Imprint of the Global Hubble Flow on Galactic Rotation Curves

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The Impact of Globalization

The Impact of GlobalizationGlobalization is a complex phenomenon that has transformed the world into a more interconnected and interdependent place. It has brought about both positive and negative impacts on various aspects of our lives, including the economy, culture, politics, and environment. In this essay, I will explore the impact of globalization from different perspectives and shed light on its advantages and disadvantages.From an economic perspective, globalization has brought about significant changes in the global economy. It has facilitated the growth of international trade and investment, which has led to increased economic growth and development in many countries. The rise of multinational corporations and the expansion of global supply chains have created new opportunities for businesses to reach new markets and access new sources of capital and expertise. This has led to increased competition, innovation, and productivity, which has benefited consumers and businesses alike.However, globalization has also created new challenges and risks for the global economy. The increasing integration of financial markets has made countries more vulnerable to financial crises and economic shocks. The growing power of multinational corporations has led to concerns about their impact on local economies and the environment. The rise of global inequality has also become a major concern, as the benefits of globalization have not been evenly distributed across different regions and social groups.From a cultural perspective, globalization has had a profound impact on the way we live and interact with each other. It has facilitated the spread of ideas, values, and cultural practices across borders, leading to greater cultural exchange and diversity. This has enabled people to learn from each other and appreciate different cultures, which has enriched our global community.However, globalization has also led to the homogenization of culture, as the dominance of Western culture has marginalized and eroded traditional cultures in many parts of the world. The spread of consumerism and materialism has also led to the commodification of culture, as cultural products and practices are increasingly marketedand sold as commodities. This has led to concerns about the loss of cultural diversity and the erosion of local identities.From a political perspective, globalization has had a profound impact on the way we govern ourselves and interact with other countries. It has facilitated the growth of international organizations and institutions, such as the United Nations, World Trade Organization, and International Monetary Fund, which have played a crucial role in promoting global cooperation and resolving conflicts.However, globalization has also led to new challenges and risks for the global political system. The increasing power of multinational corporations has led to concerns about their influence on government policies and decision-making. The rise of populist and nationalist movements in many countries has also challenged the idea of global cooperation and threatened the stability of the international system.From an environmental perspective, globalization has had a significant impact on the natural world. It has facilitated the growth of global trade and transportation, which has led to increased emissions of greenhouse gases and other pollutants. The expansion of global supply chains has also led to the depletion of natural resources and the destruction of ecosystems.However, globalization has also created new opportunities for environmental cooperation and sustainability. The rise of global environmental movements and the growing awareness of the need for sustainable development have led to new initiatives and policies aimed at reducing the negative impact of globalization on the environment.In conclusion, globalization has had a profound impact on various aspects of our lives, both positive and negative. While it has facilitated the growth of the global economy, promoted cultural exchange and diversity, enabled global cooperation and resolved conflicts, and created new opportunities for environmental cooperation and sustainability, it has also created new challenges and risks for the global system. As we continue to navigate the complexities of globalization, it is important to recognize its advantages and disadvantages and work towards a more equitable and sustainable global system.。

Exploring the Concept of Universal Basic Income

Exploring the Concept of Universal Basic Income Universal Basic Income (UBI) is a concept that has gained significant attention in recent years. The idea of providing a guaranteed income to all citizens regardless of their employment status has been debated by economists, politicians, and social activists. While UBI has its supporters, it also has its critics. In this essay, we will explore the concept of Universal Basic Income, its benefits, drawbacks, and the challenges that come with its implementation.Proponents of UBI argue that it is an effective way to combat poverty and income inequality. They argue that UBI would provide a safety net for the most vulnerable members of society, ensuring that everyone has access to basic necessities such as food, shelter, and healthcare. UBI would also provide individuals with the freedom to pursue their interests without the fear of financial insecurity. This could lead to increased creativity and innovation, as people would be able to take risks and explore new ideas without the fear of failure.Critics of UBI argue that it is an expensive and unsustainable policy. They argue that UBI would require a significant increase in taxes, which would discourage investment and hinder economic growth. Critics also argue that UBI would discourage people from working, leading to a decline in productivity and economic output. They argue that UBI would create a culture of dependency, where people rely on government handouts instead of working to support themselves.One of the biggest challenges of implementing UBI is determining the amount of money that should be provided to each individual. Some argue that the amount should be enough to cover basic necessities such as food, shelter, and healthcare. Others argue that it should be enough to provide a comfortable standard of living. Determining the amount of UBI is a complex issue that requires careful consideration of economic factors, social norms, and political realities.Another challenge of implementing UBI is determining how it would be funded. Some argue that UBI could be funded through a combination of taxes on the wealthy, reductionsin government spending, and the implementation of a value-added tax (VAT). Others argue that UBI would require a complete overhaul of the tax system, including the implementation of a wealth tax and the elimination of tax breaks for corporations.Despite the challenges, UBI has been successfully implemented in several countries. In Finland, a two-year UBI pilot program was launched in 2017, providing 2,000 unemployed individuals with a month ly payment of €560. The program was designed to test the effectiveness of UBI in reducing poverty and promoting employment. While the results of the program were mixed, it did provide valuable insights into the potential benefits and drawbacks of UBI.In conclusion, Universal Basic Income is a concept that has the potential to transform our society. While it has its supporters and critics, it is clear that UBI is a complex issue that requires careful consideration of economic, social, and political factors. The implementation of UBI would require significant changes to our tax system and government spending, as well as a willingness to experiment with new policies and ideas. Despite the challenges, UBI has the potential to provide a safety net for the most vulnerable members of society and promote economic growth and innovation.。

The impact of globalization on the economy

Globalization has had a significant impact on the global economy since its surge in the late 20th century. It has opened up new opportunities for trade, investment, and cultural exchange, but it has also brought challenges and disruptions to many economies.One of the most noticeable impacts of globalization on the economy is the increase in international trade. With the removal of trade barriers and the lowering of tariffs, businesses now have easier access to foreign markets. This has led to a surge in global trade, with an increasing number of companies sourcing and selling their products and services across borders. As a result, consumers have access to a wider variety of goods and services at lower prices, ultimately raising living standards and increasing overall welfare.Globalization has also led to an increase in foreign direct investment (FDI). Multinational corporations are now able to invest in different countries, allowing for the transfer of capital, technology, and know-how to less developed regions. This FDI has brought new job opportunities and economic growth to many countries, particularly in emerging markets. However, it also raises concerns about exploitation and the exacerbation of income inequality within and across countries.Furthermore, globalization has had a profound impact on the labor market. The trend of offshoring and outsourcing has led to the relocation of production and service jobs to countries with lower labor costs. This has led to the displacement of certain industries and workers in developed countries, resultingin job losses and wage stagnation. On the other hand, it has improved job opportunities and living standard for workers in developing countries.In addition, globalization has facilitated the spread of technology and innovation across countries. Companies gain access to the latest technologies from around the world and can quickly adopt and implement them in their operations. This has led to increased productivity and competitiveness in many industries, strengthening the global economy as a whole.However, the impact of globalization is not universally positive. It has also led to the increased interconnectedness of the global financial system, resulting in heightened vulnerability to financial crises. The 2008 global financial crisis, for example, spread rapidly across countries, causing severe economic downturns worldwide. In addition, the increased mobility of capital has made it easier for speculative investors to create financial instability through rapid capital flows in and out of emerging markets.Moreover, globalization has raised concerns over the environmental implications of increased production and trade. The rise in global transportation and the expansion of industrial production have contributed to higher energy consumption, greenhouse gas emissions, and environmental degradation.Finally, globalization has raised concerns about the erosion of national sovereignty. The harmonization of economic policies and regulations, as well as the rise of international trade agreements, has led to an increased transfer of authority from national governments to supranational bodies and multinationalcorporations.In conclusion, the impact of globalization on the global economy has been profound and multifaceted. While it has brought about new opportunities for growth and development, it has also created challenges and disruptions that must be carefully managed. As globalization continues to evolve, policymakers and businesses will need to address its impact on employment, inequality, the environment, and financial stability to ensure a more balanced and sustainable global economy.。

