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Министерство образования и науки Российской Федерации Федеральное государственное бюджетное образовательное учреждение высшего профессионального образования žКузбасский государственный технический университет имени Т.Ф. Горбачева¤

И. В. Губанова, М. М. Герасимцева

LEARNING CHEMISTRY (Изучая химию) Рекомендовано учебно-методической комиссией направления 240100.62 žХимическая технология¤ в качестве электронного издания для использования в учебном процессе

Кемерово 2012


Рецензенты: Шараева Л.В., ст. преп. кафедры иностранных языков Перкель А.Л., председатель учебно-методической комиссии направления240100.62 žХимическая технология¤ Губанова Инна Владимировна, Герасимцева Маргарита Михайловна. Learning chemistry (Изучая химию): методические указания к практическим занятиям и самостоятельной работе по английскому языку для студентов химических направлений очной формы обучения [Электронный ресурс] : И. В. Губанова, М. М. Герасимцева. – Электрон. дан. – Кемерово : КузГТУ, 2012. – 1 электрон. опт. диск (CD-ROM) ; зв. ; цв. ; 12 см. – Систем. требования : Pentium IV ; ОЗУ 8 Мб ; Windows 2003 ; (CD-ROM-дисковод) ; мышь. – Загл. с экрана. Предложены тексты из современных источников и упражнения к ним, содержат необходимую лексику для использования в рамках профессионального общения.  КузГТУ  Губанова И. В.  Герасимцева М. М.

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Данные методические указания предназначены для практической и самостоятельной работы студентов второго курса направлений 240100.62, 241000.62. Цель методические указания – расширить лексический запас студентов по специальности, развить навыки работы с оригинальными иноязычными текстами и умения обобщать полученную информацию. Входящие в состав упражнения помогают студентам достичь этих целей. Составители подобрали тексты из современных источников, выделяя слова трудные с точки зрения произношения, и отобрали лексику, необходимую для использования в рамках профессионального общения. Составители надеются, что данные методические указания также помогут расширить кругозор студентов в области выбранного направления. Список использованных источников: http://www.lenntech.com/periodic/elements/ca.htm#ixzz1cPlGx9Dd http://www.chemistryexplained.com/elements/P T/Rhenium.html#ixzz1cPjzuRK0 http://www.chemistryexplained.com/elements/CK/Helium.html#ixzz1cPjGjXU3 http://www.chemistryexplained.com/elements/CK/Helium.html#ixzz1cPjC5zew http://www.chemistryexplained.com/elements/CK/Helium.html#ixzz1cPjLGXXD http://www.chemistryexplained.com/elements/CK/Helium.html#ixzz1cPjbyKVn

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TEXTS FOR CLASSROOM READING TEXT 1 Pre-reading tasks 1. Consult a dictionary and read the words. Remember their pronunciation inorganic, tnermodynamics, theory, equilibrium, gene, colleague, idea, solution, oscillating, synthesis, biochemistry. 2. Words and phrases to be learnt all-embracing – всеобъемлющий fissile – расщепляющийся honour with – удостаивать provide a contribution – внести вклад witness something – быть свидетелем чего-либо state-of-the-art – современный in somebody's turn – в свою очередь 3. Guess the meaning of the following words Substance, transformation, controlling, process, organic chemistry, classical, physical, to dominate, technology, expert, academician, prehistoric, Homo sapiens, reaction, machine, basis, element, progress, phenomenon, energy, radioactivity, molecule, Nobel Prize, result, A-bomb, principle, temperature, instrument, mixture, composition, technique, material, microscopy, to visualize, atom, to manipulate, parameter, fact, analysis, form, characteristic, fundamental problem, genetic, apparatus, photosynthesis, planet, analytical. EVER SINCE THE 18th CENTURY ... Part 1 Chemistry, by way of a more or less "popular" definition, can be described as a science of transformations of substances and ways of managing, or controlling these processes. This area of research is believed to have taken its start back in the 18th century, when it was

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only inorganic chemistry, and it went into full bloom in the 19th century with the advent of organic chemistry and went into full bloom in the 19th century with the advent of organic chemistry and classical thermodynamics (subdivision of physical chemistry). As for the 20th century, it was dominated, so to speak, by physical chemistry (in its full volume), technical chemistry (also called chemical technology) and biochemistry. A leading expert in the field – Academician Valentin Parmon, Chairman of the Joint Learned Council on Chemical Sciences of the Siberian Branch of the Russian Academy, has shared his views on the achievements of this nearly allembracing science and its future prospects. It was back in prehistoric times that Homo sapiens became acquainted with the first chemical reaction – fire. Ever since chemistry has continued to develop and lavishly "shared" its knowledge with most, if not all, areas of human endeavor. This knowledge is now successfully applied in power engineering (combustion management in thermal machines, etc.), mechanics (concerning the development of structural materials and also providing the basis for thermal engines and their fuels), in nuclear power engineering (nuclear reactions and fissile chemical elements). Geochemistry has been fully submitted to geology, and biology has been "blessed" with the now rapidly progressing biochemistry. But the central achievement of fundamental chemistry at the start of the 20th century was unravelling the phenomenon of radioactivity which made it possible to "bridle" nuclear energy. At the same time a clear picture was obtained of the structure of matter – the molecule and the chemical bonds therein. Studies of molecules led to the advent of quantum chemistry and chemical kinetics (science of the rates of chemical reactions), which took shape in the late 19th century, promoted the progress of the theory of branched chain processes discovered by Academician Nikolai Semyonov (1896 – 1986) in the early 1930s. For this discovery the Russian scientist and his British colleague Sir Cyril Hinshelwood (1897 – 1967) were honoured with a Nobel Prize in 1956. The most significant results of research in this field was the development of the A-bomb and the controlled conduct of, first, nuclear and later thermonuclear explosions. What is more, the development of chemical kinetics led to the birth of what we call the

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activated complex theory which makes it possible to prognosticate the behavior of a specific substance in various reactions. Another area of this science – physical chemistry – had an important role to play in the development of a new field of research – thermodynamics of non-quilibrium processes. Russian researchers provided a tangible contribution to its establishment. In the early 1950s, for example, V. Belousov discovered the first oscillating (altering the color of solution) time-dependent chemical reactions which had been previously regarded as impossible in principle. The 20th century witnessed torrential progress in analytical chemistry: scientists developed the main types of the now state-of-the-art instruments for determining the composition of complex mixtures – the chromatographs. And it is interesting to note that the basic principle of their operation rests on the ideas of the Russian physiologist and biochemist, Mikhail Tsvet (1872 – 1919). Firmly established among research techniques used to investigate the surface of materials is tunnel microscopy which makes it possible not only to "visualize" atoms, but manipulate them as well. Finally, there came one of the latest achievements of physical chemistry – fem-to-second spectroscopy, capable of achieving temporal resolutions of down to 10-15s in which time light can cover a distance of only fractions of a micron. With the help of this method scientists can investigate the movements of individual atoms within reacting molecules. Considerable achievements of fundamental chemistry have also been observed in the field of directional or controlled, fine organic synthesis. Thanks to that specialists can now "engineer" practically any substances with preset parameters (including biologically active ones). This is also promoted by the fact that the chemical analysis theory has now taken body and form. One of the important achievements of chemists in the 20th century was the emergence of biochemistry as a science in its own right. And a number of fundamental problems have been resolved within its framework. One of them has been the development of the theory of heredity which, in its turn, prepared the ground for the biology of genes and genetic engineering. Biochemistry has also made significant progress in determining the characteristics of the apparatus of natural photo-synthesis which ensures the existence of life on this planet.

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4. Say in English Превращение веществ, область исследования, в полном объёме, ведущий эксперт, объединённый учёный совет, сибирское отделение Российской Академии, ядерная реакция, химический элемент, полностью подчиняться, быстро развивающийся, структура вещества, химические связи, обрести форму, процессы в разветвлённых цепях, значительные результаты, разработка атомной бомбы, контролируемое проведение термоядерных взрывов, прогнозировать поведение, меняющий цвет раствора, принципиально невозможный, определение состава сложных смесей, основной принцип, доля микрона, движение отдельных атомов, значительные достижения, заданные параметры, обрести "плоть и кровь", теория наследственности, генная инженерия, высокотемпературная сверхпроводимость. 5. Answer the following questions 1. What was the first chemical reaction for prehistoric man? 2. What areas of human endeavor is chemistry applied in? 3. What was the central achievement of fundamental chemistry at the start of the 20th century? 4. Who was honoured with a Nobel Prize in 1956? 5. What reactions had been previously regarded as impossible? 6. What are the chromatographs? 7. What can scientists investigate with the help of femtosecond spectroscopy? 8. Is it possible now for specialists to "engineer" practically any substance? 9. What problems does biochemistry deal with?

TEXT 2 Pre-reading tasks 1. Consult a dictionary and read the words. Remember their pronunciation Epoch, micro, argument, pioneering, area, to score, current, polyethylene, pressure, renewable, hydrogen.

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2. Words and phrases to be remembered usher in – возвещать deserve much credit – заслужить похвалу angstrom – ангстром terrestrial – земной assert oneself – отстаивать свои права, 3. Guess the meaning of the following words To pioneer, role, benzine, transuranium elements, radiochemistry, isotope, plutonium, plastics, polymer structural materials, polypropylene, polyurethane, nylon, polyester, effective, silicon, germanium, gallium, nanoelectronics, heterogeneous, homogeneous, control, organization, to design, molecular structure, basis, to attack, formula, optical isomer, absolutely identical, distant, natural gas, methane, agricultural, revolutionary, civilization, traditional, alternative, energy, universal, millenium, molecular electronics. EVER SINCE THE 18TH CENTURY ... Part II From among the latest fundamental works of chemical scientists (mid1980s) one should mention high temperature superconductivity. Significant progress has also been made in the development of applied chemistry. Specialists in this field developed a method of in-depth processing of oil, with the pioneering role in these studies belonging to a Russian researcher, Academician Vladimir Ipatyev (1867–1952). He was the first to suggest the idea of conducting industrial processing of oil at great depths with the help of catalytic technologies. In the 1940s Academician Ipatyev pioneered a method of production of high-octane benzines. The 20th century saw the birth and development of new areas of chemical research – the chemistry of transuranium elements and radiochemistry. Physicists and chemical scientists mastered the technologies of isotope separation of most different chemical elements which made it possible to obtain plutonium, separate uranium-235 and, in the final analysis, build a stable raw material base for

