Nanotechnology – the interdisciplinary field of fundamental and
applied science and technology, which deals with the collection of
theoretical basis and practical methods of investigation, analysis,
and synthesis, as well as methods for the production and use of
products with a given atomic structure by controlled manipulation of
individual atoms and molecules.
Today in the world there is no
standard for how what nanotechnology is, what is nano. The European
Commission set up a special group, which was given two years to
ensure that the classification developed nano.
Among the
approaches to the definition of “nanotechnology” are the
following:
1.In the Technical Committee under the nanotechnology
means:
A knowledge and process management,
as a rule, on a scale of 1 nm, but does not exclude the scale of less
than 100 nanometers in one or more dimensions, when the commissioning
of the size effect (phenomenon) leads to the possibility of new
applications;
B. Using the properties of
objects and materials at the nanometer scale, which differ from those
of the free atoms and molecules, as well as the bulk properties of a
substance consisting of the atoms and molecules to create improved
materials, devices, systems that implement these
properties.
2.Soglasno “Concept of the Russian Federation
works in the field of nanotechnology for the period up to 2010”
Nanotechnology is defined as a set of methods and techniques that
provide a controlled way to create and modify objects, including
components with dimensions less than 100 nm in at least one
dimension, and has resulted in a completely new quality, which they
can be integrated into a fully functioning system of larger
scale.
The practical aspect of nanotechnology involves the
production of devices and components necessary for the creation,
processing and manipulation of atoms, molecules and nanoparticles. It
is understood that it is not necessarily the object must have at
least one linear dimension less than 100 nm – be it micro-objects,
which is controlled by the atomic structure is created with a
resolution at the level of individual atoms, or else contain a
nano-objects. In a broader sense, the term also covers diagnosis,
characterization and study of such objects.
Nanotechnology is
qualitatively different from the traditional disciplines, as usual on
such a scale, the macroscopic treatment technologies often not
matter, and microscopic phenomena, faint disdain for conventional
scales, become much more significant: the properties and interactions
of individual atoms and molecules or aggregates of molecules (eg, Van
der Waals), quantum effects.
Nanotechnology and molecular
technology in particular – new, very little studied discipline. Basic
discoveries predicted in this area until you do. However, ongoing
research has given practical results. The use of nanotechnology in
advanced scientific achievements can attribute it to the high
technology.
The development of modern electronics is on the
way to reduce the size of devices. On the other hand, the classical
methods of production suited to its natural economic and
technological barriers when the device size is reduced slightly, but
the economic costs are increasing exponentially. Nanotechnology – the
next logical step in the development of electronics and other
high-tech industries.
Nanoparticles
The recent trend
towards miniaturization has shown that the substance may have a
completely new properties, if you take a very small part of the
substance. Particles ranging in size from 1 to 100 nanometers,
usually called “nanoparticles”. For example, it was found
that nanoparticles of some materials have a very good catalytic and
adsorption properties. Other data show remarkable optical properties,
such as ultra-thin films of organic materials used for the
manufacture of solar panels. These batteries, though, and have a
relatively low quantum efficiency, but are less expensive and can be
mechanically flexible. Able to bring together the engineered
nanoparticles with natural objects nano – proteins, nucleic acids,
etc. thoroughly purified nanoparticles can samovystraivatsya in
certain structures. This structure contains a strictly ordered
nanoparticles and also often exhibits unusual properties.
A
special class of organic nanoparticles are both natural and
artificial origin.
Since many physical and chemical properties
of nanoparticles, in contrast to bulk materials, are highly dependent
on their size, in recent years there has been considerable interest
in the methods of measuring the size of nanoparticles in solutions:
analysis of the trajectories of the nanoparticles, dynamic light
scattering, sedimentation analysis, ultrasonic methods.
The
latest achievements
Nanomaterials
Materials developed based
on nanoparticles with unique characteristics resulting from the
microscopic size of their constituents.
Carbon
nanotubes – elongated cylindrical structure with a diameter of one to
several tens of nanometers and lengths up to several centimeters,
consisting of one or more rolled into a tube of hexagonal planes of
graphite (graphene), and usually end with a hemispherical
cap.
Fullerenes – molecular compounds
belonging to the class of allotropic forms of carbon (other –
diamond, graphite and carbyne) and is a closed convex polyhedron made
of an even number of carbon atoms trehkoordinirovannyh.
Graphene
– a monolayer of carbon atoms, obtained in October 2004 at the
University of Manchester (The University Of Manchester). Graphene can
be used as a detector molecule (NO2), which allows to detect the
arrival and departure of single molecules. The charge carriers in
graphene have high mobility at room temperature, so that will solve
the problem as soon as the formation of the band gap in this
semimetal, discuss graphene as a promising material to replace
silicon in integrated
circuits.
Nanocrystals
Aerogel
Airbrush
– the hardest material
Nanoakkumulyatory
– at the beginning of 2005, Altair Nanotechnologies (USA) announced
the creation of an innovative nanotechnology material for electrodes
of lithium-ion batteries. Battery with Li4Ti5O12 electrodes are
charging time 10-15 minutes. In February 2006, the company began
production of the batteries at its plant in Indiana. In March 2006,
Altairnano and Boshart Engineering Company signed an agreement to
create a joint electric car. In May 2006, successfully completed the
test car nanoakkumulyatorov. In July 2006, Altair Nanotechnologies
has received the first order for lithium-ion batteries for electric
vehicles.
Self-cleaning surfaces based on
the lotus effect.
Research methods
Due to the fact that
nanotechnology – an interdisciplinary science for research using the
same methods as the “classical” biology, chemistry,
physics. One relatively new research methods in the field of
nanotechnology is a scanning probe microscopy. Currently in the
research labs are not only “classic” probe microscopes, and
SPM in combination with optical microscopes, electron microscopes,
spectrometers, Raman (Raman) scattering and fluorescence
ultramicrotome (for the three-dimensional structure of the
materials.)
Нанотехноло?гия — междисциплинарная
область фундаментальной и прикладной
науки и техники, имеющая дело с
совокупностью теоретического обоснования,
практических методов исследования,
анализа и синтеза, а также методов
производства и применения продуктов с
заданной атомной структурой путём
контролируемого манипулирования
отдельными атомами и молекулами.
На сегодняшний день в мире нет стандарта,
описывающего, что такое нанотехнологии,
что такое нанопродукция. В Еврокомиссии
создана специальная группа, которой
дали два года на то, чтобы разработать
классификацию нанопродукции.
Среди подходов к определению понятия
«нанотехнологии» имеются следующие:
1.В Техническом комитете под нанотехнологиями
подразумевается следующее:
А. знание и управление процессами, как
правило, в масштабе 1 нм, но не исключающее
масштаб менее 100 нм в одном или более
измерениях, когда ввод в действие
размерного эффекта (явления) приводит
к возможности новых применений;
Б. использование свойств объектов и
материалов в нанометровом масштабе,
которые отличаются от свойств свободных
атомов или молекул, а также от объемных
свойств вещества, состоящего из этих
атомов или молекул, для создания более
совершенных материалов, приборов,
систем, реализующих эти свойства.
2.Согласно «Концепции развития в
Российской Федерации работ в области
нанотехнологий на период до 2010 года»
нанотехнология определяется как
совокупность методов и приемов,
обеспечивающих возможность контролируемым
образом создавать и модифицировать
объекты, включающие компоненты с
размерами менее 100 нм, хотя бы в одном
измерении, и в результате этого получившие
принципиально новые качества, позволяющие
осуществлять их интеграцию в полноценно
функционирующие системы большего
масштаба.