Principles of Plasma Discharges and Materials Processing9

CHAPTER8MOLECULAR COLLISIONS8.1INTRODUCTIONBasic concepts of gas-phase collisions were introduced in Chapter3,where we described only those processes needed to model the simplest noble gas discharges: electron–atom ionization,excitation,and elastic scattering;and ion–atom elastic scattering and resonant charge transfer.In this chapter we introduce other collisional processes that are central to the description of chemically reactive discharges.These include the dissociation of molecules,the generation and destruction of negative ions,and gas-phase chemical reactions.Whereas the cross sections have been measured reasonably well for the noble gases,with measurements in reasonable agreement with theory,this is not the case for collisions in molecular gases.Hundreds of potentially signiﬁcant collisional reactions must be examined in simple diatomic gas discharges such as oxygen.For feedstocks such as CF4/O2,SiH4/O2,etc.,the complexity can be overwhelming.Furthermore,even when the signiﬁcant processes have been identiﬁed,most of the cross sections have been neither measured nor calculated. Hence,one must often rely on estimates based on semiempirical or semiclassical methods,or on measurements made on molecules analogous to those of interest. As might be expected,data are most readily available for simple diatomic and polyatomic gases.Principles of Plasma Discharges and Materials Processing,by M.A.Lieberman and A.J.Lichtenberg. ISBN0-471-72001-1Copyright#2005John Wiley&Sons,Inc.235236MOLECULAR COLLISIONS8.2MOLECULAR STRUCTUREThe energy levels for the electronic states of a single atom were described in Chapter3.The energy levels of molecules are more complicated for two reasons. First,molecules have additional vibrational and rotational degrees of freedom due to the motions of their nuclei,with corresponding quantized energies E v and E J. Second,the energy E e of each electronic state depends on the instantaneous con-ﬁguration of the nuclei.For a diatomic molecule,E e depends on a single coordinate R,the spacing between the two nuclei.Since the nuclear motions are slow compared to the electronic motions,the electronic state can be determined for anyﬁxed spacing.We can therefore represent each quantized electronic level for a frozen set of nuclear positions as a graph of E e versus R,as shown in Figure8.1.For a mole-cule to be stable,the ground(minimum energy)electronic state must have a minimum at some value R1corresponding to the mean intermolecular separation (curve1).In this case,energy must be supplied in order to separate the atoms (R!1).An excited electronic state can either have a minimum( R2for curve2) or not(curve3).Note that R2and R1do not generally coincide.As for atoms, excited states may be short lived(unstable to electric dipole radiation)or may be metastable.Various electronic levels may tend to the same energy in the unbound (R!1)limit. Array FIGURE8.1.Potential energy curves for the electronic states of a diatomic molecule.For diatomic molecules,the electronic states are speciﬁedﬁrst by the component (in units of hÀ)L of the total orbital angular momentum along the internuclear axis, with the symbols S,P,D,and F corresponding to L¼0,+1,+2,and+3,in analogy with atomic nomenclature.All but the S states are doubly degenerate in L.For S states,þandÀsuperscripts are often used to denote whether the wave function is symmetric or antisymmetric with respect to reﬂection at any plane through the internuclear axis.The total electron spin angular momentum S (in units of hÀ)is also speciﬁed,with the multiplicity2Sþ1written as a preﬁxed superscript,as for atomic states.Finally,for homonuclear molecules(H2,N2,O2, etc.)the subscripts g or u are written to denote whether the wave function is sym-metric or antisymmetric with respect to interchange of the nuclei.In this notation, the ground states of H2and N2are both singlets,1Sþg,and that of O2is a triplet,3SÀg .For polyatomic molecules,the electronic energy levels depend on more thanone nuclear coordinate,so Figure8.1must be generalized.Furthermore,since there is generally no axis of symmetry,the states cannot be characterized by the quantum number L,and other naming conventions are used.Such states are often speciﬁed empirically through characterization of measured optical emission spectra.Typical spacings of low-lying electronic energy levels range from a few to tens of volts,as for atoms.Vibrational and Rotational MotionsUnfreezing the nuclear vibrational and rotational motions leads to additional quan-tized structure on smaller energy scales,as illustrated in Figure8.2.The simplest (harmonic oscillator)model for the vibration of diatomic molecules leads to equally spaced quantized,nondegenerate energy levelse E v¼hÀv vib vþ1 2(8:2:1)where v¼0,1,2,...is the vibrational quantum number and v vib is the linearized vibration frequency.Fitting a quadratic functione E v¼12k vib(RÀ R)2(8:2:2)near the minimum of a stable energy level curve such as those shown in Figure8.1, we can estimatev vib%k vibm Rmol1=2(8:2:3)where k vib is the“spring constant”and m Rmol is the reduced mass of the AB molecule.The spacing hÀv vib between vibrational energy levels for a low-lying8.2MOLECULAR STRUCTURE237stable electronic state is typically a few tenths of a volt.Hence for molecules in equi-librium at room temperature (0.026V),only the v ¼0level is signiﬁcantly popula-ted.However,collisional processes can excite strongly nonequilibrium vibrational energy levels.We indicate by the short horizontal line segments in Figure 8.1a few of the vibrational energy levels for the stable electronic states.The length of each segment gives the range of classically allowed vibrational motions.Note that even the ground state (v ¼0)has a ﬁnite width D R 1as shown,because from(8.2.1),the v ¼0state has a nonzero vibrational energy 1h Àv vib .The actual separ-ation D R about Rfor the ground state has a Gaussian distribution,and tends toward a distribution peaked at the classical turning points for the vibrational motion as v !1.The vibrational motion becomes anharmonic and the level spa-cings tend to zero as the unbound vibrational energy is approached (E v !D E 1).FIGURE 8.2.Vibrational and rotational levels of two electronic states A and B of a molecule;the three double arrows indicate examples of transitions in the pure rotation spectrum,the rotation–vibration spectrum,and the electronic spectrum (after Herzberg,1971).238MOLECULAR COLLISIONSFor E v.D E1,the vibrational states form a continuum,corresponding to unbound classical motion of the nuclei(breakup of the molecule).For a polyatomic molecule there are many degrees of freedom for vibrational motion,leading to a very compli-cated structure for the vibrational levels.The simplest(dumbbell)model for the rotation of diatomic molecules leads to the nonuniform quantized energy levelse E J¼hÀ22I molJ(Jþ1)(8:2:4)where I mol¼m Rmol R2is the moment of inertia and J¼0,1,2,...is the rotational quantum number.The levels are degenerate,with2Jþ1states for the J th level. The spacing between rotational levels increases with J(see Figure8.2).The spacing between the lowest(J¼0to J¼1)levels typically corresponds to an energy of0.001–0.01V;hence,many low-lying levels are populated in thermal equilibrium at room temperature.Optical EmissionAn excited molecular state can decay to a lower energy state by emission of a photon or by breakup of the molecule.As shown in Figure8.2,the radiation can be emitted by a transition between electronic levels,between vibrational levels of the same electronic state,or between rotational levels of the same electronic and vibrational state;the radiation typically lies within the optical,infrared,or microwave frequency range,respectively.Electric dipole radiation is the strongest mechanism for photon emission,having typical transition times of t rad 10À9s,as obtained in (3.4.13).The selection rules for electric dipole radiation areDL¼0,+1(8:2:5a)D S¼0(8:2:5b) In addition,for transitions between S states the only allowed transitions areSþÀ!Sþand SÀÀ!SÀ(8:2:6) and for homonuclear molecules,the only allowed transitions aregÀ!u and uÀ!g(8:2:7) Hence homonuclear diatomic molecules do not have a pure vibrational or rotational spectrum.Radiative transitions between electronic levels having many different vibrational and rotational initial andﬁnal states give rise to a structure of emission and absorption bands within which a set of closely spaced frequencies appear.These give rise to characteristic molecular emission and absorption bands when observed8.2MOLECULAR STRUCTURE239using low-resolution optical spectrometers.As for atoms,metastable molecular states having no electric dipole transitions to lower levels also exist.These have life-times much exceeding10À6s;they can give rise to weak optical band structures due to magnetic dipole or electric quadrupole radiation.Electric dipole radiation between vibrational levels of the same electronic state is permitted for molecules having permanent dipole moments.In the harmonic oscillator approximation,the selection rule is D v¼+1;weaker transitions D v¼+2,+3,...are permitted for anharmonic vibrational motion.The preceding description of molecular structure applies to molecules having arbi-trary electronic charge.This includes neutral molecules AB,positive molecular ions ABþ,AB2þ,etc.and negative molecular ions ABÀ.The potential energy curves for the various electronic states,regardless of molecular charge,are commonly plotted on the same diagram.Figures8.3and8.4give these for some important electronic statesof HÀ2,H2,and Hþ2,and of OÀ2,O2,and Oþ2,respectively.Examples of both attractive(having a potential energy minimum)and repulsive(having no minimum)states can be seen.The vibrational levels are labeled with the quantum number v for the attrac-tive levels.The ground states of both Hþ2and Oþ2are attractive;hence these molecular ions are stable against autodissociation(ABþ!AþBþor AþþB).Similarly,the ground states of H2and O2are attractive and lie below those of Hþ2and Oþ2;hence they are stable against autodissociation and autoionization(AB!ABþþe).For some molecules,for example,diatomic argon,the ABþion is stable but the AB neutral is not stable.For all molecules,the AB ground state lies below the ABþground state and is stable against autoionization.Excited states can be attractive or repulsive.A few of the attractive states may be metastable;some examples are the 3P u state of H2and the1D g,1Sþgand3D u states of O2.Negative IonsRecall from Section7.2that many neutral atoms have a positive electron afﬁnity E aff;that is,the reactionAþeÀ!AÀis exothermic with energy E aff(in volts).If E aff is negative,then AÀis unstable to autodetachment,AÀ!Aþe.A similar phenomenon is found for negative molecular ions.A stable ABÀion exists if its ground(lowest energy)state has a potential minimum that lies below the ground state of AB.This is generally true only for strongly electronegative gases having large electron afﬁnities,such as O2 (E aff%1:463V for O atoms)and the halogens(E aff.3V for the atoms).For example,Figure8.4shows that the2P g ground state of OÀ2is stable,with E aff% 0:43V for O2.For weakly electronegative or for electropositive gases,the minimum of the ground state of ABÀgenerally lies above the ground state of AB,and ABÀis unstable to autodetachment.An example is hydrogen,which is weakly electronegative(E aff%0:754V for H atoms).Figure8.3shows that the2Sþu ground state of HÀ2is unstable,although the HÀion itself is stable.In an elec-tropositive gas such as N2(E aff.0),both NÀ2and NÀare unstable. 240MOLECULAR COLLISIONS8.3ELECTRON COLLISIONS WITH MOLECULESThe interaction time for the collision of a typical (1–10V)electron with a molecule is short,t c 2a 0=v e 10À16–10À15s,compared to the typical time for a molecule to vibrate,t vib 10À14–10À13s.Hence for electron collisional excitation of a mole-cule to an excited electronic state,the new vibrational (and rotational)state canbeFIGURE 8.3.Potential energy curves for H À2,H 2,and H þ2.(From Jeffery I.Steinfeld,Molecules and Radiation:An Introduction to Modern Molecular Spectroscopy ,2d ed.#MIT Press,1985.)8.3ELECTRON COLLISIONS WITH MOLECULES 241FIGURE 8.4.Potential energy curves for O À2,O 2,and O þ2.(From Jeffery I.Steinfeld,Molecules and Radiation:An Introduction to Modern Molecular Spectroscopy ,2d ed.