lecture-hydrothermal reaction
托福听力tpo69全套对话讲座原文+题目+答案+译文
托福听力tpo69全套对话讲座原文+题目+答案+译文Section1 (2)Conversation1 (2)原文 (2)题目 (5)答案 (7)译文 (7)Lecture1 (10)原文 (10)题目 (14)答案 (16)译文 (17)Section2 (19)Conversation2 (20)原文 (20)题目 (23)答案 (26)译文 (26)Lecture2 (29)原文 (29)题目 (32)答案 (36)译文 (36)Lecture3 (39)原文 (39)题目 (42)答案 (46)译文 (46)Section1Conversation1原文Student:Hi I'm Robert West,we had an appointment.University administrator:You hear about your graduation form right?I'm about to print it out.Student:Oh good,thanks,I was kind of wondering what it is all about,I mean,I’ve completed more than enough courses work to graduate.University administrator:All this is strictly routine,of course you have to finish your course work.But this form is just the administrative checklist.It's our way of making sure you don't have any unfinished university business,like unpaid tuition bills or lab fees that’s sort of thing.Student:Well,I do have an outstanding student loan,but I was told that I don't have to start paying that off yet,not until I get a job,I do have a job interview tomorrow.University administrator:well,good luck with it,but not yourloan,it's not an issue here.Let’s see,the only problem I see is um，what’s this fine for…uh,an overdue CD that you borrow from the music library.Student:Really?I…I checked it out,like three months ago,but wasn’t really for me.University administrator:Oh,you checked it out for a friend？Student:No,for a faculty member actually.We need that music for a play we produced.Uh,professor Williams was our director and I was in the show.Anyway,he’d asked me to borrow the recording from the library.University administrator:Okay,but that still doesn't explain why you didn't return it.Student:Well,he ended up with it.He says he’d return it.And I just assumed that was that.Because I never heard anything from the library.University administrator:That’s all,you used it and you know this.Student:Yeah,Oh,but I did recently move to a new apartment, maybe they did send something.University administrator:Okay,well this should’ve been done in a time in manner.But as they say better late than never,if you return the CD now,you get away with just a late time, which is a lot less than the fee to replace it.Student:Yeah,but it's totally not my fault,so now I have to track down the CD to avoid having to pay this replacement fee.University administrator:Well,yes.I mean it sounds like there was some kind of a mix-up,but the burden is still on you to settle your library account.You know it,it might be that their records are wrong,so first I suggest you go there make sure and then you might have to go talk to professor Williams.Student:Oh,I guess I have no choice.University administrator:Don't worry too much,these things always get sorted out.Student:Yeah,you’re right.It's no big thing,I should be more worried about my job,interview,then about this.University administrator:And when it’s all worked out,come back here for your paper work.题目.Why does the student go to see the woman?A.To make sure he has completed enough course work to graduateB.To find out when his student loan must be paid backC.To pick up an administrative formD.To complain about a library fine2.What is the student's problem?A.He forgot to return some library books.B.He cannot start paying off his student loan yet.C.He paid his graduation fee too late.D.He owes money to the music library.3.Who is Professor Williams?A.The head of the libraryB.The director of a play the student was inC.The student's music professorD.The person who arranged a job interview for the student4.What is the most likely reason the student did not receive the notice from the library?A.He recently moved.B.He has been out of town.C.The library just mailed it the day before.D.The library sent it to Professor Williams.5.What can be inferred about the student when he says this:University administrator:Well,yes.I mean it sounds like there was some kind of a mix-up,but the burden is still on you tosettle your library account.You know it,it might be that their records are wrong,so first I suggest you go there make sure and then you might have to go talk to professor Williams.Student:Oh,I guess I have no choice.A.He is not sure how to respond to the woman.B.He feels he has been treated unfairly.C.He wonders if there is another solution.D.He does not think the woman's suggestions will work.答案C D B A B译文1.学生：嗨！我是Robert West，我们之前有约。
水热合成时间对Cu
DOI: 10.19906/ki.JFCT.2022074水热合成时间对Cu/Ce-Zr 催化水气变换反应性能的影响康玉姝1，王丽宝1,2，李永志3，白 金1，张财顺1，刘道胜1，张 磊1,* ，高志贤1,*（1. 辽宁石油化工大学 石油化工学院, 辽宁 抚顺 113001；2. 中国石化石家庄炼化公司化工运行部, 河北 石家庄 050099；3. 沈阳市生态环境事务服务经济开发区分中心, 辽宁 沈阳 110000）摘 要：以硝酸盐为铈、锆原料，以柠檬酸代替碱类沉淀剂，固定n (Zr ∶Ce)为2∶8，采用水热法合成Ce-Zr 氧化物载体，再通过浸渍法制备Cu/Ce-Zr 催化剂。
通过XRD 、BET 、H 2-TPR 、XPS 等手段对载体和催化剂进行表征，研究水热时间对催化剂结构、性质和水气变换反应性能的影响。
结果表明，催化活性主要与Cu 比表面积、CuO 的还原温度以及催化剂表面氧空位含量有关。
其中，Cu/Ce-Zr-12催化剂的Cu 比表面积较大、CuO 的还原温度较低，催化剂表面的氧空位数量较多，表现出较好的催化活性。
在320 ℃、水气比(W ∶M )为2，体积空速GHSV=6600 h −1的反应条件下，CO 转化率为96.9%，与热力学平衡值97.1%接近。
关键词：水热法；水热时间；水气变换；CeO 2-ZrO 2固溶体中图分类号： O643 文献标识码： AEffect of hydrothermal synthesis time on the performance of Cu/Ce-Zr catalysts forcatalytic water-gas shift reactionKANG Yu-shu 1，WANG Li-bao 1,2，LI Yong-zhi 3，BAI Jin 1，ZHANG Cai-shun 1，LIU Dao-sheng 1，ZHANG Lei 1,* ，GAO Zhi-xian1,*（1. School of Petrochemical Engineering , Liaoning Petrochemical University , Fushun 113001, China ；2. Chemical Operation Department , Sinopec Shijiazhuang Refining and Chemical Company , Shijiazhuang 050099, China ；3. Shenyang Ecological and Environmental Affairs Service Economic Development Zone sub-center , Shenyang 110000, China ）Abstract: Ce-Zr oxide support was hydrothermally synthesized from metal nitrates of cerium and zirconium as the raw materials using citric acid instead of alkali precipitant, and then Cu/Ce-Zr catalyst was prepared by the impregnation method. The support and catalyst samples were characterized by XRD, BET, H 2-TPR, XPS techniques, and the effects of different hydrothermal time on the structure, properties and performance in water-gas shift reaction were investigated. The results show that the catalyst activity is mainly related to the Cu specific surface area, reduction temperature of CuO and the number of oxygen vacancies on the catalyst surface. Among them, the Cu/Ce-Zr catalyst with hydrothermal time of 12 h has a large Cu specific surface area, a lower reduction temperature of CuO, and a large number of oxygen vacancies, so it shows a good catalytic activity. When thereaction temperature is 320 ℃, the molar ratio of water to gas (W /M ) is 2, and the gas space velocity GHSV=6600 h −1,the CO conversion rate is 96.9%, which is close to the thermodynamic equilibrium value of 97.1%.Key words: hydrothermal method ；hydrothermal time ；water gas shift ；CeO 2-ZrO 2 solid solutionCO +H 2O ⇔CO 2+H 2氢气作为合成原料，已应用于合成氨、石油化工等各个领域[1,2]，作为21世纪最具潜能的清洁燃料，氢能具有广阔的发展前景。
大学化学03-lecture-preview
(2)(12.011 amu) %C =
(30.070 amu) = 24.022 amu x 100
30.070 amu = 79.887%
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Stoichiometry
Moles
© 2019 Pearson Education, Inc.
Stoichiometry
Formula Weight (FW)
• A formula weight is the sum of the atomic weights for the atoms in a chemical formula.
• So, the formula weight of calcium chloride, CaCl2, would be
© 2019 Pearson Education, Inc.
Stoichiometry
Combustion Reactions
• Combustion reactions are generally rapid reactions that produce a flame.
• Combustion reactions most often involve hydrocarbons reacting with oxygen in the air.
Molecular Weight (MW)
• A molecular weight is the sum of the atomic weights of the atoms in a molecule.
