Nanoengineering. Учебное пособие

6.Quantum effects not determined forces of interaction between individual atoms in physical objects.

7.Quantum effects not determined novel electrical, optical and chemical properties of nanostructures.

6. Select the correct answer.

1.Which word in paragraph 1 means "features".

2.Which word in paragraph 1 means "field".

3.Which word in paragraph 2 means "area".

4.Which word in paragraph 3 means "basis".

5.Which word in paragraph 4 means "to supply".

6.Which word in paragraph 4 means "small size".

7.Which word in paragraph 4 means "hot".

8.Which word in paragraph 5 means "impacts".

9.Which word in paragraph 5 means "power".

Vocabulary development

7. Complete the sentences by giving English equivalents to the Russian words/phrases.

1.(Наномеханика) studies fundamental mechanical (упругий, тепловой, кинетический) properties of physical systems at the nanometer scale.

2.Also nanomechanics is considered as an applied area with a focus on the mechanical properties of engineered (наноструктур и наносистем).

3.Some of the well-established fields of nanomechanics are: nanomaterials, (нанотрибология), nanoelectromechanical systems, and (нано-

жидкости).

4.Empirical principles of nanomechanicsare: discreteness of the subject, (множественность, повышение тепловых флуктуаций),rise of configuration entropy (и квантовых эффектов).

8. Start the sentences:

1. ....... properties of physical systems at the nanometer scale.

2. ....... arising from the smallness of physical sizes of the subject of study or research.

3. ....... into novel mechanical properties of nanometer objects.

4. ....... by higher surface-to-volume ratio of nanostructures, and thus affects mechanoenergetic and thermal properties (melting point, heat capacitance, etc.) of nanostructures.

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open nanosystems.

10. Choose the correct Russian equivalent of the English word.

Grammar focus

Complex Subject

Noun/Pronoun + Predicate + Infinitive

He is said to be a good teacher.

The boy is known to have passed his exams well.

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11. Point out Complex Subject Infinitive constructions in the following sentences and translate them accordingly.

1.Nanophysics is known to deal with physical effects at the nanometer and sub-nanometer scale.

2.Semiconductor superlattice is known to consist of layers stacked like a sandwich.

3.Sensors based on nanotechnology are likely to revolutionize health care, climate control and detection of toxic substances.

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4.Magnetoresistance proved to be the phenomenon in which the electrical resistance of a metal or a semiconductor increases or decreases in response to a magnetic field.

5.A knowledge of processes related to the nanoscale structures is likely to be helpful in developing technologies for preventing or minimizing harm to the environment.

6.Metallic and semiconducting properties of nanotubes are reported to have been constructed by a special method.

7.Research focused on one phenomenon happened to result in the unexpected discovery.

8.Nanostructured systems are considered to constitute a bridge between single molecules and infinite bulk systems.

9.Dozens of research teams across the globe are now assumed to be working to develop robust nanoscale electrical switches based on atoms or molecules.

10Size equations proved to constitute scaling laws for the nuclear electronic level structures and dynamics.

11.In the case considered, each nanowire happened to have several broken connections to the conventional wires.

12.The field of nanoscale fabrication is said to be extremely active today, with many competing techniques being under study.

Speaking

12.Scan the text and note down the essential information. Sum up the main points of the text.

13.Explain the concepts “nanometer scale”, “solid-state physics”, “nanosystems”, “elastomechanics” in your own words the way you understand them.

UNIT 5. NANOMATERIALS

Before you read

1. Answer the questions in pairs or small groups.

1.What is a semiconductor?

2.Where are semiconductors used?

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3.What semiconductor materials do you know?

4.What do you know about semiconductor properties?

2. Read the text and say what semiconductor materials are mentioned in the text.

Semiconductor nanomaterials

Semiconductors are crystalline or amorphous solids with distinct electrical characteristics, but liquid semiconductors are also known. A large number of elements and compounds have semiconducting properties, including certain pure elements (e.g. silicon and germanium), binary compounds (e.g. silicon carbide), certain ternary compounds, oxides, alloys and organic semiconductors made of organic compounds.

When the size of semiconductor materials is reduced to nanoscale, their physical and chemical properties change drastically, resulting in unique properties due to their large surface area or quantum size effect.