Практический аспект нанотехнологий
включает в себя производство устройств
и их компонентов, необходимых для
создания, обработки и манипуляции
атомами, молекулами и наночастицами.
Подразумевается, что не обязательно
объект должен обладать хоть одним
линейным размером менее 100 нм — это
могут быть макрообъекты, атомарная
структура которых контролируемо
создаётся с разрешением на уровне
отдельных атомов, либо же содержащие в
себе нанообъекты. В более широком смысле
этот термин охватывает также методы
диагностики, характерологии и исследований
таких объектов.
Нанотехнологии качественно отличаются
от традиционных дисциплин, поскольку
на таких масштабах привычные,
макроскопические технологии обращения
с материей часто неприменимы, а
микроскопические явления, пренебрежительно
слабые на привычных масштабах, становятся
намного значительнее: свойства и
взаимодействия отдельных атомов и
молекул или агрегатов молекул (например,
силы Ван-дер-Ваальса), квантовые эффекты.
Нанотехнология и в особенности
молекулярная технология — новые, очень
мало исследованные дисциплины. Основные
открытия, предсказываемые в этой области,
пока не сделаны. Тем не менее, проводимые
исследования уже дают практические
результаты. Использование в нанотехнологии
передовых научных достижений позволяет
относить её к высоким технологиям.
Развитие современной электроники идёт
по пути уменьшения размеров устройств.
С другой стороны, классические методы
производства подходят к своему
естественному экономическому и
технологическому барьеру, когда размер
устройства уменьшается ненамного, зато
экономические затраты возрастают
экспоненциально. Нанотехнология —
следующий логический шаг развития
электроники и других наукоёмких
производств.
Наночастицы
Современная тенденция к миниатюризации
показала, что вещество может иметь
совершенно новые свойства, если взять
очень маленькую частицу этого вещества.
Частицы размерами от 1 до 100 нанометров
обычно называют «наночастицами». Так,
например, оказалось, что наночастицы
некоторых материалов имеют очень хорошие
каталитические и адсорбционные свойства.
Другие материалы показывают удивительные
оптические свойства, например, сверхтонкие
пленки органических материалов применяют
для производства солнечных батарей.
Такие батареи, хоть и обладают сравнительно
низкой квантовой эффективностью, зато
более дёшевы и могут быть механически
гибкими. Удается добиться взаимодействия
искусственных наночастиц с природными
объектами наноразмеров — белками,
нуклеиновыми кислотами и др. Тщательно
очищенные наночастицы могут
самовыстраиваться в определённые
структуры. Такая структура содержит
строго упорядоченные наночастицы и
также зачастую проявляет необычные
свойства.
Особый класс составляют органические
наночастицы как естественного, так и
искусственного происхождения.
Поскольку многие физические и химические
свойства наночастиц, в отличие от
объемных материалов, сильно зависят от
их размера, в последние годы проявляется
значительный интерес к методам измерения
размеров наночастиц в растворах: анализ
траекторий наночастиц, динамическое
светорассеяние, седиментационный
анализ, ультразвуковые методы.
Новейшие достижения
Наноматериалы
Материалы, разработанные на основе
наночастиц с уникальными характеристиками,
вытекающими из микроскопических размеров
их составляющих.
Углеродные нанотрубки — протяжённые
цилиндрические структуры диаметром от
одного до нескольких десятков нанометров
и длиной до нескольких сантиметров,
состоящие из одной или нескольких
свёрнутых в трубку гексагональных
графитовых плоскостей (графенов) и
обычно заканчивающиеся полусферической
головкой.
Фуллерены — молекулярные соединения,
принадлежащие классу аллотропных форм
углерода (другие — алмаз, карбин и
графит) и представляющие собой выпуклые
замкнутые многогранники, составленные
из чётного числа трёхкоординированных
атомов углерода.
Графен — монослой атомов углерода,
полученный в октябре 2004 года в Манчестерском
университете (The University
Of Manchester).
Графен можно использовать, как детектор
молекул (NO2), позволяющий
детектировать приход и уход единичных
молекул. Носители зарядов в графене
обладают высокой подвижностью при
комнатной температуре, благодаря чему
как только решат проблему формирования
запрещённой зоны в этом полуметалле,
обсуждают графен как перспективный
материал, который заменит кремний в
интегральных микросхемах.
Нанокристаллы
Аэрогель
Аэрографит — самый твёрдый материал
Наноаккумуляторы — в начале 2005 года
компания Altair Nanotechnologies
(США) объявила о создании инновационного
нанотехнологического материала для
электродов литий-ионных аккумуляторов.
Аккумуляторы с Li4Ti5O12
электродами имеют время зарядки 10-15
минут. В феврале 2006 года компания начала
производство аккумуляторов на своём
заводе в Индиане. В марте 2006 Altairnano
и компания Boshart Engineering
заключили соглашение о совместном
создании электромобиля. В мае 2006 успешно
завершились испытания автомобильных
наноаккумуляторов. В июле 2006 Altair
Nanotechnologies получила первый
заказ на поставку литий-ионных
аккумуляторов для электромобилей.
Самоочищающиеся поверхности на основе
эффекта лотоса.
Методы
исследования
В силу того, что нанотехнология —
междисциплинарная наука, для проведения
научных исследований используют те же
методы, что и «классические» биология,
химия, физика. Одним из относительно
новых методов исследований в области
нанотехнологии является сканирующая
зондовая микроскопия. В настоящее время
в исследовательских лабораториях
используются не только «классические»
зондовые микроскопы, но и СЗМ в комплексе
с оптическими микроскопами, электронными
микроскопами, спектрометрами
комбинационного (рамановского) рассеяния
и флюоресценции, ультрамикротомами
(для получения трёхмерной структуры
материалов).
TERM
PAPER
“NANOTECHNOLOGIES”
Coal and diamonds, sand and computer chips, cancer and healthy tissue:
throughout history, variations in the arrangement of atoms have distinguished the cheap from the cherished, the
diseased from the healthy. Arranged one way, atoms make up soil, air, and water;
arranged another, they make up ripe strawberries. Arranged one way, they make
up homes and fresh air; arranged another, they make up ash and smoke.
Our ability to
arrange atoms lies at the foundation of technology. We have come far in our
atom arranging, from chipping flint for arrowheads to machining aluminum for
spaceships. We take pride in our technology, with our lifesaving drugs and
desktop computers. Yet our spacecraft are still crude, our computers are still
stupid, and the molecules in our tissues still slide into disorder, first
destroying health, then life itself. For all our advances in arranging atoms,
we still use primitive methods. With our present technology, we are still
forced to handle atoms in unruly herds. But the laws of nature leave plenty of
room for progress, and the pressures of world competition are even now pushing
us forward. For better or for worse, the greatest technological breakthrough in
history is still to come.
Two Styles Of Technology
Our modern technology builds on an
ancient tradition. Thirty thousand years ago, chipping flint was the high
technology of the day. Our ancestors grasped stones containing trillions of
trillions of atoms and removed chips containing billions of trillions of atoms
to make their axheads; they made fine work with skills difficult to imitate
today. They also made patterns on cave walls in France
with sprayed paint, using their hands as stencils. Later they made pots by
baking clay, then bronze by cooking rocks. They shaped bronze by pounding it.