• For the molecule ethane, C2H6, the molecular weight would be
Keynote lecture
LOOKING AHEAD FROM THE PAST: THE HERITAGE OF CEMENT CHEMISTRYJ. Francis YoungProfessor EmeritusUniversity of Illinois at Urbana-ChampaignThe Proceedings of the International Congresses on cement chemistry document the important scientific advances in the field. This 12th congress is the latest of a line that stretches back to 1919 (see Table 1).Table 1 – International conferences on the chemistry of cementConference Place Year(1st ) General discussion London, UK 1919(2nd) International Symposium Stockholm, Sweden 19383rd International Sympsium London, UK 19524th International Symposium Washington DC, USA 19605th International Symposium Tokyo, Japan 19686th International Symposium Moscow, USSR 19767th International Congress Paris, France 19808th International Congress Rio de Janeiro, Brazil 19869th International Congress New Delhi, India 199210th International Congress Gothenburg, Sweden 199711th International Congress Durban, South Africa 200312th International Congress Montreal, Canada 2007A review of the proceedings of the successive conferences gives a comprehensive view of the development of the field. The large volume of published material in later conferences makes this a challenging task, but an extremely valuable one. I have regularly consulted many of the principal review papers and supplementary communications. In the short time available I would like to review some of the highlights of successive conferences, concentrating more on the earlier ones which may not be as widely available. This view must necessarily be subjective, reflecting my own research interests, but would be duplicated when concentrating on other topicsFirst International SymposiumThe first conference was not designated as such, but a small group of delegates from around Europe gathered in London to participate in “a general discussion” on the setting of cements and plasters. The results were published in the Transactions of the Faraday Society, Vol. 16, pp. 1-68. Among the presentations were papers by Desch, Le Ch atelier, Klein and Rankin.The nature of the setting process was the first great debate of cement chemistry and has been reviewed in detail [1]. On the basis of his work with plaster, Le Chatelier proposedthat setting and hardening was due to the formation of small, elongated crystals of C–S–H which provides a high degree of local cohesion and strength. Michaelis, on the other hand, advanced the theory that it was caused by the d ehydration of an initial hydrogel, which was dehydrated as water was consumed by further hydration. Crystallization processes (e.g. CH) only contributed to long term hardening. These two theories, crystals versus colloids, were the subject of intense debate for about 25 years until the first international symposium in 1919. In the end a compromise was reached that there was an element of truth in both points of view. Desch [2] summed it up as follows:"I think it is very clearly established . . . . that we are dealing largely with a difference in terms; that whether one regards the jelly as a mass of extremely minute interlacing particles or not is not of very much importance. At any rate, the essential point is that in the colloidal substance the particles are extremely small, and therefore the surface forces are very important. When you come to crystals of perceptible size, such as the crystallization of sodium sulfate, the surface forces are very small relatively to the forces of cohesion. In the case of the u ltramicroscopic particles in the colloid, the surface forces are large in proportion to the forces of cohesion, and when that fact is fairly grasped it is seen that there is no great question of fact at issue between the two views." Second International Symposium19 years later the first specifically designated Symposium on the Chemistry of Cements was held in Stockholm in 1938 under the ausp ices of the Royal Swedish Institute for Engineering research and the Swedish Cement Association. The proceedings were published as a separate volume, but it was not designated as part of a series. At this meeting the we can clearly see the elements of mod ern cement chemistry emerging. Bogue [3] presented an comprehensive paper on the constitution of clinker. He discussed equilibrium crystallization, introducing the Bogue equations, as well as the issues of non-equilibrium crystallization and the formation of glass in some detail. He also provided an extended discussion on the issues of unsoundness caused by exp ansions associated with periclase, free lime and C3A.Equally authoritative was Bessey’s [4] summary of the progress that had been made in the systems CaO–Al2O3–H2O and CaO–SiO2–H2O. In the former system the major sulfate-free hydrates had been identified and characterized compositionally, whereas in the latter system the confusion around the exact nature C–S–H was very evident even though there was some progress in characterizing crystalline hydrate phases. Linking these two contributions was a paper by Bussem summarizing the contribution of the new method of x-ray diffraction to understanding the structures of both anhydrous and hydrated phases.Third International SymposiumLondon was again the site of the third International symposium, now recognized as part of the series started in 1919. The emphasis of this symposium, as judged by the number of review papers, was the composition of Portland cement and its phases (7 papers out22) and the characterization of special cements (5 papers). The compositional and structural aspects of the principal components were discussed in detail. The proposed compositional model for alite put forward by Jeffery [5] was still referenced 20 years later [6]. It should be remembered that this work, and that on the other cement compounds, predated the advent of micronanalysis, but despite this handicap the conclusions drawn were essentially confirmed by later experiment.Fourth International SymposiumAs we come closer to the present day the Proceedings become less historical and more relevant to contemporary work. For me the most significant paper in this symposium is that by Powers on the “Physical properties of cement paste” [7]. This is a condensed, yet comprehensive, version of his classical studies spanning a 15-year period. The quantitative relationships that Powers deduced from classical physical chemistry experiments, without the aid of a definitive description of the hydration reactions or the benefits of modern materials characterization techniques, have stood the test of time and, in recent years have been validated by sophisticated computer modeling.Also of note in this symposium were the contributions on hydration of the calcium silicates (Brunauer & Greenberg), hydrothermal reactions (Taylor), and kinetics of hydration (Kondo). These were the first major contributions by these leaders of the modern era. However much of the work reported at Washington was largely overshadowed by the seminal work “The Chemistry of Cements”, edited by Taylor [8] and published only two years later.Fifth International SymposiumAs a young researcher starting out in the field I desperately wanted to go to Tokyo to attend this symposium. Although that wish was not fulfilled, it was to be the catalyst to bring me to the United States when the then President of the Portland Cement Association visited New Zealand, and our laboratory, on his way back from Tokyo. The Proceedings became one of my principal reference works for many years. It ran to five volumes, reflecting the increasing amount of research being done in the field, and reported in a much larger number of supplementary papers. (This trend has further developed in later conferences.) Taken together these papers provided a sharp focus on the directions the field was taking in critical areas. There were several reports of microanalysis of cement phases, which has now become a rou tine tool in experimental work. Easily overlooked was a supplementary paper by Frohnsdorff and co-workers [9], which foreshadowed the computer simulation modelling at NIST 25 years later. Among the most thumbed principal papers in my copy of the Proceedings was the excellent review paper by Guinier and Regourd on the “Structure of Portland cement minerals”, and Taylor’s “Calcium Silicate hydrates”. Principal review papers by Schwiete and Ludwig [10] and Seligman and Greening [11], together with several supplementary papers, on the crystal structures, compositions and properties of hydrated calcium aluminates and ferrites firmly established the chemistry of the AFm phase inhydrated Portland cement pastes. It was also at Tokyo that Kondo [12] first introduced his five stages of hydration of C3S to an international audience.Another review paper that I found very influential was that by Verbeck and Helmuth [13] on the “Structure and physical properties of cement paste” . This paper was less mathematical than Powers’ contribution in Washington, but offered some intriguing insights into how C–S–H behaved under different environmental conditions. Written discussion to this paper by Feldman and Sereda unveiled their ideas about the structure of C–S–H to a major international audience for the first time. During my first years at the University of Illinois every technical meeting in the USA could guarantee hours of animated debate about the nature of C–S–H and the relative merits of the Powers-Brunauer and Feldman-Sereda models. Twenty two years later Taylor [14] suggested that the two models were not incompatible if “…..the nature of the gel porosity [in the Powers- Brunauer model] is reinterpreted ….