Nanoengineering. Учебное пособие

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5.We did not mind them scheduling the chess tournament for November.

6.Everybody insisted on this experiment being made once more.

3.State the forms and functions of the gerund. Find gerundial complexes. Translate the sentences into Russian.

1.Skiing is my favourite sport.

2.I remember his telling me about his coat.

3.I remember having seen this match.

4.Before taking up swimming she had been very fond of playing basketball.

5.The football player was punished for having pushed the centre for-

ward.

6.The young high jumper was very proud of being praised.

7.I did not know you had stopped rooting for our team.

8.I remember having been told about this match.

9.Seeing is believing.

10.In copying this text he made a few mistakes.

11.After finishing the experiment the discussed the results.

12.After having read the letter, she put it into her bag.

13.We enrich our knowledge by reading books.

14.Asking him about it was useless.

15.It is good fishing in troubled water.

16.There is nothing doing.

17.Her greatest pleasure is reading such books.

18.He began reading this book yesterday.

19.We insisted on the meeting being put off.

20.I don’t like his manner of reading.

21.I had the pleasure of knowing him personally.

4. Complete the proverbs and sayings by adding gerunds. Employ the suitable gerunds in brackets.

1.Learn to swim by ...

2.Think twice before ...

3.Doing is better than ...

4.Seeing is ...

5.Appetite comes with ...

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6.You can’t make an omelet without ...

7.A watched pot is long in ...

8.Clean hands want no ...

9.It is no use …

10 He who likes borrowing dislikes ...

(speaking; swimming; believing; saying; eating; boiling; paying; washing; crying over the split milk; breaking eggs)

Speaking

5. Give a summary of the text.

UNIT 3. NANOENGINEERING IN FUEL CELLS

Before you read

1. Read and learn the following words and word combinations.

fuel cell – топливный элемент lattice – решетка

handheld device – портативное устройство absorb – поглощать

cap – покрывать

porous silica – пористый кварц nanopore – нанопора

humidity – влажность

bonding energy – энергия связи catalyst – катализатор

2. Read the text and say what new facts you have found. Nanoengineering in Fuel Cells

Catalysts are used with fuels such as hydrogen or methanol to produce hydrogen ions. Platinum, which is very expensive, is the catalyst typically used in this process.

Fuel cells contain membranes that allow hydrogen ions to pass through the cell but do not allow other atoms or ions, such as oxygen, to pass through. Small fuel cells are being developed that can be used to replace batteries in handheld devices such as PDAs or laptop computers. Most com-

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panies working on this type of fuel cell are using methanol as a fuel and are calling them DMFCs, which stands for direct methanol fuel cell. DMFCs are designed to last longer than conventional batteries. Fuel cells that can replace batteries in electric cars are also under development.

It is necessary to develop a lightweight and safe hydrogen fuel tank to hold the fuel and build a network of refueling stations. To build these tanks, researchers are trying to develop lightweight nanomaterials that will absorb the hydrogen and only release it when needed.

Researchers at the University of Illinois have developed a proton exchange membrane using a silicon layer with pores of about 5 nanometers in diameter capped by a layer of porous silica. The silica layer is designed to insure that water stays in the nanopores. The water combines with the acid molecules along the wall of the nanopores to form an acidic solution, providing an easy pathway for hydrogen ions through the membrane. Evaluation of this membrane showed it to have much better conductivity of hydrogen ions (100 times better conductivity was reported) in low humidity conditions than the membrane normally used in fuel cells.

Researchers at Rensselaer Polytechnic Institute have investigated the storage of hydrogen in graphene (single atom thick carbon sheets). Hydrogen has a high bonding energy to carbon, and the researchers used annealing and plasma treatment to increase this bonding energy. High hydrogen to carbon bonding energy and high surface area exposure of carbon gives graphene a good chance of storing hydrogen. The researchers found that they could store 14% by weight of hydrogen in graphene.

Researchers at the SLAC National Accelerator Laboratory have developed a way to use less platinum for the cathode in a fuel cell, which could significantly reduce the cost of fuel cells. They alloyed platinum with copper and then removed the copper from the surface of the film, which caused the platinum atoms to move closer to each other (reducing the lattice space). It turns out that platinum with reduced lattice spacing is a more effective catalyst for breaking up oxygen molecules into oxygen ion. The difference is that the reduced spacing changes the electronic structure of the platinum atoms so that the separated oxygen ions more easily released, and allowed to react with the hydrogen ions passing through the proton exchange membrane.