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controlled nuclear reactions which ushered in the epoch of nuclear power engineering. The list of achievements scored by chemical scientists in the 20th century obviously includes polymer structural materials. This covers practically all of the plastics in current use, like polyethylene, polypropylene, polyurethane, nylon, polyesters, and the like. Chemical scientists deserve much credit for the development of new and highly effective medicinal preparations, for pioneering the hitherto unknown methods of protecting the environment from the steadily mounting technogenic pressures and for the production of super-pure substances (germanium, silicon, gallium) which are the basis of micro- and nanoelectronics. As for the prospects of development of the chemical science in the new century, Academician Parmon sums up his views in the following way. The central problem of modern-day chemistry consists in the unbelievably large store of concrete knowledge which keeps growing at a faster pace than in other areas of research and is running ahead of the experts' potential for the assimilation of this knowledge. This being so, an urgent task for the near future is to try and systematize the basic elements of the acquired data. And there is also the growing role of computer chemistry which prognosticates the likely results of a newly developed process. Today scientists have at their disposal enough information in order to "replace" the laborious test-tube experiments with computer simulation to help them to decide whether or not a costly experiment is really worth the effort. Rapid progress is lying in store for the chemistry of nanomaterials where the size of the particles obtained amounts to only tens of angstroms. This includes most of the heterogeneous (consisting of microscopically non-homogeneous parts) catalysts which are of great importance for the control of chemical reactions. This area also includes supramolecular chemistry which investigates the organization of major molecular structures (often of polymeric kind) into orderly "tertiary" ones. Specialists are to develop such systems artificially; the "super task" here is to design molecular electronics which can progress only on the basis of nano- and supramolecular chemistry. One of the perennial arguments among the scientific community concerns the problem of the origin of life from dead matter. A 8


problem of such importance cannot be attacked without first having a very clear physical and chemical definition of the phenomenon in question. In Academician Parmon's view the future formula of this kind must include these words: "Life is a form of existence of a catalyst, which..." This idea rests on the confidence that life really represents the functioning of a special type of biocatalysts. This being so, it is essentially important for fundamental chemical science to develop artificial systems which can reproduce natural photosynthesis. Great problems are also in store for applied research. This includes, above all, developing well-controlled methods of synthesis of biologically and physiologically active substances. Specialists know full well that optical isomers (suibstances absolutely identical in composition and even primary structure) can have a different biological impact. But getting them in pure form is quite problematic. Another likely event in the not too distant future will concern a substitution of the raw material base not only in modem power engineering, but in the chemical industry as a whole. Until today this base was oil and petroleum-processing products, and these will soon be replaced with natural gas and methane. Emphasis will also be on the development of the large-scale chemistry of renewable raws, above all biological ones (wood, agricultural wastes, etc.). Academician Parmon also anticipates a revolutionary event for the whole of our terrestrial civilization – a transition to nontraditional (alternative) kinds of energy and energy carriers. In this connection hydrogen will assert itself within a short span of time as a universal and ecologically clean energy carrier. Facing scientists in the new millennium are also some more specific problems of applied chemistry. Thus no broad use has been made so far of coherent laser emissions. A major breakthrough is approaching in the chemistry of silicon and other semi-conductors. The 21st century will set very high standards on chemical research which is one of the basic areas in our cognition of the world and in securing a worthy life for the whole of humanity. 4. Find the equivalents 1. medicinal preparations 2. protecting the environment

a. лазерное излучение b. сырьевая база 9


3. rapid progress 4. size of the particles 5. petroleum-processing products 6. origin of life 7. perennial arguments 8. energy carrier 9. semiconductor 10. laser emission 11. scientific community 12. raw material base

c. нефтепродукты d. полупроводник e. энергоноситель f. медицинские препараты g. быстрый прогресс h. происхождение жизни i. научное сообщество j. защита окружающей среды k. размер частиц l. вечные споры

5. Agree or disagree 1. In the 1940s Academician Ipatyev pioneered a method of production of gold from oil. 2. The technologies of isotope separation ushered in the epoch of nuclear power engineering. 3. Polymer structural materials are the basis of micro- and nanoelectronics. 4. The size of the particles obtained in the chemistry of nanomaterials amounts to only tens of millimetres. 5. Academician Parmon denies that life is a form of existence of a catalyst. 6. It is quite problematic to get optical isomers in pure form. 7. Oil and petroleum-processing products will be soon replaced with natural gas and methane. 8. Hydrogen can't be a universal energy carrier. 9. No broad use has been made of coherent laser emissions. 10. Chemistry is one of the basic areas in our cognition of the world.

TEXT 3 Pre-reading tasks 1. Consult a dictionary and read the words. Remember their pronunciation Diamond, graphite, tetrahedron, hexagonal, rhombohedral, icosahedron, helium, niche, oxygen.

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2. Words and phrases to be learnt spatial – пространственный facet – грань apex – верхушка, вершина trap – ловушка to sustain – поддерживать to draw one's attention – привлечь внимание to branch out – ответвляться 3. Guess the meaning of the following words Crystalline form, chemical element, basic components, configuration, astrophysicist, to identify, electrode, buffer, condensate, start, technology of synthesis, to focus, niche, program, unique substance, ultraviolet, ideal, pathology, hyperactive, effect, process, medicine, to implant, absolute absorbent, electromagnetic, radar, plasmochemical synthesis, theoretician, experimenter, critical national technology. FULLERENES This somewhat puzzling term stands for a special crystalline form of carbon. This chemical element – the basic component of all organic life on our planet – seems to have been investigated down to the finest details in two of its best-known forms – diamond and graphite - which differ by their physical and chemical properties. In the former atoms are "packed" in the form of spatial tetra-hedrons, and in the latter – in hexagonal and rhombohedral laminated structures. Over the past few decades, however, scientists came to question the finality of these two forms of carbon; some suggested the existence of other spatial chemically stable structures of carbon atoms. Speaking in metric terms, one such structure could be an icosahedron whose geometry was originally described by Archimedes. This structure is a hollow spatial configuration which can be compared to a football with a multitude of pentahedral and hexahedral sides, or facets. Its molecule should have the chemical formula of CsO. And after a long search astrophysicists finally traced in the mass spectra of carbon vapor a characteristic peak which suggested the existence of a matching molecule.

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These, however, were but purely theoretical assumptions which could not be confirmed by any practical findings, here on Earth. And it was only in 1985 that a team of American researchers, investigating carbon by what is called the atomic cluster method using laser evaporation, identified for the first time ever as C6O molecule with the help of time-of-flight mass-spectrometer. What is more, in subsequent experiments not only C6O, but also C7O could be identified. More detailed studies of the new substance suggested the existence of a carbon molecule in the form of a closed hexagonal cell, or cage. The latter reminded the investigators of a geodesic dome with 60 apexesa structure brainstormed by the US inventor and architect Richard Buckminster Fuller which was translated into building construction reality at the EXPO-67 in Montreal. This similarity suggested the name for the new molecule which was called – buckminsterfullerene – a mouthfull which was later reduced to just fullerene. However, the unit which helped trace C6O molecules for the first time could be used for analytical studies only, and not for any quantitative isolation of the substance in question. This problem was finally solved in 1990 by the German scientist W. Kretschmer who not only developed an appropriate unit, but also designed a technology for obtaining sample amounts of fullerene. He demonstrated for the first time that using arc discharges with graphite electrodes and helium (as buffer gas), one can obtain carbon condensate containing C6O molecules. That marked the start of what we call fullerene technologies. Within a short span of time researchers were able to discover what were called lower, or base fullerenes (up to 22 atoms) and higher ones (up to 270 atoms), all of them possessing a range of specific properties. Because of all that they were regarded not just a new and challenging object of basic research, but also as the basis for a range of promising applied innovations. Studies of this amazing phenomenon led the researchers to the conclusion that it can be used in some very different areas of science and technology, above all in electronics and optoelectronics, organic chemistry and metallurgy and in the manufacture of tyres and jewellery, to name but a few. And the range of the newly discovered and unique properties of fullerenes continues to grow just as does the scale of their applications.

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With all that, there is but one snag in using this material on a really broad scale, and this is the cost. In 1994, for example, the price of pure C6O fullerene on the world market was 550 US dollars for one gram, and it was 1,600 dollars for C7O. Studies of fullerenes at the Physics Institute (named after L. Kirensky) of the Siberian Branch of the Russian Academy of Sciences (Krasnoyarsk) were initiated in 1992. Dr. G. Churilov, a specialist in plasmotrons, or plasma generators*, offered to his colleaguesphysicists his own experimental unit for the production of this material. It took them two years to make the necessary adjustments before they were finally able to isolate the material from a carbonic jet in the plasma generator. All of these efforts finally led to the development of a very simple and productive, while likewise unique, technology of synthesis of this variety of carbon. The new area of research focused on fullerenes found a most fitting "niche" in the Federal Program of INTEGRATION adopted in this country in 1995. Within the frame-work of this program a Physico-Technological Research Institute was set up with a special chair of plasmo-chemical technologies. And this form of carbon has since caught the attention of scientists in various fields of research. Chemists, for example, focused on ways of obtaining fullerene solutions and their purification, while physicists have been trying to identify this unique substance with the help of electron spectroscopy in the visible, ultraviolet and infrared bands, while medical experts try using them as biological solutions and biophysicists take special interest in their water-soluble complexes. The latter studies provided an incentive for research in a promising area linked with practical uses of the new material in biology and medicine. The point is that fullerenes, having a definite number of non-saturated bonds, are unique objects capable of gaining electrons, and are also ideal components for reactions with free radicals. This makes it possible to use them as "traps" (antidxidants) in the hyperproduction of active forms of oxygen – the predominant mechanism of body ageing and pathologies. Specialists are now studying the effect of various water-soluble complexes, containing both higher and lower fullerenes, upon oxygen metabolism in the blood of patients with different pathologies. It has been demonstrated

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that higher fullerenes are hyperactive and have a strong effect on redox processes in organic compounds. This is very important, for it thus becomes possible to develop new anti-cancer and anti-viral medicines. The results obtained point to a very promising nature of the current studies of fullerenes. For example, a method developed by Dr. G. Churilov, using an HF plasma jet in the range of up to 0.75 m, makes it possible to design various fullerene complexes at the molecular level. These complexes (obtained by introducing various fractions of other substances or combinations thereof into a C6O molecule) may reveal some very unexpected and useful properties. If, let us say, an excited hydrogen atom is implanted into a fullerene structure and fixed therein, the resulting substance can become what we call an absolute absorbent of electromagnetic emissions, so that any object coated with a paint of this kind will become absolutely invisible to radars. Apart from the above, a "sustained" source of plasmochemical synthesis should make it possible to boost the production of fullerenes and cut back their cost. The problem of synthesis of such minute particles is drawing considerable attention and interest on the part of specialists, including theoreticians, experimenters and practical, or applied researchers. This area of research is in the list of what we call critical national technologies, which proves how important and promising it is. At Krasnoyarsk this line of research began with studies of ultra-dispersed diamond powders and has since branched out into many fields, including studies of nanostructures of various materials and some theoretical and practical problems of nuclear engineering. * Plasmotron (plasma generator) – gas discharge unit for generating low-temperature plasma (T = 104 K). 4. Say in English Исследовать до мельчайших деталей, пространственные химически устойчивые структуры, чисто теоретические предположения, атомный пучковый метод, последующие эксперименты, обсуждаемое вещество, короткий промежуток времени, обладать рядом особых свойств, спорный объект исследований, экспериментальная установка, видимый спектр, водорастворимые комплексы, ненасыщенные связи, кислородный 14


метаболизм, противораковые и противовирусные медикаменты, неожиданные свойства. 5. Answer the following questions 1. What forms of carbon do you know? 2. Who identified C6O molecule for the first time? 3. When was C6O molecule identified? 4. In what areas of science and technology can fullerenes be used? 5. Where was a very simple and productive technology of synthesis of fullerenes developed? 6. Why can higher fullerenes be used in development of new medicines? 7. What useful properties do fullerene complexes reveal? 8. What can cut back the cost of the production of fullerenes?