#MIT Press,1985.)242MOLECULAR COLLISIONS8.3ELECTRON COLLISIONS WITH MOLECULES243 determined by freezing the nuclear motions during the collision.This is known as the Franck–Condon principle and is illustrated in Figure8.1by the vertical line a,showing the collisional excitation atﬁxed R to a high quantum number bound vibrational state and by the vertical line b,showing excitation atﬁxed R to a vibra-tionally unbound state,in which breakup of the molecule is energetically permitted. Since the typical transition time for electric dipole radiation(t rad 10À9–10À8s)is long compared to the dissociation( vibrational)time t diss,excitation to an excited state will generally lead to dissociation when it is energetically permitted.Finally, we note that the time between collisions t c)t rad in typical low-pressure processing discharges.Summarizing the ordering of timescales for electron–molecule collisions,we havet at t c(t vib t diss(t rad(t cDissociationElectron impact dissociation,eþABÀ!AþBþeof feedstock gases plays a central role in the chemistry of low-pressure reactive discharges.The variety of possible dissociation processes is illustrated in Figure8.5.In collisions a or a0,the v¼0ground state of AB is excited to a repulsive state of AB.The required threshold energy E thr is E a for collision a and E a0for Array FIGURE8.5.Illustrating the variety of dissociation processes for electron collisions with molecules.collision a0,and it leads to an energy after dissociation lying between E aÀE diss and E a0ÀE diss that is shared among the dissociation products(here,A and B). Typically,E aÀE diss few volts;consequently,hot neutral fragments are typically generated by dissociation processes.If these hot fragments hit the substrate surface, they can profoundly affect the process chemistry.In collision b,the ground state AB is excited to an attractive state of AB at an energy E b that exceeds the binding energy E diss of the AB molecule,resulting in dissociation of AB with frag-ment energy E bÀE diss.In collision b0,the excitation energy E b0¼E diss,and the fragments have low energies;hence this process creates fragments having energies ranging from essentially thermal energies up to E bÀE diss few volts.In collision c,the AB atom is excited to the bound excited state ABÃ(labeled5),which sub-sequently radiates to the unbound AB state(labeled3),which then dissociates.The threshold energy required is large,and the fragments are hot.Collision c can also lead to dissociation of an excited state by a radiationless transfer from state5to state4near the point where the two states cross:ABÃðboundÞÀ!ABÃðunboundÞÀ!AþBÃThe fragments can be both hot and in excited states.We discuss such radiationless electronic transitions in the next section.This phenomenon is known as predisso-ciation.Finally,a collision(not labeled in theﬁgure)to state4can lead to dis-sociation of ABÃ,again resulting in hot excited fragments.The process of electron impact excitation of a molecule is similar to that of an atom,and,consequently,the cross sections have a similar form.A simple classical estimate of the dissociation cross section for a level having excitation energy U1can be found by requiring that an incident electron having energy W transfer an energy W L lying between U1and U2to a valence electron.Here,U2is the energy of the next higher level.Then integrating the differential cross section d s[given in(3.4.20)and repeated here],d s¼pe24021Wd W LW2L(3:4:20)over W L,we obtains diss¼0W,U1pe24pe021W1U1À1WU1,W,U2pe24021W1U1À1U2W.U28>>>>>><>>>>>>:(8:3:1)244MOLECULAR COLLISIONSLetting U2ÀU1(U1and introducing voltage units W¼e E,U1¼e E1and U2¼e E2,we haves diss¼0E,E1s0EÀE11E1,E,E2s0E2ÀE1EE.E28>>>><>>>>:(8:3:2)wheres0¼pe4pe0E12(8:3:3)We see that the dissociation cross section rises linearly from the threshold energy E thr%E1to a maximum value s0(E2ÀE1)=E thr at E2and then falls off as1=E. Actually,E1and E2can depend on the nuclear separation R.In this case,(8.3.2) should be averaged over the range of R s corresponding to the ground-state vibrational energy,leading to a broadened dependence of the average cross section on energy E.The maximum cross section is typically of order10À15cm2. Typical rate constants for a single dissociation process with E thr&T e have an Arrhenius formK diss/K diss0expÀE thr T e(8:3:4)where K diss0 10À7cm3=s.However,in some cases E thr.T e.For excitation to an attractive state,an appropriate average over the fraction of the ground-state vibration that leads to dissociation must be taken.Dissociative IonizationIn addition to normal ionization,eþABÀ!ABþþ2eelectron–molecule collisions can lead to dissociative ionizationeþABÀ!AþBþþ2eThese processes,common for polyatomic molecules,are illustrated in Figure8.6.In collision a having threshold energy E iz,the molecular ion ABþis formed.Collisionsb andc occur at higher threshold energies E diz and result in dissociative ionization,8.3ELECTRON COLLISIONS WITH MOLECULES245leading to the formation of fast,positively charged ions and neutrals.These cross sections have a similar form to the Thompson ionization cross section for atoms.Dissociative RecombinationThe electron collision,e þAB þÀ!A þB Ãillustrated as d and d 0in Figure 8.6,destroys an electron–ion pair and leads to the production of fast excited neutral fragments.Since the electron is captured,it is not available to carry away a part of the reaction energy.Consequently,the collision cross section has a resonant character,falling to very low values for E ,E d and E .E d 0.However,a large number of excited states A Ãand B Ãhaving increasing principal quantum numbers n and energies can be among the reaction products.Consequently,the rate constants can be large,of order 10À7–10À6cm 3=s.Dissocia-tive recombination to the ground states of A and B cannot occur because the potential energy curve for AB þis always greater than the potential energycurveFIGURE 8.6.Illustration of dissociative ionization and dissociative recombination for electron collisions with molecules.246MOLECULAR COLLISIONSfor the repulsive state of AB.Two-body recombination for atomic ions or for mol-ecular ions that do not subsequently dissociate can only occur with emission of a photon:eþAþÀ!Aþh n:As shown in Section9.2,the rate constants are typically three toﬁve orders of magnitude lower than for dissociative recombination.Example of HydrogenThe example of H2illustrates some of the inelastic electron collision phenomena we have discussed.In order of increasing electron impact energy,at a threshold energy of 8:8V,there is excitation to the repulsive3Sþu state followed by dissociation into two fast H fragments carrying 2:2V/atom.At11.5V,the1Sþu bound state is excited,with subsequent electric dipole radiation in the ultraviolet region to the1Sþg ground state.At11.8V,there is excitation to the3Sþg bound state,followedby electric dipole radiation to the3Sþu repulsive state,followed by dissociation with 2:2V/atom.At12.6V,the1P u bound state is excited,with UV emission tothe ground state.At15.4V,the2Sþg ground state of Hþ2is excited,leading to the pro-duction of Hþ2ions.At28V,excitation of the repulsive2Sþu state of Hþ2leads to thedissociative ionization of H2,with 5V each for the H and Hþfragments.Dissociative Electron AttachmentThe processes,eþABÀ!AþBÀproduce negative ion fragments as well as neutrals.They are important in discharges containing atoms having positive electron afﬁnities,not only because of the pro-duction of negative ions,but because the threshold energy for production of negative ion fragments is usually lower than for pure dissociation processes.A variety of pro-cesses are possible,as shown in Figure8.7.Since the impacting electron is captured and is not available to carry excess collision energy away,dissociative attachment is a resonant process that is important only within a narrow energy range.The maximum cross sections are generally much smaller than the hard-sphere cross section of the molecule.Attachment generally proceeds by collisional excitation from the ground AB state to a repulsive ABÀstate,which subsequently either auto-detaches or dissociates.The attachment cross section is determined by the balance between these processes.For most molecules,the dissociation energy E diss of AB is greater than the electron afﬁnity E affB of B,leading to the potential energy curves shown in Figure8.7a.In this case,the cross section is large only for impact energies lying between a minimum value E thr,for collision a,and a maximum value E0thr for8.3ELECTRON COLLISIONS WITH MOLECULES247FIGURE 8.7.Illustration of a variety of electron attachment processes for electron collisions with molecules:(a )capture into a repulsive state;(b )capture into an attractive state;(c )capture of slow electrons into a repulsive state;(d )polar dissociation.248MOLECULAR COLLISIONScollision a 0.The fragments are hot,having energies lying between minimum and maximum values E min ¼E thr þE affB ÀE diss and E max ¼E 0thr þE af fB ÀE diss .Since the AB Àstate lies above the AB state for R ,R x ,autodetachment can occur as the mol-ecules begin to separate:AB À!AB þe.Hence the cross section for production of negative ions can be much smaller than that for excitation of the AB Àrepulsive state.As a crude estimate,for the same energy,the autodetachment rate is ﬃﬃﬃﬃﬃﬃﬃﬃﬃﬃﬃﬃﬃM R =m p 100times the dissociation rate of the repulsive AB Àmolecule,where M R is the reduced mass.Hence only one out of 100excitations lead to dissociative attachment.Excitation to the AB Àbound state can also lead to dissociative attachment,as shown in Figure 8.7b .Here the cross section is signiﬁcant only for E thr ,E ,E 0thr ,but the fragments can have low energies,with a minimum energy of zero and a maximum energy of E 0thr þE affB ÀE diss .Collision b,e þAB À!AB ÀÃdoes not lead to production of AB Àions because energy and momentum are not gen-erally conserved when two bodies collide elastically to form one body (see Problem3.12).Hence the excited AB ÀÃion separates,AB ÀÃÀ!e þABunless vibrational radiation or collision with a third body carries off the excess energy.These processes are both slow in low-pressure discharges (see Section 9.2).At high pressures (say,atmospheric),three-body attachment to form AB Àcan be very important.For a few molecules,such as some halogens,the electron afﬁnity of the atom exceeds the dissociation energy of the neutral molecule,leading to the potential energy curves shown in Figure 8.7c .In this case the range of electron impact ener-gies E for excitation of the AB Àrepulsive state includes E ¼0.Consequently,there is no threshold energy,and very slow electrons can produce dissociative attachment,resulting in hot neutral and negative ion fragments.The range of R s over which auto-detachment can occur is small;hence the maximum cross sections for dissociative attachment can be as high as 10À16cm 2.A simple classical estimate of electron capture can be made using the differential scattering cross section for energy loss (3.4.20),in a manner similar to that done for dissociation.For electron capture to an energy level E 1that is unstable to autode-tachment,and with the additional constraint for capture that the incident electron energy lie within E 1and E 2¼E 1þD E ,where D E is a small energy difference characteristic of the dissociative attachment timescale,we obtain,in place of (8.3.2),s att¼0E ,E 1s 0E ÀE 1E 1E 1,E ,E 20E .E 28>><>>:(8:3:5)8.3ELECTRON COLLISIONS WITH MOLECULES 249wheres 0%p m M R 1=2e 4pe 0E 1 2(8:3:6)The factor of (m =M R )1=2roughly gives the fraction of excited states that do not auto-detach.We see that the dissociative attachment cross section rises linearly at E 1to a maximum value s 0D E =E 1and then falls abruptly to zero.As for dissociation,E 1can depend strongly on the nuclear separation R ,and (8.3.5)must be averaged over the range of E 1s corresponding to the ground state vibrational motion;e.g.,from E thr to E 0thr in Figure 8.7a .Because generally D E (E 0thr ÀE thr ,we can write (8.3.5)in the forms att %p m M R 1=2e 4pe 0 2(D E )22E 1d (E ÀE 1)(8:3:7)where d is the Dirac delta ing (8.3.7),the average over the vibrational motion can be performed,leading to a cross section that is strongly peaked lying between E thr and E 0thr .We leave the details of the calculation to a problem.Polar DissociationThe process,e þAB À!A þþB Àþeproduces negative ions without electron capture.As shown in Figure 8.7d ,the process proceeds by excitation of a polar state A þand B Àof AB Ãthat has a separ-ated atom limit of A þand B À.Hence at large R ,this state lies above the A þB ground state by the difference between the ionization potential of A and the electron afﬁnity of B.The polar state is weakly bound at large R by the Coulomb attraction force,but is repulsive at small R .The maximum cross section and the dependence of the cross section on electron impact energy are similar to that of pure dissociation.The threshold energy E thr for polar dissociation is generally large.The measured cross section for negative ion production by electron impact in O 2is shown in Figure 8.8.The sharp peak at 6.5V is due to dissociative attachment.The variation of the cross section with energy is typical of a resonant capture process.The maximum cross section of 10À18cm 2is quite low because autode-tachment from the repulsive O À2state is strong,inhibiting dissociative attachment.The second gradual maximum near 35V is due to polar dissociation;the variation of the cross section with energy is typical of a nonresonant process.250MOLECULAR COLLISIONS。