[to assign] about one third of the gel porosity to the interlayer space, the remainder being microporosity or fine mesoporosity…..The boundary between interlayer space and micropores is ill-defined.” In recent years modern materials characterization techniques applied to the study of C–S–H have the compositional variability of this phase and elements from both models have relevance in the interpretation of experimental data.Sixth International CongressThe Proceedings of this conference were published only in Russian, which has reduced its impact upon subsequent research. The English texts of the papers were available only to delegates.Seventh International CongressThere were several interesting themes developed at Paris. For the first time the rheology of cement pastes was explored in a principal paper by Helmuth, although no commun-ications were presented on this topic. This congress also reported extensively on the many studies to link bulk paste properties with the microstructure of hardened paste and the properties of its constituent hydrates. Principal papers by Sereda, Feldman and Ramachandran and by Wittman highlighted an area of research on the properties of C–S–H that became increasingly important during the 1980s. About 40 communications were presented in this area.Recent work on the early hydration of cement compounds was a small, but important, part of this conference, beginning an intense effort over the next decade to understand how setting, early hardening and microstructure are controlled by initial hydration. Of note was the use of electron optical and analytical methods to characterize these early processes, and the first presentations by Barret and co-workers on their extensive studies on hydrating suspensions. A principal paper by Skalny and Young [15] addressed the rival hypotheses developed to explain the mechanisms of early hydration of C3S: thecontrol of the induction period by either the crystallization of calcium hydroxide or the formation of stable C–S–H. Subsequent work by Nonat and co-workers and by Gartner and Gaidis shows that the latter hypothesis is better able to explain experimental observations [16]. However, stable C–S–H and Ca(OH)2 both share the Ca–OH octahedral layer as a common structural element, so that yet again disparate viewpoints share some elements of commonality.Eight International CongressSeveral themes that were just touched upon at the preceding conference had a much higher profile in Rio. There is an increasing emphasis on the link between microstructure and properties: the paste–aggregate interface(Massazza), the microstructure of hardened cement paste (Diamond), and pore structure and its influence on transport properties (Feldman). Principal reports on all these subjects were presented together with several communications. Also, more attention was given to the chemistry and physics of deleterious reactions.Ninth International CongressAn overarching theme at this conference was the sustainable production of cements and concretes, an appropriate theme for a developing country like India with its immense challenges relating to resources, energy and infrastructure. Congress reports covered the use of low grade fuels and and combustible wastes (Alhuwalia and Page), mineralizers and modifiers during clinkering (Moir and Glasser) and energy conservation and environmental control (Sprung and Delort). For the first time we encounter commun-ications discussing silica fume and DSP cements (reactive powder concretes). MDF cements also feature and these new topics were introduced in a Con gress report by Della Roy.A principal report by Scrivener and Weiker on the “Ad vances in hydration at low, ambient and elevated temperatures” discussed for the first time results from solid state, magic angle spinning NMR spectroscopy to elucidate the evolution of hydration products. It also reviewed the remarkable progress made in characterizing and quantifying microstructure development using a combination of electron microscopy imaging and in-situ microanalysis.Tenth and Eleventh International CongressesThe series returned to Sweden in 1997, but because of the lack of invited review papers giving a broad coverage of progress across the field, this conference has had less impact than others. Nevertheless there were some interesting contributions in submitted papers including several on the new hot topic of delayed ettringite formation.The eleventh congress took place after my retirement and I was not been able to attend the conference and have not seen the published proceedings. Thus I am not able to offer any assessments on the impact of this Congress.What will future Congresses report on?I have been asked to offer my thoughts about will be the future directions in cements research. The only thing that I can confidently predict is that my predictions are most likely to be wrong. We now understand the complex processes of hydration of cement quite well and the application of mod ern materials characterization techniques are rapidly increasing the level of detail of that understanding. However I see three important areas where progress is already being made and will continue to advance.The first area is sustainability in concrete construction and here the key is service life prediction, where we will continue to make significant progress. Designing structures for 50-year or 100-year service life is already a reality, although our approach is probably not optimal. Over the past ten years we have greatly increased our ability to probe and predict the internal conditions within hydrating concrete and to appreciate how the external conditions affect this. The relationship of pore structure to transport properties has been a major advance and I think there are similar advantages in relating C–S–H structure quantitatively to properties such as creep and shrinkage. The routine use of supplementary cementing materials, and the development of more complex ternary blends, demands this. While numerical and pixel-based modeling have become powerful predictive tools, there is a need to link these more closely to fundamental structure-property relationships. I don’t believe that simple lab-based accelerated tests for durability can ever be a successful strategy and we must employ more sophisticated model-based approaches.The ability to be able to quantify the extent to which concrete has responded to external conditions is crucial for the assessment of future life expectancy. I consider thermodynamic modeling to be key to this being done su ccessfully and that further progress should be realized reasonably quickly. However, the kinetic aspects of chemical degradation processes have been largely overlooked, as has the relationships between microstructural breakdown and kinetics.The second area is the need to reduce greenhouse gasses to try to reverse the alarming trends towards global warming that are accepted by an o verwhelming majority of the science community. Although the manufacture of cement is now one of the most thermally efficient of high temperature processes it produces large amounts of CO2 (~1 ton per ton of clinker). We will continue to see more extensive use of supplementary cementing materials to reduce the carbon footprint. I expect to see further development of modified Portland or non-Portland cements, and the pioneering of alternative manufacturing processes that sequester the evolved CO2.The third area is the evolution of controlled in situ production of concrete using field computers continually monitoring embedded sensors, which report on