Another way to reduce the use of platinum for catalyst in fuel cell cathodes is being developed by researchers at Brown University. In laboratory scale testing they found that a catalyst made with spherical nanoparticles of

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palladium generated 12 times more current than a catalyst using pure platinum, and lasted ten times longer. The researchers believe that the improvement is due to a more efficient transfer of electrons than in standard catalysts.

Comprehension

3. Check your understanding of the text answering the following questions.

1.What kinds of catalysts are used to produce hydrogen ions?

2.Is platinum cheap?

3.What allows hydrogen ions to pass through the cell?

4.What are DMFCs? What is their difference from the conventional batteries?

5.What is also necessary to develop in addition to improvements of catalysts and membranes?

6.Why are researchers trying to develop lightweight nanomaterials?

7.What have researchers at university of Illinois developed?

8.What have researchers at Rensselaer Polytechnic Institute investigated?

9.How could researchers at the SLAC National Accelerator Laboratory have developed a way to use less platinum for the cathode in a fuel cell?

10.What is being developed by researchers at Brown University?

Vocabulary development

4. Translate the following words.

catalyst, fuel, expensive, entirely, to create, efficient, to recharge to insert, to propose, improvement, to absorb, to release, pathway, evaluation, conductivity, humidity, to investigate, significantly, copper, film, lattice, separated, to deposit, pure

5. Find the English equivalents in the text.

проникнуть в, переносные (портативные) устройства, обыкновенные батарейки, гарантировать, находиться в стадии разработки; топливный бак; авторазливочная станция; наиболее действенный катализатор распада, обеспечить легкий путь; иметь лучшую проводимость; связующая энергия; значительно сократить; делать сплав платины и меди; поверхность пленки; период решетки (пространственная решетка); длиться; благодаря (вследствие).

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6. Translate into Russian. Pay attention to the prefix re-.

replace, recharge, remove, reuse, rearrange, relocate, rebuild, remake.

Word Building

7. Give derivatives from the following words and translate them.

Example: to use – user – useful – usefulness – useless

to create, to build, to design, to research, to propose, to discuss, to estimate, to occur, to insure, to combine, to evaluate, to conduct, to investigate, to treat, to move, to differ

8. Form adverbs from the following adjectives and translate them.

typical, efficient, direct, conventional, simple, safe, approximate, easy, normal, high, close, effective.

Grammar focus

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9.Find Complex Object Infinitive in the following sentences and translate them.

1.Scientists know this superlattice to possess very interesting electrical properties.

2.David Tomanek, a professor of physics at Michigan State University, considers each of the nanotube forms to find applications for which they are best suited.

3.Since their discovery in 1991, researchers believed carbon nanotubes to be the most important candidates to dominate the 21st century revolution.

4.They assumed the extraordinary magnetoresistance (EMR) effect to work by changing the paths of electrons travelling through the device.

5.Manufacturers of optoelectronics device expected scientists to obtain considerably greater magnetoresistance (MR) from a nonmagnetic metal such as gold.

6.We supposed them to be studying the properties of microelectronic structure called a semiconductor superlattice.

7.The researchers believed magnetoresistance to be the phenomenon in which the electrical resistance of a metal or a semiconductor increases or decreases in response to magnetic field.

8.The design of the nanobattery enables it to lie inactive for at least 15 years, but then it is capable of waking up and immediately providing a burst of high energy.

9.Not only does nanotechnology enable structures to be made much smaller. It also enables effects that are not visible on larger structures to be utilised. Researchers found the material to exhibit different electromagnetic or optical properties on these scales as a result of atomic sizes involved. This opens tremendous opportunities to be exploited in many different ways.

