厚度[1][2]的手段。

双频干涉合成孔径雷达的提议包含两个系统：高频和低频InSAR系统，两者都安装在一个平台上。

高频InSAR 技术被用于确定空气/砂界面的高度，而低频InSAR技术被用于确定的砂/基岩界面的高度。

专八英语阅读

英语专业八级考试TEM-8阅读理解练习册（1）(英语专业2012级)UNIT 1Text AEvery minute of every day, what ecologist生态学家James Carlton calls a global ―conveyor belt‖, redistributes ocean organisms生物.It’s planetwide biological disruption生物的破坏that scientists have barely begun to understand.Dr. Carlton —an oceanographer at Williams College in Williamstown,Mass.—explains that, at any given moment, ―There are several thousand marine species traveling… in the ballast water of ships.‖ These creatures move from coastal waters where they fit into the local web of life to places where some of them could tear that web apart. This is the larger dimension of the infamous无耻的，邪恶的invasion of fish-destroying, pipe-clogging zebra mussels有斑马纹的贻贝.Such voracious贪婪的invaders at least make their presence known. What concerns Carlton and his fellow marine ecologists is the lack of knowledge about the hundreds of alien invaders that quietly enter coastal waters around the world every day. Many of them probably just die out. Some benignly亲切地，仁慈地—or even beneficially — join the local scene. But some will make trouble.In one sense, this is an old story. Organisms have ridden ships for centuries. They have clung to hulls and come along with cargo. What’s new is the scale and speed of the migrations made possible by the massive volume of ship-ballast water压载水— taken in to provide ship stability—continuously moving around the world…Ships load up with ballast water and its inhabitants in coastal waters of one port and dump the ballast in another port that may be thousands of kilometers away. A single load can run to hundreds of gallons. Some larger ships take on as much as 40 million gallons. The creatures that come along tend to be in their larva free-floating stage. When discharged排出in alien waters they can mature into crabs, jellyfish水母, slugs鼻涕虫，蛞蝓, and many other forms.Since the problem involves coastal species, simply banning ballast dumps in coastal waters would, in theory, solve it. Coastal organisms in ballast water that is flushed into midocean would not survive. Such a ban has worked for North American Inland Waterway. But it would be hard to enforce it worldwide. Heating ballast water or straining it should also halt the species spread. But before any such worldwide regulations were imposed, scientists would need a clearer view of what is going on.The continuous shuffling洗牌of marine organisms has changed the biology of the sea on a global scale. It can have devastating effects as in the case of the American comb jellyfish that recently invaded the Black Sea. It has destroyed that sea’s anchovy鳀鱼fishery by eating anchovy eggs. It may soon spread to western and northern European waters.The maritime nations that created the biological ―conveyor belt‖ should support a coordinated international effort to find out what is going on and what should be done about it. (456 words)1.According to Dr. Carlton, ocean organism‟s are_______.A.being moved to new environmentsB.destroying the planetC.succumbing to the zebra musselD.developing alien characteristics2.Oceanographers海洋学家are concerned because_________.A.their knowledge of this phenomenon is limitedB.they believe the oceans are dyingC.they fear an invasion from outer-spaceD.they have identified thousands of alien webs3.According to marine ecologists, transplanted marinespecies____________.A.may upset the ecosystems of coastal watersB.are all compatible with one anotherC.can only survive in their home watersD.sometimes disrupt shipping lanes4.The identified cause of the problem is_______.A.the rapidity with which larvae matureB. a common practice of the shipping industryC. a centuries old speciesD.the world wide movement of ocean currents5.The article suggests that a solution to the problem__________.A.is unlikely to be identifiedB.must precede further researchC.is hypothetically假设地，假想地easyD.will limit global shippingText BNew …Endangered‟ List Targets Many US RiversIt is hard to think of a major natural resource or pollution issue in North America today that does not affect rivers.Farm chemical runoff残渣, industrial waste, urban storm sewers, sewage treatment, mining, logging, grazing放牧,military bases, residential and business development, hydropower水力发电,loss of wetlands. The list goes on.Legislation like the Clean Water Act and Wild and Scenic Rivers Act have provided some protection, but threats continue.The Environmental Protection Agency (EPA) reported yesterday that an assessment of 642,000 miles of rivers and streams showed 34 percent in less than good condition. In a major study of the Clean Water Act, the Natural Resources Defense Council last fall reported that poison runoff impairs损害more than 125,000 miles of rivers.More recently, the NRDC and Izaak Walton League warned that pollution and loss of wetlands—made worse by last year’s flooding—is degrading恶化the Mississippi River ecosystem.On Tuesday, the conservation group保护组织American Rivers issued its annual list of 10 ―endangered‖ and 20 ―threatened‖ rivers in 32 states, the District of Colombia, and Canada.At the top of the list is the Clarks Fork of the Yellowstone River, whereCanadian mining firms plan to build a 74-acre英亩reservoir水库，蓄水池as part of a gold mine less than three miles from Yellowstone National Park. The reservoir would hold the runoff from the sulfuric acid 硫酸used to extract gold from crushed rock.―In the event this tailings pond failed, the impact to th e greater Yellowstone ecosystem would be cataclysmic大变动的，灾难性的and the damage irreversible不可逆转的.‖ Sen. Max Baucus of Montana, chairman of the Environment and Public Works Committee, wrote to Noranda Minerals Inc., an owner of the ― New World Mine‖.Last fall, an EPA official expressed concern about the mine and its potential impact, especially the plastic-lined storage reservoir. ― I am unaware of any studies evaluating how a tailings pond尾矿池，残渣池could be maintained to ensure its structural integrity forev er,‖ said Stephen Hoffman, chief of the EPA’s Mining Waste Section. ―It is my opinion that underwater disposal of tailings at New World may present a potentially significant threat to human health and the environment.‖The results of an environmental-impact statement, now being drafted by the Forest Service and Montana Department of State Lands, could determine the mine’s future…In its recent proposal to reauthorize the Clean Water Act, the Clinton administration noted ―dramatically improved water quality since 1972,‖ when the act was passed. But it also reported that 30 percent of riverscontinue to be degraded, mainly by silt泥沙and nutrients from farm and urban runoff, combined sewer overflows, and municipal sewage城市污水. Bottom sediments沉积物are contaminated污染in more than 1,000 waterways, the administration reported in releasing its proposal in January. Between 60 and 80 percent of riparian corridors (riverbank lands) have been degraded.As with endangered species and their habitats in forests and deserts, the complexity of ecosystems is seen in rivers and the effects of development----beyond the obvious threats of industrial pollution, municipal waste, and in-stream diversions改道to slake消除the thirst of new communities in dry regions like the Southwes t…While there are many political hurdles障碍ahead, reauthorization of the Clean Water Act this year holds promise for US rivers. Rep. Norm Mineta of California, who chairs the House Committee overseeing the bill, calls it ―probably the most important env ironmental legislation this Congress will enact.‖ (553 words)6.According to the passage, the Clean Water Act______.A.has been ineffectiveB.will definitely be renewedC.has never been evaluatedD.was enacted some 30 years ago7.“Endangered” rivers are _________.A.catalogued annuallyB.less polluted than ―threatened rivers‖C.caused by floodingD.adjacent to large cities8.The “cataclysmic” event referred to in paragraph eight would be__________.A. fortuitous偶然的，意外的B. adventitious外加的，偶然的C. catastrophicD. precarious不稳定的，危险的9. The owners of the New World Mine appear to be______.A. ecologically aware of the impact of miningB. determined to construct a safe tailings pondC. indifferent to the concerns voiced by the EPAD. willing to relocate operations10. The passage conveys the impression that_______.A. Canadians are disinterested in natural resourcesB. private and public environmental groups aboundC. river banks are erodingD. the majority of US rivers are in poor conditionText CA classic series of experiments to determine the effects ofoverpopulation on communities of rats was reported in February of 1962 in an article in Scientific American. The experiments were conducted by a psychologist, John B. Calhoun and his associates. In each of these experiments, an equal number of male and female adult rats were placed in an enclosure and given an adequate supply of food, water, and other necessities. The rat populations were allowed to increase. Calhoun knew from experience approximately how many rats could live in the enclosures without experiencing stress due to overcrowding. He allowed the population to increase to approximately twice this number. Then he stabilized the population by removing offspring that were not dependent on their mothers. He and his associates then carefully observed and recorded behavior in these overpopulated communities. At the end of their experiments, Calhoun and his associates were able to conclude that overcrowding causes a breakdown in the normal social relationships among rats, a kind of social disease. The rats in the experiments did not follow the same patterns of behavior as rats would in a community without overcrowding.The females in the rat population were the most seriously affected by the high population density: They showed deviant异常的maternal behavior; they did not behave as mother rats normally do. In fact, many of the pups幼兽，幼崽, as rat babies are called, died as a result of poor maternal care. For example, mothers sometimes abandoned their pups,and, without their mothers' care, the pups died. Under normal conditions, a mother rat would not leave her pups alone to die. However, the experiments verified that in overpopulated communities, mother rats do not behave normally. Their behavior may be considered pathologically 病理上，病理学地diseased.The dominant males in the rat population were the least affected by overpopulation. Each of these strong males claimed an area of the enclosure as his own. Therefore, these individuals did not experience the overcrowding in the same way as the other rats did. The fact that the dominant males had adequate space in which to live may explain why they were not as seriously affected by overpopulation as the other rats. However, dominant males did behave pathologically at times. Their antisocial behavior consisted of attacks on weaker male,female, and immature rats. This deviant behavior showed that even though the dominant males had enough living space, they too were affected by the general overcrowding in the enclosure.Non-dominant males in the experimental rat communities also exhibited deviant social behavior. Some withdrew completely; they moved very little and ate and drank at times when the other rats were sleeping in order to avoid contact with them. Other non-dominant males were hyperactive; they were much more active than is normal, chasing other rats and fighting each other. This segment of the rat population, likeall the other parts, was affected by the overpopulation.The behavior of the non-dominant males and of the other components of the rat population has parallels in human behavior. People in densely populated areas exhibit deviant behavior similar to that of the rats in Calhoun's experiments. In large urban areas such as New York City, London, Mexican City, and Cairo, there are abandoned children. There are cruel, powerful individuals, both men and women. There are also people who withdraw and people who become hyperactive. The quantity of other forms of social pathology such as murder, rape, and robbery also frequently occur in densely populated human communities. Is the principal cause of these disorders overpopulation? Calhoun’s experiments suggest that it might be. In any case, social scientists and city planners have been influenced by the results of this series of experiments.11. Paragraph l is organized according to__________.A. reasonsB. descriptionC. examplesD. definition12．Calhoun stabilized the rat population_________.A. when it was double the number that could live in the enclosure without stressB. by removing young ratsC. at a constant number of adult rats in the enclosureD. all of the above are correct13.W hich of the following inferences CANNOT be made from theinformation inPara. 1?A. Calhoun's experiment is still considered important today.B. Overpopulation causes pathological behavior in rat populations.C. Stress does not occur in rat communities unless there is overcrowding.D. Calhoun had experimented with rats before.14. Which of the following behavior didn‟t happen in this experiment?A. All the male rats exhibited pathological behavior.B. Mother rats abandoned their pups.C. Female rats showed deviant maternal behavior.D. Mother rats left their rat babies alone.15. The main idea of the paragraph three is that __________.A. dominant males had adequate living spaceB. dominant males were not as seriously affected by overcrowding as the otherratsC. dominant males attacked weaker ratsD. the strongest males are always able to adapt to bad conditionsText DThe first mention of slavery in the statutes法令，法规of the English colonies of North America does not occur until after 1660—some forty years after the importation of the first Black people. Lest we think that existed in fact before it did in law, Oscar and Mary Handlin assure us, that the status of B lack people down to the 1660’s was that of servants. A critique批判of the Handlins’ interpretation of why legal slavery did not appear until the 1660’s suggests that assumptions about the relation between slavery and racial prejudice should be reexamined, and that explanation for the different treatment of Black slaves in North and South America should be expanded.The Handlins explain the appearance of legal slavery by arguing that, during the 1660’s, the position of white servants was improving relative to that of black servants. Thus, the Handlins contend, Black and White servants, heretofore treated alike, each attained a different status. There are, however, important objections to this argument. First, the Handlins cannot adequately demonstrate that t he White servant’s position was improving, during and after the 1660’s; several acts of the Maryland and Virginia legislatures indicate otherwise. Another flaw in the Handlins’ interpretation is their assumption that prior to the establishment of legal slavery there was no discrimination against Black people. It is true that before the 1660’s Black people were rarely called slaves. But this shouldnot overshadow evidence from the 1630’s on that points to racial discrimination without using the term slavery. Such discrimination sometimes stopped short of lifetime servitude or inherited status—the two attributes of true slavery—yet in other cases it included both. The Handlins’ argument excludes the real possibility that Black people in the English colonies were never treated as the equals of White people.The possibility has important ramifications后果，影响.If from the outset Black people were discriminated against, then legal slavery should be viewed as a reflection and an extension of racial prejudice rather than, as many historians including the Handlins have argued, the cause of prejudice. In addition, the existence of discrimination before the advent of legal slavery offers a further explanation for the harsher treatment of Black slaves in North than in South America. Freyre and Tannenbaum have rightly argued that the lack of certain traditions in North America—such as a Roman conception of slavery and a Roman Catholic emphasis on equality— explains why the treatment of Black slaves was more severe there than in the Spanish and Portuguese colonies of South America. But this cannot be the whole explanation since it is merely negative, based only on a lack of something. A more compelling令人信服的explanation is that the early and sometimes extreme racial discrimination in the English colonies helped determine the particular nature of the slavery that followed. (462 words)16. Which of the following is the most logical inference to be drawn from the passage about the effects of “several acts of the Maryland and Virginia legislatures” (Para.2) passed during and after the 1660‟s?A. The acts negatively affected the pre-1660’s position of Black as wellas of White servants.B. The acts had the effect of impairing rather than improving theposition of White servants relative to what it had been before the 1660’s.C. The acts had a different effect on the position of white servants thandid many of the acts passed during this time by the legislatures of other colonies.D. The acts, at the very least, caused the position of White servants toremain no better than it had been before the 1660’s.17. With which of the following statements regarding the status ofBlack people in the English colonies of North America before the 1660‟s would the author be LEAST likely to agree?A. Although black people were not legally considered to be slaves,they were often called slaves.B. Although subject to some discrimination, black people had a higherlegal status than they did after the 1660’s.C. Although sometimes subject to lifetime servitude, black peoplewere not legally considered to be slaves.D. Although often not treated the same as White people, black people,like many white people, possessed the legal status of servants.18. According to the passage, the Handlins have argued which of thefollowing about the relationship between racial prejudice and the institution of legal slavery in the English colonies of North America?A. Racial prejudice and the institution of slavery arose simultaneously.B. Racial prejudice most often the form of the imposition of inheritedstatus, one of the attributes of slavery.C. The source of racial prejudice was the institution of slavery.D. Because of the influence of the Roman Catholic Church, racialprejudice sometimes did not result in slavery.19. The passage suggests that the existence of a Roman conception ofslavery in Spanish and Portuguese colonies had the effect of _________.A. extending rather than causing racial prejudice in these coloniesB. hastening the legalization of slavery in these colonies.C. mitigating some of the conditions of slavery for black people in these coloniesD. delaying the introduction of slavery into the English colonies20. The author considers the explanation put forward by Freyre andTannenbaum for the treatment accorded B lack slaves in the English colonies of North America to be _____________.A. ambitious but misguidedB. valid有根据的but limitedC. popular but suspectD. anachronistic过时的，时代错误的and controversialUNIT 2Text AThe sea lay like an unbroken mirror all around the pine-girt, lonely shores of Orr’s Island. Tall, kingly spruce s wore their regal王室的crowns of cones high in air, sparkling with diamonds of clear exuded gum流出的树胶; vast old hemlocks铁杉of primeval原始的growth stood darkling in their forest shadows, their branches hung with long hoary moss久远的青苔;while feathery larches羽毛般的落叶松,turned to brilliant gold by autumn frosts, lighted up the darker shadows of the evergreens. It was one of those hazy朦胧的, calm, dissolving days of Indian summer, when everything is so quiet that the fainest kiss of the wave on the beach can be heard, and white clouds seem to faint into the blue of the sky, and soft swathing一长条bands of violet vapor make all earth look dreamy, and give to the sharp, clear-cut outlines of the northern landscape all those mysteries of light and shade which impart such tenderness to Italian scenery.The funeral was over,--- the tread鞋底的花纹/ 踏of many feet, bearing the heavy burden of two broken lives, had been to the lonely graveyard, and had come back again,--- each footstep lighter and more unconstrained不受拘束的as each one went his way from the great old tragedy of Death to the common cheerful of Life.The solemn black clock stood swaying with its eternal ―tick-tock, tick-tock,‖ in the kitchen of the brown house on Orr’s Island. There was there that sense of a stillness that can be felt,---such as settles down on a dwelling住处when any of its inmates have passed through its doors for the last time, to go whence they shall not return. The best room was shut up and darkened, with only so much light as could fall through a little heart-shaped hole in the window-shutter,---for except on solemn visits, or prayer-meetings or weddings, or funerals, that room formed no part of the daily family scenery.The kitchen was clean and ample, hearth灶台, and oven on one side, and rows of old-fashioned splint-bottomed chairs against the wall. A table scoured to snowy whiteness, and a little work-stand whereon lay the Bible, the Missionary Herald, and the Weekly Christian Mirror, before named, formed the principal furniture. One feature, however, must not be forgotten, ---a great sea-chest水手用的储物箱,which had been the companion of Zephaniah through all the countries of the earth. Old, and battered破旧的，磨损的, and unsightly难看的it looked, yet report said that there was good store within which men for the most part respect more than anything else; and, indeed it proved often when a deed of grace was to be done--- when a woman was suddenly made a widow in a coast gale大风，狂风, or a fishing-smack小渔船was run down in the fogs off the banks, leaving in some neighboring cottage a family of orphans,---in all such cases, the opening of this sea-chest was an event of good omen 预兆to the bereaved丧亲者;for Zephaniah had a large heart and a large hand, and was apt有…的倾向to take it out full of silver dollars when once it went in. So the ark of the covenant约柜could not have been looked on with more reverence崇敬than the neighbours usually showed to Captain Pennel’s sea-chest.1. The author describes Orr‟s Island in a(n)______way.A.emotionally appealing, imaginativeB.rational, logically preciseC.factually detailed, objectiveD.vague, uncertain2.According to the passage, the “best room”_____.A.has its many windows boarded upB.has had the furniture removedC.is used only on formal and ceremonious occasionsD.is the busiest room in the house3.From the description of the kitchen we can infer that thehouse belongs to people who_____.A.never have guestsB.like modern appliancesC.are probably religiousD.dislike housework4.The passage implies that_______.A.few people attended the funeralB.fishing is a secure vocationC.the island is densely populatedD.the house belonged to the deceased5.From the description of Zephaniah we can see thathe_________.A.was physically a very big manB.preferred the lonely life of a sailorC.always stayed at homeD.was frugal and saved a lotText BBasic to any understanding of Canada in the 20 years after the Second World War is the country' s impressive population growth. For every three Canadians in 1945, there were over five in 1966. In September 1966 Canada's population passed the 20 million mark. Most of this surging growth came from natural increase. The depression of the 1930s and the war had held back marriages, and the catching-up process began after 1945. The baby boom continued through the decade of the 1950s, producing a population increase of nearly fifteen percent in the five years from 1951 to 1956. This rate of increase had been exceeded only once before in Canada's history, in the decade before 1911 when the prairies were being settled. Undoubtedly, the good economic conditions of the 1950s supported a growth in the population, but the expansion also derived from a trend toward earlier marriages and an increase in the average size of families; In 1957 the Canadian birth rate stood at 28 per thousand, one of the highest in the world. After the peak year of 1957, thebirth rate in Canada began to decline. It continued falling until in 1966 it stood at the lowest level in 25 years. Partly this decline reflected the low level of births during the depression and the war, but it was also caused by changes in Canadian society. Young people were staying at school longer, more women were working; young married couples were buying automobiles or houses before starting families; rising living standards were cutting down the size of families. It appeared that Canada was once more falling in step with the trend toward smaller families that had occurred all through theWestern world since the time of the Industrial Revolution. Although the growth in Canada’s population had slowed down by 1966 (the cent), another increase in the first half of the 1960s was only nine percent), another large population wave was coming over the horizon. It would be composed of the children of the children who were born during the period of the high birth rate prior to 1957.6. What does the passage mainly discuss?A. Educational changes in Canadian society.B. Canada during the Second World War.C. Population trends in postwar Canada.D. Standards of living in Canada.7. According to the passage, when did Canada's baby boom begin?A. In the decade after 1911.B. After 1945.C. During the depression of the 1930s.D. In 1966.8. The author suggests that in Canada during the 1950s____________.A. the urban population decreased rapidlyB. fewer people marriedC. economic conditions were poorD. the birth rate was very high9. When was the birth rate in Canada at its lowest postwar level?A. 1966.B. 1957.C. 1956.D. 1951.10. The author mentions all of the following as causes of declines inpopulation growth after 1957 EXCEPT_________________.A. people being better educatedB. people getting married earlierC. better standards of livingD. couples buying houses11.I t can be inferred from the passage that before the IndustrialRevolution_______________.A. families were largerB. population statistics were unreliableC. the population grew steadilyD. economic conditions were badText CI was just a boy when my father brought me to Harlem for the first time, almost 50 years ago. We stayed at the hotel Theresa, a grand brick structure at 125th Street and Seventh avenue. Once, in the hotel restaurant, my father pointed out Joe Louis. He even got Mr. Brown, the hotel manager, to introduce me to him, a bit punchy强力的but still champ焦急as fast as I was concerned.Much has changed since then. Business and real estate are booming. Some say a new renaissance is under way. Others decry责难what they see as outside forces running roughshod肆意践踏over the old Harlem. New York meant Harlem to me, and as a young man I visited it whenever I could. But many of my old haunts are gone. The Theresa shut down in 1966. National chains that once ignored Harlem now anticipate yuppie money and want pieces of this prime Manhattan real estate. So here I am on a hot August afternoon, sitting in a Starbucks that two years ago opened a block away from the Theresa, snatching抓取，攫取at memories between sips of high-priced coffee. I am about to open up a piece of the old Harlem---the New York Amsterdam News---when a tourist。