the progress of hydration and microstructure development. These same computers will predict the expected physical and engineering performance of the concrete for the medium and long term using computer simulation models, which have already been used to design the appropriate concrete mixture. The computer determines, as necessary, any changes to the curing regimen to bring properties back to required values for the predicted service life. There is also a fourth area that I hope will flower in the future that will allow us to harness cementitious reactions to produce high performance materials using near-ambient processing temperatures. MDF and DSP cements are early examples of this, but this strategy has yet to capture the attention of the materials science community. I believe there is enormous potential in this approach to produce materials for applications where conventional ceramics are used, but where high temperatures are not encountered, but it will up to the next generations of cement scientists to take it to another level. Whatever happens I can safely predict that the progress in the next 35 years will be as exciting, as stimulating and as challenging as in the past 35 years that it has been my privilege to enjoy.References1. RH Bogue, The Chenistry of Portland Cement, Rheinhold, 1947.2. CH Desch, Trans. Farad. Soc., 1918-19, 14 1-7.3. RH Bogue, Proc. (2nd) ISCC, pp. 59-98, Ingeniorsvetenskapsakakademien,Stockholm, 1938.4. GE Bessey, Proc. (2nd) ISCC, pp. 178-215, Ingeniorsvetenskapsakakademien,Stockholm, 1938.5. JW Jeffery, Proc. 3rd ISCC, pp. 30-55, Cement & Concr. Assoc., London, 1952.6. FM Lea, The Chemistry of Cement and Concrete, 3rd edn/1st Amer. edn, ChemicalPubl. Co., 1971.7. TC Powers, Proc. 4th ISCC, Vol. II, pp. 577-608, Natl. Bur. Stds, Washington DC,1962.8. HFW Taylor, ed., The Chemistry of Cements (2 vol.), Academic, 1964.9. GJC Frohnsdorf et al. Proc. 5th ISCC, Vol. II,pp. 321-7, Cement Assoc. Japan,Tokyo, 1968.10. HE Schweite, U. Ludwig, Proc. 5th ISCC, Vol. II, pp. 37-66.11. P Seligman, NR Greening, Proc. 5th ISCC, Vol. II, pp. 179-19912. R Kondo and S. Ueda, Proc. 5th ISCC, Vol. II, pp.203-247.13. G. Verbeck, RA Helmuth, Proc. 5th ICCC, Vol. III, 1-31.14. HFW Taylor, Cement Chemistry, Academic, 1990.15. JP Skalny, JF Young, Proc. 7th ICCC, Vol. I p. II-1/3, Editions Septima, parius,1980.16. E. Gartner et al. in Structure and Performance of Cements, 2nd edn., J Benstedand P Barnes, ed., Spon Press, 2002.。
应用化学专业英语及答案
黄冈师范学院2009—2010学年度第一学期期末试卷考试课程：专业英语考核类型：考试A卷考试形式：闭卷出卷教师：杨一思考试专业：化学考试班级：应用化学200601 一、Translate the following into English（20 points）1.过滤2.浓缩3.结晶化4.吸附5. 蒸馏6．超临界的7.二氯甲烷8.热力学平衡9.亲电性10.表面张力11.共轭的12.酮13.平衡常数14.丙基15.丁基16.亚甲基18.环己酮19.同位素20.标准熵二、Translate the following into Chinese（20 points）1. methyl propanoate2. rate constant3. ethyl methyl ketone4. free energy5. radical intermediate6. isobutyl methyl ether7. 3-chloropropene8. primary radical9. n-propyl bromide10. bond energy 11. circulating electrons12. local magnetic fields13. tetramethylsilane14. mass to charge ratios15 phenylamine16 amide17. amine18. nucleophile19. perchlorate20. carbocation三、Translation the following into chinese （40 points）A卷【第1页共 3 页】1. We can see why benzene is stable: according to resonance theory, the more resonance forms a substance has, the more stable it is. Benzene, with two resonance forms of equal energy, is therefore more stable and less reactive than a typical alkene.2. Membranes can be defined essentially as barrier, which separates two phases and restricts transport of various chemicals in a selective manner. A membrane can be homogenous or heterogeneous, symmetric or asymmetric in structure, solid or liquid, can carry a positive or negative charge or be neutral or bipolar. Transport through a membrane can be effected by convection or by diffusion of individual molecules, induced by an electric field or concentration, pressure or temperature gradient. The membrane thickness may vary from as small as 100 micron to several mms.3. The most common industrial adsorbents are activated carbon, silica gel, and alumina, because they present enormous surface areas per unit weight.A surface already heavily contaminated by adsorbates is not likely to have much capacity for additional binding, but further heating will drive off these compounds to produce a surface with high adsorptive capacity.Temperature effects on adsorption are profound, and measurements are usually at a constant temperature. Graphs of the data are called isotherms. Most steps using adsorbents have little variation in temperature.A卷【第2页共 3 页】4. In the absence of peroxides, hydrogen bromide adds to peopene via the Markovnikov pathway to yield isopropyl bromide. In the presence of peroxides, however, the order of addition is reversed, and the product is n-propyl bromide; the addition in this case is said to be anti-Markovnikov. This is interpreted in terms of initiation of the addition reaction by bromine atom, rather than by a proton, as is the case for electrophilic addition.四、Translate the following paragraphs into Chinese（20 points）1．Benzene and its derivatives can be nitrated using a mixture of concentrated nitric and sulphuric acid. The temperature must be controlled to prevent more than one nitro-group going in.2. Benzene can be made to react with halogen derivatives using aluminium chloride as a catalyst. This is called a Friedel-Crafts reaction.can be sulphonated by reacting it with fuming sulphuric acid(oleum). The benzene reacts with sulphur trioxide in the oleum.benzene is converted into ethylbenzene by reacting it with ethene. The ethylbenzene (also called styrene) is used to make polystyrene.黄冈师范学院2009—2010学年度第一学期期末试卷参考答案及评分标准考试课程：专业英语考核类型：考试A卷考试形式：闭卷出卷教师：杨一思考试专业：化学考试班级：应用化学200601 一、Translate the following into English（20 points）2. concentrate 4. adsorption chlorideequilibriumtensionconstant14. propylmagneticresonanceentropy二、Translate the following into Chinese（20 points）1. 丙酸甲酯2. 速率常数3. 甲乙酮4. 自有能5. 自由基中间体6. 异丁基甲醚7. 3-氯丙烯8. 伯自由基9. 正丙基溴化10. 键能11.循环电子12. 局部电磁场13. 四甲基硅烷14. 质荷比15.苯胺16.氨基化合物17.胺18亲核试剂19.高氯酸盐20.碳正离子三、Translation the following into chinese （50 points）1．依据共振理论，物质具有的共振式越多就越稳定。
chapter 8-2013,4,18--4,22
Second Law of Thermodynamics
•The universe is composed of the system and the surroundings. The second law of thermodynamics states that the entropy of the universe increases for spontaneous processes.
Example: entropy change for a reaction
A decrease in the number of gaseous molecules leads to a decrease in the entropy of the system. When the NO(g) and O2(g) in (a) react to form the NO2(g) in (b), the number of gaseous molecules decreases. The atoms have fewer degrees of freedom because of the formation of the new N—O bonds, and the entropy decreases. Entropy change for a reaction.
In general: Sgas> Sliquid > Ssolid • In general, entropy increases when
– – – – Gases are formed from liquids and solids. Liquids or solutions are formed from solids. The number of gas molecules increases. The number of moles increases.
水热法合成在可见光照射下具有高催化活性的纳米TiO_2催化剂_英文_
A rticle ID :0253-9837(2004)12-0925-03C ommu nication :925~927Received date :2004-08-23. First author :TANG Peisong,male,born in 1975,PhD student.Correspondin g author :HONG Zhanglian.Tel/Fax:(0571)87951234;E -mail:hong zhanglian@.Fou ndation item :Supported by the Education Department of Zhejiang Province (20030625),SRF for ROCS,SEM (2003-14)and the Na -tional Natural Science Foundation of China (50272059).Preparation of Nanosized TiO 2Catalyst with High Photocatalytic Activity under Visible Light Irradiation by Hydrothermal MethodTANG Peisong,HONG Zhanglian,ZHOU Shifeng,FAN Xianping,WANG Minquan(Dep ar tment of Mater ials Science and Engineer ing ,Zhej iang U niver sity ,H angz hou 310027,China)Key words:nanosize,titania,photocatalysis,hydro thermal method,visible light C LC number:O643 Document code :AT he semiconductor T iO 2is the most important photocatalyst for the degradation of pollutants.Anatase T iO 2has a large band gap of 3 2eV that re -quires powerful UV light to initiate the photocataly tic reactions.Many modification methods such as metal ion doping,composite semiconductors and metal layer modification have been used to extend the light ab -sorption of the catalyst to the v isible lig ht region buthave little effect [1~4].Surface sensitization withdyes [5]is not practical in application as most dyes sel-fdegrade easily.Therefore,the preparation of TiO 2w ith good w avelength response in the visible light re -g ion and high photocatalytic activity for pollutant degradation using natural sunlight is an important g oal in TiO 2photocatalysis.In this