They made iron, then steel, and shaped it by heating, pounding, and removing
chips. We now cook up pure ceramics and stronger steels, but we still shape
them by pounding, chipping, and so forth. We cook up pure silicon, saw it into
slices, and make patterns on its surface using tiny stencils and sprays of
light. We call the products “chips” and we consider them exquisitely
small, at least in comparison to axheads. Our microelectronic technology has
managed to stuff machines as powerful as the room-sized computers of the early
1950s onto a few silicon chips in a pocket-sized computer. Engineers are now
making ever smaller devices, slinging herds of atoms at a crystal surface to
build up wires and components one tenth the width of a fine hair. These
microcircuits may be small by the standards of flint chippers, but each
transistor still holds trillions of atoms, and so-called
“microcomputers” are still visible to the naked eye. By the standards
of a newer, more powerful technology they will seem gargantuan. The ancient
style of technology that led from flint chips to silicon chips handles atoms
and molecules in bulk; call it bulk technology. The
new technology will handle individual atoms and molecules with control and
precision; call it molecular technology. It will change our world in more ways
than we can imagine. Microcircuits have parts measured in micrometers – that
is, in millionths of a meter – but molecules are measured in nanometers (a
thousand times smaller). We can use the terms “nanotechnology” and
“molecular technology” interchangeably to describe the new style of
technology. The engineers of the new technology will build both nanocircuits
and nanomachines. Molecular Technology Today
One dictionary
definition of a machine is “any system, usually of rigid bodies, formed
and connected to alter, transmit, and direct applied forces in a predetermined
manner to accomplish a specific objective, such as the performance of useful
work.” Molecular machines fit this definition quite well. To imagine these
machines, one must first picture molecules. We can picture atoms as beads and
molecules as clumps of beads, like a child’s beads linked by snaps. In fact,
chemists do sometimes visualize molecules by building models from plastic beads
(some of which link in several directions, like the hubs in a Tinkertoy set).
Atoms are rounded like beads, and although molecular bonds are not snaps, our
picture at least captures the essential notion that bonds can be broken and
reformed. If an atom were the size of a small marble, a fairly complex molecule would be the
size of your fist. This makes a useful mental image, but atoms are really about
1/10,000 the size of bacteria, and bacteria
are about 1/10,000 the size of mosquitoes. (An atomic nucleus, however, is
about 1/100,000 the size of the atom itself; the difference between an atom and
its nucleus is the difference between a fire and a nuclear reaction.) The
things around us act as they do because of the way their molecules behave. Air
holds neither its shape nor its volume because its molecules move freely,
bumping and ricocheting through open space. Water molecules stick together as
they move about, so water holds a constant volume as it changes shape. Copper
holds its shape because its atoms stick together in regular patterns; we can
bend it and hammer it because its atoms can slip over one another while
remaining bound together. Glass shatters when we hammer it because its atoms
separate before they slip. Rubber consists of networks of kinked molecules,
like a tangle of springs. When stretched and released, its molecules straighten
and then coil again. These simple molecular patterns make up passive
substances. More complex patterns make up the active nanomachines of living cells. Biochemists
already work with these machines, which are chiefly made of protein, the main
engineering material of living cells. These molecular machines have relatively
few atoms, and so they have lumpy surfaces, like objects made by gluing
together a handful of small marbles. Also, many pairs of atoms are linked by
bonds that can bend or rotate, and so protein machines are unusually flexible.
But like all machines, they have parts of different shapes and sizes that do
useful work. All machines use clumps of atoms as parts. Protein machines simply
use very small clumps. Biochemists dream of designing and building such
devices, but there are difficulties to be overcome. Engineers use beams of
light to project patterns onto silicon chips, but chemists must build much more
indirectly than that. When they combine molecules in various sequences, they
have only limited control over how the molecules join. When biochemists need
complex molecular machines, they still have to borrow them from cells.
Nevertheless, advanced molecular machines will eventually let them build
nanocircuits and nanomachines as easily and directly as engineers now build
microcircuits or washing machines. Then progress will become swift and
dramatic. Genetic engineers are already showing the way. Ordinarily, when
chemists make molecular chains – called “polymers” – they dump
molecules into a vessel where they bump and snap together haphazardly in a
liquid. The resulting chains have varying lengths, and the molecules are strung
together in no particular order. But in modern gene synthesis machines,
genetic engineers build more orderly polymers – specific DNA molecules – by
combining molecules in a particular order. These molecules are the nucleotides
of DNA (the letters of the genetic alphabet) and genetic engineers don’t dump
them all in together. Instead, they direct the machine to add different
nucleotides in a particular sequence to spell out a particular message. They
first bond one kind of nucleotide to the
chain ends, then wash away the leftover material and add chemicals to prepare
the chain ends to bond the next nucleotide. They grow chains as they bond on
nucleotides, one at a time, in a programmed sequence. They anchor the very
first nucleotide in each chain to a solid surface to keep the chain from
washing away with its chemical bathwater. In this way, they have a big clumsy
machine in a cabinet assemble specific molecular structures from parts a
hundred million times smaller than itself. But this blind assembly process
accidentally omits nucleotides from some chains. The likelihood of mistakes grows
as chains grow longer. Like workers discarding bad parts before assembling a
car, genetic engineers reduce errors by discarding bad chains. Then, to join
these short chains into working genes (typically thousands of nucleotides
long), they turn to molecular machines found in bacteria. These protein
machines, called restriction enzymes, “read” certain DNA sequences as
“cut here.” They read these genetic patterns by touch, by sticking to
them, and they cut the chain by rearranging a few atoms. Other enzymes splice pieces
together, reading matching parts as “glue here” – likewise
“reading” chains by selective stickiness and splicing chains by
rearranging a few atoms. By using gene machines to write, and restriction
enzymes to cut and paste, genetic engineers can write and edit whatever DNA
messages they choose. But by itself, DNA is a fairly worthless molecule. It is
neither strong like Kevlar, nor colorful like a dye, nor active like an enzyme,
yet it has something that industry is prepared to spend millions of dollars to
use: the ability to direct molecular machines called ribosomes. In cells,
molecular machines first transcribe DNA, copying its information to make RNA “tapes.”
Then, much as old numerically controlled machines shape metal based on
instructions stored on tape, ribosomes build proteins based on instructions
stored on RNA strands. And proteins are useful. Proteins, like DNA, resemble
strings of lumpy beads. But unlike DNA, protein molecules fold up to form small
objects able to do things. Some are enzymes, machines that build up and tear
down molecules (and copy DNA, transcribe it, and build other proteins in the
cycle of life). Other proteins are hormones, binding to yet other proteins to
signal cells to change their behavior. Genetic engineers can produce these
objects cheaply by directing the cheap and efficient molecular machinery inside
living organisms to do the work. Whereas engineers running a chemical plant
must work with vats of reacting chemicals (which often misarrange atoms and
make noxious byproducts), engineers working with bacteria can make them absorb
chemicals, carefully rearrange the atoms, and store a product or release it
into the fluid around them. Genetic engineers have now programmed bacteria to
make proteins ranging from human growth hormone to rennin, an enzyme used in
making cheese. The pharmaceutical company Indianapolis) is now marketing Humulin, human insulin
molecules made by bacteria. Existing Protein Machines
These protein
hormones and enzymes selectively stick to other molecules. An enzyme changes
its target’s structure, then moves on; a hormone affects its target’s behavior
only so long as both remain stuck together. Enzymes and hormones can be
described in mechanical terms, but their behavior is more often described in
chemical terms. But other proteins serve basic
mechanical functions. Some push and pull, some act as cords or
struts, and parts of some molecules make excellent bearings. The machinery of
muscle, for instance, has gangs of proteins that reach, grab a “rope”
(also made of protein), pull it, then reach out again for a fresh grip;
whenever you move, you use these machines. Amoebas and human cells move and
change shape by using fibers and rods that act as molecular muscles and bones.