动刚度的英语

动刚度的英语Stiffness is an important mechanical property that characterizes the resistance of a material to deformation when a force is applied. In engineering and materials science, the concept of stiffness plays a crucial role in the design and analysis of structures, components, and materials. In this article, we will explore the concept of stiffness, its significance, and its applications in various fields.Stiffness, also known as rigidity, is the ability of a material to resist deformation in response to an applied force. It is a measure of how much a material will deform under a given load. The stiffness of a material is typically described by its elastic modulus, which is a measure of the material's resistance to deformation. The higher the elastic modulus, the stiffer the material.The concept of stiffness is fundamental in engineering and materials science. In structural engineering, stiffness is a critical factor in the design and analysis of buildings, bridges, and other infrastructure. The stiffness of a structure determines its ability to withstand loads and forces without excessive deformation. In mechanical engineering, stiffness is essential in the design of machine components and mechanisms. It ensures that the components can withstand the forces and loads they are subjected to during operation.In materials science, stiffness is an important property in the characterization of materials. It is used to assess the performance of materials in various applications, such as in the aerospace, automotive, and construction industries. Stiffness is also a key consideration in the selection of materials for specific applications, as it directly impacts the performance and durability of the final product.One of the most common ways to measure stiffness is through tensile testing, where a material is subjected to an axial load to determine its response to stress. The resulting stress-strain curve provides valuable information about the material's stiffness and elastic behavior. Another method for assessing stiffness is through the use of non-destructivetesting techniques, such as ultrasound and resonance testing, which can provide insights into the stiffness and integrity of materials without causing damage.The significance of stiffness extends beyond the realm of engineering and materials science. In biomechanics, stiffness is a critical parameter in the study of the mechanical properties of biological tissues and structures. It is used to understand the behavior of bones, muscles, and connective tissues, and is essential in the design of prosthetics and medical devices.In conclusion, stiffness is a fundamental concept in engineering, materials science, and biomechanics. It plays a crucial role in the design, analysis, and characterization of materials, structures, and biological tissues. Understanding and controlling stiffness is essential in the development of new materials, the design of innovative structures, and the advancement of medical technology. As we continue to push the boundaries of engineering and science, the concept of stiffness will remain a cornerstone in the pursuit of new and groundbreaking innovations.。

自考《现代语言学》复习题及答案

自考《现代语言学》复习题及答案2017年自考《现代语言学》复习题及答案一、单项选择1. Which of the following sounds is a voiceless bilabial stop?A. [p]B. [b]C. [m]D. [t]2. The great source of modification of the air stream is found in the ______ cavity.A. nasalB. oralC. lungD. glottis3. ______ act is the act performed by or resulting from saying something.A. A locutionaryB. An illocutionaryC. A perlocutionaryD. A speech4. Once the notion of ______ was taken into consideration, semantics spilled into pragmatics.A. meaningB. contextC. formD. content5. Sense is concerned with the ______ meaning of the linguistic form.A. contextualB. realC. behavioristD. inherent6. Hyponyms of the same ______ are co-hyponyms.A. wordB. lexical itemC. superordinateD. hyponym7. Words that are opposite in meaning are ______.A. synonymsB. hyponymsC. antonymsD. homophones8. The word “modernizers” is composed of _____ morphemes.A. 3B. 4C. 5D. 69. According to F. de Saussure, _____ refers to the abstract linguistic system shared by all the members of a speech community.A. paroleB. performanceC. langueD. language10. Language is arbitrary in that there is no logical connection between meanings and ______.A. wordsB. soundsC. objectsD. ideas11. ______ morphemes are those that cannot be used independently but have to be combined with other morphemes, either free or bound, to form a word.A. FreeB. BoundC. RootD. Affix12. The smallest meaningful unit of language is ______.A. rootB. affixC. stemD. morpheme13. _____ refers to a word or expression that is prohibited by the “polite” society from general use.A. Linguistic tabooB. EuphemismC. Address termD. Slang14. Lying under the skull, the human brain contains an average of the ten billion nerve cells called ______.A. neuronsB. nerve systemC. nervesD. cerebral cortex15. ______ language belongs to the Sino-Tibetan Family.A. EnglishB. SpanishC. IndianD. Chinese参考答案：1--- 5ABCBD 6---10CCBCB 11---15BDAAD二、名词解释 (每个2分，共20 分)1. Linguistics is generally defined as the scientific study of language.2. Morphology is a branch of grammar which studies the internal structure of words and the rules by which words are formed.3. Reference means what a linguistic form refers to in the real physical world; it deals with the relationship between the linguistic element and the non-linguistic world of experience.4. An illocutionary act is the act of expressing the speaker’s intention; it is the act performing is saying something.5. Speech community is thus defined as a group of people who form a community (which may have few members as a family or as many members as a country), and share the same language or a particular variety of language.6. Language is a system of arbitrary vocal symbols used for human communication.7. Inflectional affixes or inflectional morphemes manifest various grammatical relations or grammatical categories such as number, tense, degree, and case.8. Pragmatics is the study of how speakers of language use sentences to effect successful communication.9. Accent refers to a way of pronunciation which tells the listener something about the speaker’s regional or social background.10. A lingua franca is a variety of language that serves as a medium of communication among groups of people from diverse linguistic backgrounds.三、简答题(每小题5分，共20分)1. What is the distinction between competence andperformance?Competence and performance was proposed by the American linguist N. Chomsky in the la te 1950’s. Chomsky defines competence as the ideal user’s knowledge of the rules of his language, and performance the actual realization of this knowledge in linguistic communication.2. What are the sense relations between sentences?Sense relations between sentences:1) X is synonymous with Y.2) X is inconsistent with Y.3) X entails Y.(Y is an entailment of X.)4) X presupposes Y. (Y is a prerequisite of X)5) X is a contradiction.6) X is semantically anomalous.3. What is idiolect?When an individual speaks, what is actually produced is a unique language system of the speaker, expressed within the overall system of a particular language. Such a personal dialect is referred to as idiolect.4. What is the Sapir-Whorf hypothesis?Sapir-Whorf proposed first that all higher levels of thinking are dependent on language. Or put it more bluntly, language determines thought, hence the strong notion of linguistic determinism. Because languages differ in many ways, Whorf also believed that speakers of different languages perceive and experience the world differently, that is, relative to their linguistic background, hence the notion of linguistic relativism. In short, the strong version of the Sapir-Whorf hypothesis proposes that the language we speak determines the way we perceive the world and therefore the nature of thought.四、论述题(每小题10分，共30分)1. What are the design features of language?Design features refer to the defining properties of human language that distinguish it from any animal system of communication.1) arbitrariness2) productivity3) duality4) displacement5) cultural transmission2. Draw a labeled constituent structure tree diagram for each of the following sentences:1) The student likes the new linguistics professor.2) John suggested Mary take the linguistics class.1. The student likes the new linguistics professor.2. John suggested (that) Mary take the linguistics class.3. What is the difference between acquisition and learning? Illustrate with examples.Acquisition refers to the gradual and subconscious development of ability in the first language by using it naturally in daily communicative situations. Learning, however, is defined as a conscious process of accumulating knowledge of a second language usually obtained in school settings. It is recognized that children acquire their native language without explicit learning.A second language is more commonly learned but to some degree may also be acquired, depending on the environmental setting and the input received by the L2 learner.【2017年自考《现代语言学》复习题及答案】。

characterization results -回复

characterization results -回复[characterization results]Characterization results, as the name implies, refer to the outcomes or findings obtained from the process of characterizing something or someone. Characterization is the act of describing or analyzing the qualities, traits, or features of a particular entity. It often involves thorough observation, analysis, and interpretation to determine the true nature or essence of the subject being characterized.From scientific research to literature and even everyday life, various fields employ characterization to gain a better understanding of different entities in their respective contexts. By examining and evaluating certain characteristics, researchers, scholars, and individuals can draw meaningful conclusions or make informed decisions.To explore the concept of characterization results further, we can consider the steps involved in achieving such outcomes:1. Identify the subject: The initial step in obtaining characterizationresults is to identify the subject of analysis. This could be an object, person, phenomenon, or even an abstract idea. The subject must be clearly defined, allowing for a focused and comprehensive characterization process.2. Collect relevant data: Next, collect relevant data or information about the subject. Depending on the context, this data collection process may involve conducting experiments, surveys, interviews, observations, or literature reviews. The aim is to gather as much pertinent information as possible to commence the characterization process.3. Analyze and interpret: Once the data is collected, it must be analyzed and interpreted. This step involves examining the information and identifying patterns, trends, or correlations. Data analysis techniques such as statistical analysis, qualitative analysis, or content analysis may be employed to extract meaningful insights.4. Identify key characteristics: Based on the analysis and interpretation, key characteristics of the subject under study should be identified. These could be physical attributes, behavioralpatterns, psychological traits, or any other relevant features. The identification of key characteristics is crucial as they form the basis for the subsequent steps of the characterization process.5. Compare and contrast: At this stage, the identified characteristics are compared and contrasted with existing knowledge or theories. This step helps to validate the findings and make connections with the broader understanding of the subject matter. Comparing and contrasting also aids in identifying any unique or noteworthy aspects of the subject being characterized.6. Draw conclusions: Drawing conclusions is an important outcome of the characterization process. It involves synthesizing the analyzed data, identified characteristics, and any insights gained along the way. These conclusions should be based on evidence and logical reasoning, providing a clear understanding of the subject and its qualities.7. Communicate the results: Finally, the results of the characterization process need to be effectively communicated to the intended audience. This could be in the form of research papers, reports, presentations, or any other suitable means ofdissemination. Clear and concise communication of results is essential for others to grasp the essence of the subject being characterized and its significance.In conclusion, characterization results are the outcomes obtained through the process of characterizing something or someone. By following the steps of identification, data collection, analysis, interpretation, identification of key characteristics, comparison and contrast, drawing conclusions, and effective communication of results, an accurate and comprehensive understanding of the subject can be achieved. Characterization results play a vital role in various fields, from scientific research to literature, and enable us to make informed decisions, gain new insights, and contribute to the collective understanding of the world around us.。