TEXT 4 Pre-reading tasks 1. Consult a dicnionary and read the words. Try to memorize their pronunciation Pyroxene, authenticity, discredit, meteorite, kalininite, nataliite, feorensovite, rare, chromphillite, mica. 2. Words and phrases to be remembered vanadium related color – цвет, связанный с ваннадия spinel group – яркий изумрудный цвет chromium mica – хромовая слюда

присутствием

3. Guess the meaning of the following words Mineral, pyroxene, chemist, vanadium, zinc, chromium, museum, group, mineralogical.

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DISCOVER YOUR MINERAL Some 150 years ago Russian mineralogist, Member of the St. PetersburgAcademy of Sciences, Nikolai Koksharov, made an interesting discovery while visiting a small village, Slyudyanka, on the shore of Lake Baikal in Siberia. What he found was a mineral of an unusual salad color which belonged to the pyroxene group. He named his find "lavrovite" in honor of the then President of the AllRussia Imperial Society of Mineralogy Lavrov. Twenty years later the find was studied for the first time by a team of German chemists. During more than one hundred years since Koksharov's discovery none of the mineralogists who studied the mineral has confirmed the "vanadium-related" color of lavrovite, although the fact that it contains vanadium was common knowledge among experts. Quite recently a team of German chemists have published an article under an intriguing title questioning the "authenticity" of lavrovite. This was followed by a report on a discredit of the very name "lavrovite".The controversy has attracted the attention of Dr Leonid Reznitsky, a research scientist of the Institute of the Earth Crust of the Siberian Branch of the Russian Academy of Sciences (Irkutsk). He and his team visited the site of the original discovery – the village of Slyudyanka in Siberia. What they found there was not only the mineral in question, but five new ones as well. The first of these turned out to be a very unusual one: it belonged to the spinel group which contains zink, chromium and sulphur - a very rare group earlier encountered only in meteorites. The mineral was given the name of "kalininite" in honor of a scholar who studied the Pribaikalye (near Baikal) region – Professor Pyotr Kalinin of the Moscow Institute of Geological Prospecting. The second mineral in the group – and contrary to the claims of the German scientists – was vanadium pyroxene. Dr. Reznitsky called it "nataliite" after a prominent Siberian geologist Dr. Natalya Frolova. The third of the newly discovered mineral also features an unusual composition – some of its chromium is replaced with) antimony (such compound was found for the first time). It was given the name of "florensovite" in honor of Nikolai Florensov the founder of the Institute of the Earth Crust of the Siberian Branch of the Russian Academy of Sciences, Corresponding Member of the Academy. 16


The fourth and fifth of the newly discovered minerals can be described as varieties of vanadium spinel and rare chromium mica. The latter is an analog of muscovite mica in which aluminum is replaced with chromium that gives the mineral its beautiful brightemerald color. And it was called "chromphillite". Dr. Reznitsky's fellow partner in nearly all of the discoveries is Corresponding Member of the Russian Academy Yevgeny Sklyarov – Director of the Institute of the Earth Crust of the Siberian Branch of the Russian Academy. Over the past few decades the Institute's scientists have discovered more than 20 new minerals. In addition to those mentioned above, seven were discovered by a leading researcher of the same Institute Alexander Konev, another five (including charoite – a fine stone of a violet color) by Vera Rogova, and still another seven by researchers from the Vinogradov Institute of Geochemistry – Vladimir Ivanov, Yevgeny Vorobyev and Nikolai Vladykin. And the search continues now, adding to Slyudyanka's unique record of more than 200 years as a "natural" mineralogical museum. 5. Answer the following questions: 1. Where did the interesting discovery of minerals take place? 2. What minerals does the spinel group contain? 3. What does "Lavrovite" mean? 4. Who discovered more than 20 new minerals? 5. Where did discovery of the rare chromium take place? 6. Nikolai Florensov – what is he? 7. What minerals belong to the pyroxene group?

TEXT 5 Pre-reading tasks 1. Consult a dictionary and read the words. Remember their prononciation. Ketone, application, heterocyclic, tautomerism, cis-tran-isomerism, aminodienone, aminopolyenone, aminovinyl, comprehensively, accessible, conjugate.

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2. Guess the meanings of the following words Electron-donor, electron-acceptor, fundamental, tautomerism, cistrans-isomerism, monograph, traditional, chemical transformation, methyl group, polyene, carbonyl, co-amino, aminopolyenones, aminovinyl, diketones, isoxazoles, nitriles, alkoxy. METHODS FOR THE SYNTHESIS OF CONJUGATED ω-AMINO KETONES Conjugated ω-aminoketones represent a vast class of organic compounds, which draw attention of researchers engaged in various fields. Owing to their high reactivity, these compounds find application in the synthesis of various biologically active heterocyclic systems, natural products, dyes and light-sensitive materials. The presence in ω-amino ketones of electron-donor and electron-acceptor groups separated by conjugated double bonds makes them convenient models for investigations into fundamental theoretical problems such as the nature of chemical bond, excitation, transfer of electrons along the chain of conjugation, colour, sensitivity to various types of external treatment, tautomerism, cis-trans-isomerism, etc. This review surveys the data on the synthesis of β-enaminoketones, δ-aminodienones and conjugated ω-aminopolyenones of various structures. Methods for the synthesis of β-aminovinylketones have been studied fairly comprehensively; they were discussed in reviews and in a monograph published in the 70s and 80s. In recent years, traditional methods for the synthesis of β-aminovinylketones have been modified to increase the yields of the target products and to simplify the experimental procedures. The methods of regio- and stereospeciftc synthesis of enamino ketones containing additional functional groups are being rapidly developed now. The review covers those methods which either are very convenient and readily accessible or involve unusual chemical transformations such as reactions of β-diketones with ammonia or amines, reactions of unsaturated alkoxy ketones with amines, reductive cleavage of isoxazoles, condensation of acid nitrites with methyl ketones, modification of β-aminovinylketones with the use of their lithium salts, and reactions with amide- or lactam acetals

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with compounds containing an active methyl group or a methylene unit. As a rule, the conventional methods cannot be used to synthesise conjugated δ-aminodienones and, especially, polyene ω-amino ketones containing more than two conjugated double bonds between the NMe2 and CO groups. Several specific methods are described for this purpose. Data on the structures and properties of the compounds synthesised are given. Considerable attention is paid to conjugated ω-aminopolyenones. Methods for the synthesis of these compounds have been developed only recently. A specific type of these compounds is represented by α, ά-bis (ω-aminopolyenyl) ketones containing two polymethyl chains linked by a carbonyl group. These compounds exhibit unusual spectral – luminescence properties. Several recent studies have been devoted to the synthesis of conjugated ω-aminoketones containing a heterocyclic fragment, which influences appreciably the physicochemical properties of these compounds. 4. Say in English Фундаментальная теоретическая проблема, донор, акцептор, химические преобразования, метил-кетон, модификация раминовинил кетона, соли лития, активная метиловая группа, метиленовый элемент, как правило, обычные методы, полиметиленовая цепь, карбонильная группа, физико-химические свойства. 5. Answer the following questions 1. What is the gist of fundamental theoretical problems? 2. What do traditional methods for the synthesis of β-aminovinyl ketones consist of? 3. What is the difference between the NMC2 and CO groups? 4. Do these compounds exhibit unusual spectral luminescence properties? 5. Where are alkoxy ketones used with amines and methyl ketones with ω-amino ketones? 6. What influences the heterocyclic fragment? 19


TEXT6 Pre-reading tasks 1. Consult a dictionary and read the words. Remember their pronunciation Conductor stylus (needle), nanotechnology, electric current conductor, datum (a) resolving power to keep a tab 2. Guess the meaning of the following words Microscope, conductor, an injector, scanning tunnel design, physics, chemistry, object, modification, digital video disks, model base, lenses, microelectronic chemistry, vacuum, to examine, service system, atom-power microscope, varieties of graphite, semiconductors, voltage, tunnel microscopes, gene engineering, orthodox. MICROSCOPE SCANS ATOM Using a regular optical microscope, we can inspect objects down to 0.25 mm in size, while its electronic counterpart allows us to make out details equal to 0.1 nanometers (nm), with nanometer being a billionth part of a meter. Hence a new trend in science – nanotechnology, which caters to a range of disciplines from molecular technology and gene engineering to solidstate physics, electrochemistry and microelectronics. Since here one deals with magnitudes on the scale of molecules and atoms, microscopes with much higher resolving power become necessary. Orthodox models are not satisfactory to this end. In 1981 two Swiss scientists, T. Bining and G. Rohrer, designed the world's first scanning tunnel microscope, an achievement that won them a Nobel Prize in 1986. With it we can observe atoms singly, and in assigned points at that. The main sounding element, or probe, of this microscope is an electric conductor stylus (needle) made of tungsten or platinum alloys. Here's how this microscope works. Fixed voltage is applied to the needle that scans the surface of an object and to the object itself; after the needle and the object have approached each other to a distance of decimal fractions of an angstrom, a tunnel current starts flowing between them – hence the name of the microscope, a tunnel 20


microscope. This current is sustained at a constant value with the aid of a servo system which either lifts or lowers the scanner depending on the relief of the surface. A computer keeps a tab on these movements and processes the data thus obtained; thereupon one can inspect the object at required resolution. Yet such tunnel microscopes have certain constraints on their employment. By and large, they are used in high (fine) vacuum. Otherwise, say, in the air or in water only particular varieties of graphite and some lamellar semiconductors can be scanned at atomic resolution. The main constraint: the examined surface should be an electric current conductor. (In 1986 a second generation of sounding microscopes – atom-power ones – entered the stage. The scanning microscope unit has a scanner, a measuring head and a cantilever as essential components. A computer, too, is important: it processes the data and flashes the results on the display. Depending on what kind of operation is carried out in particular and on the size of an object, the scanner either moves this object at a desired pace or controls the cantilever's movements. The latest models are equipped with a pitch engine to move the object under the microscope back and forth. This is a high-precision manipulation taking account of decimal fractions of a micron. It thus becomes possible to scrutinize one and the same site of the surface for days on end, which is a necessary procedure when dealing with sluggish processes. The measuring heads allow to vary the operational modes and obtain high-resolution images (even at atomic resolution); besides, we can measure more than 20 different characteristics of examined samples and modify their surface (in what we term the lithography modes). Yet it is the cantilever needles that are the most essential part of a modem high-performance scanning microscope. They had their second birth in 1990 when methods of silicon micromechanics were suggested for their production. That was a modified classical procedure of microelectronic technology with the use of doping, oxide layer formation and photolythographic processes. Selective etching is of particular importance for the making of cantilever needles, for it becomes possible to manufacture actually identical needles to a tolerance of several units on the nanometer scale. Such needles are 21