A reversible,
variable-speed motor drives bacteria through water by turning a
corkscrew-shaped propeller. If a hobbyist could build tiny cars around such
motors, several billions of billions would fit in a pocket, and 150-lane
freeways could be built through your finest capillaries. Simple
molecular devices combine to form systems resembling industrial machines. In
the 1950s engineers developed machine tools that cut metal under the control of
a punched paper tape. A century and a half earlier, Joseph-Marie Jacquard had
built a loom that wove complex patterns under the control of a chain of punched
cards. Yet over three billion years before Jacquard, cells had developed the
machinery of the ribosome. Ribosomes
are proof that nanomachines built of protein and RNA can be programmed to build
complex molecules. Then consider viruses. One kind, the T4 phage,
acts like a spring-loaded syringe and looks like something out of an industrial
parts catalog. It can stick to a bacterium, punch a hole, and inject viral DNA
(yes, even bacteria suffer infections). Like a conqueror seizing factories to
build more tanks, this DNA then directs the cell’s machines to build more viral
DNA and syringes. Like all organisms, these viruses exist because they are
fairly stable and are good at getting copies of themselves made. Whether in
cells or not, nanomachines obey the universal laws of nature. Ordinary chemical
bonds hold their atoms together, and ordinary chemical reactions (guided by
other nanomachines) assemble them. Protein molecules can even join to form
machines without special help, driven only by thermal agitation and chemical
forces. By mixing viral proteins (and the DNA they serve) in a test tube,
molecular biologists have assembled working T4 viruses. This ability
is surprising: imagine putting automotive parts in a large box, shaking it, and
finding an assembled car when you look inside! Yet the T4 virus is but one of
many self-assembling structures.
Molecular biologists have taken the machinery of the ribosome apart into over
fifty separate protein and RNA molecules, and then combined them in test tubes
to form working ribosomes again. To see how this happens, imagine different T4
protein chains floating around in water. Each kind folds up to form a lump with
distinctive bumps and hollows, covered by distinctive patterns of oiliness,
wetness, and electric charge.
Picture them
wandering and tumbling, jostled by the thermal vibrations of the surrounding
water molecules. From time to time two bounce together, then bounce apart.
Sometimes, though, two bounce together and fit, bumps in hollows, with sticky
patches matching; they then pull together and stick. In this way protein adds
to protein to make sections of the virus, and sections assemble to form the
whole. Protein engineers will not need nanoarms and nanohands to assemble
complex nanomachines. Still, tiny manipulators will be useful and they will be
built. Just as today’s engineers build machinery as complex as player pianos
and robot arms from ordinary motors, bearings, and moving parts, so tomorrow’s
biochemists will be able to use protein molecules as motors, bearings, and
moving parts to build robot arms which will themselves be able to handle
individual molecules. Designing with Protein
How far off is
such an ability? Steps have been taken, but much work remains to be done.
Biochemists have already mapped the structures of many proteins. With gene machines
to help write DNA tapes, they can direct cells to build any protein they can design.
But they still don’t know how to design chains that will fold up to make
proteins of the right shape and function. The forces that fold proteins are
weak, and the number of plausible ways a protein might fold is astronomical, so
designing a large protein from scratch isn’t easy. The forces that stick
proteins together to form complex machines are the same ones that fold the
protein chains in the first place. The differing shapes and kinds of stickiness
of amino acids – the
lumpy molecular “beads” forming protein chains – make each protein
chain fold up in a specific way to form an object of a particular shape.
Biochemists have learned rules that suggest how an amino acid chain might fold,
but the rules aren’t very firm. Trying to predict how a chain will fold is like
trying to work a jigsaw puzzle, but a puzzle with no pattern printed on its
pieces to show when the fit is correct, and with pieces that seem to fit
together about as well (or as badly) in many different ways, all but one of
them wrong. False starts could consume many lifetimes, and a correct answer might
not even be recognized. Biochemists using the best computer programs now
available still cannot predict how a long, natural protein chain will actually
fold, and some of them have despaired of designing protein molecules soon. Yet
most biochemists work as scientists, not as engineers. They work at predicting
how natural proteins will fold, not at designing proteins that will fold
predictably. These tasks may sound similar,
but they differ greatly: the first is a scientific challenge, the second is an engineering challenge.
Why should natural proteins fold in a way that scientists will find easy to
predict? All that nature requires is that they in fact fold correctly, not that
they fold in a way obvious to people. Proteins could be designed from the start
with the goal of making their folding more predictable. Carl Pabo, writing in the journal Nature,
has suggested a design strategy based on this insight, and some biochemical
engineers have designed and built short chains of a few dozen
pieces that fold and nestle onto the surfaces of other molecules as
planned. They have designed from scratch a
protein with properties like those of melittin, a toxin in bee
venom. They have modified existing enzymes, changing their behaviors in
predictable ways. Our understanding of proteins is growing daily. In
1959, according to biologist Garrett
Hardin, some geneticists called genetic engineering impossible;
today, it is an industry. Biochemistry and computer-aided design are now
exploding fields, and as Frederick Blattner wrote in the
journal Science, “computer chess programs have already reached
the level below the grand master. Perhaps the solution to the protein-folding
problem is nearer than we think.” Genentech,
writing in Applied Biochemistry and
Biotechnology asks, “How far off is de novo enzyme design and
synthesis? Ten, fifteen years?” He answers, “Perhaps not that
long.” Forrest Carter of the U.S. Naval Research Laboratory,
Ari Aviram and Philip Seiden of IBM, Kevin Ulmer of
Genex Corporation, and other researchers in university and industrial
laboratories around the globe have already begun theoretical work and
experiments aimed at developing molecular switches, memory devices, and other
structures that could be incorporated into a protein-based computer. The U.S.
Naval Research Laboratory has held two international workshops on
molecular electronic devices, and a meeting sponsored by the U.S.
National Science Foundation has recommended support for basic
research aimed at developing molecular computers. Japan has
reportedly begun a multimillion-dollar program aimed at developing
self-assembling molecular motors and computers, and VLSI
Research Inc., of San Jose, reports that “It
looks like the race to bio-chips [another term for molecular electronic
systems] has already started. Sharp have commenced
full-scale research efforts on bio-chips for bio-computers.” Biochemists
have other reasons to want to learn the art of protein design. New enzymes
promise to perform dirty, expensive chemical processes more cheaply and
cleanly, and novel proteins will offer a whole new spectrum of tools to
biotechnologists. We are already on the road to protein engineering, and as
Kevin Ulmer notes in the quote from Science that heads this chapter, this road
leads “toward a more general capability for molecular engineering which
would allow us to structure matter atom by atom.” Second-Generation Nanotechnology
Despite its
versatility, protein has shortcomings as an engineering material. Protein
machines quit when dried, freeze when chilled, and cook when heated. We do not
build machines of flesh, hair, and gelatin; over the centuries, we have learned
to use our hands of flesh and bone to build machines of wood, ceramic, steel,
and plastic. We will do likewise in the future. We will use protein machines to
build nanomachines of tougher stuff than protein. As nanotechnology moves
beyond reliance on proteins, it will grow more ordinary from an engineer’s
point of view. Molecules will be assembled like the components of an erector
set, and well-bonded parts will stay put. Just as ordinary tools can build
ordinary machines from parts, so molecular tools will bond molecules together
to make tiny gears, motors, levers, and casings, and assemble them to make
complex machines. Parts containing only a few atoms will be lumpy, but
engineers can work with lumpy parts if they have smooth bearings to support
them. Conveniently enough, some bonds between atoms make fine bearings; a part
can be mounted by means of a single chemical
bond that will let it turn freely and smoothly. Since a bearing can
be made using only two atoms (and since moving parts need have only a few
atoms), nanomachines can indeed have mechanical components of molecular size.