GLOBAL IMPACT INFECTIOUS DESEASE

The Global Burden of Infectious DiseaseIt is clearly evidenced by the severity of the global impact on human lives and the financial burden to society that infection control measures are proving to be woefully inadequate. In addition, current antimicrobial products are contributing to the increasing worldwide threat from antimicrobial resistant organisms.Statistics on Death Rates∙Today more than one quarter of all deaths worldwide are due to infectious disease.1∙Globally, infectious diseases rank as the second leading cause of death, over half of which are children under the age of 5.1∙Infectious diseases are the third leading cause of death in the United States. 1∙Infectious disease is the main cause of death among children 0-4 yrs old, with 63% of all deaths being attributed to infectious disease. 1∙Every three seconds a young child dies, in most cases from an infectious disease. 1∙Every day 3,000 people die from malaria; three out of four of these victims are children.∙ Every year 1.5 million people die from tuberculosis, and another eight million are newly infected. 1∙Drug-resistant bacteria such as MRSA are a growing problem in hospitals worldwide, killing about 19,000 people each year in the United States.∙According to the CDC, about 20 percent of those infected with MRSA die. In the European Union, more than three million people are infected each year, and tens of thousands die from the infections. 1∙According to a Red Cross report dated June 28, 2000 – “during 1999 the number of people who died from infectious diseases was about 160 times greater than the number who died in natural disasters.”Emerging & Reemerging Diseases∙At least 30 previously unknown disease agents have been identified since 1973, including HIV, Ebola, hepatitis C, and Nipah virus, for which no cures are available.∙Emerging and reemerging infectious diseases, many of which are likely to continue to originate overseas, will continue to kill at least 170,000 Americans annually. Many more could perish in an epidemic of influenza, or some other yet-unknown disease.∙The growing mobility of people, and popularity of airline transportation, has amplified the potential for disease to be transmitted to passengers not only during, but also before and after flights. 2∙In 1977, a strain of influenza (A/Texas) was transmitted to 72% of interviewed passengers and crew, all of whom became ill, from a single passenger who had developed flu symptomsshortly after boarding the airplane.3∙TB will likely account for the overwhelming majority of deaths from infectious diseases in developing countries by 2020. 1∙TB killed 1.8 million people across the world in 2008, or one person every 20 seconds. It is not only a problem for less developed countries, but also in the West, where TB has virulently reemerged in the last 20 years.∙China currently has the world's second largest tuberculosis burden, India has the largest burden.∙Dr. Thomas Frieden, director of the U.S. Centers for Disease Control and Prevention states “We are all connected by the air we breathe, and that is why this must be everyone’sproblem.” 1∙In Cambodia, scientists have confirmed the emergence of a new drug-resistant form of malaria, threatening the only treatment left to fight a disease that already kills 1 million people eachyear.∙In Africa, new and harder to treat strains of HIV are being detected in about 5 percent of new patients. HIV drug resistance rates have shot up to as high as 30 percent worldwide.Hospitals∙Half of all patients in intensive care units around the world have infections, in 64 percent of these cases, the lungs were infected.∙In the United States at least 2 million people each year acquire a secondary infection from a hospital visit. 1∙100,000 people die each year in hospital from a secondary infection and NOT from their original complaint. This is equivalent to two jumbo-jet crashes every two days without any survivors.∙Researchers at Duke University in North Carolina stated: “surgical site infections due to MRSA led to charges in excess of $19 million for the group of study hospitals.” Furthermore "Surgical site infections due to MRSA led to a 7-fold increased risk of death, a 35-fold increased risk of hospital readmission, more than 3 weeks of additional hospitalization, and more than $60,000of additional charges compared to uninfected controls."∙In the USA reimbursement for treating nonsurgical hospital-acquired infections is being eliminated. Recently, legislative elimination of payment for treating hospital-acquired surgical site infections has also been proposed.Spread of Infections∙Infectious diseases are caused by pathogens. Pathogens are described as "any biological agent (otherwise known as a germ) that causes disease or illness to its host". Types of pathogensinclude bacteria, viruses, and fungi.∙Infectious human viruses are almost always either airborne or spread by direct person to person contact. They are also transmitted through touching objects that have been infected with a virus.∙Bacteria “divide” every 20 minutes under optimal conditions.∙One bacterium is far too small to be seen without using a microscope. However, in just 12 hours, one bacterium could multiply to more than 8.5 billion!∙ E. coli, salmonella and other bacteria can live up to two hours on surfaces.∙Hot water will not kill bacteria, only temperatures over 140 degrees can kill them.∙The influenza virus is viable for up to 24-48 hours on hard nonporous surfaces, like plastic, and stainless steel. They can be transferred to hands for up to 24hrs.Bio Terrorism∙Disease-causing viruses and bacteria and their genetic material are the predominant materials and tools for genetic engineering.∙Newer techniques such as DNA shuffling, are allowing geneticists to create in a matter of minutes in the laboratory, millions of recombinant viruses that have never existed in billions of years of evolution.∙These new abilities to create novel (new) viruses and bacteria have the potential to be used for the intentional creation of bio-weapons.∙In 2001 a killer mouse virus was created in the course of an apparently “innocent” genetic engineering experiment.FACTS∙The number of car accidents for 2005 in the USA was 6,420,000 (six million four hundred and twenty thousand) which resulted in 42,636 deaths. This is an average 0.66% mortality rate.∙The number of MRSA infections for 2005 in the USA was 94,000 which resulted in 18,650 deaths. This is an average mortality rate of 19.7% mortality rate.You are 30 times more likely to die from a MRSA infection than a car accident.∙All of the wars of the twentieth century are estimated to have resulted in the deaths of 1.1 million combatants and civilians per year.∙Currently infectious diseases are killing 15.4 million people EVERY YEAR…this statistic is fourteen times the number of deaths from all the wars from the twentieth century - combined!Nobel Laureate and microbiologist Joshua Lederberg, stated, “The future of humanity and microbes likely will unfold as episodes of a suspense thriller that could be titled OurWits Versus Their Genes.”Remember Infection IS PREVENTABLESources:1. The Centers for Disease Control (CDC); The World Health Organization (WHO).2. Mangili, A. and M. A. Gendreau (2005). Transmission of infectious diseases during commercial air travel. Lancet 365(9463):989-96.3. Airborne infections on commercial flights. AMA Council on Scientific Affairs. Report 10 June 1998. Accessed August 12,2002.4. Duke University in North Carolina study - methicillin-resistant Staphylococcus aureus or MRSA infections associated withsurgery published in the Public Library of Science journal PLoS ONE。