Recently there has been substantial interest in the preparation, characterization and application of semiconductor nanoparticles that play a major role in several new technologies. When the size of semiconductor materials is reduced to nanoscale, their physical and chemical properties change drastically, resulting in unique properties due to their large surface area or quantum size effect. The conductivity of the semiconductor and its optical properties (absorption coefficient and refractive index) can be altered. Semiconductor nanomaterials and devices are still in the research stage, but they are promising for applications in many fields, such as solar cells, nanoscale electronic devices, light-emitting diodes, laser technology, waveguide, chemical and biosensors, packaging films, superabsorbents, components of armor, parts of automobiles, and catalysts.

Silicon crystals are the most common semiconducting materials used in microelectronics and photovoltaics. In nanocrystalline materials, the electrons are confined to regions having one, two or three dimensions when the relative dimension is comparable with the de Broglie wavelength. For a semiconductor like CdSe (Cadmium selenide), the de Broglie wavelength of free electron is around 10 nm. The nanostructures of semiconductor crystals having the z direction below this critical value (thin film, layer structure, quantum well) are defined as 2D nanostructures. When the dimension both in the x and z direction is below this critical value (linear chain structure, quantum wire) the nanostructures are defined as 1D and when the y direc-

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tion is also below this threshold (cluster, colloid, nanocrystal, quantum dot) it is referred to as 0D.

Further development of nanotechnology will certainly lead to significant breakthroughs in the semiconductor industry. Semiconductor devices include the various types of transistors, solar cells, many kinds of diodes including the light-emitting diode, the silicon controlled rectifier, and digital and analog integrated circuits. Some of the semiconductor nanomaterials such as Silicon, mixtures of silicon, germanium, arsenic, gallium and etc. exhibit excellent application in computers, palm pilots, laptops, cell phones, pagers, CD players, TV remotes, mobile terminals, satellite dishes, fiber networks, traffic signals, car taillights, and air bags.

Vocabulary development

3. Complete the gaps with the following words from the box.

nanotechnologies, unique, manufacture, colour, efficient, nanoscale, healthcare, lighter, progressively, electricity

Nanomaterials are materials having (1) … properties arising from their

(2) … dimensions - can be stronger or (3) …,or conduct heat or (4) … in a different way. They can even change (5) …; particles of gold can appear red, blue or gold, depending on their size. These special attributes are already being used in a number of ways, such as in the (6) … of computer chips, CDs and mobile phones. Researches are (7) … finding out more about the nanoscale world and aim to use (8) …to create new devices that are faster, lighter, stronger or more (9) …. Nanotechnologies are widely seen as having huge potential in areas as diverse as (10) …, IT and energy storage.

Grammar Focus

4. Translate the following sentences paying attention to Participle Constructions in different syntactic functions.

1.A metal disk implanted in the semiconductor distorts the electric field

lines.

2.Implanted in the semiconductor, a metal disk distorts the electric field

lines.

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3.Spintronic memory being based on magnetic, semiconducting nanoparticles can be used in the future to produce nanostructured computer.

4.Being based on magnetic, semiconducting nanoparticles, spintronic memory provides a promising direction to a nanostructured computer.

5.A voltage applied across the ends of a semiconductor slab (пластина) sets up an electric field.

6.If applied across the ends of a semiconductor slab, a voltage sets up an electric field, the latter causing randomly moving electrons to drift along the slab.

7.The concept of photonic crystals having been theoretically formulated was used later to produce the first photonic crystal.

8.The concept of photonic crystals having been theoretically formulated, the first photonic crystal was fabricated much later.

9.Scientists created new nanomaterials, the latter having tunable electronic properties. The properties of these new nanomaterials being strongly dependent on their location along the nanotube, these new nanomaterials are believed to have far-reaching prospects to design single-molecule devices.

10.The properties of nanomaterials being strongly dependent on their location along the nanotube make these materials suitable for singlemolecule devices.