paper,the nanosized T iO 2catalyst with high photocatalytic activity under visible light irradia -tion was prepared by the hy drothermal method [6]w ith acetone as the solvent.A high pressure reactor (WH F -0 25L,Weihai Reactor Ltd.,China )and analytical reagent grade tetrabutyl titanate,acetone and alcohol were used.The hydrothermal reaction w as carried out at 240 for 6h at a heating rate of about 2 /min.The T iO 2pow ders were taken out from the cooled reactor and w ashed 4times w ith alco -hol,and dried at 50 for 24h in a vacuum dryer.T he dried powders were calcined at 180,250and 365 for 2h,respectively,and samples TiO 2-1,T iO 2-2and T iO 2-3were obtained.T he TiO 2samples were characterized by XRD,T EM and UV -Vis spectroscopy on an XD -98X -ray diffractometer,a JEM -200CX electron microscopeand a Lambda 20U V -Vis spectrometer,respectively.Diffuse reflectance spectra (DRS)were measured by PELA -1020w ith an integrating sphere accessory in a Lambda 900U V -Vis spectrometer.The photo -catalytic experiments w ere carried out in a sel-f assem -bled instrument w ith a metal halog en lamp (HQI -BT ,400W/D,OSRAM ,German)as the irradiation source.In a 50ml g lass cup,20mg TiO 2and 10ml methyl orange solution (20mg/L)w ere mixed and dispersed by ultrasonic treatm ent for 5m in follow ed by 30m in irradiation w ith a JB450filter (Shanghai Optical Glass Corp.,China)that transmits visible lig ht of w avelength above 450nm.UV -Vis spectra of the upper transparent solution w ere measured after centrifugation.The photocatalytic efficiency w as ca-lculated using the absorption intensity of the standard methyl orange solution at 464nm.Our test revealed that the adsorption amount of methyl orange on the surface of TiO 2-3in darkness w as about 2%,w hich is within the measurement error of the degradation ef -ficiency and would not affect the result of the pho -catalytic efficiency.The removal rate of COD Cr was determined w ith potassium dichromate. The physico -chemical properties and photo -catalytic efficiencies of different T iO 2samples are list -ed in Table 1.It can be seen that TiO 2-1and TiO 2-2show ed high photocatalytic efficiencies of about 99%and 90%,respectively,under visible light illumina -tion ( 450nm),w hile T iO 2-3and P25gave very low degradation rate.The reduction of the COD Cr value for TiO 2-1was above 90%,w hich was m uch higher than that for commercial P25.All the pre -第25卷第12期催 化 学 报2004年12月Vol.25No.12Chinese Jour nal of CatalysisDecember 2004pared TiO 2sam ples could deg rade methyl orange com -pletely under direct visible light irradiation w ithin 10min.Even T iO 2-3w ith a low deg radation rate undervisible light could fully deg rade methyl orange,andits photocatalytic efficiency w as hig her than that of P25.T able 1 Physico -chemical properties and photocatalytic efficiencies for methyl orange degradation of different TiO 2s amplesCatalyst T reatment condition Crystal type Average grain size (nm)M ass loss at 120~500 (%)Reflection ratio at 500nm (%)Degradati on rate(%)T i O 2-1180 ,2h pure anatase 10 3.6521.399 1T i O 2-2250 ,2h pure anatase 10 2.3739.690 3T i O 2-3365 ,2hpure anatase 110.3290.416 2P25*80%anatase+20%rutile300.6094.38 3*Commerical pow der,Degussa Ltd.Fig 1 DRS spectra of d ifferent TiO 2samples (1)T iO 2-1,(2)TiO 2-2,(3)T iO 2-3,(4)P25As show n in Table 1,all the prepared TiO 2sam -ples had sim ilar crystal phase and average grain size,but their mass loss at 120~500 w as different.T here ex isted difference in DRS behaviors of different T iO 2samples.The reflection ratios of TiO 2-1,T iO 2-2,T iO 2-3and P25at 500nm w ere 21 3%,39 6%,90 4%and 94 3%,respectively.Fig 1show s the DRS spectra of different T iO 2samples.In the v isible light reg ion,T iO 2-1and TiO 2-2had similar DRS spectra w ith a low reflection ratio.How ever,both T iO 2-3and P25showed a high reflection ratio.In g eneral,the sum of transmittance,reflectance and absorbance is about 100%[7]when light irradiates a solid surface.The transmittance could be neglected in the T iO 2samples,which had a thickness of about 4mm for the DRS measurements.Therefore,a hig h reflectance in the DRS spectra meant a low ab -sorbance for the TiO 2catalyst.The results imply that the v isible light absorption of TiO 2-1and TiO 2-2w as higher than that of either TiO 2-3or P25.It is inter -esting that w ith the decrease in mass loss at 120~500,the absorbility and the photocatalytic degradationefficiency of T iO 2decreased.Fig 2 TG -DT A cu rves of TiO 2-1Generally,the crystal structure and grain size are the tw o key factors affecting TiO 2photocatalytic activity.Nevertheless,the difference in photocatalyt -ic efficiency of TiO 2-1,TiO 2-2and T iO 2-3under vis -ible light cannot be explained by either the crystal type or grain size.Fig 2show s TG -DTA curves of TiO 2-1.The mass loss at 120~500 on the TG curve corresponded to the exotherm ic peaks at 185,276and 377 on the DTA curve.The mass loss and ex othermic peaks were likely the result of the desorp -tion and oxidation of adsorbed organic materials on the TiO 2surface [8].Thus,we suggest that the high degradation efficiency should orig inate from the ad -sorbed organic materials.The function,kind and amount of these organic materials are still not clear at present,but they are very im portant and need to be clarified.One possibility is that they have a similar role to surface sensitization dyes w hich have high ab -926催 化 学 报第25卷sorption for visible lig ht.The high absorption under v isible lig ht irradiation,which is in good agreement w ith the high visible lig ht degradation efficiency,may be due to an appropriate amount of adsorbed or -g anic materials for both T iO 2-1and T iO 2-2.As for T iO 2-3,most of the surface organic residues desorbed after treatment at high tem perature,thus the ab -sorbance for visible light absorption and the degrada -tion efficiency under visible light dropped to a low v alue comparable to that of P25.T he adsorbed organ -ic materials are thermally stable under 250 heat treatm ent (TiO 2-2)w hile most of the dyes are easilydecomposed and have no surface sensitization effect after such a hig h temperature treatment process. In summary,nanosized TiO 2catalyst with ad -sorbed organic material residues on its surface synthe -sized by the acetone hydrothermal method showed high photocatalytic efficiency and good thermal stabi-lity under visible light irradiation.This nanosized T iO 2pow der is a prom ising photocatalyst for use un -der sunlight irradiation.References1 L insebig ler A L,Lu G Q ,Y ates T Jr.Chem Rev ,1995,95(3):7352 Asahi R,M orikawa T ,Ohw aki T ,Aoki K,T aga Y.Sci -ence ,2001,293(5528):2693 K han S U M ,A-l Shahr y M ,Ingler W B Jr.Science ,2002,297(27):22434 Z hao W,M a W H,Chen Ch Ch,Zhao J C.J A m Chem Soc ,2004,126(15):47825 R amakrishna G ,Ghosh H N.J Phy Chem B ,2001,105(29):70006 Wu M M ,L ong J B,Huang A H ,Luo Y J,Feng S H,Xu R R.L angmuir ,1999,15(26):88227 F ang R Ch.Spectrosco py of Solids (In Chinese).Hefei:Press U niv Sci T echnol China,2001.1-58 Deng X Y ,Cui Z L,Du F L ,Peng Ch.Wuj i Cailiao X ue -bao (Chin J I norg M ater ),2001,16(6):1089水热法合成在可见光照射下具有高催化活性的纳米TiO 2催化剂唐培松, 洪樟连*, 周时凤, 樊先平, 王民权(浙江大学材料与科学工程系,浙江杭州310027)摘要:以丙酮为溶剂,采用水热法在240 合成了表面吸附有机物的纳米T iO 2粉体光催化剂,并采用XR D,T EM ,U V -V is 和DRS 等技术对催化剂进行了表征.结果表明,合成的纳米T iO 2催化剂在可见光激发下具有良好的光催化降解甲基橙的性能和较好的热稳定性.经180,250和365 热处理后,催化剂的晶型和尺寸没有变化,但催化剂表面吸附的有机物发生了明显变化.催化剂表面吸附的有机物、可见光波段的光响应性能和可见光下催化降解甲基橙的效率之间存在良好的关联性,催化剂表面吸附适量的有机物可提高纳米T iO 2催化剂在可见光波段的光响应性能,从而提高其在可见光照射下催化降解甲基橙的性能.关键词:纳米,二氧化钛,光催化,水热法,可见光(Ed YHM)927第12期唐培松等:水热法合成在可见光照射下具有高催化活性的纳米T iO 2催化剂。
哈佛大学高等有机化学讲义Lecture11
(2) CYCLOADDITION REACTIONS/CYCLOREVERSION REACTIONS:
A cycloaddition reaction is the union of two smaller, independent pi systems. Sigma bonds are created at the expense of pi bonds. A cycloaddition can occur in an intramolecular sense, but it must be between two independent pi systems. Cycloaddition reactions are referred to as [m + n] additions when a system of m conjugated atoms combines with a system of n conjugated atoms. A cycloreversion is simply the reverse of a cycloaddition. Examples:
s Woodward-Hoffmann Theory R. B. Woodward and R. Hoffmann, The Conservation of Orbital Symmetry, Verlag Chemie, Weinheim, 1970. s Frontier Molecular Orbital Theory I. Fleming, Frontier Orbitals and Organic Chemical Reactions, John-Wiley and Sons, New York, 1976. s Dewar-Zimmerman Theory T. H. Lowry and K. S. Richardson, Mechanism and Theory in Organic Chemistry, 3rd Ed., Harper & Row, New York, 1987. s General Reference R. E. Lehr and A. P. Marchand, Orbital Symmetry: A Problem Solving Approach, Academic Press, New York, 1972.