The impact of globalization on the economy

Globalization has been a buzzword in the business world for several decades now, and its impact on the economy cannot be overstated. The concept of globalization refers to the interconnectedness of markets, industries, and economies across the globe. This interconnectedness has had a profound effect on how businesses operate, how goods and services are produced and distributed, and how economies grow.One of the most significant impacts of globalization on the economy is the increased trade between countries. As barriers to trade such as tariffs and quotas have been reduced or eliminated, businesses have been able to reach new markets and access a wider range of suppliers. This has led to an increase in global competition, which has driven down prices for consumers and forced companies to become more efficient in order to remain competitive.Additionally, globalization has facilitated the movement of capital across borders. Investors can now easily move their money from one country to another in search of higher returns. This has led to greater investment in developing countries, which has helped fuel economic growth in those regions.Furthermore, globalization has also led to the outsourcing of jobs from developed countries to emerging economies where labor costs are lower. While this has been beneficial for companies looking to save on labor costs, it has also contributed to job losses in certain industries in developed countries.On the other hand, globalization has also created opportunities for workers in developing countries by providing them with access to jobs that they may nothave otherwise had. This influx of jobs has lifted millions of people out of poverty and fueled economic development in many parts of the world.In addition to these direct impacts on trade and labor markets, globalization has also had indirect effects on economic policy and regulation. As countries become more integrated into the global economy, they often find themselves having to align their policies with international standards in order to remain competitive. This can lead to changes in areas such as taxation, environmental regulation, and intellectual property rights.While there are certainly many benefits associated with globalization, there are also some drawbacks that need to be considered. For example, some critics argue that globalization can lead to an erosion of local cultures as Western values and products become dominant around the world. Additionally, there is concern that globalization can exacerbate income inequality both within and between countries.Overall, it is clear that globalization has had a profound impact on the global economy over the past few decades. It has led to increased trade flows, greater capital mobility, and changes in economic policy around the world. While there are certainly challenges associated with this process, there is also evidence that it has contributed significantly to global economic growth and development.As we look ahead into an increasingly interconnected world economy，it will be essential for policymakers,businesses,and individuals alike,to carefullyconsider both its benefits,and its potential downsides,in order ti shape a future where all people can benefit from this powerful force called Globalization.。

The Pros and Cons of Globalization

The Pros and Cons of Globalization Globalization is a complex and controversial phenomenon that has had aprofound impact on the world. It has both its pros and cons, and its effects are felt in various aspects of life, including economics, culture, and politics. Inthis essay, I will explore the different perspectives on globalization, examining its benefits and drawbacks, and ultimately, provide a balanced view of this global trend. One of the most significant advantages of globalization is its role in promoting economic growth and development. By opening up markets and facilitating the flow of goods, services, and capital across borders, globalization has led to increased trade and investment, which has contributed to the overall prosperity of many countries. This has resulted in higher standards of living and improved access to goods and services for people around the world. Additionally, globalization has allowed for the transfer of technology and knowledge, which has helped to drive innovation and progress in various industries. Furthermore, globalization has also facilitated cultural exchange and understanding amongpeople from different parts of the world. Through the spread of information, ideas, and values, globalization has led to greater interconnectedness and a more diverse and inclusive global community. This has resulted in the enrichment of culturesand the promotion of tolerance and appreciation for diversity. Moreover, globalization has also created opportunities for people to experience and engage with different cultures, leading to the enrichment of their own lives and perspectives. On the other hand, globalization has also been criticized for its negative impact on local economies and communities. The increased competition from foreign companies and the outsourcing of jobs to lower-cost regions has led to job loss and economic insecurity for many workers. This has resulted in widening income inequality and social unrest in some regions. Additionally, the homogenization of cultures and the dominance of Western values in the global marketplace have led to the erosion of local traditions and identities, raising concerns about the loss of cultural diversity and heritage. Moreover,globalization has also been associated with environmental degradation and the exploitation of natural resources. The increased production and consumption driven by globalization have led to greater pollution and the depletion of naturalresources, contributing to climate change and ecological destruction. Furthermore, the global supply chains and the demand for cheap labor in developing countries have led to poor working conditions and human rights abuses, raising ethical concerns about the social impact of globalization. In conclusion, globalization is a multifaceted phenomenon that has both positive and negative consequences. While it has contributed to economic growth, cultural exchange, and technological advancement, it has also led to economic inequality, cultural homogenization, and environmental degradation. It is important to recognize and address the challenges associated with globalization while harnessing its benefits for the collective good of humanity. Ultimately, a balanced and inclusive approach to globalization is essential to ensure that its impact is sustainable and beneficial for all.。

溢出效应英语

溢出效应英语Here is an essay on the topic of "Spillover Effect" in English, with the content exceeding 1000 words as per your instructions. Please note that the title is not included in the word count.The modern world is a highly interconnected and interdependent one, where the actions of one entity can have far-reaching consequences that extend beyond its immediate sphere of influence. This phenomenon, known as the "spillover effect," has become an increasingly significant consideration in various aspects of our lives, from economics and politics to social and environmental realms. In this essay, we will explore the concept of the spillover effect, its implications, and the ways in which it shapes the global landscape.At its core, the spillover effect refers to the situation where the impact of an event, decision, or action in one area or system spills over and affects other areas or systems that may not have been the primary target or intended recipient of the initial influence. This can occur in both positive and negative ways, and the magnitude of the spillover can vary greatly depending on the specific circumstances.One of the most prominent examples of the spillover effect can befound in the realm of economics. The global financial crisis of 2008, which originated in the subprime mortgage market in the United States, is a prime illustration of how a localized event can have far-reaching consequences. The collapse of the housing bubble and the subsequent ripple effects through the financial system led to a global recession, causing widespread job losses, declines in consumer spending, and a decrease in international trade. This economic spillover effect impacted countries and industries that had little direct involvement in the initial crisis, demonstrating the interconnectedness of the global economy.Similarly, the COVID-19 pandemic has showcased the profound spillover effects that can occur in the realm of public health. The outbreak of the virus in a single region quickly escalated into a global pandemic, with widespread social, economic, and political ramifications. Lockdowns, travel restrictions, and supply chain disruptions in one country had immediate implications for other nations, leading to a global economic downturn, job losses, and social upheaval. The spillover effects of the pandemic have been felt in virtually every aspect of our lives, from education and healthcare to entertainment and personal relationships.Beyond the economic and public health spheres, the spillover effect can also be observed in the environmental domain. The deforestation of the Amazon rainforest, for instance, not onlyimpacts the local ecosystem but also has broader implications for global climate patterns, biodiversity, and the overall health of the planet. The burning of fossil fuels in one region can contribute to air pollution and climate change, which then affect communities and environments far beyond the source of the emissions. The interconnectedness of the natural world means that environmental issues rarely remain localized, and the spillover effects can be profound and far-reaching.In the political realm, the spillover effect is equally prevalent. The rise of populist movements or the implementation of protectionist policies in one country can have significant implications for international relations, trade agreements, and global stability. The decisions made by political leaders can reverberate across borders, influencing the economic and social well-being of other nations. The recent trade tensions between the United States and China, for example, have had a ripple effect on the global economy, affecting businesses and consumers worldwide.The recognition of the spillover effect has led to a growing emphasis on the importance of global cooperation and coordination. Addressing complex issues that transcend national boundaries requires a collaborative approach, where nations, organizations, and individuals work together to mitigate the negative spillover effects and leverage the positive ones. This has become increasingly evidentin the realm of climate change, where international agreements and collective action are crucial to addressing a global challenge that knows no borders.Furthermore, the understanding of the spillover effect has also prompted a shift in the way we approach problem-solving and decision-making. Policymakers, business leaders, and individuals alike are now more cognizant of the potential unintended consequences of their actions and the need to consider the broader implications beyond the immediate context. This has led to the development of more comprehensive and holistic approaches to addressing societal, economic, and environmental challenges.In conclusion, the spillover effect is a fundamental concept that highlights the interconnectedness of our world and the far-reaching consequences of our actions. Whether in the realm of economics, public health, the environment, or politics, the spillover effect serves as a constant reminder that our decisions and behaviors can have profound and often unpredictable impacts on the world around us. By acknowledging and understanding the spillover effect, we can strive to make more informed and responsible choices, fostering a more sustainable and equitable global community.。