fastened on beams which, in their turn, are made to preassigned thickness either by doping silicon with boron or phosphorus to required depth or by sputtering adequate film structures. So scanning cantilever microscopes give an insight into many characteristics of materials. However, the end result directly depends on a modification of needles. For instance, those with a currentconducting surface are used for measuring the relative distribution of surface resistance and capacity as well as the electric characteristics of subsurface structures. Conductor probes supplied with dielectric coating are employed for determining the distribution of subsurface magnetic fields and capacity. Needles coated with high-strength materials (boron nitride, diamond-like coats, etc.) are good for determining the surface hardness. And probes with a chemically modified structure identify and interpret the distributions of adhesive forces; using such probes, we learn to what extent the surface of an object is homogeneous. The above examples do not cover all the possibilities of probing (sounding) microscopy. But they are enough to show that many cantilever modifications are needed to get to know all the various characteristics of objects. It takes time to replace cantilevers and find an appropriate one among many; indeed, it is hardly possible to choose the right cantilever and fix it at the right time and place. That is why multiprobe cartridges are designed: each cartridge is supplied with dozens of needles with different coatings and different characteristics. New-generation microscopes possess superhigh resolution enabling them to scan not only atomic lattices but individual atoms as well. Furthermore, they are capable of modifying various surfaces and changing their structure on the nanometer scale. A subtle, miniature piece of work! Say, the portraits and biographies of all Russians (150 million) drawn this way could be fitted into a slate only 3x3 cm large. Such high-power microscopes are a must in submicron electronics, microbiology, in polymer production (quality inspection and identification of materials obtained) for the optical industry. The application range of these unique apparatuses keeps expanding, and they are quite indispensable in many areas. For instance, in testing the quality of eye lenses, which is a rather sophisticated procedure: being transparent, such lenses should be placed into a water solution for 22


observation. The only nondestructive method available today is through sounding microscopy, for it allows to keep the lens surface intact. The manufacture of digital video disks is yet another nonalternative application domain of such scanning microscopy. Today these disks are made by die-stamping. And since the dies used in such stamping are of magnetic material, nickel in particular, no other methods but sounding microscopy are good for checking their surface. Thus the new generation of scanning microscopes supplied with probes (cantilevers) has a good future in physical and metrological research alike. 3. Answer the questions 1. When can we inspect objects down to 0.25 mm in size? 2. What new trend of science do you know? 3. Who designed the first scanning tunnel microscope? 4. What is the main sounding element of this model? 5. How does needle scan the surface? 6. What is the name of this microscope? 7. What is the current sustained with? 8. What does the computer do? 9. How can you inspect the object? 10. What are the constraints of the microscope?

PART II TEXT 1 Pre-reading tasks 1. Consult a dictionary and read the words. Remember their pronunciation Hydrogen, helium, manuscript, alpha, beta, nucleons, neutrons, protons, isotope, deuterium, atom. 2. Remember the following words big bang – большой взрыв particle – частица 23


primordial matter nucleus (pl nuclei) abundance escape isotope deuterium hydrogen decay

– первый, изначальный, базовый – ядро – доступность – улетучиваться – изотоп – дейтерий –водород – разлагаться, разложение

3. Translate the following words into Russian, defining parts of the speech Origine – originate, exist – existence, nucleus – nuclear – nucleon, cool – cooling, abundance – abundant. 4. Translate the sentences, paying attention to the modal verbs 1. Many of the elements that make up Earth and the people on it had to be created in the nuclear furnaces inside stars and were only released once the star reached the end of its life. 2. It seemed unfair to the Greek alphabet to have the article signed by Alpher and Gamow only, and so the name of Dr. Hans A. Bethe (in absentia) was inserted in preparing the manuscript for print. 3. "The Origin of Chemical Elements", it described a process by which all of the known elements in the universe could have come into existence shortly after the big bang. 4. Alpher and Gamow (with a little help from Bethe) set out a vision of the early universe in which all matter was a highly compressed "soup" of neutrons, some of which were able to escape and decay into protons and electrons as the universe expanded and became less dense. 5. They believed that these new protons could then capture neutrons, together making deuterium nuclei – an isotope of hydrogen that has one proton and one neutron. 6. They then extrapolated this idea and said that all that had to be done to create heavier nuclei was the capture of another nucleon. 5. Read the text and trnslate it with a dictionary

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ON THE ORIGIN OF THE CHEMICAL ELEMENTS We take it for granted that there exists a periodic table with numerous elements (at last count, 118) from which we can construct the world around us. But when the universe began with a big bang, it started out with no elements at all. Many of the elements that make up Earth and the people on it had to be created in the nuclear furnaces inside stars and were only released once the star reached the end of its life. In fact, only light elements, like hydrogen and helium, were created at the start of the universe. We can use our knowledge of how particles react to work out how these elements formed just a few minutes after the big bang. Alpher, Bethe, Gamow … "It seemed unfair to the Greek alphabet to have the article signed by Alpher and Gamow only, and so the name of Dr. Hans A. Bethe (in absentia) was inserted in preparing the manuscript for print". George Gamow, The Creation of the Universe (1952) When Ralph Alpher defended his PhD thesis in 1948, over 300 people came to watch. Thesis defences are not usually a source of so much excitement, at least not beyond the defender’s immediate family, but this one was different. Before finishing his PhD, Alpher, along with his supervisor George Gamow, had written and published a paper arguing that the Big Bang would have created hydrogen, helium and other elements in certain abundances. Gamow, ever the humorist, felt it was inappropriate to publish a paper with author names so similar to "alpha" and "gamma" without including a "beta" – luckily, Gamow’s friend Hans Bethe was happy to oblige, and had his name added to the paper. Bethe did look over the manuscript and later worked on theories that made up for the shortcomings of the initial paper. The paper was published in Physical Review on April 1st 1948. Titled "The Origin of Chemical Elements", it described a process by which all of the known elements in the universe could have come into existence shortly after the big bang. It built on previous work by Gamow that suggested the elements originated "as a consequence of a continuous building-up process arrested by a rapid expansion and cooling of the primordial matter" – in other words, different atoms

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were made by adding one nucleon at a time to the nucleus, before the process was stopped when the universe became too cool. Alpher and Gamow (with a little help from Bethe) set out a vision of the early universe in which all matter was a highly compressed "soup" of neutrons, some of which were able to escape and decay into protons and electrons as the universe expanded and became less dense. They believed that these new protons could then capture neutrons, together making deuterium nuclei – an isotope of hydrogen that has one proton and one neutron. They then extrapolated this idea and said that all that had to be done to create heavier nuclei was the capture of another nucleon. But it’s a little more complicated than that. Their idea works for elements up to helium – and does produce hydrogen and helium, which together make up 99% of the matter in the universe, in the correct proportions to explain their abundances – but it fails when you try to put five nucleons together. There is no stable isotope of any element that has five nucleons. Alpher's and Gamow's theory relied on using each element as a stepping stone to the next, so it was stopped in its tracks by this piece of information. Nevertheless, it was an important step in the right direction, and did describe most of the universe by virtue of the fact that hydrogen and helium make up such a large portion of it. The theory was recognised as significant at the time, too. Among the 300 people in the room at Alpher’s thesis defence, it seems, were the Washington Post. After his presentation, they ran an article with the headline "World Began in 5 Minutes, New Theory". 5. Find more information about the origin of chemical elements and make your presentation

TEXT 2 Pre-reading tasks 1. Consult a dictionary and read the words. Remember their pronunciation Nucleosynthesis, atomic, neutral, cosmologists, baryon, deuteron, photon, nitrogen, relic, technically, quarks, % (per cent). 26


2. Words to be remembered relic – след, остаток, реликт fuse – плавить predict – предсказывать amount –количество emit – испускать density – плотность set of reactions – цепочка реакций bypass – обходить, проход noble gases – благородные газы side effect – побочный эффект eclipse – затмение fluctuation – колебание, неустойчивость come across – натолкнуться, наткнуться evidence – свидетельство light element – легкий элемент sparse – редкий baryon – 3. Translate the following words into Russian, defining parts of the speech Fuse – fusing – fusion, emit – emission, form – formation – forming, dense – density, combine – combination, 4. Translate the sentences, paying attention to participles 1. Protons were technically the first nuclei (when combined with an electron they make a hydrogen atom) and deuterons were the second. 2. When the tritium nucleus comes across a proton the two can combine into a helium nucleus with two protons and two neutrons, known as He-4. 3. Using the baryon density predicted by big bang nucleosynthesis, the total mass of the universe would have been 25% helium, 0.01% deuterium and even less than that would have been lithium. 4. The nuclei formed in big bang nucleosynthesis had to wait a long time before they could team up with electrons to make neutral atoms. 5. Read the text and translate it with a dictionary

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BIG BANG NUCLEOSYNTHESIS Since Alpher, Bethe and Gamow published their paper, cosmologists have done a lot more work on the formation of the light elements in the early universe. The process now has a name big bang nucleosynthesis. In the first few seconds after the big bang, the universe was very hot and dense, making it fully ionised – all of the protons, neutrons and electrons moved about freely and did not come together to make atoms. Only three minutes later, when the universe had cooled from 1032 to 109 ¿C, could light element formation begin. At this point, electrons were still roaming free and only atomic nuclei could form. Protons were technically the first nuclei (when combined with an electron they make a hydrogen atom) and deuterons were the second. Deuterons are the nuclei of deuterium and are made when protons and neutrons fuse and emit photons. Deuterons and neutrons can fuse to create a tritium nucleus with one proton and two neutrons. When the tritium nucleus comes across a proton the two can combine into a helium nucleus with two protons and two neutrons, known as He-4. Another path that leads to helium is the combination of a deuteron and a proton into a helium nucleus with two protons but only one neutron, He-3. When He-3 comes across a neutron, they can fuse to form a full helium nucleus, He-4. Each step in these reactions also emits a photon. Photon emission can be a slow process, and there is a set of reactions that take deuterons and create helium nuclei faster because they bypass the emission of photons. They start by fusing two deuterons and the end result is a He-4 nucleus and either a proton or a neutron, depending on the specific path. Lithium and beryllium were also made in very small amounts. This whole process was over 20 minutes after the big bang, when the universe became too cool and sparse for nuclei to form. The abundance of the light elements can be predicted using just one quantity – the density of baryons at the time of nucleosynthesis. Baryons are particles made with three quarks, such as protons and neutrons. Using the baryon density predicted by big bang nucleosynthesis, the total mass of the universe would have been 25% helium, 0.01% deuterium and even less than that would have been 28


lithium. These primordial abundances can be tested, and, of course, have been. Nowhere in the universe is helium seen with an abundance less than 23%. This is a major piece of evidence for the big bang. The nuclei formed in big bang nucleosynthesis had to wait a long time before they could team up with electrons to make neutral atoms. When neutral hydrogen was finally made 380,000 years after the big bang, the cosmic microwave background (CMB) radiation was emitted. Alpher and his colleague Robert Herman predicted the existence of the CMB in the late 1940s, when they realised that the relic radiation would be a side effect of the recombination of electrons with atomic nuclei. The CMB now provides us with a way to double check our working with an independent measurement on the baryon density. By looking at fluctuations in the CMB, we find a baryon density that would give the correct light element abundances – it seems we really do understand what went on only a few minutes after the universe began. 6. Read the overview of the text and translate it OVERVIEW Helium is a member of the noble gas family. The noble gases are the elements in Group 18 (VIII A) of the periodic table. The periodic table is a chart that shows how the elements are related to one another. The noble gases are also called the inert gases. Inert means that an element is not very active. It will not combine with other elements or compounds. In fact, no compounds of helium have ever been made. Helium is the second most abundant element in the universe. Only hydrogen occurs more often than helium. Helium is also the second simplest of the chemical elements. Its atoms consist of two protons, two neutrons, and two electrons. Only the hydrogen atom is simpler than a helium atom. The hydrogen atom has one proton, one electron, and no neutrons. Helium was first discovered not on Earth, but in the Sun. In 1868 French astronomer Pierre Janssen (1824 – 1907) studied light from the Sun during a solar eclipse. He found proof that a new element existed in the Sun. He called the element helium.

