- •Шомахова т.Х.
- •Кумыкова Элина Тугановна, Безрокова Мадина Борисовна, Бориева Мархаба Курманбаевна, Абрегова Алла Владимировна
- •Unit I science and society
- •1. Listen to or look through the following text and say what ideas it contains.
- •2. Look through the text again and entitle it.
- •3. Look through the text once more and say what kind of passage it is:
- •4. Read the text thoroughly with a dictionary and answer the following questions:
- •5. Give Russian equivalents to the following words, word combinations and scientific terms from the text:
- •6. Complete the following sentences choosing the words, word combinations or scientific terms from the list below.
- •7. Find synonyms to the given words, word combinations and scientific terms in ex. 5;
- •8. Translate the following sentences into Russian paying attention to the italicized words:
- •1. Read the next text connected with science and give answers to the following questions:
- •How would you answer the questions?
- •Unit II … as a branch of science
- •1. Look through the text concentrating on the beginning and the end of each paragraph, and write an outline, either in Russian or in English (time limit — 10 min.).
- •2. Paragraph Study.
- •3. Read the whole text again and see if any corrections should be made in your original outline.
- •4. Write an abstract of the text in three sentences.
- •Read and translate the text.
- •Unit III modern achievements in electronics and nanoelectronics text 1 Graphene
- •Read and translate the text.
- •Text 2 Molecular scale electronics
- •Read and translate the text.
- •Unit IV outstanding scientists in nanotechnology text 1 Richard Phillips Feynman
- •Read and translate the text.
- •Text 2 Walter Schottky
- •Read and translate the text.
- •Unit V ethical problems of scientific research text 1 The cloning of humans is justifiable
- •Read and translate the text.
- •2. Answer the questions on the text.
- •3. Analyzing the content of a text
- •Text 2 Artificial Intelligence
- •Read the text 'Artificial Intelligence' and say if machines can be as clever as humans.
- •Complete each sentence (a—h) with one of the endings (1-8):
- •Give the definitions of the following words
- •Answer the questions:
- •Fill in the table
- •Read the quotations below. Choose any statement and comment on it
- •1) Read the text and be ready for a comprehension check-up.
- •2) Check up for comprehension.
- •Unit VI special texts text 1 Nanocomposites and their Applications
- •A survey of the applications of nanocomposites. The following survey of nanocomposite applications introduces you to many of the uses being explored, including:
- •Text 2 Synthesis of Nanomaterials by High Energy Ball Milling
- •Unit VII special texts text 1 Synthesis of Nanomaterials by Laser Ablation
- •Text 2 Chemical Vapor Synthesis of Nanomaterials
- •Unit VIII special texts text 1 Nanoelectromechanical system
- •Text 2 Nanocircuitry
- •Unit IX special texts text 1 Carbon nanotube
- •Text 2 Quantum computer
- •Unit X first steps in science
- •Look through the text and be ready to summarize its main ideas.
- •Read the text to find the answers to the following questions:
- •Read the text again to find the answers to the following questions:
- •Speaking
- •Answer the questions:
- •Complete the sentences which contain the words from the Active Vocabulary Section. Speak about your research problem.
- •Answer the questions:
- •Complete the sentences with the words from the Active Vocabulary Section. Speak about the historical background of your research problem.
- •Ask for and give information on the historical background of the research problems under study.
- •Act out the situation.
- •Complete the sentences with the words from the Active Vocabulary Section. Speak about the purpose of your current research and the method used.
- •Ask for and give information about your current research, namely its purpose and the methods you employ.
- •Act out the situation.
- •Answer the questions:
- •Complete the sentences which contain the words from the Active Vocabulary Section. Speak about your research results and conclusions.
- •Ask for and give information about your research results and conclusions.
- •Act out the situations.
- •List of materials used
Text 2 Chemical Vapor Synthesis of Nanomaterials
In this approach, vapor phase precursors are brought into a hot-wall reactor under conditions that favor nucleation of particles in the vapor phase rather than deposition of a film on the wall. It is called chemical vapor synthesis or chemical vapor condensation in analogy to the chemical vapor deposition (CVD) processes used to deposit thin solid films on surfaces.