50个句子记完的7000单词

50个句子记完的7000个单词1 .Typical of the grassland dwellers of the continent is the American antelope, or pronghorn.1. 美洲羚羊，或你叉角羚，是该大陆典型的草原动物2。

Of the millions who saw Haley' S comet in 1986 how many people will live long enough to see it return in the twenty-flrst century2。

1986 年看见哈雷慧星的千百万人当中，有多少人能够长寿到足以目睹它在二十一世纪的回归呢？3 ，Anthropologists have discovered that fear, happiness, sadness, and surprise are unlversally reflected in facial expressions.3．人类学家们已经发现，恐懊，、快乐，悲伤和惊奇都会行之于色，这在全人类是共通的，4．Because Of its irritating effect on humans, the use Of phenol as a general antiseptic has been largely discontinued4．由于苯酚对人体带有剌激性作用，它基本上已不再被当作常用的防腐剂了，5 ．In group to remain in existence, a profit-making organization must, In the long run, produce something Consumers consider useful or desirable.5 ．任何盈利组织若要生存，最终都必须生产出消費者可用或需要的产品6 ．The greater the population there is in a locality the greater the need there is for water transportation, and disposal Of refuse.6 一个地方的人口越多，其对水，交通和垃圾处理的需求7 ．It is more difficult to write Simply, directly, and effectively than to employ flowery but vague ex pressions that only obscure one’s meaning.7 简明，直接，有力的写作难于花哨，含混而意义模糊的& With modern Offices becoming more mechanized, designers are attempting to personalize them with warmer less severe Interiors.8 ．随着现代办公室的日益自动化，设计师们正试图利用较为温暖而不太严肃的内部装饰来使其具有亲切感·9 ，The difference between libel and slander is that libel is printed while slander is spoken.9 誹谤和流言的区别在于前者是书面的，而后者是口头的10 ，The knee is the joints where the thigh bone meets the large bone of the lower leg10 ．膝盖是大腿骨和小腿胫的连接处“11 ．Acids are chemical compounds that, in water solution, have a Sharp taste, a corrosive action on metals, and the ability to turn certain blue vegetable dyes red11. 酸是一种化合物，它在溶于水时真有强烈的气昧和对金属的腐蚀性，并且能够使某些蓝色植物染料变红I.12 ．Billie Holiday' S reputation as a great Jazz-blues singer rests on her ability to give emotional depth to her songs.12 ．Billie Holiday' s 作为一个爵士布鲁斯乐杰出歌手的名声建立在能够赋予歌曲感情深度的能力。

书虫系列读后感英文

书虫系列读后感英文Stepping into the captivating realm of the Bookworm series by J. K. Rowling, I embarked on an extraordinary literary adventure that sparked my imagination and left an enduring imprint on my mind. Each installment of this beloved children's fantasy series unfolds a tapestry of whimsical characters, enchanting settings, and captivating storylines that transport readers to a world brimming with wonder and magical possibilities.At the heart of the series lies Mildred Hubble, an ordinary yet determined young witch who attends MissCackle's Academy for Witches. Mildred's endearingclumsiness and unwavering optimism serve as a constant source of amusement and inspiration throughout the series. Her journey of self-discovery and the unbreakable bonds she forms with her fellow students create a heartwarming and relatable narrative that resonates with readers of all ages.The series is renowned for its intricate world-building.J. K. Rowling meticulously crafts a magical universe complete with its own unique customs, creatures, and spells. From the bustling streets of Chatsfield to the enchanting grounds of Miss Cackle's Academy, the reader is transported to a realm where the ordinary seamlessly intertwines withthe extraordinary. The vivid descriptions and imaginative details immerse readers in this enchanting world, allowing their imaginations to soar and connect with the characters on a deeper level.The Bookworm series is not merely a collection of entertaining stories; it is a celebration of friendship, courage, and the power of believing in oneself. Through Mildred's adventures, young readers learn the importance of embracing their individuality, overcoming challenges with determination, and cherishing the bonds they forge with others. The series subtly weaves valuable life lessons into its enchanting tales, inspiring young minds to dream bigand strive for greatness.Moreover, the Bookworm series showcases J. K. Rowling's exceptional storytelling abilities. Her writing ischaracterized by its wit, charm, and ability to capture the innocence and wonder of childhood. The series is peppered with hilarious mishaps, heartwarming moments, and suspenseful encounters that keep readers on the edge of their seats throughout each installment. Rowling's ability to balance humor, adventure, and heartfelt emotions creates a captivating reading experience that leaves a lasting impression.Beyond its literary merits, the Bookworm series holds a special place in the hearts of many readers due to its nostalgic charm. For many, it evokes fond memories of childhood and the joy of discovering a magical world through the pages of a book. The series serves as a timeless reminder of the power of imagination and the enduring impact that stories can have on our lives.As I finished the final installment of the series, a sense of contentment washed over me, coupled with a bittersweet realization that my time with Mildred Hubble and the extraordinary world of Miss Cackle's Academy had come to an end. The Bookworm series has left an indeliblemark on my imagination, inspiring me to embrace the wonders of the world and to believe in the power of dreams.。

媒介社会学：主导范式

媒介社会学：主导范式[美]托德·吉特林①（美国哥伦比亚大学新闻学院，纽约，10027）[摘要] 该文系托德·吉特林写于“有限效果理论”主导着媒介研究的1978年。

吉特林首先揭示“有限效果论”转移了人们对媒介机构属性的关注，即它首先是商业组织，一定程度上受制于国家。

其次，从有限效果研究基本假设中的缺陷入手，批评这种研究方法、研究目的以及研究结果对广播电视网、市场调查研究公司、政治候选人有所助益；并从行政管理视角、市场取向及社会民主主义思潮三方面深入分析了有限效果研究成为媒介社会学主导范式的原因。

最后，强调大众媒介研究的社会责任是揭示日益发展的大众媒介如何对政治生活的结构、对社会文化结构以及人们日常的语言、概念、符号产生深远的影响。

[关键词]媒介效果研究；主导范式；行政管理；市场取向；批判的媒介社会学②Media Sociology: the Dominant ParadigmAuthor：Todd GitlinTranslators：Yu Xia, Cao Xun(School of Journalism, Columbia University, New York 10027,USA) Abstract: Todd Gitlin had this article published in 1978 when limited effects theory of communication had become the dominant paradigm in media studies. In his paper, firstly, Gitlin disclosed that the limited effects theory transferred people’s concern from the fact that mass media were commercial organizations, being subject to the government; then, he listed and analyzed the major weaknesses in basic assumptions of this theory, criticizing its methods, objects and findings, which were designed to work for broadcasting networks, marketing research firms and political candidates, and analyzing the reasons that this theory was turned into the dominant paradigm from three aspects including administrative, marketing-orientation, and social democracy; finally, he emphasized the responsibility of mass media studies was to reveal that how the mass media imposed their profound effects on the structures of political, social, cultural, and everyday’s language, concepts and symbols.Key words: Media Effects Research; Dominant Paradigm; Media Sociology二战以来，随着美国大众媒介的所有权日益集中，日常运作日渐集权化，影响的范围扩及全国与现实生活的方方面面，广播机构相对无权的声音在媒介社会学研究中占据主导地[作者简介]托德•吉特林（1943—），美国当代著名的社会学家、政治评论家、小说家，曾任加州大学伯克利分校与纽约大学社会学、传播学方向教授，目前任教于哥伦比亚大学，为该校传播学博士项目的负责人。