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A superfluid material behaves very strangely. It can flow upwards out of a container, against the force of gravity. It can also squeeze through very small holes that should be able to keep it out. The Nobel Prize in physics for 1996 was awarded to three Americans who discovered superfluidity. They were David M. Lee (1931), Douglas D. Osheroff (1945), and Robert C. Richardson (1937). For an inactive gas, helium has a surprising number of applications. It is used in low-temperature research, for filling balloons and dirigibles (blimps), to pressurize rocket fuels, in welding operations, in lead detection systems, in neon signs, and to protect objects from reacting with oxygen.

TEXT 3 Pre-reding tasks 1. Consult a dictionary and read the words. Remember their pronunciation Triangular, sodium, cleveite, spectrum, spectrum, circle, through, physicist, actually. 2. Words to be remembered sodium – натрий flame – пламя trace – след release – отпускать, выделять device – прибор cleveite – клевеит, нивенит (разновидность уранита) triangular – треугольный 3. Translate the sentences, paying attention to participles and gerunds 1. The flame looks quite different, however, when viewed through a spectroscope. 2. The spectroscope is a device for studying the light produced by a heated object. 3. These basic parts consist of a series of colored lines. 4. They can identify an element by recognizing its distinctive spectral lines even when they can't actually see the element itself. 30


5. French astronomer Pierre Janssen discovered helium after studying the Sun during a full solar eclipse. 6. As he looked at the spectral lines, he was surprised to see some lines that could not be traced to any known element. 4. Read the text and translate it with a dictionary DISCOVERY AND NAMING One of the most powerful instruments for studying chemical elements is the spectroscope. The spectroscope is a device for studying the light produced by a heated object. For example, a lump of sodium metal will burn with a yellow flame. The flame looks quite different, however, when viewed through a spectroscope. A spectroscope contains a triangular piece of glass (called a prism) that breaks light into its basic parts. These basic parts consist of a series of colored lines. In the case of sodium, the yellow light is broken into a series of yellow lines. These lines are called the element's spectrum. Every element has its own distinctive spectrum. The spectroscope gives scientists a new way of studying elements. They can identify an element by recognizing its distinctive spectral lines even when they can't actually see the element itself. This principle led to the discovery of helium. In 1868, Janssen visited India in order to observe a full eclipse of the Sun. A solar eclipse occurs when the Moon comes between the Sun and the Earth. The Moon blocks nearly all of the Sun's light. All that remains is a thin outer circle (corona) of sunlight around the dark Moon. Solar eclipses provide scientists with an unusual chance to study the Sun. Janssen examined light from the Sun with a spectroscope. As he looked at the spectral lines, he was surprised to see some lines that could not be traced to any known element. He concluded that there must be an element on the Sun that had never been seen on Earth. The name helium was later suggested for this element. The name comes from the Greek word helios for "sun." French astronomer Pierre Janssen discovered helium after studying the Sun during a full solar eclipse. Chemists did not know what to make of Janssen's discovery. Was there an element on the Sun that did not exist on Earth? Had he made 31


a mistake? Some scientists even made fun of (высмеивать, подшучивать) Janssen. For the next thirty years, chemists looked for helium on Earth. Then, in 1895, the English physicist Sir William Ramsay (1852 – 1916) found helium in a mineral of the element uranium. Credit for the earthly discovery of helium is sometimes given to two other scientists also. Swedish chemists Per Teodor Cleve (1840 – 1905) and Nils Abraham Langlet also discovered helium at about the same time in a mineral called cleveite. Ramsay did not know why helium occurred in an ore of uranium. Some years later, the reason for that connection became obvious. Uranium is a radioactive element. A radioactive element is one that breaks apart spontaneously. It releases radiation and changes into a new element. 5. Make a plan and retell the text

TEXT 3 Pre-reading tasks 1. Consult a dictionary and read the words. Remember their pronunciation Temperature, carbon dioxide, neon, scientific, ¿C, ¿F, spectrum. 2. Words to be remembered rate – скорость liquid – жидкость boiling point – точка кипения convert – превращаться, превращать break down – расстраиваться, ухудшаться apply for – применить для freezing point – точка замерзания crust – кора carbon dioxide – оксид водорода give off – отдавать distinct – отчетливый figure – цифра 32


3. Translate the following words into Russian, defining parts of the speech. Radiate – radioactivity – radiation, scientist – scientific, produce – produced, nature – naturally, vary – variation, spectrum – spectral, study – studying. 4. Read the text and translate it with a dictionary ERNEST RUTHERFORD – ENGLISH PHYSICIST ''That's the last potato I'll ever dig!'' That statement was attributed to young Ernest Rutherford, a native of New Zealand. Rutherford had applied for a scholarship to Cambridge University, one of England's most famous universities. Rutherford had actually finished second in the scholarship competition. But the winner had decided to stay in New Zealand and get married. When Rutherford was told he had won the scholarship, he threw down his potato fork and announced the end of his potato-digging days. Rutherford went on to become one of the great scientific figures of the twentieth century. He made a number of important discoveries about the structure of atoms and about radioactivity. For example, he found that an atom consists of two distinct parts, the nucleus and the electrons. He also discovered one form of radiation given off by radioactive materials: alpha particles. Alpha particles, he found, are simply helium atoms without their electrons. Rutherford was also the first scientist to change one element into another. He accomplished this by bombarding nitrogen gas with alpha particles. Rutherford found that oxygen was formed in this experiment. He had discovered a way to convert one element (nitrogen) into a different element (oxygen). The method Rutherford used later became a standard procedure used by many other scientists. One form of radiation produced by uranium consists of alpha particles. Alpha particles are tiny particles moving at very high rates of speed. In 1907, English physicist Ernest Rutherford (1871-1937) showed that an alpha particle is nothing more than a helium atom without its electrons. As uranium atoms broke apart, then, they gave off alpha particles (helium atoms). That is why helium was first found on Earth in connection with uranium ores. 33


PHYSICAL PROPERTIES Helium is a colorless, odorless, tasteless gas. It has a number of unusual properties. For example, it has the lowest boiling point of any element, -268.9¿C (-452.0¿F). The boiling point for a gas is the temperature at which the gas changes to a liquid. The freezing point of helium is -272.2¿C (-458.0¿F). Helium is the only gas that cannot be made into a solid simply by lowering the temperature. It is also necessary to increase the pressure on the gas in order to make it a solid. At a temperature of about -271¿C (-456¿F), helium undergoes an unusual change. It remains a liquid, but a liquid with strange properties. Superfluidity is one of these properties. The forms of helium are so different that they are given different names. Above 271¿C, liquid helium is called helium I; below that temperature, it is called helium II. Helium is completely inert. It does not form compounds or react with any other element. Occurrence in nature Helium is the second most abundant element after hydrogen in the universe and in the solar system. About 11.3 percent of all atoms in the universe are helium atoms. By comparison, about 88.6 percent of all atoms in the universe are hydrogen. Thus, at least 99.9 percent of all atoms are either hydrogen or helium atoms. By contrast, helium is much less abundant on Earth. It is the sixth most abundant gas in the atmosphere after nitrogen, oxygen, argon, carbon dioxide, and neon. It makes up about 0.000524 percent of the air. It is probably impossible to estimate the amount of helium in the Earth's crust. The gas is produced when uranium and other radioactive elements break down. But it often escapes into the atmosphere almost immediately. ISOTOPES Two isotopes of helium occur naturally, helium-3 and helium-4. Isotopes are two or more forms of an element. Isotopes differ from each other according to their mass number. The number written to the 34


right of the element's name is the mass number. The mass number represents the number of protons plus neutrons in the nucleus of an atom of the element. The number of protons determines the element, but the number of neutrons in the atom of any one element can vary. Each variation is an isotope. Three radioactive isotopes of helium have been made also. A radioactive isotope is one that breaks apart and gives off some form of radiation. Radioactive isotopes are produced when very small particles are fired at atoms. These particles stick (присоединяться, внедряться) in the atoms and make them radioactive. None of the radioactive isotopes of helium has any commercial application.

TEXT 4 Pre-reading tasks 1. Consult a dictionary and read the words. Remember their pronunciation Reservoir, aeronautics, kilogram, leakage, reserve, mixture, dirigible. 2. Words to be remembered superconductivity – сверхпроводимость surface – поверхность inflate – наполнять worthwhile – заслуживающий внимания waste – пустой welding systems – сварочные системы essential – важный, основной leak – протечка flow – поток evaporate – испаряться mixture – смесь 3. Translate the following words into Russian, defining parts of the speech Liquid – liquefy, collect – collecting, gas – gaseous, superconductivity – superconducting, detection – detector, leak – leakage, flame – 35


flammable, cool – cooling, extract – extraction, evaporate – evaporation, discover – discovery. 4. Translate the sentences into Russian 1. If the liquid air were allowed to evaporate, the last gas remaining after all other gases had evaporated would be helium. 2. If a leak is suspected in a long pipe, helium can be used to look for that leak. 3. If they do, they are less likely to join to each other. If the welding is done in a container of helium, this is not a problem. 5. Read the text and translate it with a dictionary EXTRACTION In theory, helium could be collected from liquid air. Liquid air is air that has been cooled to a very low temperature. All of the gases in air have liquefied in liquid air. If the liquid air were allowed to evaporate, the last gas remaining after all other gases had evaporated would be helium. There is too little helium in air to make this process worthwhile, however. There is a much better source of helium. The gas often occurs along with natural gas in reservoirs deep beneath the Earth's surface. When wells are dug to collect the natural gas, helium comes to the surface with the natural gas. Then, helium can be separated from natural gas very easily. The temperature of the mixture is lowered, and the natural gas liquefies and is taken away. Gaseous helium is left behind. About 80 percent of the world's helium is in the United States. In 1996, 20 U.S. plants produced helium from gas wells. About 86 percent of U.S. helium comes from five large underground regions: the Hugoton Field that lies beneath Kansas, Oklahoma, and Texas; the Keyes Field in Oklahoma; the Panhandle and Cliffside Fields in Texas; and the Ridley Ridge area in Wyoming. For many years, the U.S. government operated the Federal Helium Program. This program was responsible for collecting and storing helium for government use. The main customers for this helium were the Department of Defense, the National Aeronautics and Space