This method has tremendous flexibility in producing a wide range of materials and can take advantage of the huge database of precursor chemistries that have been developed for CVD processes. The precursors can be solid, liquid or gas at ambient conditions, but are delivered to the reactor as a vapor (from a bubbler or sublimation source, as necessary).
When a mixture of gas reactants are delivered into a reaction chamber, the chemical reactions among the gas molecules are induced by an input of energy such as resistant heating, laser, and plasma. Chlorides are popular reactants for the formation of oxides because of their generally low vaporization temperature and low cost . The typical reaction is as following:
SnCl4 (gas) + 2H2O (gas) → SnO2 (solid) + 4HCl (gas) (1)
Another key feature of chemical vapor synthesis is that it allows formation of doped or multi-component nanoparticles by use of multiple precursors. Schmechel et al. prepared nanocrystalline europium doped yttria (Y2O3:Eu3+)from organometallic yttrium and europium precursors.
Senter et al. incorporated erbium into silicon nanoparticles using disilane and an organometallic erbium compound as precursors. Srdic et al. prepared zirconia particles doped with alumina. Brehm et al. synthesized nanoparticles of indium oxide, tin oxide, and indium oxide doped with tin oxide (ITO) by chemical vapor synthesis for the applications as transparent conducting oxides, catalysts and gas sensors. The powders exhibit a narrow size distribution with an average size of about 5 nm.
Recently, Wang’s group successfully synthesized a series of binary semiconducting oxide nanobelts (or nanoribbons), such as ZnO, In2O3, Ga2 O3, CdO and PbO2 and SnO2 by simply evaporating the source compound. Condensed or powder source material is vaporized in a tube furnace at an elevated temperature and the resultant vapor phase condense under certain conditions (temperature, pressure, substrate, etc.) to form the desired product.
The assynthesized oxide nanobelts are pure, structurally uniform, single crystalline and most of them free from defects and dislocations; they have a rectangular-like cross-section with typical widths of 30 to 300 nanometers, width-to-thickness ratios of 5 to 10, and lengths of up to a few millimeters. The belt-like morphology appears to be a unique and common structural characteristic for the family of semiconducting oxides with cations of different valence states and materials of distinct crystallographic structures.
The nanobelts are an ideal system for fully understanding dimensionally confined transport phenomena in functional oxides and building functional devices along individual nanobelts. Wang’s group has recently applied the nanobelt materials to make the world’s first field effect transistor and single wire sensors.
The latest breakthrough of Wang’s group is the success of first piezoelectric nanobelts and nanorings for applications as sensors, transducers and actuators in micro and nano-electromechanical systems. A typical SEM image of as-synthesized ZnO nanorings is shown in the following figure. Owing to the positive and negative ionic charges on the zinc- and oxygen-terminated ZnO basal planes, respectively, a spontaneous polarization normal to the nanobelt surface is induced. As a result, helical nanosprings/nanocoils are formed by rolling up single crystalline nanobelts. The mechanism for the helical growth is suggested for the first time to be a consequence of minimizing the total energy contributed by spontaneous polarization and elasticity. The nanobelts have widths of 10–60 nanometers and thickness of 5–20 nanometers, and they are free of dislocations. The polar surface dominated ZnO nanobelts and helical nanosprings are likely to be an ideal system for understanding piezoelectricity and polarization induced ferroelectricity at nano-scale.
TASKS
1. Read the title of the passage to know what it deals with.
2. Read the passage carefully to know its content in more detail.
3. Name the paragraphs dealing with the application of the nanobelt materials.
4. Name the paragraphs that describe a rectangular-like cross-section.
5. Find the conclusive paragraph about the mechanism for the helical growth.
6. Find the paragraph concerned with the latest breakthrough of Wang’s group.
7. Thoroughly read paragraph 1 and define its main point. Summarize paragraph 1 in no more than two sentences. Begin with: The paper reports on ...
8. Thoroughly read paragraphs 2, 3, 4 and condense their content. Compress paragraphs 2, 3 and 4 into a statement using the phrases: A careful account is given to... It is reported that... The paper claims that...
9. Thoroughly read paragraphs 5, 6 and condense their content. Compress paragraphs 5 and 6 into a statement using the phrases: Much attention is given to ... It is claimed that... The paper points out that...
10. Summarize the content of the passage using the phrases: The paper provides information on ... The paper defines the phenomenon of... An attempt is made to... The paper points out... The paper claims that...