中国式谈话的特点英语作文

Chinese conversational style is unique and reflects the cultural values and social norms of the country.Here are some key characteristics of Chinese conversation:1.Indirectness:Chinese people often prefer to express their opinions and feelings in an indirect manner.This is to avoid potential conflicts and to maintain harmony in the conversation.2.Politeness and Respect:Showing respect to elders and superiors is a fundamental aspect of Chinese culture.This is reflected in the language used during conversations, where honorifics and polite expressions are common.e of Metaphors and Idioms:Chinese conversations often include the use of metaphors and idioms,which are rich in cultural significance and can convey complex ideas succinctly.4.Contextual Understanding:The Chinese language relies heavily on context to understand the meaning of words and phrases.This can sometimes make conversations challenging for nonnative speakers,as the literal translation may not convey the intended meaning.5.Emphasis on Relationships Guanxi:Building and maintaining relationships is an important part of Chinese society.Conversations often revolve around establishing and strengthening these relationships.6.Avoidance of Direct Rejection:To maintain face,Chinese people may avoid giving a direct no in response to a request.Instead,they might use phrases that imply refusal without directly stating it.7.Nonverbal Communication:Body language,facial expressions,and tone of voice playa significant role in Chinese conversations.Understanding these nonverbal cues can provide deeper insight into the conversation.8.Hierarchical Structure:Conversations often reflect the hierarchical structure of Chinese society,with respect and deference shown to those in higher positions.e of Rhetorical Questions:Rhetorical questions are used not only for emphasis but also as a way to indirectly suggest an opinion or course of action.10.Saving Face:The concept of face is crucial in Chinese culture.Conversations are often conducted in a way that allows all parties to save face,even if disagreements arise.11.Pace and Timing:The pace of a conversation can vary,and there may be pauses or silences that are used to gather thoughts or to subtly communicate a point.e of Humor:Humor is often used to diffuse tension,to build rapport,or to make a point in a nonconfrontational way.Understanding these characteristics can help in navigating and appreciating the nuances of Chinese conversations,which are deeply rooted in the countrys rich history and cultural heritage.。

219525849_酪蛋白酸钠-甘油二酯软奶酪的制备及其特性分析

韩艳萍，郭星磊，周玲，等. 酪蛋白酸钠-甘油二酯软奶酪的制备及其特性分析[J]. 食品工业科技，2023，44（14）：1−8. doi:10.13386/j.issn1002-0306.2022100260HAN Yanping, GUO Xinglei, ZHOU Ling, et al. Preparation and Characterization of Sodium Caseinate-Glycerol Diester Soft Cheese[J]. Science and Technology of Food Industry, 2023, 44(14): 1−8. (in Chinese with English abstract). doi: 10.13386/j.issn1002-0306.2022100260· 青年编委专栏—食品营养素包埋与递送（客座主编：黄强、蔡杰、陈帅） ·酪蛋白酸钠-甘油二酯软奶酪的制备及其特性分析韩艳萍，郭星磊，周　玲，许　婧，苏菁菁，周子旋，韩　阳，王菊花，薛秀恒*（安徽农业大学茶与食品科技学院，安徽合肥 230036）摘　要：目的：探究以酪蛋白酸钠（Sodium caseinate ，SC ）与纳米纤维素（Nano-crystalline cellulose ，NCC ）为壁材包埋甘油二酯（Diacylglycerol ，DAG ）的条件，改善开发功能性发酵乳制品品质。

方法：以乳脂为原料，通过酶解反应制备出DAG ，以SC 与NCC 为壁材制备水包油型DAG 乳液，筛选乳液最佳制备条件下的SC 和NCC 添加量、粒径大小、均质压力，以及对添加了DAG 纳米乳液的软奶酪进行流变分析、质构分析和感官分析，探究它们之间的稳定性差异，并作为脂肪替代物制备软奶酪。

结果：采用高压均质法制备酪蛋白酸钠复合纤维素甘油二酯乳液的最佳条件为：NCC 含量1.5%，SC 含量5%，芯壁比1:1，均质压力100 MPa ，此时DAG 乳液均为水包油型，粒径大小在100~240 nm 之间。

characterized interactions -回复

characterized interactions -回复Characterized interactions refer to the various forms of exchanges and relationships between individuals, groups, or even countries that are marked by distinct traits or qualities. These interactions can take place in various spheres of life, such as personal, social, economic, or political. In this article, we will explore the concept of characterized interactions and provide a step-by-step analysis of their different aspects.Step 1: Understanding Characterized Interactions Characterized interactions are essentially interactions that are distinguished by specific traits or features. These traits can include the nature of the relationship, the intensity of the interaction, the purpose or goal of the interaction, and the impact it has on the parties involved.Step 2: Types of Characterized InteractionsThere are numerous types of characterized interactions, depending on the context in which they occur. Some common types include: 1. Personal interactions: These interactions occur between individuals on a personal level, such as family members, friends, or romantic partners. They are characterized by emotional closeness,trust, and shared experiences.2. Social interactions: These interactions occur within a society or community and can be both formal and informal. Examples include interactions at social gatherings, in educational institutions, or at workplaces. They are characterized by social norms, expectations, and hierarchies.3. Economic interactions: These interactions occur in the realm of business and trade. They involve transactions, negotiations, and collaborations between individuals, companies, or even countries. They are characterized by economic motives, competition, and mutual benefits.4. Political interactions: These interactions take place in the political arena and involve interactions between governments, political parties, or international organizations. They are characterized by power dynamics, diplomacy, and negotiation.Step 3: Factors Influencing the Characterization of Interactions Several factors can influence the characterization of interactions. These factors can shape the nature, intensity, and outcome of the interactions. Some key factors include:1. Culture: Cultural norms and values play a significant role in shaping interactions. Different cultures may prioritize differentvalues, such as individualism, collectivism, or hierarchy, which can impact the way interactions are conducted.2. Power dynamics: Power imbalances can significantly affect the characterization of interactions. Interactions between individuals or groups with unequal power may involve domination, oppression, or exploitation.3. Context: The context in which interactions take place, such as the environment, time, or specific circumstances, can have a significant impact on their characterization. For example, interactions during a crisis may be characterized by urgency or cooperation.4. Communication: Effective communication is crucial for successful interactions. The way information is exchanged, interpreted, and understood can shape the dynamics and outcomes of interactions.Step 4: Importance of Characterized Interactions Characterized interactions play a vital role in human society and have several important implications:1. Building relationships: Interpersonal interactions are essential for building and maintaining relationships. These interactions lay the foundation for trust, empathy, and mutual understanding.2. Social cohesion: Interactions within communities foster a sense of belonging and social cohesion. They allow individuals to bond,collaborate, and work towards common goals.3. Economic development: Economic interactions drive trade, innovation, and growth. They facilitate the exchange of goods, services, and knowledge, creating opportunities for economic development.4. Conflict resolution: Political interactions can be instrumental in resolving conflicts and fostering peace. Dialogue, negotiation, and diplomacy are essential tools in addressing differences and promoting cooperation.Step 5: Challenges in Characterized InteractionsWhile characterized interactions have significant benefits, they also face challenges that can hinder their effectiveness:1. Cultural differences: In a globalized world, interactions often involve individuals from diverse cultural backgrounds. These cultural differences can lead to misunderstandings or conflicts if not managed effectively.2. Power inequalities: Unequal power dynamics can create barriers to effective interactions. Marginalized groups may struggle to assert themselves or have their voices heard.3. Miscommunication: Inadequate communication can lead to misunderstandings, mistrust, or misinterpretation of intentions.Clear and effective communication is essential for successful interactions.4. Conflict of interests: Different parties may have conflicting interests or goals, leading to disagreements or competition. Effective negotiation and compromise are necessary to navigate these challenges.In conclusion, characterized interactions are a fundamental part of human life in various spheres, including personal, social, economic, and political. Understanding and effectively navigating these interactions require considering factors such as culture, power dynamics, context, and communication. While characterized interactions have several benefits, they also face challenges that need to be addressed for successful outcomes. By recognizing the importance of characterized interactions and actively working towards positive and inclusive interactions, individuals and societies can foster understanding, collaboration, and growth.。