Speaking

5. Write out the Key sentences of the text. Make up the summary of the text using Key sentences.

UNIT 6. SIZE EFFECTS

Before you read

1. Memorize the following basic vocabulary and terminology

1.quantification – определение количества

2.fall into two categories – разделяться, распадаться

3.moderately sized clusters and nanostructures – кластеры и нано-

структуры средних размеров

4.irregular variation of the relevant property χ(n) – беспорядочное из-

менение значимого свойства χ(n)

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5.in terms of the size equation – выраженное в уравнении размеров

6.scaling law – правило масштабирования

7.nuclear adiabatic dynamics – ядерно-адиабатическая динамика

8.novel fragmentation pattern – новая модель разделения

9.cluster fission and Coulomb explosion – разделение на кластеры и кулоновский взрыв

10.multicharged single clusters – многозарядный единичный кластер

2. Read the text and answer the questions after the text. Size effects

A key concept for the quantification of the unique characteristics of individual nanostructures pertains to size effects. These involve the evolution of structural, thermodynamic, electronic, energetic, spectroscopic, electromagnetic, dynamic, and chemical features of finite systems with increasing size. This concept emerged from cluster chemical physics, but is applicable to other nanostructures (e.g., nanocrystals or nanowires).

Size effects fall into two categories 1) Specific size effects. These involve self-selection and existence of “magic numbers” for small and moderately sized clusters and nanostructures. An irregular variation of the relevant property χ(n) (where n is the number of constitutents), with increasing the size of the nanostructure, is manifested. 2) Smooth size effects for “large” nanostructures. In this size domain, a quantitative description was advanced for the “transition” of the physical and chemical attributes of clusters to the infinite bulk system in terms of the size equation X(n) = X(∞) + Cn–a, where C is the constant and a (a≥ 0) is a positive exponent.

Size equations constitute scaling laws for the nuclear-electronic level structure, energetics, and dynamics, providing the quantitative basis for the description of optical and electrical response of nanostructures. Nuclear adiabatic dynamics of clusters manifests new collective excitations, (e.g., compression modes), which do not have an analog in the bulk. Finite systems exhibit novel fragmentation patterns, such as cluster fission and Coulomb explosion, which are unique for finite systems and do not have an analog in the dynamics of the corresponding bulk matter. A striking example constitutes the dynamics of Coulomb explosion of multicharged single clusters, which may also prevail in nanostructures, whose energetics is characterized by a divergent scaling size equation.

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Comprehension

3. Answer the following questions.

1.What do the size effects involve?

2.What are the two categories the size effects fall into?

3.What was the quantitative description advanced for?

4.What do size equations constitute?

5.What do finite systems demonstrate?

4.Explain the concept “size effect” in your own words the way you understand it.

5.Look through the text again and explain concept “the quantification of the individual nanostructure characteristics”.

Writing

6. Write an abstract on the text. Please remember that an abstract is a secondary document telling a reader what the text is about and does not give any details. Compare and discuss you abstract with a partner.

UNIT 7. NANODEVICES

Before you read

1. Train the pronunciation and translate the international words.

contact, mankind, genius, cog, measurement, mind, scientist, energy, invention, discovery

2. State to what parts of speech the following words belong (pay attention to the suffixes).

Model: equipment – существительное

robotic, holder, discovery, reaction, incredible, electric, scientific, creation, incredible, researcher, surgery, chemical, reaction, movement, continually, combination

3. Spend one minute writing down different words you associate with the word combination “an electric motor”. Share your words with your partner(s) and talk about them.

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4. Read the text and put the correct words from the table in the text below.

Molecular-sized electric motor

Scientists have made the smallest electric motor ever created. It is a (1)

____ of scientific genius that most of us could never even try to understand. Dr. Charles Sykes and his team from America’s Tufts University created the motor from a single molecule (2) ____ a billionth of a metre wide. Dr Sykes is (3) ____ contact with the Guinness Book of World Records to have his motor recognised as the smallest ever. The current world-record holder is a 200-nanometre-(4) ____ nano-tube made from carbon. Dr Sykes’ creation is an incredible 200 times smaller. Naturally, the researchers hope their creation has uses for (5) ____. It will be used to (6) ____ the tiniest machines ever built, and be used by doctors in nano-surgery and robotic surgery.

It is the first time an electric motor has been made from a single molecule. Scientists can make molecules (7) ____ energy from light and chemical reactions into movement, but Dr Sykes’ invention is the first to be (8)

____ as a motor – something that can continually generate power. There is some (9) ____-boggling science behind Sykes’ device. A combination (10)

____ chemicals and metals produces the miniscule motor that rotates 50

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