How will these better machines be built? Over the years, engineers have used
technology to improve technology. They have used metal tools to shape metal
into better tools, and computers to design and program better computers. They
will likewise use protein nanomachines to build better nanomachines. Enzymes
show the way: they assemble large molecules by “grabbing” small
molecules from the water around them, then holding them together so that a bond
forms. Enzymes assemble DNA, RNA, proteins, fats, hormones, and chlorophyll in
this way – indeed, virtually the whole range of molecules found in living
things. Biochemical engineers, then, will construct new enzymes to assemble new
patterns of atoms. For example, they might make an enzyme-like machine which
will add carbon atoms to a small spot, layer on layer. If bonded correctly, the
atoms will build up to form a fine, flexible diamond fiber having
over fifty times as much strength as the same weight of aluminum. Aerospace
companies will line up to buy such fibers by the ton to make advanced
composites. (This shows one small reason why military competition will drive
molecular technology forward, as it has driven so many fields in the past.) But
the great advance will come when protein machines are able to make structures
more complex than mere fibers. These programmable protein machines will
resemble ribosomes programmed by RNA, or the older generation of automated
machine tools programmed by punched tapes. They will open a new world of
possibilities, letting engineers escape the limitations of proteins to build
rugged, compact machines with straightforward designs. Engineered proteins will
split and join molecules as enzymes do. Existing proteins bind a variety of
smaller molecules, using them as chemical tools; newly engineered proteins will
use all these tools and more. Further, organic chemists have shown that
chemical reactions can produce remarkable results even without nanomachines to
guide the molecules. Chemists have no direct control over the tumbling motions
of molecules in a liquid, and so the molecules are free to react in any way
they can, depending on how they bump together. Yet chemists nonetheless coax reacting molecules
to form regular structures such as cubic and dodecahedral molecules, and to
form unlikely-seeming structures such as molecular rings with highly strained
bonds. Molecular machines will have still greater versatility in bondmaking,
because they can use similar molecular motions to make bonds, but can guide
these motions in ways that chemists cannot. Indeed, because chemists cannot yet
direct molecular motions, they can seldom assemble complex molecules according
to specific plans. The largest molecules they can make with specific, complex
patterns are all linear chains. Chemists form these patterns (as in gene
machines) by adding molecules in sequence, one at a time, to a growing chain.
With only one possible bonding site per chain, they can be sure to add the next
piece in the right place. But if a rounded, lumpy molecule has (say) a hundred
hydrogen atoms on its surface, how can chemists split off just one particular
atom (the one five up and three across from the bump on the front) to add
something in its place? Stirring simple chemicals together will seldom do the
job, because small molecules can seldom select specific places to react with a
large molecule. But protein machines will be more choosy. A flexible,
programmable protein machine will grasp a large molecule (the workpiece) while
bringing a small molecule up against it in just the right place. Like an
enzyme, it will then bond the molecules together. By bonding molecule after
molecule to the workpiece, the machine will assemble a larger and larger
structure while keeping complete control of how its atoms are arranged. This is
the key ability that chemists have lacked. Like ribosomes, such nanomachines
can work under the direction of molecular tapes. Unlike ribosomes, they will
handle a wide variety of small molecules (not just amino acids) and will join
them to the workpiece anywhere desired, not just to the end of a chain. Protein
machines will thus combine the splitting and joining abilities of enzymes with
the programmability of ribosomes. But whereas ribosomes can build only the
loose folds of a protein, these protein machines will build small, solid
objects of metal, ceramic, or diamond – invisibly small, but rugged. Where our
fingers of flesh are likely to bruise or burn, we turn to steel tongs. Where
protein machines are likely to crush or disintegrate, we will turn to
nanomachines made of tougher stuff. Universal
Assemblers
Перевод:
Современный человек едва ли может представить свою жизнь без машин. Ежедневно или появляются новые устройства, или улучшаются уже существующие. Люди по-разному относятся к новым изобретениям. Некоторые полагают, что сложные гаджеты на самом деле полезны и необходимо, в то время, как другие считают их ужасными из-за их отрицательного влияния на людей. Что касается меня, я абсолютно уверена в том, что новые устройства делают нашу жизнь легче.
Во-первых, они выполняют всю грязную и тяжелую работу, такую как уборка. Во-вторых, устройства экономят как время, так и место. Например, компьютерный диск может вмещать столько же информации, как несколько толстых книг. Итак, машины помогают людям в разных сферах деятельности.
Однако противники этой точки зрения абсолютно уверены в том, что новые изобретения отрицательно влияют на людей. Люди не хотят работать из-за влияния устройств. Они становятся ленивыми и неорганизованными. Они ждут, когда их последние изобретения сделают всё за них. Более того, по мнению ученых, многие широко распространенные гаджеты обладают излучением, которое может вызвать серьёзные проблемы со здоровьем. Кроме того, всё больше и больше людей становятся зависимыми от компьютера, телевизора или мобильного телефона. Они игнорируют свои домашние обязанности, учебу или работу и проводят всё своё время перед ноутбуком или экраном телевизора.
В заключение, я считаю, что, несмотря на все имеющиеся недостатки, достоинства гаджетов намного более занчительны, так как они экономят время и позволяют людям наслаждаться жизнью!
Каменская Татьяна
We live in the 21st century and we are surrounded by technology. Is it good or is it bad? Let’s think about it.
The first thing that springs to mind is technology is great. It makes our life easier in many ways. For instance we have a lot of kitchen appliances that help us cook, cut, and wash in less time than 20 years ago. So housing has become much less time consuming. It applies to many other areas of our life.
Technologies help us be connected. Most people have some kind of a smart phone that allows them to stay online, share their news with friends and relatives no matter where they are at the moment. Nowadays we have easy access to information, which help in education and business. There are numerous resources that give people opportunity to study at home or be accepted in a university abroad without leaving their home country.
Of course we need to mention technologies used in medicine. They help save lives or improve lives of those who suffered from accidents or were born with some abnormalities. Technologies help us travel in quicker ways. The list of advantages can go and on.
But does technology have disadvantages? It definitely does. The speed with which modern technologies develop and our attempts to catch up with it make our lives more stressful. We have become more isolated, as more and more people replace real relations with social media ones. We virtually don’t need to go out to satisfy our basic needs like food, medicine etc.
Technology definitely improves our lives but only when used in moderation.
Перевод:
Технологии в нашей жизни
Мы живем в XXI веке, и технологии нас окружают. Хорошо это или плохо? Давайте думать.
Первое, что приходит в голову, технологии – это прекрасно. Они упрощают нашу жизнь. Например, сейчас существует много бытовых приборов, которые помогают нам готовить, резать и мыть за меньшее время, чем 20 лет назад. Ведение домашнего хозяйства занимает теперь значительно меньше времени. И это справедливо для многих сфер нашей жизни.