基于光热效应和pH_响应性的聚多巴胺膜靶向纳米粒子的制备及性能评价

㊀基金项目:黑龙江省自然科学基金项目(Ｎｏ.ＬＨ２０２０Ｈ０９６㊁ＬＨ２０２１Ｈ１０２)作者简介:张翔珂ꎬ女ꎬ硕士生ꎬ研究方向:靶向及缓控释制剂ꎬＥ－ｍａｉｌ:１３１５７５９７３５＠ｑｑ.ｃｏｍ通信作者:阎雪莹ꎬ女ꎬ博士ꎬ教授ꎬ研究方向:靶向及缓控释制剂ꎬＴｅｌ:０４５１－８７２６６９０７ꎬＥ－ｍａｉｌ:ｙｙｙａｎｘｕｅｙｉｎｇ＠ｓｉｎａ.ｃｏｍ基于光热效应和ｐＨ响应性的聚多巴胺膜靶向纳米粒子的制备及性能评价张翔珂ꎬ高萌萌ꎬ陈铭ꎬ董雨萌ꎬ苏慧ꎬ阎雪莹(黑龙江中医药大学药学院ꎬ黑龙江哈尔滨１５００４０)摘要:目的㊀为构建高效㊁低毒㊁高肿瘤靶向性的乳腺癌给药系统ꎬ拟采用化疗与光疗相结合的治疗方法对乳腺癌进行治疗ꎮ方法㊀本文以盐酸吡柔比星和多西紫杉醇作为模型药物联合使用共同负载于介孔二氧化硅(ＭＳＮｓ)纳米粒内ꎬ利用盐酸多巴胺(ＰＤＡ)碱性条件下自身氧化在介孔二氧化硅表面形成聚多巴胺薄膜ꎬ最后通过酰胺化反应将活化后的叶酸修饰于盐酸多巴胺表面ꎬ最终制得双载药叶酸修饰聚多巴胺膜包覆的介孔二氧化硅纳米粒(ＦＡ－ＰＤＡ－ＴＨＰ－ＤＴＸ－ＭＳＮｓ)ꎮ结果㊀通过单因素考察最终确定介孔二氧化硅载药条件:载药溶剂为２５％乙醇水溶液㊁药物载体比为１ʒ１㊁载药时间为１２ｈꎻ盐酸多巴胺包覆条件:盐酸多巴胺浓度为０.５ｍｇｍＬ－１㊁搅拌时间为３ｈꎮ对双载药叶酸修饰聚多巴胺膜包覆的介孔二氧化硅纳米粒粒径㊁Ｚｅｔａ电位㊁傅立叶红外光谱等进行测定并与未进行修饰前介孔二氧化硅的数据进行比较ꎬ结果显示盐酸多巴胺和叶酸(ＦＡ)均成功修饰ꎮ测定最终成型的纳米粒ꎬ透射电镜下观察其形态为球形ꎬ大小均一ꎬ粒度分析仪测定结果显示ꎬ平均粒径为(２０１.４ʃ２１.７)ｎｍꎬＰＤＩ指数为０.２６４ꎬＺｅｔａ电位为(＋２３.３ʃ０.６７)ｍＶꎬ盐酸吡柔比星(ＴＨＰ)和多西紫杉醇Ｄ(ＤＴＸ)的载药量分别为(１１.７７％ʃ０.３３％)㊁(５.７２％ʃ０.２５％)ꎬＴＨＰ和ＤＴＸ的包封率分别为(３６.９２％ʃ０.４４％)㊁(３６.０２％ʃ０.６８％)ꎮ双载药叶酸修饰聚多巴胺膜包覆的介孔二氧化硅纳米粒给药系统体外释放实验结果显示双载药叶酸修饰聚多巴胺膜包覆的介孔二氧化硅纳米粒中药物具有良好的缓释性能和酸响应性并且在近红外激光的照射条件下能够实现药物的突释ꎮ结论㊀本研究可为聚多巴胺膜包覆双载药光热型纳米粒的抗肿瘤研究提供更加丰富的实验依据ꎬ为开发新型纳米粒奠定基础ꎮ关键词:聚多巴胺ꎻ盐酸吡柔比星ꎻ多西紫杉醇ꎻｐＨ响应ꎻ叶酸中图分类号:Ｒ９４３㊀文献标志码:Ａ㊀文章编号:２０９５－５３７５(２０２３)０７－０４６２－００９ｄｏｉ:１０.１３５０６/ｊ.ｃｎｋｉ.ｊｐｒ.２０２３.０７.００６Ｐｒｅｐａｒａｔｉｏｎａｎｄｉｎｖｉｔｒｏｐｈａｒｍａｃｏｄｙｎａｍｉｃｅｖａｌｕａｔｉｏｎｏｆｐｏｌｙｄｏｐａｍｉｎｅｍｅｍｂｒａｎｅ－ｔａｒｇｅｔｅｄｎａｎｏｐａｒｔｉｃｌｅｓｂａｓｅｄｏｎｐｈｏｔｏｔｈｅｒｍａｌｅｆｆｅｃｔａｎｄｐＨｒｅｓｐｏｎｓｉｖｅｎｅｓｓＺＨＡＮＧＸｉａｎｇｋｅꎬＧＡＯＭｅｎｇｍｅｎｇꎬＣＨＥＮＭｉｎｇꎬＤＯＮＧＹｕｍｅｎｇꎬＳＵＨｕｉꎬＹＡＮＸｕｅｙｉｎｇ(ＳｃｈｏｏｌｏｆＰｈａｒｍａｃｙꎬＨｅｉｌｏｎｇｊｉａｎｇＵｎｉｖｅｒｓｉｔｙｏｆＣｈｉｎｅｓｅＭｅｄｉｃｉｎｅꎬＨａｒｂｉｎ１５００４０ꎬＣｈｉｎａ)Ａｂｓｔｒａｃｔ:Ｏｂｊｅｃｔｉｖｅ㊀Ｉｎｏｒｄｅｒｔｏｃｏｎｓｔｒｕｃｔａｄｒｕｇｄｅｌｉｖｅｒｙｓｙｓｔｅｍｗｉｔｈｈｉｇｈｅｆｆｉｃｉｅｎｃｙꎬｌｏｗｔｏｘｉｃｉｔｙꎬａｎｄｈｉｇｈｔｕｍｏｒｔａｒｇｅｔｉｎｇꎬｔｈｅｃｏｍｂｉｎａｔｉｏｎｏｆｃｈｅｍｏｔｈｅｒａｐｙａｎｄｐｈｏｔｏｔｈｅｒａｐｙｗａｓｐｒｏｐｏｓｅｄｔｏｔｒｅａｔｂｒｅａｓｔｃａｎｃｅｒｉｎｔｈｉｓｅｘｐｅｒｉｍｅｎｔ.Ｍｅｔｈｏｄｓ㊀Ｉｎｔｈｉｓｐａｐｅｒꎬｐｉｒａｒｕｂｉｃｉｎｈｙｄｒｏｃｈｌｏｒｉｄｅ(ＴＨＰ)ａｎｄｄｏｃｅｔａｘｅｌ(ＤＴＸ)ｗｅｒｅｕｓｅｄａｓｍｏｄｅｌｄｒｕｇｓꎬｗｈｉｃｈｗｅｒｅｃｏ－ｌｏａｄｅｄｉｎｍｅｓｏｐｏｒｏｕｓｓｉｌｉｃａｎａｎｏｐａｒｔｉｃｌｅｓ(ＭＳＮｓ)ꎬａｎｄｓｅｌｆ－ｏｘｉｄａｔｉｏｎｏｆｄｏｐａｍｉｎｅｈｙｄｒｏｃｈｌｏｒｉｄｅｕｎｄｅｒａｌｋａｌｉｎｅｃｏｎｄｉｔｉｏｎｓｗａｓｕｓｅｄｔｏｆｏｒｍｐｏｌｙｓｔｙｒｅｎｅｏｎｔｈｅｓｕｒｆａｃｅｏｆＭＳＮｓ.Ｆｉｎａｌｌｙꎬｔｈｅａｃｔｉｖａｔｅｄｆｏｌｉｃａｃｉｄ(ＦＡ)ｗａｓｍｏｄｉｆｉｅｄｏｎｔｈｅｓｕｒｆａｃｅｏｆＰＤＡｂｙａｍｉｄａｔｉｏｎｒｅａｃｔｉｏｎꎬａｎｄｆｉｎａｌｌｙｄｏｕｂｌｅ－ｌｏａｄｅｄｆｏｌｉｃａｃｉｄ－ｍｏｄｉｆｉｅｄｐｏｌｙｄｏｐａｍｉｎｅｍｅｍｂｒａｎｅ－ｃｏａｔｅｄｍｅｓｏｐｏｒｏｕｓｓｉｌｉｃａｎａｎｏｐ￣ａｒｔｉｃｌｅｓ(ＦＡ－ＰＤＡ－ＴＨＰ－ＤＴＸ－ＭＳＮｓ)ｗｅｒｅｐｒｅｐａｒｅｄ.Ｒｅｓｕｌｔｓ㊀ＴｈｅｄｒｕｇｌｏａｄｉｎｇｃｏｎｄｉｔｉｏｎｓｏｆＭＳＮｓｗｅｒｅｄｅｔｅｒｍｉｎｅｄｂｙｓｉｎｇｌｅｆａｃｔｏｒｍｅｔｈｏｄ:ｔｈｅｄｒｕｇｌｏａｄｉｎｇｓｏｌｖｅｎｔｗａｓ２５％ｅｔｈａｎｏｌｓｏｌｕｔｉｏｎꎬｔｈｅｒａｔｉｏｏｆｄｒｕｇｃａｒｒｉｅｒｗａｓ１ʒ１ꎬａｎｄｔｈｅｄｒｕｇｌｏａｄ￣ｉｎｇｔｉｍｅｗａｓ１２ｈ.Ｔｈｅｃｏａｔｉｎｇｃｏｎｄｉｔｉｏｎｓｏｆｐｏｌｙｄｏｐａｍｉｎｅｍｅｍｂｒａｎｅｗｅｒｅａｓｆｏｌｌｏｗｓ:ｔｈｅｃｏｎｃｅｎｔｒａｔｉｏｎｏｆｄｏｐａｍｉｎｅｈｙｄｒｏ￣ｃｈｌｏｒｉｄｅｗａｓ０.５ｍｇｍＬ－１ａｎｄｔｈｅｓｔｉｒｒｉｎｇｔｉｍｅｗａｓ３ｈ.ＴｈｅｐａｒｔｉｃｌｅｓｉｚｅꎬＺｅｔａｐｏｔｅｎｔｉａｌａｎｄＦｏｕｒｉｅｒｔｒａｎｓｆｏｒｍｉｎｆｒａｒｅｄｓｐｅｃｔｒｏｓｃｏｐｙｏｆＦＡ－ＰＤＡ－ＴＨＰ－ＤＴＸ－ＭＳＮｓｗｅｒｅｄｅｔｅｒｍｉｎｅｄａｎｄｃｏｍｐａｒｅｄｗｉｔｈｔｈｏｓｅｏｆｕｎｍｏｄｉｆｉｅｄＭＳＮｓ.ＴｈｅｒｅｓｕｌｔｓｓｈｏｗｅｄｔｈａｔＰＤＡａｎｄｆｏｌｉｃａｃｉｄｗｅｒｅｍｏｄｉｆｉｅｄｓｕｃｃｅｓｓｆｕｌｌｙ.Ｔｈｅｃｈａｒａｃｔｅｒｉｚａｔｉｏｎｏｆｔｈｅｆｉｎａｌｆｏｒｍｅｄｎａｎｏｐａｒｔｉｃｌｅｓｗａｓｄｅｔｅｒ￣ｍｉｎｅｄꎬａｎｄｉｔｓｓｈａｐｅｗａｓｓｐｈｅｒｉｃａｌａｎｄｕｎｉｆｏｒｍｕｎｄｅｒｔｒａｎｓｍｉｓｓｉｏｎｅｌｅｃｔｒｏｎｍｉｃｒｏｓｃｏｐｅ.Ｔｈｅｒｅｓｕｌｔｓｏｆｐａｒｔｉｃｌｅｓｉｚｅａｎａｌｙｚｅｒｓｈｏｗｅｄｔｈａｔｔｈｅａｖｅｒａｇｅｐａｒｔｉｃｌｅｓｉｚｅｗａｓ(２０１.４ʃ２１.７)ｎｍꎬａｎｄｔｈｅＺｅｔａｐｏｔｅｎｔｉａｌｗａｓａｂｏｕｔ(＋２３.３ʃ０.６７)ｍＶ.ＴｈｅｄｒｕｇｌｏａｄｉｎｇｏｆＴＨＰａｎｄＤＴＸｗｅｒｅ１１.２５％ａｎｄ５.５７％ꎬｒｅｓｐｅｃｔｉｖｅｌｙ.ＴｈｅｅｎｃａｐｓｕｌａｔｉｏｎｅｆｆｉｃｉｅｎｃｉｅｓｏｆＴＨＰａｎｄＤＴＸｗｅｒｅ(３６.９２％ʃ０.４４％)ａｎｄ(３６.０２％ʃ０.６８％)ꎬｒｅｓｐｅｃｔｉｖｅｌｙ.ＴｈｅｒｅｓｕｌｔｓｏｆｄｒｕｇｒｅｌｅａｓｅｉｎｖｉｔｒｏｓｈｏｗｔｈａｔｔｈｅｄｒｕｇｉｎＦＡ－ＰＤＡ－ＴＨＰ－ＤＴＸ－ＭＳＮｓｈａｓｇｏｏｄｓｕｓｔａｉｎｅｄｒｅｌｅａｓｅｐｅｒｆｏｒｍａｎｃｅａｎｄａｃｉｄｒｅｓｐｏｎｓｅｐｅｒｆｏｒｍａｎｃｅꎬａｎｄｃａｎａｃｈｉｅｖｅｓｕｄｄｅｎｄｒｕｇｒｅｌｅａｓｅｕｎｄｅｒｔｈｅｃｏｎｄｉｔｉｏｎｏｆｎｅａｒ－ｉｎｆｒａｒｅｄｌａｓｅｒｉｒｒａｄｉａｔｉｏｎ.Ｃｏｎｃｌｕｓｉｏｎ㊀Ｉｔｃａｎｐｒｏｖｉｄｅｍｏｒｅａｂｕｎｄａｎｔｅｘｐｅｒｉｍｅｎｔａｌｂａｓｉｓｆｏｒｔｈｅｆｏｌｌｏｗ－ｕｐａｎｔｉ－ｔｕｍｏｒｒｅｓｅａｒｃｈｏｆｄｏｕｂｌｅ－ｌｏａｄｅｄｐｈｏｔｏｔｈｅｒｍａｌｎａｎｏｐａｒｔｉｃｌｅｓｃｏａｔｅｄｗｉｔｈｐｏｌｙｄｏｐａｍｉｎｅｆｉｌｍꎬａｎｄｌａｙａｆｏｕｎｄａｔｉｏｎｆｏｒｔｈｅｄｅｖｅｌｏｐｍｅｎｔｏｆｎｅｗｎａｎｏｐａｒｔｉｃｌｅｓ.Ｋｅｙｗｏｒｄｓ:ＰｏｌｙｄｏｐａｍｉｎｅꎻＰｉｒａｒｕｂｉｃｉｎｈｙｄｒｏｃｈｌｏｒｉｄｅꎻＤｏｃｅｔａｘｅｌꎻＰＨｒｅｓｐｏｎｓｅꎻＦｏｌｉｃａｃｉｄ㊀㊀化疗是治疗乳腺癌各个时期的重要治疗手段ꎬ为提高单一化疗药物的疗效ꎬ目前临床常将两种或多种化疗药物联合使用[１]ꎮ除此之外ꎬ还可将化疗与其他疗法相结合ꎬ例如光疗㊁免疫治疗等[２－３]ꎬ以提高对于肿瘤细胞的杀伤能力[４]ꎮ介孔二氧化硅纳米粒(ｍｅｓｏｐｏｒｏｕｓｓｉｌｉｃａｎａｎｏｐａｒｔｉｃｌｅｓꎬＭＳＮｓ)作为近些年来发展起来的一种新型无机介孔纳米材料[８]ꎬ具有比表面积大以及良好的生物相容性等优点ꎬ可在一定程度上增加药物的负载量ꎮ尽管ＭＳＮｓ具有多方面的优点ꎬ但是载药ＭＳＮｓ存在一定的药物突释风险ꎬ为此通常需要在ＭＳＮｓ表面上进行修饰ꎬ以实现对ＭＳＮｓ孔道的封堵ꎬ控制药物释放ꎮ聚多巴胺(ｐｏｌｙｄｏｐａｍｉｎｅꎬＰＤＡ)是盐酸多巴胺在碱性条件下氧化而形成的具有强大黏附性的仿生聚合物[９]ꎬ可以实现对ＭＳＮｓ表面覆盖ꎬ而在肿瘤部位的酸性环境中产生裂解ꎬ可防止ＭＳＮｓ孔道内药物在非肿瘤部位的突释ꎮＰＤＡ作为光热转化材料在近红外光区有强吸收性[１０]ꎬ经８０８ｎｍ近红外激光照射后可产生热能ꎬ当温度达到一定限度时ꎬ对肿瘤细胞产生杀伤作用ꎬ可实现化疗和光热治疗的联合作用[１１]ꎮ另外由于其表面存在着丰富的官能团易实现靶头的连接ꎬ可实现纳米粒的主动靶向作用[１２]ꎮ叶酸受体(ｆｏｌａｔｅｒｅｃｅｐｔｏｒｓꎬＦＲ)作为常用的肿瘤治疗的受体ꎬ在正常组织中的表达处于高度保守状态ꎬ而作为ＦＲ亚型之一的ＦＲ－α则在乳腺癌等上皮谱系肿瘤中过度表达[１３－１４]ꎬ因此ＦＲ－α可能成为乳腺癌的潜在治疗靶点ꎬ因此本研究选择叶酸作为纳米粒的靶头ꎮ为构建高效㊁低毒㊁高肿瘤靶向性的给药系统ꎬ本实验拟制备本实验中选择临床常见配伍方式蒽环类药物和微管抑制类药物中的代表药物盐酸吡柔比星(ｐｉｒａｒｕｂｉｃｉｎｈｙｄｒｏｃｈｌｏｒｉｄｅꎬＴＨＰ)[５]和多西紫杉醇(ｄｏｃｅｔａｘｅｌꎬＤＴＸ)[６－７]作为模型药ꎬ以ＦＲ－α为靶点ꎬ以包覆聚多巴胺的介孔二氧化硅为载体ꎬ将化疗与光疗相结合的纳米制剂对叶酸过表达型乳腺癌进行治疗ꎮ本试验中利用单因素考察对ＦＡ－ＰＤＡ－ＴＨＰ－ＤＴＸ－ＭＳＮｓ制备工艺进行优化ꎬ并对其形貌㊁光热效应㊁体外释放㊁体外药效学以及大鼠体内药代动力学进行了考察ꎮ从药剂学的角度为实现化疗与光疗相结合的靶向治疗方法提供了新的策略和依据ꎮ１㊀材料１.１㊀试剂与药品㊀多西紫杉醇(批号:Ｃ１２１６１８７９ꎬ上海麦克林生化科技有限公司)ꎻ盐酸吡柔比星[批号:Ａ２１１０３５８ꎬ凯梅根(上海)生物科技有限公司]ꎻ盐酸多巴胺(批号:Ｃ１１９５６７４０ꎬ上海麦克林生化科技有限公司)ꎻ三羟甲基氨基甲烷(批号:２０２１/０３ꎬ上海麦克林生化科技有限公司)ꎻ叶酸(批号:０８２０１７１００４ꎬ上海麦克林生化科技有限公司)ꎻＮ－羟基琥珀酰亚胺(批号:Ｃ１２９１３７９０ꎬ上海麦克林生化科技有限公司)ꎻ聚乙烯亚胺(批号:Ｃ１２４１７０９８ꎬ上海麦克林生化科技有限公司)ꎻ甲醇(色谱纯ꎬ美国迪马公司)ꎻ乙腈(色谱纯ꎬ美国迪马公司)ꎻ１－(３－二甲氨基丙基)－３乙基碳二甲胺(上海麦克林生化科技有限公司)ꎮ所有购买的试剂均未经进一步纯化直接使用ꎬ超纯水由水纯化系统(ＰＡＬＬＣａｓｃａｄｅＩＩＩ)制备ꎮ１.２㊀仪器㊀ＨＺＳ－ＨＡ恒温水浴振荡器(哈尔滨市东联电子技术开发有限公司)ꎻｅ２６９５高效液相色谱仪(美国Ｗａｔｅｒｓ公司)ꎻＬＲ－ＭＦＪ－８０８ｎｍ近红外激光器(长春镭锐光电科技有限公司)ꎻＮａｎｏ－ＺＳ９０纳米粒度及Ｚｅｔａ电位分析仪(马尔文仪器有限公司)ꎻ热电偶双通道测温器(东莞市希玛仪表有限公司)ꎻＡＳＡＰ２４６０全自动比表面及孔隙度分析仪(美国Ｍｉｃｒｏｍｅｒｉｔｉｃｓ公司)ꎻ粉末Ｘ射线衍射仪(德国布鲁克公司)ꎻＳＴＡ４４９Ｆ５同步热分析仪(德国耐驰公司)ꎻＦＥＩＴｅｃｎａｉＦ３０透射电子显微镜(美国ＦＥＩ公司)ꎮ２㊀试验方法与结果２.１㊀ＭＳＮｓ的制备㊀ＭＳＮ按照改进的Ｓｔöｂｅｒ方法合成[１５]并以酸化乙醇回流萃取法去除模板剂ꎮ具体操作如下:９０μＬ三乙醇胺(ＴＥＡ)与６０ｍＬＨ２Ｏ混合成稀的强碱溶液(ｐＨ＝９.５)ꎬ准确称量０.５０ｇ十六烷基三甲基溴化铵(ＣＴＡＢ)加入溶液中ꎬ９５ħ下磁力搅拌３０ｍｉｎ后缓慢滴加６１４μＬ正硅酸乙酯(ＴＥＯＳ)ꎬ在剧烈搅拌和恒温下反应３ｈꎬ离心(８０００ｒｍｉｎ－１ꎬ１０ｍｉｎ)收集沉淀并用蒸馏水－乙醇交替洗３次ꎬ冷冻干燥得到ＭＳＮ＠ＣＴＡＢ白色粉末ꎮ２.２㊀分析方法建立㊀２.２.１㊀色谱条件㊀ＤＴＸ色谱条件:色谱柱:Ｋｒｏｍａｓｉｌ(Ｃ１８ꎬ４.