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Administration, and the Department of Energy. The helium was stored underground in huge natural caves. In 1996, the government decided to end this program. Helium was no longer regarded as essential to national security. The Bureau of Mines has begun to sell off the federal reserves. USES The most important single use for helium in the United States is in low-temperature cooling systems. This is because liquid helium – at -270¿C – cold enough to cool anything else. For example, it is used in superconducting devices. A superconducting material is one that has no resistance to the flow of electricity. Once an electric current begins to flow in the material, it will continue to flow forever. No energy is wasted in moving electricity from one place to another. Superconducting materials may revolutionize electrical systems worldwide someday. The problem is that superconductivity occurs only at very low temperatures. One way to achieve those temperatures is with liquid helium. Another important use of helium is in pressure and purge systems. In many industrial operations, it is necessary to pressurize a system. The easiest way to do that is to pump a gas into the system. But the gas should not be one that will react with other substances in the system. Being inert, helium is a perfect choice. Helium is also used for purging, a process that sweeps away all gas in a container. Again, helium is used because it does not react with anything in the container. Helium is used to inflate balloons and other lighter-than-air crafts, such as dirigibles (blimps). Because of its inactivity, helium is also used in welding systems. Welding is the process by which two metals are heated to high temperatures in order to join them to each other. Welding rarely works well in "normal" air. At high temperatures, the metals may react with oxygen to form metal oxides. If they do, they are less likely to join to each other. If the welding is done in a container of helium, this is not a problem. The metals will not react with helium. They will simply join to each other. Helium is also used in leak-detection systems. If a leak is suspected in a long pipe, helium can be used to look for that leak. It is pumped into 37


one end of the pipe. A detector is held outside the pipe. The detector is designed to measure whether helium is escaping from the system. The detector is moved along the length of the pipe. It is possible to find out whether there is a leak, where it is, and how much it is leaking. Helium is a good gas to use for this purpose because it does not react with anything in the pipe. Helium is also used to inflate balloons and other lighter than air crafts, such as dirigibles (blimps). Helium does not have the lifting power of hydrogen. However, hydrogen is flammable and helium is not. At one time, people thought that dirigibles would be a popular form of transportation. But that never happened. Blimps are still used for limited purposes, such as advertising at major sports and recreational events. 6. Read the overview and translate it OVERVIEW Rhenium was discovered by a German research team that included Walter Noddack (1893-1960), Ida Tacke (1896-1979) and Otto Berg. These scientists knew that there were two empty boxes in the periodic table that represented elements that had not yet been discovered. The periodic table is a chart that shows how chemical elements are related to one another. In 1925, the German team announced that they had found both elements. They were correct about one (element number 75) but wrong about the other (element number 43). Rhenium is one of the rarest elements in the world. At one time it sold for about $10,000,000 a kilogram (about $5,000,000 a pound). It is no longer that expensive, although it is still very costly. Rhenium has some unusual properties. For example, it is one of the most dense elements known. It also has one of the highest boiling points of all elements.

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TEXT 5 Pre-reading tasks 1. Consult a dictionary and read the words. Remember their pronunciation Chemical, rhenium, thermostat, iron, cubic centimeter, masurium, sulfuric, acid, nitric, mining, molybdenite, gadolinite, columbite, technetium. 2. Words to be remembered mining – добыча полезных ископаемых rhenium – рений ductile –тягучий, дуктильный malleable – плавкий melting point – точка таяния break apart – разрывать stable – стабильный moderately – в малой степени superalloy – суперсплав half life – полураспад brittle – хрупкий sample – образец withstand – противостоять 3. Translate the following sentences, pay attention to the nonfinite forms and modal verbs 1. But they knew that five more were waiting to be discovered. 2. In this case, the German team turned out to be half right. 3. These numbers are among the highest to be found for any of the chemical elements. 4. In this case, the German team turned out to be half right. 5. Its abundance is thought to be about one part per billion. 6. Scientists were able to confirm the existence of element 75. They were not able to confirm the Germans' discovery of element 43. 7. When heated, most metals reach a point where they change from being ductile to being brittle. 8. The unusual behavior of rhenium means that it can be heated and recycled many times without breaking apart. 39


4. Read the text and translate it with a dictionary MASURIUM DISCOVERY AND NAMING At the beginning of the 1920s, chemists knew they were approaching a milestone. They had already isolated 87 chemical elements. But they knew that five more were waiting to be discovered. How did they know? Every element has a space in the periodic table. An empty space meant that an element was missing. In 1920, five empty spaces were still left in the periodic table. Chemists worldwide were searching for these five elements. In 1925, Noddack, Tacke, and Berg reported that they had found two of those elements: numbers 43 and 75. They called the first element masurium, after the region called Masurenland in eastern Germany. They named element number 75 rhenium, after the Rhineland, in western Germany. Rhenium was the last naturally occurring element to be discovered. When a discovery like this is announced, other chemists try to repeat the experiments. They see if they get the same results as those reported. In this case, the German team turned out to be half right. Scientists were able to confirm the existence of element 75. They were not able to confirm the Germans' discovery of element 43. In fact, it was another decade before element 43 (technetium) was actually discovered. PHYSICAL PROPERTIES Rhenium is a ductile, malleable, silvery metal. Ductile means capable of being drawn into thin wires. Malleable means capable of being hammered into thin sheets. It has a density of 21.02 grams per cubic centimeter, a melting point of 3,180多C (5,760多F), and a boiling point of 5,630多C (10,170多F). These numbers are among the highest to be found for any of the chemical elements. Rhenium is quite dense, which is unusual for a metal. When heated, most metals reach a point where they change from being ductile to being brittle. They can be worked with below that point, but not above it. Above this transition temperature they become brittle. If one tries to bend or shape them, they break apart. The unusual behavior of 40


rhenium means that it can be heated and recycled many times without breaking apart. CHEMICAL PROPERTIES Rhenium is a moderately stable metal. It does not react with oxygen and some acids very readily. But it does react with strong acids such as nitric acid (HNO3) and sulfuric acid (H2SO4). Occurrence in nature About a third of all rhenium used in the United States comes from copper and molybdenum ores in the Western states. It is obtained during the process of copper mining. Two-thirds are imported from other countries, primarily Chile, Germany, and the United Kingdom. The principal ores of rhenium are molybdenite, gadolinite, and columbite. Rhenium is one of the rarest elements in the world. Its abundance is thought to be about one part per billion. ISOTOPES Two isotopes of rhenium occur in nature, rhenium-185 and rhenium187. Isotopes are two or more forms of an element. Isotopes differ from each other according to their mass number. The number written to the right of the element's name is the mass number. The mass number represents the number of protons plus neutrons in the nucleus of an atom of the element. The number of protons determines the element, but the number of neutrons in the atom of any one element can vary. Each variation is an isotope. Rhenium-187 is radioactive. A radioactive isotope is one that breaks apart and gives off some form of radiation. The half life of rhenium187 is about 100.000.000 years. The half life of a radioactive element is the time it takes for half of a sample of the element to break down. For example, of a 100-gram sample of rhenium-187, only half that amount, or 50 grams, would be left after 100.000.000 years. The other 50 grams would have broken down and changed into another isotope. Extraction Ores containing rhenium are first roasted, or heated in air, to convert them to rhenium oxide (ReO3). Hydrogen gas is then passed over the 41


rhenium oxide. The hydrogen converts the rhenium oxide to the pure metal. USES About three-quarters of all rhenium consumed in the United States are used in the manufacture of superalloys. A superalloy is an alloy made of iron, cobalt, or nickel. It has special properties, such as the ability to withstand high temperatures and attack by oxygen. Superalloys are widely used in making jet engine parts and gas turbine engines. Alloys containing rhenium also have many other applications. They are used in making devices that control temperatures (like the thermostat in your home), heating elements (like those on an electric stove), vacuum tubes (like those in a television set), electromagnets, electrical contacts, metallic coatings, and thermocouples. A thermocouple is used like a thermometer for measuring very high temperatures. About a quarter of the rhenium consumed in the United States is used as a catalyst in the petroleum industry. A catalyst is a substance used to speed up or slow down a chemical reaction without undergoing any change itself. Rhenium catalysts are used in the reactions by which natural petroleum is broken down into more useful fragments, such as gasoline, heating oil, and diesel oil. Complete studies on the health effects of rhenium are not available. For that reason, it should be assumed to be toxic and be handled with caution. 5. Complete the sentences 1. A thermocouple is used like a thermometer … 2. A catalyst is a substance used … 3. A superalloy is an alloy made of … 4. Rhenium was the last naturally occurring … 5. Ductile means capable of … 6. Isotopes are two or more … 7. The half life of a radioactive element is …

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TEXT 6 Pre-reading tasks 1. Consult a dictionary and read the words. Remember their prononciation Neptunium, atomic, dialuminide, beryllide, 2. Words to be remembered fission – расщепление collide – сталкиваться magnesium – магний compound – сложное вещество splitting – расщепление fairly – ясно hazardous – рискованный spontaneously – спонтанно caution – осторожность 3. Translate the following words into Russian, defining parts of the speech. Collide – collision, produce – production, react – reactor – reaction – reactive, 4. Translate the following sentences into Russian. 1. But a "neutron change" like the ones described above would produce an element with atomic number 93. 2. Of a sample of neptunium-237, only half would remain after 2.140.000 years. The other half would have broken down to form new elements. 3. What elements would a chemist have found on the Earth in those days? 4. If 100 million tonnes of neptunium were present at the Earth's beginning, only 50 million tons would be left after two million years. 5. After another two million years (four million years altogether), only 25 million tons would be left. 6. After another two million years (six million years altogether), only 12.5 million tons would be left.

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5. Read the text and translate it with a dictionary NEPTUNIUM DISCOVERY AND NAMING The discovery of neptunium in 1940 represented an important breakthrough in the study of chemical elements. Scientists had known for nearly a decade about an unusual kind of reaction. When an element is bombarded with neutrons, it sometimes changes into a new element. That new element has an atomic number one, greater than the original element. For example, bombarding copper (atomic number 29) with neutrons may result in the production of zinc (atomic number 30). Bombarding sodium (atomic number 11) with neutrons may result in magnesium (atomic number 12). One reason this discovery fascinated scientists was the possibility of bombarding uranium (atomic number 92) with neutrons. In the 1930s, uranium was the heaviest element known. It was the last element in the periodic table. But a "neutron change" like the ones described above would produce an element with atomic number 93. No one had ever heard of an element with atomic number 93! In 1940, a pair of physicists at the University of California at Berkeley were studying this problem. Edwin M. McMillan (1907-91) and Philip H. Abelson (1913) reported finding evidence of element number 93. They suggested naming it neptunium, in honor of the planet Neptune. (Uranium, the element before neptunium, had been named for the planet Uranus.) PHYSICAL AND CHEMICAL PROPERTIES Neptunium is fairly reactive and forms some interesting compounds. Examples include neptunium dialuminide (NpAL2) and neptunium beryllide (NpBe3). These compounds are unusual because they consist of two metals joined to each other. Normally, two metals do not react with each other very easily. Neptunium also forms a number of more traditional compounds, such as neptunium dioxide (NpO2), neptunium trifluoride (NpF3), and neptunium nitrite (NpNO2). Occurrence in nature

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When neptunium was first discovered, scientists thought it was an entirely artificial, or man-made, element. In 1942, very small amounts of the element were found in the Earth's crust. The element can sometimes be found in ores containing uranium and other radioactive elements. ISOTOPES All isotopes of neptunium are radioactive. Isotopes differ from each other according to their mass number. The number written to the right of the element's name is the mass number. The mass number represents the number of protons plus neutrons in the nucleus of an atom of the element. The number of protons determines the element, but the number of neutrons in the atom of any one element can vary. Each variation is an isotope. A radioactive isotope is one that breaks apart and gives off some form of radiation. Radioactive isotopes are produced when very small particles are fired at atoms. These particles stick in the atoms and make them radioactive. The longest lived isotope is neptunium-237. Its half life is 2.140.000 years. The half life of a radioactive element is the time it takes for half of a sample of the element to break down. Of a sample of neptunium237, only half would remain after 2.140.000 years. The other half would have broken down to form new elements. Neptunium-239 is the only isotope of neptunium to have practical uses. It is used in special instruments for detecting the presence of neutrons. EXTRACTION Pure neptunium metal can be made by heating neptunium trifluoride (NpF3) with hot barium or lithium metal. The metal can now be purchased for Legal uses from the Oak Ridge National Laboratory in Oak Ridge, Tennessee.