Технологии помогают нам всегда оставаться на связи. У большинства теперь есть смартфон, с помощью которого они выходят в интернет, делятся новостями с друзьями и родственниками, где бы те ни находились. Сегодня очень просто получить доступ к нужной информации, что помогает как в обучении, так и в бизнесе. Существует множество ресурсов, позволяющих обучатся дома, есть возможность поступить в иностранный университет, не уезжая из родной страны.
Конечно, нужно отметить и технологии, используемые в медицине. Они помогают спасать жизни людей и улучшать качество жизни тех, кто пострадал в результате несчастного случая или родился с отклонениями. Технологии позволяют нам путешествовать, тратя все меньше времени. Список преимуществ, которые дают нам технологии, можно продолжать довольно долго.
Но есть ли какие-то недостатки? Определенно есть. Скорость, с которой сейчас развиваются технологии и наши попытки угнаться за прогрессом, наполняют нашу жизнь стрессом. Мы стали более одинокими, поскольку все больше и больше людей предпочитают реальным отношениям виртуальные. Нам в принципе можно не выходить из дома, чтобы удовлетворить базовые потребности в еде, лекарствах и т.д.
Технологии значительно улучшают нашу жизнь, если мы используем их разумно.
Автор — Дарья Царева
We live in the era of high technologies, and we use modern inventions in our everyday life because they have brought us much comfort. New technologies have spread on every field over the past 15 years. Moreover, they are rapidly changing. For example, video-recorders, DVD-players or compact disks have already become obsolete and have been replaced by more up-to-date devices. Today we can hardly imagine our life without such modern mobile devices as cell phones or laptops. Our offices are fully equipped with computers, printers, scanners, air-conditioners, interactive whiteboards and wi-fi modems. Household appliances (vacuum-cleaners, coffee-machines, dish-washers, food processors and others) help us to save our time and energy.
However, we should realize that digital and electronic inventions have both negative and positive impact on our daily life.
I am absolutely positive that new technologies or gadgets are making things faster, easier, more comfortable and interesting. For instance, if you install a GPS (Global Positioning System) in your car you’ll never get lost again. And could we imagine just 15 years ago all the things we can do on the wireless Internet nowadays: connecting with friends from all over the world, online shopping and banking, distance online learning, finding virtual relationships and even working from home? Isn’t that awesome?! Our parents used to go to post-offices to send letters or pay bills, they went to libraries to find a good book and they used telephone-booths for phone-calls.
On the other hand, I know some people who are strongly against some modern inventions because they really miss those days when they talked to each other face to face in reality, and not virtually. I partially agree with that as I really believe that people are becoming anti-social and too dependent on their gadgets. Some of my friends also spend half of the time occupying their shiny gadgets (smart-phones or i-pads) even when we go out together. Besides, people who use various social networks a lot (such as Facebook or Instagram) should worry more about their privacy.
Summing up, I could say that there are serious arguments both for and against the use of new technologies but anyway it’s really difficult to imagine our life without them today.
Новые технологии в нашей жизни
Мы живем в эпоху высоких технологий и пользуемся современными изобретениями в повседневной жизни, поскольку они принесли нам много комфорта. Новые технологии распространились в каждой области за последние 15 лет. Более того, они стремительно меняются. Например, видеомагнитофоны, DVD-плееры или компакт-диски стали уже устаревшими, и им на смену пришли более современные устройства. Сегодня мы с трудом можем представить нашу жизнь без таких современных мобильных приборов, как сотовые телефоны или ноутбуки. Наши офисы полностью оборудованы компьютерами, принтерами, сканерами, кондиционерами, интерактивными досками и wi-fi модемами. Бытовые приборы (пылесосы, кофе-машины, посудомоечные машины, кухонные комбайны и другие) помогают нам экономить время и энергию.
Однако, нам следует понимать, что цифровые и электронные изобретения имеют как отрицательное, так и положительное влияние на нашу повседневную жизнь.
Я полностью согласен с тем, что новые технологии или гаджеты делают многие вещи быстрее, легче, удобнее и интереснее. К примеру, если вы устанавливаете в своем автомобиле GPS (Глобальную Навигационную Систему), вы больше никогда не заблудитесь. А могли ли мы представить всего лишь 15 лет назад все то, что можем делать сегодня по беспроводному интернету: связь с друзьями по всему миру, онлайн покупки и банковские операции, дистанционное онлайн обучение, поиск виртуальных знакомств и даже работу из дома? Разве это не здорово?! Наши родители раньше отправлялись в почтовое отделение для того, чтобы отсылать письма или оплачивать счета, они ходили в библиотеки для того, чтобы найти хорошую книгу и пользовались телефонными будками для того, чтобы позвонить.
С другой стороны, я знаю людей, которые категорически против некоторых современных изобретений, так как им очень не хватает тех дней, когда они общались друг с другом, лицом к лицу в реальности, а не виртуально. Частично я согласен с этим, потому что я считаю, что люди становятся анти-социальными и слишком зависимыми от своих гаджетов. Некоторые мои друзья также посвящают половину времени своим блестящим гаджетам (смартфонам или ай-пэдам), даже когда мы выходим вместе погулять. Кроме того, людям, которые много пользуются социальными сетями (такими, как Фэйсбук или Инстарграм), нужно побеспокоиться о защите своей личной информации.
Подводя итог, я бы сказал, что существуют серьезные аргументы за и против использования новых технологий, но, в любом случае, в наши дни уже будет очень сложно представить жизнь без них.
The final ingredient to nanotechnology is the ability to characterize and predict nanoscale properties and behavior. New experimental tools that are able to “see”, “touch”, and measure the behavior of individual nanostrucures allow scientists and engineers to identify subtle differences in structure and properties that control nanoscale properties. By coupling new experimental techniques with advanced computational tools, researchers can develop, verify, and refine models and simulations that will allow the full potential for nanotechnology to be explored.
There has been much debate on the future implications of nanotechnology. Nanotechnology has the potential to create many new materials and devices with a vast range of applications, such as in medicine, electronics and energy production. On the other hand, nanotechnology raises many of the same issues as with any introduction of new technology, including concerns about the toxicity and environmental impact of nanomaterials, and their potential effects on global economics, as well as speculation about various doomsday scenarios. These concerns have led to a debate among advocacy groups and governments on whether special regulation of nanotechnology is warranted. 4. Compare two columns of words and find Russian equivalents (from the right column) to the following English words (from the left one):
1. На атомном и молекулярном уровне
a) to improve efficiencies of catalysts
2. иметь дело со структурами размеромв 100 миллимикронов
b) as the result of physical and chemical interaction
3. как результат химического и физического взаимодействия
c) on an atomic and molecular scale
4. изменять химические и физические свойства материалов
d) to deal with structures of the size 100 nanometers
5. улучшать эффективность катализаторов
e) to alter physical and chemical properties of materials
6. вырабатывать свет
f) to characterize and predict properties of nanostructures
7. превращать пластичные материалы в твердые
g) to generate light
8. исследовать весь потенциал нанотехнологии
h)to turn ductile materials into solids
9. характеризовать и предсказывать свойства наноструктур
i) effects of nanomaterials on global economics
10. действие наноматериалов на глобальную экономику
j) to explore the full potential of nanotechnology
11. широкий спектр применения наноматериалов
k) concerns about the toxicity of nanomaterials
12. беспокойства по поводу токсичности наноматериалов
l)a vast range of applications of nanomaterials 5. Say whether the following statements are true or false:
1) Nanotechnology is creating an entirely new class of materials and devices with unique and potentially very useful properties.