６ｍｍˑ１５０ｍｍꎬ５μｍ)ꎻ流动相:甲醇:乙腈:水(３５ʒ４０ʒ２５ꎬＶ/Ｖ/Ｖ)ꎻ检测波长:２３０ｎｍꎻ柱温:２５ħꎻ流速:１ｍＬｍｉｎ－１ꎻ进样量:２０μＬꎮＴＨＰ色谱条件:色谱柱:Ｋｒｏｍａｓｉｌ(Ｃ１８ꎬ４.６ｍｍˑ１５０ｍｍꎬ５μｍ)ꎻ流动相:乙腈:０.１ｍｏｌＬ－１醋酸铵溶液醋酸调至ｐＨ＝４(３５ʒ６５ꎬＶ/Ｖ)ꎻ检测波长:２５４ｎｍꎻ柱温:２５ħꎻ流速:０.８ｍＬｍｉｎ－１ꎻ进样量:２０μＬꎮ２.２.２㊀专属性试验㊀按２.２.１项下ＤＴＸ和ＴＨＰ的色谱条件ꎬ分别进样ＤＴＸ和ＴＨＰ对照品溶液㊁未载药纳米粒(ＦＡ－ＰＤＡ－ＭＳＮｓ)超声上清溶液及载药纳米粒(ＦＡ－ＰＤＡ－ＴＨＰ－ＤＴＸ－ＭＳＮｓ)超声上清溶液ꎬ检测方法的专属性ꎮ检测结果如下图所示ꎬＤＴＸ和ＴＨＰ的出峰时间分别为５.５１４ｍｉｎ和７.２１８ｍｉｎꎬ峰形良好ꎬ且载体材料对ＤＴＸ和ＴＨＰ的色谱峰均无影响ꎮ两药专属性分别见图１~２ꎮＡ.ＤＴＸ标准品ꎻＢ.ＭＳＮｓꎻＣ.ＴＨＰ－ＤＴＸ－ＭＳＮｓ图１㊀ＤＴＸ专属性考察Ａ.ＴＨＰ标准品ꎻＢ.ＦＡ－ＰＤＡ－ＭＳＮｓꎻＣ.ＦＡ－ＰＤＡ－ＴＨＰ－ＤＴＸ－ＭＳＮｓ图２㊀ＴＨＰ专属性考察２.２.３㊀标准曲线的绘制㊀精密配制浓度为２.００㊁１０.００㊁２０.００㊁５０.００㊁８０.００㊁１００.００μｇｍＬ－１的ＤＴＸ标准溶液ꎮ按２.２.１项下的色谱条件进行测定ꎬ以峰面积(Ａｓ)为纵坐标ꎬ以ＤＴＸ浓度(Ｃ)横坐标进行回归分析ꎬ得标准曲线方程为:Ａｓ＝１０６７９.３３３５Ｃ－１８３８９.５６４１(Ｒ２＝０.９９９０)ꎬ结果表明ꎬＤＴＸ在２.００~１００.００μｇｍＬ－１范围内线性关系良好ꎮ精密配制浓度为１.７８㊁４.４４㊁８.８８㊁２２.２０㊁３５.５２㊁４４.４０μｇｍＬ－１的ＴＨＰ标准溶液ꎮ按２.２.１项下的色谱条件进行测定ꎬ以峰面积(Ａｓ)为纵坐标ꎬ以浓度(Ｃ)为横坐标进行回归分析ꎬ得标准曲线方程为:Ａｓ＝４８２１７.８６２７Ｃ－６９６３０.３３１８(Ｒ２＝０.９９９０)ꎮ结果表明ꎬＴＨＰ在１.７８~４４.４０μｇｍＬ－１范围内线性关系良好ꎮ２.２.４㊀精密度考察㊀分别取低㊁中㊁高(１０.００㊁５０.００㊁１００.００μｇｍＬ－１)浓度的ＤＴＸ供试品溶液与低㊁中㊁高(４.４４㊁２２.２０㊁４４.４０μｇｍＬ－１)浓度的ＴＨＰ供试品溶液ꎬ按２.２.１项下条件ꎬ每种样品分别进样６次ꎬ连续测定３ｄꎬ测定并记录峰面积ꎬ计算ＤＴＸ与ＴＨＰ日内精密度及日间精密度ꎬ结ＲＳＤ均小于２.００％ꎬ此方法的日内㊁日间精密度良好ꎬ符合含量测定的要求ꎮ２.２.５㊀加样回收率的测定㊀取１.０ｍｇｍＬ－１ＭＳＮｓ乙醇溶液１ｍＬ分别与低㊁中㊁高(１０.００㊁５０.００㊁１００.００μｇｍＬ－１)浓度的ＤＴＸ供试品溶液或低㊁中㊁高(４.４４㊁２２.２０㊁４４.４０μｇｍＬ－１)浓度的ＴＨＰ供试品溶液以１ʒ１体积比进行混合ꎮ按照２.２.１项下的色谱条件进行测定计算其药物含量ꎮ回收率计算公式为:回收率＝(测定量－样品量)/加入量ˑ１００％ꎮ结果可知ꎬ两药加样回收率均满足«中国药典»２０２０年版对于含量测定的要求ꎮ２.３㊀药物的负载以及包封率与载药量检测方法的建立㊀称取定量ＭＳＮｓ置于１０ｍＬ的载药溶剂中ꎬ超声至分散均匀ꎬ加入定量ＴＨＰ和ＤＴＸ溶解ꎬ避光室温搅拌数小时实现两药同时负载ꎮ利用超声溶解法对ＦＡ－ＰＤＡ－ＴＨＰ－ＤＴＸ－ＭＳＮｓ载药量和包封率进行测定ꎮ即精密称量少量ＦＡ－ＰＤＡ－ＴＨＰ－ＤＴＸ－ＭＳＮｓ放置于无水乙醇(１ｍＬ)中ꎬ超声３０ｍｉｎꎬ８０００ｒｍｉｎ－１离心５ｍｉｎꎬ得上清ꎬ沉淀继续加入无水乙醇(１ｍＬ)超声ꎬ重复３次ꎮ合并上清ꎬ以２.２.１项下液相条件对两种药物进行含量测定ꎬ计算载药量㊁包封率ꎬ结果见表１ꎮＤＬ(％)＝Ｗ载/Ｗ总ˑ１００％ＥＥ(％)＝Ｗ载/Ｗ投ˑ１００％其中ＤＬ为载药量ꎬＥＥ为包封率ꎬＷ总为载药载体的质量ꎬＷ载为载药载体中药物的质量ꎬＷ投为投药量ꎮ表１㊀ＦＡ－ＰＤＡ－ＴＨＰ－ＤＴＸ－ＭＳＮｓ载药量包封率测定结果(ｎ＝３)ＥＥ(％)ＤＬ(％)ＤＴＸ３６.０２ʃ０.６８５.７２ʃ０.２５ＴＨＰ３６.９２ʃ０.４４１１.７７ʃ０.３３㊀㊀结果显示ꎬ利用超声溶解法测定ＦＡ－ＰＤＡ－ＴＨＰ－ＤＴＸ－ＭＳＮｓ中ＤＴＸ和ＴＨＰ的包封率㊁载药量准确度较高ꎬ重现性较好ꎬ可利用此法对纳米给药系统的包封率和载药量进行测定ꎮ２.４㊀制备工艺优化㊀２.４.１㊀药物载体比例的选择㊀为了优化两药的负载条件ꎬ本部分对药物载体比以及载药时间分别进行了单因素考察ꎮ固定载药时间为１２ｈꎬ改变药物载体比ꎬ两药包封率和载药量结果显示随着ＭＳＮｓ载体的比例减小ꎬ两种药物的包封率均减小ꎮ当药物载体比在１ʒ１~２ʒ１之间时ꎬ载药量仅有少量增加ꎮ造成这一现象的原因可能是由于当药物载体比达到１ʒ１时ꎬＭＳＮｓ孔道内药物几乎达到饱和ꎮ因此选择药物载体比为１ʒ１ꎮ２.４.２㊀载药时间的选择㊀固定负载溶剂为２５％乙醇溶液ꎬ药物载体比为１ʒ１ꎬ改变载药时间ꎬ两药包封率和载药量结果如表３ꎮ结果显示载药时间在６~１２ｈ时ꎬ随着搅拌时间的增加ꎬ两种药物的载药量和包封率均显著增加ꎬ当载药时间在１２~１８ｈ时ꎬ两种药物的总载药量仅有少量增加ꎬ这与在考察药物载体比中所提到的ＭＳＮｓ孔道所能负载药物达到饱和原因一致ꎮ两种药物随着搅拌时间的增加ꎬ两种药物的进入ＭＳＮｓ孔道的比例时有所变化ꎬ这一现象产生的原因是由于两种药的结构性质不同对于ＭＳＮｓ的吸附能力有所不同ꎬ因此存在一定的竞争关系ꎮ为了保证两种药物的最佳比例ꎬ选择搅拌时间为１２ｈ作为载药时间ꎮ表２㊀药物载体比对两药包封率及载药量的影响(ｎ＝３)药物载体比ＴＨＰＤＴＸＥＥ(％)ＤＬ(％)ＥＥ(％)ＤＬ(％)１ʒ２５０.２６ʃ０.８４１３.４１ʃ０.１９４８.９８ʃ０.１１６.５３ʃ０.０２１ʒ１３７.８３ʃ０.５３１８.３５ʃ０.２５３６.６６ʃ０.４８８.８９ʃ０.１３２ʒ１１９.５１ʃ０.２７１８.５１ʃ０.１９１９.６３ʃ０.２６９.４１ʃ０.１０表３㊀载药时间对两药包封率及载药量的影响(ｎ＝３)载药时间/ｈＴＨＰＤＴＸＥＥ(％)ＤＬ(％)ＥＥ(％)ＤＬ(％)６３１.７９ʃ０.６０１６.２５ʃ０.２４２７.５８ʃ０.４５７.０５ʃ０.０９１２３７.８３ʃ０.５３１８.３５ʃ０.２５３６.６６ʃ０.４８８.８９ʃ０.１３１８３９.１０ʃ０.７８１８.６０ʃ０.２７４２.２１ʃ０.７１１０.０４ʃ０.１１２.４.３㊀聚多巴胺膜的包覆及条件优化㊀聚多巴胺膜包覆基本操作如下:称取定量１０.００ｍｇＴＨＰ－ＤＴＸ－ＭＳＮｓ置于１０ｍＬ１０ｍｍｏｌＬ－１的Ｔｒｉｓ－ＨＣｌ溶液中(ｐＨ＝８.５)超声分散均匀ꎬ后向其中加入定量盐酸多巴胺ꎬ室温搅拌数小时ꎬ８０００ｒｍｉｎ－１１５ｍｉｎ离心得聚多巴胺膜包覆的载药介孔二氧化硅纳米粒(ＰＤＡ－ＴＨＰ－ＤＴＸ－ＭＳＮｓ)[１６]ꎮ首先固定包覆时间为３ｈꎬ向１０ｍｍｏｌＬ－１的Ｔｒｉｓ－ＨＣｌ(ｐＨ＝８.５)溶液加入盐酸多巴胺ꎬ使盐酸多巴胺终浓度分别为０.２５㊁０.５０㊁０.７５㊁１.００㊁１.２５ｍｇｍＬ－１ꎮ反应结束后离心得ＰＤＡ－ＴＨＰ－ＤＴＸ－ＭＳＮｓ并使用激光粒度仪测定粒径ꎮ图３㊀盐酸多巴胺浓度对于聚多巴胺膜包覆ＭＳＮｓ粒径的影响(ｎ＝３)㊀㊀图３结果表明ꎬ在盐酸多巴胺浓度为１.０ｍｇｍＬ－１时系统ＰＤＩ增加到０.６５７左右ꎬ表明测定溶液体系中粒径大小分布十分不均匀ꎬ造成这种现象可能是由于溶液中盐酸多巴胺浓度过大ꎬ部分盐酸多巴胺自身氧化成球状纳米粒ꎬ而这种纳米粒与ＰＤＡ－ＴＨＰ－ＤＴＸ－ＭＳＮｓ的粒径相差较为悬殊ꎬ最终使得体系内的ＰＤＩ分散系数增加ꎮ另外为尽可能实现ＰＤＡ对于ＭＳＮｓ孔道内药物的封堵作用ꎬ选择盐酸多巴胺浓度为０.５０ｍｇｍＬ－１作为包覆浓度ꎬ此时纳米粒子的粒径约为１８３.５ｎｍꎬ既可实现对于孔道内药物的封堵又满足纳米粒子被动靶向的粒径要求ꎮ在确定盐酸多巴胺浓度的基础上ꎬ分别搅拌２㊁３㊁４ｈꎮ反应结束后离心得ＰＤＡ－ＴＨＰ－ＤＴＸ－ＭＳＮｓꎮ取少量利用去离子水超声分散均匀ꎬ激光粒度仪测定粒径ꎮ图４㊀搅拌时间对于聚多巴胺膜包覆介孔二氧化硅粒径的影响(ｎ＝３)㊀㊀结果显示ꎬ随着搅拌时间的增加ꎬ纳米粒子的粒径逐渐增加ꎬＰＤＩ分散系数在固定盐酸多巴胺浓度的条件下ꎬ无明显变化ꎮ为同时满足封堵及被动靶向作用ꎬ故选择搅拌时间为３ｈꎬ此时粒径约为１８６.５ｎｍꎮ２.５㊀叶酸的偶联㊀称取１.０ｍｇＰＤＡ－ＴＨＰ－ＤＴＸ－ＭＳＮｓ超声分散于２００μＬ浓度为２０ｍｇｍＬ－１的聚乙烯亚胺(ＰＥＩ)溶液中ꎬ搅拌２ｈꎬ得到ＰＥＩ功能化的纳米颗粒ꎮ随后将４ｍＬ浓度为１ｍｇｍＬ－１的１－(３－二甲氨基丙基)－３－乙基碳二亚胺盐酸盐(ＥＤＣＨＣｌ)和１０ｍＬ浓度为１ｍｇｍＬ－１的Ｎ－羟基丁二酰亚胺(ＮＨＳ)溶液加入１ｍＬＦＡ溶液(１ｍｇｍＬ－１二甲基亚砜中)ꎬ反应３０ｍｉｎꎬ以活化ＦＡ的羧基ꎮ将该溶液快速加入ＰＥＩ功能化的ＰＤＡ－ＴＨＰ－ＤＴＸ－ＭＳＮｓ溶液中搅拌１２ｈꎬ最后在８０００ｒｍｉｎ－１离心１０ｍｉｎꎬ水和乙醇洗涤ꎬ收集ＦＡ偶联的ＰＤＡ－ＴＨＰ－ＤＴＸ－ＭＳＮｓ纳米粒子(ＦＡ－ＰＤＡ－ＴＨＰ－ＤＴＸ－ＭＳＮｓ)ꎬ３０ħ条件下ꎬ鼓风干燥ꎬ最终得ＦＡ－ＰＤＡ－ＴＨＰ－ＤＴＸ－ＭＳＮｓ干燥粉末ꎮ２.６㊀ＦＡ－ＰＤＡ－ＴＨＰ－ＤＴＸ－ＭＳＮｓ纳米粒的表征㊀２.６.１㊀纳米粒的粒径与电位㊀由ＰＤＡ－ＴＨＰ－ＤＴＸ－ＭＳＮｓ透射电镜图(见图５)可知ꎬＰＤＡ－ＴＨＰ－ＤＴＸ－ＭＳＮｓ的粒径在ＭＳＮｓ的基础上有所增加ꎬ在ＭＳＮｓ的外层有明显的黑色薄膜形成ꎮ图６显示ＭＳＮｓ㊁ＰＤＡ－ＴＨＰ－ＤＴＸ－ＭＳＮｓ与ＦＡ－ＰＤＡ－ＴＨＰ－ＤＴＸ－ＭＳＮｓ３种纳米粒粒径依次增加ꎬＰＤＩ指数均小于０.３ꎬ具有良好的分散性ꎮＡ.ＭＳＮｓꎻＢ.ＰＤＡ－ＴＨＰ－ＤＴＸ－ＭＳＮｓ图５㊀ＭＳＮｓ和ＰＤＡ－ＴＨＰ－ＤＴＸ－ＭＳＮｓ透射电镜图对比图７显示ＰＤＡ－ＴＨＰ－ＤＴＸ－ＭＳＮｓ因ＰＤＡ表面羟基的存在[１７]其Ｚｅｔａ电位在ＭＳＮｓ的基础上进一步降低为(－２４.７７ʃ１.１５)ｍＶꎬ由于ＰＥＩ胺基的质子化ꎬ使得ＰＥＩ－ＰＤＡ－ＴＨＰ－ＤＴＸ－ＭＳＮｓ电位反转(＋３８.０３ʃ０.５４)ｍＶꎬ最后活化后ＦＡ的羧基与ＰＥＩ的胺基通过酰胺反应进行连接ꎮ由于ＦＡ共轭作用以及对ＰＥＩ胺基的质子化覆盖作用ꎬ使得ＦＡ－ＰＤＡ－ＴＨＰ－ＤＴＸ－ＭＳＮｓ的Ｚｅｔａ电位略微下降至(＋２３.３ʃ０.６７)ｍＶ[１８]ꎮ２.６.２㊀Ｎ２吸附－解吸附分析㊀Ｎ２吸附－解吸附分析试验结果如图８~９所示ꎬＰＤＡ－ＭＳＮｓ及ＭＳＮｓ两者的物理吸附－脱附等温线均为典型的ＩＶ型脱附曲线ꎮ通过ＢＥＴ法和ＢＪＨ法对ＰＤＡ－ＭＳＮｓ的平均比表面积㊁孔容和孔径进行计算分析ꎬ(比表面积为３２５.７９５５ｍ２ｇ－１ꎻ孔容积为０.５２０９ｃｍ３ｇ－１ꎻ孔径为３.１１ｎｍ)结果表明孔径大小没有变化ꎬ但是比表面积和孔容积均明显减小ꎬ由此可得ＰＤＡ可实现对于ＭＳＮｓ的封堵作用ꎮ２.６.３㊀傅立叶红外变换光谱(ＦＴＩＲ)㊀ＭＳＮｓ㊁ＰＤＡ－ＭＳＮｓ㊁ＦＡ－ＰＤＡ－ＭＳＮｓ以及ＦＡ的傅立叶红外光扫描图谱如图１０所示ꎬ１０８７ｃｍ－１处为Ｓｉ－Ｏ－Ｓｉ反对称伸缩振动吸收峰ꎬ在９６６ｃｍ－１处为Ｓｉ－ＯＨ的弯曲振动吸收特征峰ꎮ８０８ｃｍ－１为Ｓｉ－Ｏ键的对称伸缩振动吸收峰ꎬ其上均为ＭＳＮｓ的特征红外峰ꎮ除ＦＡ单体外ꎬ其他样品的红外特征图谱均在ＭＳＮｓ特征图谱上增加其特征峰ꎬ３８１４㊁１５４１㊁１２３８ｃｍ－１等作为ＰＤＡ苯环上的特征峰ꎬ在ＭＳＮｓ原有吸收的基础上有一定程度的叠加ꎬ而在未共有波长处则由于ＰＤＡ对ＭＳＮｓ进行了覆盖ꎬＭＳＮｓ特征吸收有所减弱ꎮ１６２２ｃｍ－１和１６０８ｃｍ－１分别作为酰胺键的特征峰以及ＦＡ的红外特征图谱ꎬ均可作为ＦＡ成功偶联的判断依据[１９－２０]ꎮＡ.ＭＳＮｓꎻＢ.ＰＤＡ－ＴＨＰ－ＤＴＸ－ＭＳＮｓꎻＣ.ＦＡ－ＰＤＡ－ＴＨＰ－ＤＴＸ－ＭＳＮｓ图６㊀粒径分布图(ｎ＝３)图７㊀ＭＳＮｓ㊁ＰＤＡ－ＴＨＰ－ＤＴＸ－ＭＳＮｓ㊁ＰＥＩ功能化ＰＤＡ－ＴＨＰ－ＤＴＸ－ＭＳＮｓ㊁ＦＡ－ＰＤＡ－ＴＨＰ－ＤＴＸ－ＭＳＮｓＺｅｔａ电位(ｎ＝３)图８㊀ＭＳＮｓ㊁ＰＤＡ－ＭＳＮｓ氮气吸附－解吸附等温图２.６.４㊀热重分析(ＴＧ)㊀图１１为热重分析图ꎬ图中由上至下分别表示ＭＳＮｓ㊁ＰＤＡ－ＭＳＮｓ和ＦＡ－ＰＤＡ－ＭＳＮｓ的热重曲线ꎬ结果显示当检测温度从室温升至８００ħ时ꎬ三者的失重百分率分别为８.５９２１％㊁２１.０６３４％以及２８.８０２１％ꎮＭＳＮｓ在２００ħ以下重量的损失主要是由于高温脱去其表面吸附的水ꎻ２００ħ至８００ħ之间主要是由于是制备过程中模板剂ＣＴＡＢ未图９㊀ＭＳＮｓ㊁ＰＤＡ－ＭＳＮｓ孔径分布图图１０㊀ＭＳＮｓ㊁ＰＤＡ－ＭＳＮｓ㊁ＦＡ－ＰＤＡ－ＭＳＮｓ以及叶酸的傅立叶红外扫描图谱被彻底煅烧所造成的[２１]ꎮ扣除模板剂和吸附水的失重后ꎬＰＤＡ－ＭＳＮｓ㊁ＦＡ－ＰＤＡ－ＭＳＮｓ在２００ħ至８００ħ之间的失重率分别为１２.