高级商务英语阅读11tAmongtheFringers习题测验答案

Unit 11Among the FringersExercises1.Answer the questions on the text:1)Why did the author say that Quebec City would be known as “la capitalemondiale du gaz lacrimogene” (“tear gas capital of the world” ) after his visit to the City?2)Why did the author focus on those with fewer than ten body piercings as hisinterviewees?3)Why did the author compare people on the streets of Quebec to a nuttyJapanese soldier isolated on a Pacific island?4)The author argues that the impact of international institutions on globalisationhas been decidedly modest. To what extent do you think international institutions have an impact on globalisation?5)Why is the policy of ‘diversion and appeasement’ no longer workable andwhat are the factors on which success of such a policy depends?6)Why do supporters of trade oppose unilateral liberalization and how does theauthor refute their arguments?7)What’s wrong with the dispute settlement process in the WTO according tothe article and do you think the author’s argument holds water?8)P lease elaborate on “Market competition is… a discovery process…”9)What does the author imply by saying “Free trade must be sold, not merely asa means to open foreign markets, but as the best policy for Europe regardlessof what other countries do.”?10)What are the lessons Europe can draw from the Quebec Trade Summitaccording to the author?(答案跟第一版相同)2.Fill in each blank of the following sentences with one of the phrases in the listgiven below:1)The program offers nothing significant in the way of financial compensation.2)The oil fields stretch across 32,000 square kilometers from the riverside to thefoot of the mountain.3)He failed to live up to the high expectations of many shareholders and foreigninvestors alike.4)The firm tries to avoid being ignored in the playground, and its chief strategy, isto cling tenaciously to its special relationship with China.5)Those who try to seal themselves off from the digital world will come up withinnumerable inconveniences in future.6)Their strategy is to shift from ideological confrontation to tactical cooperation.7)The key to holding on to a company's employees is "work that challenges aperson's intellect", which is considered to be one o f the “hygiene factors” in human-resource. parlance8)He allegedly took bribes of $2 million in exchange for making loans.9)What they have done is likely to play into the hands of their perceived regionalrivals.10)As a team, the two parties gained ground and became near unbeatable.11)They seem to have no other options, but buy off the firm to ensure corporateprofits.12)It's a set of skills that has become important for the modern manager ascompanies are subject to security from shareholders and the public. subject3. Match the terms in column A with the explanations in column B:A B1) fringe group a) A system of economic doctrines advocating thatgovernments should regulate international trade in order togain competitive advantages and build favorable balancetrade. 32) economic freedom b) Any activity by a government, group or individual tomaintain or restore the environment for the benefit of alllives in the globe including humans. 53) mercantilist assumptions c) A social group holding marginal or extreme views, believingthe current society is unfair and must be changed throughextreme means including violence. 14) dispute settlement process d) A government policy to encourage export of goods throughlow-cost loans, tax relief for exporters, government financedinternational advertising etc. 75) environmental protection e) A national economic strategy to build up a domesticeconomy by emphasizing the replacement of imports bydomestically produced goods. 116) market competition f) The right of individuals and organizations to pursue theirown interests through economic activities under the rule oflaw without intervention from a government or economicauthority. 27) export subsidy g) Investment by citizens, firms of the government of a countryin industries of another one. 128) market system h) Procedures required to investigate a dispute in internationaltrade , to mediate between the two parties concerned, and todecide the outcome of the dispute case. 49) anti-globalization i) Contests in the market between business firms striving for agreater share of a market or for winning the same group ofcustomers. 610) anti-dumping duty j) A systematic process in which there are market players,mainly suppliers and consumers, who interact and make deals.811) import substitution k) Additional tariff levied on imported goods when they aresold to the importing country at a price less than fair value andare found to threaten material injury to industry and market ofthe importing country. 1012) foreign investment l) A grassroots movement opposing to globalization, intendingto counter its trend and harmful effects, and to reformunbridled capitalism. 94. Turn the following into Chinese:任何能吸引世界各国政商界领袖参会的会议自然是全球化的一种象征。

高二英语世界历史中的伟大人物与事件阅读理解25题

高二英语世界历史中的伟大人物与事件阅读理解25题1<背景文章>Alexander the Great is one of the most renowned figures in history. His conquests spanned a vast territory, leaving a lasting impact on the world. Born in Pella, Macedonia, Alexander was the son of King Philip II. From a young age, he showed great courage and leadership.Alexander's army was highly disciplined and skilled. They defeated many powerful kingdoms and empires. His conquests included Persia, Egypt, and parts of India. Along the way, he established many cities and spread Greek culture.One of Alexander's greatest achievements was his ability to blend different cultures. He encouraged his soldiers to marry local women and promoted the exchange of ideas and traditions. This led to a rich cultural synthesis that influenced future generations.Alexander's leadership style was also remarkable. He was known for his bravery in battle and his ability to inspire his troops. He led from the front and was always willing to take risks. His strategic thinking and military genius allowed him to overcome seemingly insurmountable obstacles.The impact of Alexander's conquests was far-reaching. He opened uptrade routes and promoted cultural exchange. His empire became a center of learning and innovation. Many of the ideas and institutions that emerged during his reign had a profound influence on the development of Western civilization.1. Alexander the Great was born in ___.A. AthensB. SpartaC. PellaD. Rome答案：C。

英语阅读考试题型及答案

英语阅读考试题型及答案一、选择题1. What is the main idea of the passage?A. The importance of educationB. The benefits of technologyC. The impact of globalizationD. The role of government答案：C2. According to the author, which of the following is a negative effect of globalization?A. Increased cultural exchangeB. The spread of diseasesC. The promotion of peaceD. The rise of international trade答案：B二、填空题3. The passage mentions that globalization has led to ________ in the job market.A. increased competitionB. decreased opportunitiesC. a lack of diversityD. a surplus of jobs答案：A4. The author suggests that one way to mitigate the negative effects of globalization is through ________.A. international cooperationB. isolationist policiesC. protectionismD. unilateral actions答案：A三、简答题5. How does the author describe the process of globalization? 答：The author describes the process of globalization as the increasing interconnectedness of countries through trade, communication, and cultural exchange.6. What are some of the positive outcomes of globalization mentioned in the passage?答：Some positive outcomes of globalization mentioned in the passage include the promotion of peace, the spread of new ideas and technologies, and increased economic growth.四、判断题7. Globalization has only positive effects on the economy.A. TrueB. False答案：B8. The author believes that globalization can be beneficialif managed properly.A. TrueB. False答案：A五、论述题9. Discuss the potential solutions to the challenges posed by globalization.答：Potential solutions to the challenges posed byglobalization include fostering international cooperation to create fair trade agreements, investing in education to prepare the workforce for a global economy, and promoting cultural understanding to reduce tensions between different societies.10. How can individuals benefit from globalization?答：Individuals can benefit from globalization by taking advantage of the increased availability of goods and services, accessing a wider range of educational and career opportunities, and engaging with diverse cultures to broaden their perspectives and understanding of the world.。

财务管理5(全英文)

13
Outline of Chapter 5
thus stimulating exports and discouraging imports. A country could devalue its currency only with the approval of the IMF. C. In 1971, the fixed exchange rate system was replaced by a system under which the U.S. dollar was permitted to "float.”
2
Outline of Chapter 5
aggressive in their international operations. In fact, this "reverse" investment has actually been occurring at a higher rate in the past few years than has U.S. investment abroad. C. International financial management must take into account not only such traditional topics as capital budgeting and cost of
2. The present managed floating system permits currency rates to move without any specific limits, but central banks do buy and
15
Outline of Chapter 5

bvp's

Dedicated to Prof. W.L. Wendland on the occasion of his 60th birthday
We analyze the h-p version of the bem for mixed Dirichlet Neumann problems of the Laplacian in polyhedral domains. Based on a regularity analysis of the solution in countably normed spaces we show that the boundary element Galerkin solution of the h-p version converges exponentially fast on geometrically graded meshes.
functions. In this way we show that near the corners the solution of the bvp belongs to the countably normed space B 2 ( ). Making use of results by Guo and Babuska for the behaviour of the solution near the edges and the classical result by Morrey for those parts of the domain away from corners and edges we therefore obtain that the solution throughout the domain belongs to B 2 ( ) (see also 23]). Taking traces we deduce in Section 4 the corresponding regularity results for the solutions of the integral equations in countably normed spaces on the boundary of the domain. In Section 5 we introduce the geometrically graded meshes and the subspaces of tensor products of piecewise polynomials used in the boundary element Galerkin scheme. We show exponentially fast convergence for the h-p version of the bem due to the regularity of the solutions of the integral equations in countably normed spaces (see Sections 3 and 4). This result improves corresponding results for the pure Dirichlet and Neumann problems considered in 21]. Throughout the paper C denotes the generic constant taking di erent values at di erent occurences.