Speaking

10. Find more information about the latest investigations in the field of fuel cells and present it to the groupmates.

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UNIT 4. NANOMECHANICS

Before you read

1.nanomechanics – наномеханика

2.branch – филиал, отрасль

3.elastic – упругий

6.nanometer scale – нанометровый масштаб

7.on the cross-road – на перекрестке

8.the dispersion – рассеивание

9.nanopowders – нанопорошки

10.nanoribbons – наноленты

11.boron – бор

12.nanoshells – нанооболочки

13.nanomebranes – наномембраны

14.nanocoatings – нанопокрытия

15.nanofluids – наножидкости

16.nanotribology – нанотрибология

17.friction – трение

18.wear – износ

19.contact mechanics at the nanoscale – контактная механика на на-

ноуровне

20.discreteness of the subject – дискретность объекта

21.рlurality – множественность

22.finiteness – конечность

23.melting point – температура плавления

3. Match English words and their Russian equivalents.

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4. Read the text and say what BNT, CNT, NEMS stand for. Nanomechanics

1.Nanomechanics is a branch of nanoscience studying fundamental mechanical (elastic, thermal and kinetic) properties of physical systems at the nanometer scale. Nanomechanics has emerged on the cross-road of classical mechanics, solid-state physics, statistical mechanics, materials science, and quantum chemistry. As an area of nanoscience, nanomechanics provides a scientific foundation of nanotechnology. Often, nanomechanics is viewed as a branch of nanotechnology, i.e., an applied area with a focus on the mechanical properties of engineered nanostructures and nanosystems (systems with nanoscale components of importance). Examples of the latter include nanoparticles, nanopowders, nanowires, nanorods, nanoribbons, nanotubes, including carbon nanotubes (CNT) and boron nanotubes (BNT); nanoshells, nanomebranes, nanocoatings, nanocomposite/nanostructured materials, nanofluids (fluids with dispersed nanoparticles); nanomotors, etc.

2.Some of the well-established fields of nanomechanics are: nanomaterials, nanotribology (friction, wear and contact mechanics at the nanoscale), nanoelectromechanical systems (NEMS), and nanofluidics.

3.As a fundamental science, nanomechanics is based on some empirical principles (basic observations), arising from the smallness of physical sizes of the subject of study or research. Examples include:

Discreteness of the subject (subject size becomes comparable with the interatomic lengths)

Plurality, though finiteness, of degrees of freedom in the subject

Rise of thermal fluctuations

Rise of configuration entropy

Rise of quantum effects.

4. These principles serve to provides a basic insight into novel mechanical properties of nanometer objects. Novelty is understood in the sense that

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these properties are not present in similar macroscale objects or much different from the properties of those (e.g., nanorods vs. usual macroscopic beam structures). In particular, smallness of the subject itself gives rise to various surface effects determined by higher surface-to-volume ratio of nanostructures, and thus affects mechanoenergetic and thermal properties (melting point, heat capacitance, etc.) of nanostructures. Discreteness serves a fundamental reason, for instance, for the dispersion of mechanical waves in solids, and some special behavior of basic elastomechanics solutions at small scales. Plurality of degrees of freedom and the rise of thermal fluctuations are the reasons for thermal tunneling of nanoparticles through potential barriers, as well as for the cross-diffusion of liquids and solids. Smallness and thermal fluctuations provide the basic reasons of the Brownian motion of nanoparticles. Increased importance of thermal fluctuations and configuration entropy at the nanoscale give rise to superelasticity, entropic elasticity, and other exotic types of elasticity of nanostructures. Aspects of configuration entropy are also of great interest in the context self-organization and cooperative behavior of open nanosystems. Quantum effects determine forces of interaction between individual atoms in physical objects, which are introduced in nanomechanics by means of some averaged mathematical models called interatomic potentials.

5. Quantum effects also determine novel electrical, optical and chemical properties of nanostructures, and therefore they find even greater attention in adjacent areas of nanoscience and nanotechnology, such as nanoelectronics, advanced energy systems, and nanobiotechnology.

Comprehension check

5. Decide whether these statements are true or false. Correct false ones.

1.As an area of nanoscience, nanomechanics provides a scientific foundation of nanotechnology.

2.Often, nanomechanics is viewed as a branch of nanotechnology.

3.Examples of the latter does not include nanoparticles, nanopowders, nanowires, nanorods, nanoribbons, nanotubes.

4.Some of the well-established fields of nanomechanics are: nanomaterials, nanotribology, nanoelectromechanical systems, and nanofluidics.

5.Increased importance of thermal fluctuations and configuration entropy at the nanoscale give rise to superelasticity, entropic elasticity.

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