2) The physical dimensions of nanotechnology are small, spanning from just a few to tens of nanometers.
3) Nanotechnology is very diverse, ranging from extensions of conventional device physics to completely new approaches based upon molecular self-assembly, from developing new materials with dimensions on the nanoscale to investigating whether we can directly control matter on the atomic scale.
4) Nowadays current interest in nanotechnology is not high.
5) The field of nanotechnology is developing slowly as are its practical application.
6) Unique nanoscale properties are already being used to increase energy efficiency and improve healthcare. 6. Answer the following questions:
1) What is nanotechnology?
2) What does nanotechnology deal with?
3) Which properties do materials hundreds of nanometers in size exhibit?
4) What is the final ingredient to nanotechnology?
5) What is the application of nanotechnology?
Эссе
на тему «За» и «Против» нанотехнологии
как качественному переходу от манипуляции
веществом к манипуляции отдельными
атомами»
В
последние десятилетия существенное
внимание уделяется новому направлению
в естественных и технических науках –
нанонауке и нанотехнологии. Согласно
определению Национальной нанотехнологической
инициативы США [1], суть нанотехнологии
заключается в способности работать на
молекулярном уровне, атом за атомом,
создавая большие структуры с фундаментально
новой молекулярной организацией.
Нанотехнология имеет дело с материалами
и системами, структура и компоненты
которых демонстрируют новые и значительно
улучшенные физические, химические и
биологические свойства, явления и
процессы, обусловленные их нанометровым
размером.
Интерес
к нанотехнологии как принципиально
новому возможному методу получения
материалов методом «снизу – вверх»
(т.е. путем сборки материала из отдельных
атомов и молекул) проявился благодаря
выступлению американского физика
Ричарда Фейнмана «There’s Plenty of Room at the
Bottom» [2], в котором он рассмотрел возможность
манипулирования отдельными атомами
как процесс, не противоречащий законам
физики.
Позднее
к идеям конструирования вещества путем
его сборки из отдельных атомов обратился
американский физик и футуролог Эрик
Дрекслер. В 1986 г. вышла его книга «Машины
создания: пришествие эры нанотехнологии»,
в которой он рассмотрел принципы
молекулярной технологии – технологии
манипуляции отдельными атомами и
молекулами, а также молекулярные машины
(ассемблеры) – устройства нанометрового
размера, позволяющих конструировать
молекулы из отдельных атомов по заданному
принципу (аналогично молекулам ДНК в
биологических системах).
Идея
нанотехнологии как процесса манипулирования
отдельными атомами в том виде, в котором
ее представил Дрекслер, вызвала оживленные
споры и негативные отклики. С этической
точки зрения считалось, что разработка
и внедрение такой технологии повлечет
за собой создание новых молекулярных
форм, способных причинить вред всему
живому, выход из-под контроля
устройств-ассемблеров а также их
использования в качестве оружия массового
уничтожения.
Однако,
с точки зрения законов физики и здравого
смысла возможность создания наноассемблеров,
конструирующих молекулы из отдельных
атомов, не была подтверждена, и идеи
Дрекслера так и остались громким
футурологическим прогнозом. Впоследствии
свое предположение отверг и сам Дрекслер
[3].
Однако,
нанотехнология в широком смысле не
ограничивается лишь конструированием
вещества из отдельных атомов. Нанотехнологию
следует рассматривать как умение
целенаправленно создавать и использовать
материалы, устройства и системы, структура
которых регулируется в диапазоне
размеров приблизительно 1-100 нм. Материалы
в таком диапазоне размеров, благодаря
проявлению размерных эффектов, обладают
новыми свойствами, отличающимися от их
крупномасштабных аналогов. В настоящее
время разработано множество способов
применения наноматериалов в различных
областях химии, техники, медицины и т.д.
Использование наноматериалов зачастую
позволяет улучшить характеристики
традиционных материалов или заменить
их, а в некоторых случаях – создать
новые материалы, обладающие ранее
недоступными характеристиками. Данный
аспект применения наноматериалов и
технологий их получения несомненно
является весомым аргументом в поддержку
развития нанонауки и нанотехнологии.
Однако,
важно отметить, что размерные эффекты,
проявляемые в наноматериалах, могут
вызывать также неожиданные негативные
действия. Примером такого отрицательного
воздействия некоторых наноматериалов
является их высокая токсичность и
реакционоспособность. Противники
нанотехнологии в частности и
технологического прогресса в общем
рассматривают данный факт как аргумент
против нанотехнологии. Действительно,
они правы в том, что при разработке
нового материала или новой технологии
следует уделять внимание не только их
преимуществам, но и рассматривать
возможные опасности получаемого
материала или создаваемого метода.
Однако, данной позиции следует
придерживаться любому исследователю,
независимо от области его деятельности. Список используемых источников:
1.
National Nanotechnology Initiative (NNI) http://www.nano.gov
2.
Feynman Richard P.: Classic talk that Richard Feynman gave on
December 29th 1959 at the annual meeting of the American Physical
Society at the California Institute of Technology (Caltech). «There’s
Plenty of Room at the Bottom». http://en.academic.ru/dic.nsf/enwiki/14388
3.
Drexler K. Eric. Engines of Creation 2.0: The Coming Era of
Nanotechnolo-gy – Updated and Expanded. WOWIO
Books, 2007.
So, firstly, modern technologies give us much information about the world. Sitting at home we can learn all news and all details about any event. The use of modern technologies is one of the best ways to explore the world.
Secondly, thanks to modern technologies we can communicate with people, to write letters, to find new friends. It is a real pleasure. When you miss your family, you can call and see the people who are dear to you using Skype.
Thirdly, with the help of modern technologies we can gain different knowledge. We can study various subjects. We can learn everything. It simplifies our life. Modern technologies have a lot of pros, but they have some cons too. You should mind that they may damage your health. But, to my mind, they still have more pros than cons.
Thanks to the Internet you can do almost everything. You can watch movies, play games, make various projects, buy many things, read books, and do many others. Modern technologies help us to relax, for example, when we watch entertainment programs on TV, listen to music…Modern technologies are great helpers in our life. They help us in many ways and simplify our life.
Я хочу затронуть проблему современных технологиях. По моему мнению люди не могут жить без них. ТВ, телефоны, радио, интернет, электронные книги и многое другое все это очень полезные и важные вещи в нашей жизни.
Во первых современные технологии дают нам информацию обо всем мире. Сидя дома мы можем узнать все новости, все подробности любого события. Использование современных технологий один из лучших способов познания мира.
Во вторых мы можем общаться с людьми, писать им письма, находить новых друзей. Это реально круто. Когда ты скучаешь по семье ты можешь позвонить им и увидеть людей которые дороги тебе с помощью скайпа.
В третьих благодаря современным технологиям мы можем получать разнообразные знания. Можем изучать различные предметы. Научится всему. Это упрощает нашу жизнь. Современные технологии имеют много плюсов, но есть и минусы. Вы должны возражать6 что они могут вредить вашему здоровью. Но по моему мнению плюсов больше чем минусов.