４７１３％和２０.２１００％ꎮ因此ꎬ该纳米给药系统中按照优化后的条件ＰＤＡ和ＦＡ靶向基团的接枝率分别为１２.４７１３％和７.４６８７％ꎮ２.７㊀体外释药方法与结果２.７.１㊀体外释药试验结果㊀将透析袋中装入２ｍＬ图１１㊀ＭＳＮｓ㊁ＰＤＡ－ＭＳＮｓ㊁ＦＡ－ＰＤＡ－ＭＳＮｓ热重分析曲线ＦＡ－ＰＤＡ－ＴＨＰ－ＤＴＸ－ＭＳＮｓ１％Ｔｗｅｅｎ－８０ＰＢＳ以及相同剂量的ＴＨＰ－ＤＴＸ游离溶液(各透析袋中ＴＨＰ㊁ＤＴＸ含量尽量保持一致)分别放置于条件为ｐＨ５.０㊁ｐＨ７.４㊁ｐＨ５.０＋ＮＩＲ㊁ｐＨ７.４＋ＮＩＲ的环境中(ｎ＝３)ꎮ在释药开始后ꎬ分别于０.２５㊁０.５㊁１㊁２㊁３㊁４㊁６㊁８㊁１０㊁１２㊁２４㊁４８㊁７２㊁９６ｈ量取１ｍＬ释药介质同时补加等量同温空白介质(激光照射组照射条件为２Ｗｃｍ－２ꎬ照射５ｍｉｎ后ꎬ后续同以上操作)ꎬ计算药物的累积释放率Ｑ(％)ꎮ不同条件下ＤＴＸ及ＴＨＰ累计释放百分率以及体外释放曲线见图１２~１３ꎮ各时间点药物累积释放百分率(Ｑ)的计算公式为:Ｑ(％)＝(Ｖ０Ｃｔ＋Ｖ ðｔ－１ｎ＝１Ｃｔ) １００％Ｗ－１式中Ｃｔ为在各时间点测得释放介质中的药物浓度(ｍｇｍＬ－１)ꎬＷ为投入药物的总重量(ｍｇ)ꎬＶ０为释放介质的总体积ꎬＶ为每次取样的体积ꎮ图１２㊀ＤＴＸ和纳米粒在各条件下的体外释放曲线(ｎ＝３)㊀㊀两药的累计释放曲线如图１２~１３所示ꎬ游离组在０~６ｈ快速释放ꎬ累计释放率可达到８５％左右ꎬ且不随ｐＨ值的变化而发生变化ꎮ而ＦＡ－ＰＤＡ－ＴＨＰ－ＤＴＸ－ＭＳＮｓ中的ＤＴＸ及ＴＨＰ的释放相较于游离药物能够显著延长体外释放时间ꎬ并且均表现图１３㊀ＴＨＰ和纳米粒在各条件下的体外释放曲线(ｎ＝３)出明显的ｐＨ响应ꎮ药物在９６ｈ的累计释放结果显示ꎬＦＡ－ＰＤＡ－ＴＨＰ－ＤＴＸ－ＭＳＮｓ在ｐＨ＝５.０的酸性环境下释放量可达至６３.７２％ʃ１.６６％ꎬｐＨ＝７.４的中性环境下仅为１６.５７％ʃ０.５１％ꎮ这是由于在酸性条件下ＰＤＡ会部分分解ꎬ有利于药物的释放ꎮ除此之外ꎬ分别在６㊁１２㊁２４㊁４８㊁７２ｈ时间点利用２Ｗｃｍ－２的ＮＩＲ辐照５ｍｉｎꎬ结果显示两种药物在ＮＩＲ照射的条件下其释放量均有一定程度的提高ꎬ且在酸性条件下ꎬ提高幅度更大约达２０％ꎮ由此可见在酸性环境和近红外激光的条件下可加快靶向纳米给药系统内药物的释放ꎬ减少化疗药物非特异性释放ꎮ２.７.２㊀方程拟合㊀依据上述两药在不同条件下各时间点下的累计释放百分率ꎬ对ＦＡ－ＰＤＡ－ＴＨＰ－ＤＴＸ－ＭＳＮｓ的体外释放曲线进行方程拟合ꎬ以进一步阐明ＦＡ－ＰＤＡ－ＴＨＰ－ＤＴＸ－ＭＳＮｓ的释药机制ꎮ㊀㊀体外释放曲线方程拟合结果显示(见表４~５)ꎬ两种药物无论是在ｐＨ为７.４还是５.０ꎬ以及是否有ＮＩＲ照射的条件下ꎬ其释药曲线均与Ｗｅｉｂｕｌｌ释药模型的拟合度最高ꎬ该模型可较好的适用于速释和缓释药物的释放拟合ꎮ为进一步研究其释放机理ꎬ将不同条件下的药物释放曲线与Ｒｉｔｇｅｒ－Ｐｅｐｐａｓ方程Ｑ＝Ｋｔｍ(Ｋ㊁ｍ为常数)拟合ꎮ当ｍɤ０.４５时ꎬ其药物释放机制为Ｆｉｃｋ扩散ꎻ当０.４５<ｍ<０.８９时ꎬ其药物释放机制为ｎｏｎ－Ｆｉｃｋ扩散ꎬ即药物扩散和骨架溶蚀的共同作用ꎻ当ｍȡ０.８９时ꎬ其药物释放机制为骨架溶蚀[２２]ꎮ由上表可知两药在ｐＨ为７.４时ꎬ对于Ｒｉｔ￣ｇｅｒ－Ｐｅｐｐａｓ方程拟合中ꎬ其特征ｍ值均小于０.４５ꎬ释药机制为简单的Ｆｉｃｋ扩散ꎬ而ｐＨ为５.０时ꎬ两药释放曲线对于Ｒｉｔｇｅｒ－Ｐｅｐｐａｓ方程拟合中ꎬ其特征ｍ值介于０.４５到０.８９之间ꎬ释药机制符合药物扩散和骨架溶蚀的共同作用ꎮ这也呼应了纳米粒子表面的ＰＤＡ薄膜在酸性条件下能够裂解的理论ꎮ表４㊀ＤＴＸ累积释药曲线的拟合方程模型条件拟合方程Ｒ２一级动力学ｐＨ＝７.４ＤＴＸ＋ＮＩＲＱ＝２０.２０５１(１－ｅ－０.０７７４ｔ)０.９２０６ｐＨ＝５.０ＤＴＸＱ＝９７.３７７１(１－ｅ－０.０１２５ｔ)０.９８７５ｐＨ＝５.０ＤＴＸ＋ＮＩＲＱ＝１２９.２２２４(１－ｅ－００.０１２２ｔ)０.９８９３ＨｉｇｕｃｈｉｐＨ＝７.４ＤＴＸＱ＝１.７５９８ｔ１/２＋２.６６３２０.９７０５ｐＨ＝７.４ＤＴＸ＋ＮＩＲＱ＝２.２１１３ｔ１/２＋２.９９０５０.９５８１ｐＨ＝５.０ＤＴＸＱ＝７.２１３１ｔ１/２－６.３５８３０.９５４０ｐＨ＝５.０ＤＴＸ＋ＮＩＲＱ＝９.８６１４ｔ１/２－１１.６１１７０.９５３６ＷｅｉｂｕｌｌｐＨ＝７.４ＤＴＸＱ＝５８.８３２３(１－ｅ－(０.０００７(ｔ－０.１３２１))０.３５８９)０.９９８２ｐＨ＝７.４ＤＴＸ＋ＮＩＲＱ＝２８.５６０５(１－ｅ－(０.０２４３(ｔ＋０.０２８５))０.５０８１)０.９９３３ｐＨ＝５.０ＤＴＸＱ＝６７.９８８７(１－ｅ－(０.０１７２(ｔ＋１３.８７７４))２.０２３０)０.９９８２表５㊀ＴＨＰ累积释药曲线的拟合方程模型条件拟合方程２一级动力学ｐＨ＝７.４ＴＨＰ＋ＮＩＲＱ＝２２.８２０９(１－ｅ－０.０３１９ｔ)０.９３５９ｐＨ＝５.０ＴＨＰＱ＝９５.０３３９(１－ｅ－０.０１２３ｔ)０.９８３４ｐＨ＝５.０ＴＨＰ＋ＮＩＲＱ＝１１７.４１５４(１－ｅ－０.０１５４ｔ)０.９８７１ＨｉｇｕｃｈｉｐＨ＝７.４ＴＨＰＱ＝１.５８０４ｔ１/２＋１.７２６８０.９９２６ｐＨ＝７.４ＴＨＰ＋ＮＩＲＱ＝２.３３９３ｔ１/２＋０.２８９６０.９８８３ｐＨ＝５.０ＴＨＰＱ＝７.０７４０１/２－６.９８１８０.９４３７ｐＨ＝５.０ＴＨＰ＋ＮＩＲＱ＝１０.３９４５ｔ１/２－１２.４２２４０.９５８４ＷｅｉｂｕｌｌｐＨ＝７.４ＴＨＰＱ＝２０.４９６７(１－ｅ－(０.０２１１(ｔ＋２.０３２０))０.６６１５)０.９９９２ｐＨ＝７.４ＴＨＰ＋ＮＩＲＱ＝３１２.４６１１(１－ｅ－(０.０００１(ｔ＋１.５２４３))０.５７４２)０.９９３０ｐＨ＝５.０ＴＨＰＱ＝６２.８６９６(１－ｅ－(０.０１８１(ｔ＋１４.７５８９))２.３３８０)０.９９７１３㊀结论本试验中以ＭＳＮｓ作为纳米药物载体ꎬＤＴＸ和ＴＨＰ作为模型药物ꎬ负载于ＭＳＮｓ孔道及表面ꎬ利用盐酸多巴胺在碱性条件下氧化形成ＰＤＡ薄膜包覆于ＭＳＮｓ表面ꎬ最后利用酰胺反应将ＦＡ靶头修饰于ＰＤＡ薄膜的表面成功制备得ＦＡ－ＰＤＡ－ＴＨＰ－ＤＴＸ－ＭＳＮｓ纳米粒ꎮ对ＦＡ－ＰＤＡ－ＴＨＰ－ＤＴＸ－ＭＳＮｓ纳米粒的制备工艺进行优化ꎬ考察了优化后纳米粒的表征以及释药行为ꎬ证实了靶向纳米粒的成功制备并能实现刺激性响应释药ꎮ综上所述ꎬ本研究从药剂学的角度为实现化疗与光疗相结合的靶向治疗方法提供了新的策略和依据ꎮ基于光热效应的聚多巴胺膜靶向纳米粒作为一种新型的可实现光热治疗与化疗相结合的纳米粒ꎬ展现出良好的应用前景ꎬ可为日后实现光热治疗和化疗联用提供一定的参考ꎮ但与此同时ꎬ新的递送系统在临床应用方面还存在着各方面的困难ꎬ具体例如其表面正电荷极易与血液中的组分发生聚集而导致生物毒性增强和生物利用度降低ꎬ可使用如透明质酸或中药多糖进行逆转电荷ꎮ因此在后续实验中ꎬＦＡ－ＰＤＡ－ＴＨＰ－ＤＴＸ－ＭＳＮｓ纳米递送系统可进行生物安全性以及体内外药效学实验ꎬ对其进行进一步优化ꎮ参考文献:[１]㊀张静.线粒体靶向的光－化疗纳米粒用于增强乳腺癌的免疫治疗研究[Ｄ].济南:山东大学ꎬ２０２０. [２]ＬＩＵＹꎬＢＨＡＴＴＡＲＡＩＰꎬＤＡＩＺꎬｅｔａｌ.Ｐｈｏｔｏｔｈｅｒｍａｌｔｈｅｒａｐｙａｎｄｐｈｏｔｏａｃｏｕｓｔｉｃｉｍａｇｉｎｇｖｉａｎａｎｏｔｈｅｒａｎｏｓｔｉｃｓｉｎｆｉｇｈｔｉｎｇｃａｎｃｅｒ[Ｊ].ＣｈｅｍＳｏｃＲｅｖꎬ２０１９ꎬ４８(７):２０５３－２１０８.[３]ＫＨＡＦＡＪＩＭꎬＺＡＭＡＮＩＭꎬＧＯＬＩＺＡＤＥＨＭꎬｅｔａｌ.Ｉｎｏｒｇａｎｉｃｎａｎｏｍａｔｅｒｉａｌｓｆｏｒｃｈｅｍｏ/ｐｈｏｔｏｔｈｅｒｍａｌｔｈｅｒａｐｙ:ａｐｒｏｍｉｓｉｎｇｈｏｒｉｚｏｎｏｎｅｆｆｅｃｔｉｖｅｃａｎｃｅｒｔｒｅａｔｍｅｎｔ[Ｊ].Ｂｉｏ￣ｐｈｙｓＲｅｖꎬ２０１９ꎬ１１(３):３３５－３５２.[４]ＨＡＳＳＡＮＭＳꎬＡＮＳＡＲＩＪꎬＳＰＯＯＮＥＲＤꎬｅｔａｌ.Ｃｈｅｍｏｔｈｅｒ￣ａｐｙｆｏｒｂｒｅａｓｔｃａｎｃｅｒ(Ｒｅｖｉｅｗ)[Ｊ].ＯｎｃｏｌＲｅｐꎬ２０１０ꎬ２４(５):１１２１－１１３１.[５]崔鹏辉ꎬ李俏ꎬ曲云鹏ꎬ等.乳腺癌化疗相关心脏毒性的防治研究进展[Ｊ].中国心血管病研究ꎬ２０２１ꎬ１９(１０):９５６－９６０.[６]张强ꎬ李恒平ꎬ王俊ꎬ等.ＤＴＸ影响胃癌细胞增殖㊁迁移和侵袭的作用机制[Ｊ].中国老年学杂志ꎬ２０２１ꎬ４１(１５):３３４４－３３４９.[７]ＭＡＲＵＰＵＤＩＮＩꎬＨＡＮＪＥꎬＬＩＫＷꎬｅｔａｌ.Ｐａｃｌｉｔａｘｅｌ:ａＲｅｖｉｅｗｏｆＡｄｖｅｒｓｅＴｏｘｉｃｉｔｉｅｓａｎｄＮｏｖｅｌＤｅｌｉｖｅｒｙＳｔｒａｔｅｇｉｅｓ[Ｊ].ＥｘｐｅｒｔＯｐｉｎＤｒｕｇＳａｆꎬ２００７ꎬ６(５):６０９－６２１.[８]王海刚ꎬ刘向红.多功能介孔二氧化硅纳米粒在肿瘤治疗中的研究进展[Ｊ].中国医院药学杂志ꎬ２０１９ꎬ３９(１０):１０９９－１１０４.[９]ＣＨＥＮＨꎬＣＨＥＮＨꎬＷＡＮＧＹꎬｅｔａｌ.ＡＮｏｖｅｌＳｅｌｆ－ＣｏａｔｅｄＰｏｌｙｄｏｐａｍｉｎｅＮａｎｏｐａｒｔｉｃｌｅｆｏｒＳｙｎｅｒｇｉｓｔｉｃＰｈｏｔｏｔｈｅｒｍａｌ－Ｃｈｅｍｏｔｈｅｒａｐｙ[Ｊ].ＣｏｌｌｏｉｄｓＳｕｒｆＢＢｉｏｉｎｔｅｒｆａｃｅｓꎬ２０２１ꎬ２００(６):１１１５９６.[１０]顾冰冰.高性能有机纳米光学治疗试剂设计及其抗肿瘤研究[Ｄ].南京:南京邮电大学ꎬ２０２０.[１１]ＺＨＵＨꎬＣＨＥＮＧＰꎬＣＨＥＮＰꎬｅｔａｌ.ＲｅｃｅｎｔＰｒｏｇｒｅｓｓｉｎＴｈｅＤｅｖｅｌｏｐｍｅｎｔｏｆＮｅａｒ－ＩｎｆｒａｒｅｄＯｒｇａｎｉｃＰｈｏｔｏｔｈｅｒｍａｌａｎｄＰｈｏｔｏｄｙｎａｍｉｃＮａｎｏｔｈｅｒａｐｅｕｔｉｃｓ[Ｊ].ＢｉｏｍａｔｅｒＳｃｉꎬ２０１８ꎬ６(４):７４６－７６５.[１２]张文君ꎬ吴梦婷ꎬ吕春艳ꎬ等.介孔二氧化硅在药物递送系统及其体内外研究进展[Ｊ].生物技术通报ꎬ２０１９ꎬ３５(１２):１５９－１６８.[１３]ＬＯＷＰＳꎬＨＥＮＮＥＷＡꎬＤＯＯＲＮＥＷＥＥＲＤＤＤ.ＤｉｓｃｏｖｅｒｙａｎｄＤｅｖｅｌｏｐｍｅｎｔｏｆＦｏｌｉｃ－Ａｃｉｄ－ＢａｓｅｄＲｅｃｅｐｔｏｒＴａｒｇｅｔｉｎｇｆｏｒＩｍａｇｉｎｇａｎｄＴｈｅｒａｐｙｏｆＣａｎｃｅｒａｎｄＩｎｆｌａｍｍａｔｏｒｙＤｉｓｅａｓｅｓ[Ｊ].ＡｃｃＣｈｅｍＲｅｓ.２００８ꎬ４１(１):１２０－１２９.[１４]ＮＡＲＭＡＮＩＡꎬＲＥＺＶＡＮＩＭꎬＦＡＲＨＯＯＤＢꎬｅｔａｌ.ＦｏｌｉｃＡｃｉｄＦｕｎｃｔｉｏｎａｌｉｚｅｄＮａｎｏｐａｒｔｉｃｌｅｓＡｓＰｈａｒｍａｃｅｕｔｉｃａｌＣａｒｒｉｅｒｓｉｎＤｒｕｇＤｅｌｉｖｅｒｙＳｙｓｔｅｍｓ[Ｊ].ＤｒｕｇＤｅｖＲｅｓꎬ２０１９ꎬ８０(４):４０４－４２４.[１５]孙玉林.左旋棉酚介孔硅纳米粒子制备及其体外研究[Ｄ].西安:西安电子科技大学ꎬ２０１４.[１６]张梦营.基于多巴胺自聚合法和化学合成法构建紫杉醇靶向纳米粒的抗肿瘤对比研究[Ｄ].北京:北京协和医学院ꎬ２０２０.[１７]ＳＨＡＯＭꎬＣＨＡＮＧＣꎬＬＩＵＺꎬｅｔａｌ.ＰｏｌｙｄｏｐａｍｉｎｅＣｏａｔｅｄＨｏｌｌｏｗＭｅｓｏｐｏｒｏｕｓＳｉｌｉｃａＮａｎｏｐａｒｔｉｃｌｅｓａｓＰｈ－ＳｅｎｓｉｔｉｖｅＮａｎｏｃａｒｒｉｅｒｓｆｏｒＯｖｅｒｃｏｍｉｎｇＭｕｌｔｉｄｒｕｇＲｅｓｉｓｔａｎｃｅ[Ｊ].ＣｏｌｌｏｉｄｓＳｕｒｆＢＢｉｏｉｎｔｅｒｆａｃｅｓꎬ２０１９(１８３):１１０４２７. [１８]ＬＩＨꎬＪＩＮＺꎬＣＨＯＳꎬｅｔａｌ.Ｆｏｌａｔｅ－Ｒｅｃｅｐｔｏｒ－ＴａｒｇｅｔｅｄＮｉｒ－ＳｅｎｓｉｔｉｖｅＰｏｌｙｄｏｐａｍｉｎｅＮａｎｏｐａｒｔｉｃｌｅｓｆｏｒＣｈｅｍｏ－Ｐｈｏｔｏ￣ｔｈｅｒｍａｌＣａｎｃｅｒＴｈｅｒａｐｙ[Ｊ].Ｎａｎｏｔｅｃｈｎｏｌｏｇｙꎬ２０１７ꎬ２８(４２):４２５１０１.[１９]资鹏鹏.载盐酸二甲双胍中空介孔二氧化硅纳米粒的制备及性能研究[Ｄ].南昌:江西师范大学ꎬ２０２１. [２０]ＬＩＨꎬＪＩＮＺꎬＣＨＯＳꎬｅｔａｌ.Ｆｏｌａｔｅ－Ｒｅｃｅｐｔｏｒ－ＴａｒｇｅｔｅｄＮｉｒ－ＳｅｎｓｉｔｉｖｅＰｏｌｙｄｏｐａｍｉｎｅＮａｎｏｐａｒｔｉｃｌｅｓｆｏｒＣｈｅｍｏ－Ｐｈｏｔｏ￣ｔｈｅｒｍａｌＣａｎｃｅｒＴｈｅｒａｐｙ[Ｊ].Ｎａｎｏｔｅｃｈｎｏｌｏｇｙꎬ２０１７ꎬ２８(４２):４２５１０１.[２１]盛晓丹ꎬ刘臻ꎬ罗砚曦ꎬ等.聚多巴胺修饰的载榄香烯介孔二氧化硅纳米粒的制备及其靶向抗肿瘤活性研究[Ｊ].中草药ꎬ２０２０ꎬ５１(１０):２７４５－２７５４.[２２]王帅.ｐＨ敏感性共载药脂质－介孔二氧化硅复合纳米载体的构建与体外性能[Ｄ].深圳:深圳大学ꎬ２０１９.(收稿日期:２０２２－１０－１８)。