Exploring the Benefits of Globalization

Exploring the Benefits of Globalization Globalization has been beneficial in several ways, such as increased access to global markets and improved communication between countries. It has also contributed to economic growth and development, as well as allowing for a greater cultural exchange. Additionally, globalization has facilitated the spread of technology and the sharing of knowledge across international borders. Globalization has also extended the reach of businesses and organizations, allowing them to access new markets and customers. Furthermore, it has allowed for increased collaboration between nations, which can help solve global challenges such as poverty, climate change, and health care. Finally, globalization has resulted in increased consumer choice, as goods and services are no longer limited to just the local market.However, globalization has also resulted in certain drawbacks. It can lead to cultural homogenization, where the same values and products are spread across the world. It may also contribute to inequality, as certain countries may have access to more resources than others. Additionally, globalization can increase environmental damage due to increased production and consumption. Ultimately, it is important to consider the positive and negative effects of globalization when making decisions. Governments and organizations should strive to ensure that globalization is an inclusive process, and that it is used to improve the quality of life for all people around the world. It should also be used in a sustainable way that minimizes environmental damage.。

英语时文30篇

英语时文30篇1. The Rise of Remote Work: A New Era of Productivity or Isolation?随着远程工作的兴起，我们正在进入一个生产力提升或孤立感增强的新时代。

2. Climate Change: The Urgency of Global Action气候变化：全球行动的紧迫性。

3. The Impact of Social Media on Mental Health社交媒体对心理健康的影响。

4. The Future of Education: Embracing Technology in the Classroom教育的未来：课堂上拥抱技术。

5. The Role of Artificial Intelligence in Modern Society人工智能在现代社会中的角色。

6. The Challenge of Affordable Housing in Urban Areas城市地区可负担住房的挑战。

7. The Importance of Biodiversity for a Sustainable Planet生物多样性对于可持续星球的重要性。

8. The Evolution of E-Commerce: Changing Consumer Behavior电子商务的演变：消费者行为的变化。

9. The Power of Renewable Energy in Combating Climate Change可再生能源在对抗气候变化中的力量。

10. The Influence of Pop Culture on Youth流行文化对青年的影响。

11. The Ethics of Genetic Engineering: A Brave New World?基因工程的伦理：一个勇敢的新世界？12. The Digital Divide: Bridging the Gap in Internet Access数字鸿沟：弥合互联网接入的差距。

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a rXiv:as tr o-ph/971290v15Dec1997Imprint of the Global Hubble Flow on Galactic Rotation Curves ∗Philip D.Mannheim Department of Physics,University of Connecticut,Storrs,CT 06269-3046mannheim@ Abstract We identify an apparent imprint of the global Hubble ﬂow on the systematics of galactic rotation curves,and discuss its possible impli-cations for gravitational theory.Even though the astrophysics community is currently engaged in an ex-tremely vigorous debate as to the explicit nature (macho or wimp)of the dark matter which is widely believed to pervade and even dominate the universe,it is nonetheless instructive (even if only to sharpen the dark matter debate itself)to consider the possibility that dark matter may not in fact actually exist (or at least not in such copious amounts),and that the apparent need for it actually heralds the explicit failure of the standard Newton-Einstein gravitational theory on galactic and larger distance scales,viz.precisely ondistance scales which are altogether larger than the solar system one on which the standard theory was ﬁrst established.In order to address this issue it is thus of value to try to identify phenomenological regularities in the data,regularities which may then possibly point in the direction of some other candidate gravitational theory,or which at the very minimum would serve to constrain dark matter dynamics.Perhaps the most startling aspect of dark matter (other than its very ex-istence)is that none is actually needed in the solar system at all,and nor (asnoted in various presentations in these proceedings)is any apparently needed in any sub-galactic system such as a globular cluster or a molecular cloud, with the standard gravity of the known luminous objects in such systems providing a completely adequate accounting of their dynamics.1However, once one goes to galactic systems not only do the Newton-Einstein gravita-tional contributions of the known luminous constituents underestimate the available data,the associated shortfalls are found to be even bigger on even larger distance scales such as those associated with systems which contain large numbers of galaxies.2From this trend it would thus appear that there is some intrinsic scale associated with the systematics of luminous Newtonian shortfalls,and thus we shall seek to extract an explicit one out from galactic data,toﬁnd below that not only is there evidence of such a new scale,but that it intriguingly turns out to be one which is associated with the global cosmological Hubbleﬂow.Given the above trend in the growth of the luminous Newtonian shortfall with distance as we go from galaxies to clusters of galaxies and then beyond, it is thus suggestive to look at the dependence on(radial)distance of the analogous shortfalls within individual galaxies themselves.Thus we shall speciﬁcally analyze HI spiral galactic rotation curves,these being the curves which go out the furthest beyond the optical disk in distance and which pre-cisely provide the primary evidence for the need for galactic dark matter in theﬁrst place.Now while theﬂatness of many of these rotation curves is their immediately most striking and celebrated feature,it is more instructive to look not at the total observed rotation velocities,but rather to look at the discrepancies,i.e.to look at the luminous Newtonian shortfalls themselves.And,indeed,in cases where the total velocities are in factﬂat,since the luminous Newtonian contribution undergoes a Keplerian falloﬀ,it thus fol-lows that the discrepancies themselves must in fact actually be growing with distance in such cases.Now out of the currently available set of33HI spiral galaxies K.G.Begeman,A.H.Broeils and R.H.Sanders(MNRAS249,523 (1991))identiﬁed a subset of11of them as being particularly reliable,a sub-set which contains dwarfs(whose rotation curves are typically actually rising rather than beingﬂat),intermediate spirals(withﬂat rotation curves)and bright spirals(with curves which typically slightly decline),this being a sub-set which contains galaxies which vary in luminosity by a factor of more than 1000.Now it was noted by P.D.Mannheim(ApJ479,659(1997);Found. Phys.26,1683(1996))that even the non-ﬂat rotation curves of the dwarfs and the bright spirals have discrepancies that likewise grow with distance out to the largest distances,to thus make growing discrepancies the most comprehensive qualitative feature of rotation curve systematics.Moreover, on noting that the centripetal accelerations(v2/c2R)last at the last available data points in each of these11galaxies are all found to lie in the surpris-ingly narrow range of1.51×10−30to7.25×10−30cm−1(i.e.surprisingly close given the huge range in luminosity),Mannheim then found that all of these accelerations could be parameterized according to the universal three-component relation(v2/c2R)last=γ0/2+γ∗N∗/2+β∗N∗/R2where the two new universal constantsγ0andγ∗take the numerical values3.06×10−30 cm−1and5.42×10−41cm−1respectively,whereβ∗=1.48×105cm,and where N∗is the total amount of visible stellar(and gaseous)material in so-lar mass units in each galaxy.In addition we now note,that while not being quite as deﬁnitive as the preferred11galaxies in the33galaxy sample,the other22galaxies(listed for instance in R.H.Sanders,ApJ473,117(1996)) have rotation curves which in general again all show a trend of increasing discrepancy with distance.Moreover,for this larger group the centripetal accelerations at the last detected points are all found to fall in the range 1.32×10−30to5.38×10−30cm−1,i.e.just the same narrow range found for the other11galaxies.Since there is nothing signiﬁcant about the last detected data points(they areﬁxed by the sensitivity of the21cm line detectors and not by any dynam-ics within the galaxies themselves),the existence of this empirically found structure for(v2/c2R)last should thus be taken as being phenomenologically signiﬁcant,and it should thus serve as a constraint on all theories of galactic3rotation curves.Moreover,since the numerical value extracted out for the parameterγ0turns out to be of order the inverse of the Hubble radius,the rotation curves would thus appear to be endowed with a cosmological im-print.Further,on recognizing that theγ0/2+γ∗N∗/2term is serving as a linear potential,we thus see that it its inferred numerical value immediately implies that it would be negligible for sub-galactic distances where the lumi-nous Newtonianβ∗N∗/R2term would then dominate,while becoming ever more important on galactic and larger distances scales.The scale associated with this linear potential thus precisely characterizes when there should or should not be any luminous Newtonian shortfall.Now that we have identiﬁed this pattern it is immediately natural to look for a dynamics which might produce it,and indeed Mannheim has noted (as discussed in his above papers which give detailed related references)that its emergence is actually quite natural in fourth order conformal gravity,a fully covariant,pure metric based candidate alternative to standard Einstein gravity.Indeed,what is found there is that the familiar standard gravity Schwarzschild metric exterior to a star of Schwarzschild radius2β∗is gener-alized in conformal gravity to−g00=1/g rr=1−2β∗/r+γ∗r,to thus yield, for a system of N∗stars,the asymptotic(v2/c2R)last=γ∗N∗/2+β∗N∗/R2on large enough distance scales.We thus see that the departure from standard gravity is described by none other than a linear potential.However,unlike Newtonian potentials,linear potentials are not asymptotically negligible,and thus,again unlike Newtonian gravity,it is no longer possible to neglect the gravitational eﬀects due to matter exterior to any system of interest.Thus we need to determine what eﬀect the rest of the matter in the universe might have on motions within individual galaxies.And,quite remarkably,it was further shown that in conformal gravity the entire Hubbleﬂow is found to act on such galaxies just like a universal linear potential term(generated by the scalar curvature k=−γ20/4of a necessarily topologically open cosmology),to give the additional(v2/c2R)last=γ0/2term just as desired.With these two linear potential terms,conformal gravity was then able to yield parameter freeﬁts to the all of the rotation curve data points of the selected11galaxies (i.e.those at all radial distances and not just the furthest ones)without any need for dark matter.3We thus identify an imprint of cosmology on galacticrotation curves,and suggest that it is its neglect which has generated the conventional appeal to dark matter.This work has been supported in part by the Department of Energy under grant No.DE-FG02-92ER40716.00.。

Imprint of the Global Hubble Flow on Galactic Rotation Curves

The Impact of Globalization

Exploring the Concept of Universal Basic Income

The impact of globalization on the economy

Principles of Plasma Discharges and Materials Processing9

GLOBAL IMPACT INFECTIOUS DESEASE

The impact of globalization on the economy

The Pros and Cons of Globalization

溢出效应 英语

50个句子记完的7000单词

书虫系列读后感英文

媒介社会学：主导范式

高级商务英语阅读11tAmongtheFringers习题测验答案

高二英语世界历史中的伟大人物与事件阅读理解25题

英语阅读考试题型及答案

财务管理5(全英文)

bvp's

Exploring the Benefits of Globalization

英语时文30篇

溢出效应英语