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TEXT 7 Pre-reading tasks 1. Consult a dictionary and read the words. Remember their prononciation measure, hazardous, actinide, uranium, alkaline. 2. Words to be remembered measure – мера stable – стабильный penetrate – проникать transfer – переносить cell – клетка tissue – ткань fission – расщепление collision – сталкновение 3. Translate the following sentences 1. Their half lives are 4.6 billion years, 700 million years, and 25 million years. If 100 metric tons of uranium were present when the Earth was formed five billion years ago, about half of the first isotope would have broken down by now. 2. About 50 metric tons of the element would remain. Scientists would have no trouble finding the element in the Earth's crust. 3. No need to do the calculations: Not very much neptunium at all would be left! 4. Scientists would have no trouble finding the element in the Earth's crust. 4. Read the text and translate it with a dictionary THE CASE OF THE DISAPPEARING ELEMENTS Scientists think that the Earth was formed about five billion years ago. What elements would a chemist have found on the Earth in those days? Part of the answer to that question is easy. Most of the elements found today were probably present five billion years ago. Those are the

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stable, or constant, elements. An untouched lump of gold in the Earth's crust five billion years ago would still be a lump of gold today. But that statement is not true for radioactive elements. Radioactive elements "fall apart" spontaneously. They break down and form new, simpler elements. The rate at which radioactive elements break down differs from element to element, however. Some break down slowly, others break down quickly. Scientists measure the rate of breakdown in half lives. An element with a long half life breaks down very slowly. An element with a short half life breaks down quickly. Uranium, for example, has three naturally occurring isotopes. Their half lives are 4.6 billion years, 700 million years, and 25 million years. If 100 metric tons of uranium were present when the Earth was formed five billion years ago, about half of the first isotope would have broken down by now. About 50 metric tons of the element would remain. Scientists would have no trouble finding the element in the Earth's crust. But neptunium is a different story. Its longest lived isotope is neptunium-237, with a half life of about two million years. If 100 million tonnes of neptunium were present at the Earth's beginning, only 50 million tons would be left after two million years. After another two million years (four million years altogether), only 25 million tons would be left. After another two million years (six million years altogether), only 12.5 million tons would be left. Continue the mathematics. How much neptunium is left after 8 million years, 10 millions years, 12 million years, ... 5 billion years? No need to do the calculations: Not very much neptunium at all would be left! Perhaps, too little to even find in the Earth's crust. So what does this example suggest about other transuranium elements, such as plutonium (number 94) and americium (number 95)? All of these elements have fairly short half lives. Of course, "fairly short" sometimes means "only" a few million years! USES AND COMPOUNDS Neptunium and its compounds of neptunium have been made for research purposes. They are used in specialized detection devices and

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in nuclear reactors. Neither the element nor its compounds have any commercial uses. Neptunium is a very hazardous material. It must be handled with great caution. HEALTH EFFECT Neptunium is a very hazardous material. The radiation it gives off can cause serious health problems for humans and animals. It must be handled with great caution. Radiation transfers large amounts of energy to cells and is quite penetrating. Cells that are damaged, but not killed, often reproduce out of control. This growth by functionally damaged cells forms tumors and causes related problems for organs and tissues. 4. Continue the sentences. 1. The mass number represents the number of protons … 2. A radioactive isotope is … 3. The number of protons determines the element, but the number of neutrons in the atom … 4. Scientists measure the rate of breakdown … 5. Radiation transfers large amounts of energy to cells and is … 5. Read the overview and translate it with a dictionary OVERVIEW Neptunium lies in Row 7 of the periodic table. The periodic table is a chart that shows how chemical elements are related to one another. Neptunium is the first transuranium element. The term transuranium means "beyond uranium." Any element with an atomic number greater than 92 (uranium's atomic number) is called a transuranium element. Elements in Row 7 are also called actinide elements. This name comes from the first element in Row 7, actinium. Scientists have now found about 18 isotopes of neptunium. They are all radioactive. Neptunium was once a very rare element, but it can now be somewhat easily produced in a nuclear reactor. A nuclear reactor is a device in which nuclear fission reactions occur. Nuclear 48


fission is the process of splitting atoms when neutrons collide with atoms of uranium or plutonium. These collisions produce new elements. Neptunium is used commercially only in specialized detection devices. TEXT 8 1. Consult a dictionary and read the words. Remember their prononciation. Trimorphic, electrolysis, hydrocarbide, cement, acetylene, hexagonal, rhombohedric 2. Remember the following words. trimorphic – тигидроаксазиновый alkaline – щелочь softener – умягчитель solvay – метод Сольие coating – покрытие corrosion – коррозия, ржавение lead – олово mortar – известковый раствор quenching – охлаждение birrefringent – двоякопреломляющий lime – известь hexagonal – десятигранный tissue – ткань ammonia – аммиак treatment – обращение

3. Translate the following sentences, mind the comparative constructions. 1. The metal is used in aluminium alloys for bearings, as a helper in the bismuth removal form lead, as well as in controlling graphitic carbon in melted iron. 2. As well as beryllium and aluminium, and unlike the alkaline metals, it doesn’t cause skin-burns.

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3. The calcium halogenures include phosphorescent fluoride, which is the calcium compound more abundant and with important applications in spectroscopy. 4. During childhood and adolescence, there’s more production of new tissue than destruction of the old one, but at some point, somewhere around the 30 or 35 years of age, the process is inverted and we start to loose more tissue than what we can replace. 4. Read the text and translate it with a dictionary CALCIUM The chemical element Calcium (Ca), atomic number 20, is the fifth element and the third most abundant metal in the earth’s crust. The metal is trimorphic, harder than sodium, but softer than aluminium. As well as beryllium and aluminium, and unlike the alkaline metals, it doesn’t cause skin-burns. It is less chemically reactive than alkaline metals and than the other alkaline-earth metals. Calcium ions solved in water form deposits in pipes and boilers and when the water is hard, that is, when it contains too much calcium or magnesium. This can be avoided with the water softeners. In the industry, metallic calcium is separated from the melted calcium chloride by electrolysis. This is obtained by treatment of carbonated minerals with chlorhydric acid, or like a sub product of the carbonates Solvay process. In contact with air, calcium develops an oxide and nitride coating, which protects it from further corrosion. It burns in the air at a high temperature to produce nitride. The commercially produced metal reacts easily with water and acids and it produces hydrogen which contains remarkable amounts of ammonia and hydrocarbides as impurities. APPLICATIONS The metal is used in aluminium alloys for bearings, as a helper in the bismuth removal form lead, as well as in controlling graphitic carbon in melted iron. It is also used as a deoxidizer in the manufacture of many steels; as a reducing agent in the preparation of metals as 50


chromium, thorium, zirconium and uranium, and as separating material for gaseous mixtures of nitrogen and argon. Calcium is an alloying used in the production of alluminium, beryllium, copper, lead and magnesium alloys. It is also used in making cements and mortar that are used in builldings. The calcium oxide, CaO, is produced by thermal decomposition of carbonated minerals in furnaces, applying a continuous bed process. The oxide is used in high intensity light arcs (lime light) for its unusual spectral characteristics and as dehydrating industrial agent. The metallurgic industry extensively uses the oxide during the reduction of ferrous alloys. The calcium oxide, Ca(OH)2, has many applications in which the hydroxyl ion is necessary. In the process of calcium hydroxide quenching, the volume of blown out lime [Ca(OH)2] expends to double the initial quantity of quick lime (CaO), fact that makes it useful to break down rocks or wood. The quick lime is an excellent absorbent for the carbon dioxide, because it produces carbonate, which is very insoluble. The calcium silicate, CaSi, prepared in an electric oven from lime, silica and reducing carbonated agents, is useful as a steel-deoxidizing agent. Calcium carbide, CaC2, is produces when heating up a mixture of lime and carbon at 3000ÀC in an electric oven and it is an acetylate which produces acetylene by hydrolysis. The acetylene is the base material of a great number of important chemicals for the organic industrial chemistry. The pure calcium carbonate occurs in two crystalline forms: calcite, hexagonal shaped, which possesses birrefringent properties, and aragonite, rhombohedric. The natural carbonates are the most abundant calcium minerals. The Iceland spar and the calcite are essentially pure carbonate forms, whilst the marble is impure and much more compact, reason why it can be polished. It’s very demanded as construction material. Although the calcium carbonate is very little soluble in water, it is quite soluble if the water contains dissolved carbon dioxide, for in these solutions it forms bicarbonate when dissolving. This fact explains the cave formation, where the lime stone deposits have been in contact with acid waters. The calcium halogenures include phosphorescent fluoride, which is the calcium compound more abundant and with important applications 51


in spectroscopy. The calcium chloride possesses, in the anhydric form, great deliquescence capacity, which makes it useful as industrial dehydrating agent and as sand whirl control factor in roads. Calcium hypochlorite (whitening powder) is produced in the industry when passing chlorine through a lime solution, and has been used as a whitening agent and as water purifier. The dehydrated calcium sulphate is the mineral gypsum, constitutes the bigger portion of Portland concrete, and has been used to reduce the alkalinity of soils. Heating gypsum at high temperatures produces a calcium sulphate hemihydrate, which is sold with the commercial name of Parisian stucco.

TEXT 9 1. Consult a dictionary and read the words. Remember their prononciation. Skeleton, calcium, stalagmite, phosphate, osseous. 2. Words to be remembered kidney – почка skeleton – скелет vertebrate – позвоночник phosphate – фосфат osseous – костный blood vessel – кровеносный сосуд 3. Read the text and translate it with a dictionary CALCIUM IN THE ENVIRONMENT Calcium is the fifth element and the third most abundant metal in the earth’s crust. The calcium compounds account for 3.64% of the earth’s crust. The distribution of calcium is very wide; it is found in almost every terrestrial area in the world. This element is essential for the life of plants and animals, for it is present in the animal’s skeleton, in tooth, in the egg’s shell, in the coral and in many soils. Seawater contains 0.15% of calcium chloride.