Materials Characterization

Materials Characterization Materials characterization is a crucial aspect of materials science and engineering, as it involves the study of the structure, properties, andperformance of materials. This field plays a significant role in variousindustries, including manufacturing, construction, and healthcare. In this response, we will explore the importance of materials characterization, thevarious techniques used in the process, and the impact of advancements in thisfield on society. First and foremost, materials characterization is essential for understanding the behavior of materials under different conditions. By analyzingthe structure and properties of materials, scientists and engineers can make informed decisions about the suitability of a material for a specific application. For example, in the aerospace industry, materials characterization is used toensure that the materials used in aircraft components can withstand extreme temperatures and pressures. Without this knowledge, the safety and reliability of such critical components would be compromised. Moreover, materialscharacterization is crucial for quality control and product development. By characterizing the properties of materials, manufacturers can ensure that their products meet the required standards and specifications. This is particularly important in industries such as automotive and electronics, where the performance and reliability of materials directly impact the quality of the final product. For instance, in the semiconductor industry, materials characterization is used to assess the purity and crystalline structure of silicon wafers, which are essential for the production of microchips. In addition to its industrial applications, materials characterization also plays a significant role in scientific researchand innovation. By gaining a deeper understanding of the structure-property relationships of materials, researchers can develop new materials with enhanced properties and performance. This has led to the development of advanced materials such as carbon nanotubes, graphene, and high-strength alloys, which have revolutionized various industries and paved the way for technological advancements. The process of materials characterization involves a wide range of techniques,each offering unique insights into the properties of materials. These techniques include microscopy, spectroscopy, diffraction, thermal analysis, and mechanicaltesting, among others. For example, scanning electron microscopy (SEM) allows scientists to visualize the microstructure of materials at high magnification, while X-ray diffraction (XRD) can be used to determine the crystal structure of a material. By combining these techniques, researchers can obtain a comprehensive understanding of the composition, structure, and behavior of materials. Furthermore, advancements in materials characterization have the potential to address global challenges and improve the quality of life. For instance, in the field of healthcare, materials characterization is used to develop biocompatible materials for medical implants, drug delivery systems, and tissue engineering. By understanding the interactions between materials and biological systems, researchers can design materials that promote healing and minimize the risk of rejection or infection. This has the potential to significantly improve the success rates of medical procedures and enhance patient outcomes. In conclusion, materials characterization is a fundamental aspect of materials science and engineering, with far-reaching implications for various industries and scientific research. By gaining a deeper understanding of the structure and properties of materials, scientists and engineers can develop new materials, improve existing ones, and ensure the safety and reliability of products. As advancements in this field continue to drive innovation, the impact of materials characterization on society is expected to grow, leading to new opportunities and solutions to global challenges.。