新编化学化工专业英语
前几课翻译链接：/s/1o6qiyuQLesson 10 ThermodynamicsThermodynamics is the physics of energy, heat, work, entropy and the spontaneity of processes. Thermodynamics is closely related to statistical mechanics from which many thermodynamic relationships can be derived.热力学是物理能量，热，工作过程，熵和自发性。
热力学是密切相关的统计力学，热力学关系可以推导出。
While dealing with processes in which systems exchange matter or energy, classical thermodynamics is not concerned with the rate at which such processes take place, termed kinetics. For this reason, the use of the term “thermodynamics”usually refers to equilibrium thermodynamics. In this connection, a central concept in thermodynamics is that of quasistatic processes, which are idealized, “infinitely slow”processes. Time-dependent thermodynamic processes are studied by non-equilibrium thermodynamics.在处理中，系统交换物质或能量的过程，经典热力学不关心这些过程发生的速率，称为动力学。
Lecture_2
Our Atmosphere: A Chemical Perspective
The Secondary Atmosphere
• Several hypotheses exist, which can be broadly classified as solar nebula, solar wind, comet–asteroid and accretion
Our Atmosphere: A Chemical Perspective
• Significant outgassing (the release of gas from the planet’s interior) took place as the intense heating would have led to the dissociation of minerals containing bound H2O and CO2, as well as degassing of physically trapped gases
Our Atmosphere: A Chemical Perspective
The Noble Gases
• So called because of their chemical inertness • These gases provide valuable pointers concerning atmospheric origins and evolution • Except for He (the lightest of the Noble Gases), they cannot readily escape to space
化学反应的基本原理
化学反应的基本原理第2章化学反应的基本原理(Fundamentals of Chemical Reactions)化学是研究物质的组成、结构、性质及其变化规律的科学。
在研究化学反应时，⼈们主要关⼼化学反应的⽅向、限度、速率以及化学反应中所伴随发⽣的能量变化，本章通过对化学热⼒学、动⼒学基础知识的学习，要求掌握化学热⼒学的基本概念、基本原理，能够正确判断化学反应进⾏的⽅向、进⾏的程度以及改变化学反应速率的⽅法。
2.1化学反应中的能量关系任何化学反应的发⽣总是伴随着形式多样的能量变化，如：酸碱中和要放出热量，氯化铵溶于⽔要吸收热量等。
2.1.1热⼒学基本概念（1）体系与环境在研究化学反应的能量变化关系时，为了研究的⽅便，常常把研究的对象与周围部分区分开来讨论。
在化学上把所研究的对象称为体系（system），⽽把体系之外的、与体系密切相关的部分称为环境（surrounding）。
例如：研究在溶液中的反应，则溶液就是我们研究的体系，⽽盛溶液的容器以及溶液上⽅的空⽓等都是环境。
根据体系与环境之间物质和能量的交换情况不同，可以把体系分为以下三类：敞开体系（open system）：体系与环境之间，既有物质交换，⼜有能量交换。
封闭体系（close system）：体系与环境之间，没有物质交换，只有能量交换。
孤⽴体系（isolated system）：体系与环境之间，既没有物质交换，也没有能量交换。
例如：⼀个盛⽔的⼴⼝瓶，则为⼀个敞开体系，因为瓶⼦内外既有能量的交换，⼜有物质的交换（瓶中⽔的蒸发和瓶外空⽓的溶解）；如在此瓶上盖上瓶塞，则此时瓶内外只有能量的交换⽽⽆物质的交换，这时成为⼀个封闭体系；如将上述瓶⼦换为带盖的杜⽡瓶（绝热），由于瓶内外既⽆物质的交换，⼜⽆能量的交换，则构成⼀个孤⽴体系。
体系与环境之间可以有确定的界⾯，也可以是假想存在的界⾯。
体系与环境因研究的对象改变亦可以发⽣改变。
（2）过程和途径体系的状态发⽣变化时，状态变化的经过称为过程(process)。
上海交通大学课程教学大纲
课堂教学和反转课堂
Lectureand Discussion
讨论题
Discussion
掌握授课内容并作报告
Mastering the teaching contentand report
课堂报告
Report
3.考核方式及规定/Grade Composition and Grading Policy
课程简介
Course
Description
This course is for students majored in aerospace engineering. This course introduces fundamentalsof strength and stiffness ofcompositematerials and structures. The contents of the course cover principles of composite material mechanics, introduction to composite, lamina stress-strain relationship, effective moduli and strength of a continuous fiber-reinforced lamina, analysis of lamina hydrothermal behavior, analysis of laminates, hydrothermal effects in laminates,interlaminar stresses, mechanical testing of composites.Moreover, the students are required to self-learn several lecture including manufacturing process and certification etc. After learning this course, the students should master the fundamental design knowledge of composite structures, cultivate the capabilities ofquantitative analysisandlogical thinking, and establish the ability of solving practical problems usingalgorithm design andcomputer programing.
哈佛大学高等有机化学讲义Lecture15
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s The related reaction of 2 ethylenes is nonconcerted: [2 + 2] cycloaddition
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批注本地保存成功开通会员云端永久保存去开通
D. A. Evans
Cycloaddition Reactions: Part–1
s Other Reading Material:
Ultimate_Limits_to_Intercalation_Reactions_for_Lithium_Batteries_Chem_Review_2014
In this review, these phosphates will be first discussed and then compared with the well-studied transition metal oxides. These two systems have quite different electrochemistry; whereas the mixed metal oxides react mostly by a singlephase intercalation reaction, Lix[NiMnCo]O2, the electronically insulating olivine LiFePO4 was thought to react by a twophase reaction, LiFePO4 + FePO4. There have been many challenges with using a two-phase reaction and an electronically insulating solid as a battery electrode, which limited the initial capacities to only ∼0.6 Li.8 These challenges have now been overcome by several breakthroughs, including conductive coatings9 or a redox mediator,10 combined with nanosizing of the material. It was these breakthroughs plus the riveting paper by the Chiang group,11 suggesting, incorrectly as it turned out, that substitution had a major impact on the electronic conductivity, that got the scientific community activated. At the same time, the company A123 successfully commercialized LiFePO4 batteries for portable and stationary systems. However, despite these successes, the reaction mechanism is just now being fully understood, as is the role that defects and metal substitution play. The electrochemical behavior of natural triphylite LiFe1−yMnyPO4 has been determined9c and found to be under 80 mAh/g (<50% of theoretical) before and after a high-temperature carbon-coating treatment, suggesting that impurities might create problems; therefore, all battery cathode materials are synthetic. Although the olivine phosphates have been extensively studied in the laboratory12 and have found commercial application for several large-scale applications, for example, in grid storage in the U.S., and for electric bicycles and cars in China, their relatively low volumetric energy densities have precluded their use in most portable applications including electronic devices and electric vehicles in the US. The layered oxides can have significantly higher energy densities (as shown in Table 1); there are still serious concerns about their safety because of the possibility of oxygen evolution on overcharge, which in the worst case can result in cell rupture and fires. Thus, there is an effort underway to study phosphates and related materials where more than one lithium ion can be intercalated into the lattice, or where magnesium can be intercalated (DOI 10.1021/cr500049y). The research in this area will also be reviewed in this article.
水热制备技术
Bayer法是直接以苛性钠溶液处理铝土矿，使矿 石中氧化铝生成铝酸钠，而矿石中的二氧化硅则成 为不溶性残渣，与铝酸钠溶液分离，将净化后的铝 酸钠溶液进行搅拌分解，再经过滤分离得到氢氧化 铝，经洗涤后焙烧成氧化铝，分离所得的大量苛性 碱溶液称为母液，母液经蒸发再用于处理下一批矿 石。
铝土矿分解的Bayer 过程使得水热制备技术第一次 在工业领域中得用。 Bayer 过程的主要化学反应如下 式所示，反应在温度330oC、压力为250atm条件下， 仅需几分钟就能完成。
自然界中的晶体
水晶
CaF2
CaCO3
Sb2S3
FeS2
祖母绿宝石晶体
海蓝宝石(Aquamarine)
祖母绿(Emerald)
据文献记载，英国地质学家Roderick Murchison 是第一位使用“水热”一词来描述高温、高压条件下 地壳中的岩石矿物形成的学者。
水热制备技术发展历史上具有里程碑意义的事件
4.2.3 密度
液相区
水在不同压力下的温度与密度的关系
300℃时，液相密度为0.75g/cm3, 气相密度 为.05g/cm3。随着T升高，液相密度逐步减小，气 相密度逐步增大。当T=Tc=374℃，液相密度=气 相密度=0.321g/cm3。 当T>Tc时，只有气相存在，称为超临界水或 流体水。当T<Tc时的水称为亚临界水
4.2.2 压力
氢转移反应 同位素
氢转移反应同位素英文回答：Hydrogen transfer reactions are a type of chemical reaction in which a hydrogen atom or a hydrogen ion is transferred from one molecule to another. These reactions are important in various fields, including organic chemistry, biochemistry, and environmental science.In organic chemistry, hydrogen transfer reactions play a crucial role in the synthesis of complex molecules. For example, in the hydrogenation of alkenes, hydrogen atoms are transferred from a hydrogen source, such as molecular hydrogen (H2), to the carbon-carbon double bond of the alkene. This reaction is commonly used in the production of saturated fats from unsaturated vegetable oils.Another example of a hydrogen transfer reaction is the reduction of carbonyl compounds, such as aldehydes and ketones, to alcohols. In this reaction, a hydrogen atom istransferred from a reducing agent, such as sodium borohydride (NaBH4) or lithium aluminum hydride (LiAlH4),to the carbonyl group, resulting in the formation of an alcohol.Hydrogen transfer reactions also play a role in biological systems. For instance, in enzymatic reactions, hydrogen atoms are often transferred between molecules to facilitate various biochemical processes. One such exampleis the action of alcohol dehydrogenase, an enzyme that catalyzes the transfer of a hydrogen atom from an alcoholto a coenzyme, such as nicotinamide adenine dinucleotide (NAD+), resulting in the formation of an aldehyde or ketone.In environmental science, hydrogen transfer reactions are involved in various natural and industrial processes. For instance, in the atmosphere, hydrogen atoms can be transferred between different atmospheric species, such as hydroxyl radicals (OH) and volatile organic compounds (VOCs), leading to the formation of new compounds and influencing the overall composition of the atmosphere.Overall, hydrogen transfer reactions are essential in many chemical and biological processes. They enable the transformation of molecules, the synthesis of complex compounds, and the regulation of various biochemical pathways. Understanding and controlling these reactions is crucial for the development of new drugs, the production of chemicals, and the study of environmental processes.中文回答：氢转移反应是一种化学反应，其中氢原子或氢离子从一个分子转移到另一个分子。
【托福听力资料】托福tpo15听力文本-lecture4
【托福听力资料】托福TPO15 听力文本-Lecture 4众所周知，托福TPO材料是备考托福听力最好的材料。
相信众多备考托福的同学也一直在练习这套材料，那么在以下内容中我们就为大家带来托福TPO听力练习的文本，希望能为大家的备考带来帮助。