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Calcium cannot be found alone in nature. Calcium is found mostly as limestone, gypsum and fluorite. Stalagmites and stalactites contain calcium carbonate. Calcium is always present in every plant, as it is essential for its growth. It is contained in the soft tissue, in fluids within the tissue and in the structure of every animal's skeleton. The vertebrate's bones contain calcium in the form of calcium fluoride, calcium carbonate and calcium phosphate. HEALTH EFFECTS OF CALCIUM Calcium is the most abundand metal in the human body: is the main constituent of bones and theets and it has keys metabolic functions. Calcium is sometimes referred to as lime. It is most commonly found in milk and milk products, but also in vegetables, nuts and beans. It is an essential component for the preservation of the human skeleton and teeth. It also assists the functions of phosphate and muscles. The use of more than 2.5 grams of calcium per day without a medical necessity can lead to the development of kidney stones and sclerosis of kidneys and blood vessels. A lack of calcium is one of the main causes of osteoporosis. Osteoporosis is a disease in which the bones become extremely porous, are subject to fracture, and heal slowly, occurring especially in women following menopause and often leading to curvature of the spine from vertebral collapse. Unlike most of the people think, there is an intense biological activity inside our bones. They are being renewed constantly by new tissue replacing the old one. During childhood and adolescence, there's more production of new tissue than destruction of the old one, but at some point, somewhere around the 30 or 35 years of age, the process is inverted and we start to loose more tissue than what we can replace. In women the process is accelerated after the menopause (he period marked by the natural and permanent cessation of menstruation, occurring usually between the ages of 45 and 55); this is because their bodies stop producing the hormone known as estrogen, one of which functions is to preserve the osseous mass. Evidence suggests that we need a daily intake of 1.000 milligrams of calcium in order to preserve the osseous mass in normal conditions. 53


This is both for man and pre-menopausic women. The recommended daily intake rises to 1.500 for menopausic woman. The main calcium sources are the dairy products, but also nuts, some green vegetables like spinach, and cauliflower, beans, lentils (чечевица)… Calcium works together with magnesium to create new osseous mass. Calcium should be taken together with magnesium in a 2:1 rate, that is to say, if you ingest 1000 mg of calcium, you should also ingest 500 mg of magnesium. Some magnesium sources in the diet are seafood (морепродукты), whole-grains (цельные зерна), nuts, beans, wheat oats, seeds and green vegetables. Other important measures to prevent osteoporosis are: Doing regular exercise (at least three times a week) Taking adequate amounts of manganese (марганец), folic acid (фолиевая кислота), vitamin B6, vitamin B12, omega 3 (it aids calcium absorption and stimulates new osseous mass production) and vitamin D (it aids calcium absorption in the small intestine). Not abusing of sugar, saturated grease and animal proteins Not abusing (употребление) of alcohol, caffeine, nor gaseous drinks Not smoking Other triggers for osteoporosis are the hereditary (наследственный) factor and the stress. 4. Find information about Environmental effects of calcium and make a presentation.

TEXT 10 1. Read the text and translate it with a dictionary INTERACTION OF NITROGEN OXIDES WITH POLYMERS The reactions with nitrogen oxides present in the atmosphere is an important factor contributing to the deterioration of the polymer properties during ageing. The review is devoted to the mechanism of reactions of nitrogen oxides with various types of polymers. 54


The reactions of reactive polymer groups with gases diffusing in the polymer bulk are distributed non-uniformly throughout the bulk; this hampers the kinetic description of these processes. In addition, reaction kinetics depends on the rate of relaxation processes in the polymer. Data on ageing of polymers of various classes obtained by conventional methods are presented in the review together with the EPR studies of the processes in question. Reactions of nitrogen oxides with various types of polymers are described in detail. Polymers containing no double bonds are not very sensitive to nitrogen oxides. Rubbers are much more sensitive to these agents (nitrogen oxides can either detach allylic hydrogen atoms or add to the double bonds). The kinetics and mechanisms of reactions of double bonds in polymers with nitrogen oxides are considered comprehensively. In addition to double bonds, amide groups of macromolecules, tluorinated groups, hydroperoxides and peroxide macroradicals are active participants of the reactions with nitrogen oxides. The oxide reacting predominantly with amide groups is NaO4. The cross-linking and destruction processes occurring in parallel are discussed. It is shown that at high temperatures, NO can disproportionate to give Na and active NO3 radical. This stage may be responsible for the selfacceleration of hydroperoxide decomposition in an atmosphere of nitrogen oxides. Particular emphasis is given to the mechanism of the formation of nitrogen-containing radicals. The known structures of stable nitrogencontaining macroradicals formed allow one to draw conclusions concerning the free-radical stages of ageing. The simple methods of synthesis of spin-labeled macromolecules based on free-radical reactions with nitrogen oxides have been considered. These methods are of great importance in the case of insoluble and chemically inert polymers such as polyperfluoroolefins. For PTFE and in the copolymer of tetrafluoroethylene with hexafiuoropropylene, the macromolecules containing paramagnetic nitroxide groups both in the middle and at the end of the polymer chain, were prepared in this way. The produced nitroxide radicals made it possible to investigate the structure and the reaction-front movement during nitration of solid polymers by means of ESR imaging technique. 55


5. Make an overview to the text

TEXT 11 1. Read the text and translate it with a dictionary MECHANOCHEMICAL SYNTHESIS OF INTERMETALLIC COMPOUNDS In recent decades, the mechanochemical method has been often used to prepare intermetallic compounds. The review presents the current state of research in the field of mechanochemical synthesis in metallic systems with both negative and positive enthalpies of mixing. It is demonstrated that this method of synthesis of intermetallic compounds and solid solutions can be performed for many pairs of metals. Numerous examples are given. In practice, the method is especially significant when the components have very high melting points (synthesis of MoSi2), when the difference between the melting points and densities of the components is great (MgTi); in those cases where the temperatures of the conventional synthesis are too high; and also when phases with a nanometer grain size are required. This method is also used for the pretreatment of components prior to thermal synthesis. The mechanochemical approach is the most promising for the synthesis of metastable phases, supersaturated solid solutions and amorphous phases. The most pronounced extension of the concentration regions of supersaturated solid solutions is attained in those systems in which components have similar atomic radii and can undergo phase transitions to related structural types. A specific feature of materials obtained by the mechanochemical route is high dispersity (in most cases, they include nano-sized particles), which permits one to influence substantially their physicochemical properties. The main factors influencing the concentration boundaries of the nonequilibrium solid solutions prepared by mechanochemical method are elucidated. 56


Structural transformations occurring in the material during treatment in a mill are analysed. As a result of high plastic deformation, the components react to give either equilibrium or non-equilibrium chemical compounds (intermetallic compounds and solid solutions). The mechanisms of the processes are discussed in detail. Several hypotheses are stated and analysed. It is demonstrated for numerous examples that the process of formation of solid solutions can be represented by several stages including the formation components to nanometer sizes (i.e. the formation of a large contact area of the components); synthesis of intermetallic compounds in nano-sized layered composites; dissolution of the resulting intermetallic compounds in the solvent metal to give a solid solution. 2. Make an overview to the text

TEXT 12 1. Read the text and translate it with a dictionary SILICON IS THE ELEMENT OF THE 21st CENTURY Discussions on the main results of the work on the Project were on the agenda of the Second Conference on Material Studies and Physicochemical Basics of Technologies of Production of Alloyed Silicon Crystals. The conference, which met in Moscow early this year, was attended by scientists from Moscow and the Moscow Region, St. Petersburg, Nizhni Novgorod, Novosibirsk, Krasnoyarsk, Irkutsk, Kiev and Minsk – a total of more than 120 participants. Speakers at the conference stressed that so far only four countries – the United States, Japan, Germany and Russia – have mastered the technologies for polysilicon production although the demand for it is steadily growing. This stems from the needs of such branches as microelectronics and solar power generation which will provide a tangible contribution to electricity generation in the 21 st century. The development of technologies of manufacture of silicon monocrystals is oriented at producing ingots of larger size with mounting demands for getting more perfect crystalline structures and 57


greater uniformity in the distribution of electrophysical properties throughout the volume of the material. The most serious problem encountered in this connection is the need to reduce the size of microflaws which have the strongest impact on the performance characteristics of integrated circuits. Speakers at the conference discussed the results of studies (Institute of Semiconductor Physics) of new types of what are called extension defects in silicon crystals and also the method of modelling of processes of heat and mass transfer, crystallization and defect formation (Institute of Heat Physics) which help reduce the numbers of surface submicronic defects. Polished silicon plates have been mainly used so far for the production of integrated circuits. But with the current transition to submicronic and nanometer levels preference is being given to what are called epitaxial* structures nanometer levels preference is being given to what are called epitaxial* structures especially in view of the prospects of using them for super-fast circuits of the future. Today epitaxial processes (chiefly molecular-ray ones), combined with ionic implantation* and pulsed radiation processing of materials are becoming increasingly important for the formation of silicon structures. There has been growing interest among experts in recent time towards what are called microcrystalline and amorphous silicon films upon glass and metal base. These can be used as solar panels, fine-film transistors for liquid-crystal displays, light emitters and photocells. What is more, methods have been developed of producing such films with preset characteristics. One of the most effective of these consists in using a supersonic gas jet with gas activation by an electron beam. And the rate of precipitation of silicon layers by this technique has turned out to be the greatest. The attention of experts has also been attracted by yet one more modification of this remarkable material – porous silicon. When some of the associated problems (ensuring stability and reproducibility) are resolved the new material will have a future as light emitter in the visible band. So far, however, there have been even more successful studies into what experts call controlled formation of pores massif of preset, configuration in the process of deep photoanodic etching, or scouring of silicon. This kind of structures can be used for the making

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of matrixes of parabolic short-focus X-ray lenses and of components of three-dimensional photon crystals. Another direction of studies of this porous material is linked with the production of unique bases for homo- and heteroepitaxy with the subsequent development on this basis of semiconductors on dielectrics with the help of which it should be possible to reduce pppreciably the parasitic electric effects, ensure reliable insulation of the base layer and achieve a reduction of working voltage and power levels. The smaller are the topological dimensions of the elements in electronic circuits, the greater is their density and the more complex is the architecture of traditional wiring circuits. The latter fact is a tangible obstacle to increasing the rates of response of various instruments. An attractive alternative, therefore, is offered by fiber optics systems which can take care in principle of generation, modulation, amplification, transmission and detection of light signals. But the problem of fiber optics runs into a "snag" of developing an effective radiation reasons. As proved by experience - the problem can be resolved by the introduction of erbium which forms effective centers of emission recombination. In that case the generated emission of 1.54 Mkm is practically not absorbed by silicon and matches the maximum transparency "window" of optical waveguides of quartz glass. The main snag, however, is the low solubility of erbium in silicon. As proved by Siberian researchers, however, this obstacle can be overcome by using what are called non-equilibrium methods of generation of strongly alloyed layers resorting to ionic implantation, molecular-ray epitaxy and ionic-ray spray-coating. Summing it up, in the process of implementation of the above integration project it has been possible to obtain within relatively short time high-quality silicon monocrystals and a range of products on this basis. This opens up new prospects for applied research in the centers of the Siberian Branch of the Russian Academy of Sciences and at the local industrial plants. The aim of it all is obtaining high-tech equipment on the basis of semiconductor silicon. * Epitaxy – oriented growth of a monocrystal on the surface of another. * Ionic implantation – introduction of foreign atoms into a solid body by means of ionic bombardment. 2. Make an overview to the text. 59

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