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a rXiv:h ep-e x /31134v114Nov23Characterization of the Response of Superheated Droplet (Bubble)Detectors M.Barnab´e -Heider,M.Di Marco,P.Doane,M-H.Genest,R.Gornea,C.Leroy ‡,L.Lessard,J.P.Martin,U.Wichoski,V.Zacek Groupe de Physique des Particules,D´e partement de Physique,Universit´e de Montr´e al,C.P.6128,Succ.Centre-Ville,Montr´e al (Qu´e bec)H3C 3J7,Canada A.J.Noble Department of Physics,Queens University Kingston (Ontario)K7L 3NG,Canada E.Behnke,J.Behnke,W.Feighery,I.Levine,C.Mathusi,J.Neurenberg,R.Nymberg Department of Physics and Astronomy,Indiana University South Bend South Bend,Indiana,46634,USA S.N.Shore Dipartimento di Fisica ”Enrico Fermi”,Universtit`a di Pisa,Pisa,I-56127,Italia R.Noulty,S.Kanagalingam Bubbles Technology Industries,Chalk River (Ontario)K0J 1J0,CanadaPICASSO COLLABORATION1.IntroductionSuperheated droplet detectors,here referred to as”bubble detectors”,use superheated liquid droplets(active medium)dispersed and suspended in a polymerized gel[1],[2]. Presently,these droplet detectors consist of an emulsion of metastable superheated droplets of liquids(such as C3F8,C4F10,CF3Br,CCl2F2)at a temperature higher than their boiling point,dispersed in an aqueous solution,subsequently polymerized after dissolution of an appropriate concentration of a heavy salt(e.g.,CsCl)in water to equalize densities of droplets and solution.By applying an adequate pressure,the boiling temperature can be raised allowing the emulsion to be kept in a liquid state. Under this external pressure,the detectors are insensitive to radiation.By removing the external pressure,the liquid becomes superheated and sensitive to radiation.Bubble formation occurs through liquid-to-vapour phase transitions, triggered by the energy deposited by radiation.This can be the result of nuclear recoils (through interactions with neutrons or other particles),or through direct deposition (gamma,beta,alpha particles).Bubble detectors are threshold detectors as they need to achieve a minimal energy deposition to induce a phase transition.Their sensitivity to various types of radiation strongly depends on the operating temperature and pressure. The liquid-to-vapour transition is explosive in nature and is accompanied by an acoustic shock wave which can be detected with piezoelectric sensors.The signal measurement of the detectors is described in[3]These detectors are re-usable by re-compressing the bubbles back to droplets.Bubble detectors of small volume,typically10m l,representing0.1-0.2g of active material have been used for many years in applications such as portable neutron dosimeters for personal dosimetry or the measurement of the radiationﬁelds near particle accelerators or reactors.Over the last several years,Bubble Technology Industries(BTI)and the University of Montreal have been collaborating in the making of bubble detectors using detector formulations that are more appropriate for the application of the Picasso group.To distinguish these detectors from the conventional commercial bubble detectors,we have named these detectors”Special Bubble Detectors(SBD)”.More recently,the PICASSO group has developed detectors of larger volume of the type shown in Fig.(1) with the aim to perform a direct measurement of neutralinos predicted by minimal supersymmetric models of cold dark matter(CDM)particles.The very low interaction cross section between CDM and the nuclei of the detector’s active medium requires the use of very massive detectors to achieve a sensitivity level allowing the detection of CDM particles in the galactic environment[4].2.The SBD’s and their operationThe response of the SBD’s to incoming particles or radiation is determined by thermodynamic properties of the active gas,such as operating temperature and pressure.The detector operation can be understood in the framework of the theory of Seitz[5]which describes bubble formation as being triggered by the heat spike produced by the energy deposited when a particle traverses a depth of superheated medium.The boiling temperature,T b,increases with pressure.The superheated condition is achieved when the temperature of the liquid phase is higher than its boiling temperature.Active liquids at room temperature,but subjected to high enough pressures,are not superheated.However,if the pressure is lowered to atmospheric value,the liquids become superheated in the absence of heterogeneous nucleation.In SBD’s,over the temperature range from boiling to critical temperatures(deﬁned as theFigure 1.A large-volume droplet detector module (1-litre volume)equipped withpiezoelectric sensors glued on the surface for signal detection.The container can bepressurized up to 10bars.Typical C x F y gas loading presently achieved for this typeof detector is in the 5-10g/litre range.temperature at which the surface tension becomes zero),there is a pressure thresholdabove which the droplets will be thermodynamically stable and the detector will notbe sensitive.If the pressure is released or considerably decreased,droplets becomesuperheated and the detector becomes sensitive.The droplet should normally make a transition from the liquid (high potentialenergy)to the gaseous phase (lower potential energy).However,undisturbed,thedroplet is in a metastable state since it must overcome a potential barrier to make thetransition from the liquid to the gas phase.This can be done if the droplet receivesan extra amount of energy such as the heat due to the energy deposited by incomingparticles.The potential barrier is given by Gibbs’equationE c =16π(p i−p 0)2,(1)where p 0and p i ,the externally applied pressure and the vapour pressure in the bubble,respectively,are temperature dependent.The diﬀerence between these two pressuresrepresents the degree of superheat.The surface tension of the liquid-vapour interfaceat temperature T is given by σ(T )=σ0(T c−T )/(T c−T 0)where T c is the criticaltemperature of the gas,σ0is the surface tension at a reference temperature T 0,usuallythe boiling temperature T b .For a combination of two gases,T b and T c can be adjusted,depending on the mixture ratio.For instance T b =-19.2o C,T c =92.6o C for a SBD-100detector,(loaded with a mixture of ﬂuorocarbons);whereas T b =1.7o C,T c =113.0o C for SBD-1000detectors (loaded with 100%C 4F 10)[7].The response of varioustypes of SBD’s can be compared by using the reduced superheat variable,s,deﬁnedas s =(T −T b )/(T c −T b ).Bubble formation will occur when a minimum deposited energy,E Rth ,exceeds thethreshold value E c within a distance l c =a R c ,where the critical radius R c is givenby:R c =2σ(T )energy of the nuclei recoiling after their collision with the incident particle),the energydeposited along l c is E dep=dE/dx×l c.The condition to trigger a liquid-to-vapourtransition is E dep≥E Rth.Since it is not the total deposited energy that will trigger a liquid-to-vapour transition,but the fraction of this energy transformed into heat,the actual minimum or threshold energy,E Rth,for recoil detection is related to E c byan eﬃciency factor,η=E c/E Rth(2<η<6%)[1,10].The threshold value beingdependent on the operating temperature and pressure,the detector can be set into aregime where it responds mainly to nuclear recoils and discrimination can be achievedagainst background radiations from minimum ionizing particles and gamma rays. 3.Alpha-particle response measurement and simulationThe heavy salt and other ingredients,mixed in the gel at the present stage of detectorproduction,contains contaminants which areα-emitters,such as U/Th and daughters.Theαbackground is one of the main backgrounds at normal temperatures of SBDoperation since other backgrounds contribute to the detector signal predominantly athigher temperatures.(Neutrons,discussed in the next section,will be greatly shieldedagainst by operating the detectors deep underground).Therefore,the response of SBDtoα-particles has to be investigated carefully.The alpha response was studied using a1l SBD-1000fabricated at BTI(BubbleTechnology Industry).In the fabrication process,27.8m l of an americium solution(AmCl3in0,5M HCl)of known activity(0,7215Bq/m l)were added to the gel solutionto create a detector spiked with20Bqs of241Am.Then,the detector liquid wasadded,followed by mixing and polymerisation ing this detector,thealpha detection eﬃciency was measured at temperatures ranging from6o C to50o C(see Fig.(2)).The alpha eﬃciency is deﬁned asǫ=τA similar alpha measurement has been done with a SBD-100,but the threshold temperature could not be reached.The higher operating temperature of the SBD-1000 allows us to explore the threshold region for theﬁrst time.Note that the SBD-1000 and SBD-100detectors have the same response curve when the reduced superheat is used to describe the temperature dependence(see Fig.(3)).Figure3.Detector response(count rate)of the1l SBD-1000and SBD-100,spiked with20Bqs of241Am,as a function of reduced superheat.The alpha response was simulated,using Geant4.5.2[11].The geometry of the virtual detectors was approximated to an8m l cylinder(theﬁrst generation of detectors were built in vials)made out of polycarbonate andﬁlled with a gel loaded with CsCl. This approximation was valid even for the1l detector.The correction of the response due to a diﬀerent surface to volume ratio was calculated to be negligible due to the very short range of the alpha particles.The density of the superheated droplets was varied as a function of temperature and the droplets were dispersed randomly in the gel.For all simulations the experimentally known distribution of droplet diameters was used[7].The loading was assumed to be0.7%,a choice validated by a comparison between the neutron eﬃciency of the simulated detector and another1l detector for which the droplet distribution and loading were directly measured.Alpha particles were generated randomly in the gel,with an energy spectrum corresponding to the 241Am decay.The tracking of each particle or nucleus was done step by step and when any track entered a droplet,the outputﬁle was updated by adding a code identifying the particle or nucleus involved,the energy it deposited and the corresponding deposition length. The ionization of low energy nuclei was taken into account,using the ICRUis the energy that the recoiling nucleus can deposit within one critical diameter(2R c), a length smaller than the range of the recoiling nucleus considered.Therefore,this method of calculation assumes that the energy deposition necessary is less than the recoiling energy of the nucleus.To maintain the coherence between neutron and alpha measurements,the simulations strongly suggest that all the recoiling energy is needed. The critical length for the necessary energy to be deposited will hence be greater than the range of the nucleus considered.The probability,P(E dep,E Rth),that a recoil nucleus at an energy near threshold will generate an explosive droplet-bubble transition is described by[7]P=1−exp −b(E dep−E Rth)N for a larger number of events.One can do further tests to check these assumptions by simulating the neutron response to see if the result is consistent with the alpha case,using the same energy deposition and critical length requirements.4.Neutron response measurement and simulationSBD’s have a high eﬃciency for detecting neutrons while being insensitive to minimum ionizing particles and to nearly all sources of background when operated at the temperature and pressure region of interest for neutralino recoil detection[7].From purely kinematical considerations,nuclear recoil thresholds in SBD’s can be obtained in the same range for neutrons of low energy(e.g.,from10keV up to a few MeV)and massive neutralinos(60GeV/c2up to1TeV)with no sensitivity to minimum ionizing particles and gamma-radiation.Therefore,the SBD response to neutrons has to be studied carefully.The SBD response to mono-energetic neutrons has been measured as a function of the temperature.These mono-energetic neutrons are obtained from7Li(p,n)7Be reactions at the Tandem van der Graaﬀfacility of the Universit´e de Montr´e al.The detector response(count rate)to mono-energetic neutrons of200and400keV as a function of operating temperature are shown in Figs.(4)and(5),respectively,for a detector of8m l volume loaded with100%C4F10droplets.From such curves,one canextract the threshold temperature,T th ,for a given neutron energy by extrapolatingthe curves to the lowest point.Then,it is possible to represent the neutron thresholdenergy as a function of temperature(Fig.(6)).Figure 4.neutrons as a function ofsimulated response gives aloading of Figure 5.neutrons as a function ofsimulated response gives aloading of The neutron beams wasalso as in the alpha case.Theloading was normalized by awas interpreted as theloading The energy variation in theproton to ﬂuctuate around thebeam in the simulation weregiven an keV for 200keV neutrons.Neutron all types of nuclei usingthe can be seen in Figs.(4)and (5),the simulated response ﬁts well the experimental data for E =200and 400keV,validating the critical length and minimal energy requirements used to ﬁt thealpha response.Fitting the neutron experimental data also allows the determinationFigure6.Neutron threshold energy(E Rth)as a function of temperature for various operating pressures[6].of the detector’s loading.The values of0.61±0.06%and0.69±0.03%obtained at200 and400keV respectively are consistent with each other.5.Expected Neutralino ResponseDue to its19F content,PICASSO’s detectors are especially suitable to search for spin-dependent neutralino interactions.19F is a spin-1Maxwellian velocity distribution.In the recoil signal temperature range(from20o C to 50o C),the main contribution to the background is due to the alpha particles resulting from U/Th contaminations in the detector itself.The contribution from neutrons will be low for installations deep underground and with adequate shielding.The sensitivity to minimum ionizing particles and gamma-rays is expected to occur above50o C.As can be seen in Fig.(7),the signal becomes clearly visible at a background contamination level of10−14g/g U/Th.The knowledge of the precise shape of the alpha response allows us to extract either the signal or an upper bound to the neutralino cross-section. Presently the contamination level in the detectors is at the level of approximately 10−10g/g.Work is in progress to reduce this contribution substantially in the near future.6.ConclusionsSimulations performed to understand the response of superheated droplet detectors to neutrons and alpha particles indicate that all the data can be well described with a unique,consistent set of variables which parameterize the underlying model of recoil energy threshold and energy deposition(Seitz theory).The simulations of the neutron data are able to trace the response of mono-energetic neutrons as a function of temperature over several orders of magnitude in count rate.The experimental alpha response is equally well described and the simulations show that it is the alpha particles which mainly trigger droplet formation by their speciﬁc energy loss along the track,rather than the recoiling237Np nucleus.The detection eﬃciency at higher temperatures is consistent with the assumption that the alpha emitters are distributed uniformly in the gel surrounding the droplets.Further tests and simulations with U and Th will be carried out soon.These cases are complicated by the fact that these chains need not be in secular equilibrium,and the radon daughters may diﬀuse through the detector.On the experimental side,we found a consistent description of the alpha response for a series of alpha spiked detectors with diﬀerent active detector liquids and therefore diﬀerent operating temperatures,if represented in terms of reduced superheat.The range of alpha sensitivity coincides with the range of temperatures where droplet detectors are sensitive for neutralino induced recoils,but the shape of the response curves are diﬀerent.The precise knowledge of the alpha response is therefore important in order to increase the sensitivity for neutralino detection in the presence of alpha emitting contaminants.In the meantime a new phase of the project has started with the production of larger scale1l modules and their installation and operation at the location of the SNO detector in the Creighton mine at Sudbury,Ontario.Ten detector modules have been installed so far and operated over a period of several months,with their data analysis being in progress.[1]R.E.Apfel,Nucl.Instr.Meth.162(1979),603.[2]H.Ing,R.A.Noulty and T.D.McLean,Radiation Measurements,Vol.27,No.1,(1997),pp.1-11.[3]R.Gornea,Syst`e me d’acquisition des donn´e es et de contrˆo le du d´e tecteur`agouttelettes surchauﬀ´e es dans le cadre du projet PICASSO,MSc.Thesis, University of Montreal,April2002.[4]N.Boukhira et al.,Suitability of superheated droplet detectors for dark mattersearch,Astroparticle Physics,Vol.14(2000)227.[5]Frederik Seitz,On the Theory of the Bubble Chambers,The Physics of Fluids,Vol.1,No.1,(1958),p.2.[6]M.Barnab´e-Heider et al.,Proceedings of the7th International Conference onAdvanced Technology and Particle Physics,October15-192001,Villa Olmo, Como,Italy,Editors M.Barone,E.Borchi,J.Huston,C.Leroy,P.G.Rancoita, P.L.Riboni,R.Ruchti,World Scientiﬁc,Singapore(2002),pp.85-95.[7]N.Boukhira,Etalonnage aux neutrons d’un d´e tecteur`a gouttelettes surchauﬀ´e espour la recherche de la mati`e re sombre,MSc.Thesis,University of Montreal, January2002.[8]R.E.Apfel,S.C.Roy and Y.C.Lo,Phys.Rev.A31(1985)3194.[9]C.R.Bell,N.P.Oberle,W.Rohsenow,N.Todreas and C.Tso,Nucl.Sci.Eng.,53(1974),pp.458-465.[10]M.J.Harper and J.C.Rich,Nucl.Instr.Meth.A336(1993),pp.220-225.[11]http://geant4.web.cern.ch/geant4/[12]ICRU(A.Allisy et al),Stopping Powers and Ranges for Protons and AlphaParticles,ICRU Report49,1993.[13]J.F.Ziegler and J.P.Biersack,TRIM(Transport of Ions in Matter),version TRIM-96in SRIM-2000(The Stopping and Range of Ions in Matter),version2000.39 coding by D.J.Mawrick et al.,c 1998,1999by IBM Co.[14]L.K.Pan and C.-K.C.Wang,Nucl.Instr.Meth.A420(1999),pp.345-355.[15]ENDF/B-VI:Cross Section Evaluation Working Group,ENDF/B-VI SummaryDocument,Report BNL-NCS-17541(ENDF-201)(1991),edited by P.F.Rose, National Nuclear Data Center,Brookhave National Laboratory,Upton,NY, USA.[16]J.Ellis,R.Flores,Phys.lett.B263(1991),259.。