TPO 15 Lecture 4 BiologyNarrator: Listen to part of a lecture in a biology class.Professor:OK. We’ve been talking till now about the two basic needs of a biologicalcommunity – an energy source to produce organic materials, you know uh, food forthe organisms, and the waste recycling or breakdown of materials back intoinorganic molecules, and about how all this requires photosynthesis when greenplants or microbes convert sunlight into energy, and also requiresmicroorganisms, bacteria, to secrete chemicals that break down or recycle theorganic material to complete the cycle. So, now we are done with this chapter ofthe textbook, we can just review for the weekly quiz and move on to the nextchapter, right? Well, not so fast. First, I ‘d like to talk about somediscoveries that have challenged one of these fundamental assumptions about whatyou need in order to have a biological community.And, well, there actually were quite a few surprises. It all began in 1977with the exploration of hydrothermal vents on the ocean floor. Hydrothermalvents are cracks in the Earth’s surface that occur, well, the ones we aretaiking about here are found deep at the bottom of the ocean. And these vents onthe ocean floor, they release this incredibly hot water, 3 to 4 times the temperature that you boil water at, because this water has been heated deep within the Earth.Well about 30 years ago, researchers sent a deep-sea vessel to explore the ocean’s depth, about 3 kilometers down, way deep to the ocean floor, No one had ever explored that far down before. Nobody expected there to be any life down there because of the conditions.First of all, sunlight doesn’t reach that far down so it ’ s totally dark. There couldn’t be any plant or animal life since there’s no sunlight, no source of energy to make food. If there was any life at all, it’d just be some bacteria breaking down any dead materials that might have fallen to the bottom of the ocean . And?Student 1 ：And what about the water pressure? Didn ’ t we talk before about how the deeper down into the ocean you go, the greater the pressure? Professor ：Excellent point! And not only the extreme pressure, but also the extreme temperature of the water around these vents. If the lack of sunlight didn’t rule out the existence of a biological community down there then these factors certainly would, or so they thought.Student 2：So you are telling us they did find organisms that could live under those conditions?Professor: They did indeed, something like 300 different species.Student 1 ：But... but how could that be? I mean without sunlight, no energy,no no …Protessor:What they discovered was that microorganisms, bacteria, had taken over both functions of the biological community - the recycling of waste materials and the production of energy. They were the energy source. You see, it turns out that certain microorganisms are chemosynthetic - they don’t need sunlight because they take their energy from chemical reactions.So, as I said, unlike green plants which are photosynthetic and get their energy from sunlight, these bacteria that they found at the ocean floor, these are chemosynthetic, which means that they get their energy from chemical reactions. How does this work?As we said, these hydrothermal vents are releasing into the ocean depth this intensely hot water and here is the thing, this hot water contains a chemical called hydrogen sulfide, and also a gas , carbon dioxide. Now these bacteria actually combine the hydrogen sulfide with the carbon dioxide and this chemical reaction is what produces organic material which is the food for larger organisms. The researchers had never seen anything like it before.Student 2 : Wow! So just add a chemical to a gas, and bingo, you ’ ve got a food supply?ProfessorNot just that! W hat was even more surprising were all the large organisms that lived down there. The most distinctive of these was something called thetube worm. Here, let me show you a picture . The tube of the tube worm is really, really long. They can be up to one and a half meters long , and these tubes are attached to the ocean floor, pretty weird looking, huh?And another thing, the tube worm has no mouth or digestive organs. So you are asking how does it eat? Well, they have these special organs that collect the hydrogen sulfide and carbon dioxide and then transfer it to another organ, where billions of bacteria live. These bacteria that live inside the tube worms, the tube worms provide them with hydrogen sulfide and carbon dioxide. And the bacteria, well the bacteria kind of feed the tube worms through chemosynthesis, remember, that chemical reaction I described earlier.。
托福听力tpo69 lecture1、2、3 原文+题目+答案+译文
托福听力tpo69 lecture1、2、3 原文+题目+答案+译文Lecture1 (2)原文 (2)题目 (5)答案 (8)译文 (8)Lecture2 (10)原文 (10)题目 (14)答案 (17)译文 (17)Lecture3 (20)原文 (20)题目 (23)答案 (26)译文 (26)Lecture1原文So, we've talked about the plates that form the earth crust and their movements and how in some places they're separating. Now, when this happens in the ocean along a middle ocean ridge, some important things can happen, in particular you can get a hydrothermal vent. This is a lot like a geyser except it’s on the ocean floor.A geyser of course is a kind of eruption from underground hot spring. Water that’s been heated up in Earth’s interior, when under pressure, can erupt, sending that water and steam, shooting upwards through crack in the earth. A hydrothermal vent is essentially this same thing, but the water is emitted out of cracks or, or fractures in the ocean floor. If Forms that don't depend on energy from the sun, but depend on chemical energy.But, the vents are also enormous significance for us. From a purely geological perspective, because the chemistry of the oceans is affected by them. To see how, let’s look at the process a little more closely. They typically occur in fields, so you might have an area with a dozen of them, but you need two things to get one of these fields, first, you got haveheat. And you’ve got have fissures in the ocean floor. So, in a vent field, you've got cracks in the ocean floor. And cold water at the bottom of the ocean, we are talking, maybe two degrees Celsius, goes down into them, as it goes underground, it heats up, because in these fields, there are magma chambers, only a few kilometers below the ocean floor.This hot molten rock heats the solid rock above it to as high as five hundred degrees Celsius. And this heated solid rock, then heats the ocean water that flows over it. Now remember, the high pressure of the deep sea, allows water to stay liquid at such a high temperature, so it can reach temperatures of, three or four hundred degrees Celsius.As the water heated, it rises up through other cracks and it shoots up back into the ocean, much like with geyser on land. Now, the important part, is what the water is carrying with it, as it emerges. The heated water draws minerals from solid rock. So, you get dissolved metals in the water, like iron and copper. When the water shoots up and re-enters the cold ocean, it quickly cools and these minerals precipitate out. They’re released and they are deposited into the ocean water, which affects its composition. And it also creates quite a site, these vents have a plume that looks like a smoke, likes smoke that’s coming up out of the vent in the earth.Remember some of the water coming out of the vents is over threehundred degree Celsius. When it’s this hot, it dissolves sulfur, iron and other metals in the rock and it interacts with. when these minerals precipitate out, the water forms of black plume, so these vents are called black smokers. It's the sulfur and metals precipitating out of the water that that's what causes black color.But there are also white smokers, these emit what looks like a white smoke. That's because their water is relatively cool, above one hundred to three hundred degrees. Still pretty warm, but, not warm enough to dissolve sulfur or iron. Instead, they draw off different minerals from rocks. Things like silica and they give off different color, whitish color, when those minerals precipitate out.But in both black and white smokers as the waters emitted in the plume, the mineral that precipitate out, eventually build up around the vent, forming large, tower, like structures or minerals, build up layer upon layer, we call these chimneys, just like a chimney on a house. Different minerals will tend to build up at different places on the chimneys. But, some of the minerals like silica, a form kind of cement, and they hold the whole structure together. So, they can grow quite large and quite quickly. If you can believe it there was one chimney that reached forty-seven meters, that’s like fourteen story It collapsed, but it’s actually now rebuilding.题目1.What does the professor mainly discuss?A. The process by which molten rock can enter the oceanB. The formation of hydrothermal ventsC. The differences between geysers and hydrothermal ventsD. The mineral composition of hydrothermal vent chimneys2.According to the professor, what is the main difference between geysers and hydrothermal vents?A. Where they occurB. What causes themC. The size of their plumesD. The temperature of the water they emit3.What aspect of hydrothermal vents is of most significance to the professor?A. Their role in supporting unusual life formsB. Their role in affecting the chemical composition of the oceansC. Their role in affecting the movement of ocean platesD. Their role in affecting the temperature of ocean water4.What conditions are needed for hydrothermal vents to form?[Click on2 answers.]A. Heated rock beneath the ocean floorB. Rocks on the ocean floor with high mineral contentC. Cracks in the ocean floorD. Strong ocean currents5.What are two differences between black smokers and whitesmokers?[Click on 2 answers.]A. Black smokers emit water at a higher temperature.B. Black smokers are more common than white smokers are.C. Black smokers are found in deeper ocean water.D. Black smokers release different types of minerals than white smokers release.6.What does the professor say about the chimney structures that grow around hydrothermal vents？A. They last only a few years.B. They are formed by a single mineral.C. They can grow very tall.D. Their growth rate depends on the temperature of the water emitted from the vent.答案B A B AC AD C译文我们之前讨论了构成地壳的板块及其运动，以及在某些地方它们如何分离。
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How to make a supercritical fluid?
超临界水的性质
• 在超临界点条件 (374℃， 22.1MPa以上 ) ，水的性质不同于标准状态 Nhomakorabea的性质：
• 密度 g/cm3 静介电常数 电离常数 (kmol/kg)2 粘度 cp 374℃，22.1MPa 0.15 2 10-23 0.03 标准状态 1.0 80 10-14 1.0
Solvothermal synthesis at temperatures of less than 260
oC
is
routinely carried by us using Teflon-lined steel autoclaves. In order to utilise more extreme conditions, more heavily-engineered apparatus is necessary.
Development of hydrothermal processing
A hydrothermal reaction cell, for the collection of neutron diffraction
data from reacting mixtures of solids and liquids.
NaA沸石 NaS沸石
基本类型
4. 离子交换反应：沸石阳离子交换；硬水的软 化、长石中的离子交换；高岭石、白云母、 温石棉的OH-交换为F-。 从籽晶培养大单晶。
• SiO2 单晶的生长，反应条件为 0.5mol/L-NaOH ，温度梯度 410～300C，压力120MPa，生长速率1～2mm/d； • 若 在 反 应 介 质 0.25mol/L-Na2CO3 中 ， 则 温 度 梯 度 410 ～
5. 单晶培育：在高温高压水热和溶剂热条件下，
370C，装满度为70％，生长速率1～2.5mm/d
基本类型
6. 脱水反应：在一定温度一定压力下物质脱水 结晶的反应。
Mg(OH )2 SiO2 温石棉
7. 分解反应：在水热和溶剂热条件下分解化合 物得到结晶的反应。
350 ~370 C ,8~ 23MPa
Hydrothermal reactor
水热、溶剂热合成体系示意图
密封结构 釜体 压力，温度 溶剂 无机分子物种（反应物） 合成添加剂 晶核、产物
9
水热、溶剂热合成中的反应釜
Na2O-Al2O3-SiO2-H2O体 系
合成效率提高 两个数量级
方钠石
Duncan E. Akporiaye, et al.Angew. Chem. Int. Ed. 1998, 37, No. 5
醇盐水解等
13. 烧结反应：在水热和溶剂热条件下，实现烧 结的反应。
制备含有OH-、F-、S2-等挥发性物质的陶瓷材料
基本类型
14. 反应烧结：在水热和溶剂热条件下同时进行 化学反应和烧结反应。
氧化铬、单斜氧化锆、氧化铝－氧化锆复合体制备
15. 水热热压反应：在水热和溶剂热条件下，材 料固化与复合材料的生成反应
• These mild, solvent-mediated, reaction conditions have allowed access to many novel materials with important applications.
• Good examples include zeolites and other microporous materials used in gas separation and shape-selective catalysis, and layered cathode (阴极) materials for use in efficient rechargeable batteries.
水热和溶剂热合成与固相合成反应的差别
• 反应性
• 反应性主要反映在反应机理上：
（1）固相反应，主要以界面扩散为主 （2）水热和溶剂热反应，以液相反应为主 • 反应机制不同导致不同机构的生成 • 即使生成了相同的结构也可能由于最初生成机理的 差异而为合成材料引入不同的“基因”，如液相条 件下生成完美晶体
Hydrothermal chemistry is currently one of the principal methods of synthesis for the preparation of new inorganic materials. The hydrothermal method involves the heating of solid and liquid reagents with a suitable solvent (usually water) in a sealed vessel at temperatures of up to 250C.
• 超临界水是指温度和压力均高于其临界点的稠密流体，
• 在此条件下水具有许多独特的性质：如有机物和氧气、 氮气以及二氧化碳等气体可与超临界水完全互溶
What is supercritical fluid?
Here we can see the seperate phases of carbon dioxide. The meniscus is easily observed
• • • 实验温度高达1000 C，压强高达0.3GPa 制备无机物的单晶 值得指出的是，有的单晶是无法用其它晶体制备方法得到的： 如CrO2的水热合成
超临界水
与标准状态水相比具有一些特殊性质，水中的氢键几
乎不存在。因此，超临界水具有极低的介电常数和良 好的扩散、传递性能，从而具有很好的溶剂化特征。 • 临界点：374℃，22.1MPa
特点
4. 水热和溶剂热的低温、等压、溶液条件，有利于 生长极少缺陷、取向好、完美的晶体，且合成产 物结晶度以及易于控制产物晶体的粒度；
5. 由于易于调节水热和溶剂热条件下的环境气氛，
因而有利于低价态、中间态以及特殊价态化合物 的生成，并能均匀地进行掺杂。
History of hydrothermal synthesis
9. 氧化反应：金属和高温高压的纯水、水溶液、 有机溶剂得到新氧化物、配合物、金属有机 化合物的反应；超临界的全氧化物反应。
Cr H 2O Cr2 O3 H 2 Zr H 2O ZrO2 H 2 Me nL MeLn( Me 金属离子, L＝有机配体)
基本类型
10. 沉淀反应：在水热和溶剂热条件下生成沉淀 得到新化合物的反应。
Hydrothermal reaction and solvothermal reactions 水热与溶剂热合成
南京工业大学 材料学院 徐玲玲
Hydrothermal reaction and solvothermal reactions
• 水热与溶剂热合成是指在一定温度 （ 100 ～ 1000C ）和压强（ 1 ～ 100MPa ） 条件下利用溶液中物质化学反应所进行 的合成。 • 水热合成化学侧重于研究水热合成条件 下物质的反应性、合成规律以及合成产 物的结构与性质。
With an increase in temperature the meniscus begins to diminish
Increasing the temperature further causes the gas and liquid densities to become more similar. The meniscus is less easily observed but still evident
• 超临界水是非协同、非极性溶剂
高温加压下水热反应的三个特征
1. 使重要离子间的反应加速 2. 使水解反应加剧 3. 使其氧化还原电势发生明显变化
作为溶剂时水的性质
在高温高压水热体系中，水的性质将产生变化
• 蒸气压变高
• 密度变低 • 表面张力变低 • 粘度变低 • 离子积变高
hydrothermal
• Although elevated temperatures are used and pressure is generated in the sealed container, the conditions are much less severe than the traditional ceramic methods of solid-state chemistry.
FeTiO3 KOH K 2O nTiO2 n 4,6
基本类型
2. 热处理反应：利用水热和溶剂热条件处理一 般晶体而得到具有特定性能晶体的反应；
人工氟石棉 人工氟云母
3. 转晶反应：利用水热和溶剂热条件下物质热 力学和动力学稳定性差异进行的反应； 长石 高岭石
橄榄石 蛇纹石
特点
1. 研究体系一般处于非理想平衡状态，因此采用非平 衡热力学研究合成化学问题； • 在高温高压下，水或其他溶剂处于临界或超临界状 态，反应活性提高； • 物质在溶剂中的物性和化学反应性能均有很大改变，
因此溶剂热化学反应大异于常态；
特点
2. 由于水热与溶剂热化学的可操作性和可调变性，因 此将成为衔接合成化学和合成材料的物理性质之间 的桥梁；
Once the critical temperature and pressure have been reached the two distinct phases of liquid and gas are no longer visible. The meniscus can no longer be seen. One homogenous phase called the "supercritical fluid" phase occurs which shows properties of both liquids and gases