Благодаря интернету возможно почти все. Можно смотреть фильмы, играть в игры, составлять различные проекты, делать покупки, читать книжки и многое другое. Современные технологии помогают нам отдыхать, например когда мы смотрим по телевизору развлекательные программы, слушаем музыку… Современные технологии большие помощники в нашей жизни. Они помогают нам во многих вещах и упрощают нашу жизнь
The impact of nanotechnology extends from its medical, ethical, mental, legal and environmental applications, to fields such as engineering, biology, chemistry, computing, materials science, and communications.Major benefits of nanotechnology include improved manufacturing methods, water purification systems, energy systems, physical enhancement, nanomedicine, better food production methods and nutrition and large scale infrastructure auto-fabrication.[vague] Nanotechnology’s reduced size may allow for automation of tasks which were previously inaccessible due to physical restrictions, which in turn may reduce labor, land, or maintenance requirements placed on humans.Potential risks include environmental, health, and safety issues; transitional effects such as displacement of traditional industries as the products of nanotechnology become dominant, which are of concern to privacy rights advocates. These may be particularly important if potential negative effects of nanoparticles are overlooked.Whether nanotechnology merits special government regulation is a controversial issue. Regulatory bodies such as the United States Environmental Protection Agency and the Health & Consumer Protection Directorate of the European Commission have started dealing with the potential risks of nanoparticles. The organic food sector has been the first to act with the regulated exclusion of engineered nanoparticles from certified organic produce, firstly in Australia and the UK,[1] and more recently in Canada, as well as for all food certified to Demeter International standards
Nanotechnology – the interdisciplinary field of fundamental and
applied science and technology, which deals with the collection of
theoretical basis and practical methods of investigation, analysis,
and synthesis, as well as methods for the production and use of
products with a given atomic structure by controlled manipulation of
individual atoms and molecules.
Today in the world there is no
standard for how what nanotechnology is, what is nano. The European
Commission set up a special group, which was given two years to
ensure that the classification developed nano.
Among the
approaches to the definition of “nanotechnology” are the
following:
1.In the Technical Committee under the nanotechnology
means:
A knowledge and process management,
as a rule, on a scale of 1 nm, but does not exclude the scale of less
than 100 nanometers in one or more dimensions, when the commissioning
of the size effect (phenomenon) leads to the possibility of new
applications;
B. Using the properties of
objects and materials at the nanometer scale, which differ from those
of the free atoms and molecules, as well as the bulk properties of a
substance consisting of the atoms and molecules to create improved
materials, devices, systems that implement these
properties.
2.Soglasno “Concept of the Russian Federation
works in the field of nanotechnology for the period up to 2010”
Nanotechnology is defined as a set of methods and techniques that
provide a controlled way to create and modify objects, including
components with dimensions less than 100 nm in at least one
dimension, and has resulted in a completely new quality, which they
can be integrated into a fully functioning system of larger
scale.
The practical aspect of nanotechnology involves the
production of devices and components necessary for the creation,
processing and manipulation of atoms, molecules and nanoparticles. It
is understood that it is not necessarily the object must have at
least one linear dimension less than 100 nm – be it micro-objects,
which is controlled by the atomic structure is created with a
resolution at the level of individual atoms, or else contain a
nano-objects. In a broader sense, the term also covers diagnosis,
characterization and study of such objects.
Nanotechnology is
qualitatively different from the traditional disciplines, as usual on
such a scale, the macroscopic treatment technologies often not
matter, and microscopic phenomena, faint disdain for conventional
scales, become much more significant: the properties and interactions
of individual atoms and molecules or aggregates of molecules (eg, Van
der Waals), quantum effects.
Nanotechnology and molecular
technology in particular – new, very little studied discipline. Basic
discoveries predicted in this area until you do. However, ongoing
research has given practical results. The use of nanotechnology in
advanced scientific achievements can attribute it to the high
technology.
The development of modern electronics is on the
way to reduce the size of devices. On the other hand, the classical
methods of production suited to its natural economic and
technological barriers when the device size is reduced slightly, but
the economic costs are increasing exponentially. Nanotechnology – the
next logical step in the development of electronics and other
high-tech industries.
Nanoparticles
The recent trend
towards miniaturization has shown that the substance may have a
completely new properties, if you take a very small part of the
substance. Particles ranging in size from 1 to 100 nanometers,
usually called “nanoparticles”. For example, it was found
that nanoparticles of some materials have a very good catalytic and
adsorption properties. Other data show remarkable optical properties,
such as ultra-thin films of organic materials used for the
manufacture of solar panels. These batteries, though, and have a
relatively low quantum efficiency, but are less expensive and can be
mechanically flexible. Able to bring together the engineered
nanoparticles with natural objects nano – proteins, nucleic acids,
etc. thoroughly purified nanoparticles can samovystraivatsya in
certain structures. This structure contains a strictly ordered
nanoparticles and also often exhibits unusual properties.
A
special class of organic nanoparticles are both natural and
artificial origin.
Since many physical and chemical properties
of nanoparticles, in contrast to bulk materials, are highly dependent
on their size, in recent years there has been considerable interest
in the methods of measuring the size of nanoparticles in solutions:
analysis of the trajectories of the nanoparticles, dynamic light
scattering, sedimentation analysis, ultrasonic methods.
The
latest achievements
Nanomaterials
Materials developed based
on nanoparticles with unique characteristics resulting from the
microscopic size of their constituents.
Carbon
nanotubes – elongated cylindrical structure with a diameter of one to
several tens of nanometers and lengths up to several centimeters,
consisting of one or more rolled into a tube of hexagonal planes of
graphite (graphene), and usually end with a hemispherical
cap.
Fullerenes – molecular compounds
belonging to the class of allotropic forms of carbon (other –
diamond, graphite and carbyne) and is a closed convex polyhedron made
of an even number of carbon atoms trehkoordinirovannyh.
Graphene
– a monolayer of carbon atoms, obtained in October 2004 at the
University of Manchester (The University Of Manchester). Graphene can
be used as a detector molecule (NO2), which allows to detect the
arrival and departure of single molecules. The charge carriers in
graphene have high mobility at room temperature, so that will solve
the problem as soon as the formation of the band gap in this
semimetal, discuss graphene as a promising material to replace
silicon in integrated
circuits.
Nanocrystals
Aerogel
Airbrush
– the hardest material
Nanoakkumulyatory
– at the beginning of 2005, Altair Nanotechnologies (USA) announced
the creation of an innovative nanotechnology material for electrodes
of lithium-ion batteries. Battery with Li4Ti5O12 electrodes are
charging time 10-15 minutes. In February 2006, the company began
production of the batteries at its plant in Indiana. In March 2006,
Altairnano and Boshart Engineering Company signed an agreement to
create a joint electric car. In May 2006, successfully completed the
test car nanoakkumulyatorov. In July 2006, Altair Nanotechnologies
has received the first order for lithium-ion batteries for electric
vehicles.
Self-cleaning surfaces based on
the lotus effect.
Research methods
Due to the fact that
nanotechnology – an interdisciplinary science for research using the
same methods as the “classical” biology, chemistry,
physics. One relatively new research methods in the field of
nanotechnology is a scanning probe microscopy. Currently in the
research labs are not only “classic” probe microscopes, and
SPM in combination with optical microscopes, electron microscopes,
spectrometers, Raman (Raman) scattering and fluorescence
ultramicrotome (for the three-dimensional structure of the
materials.)
Нанотехноло?гия — междисциплинарная
область фундаментальной и прикладной
науки и техники, имеющая дело с
совокупностью теоретического обоснования,
практических методов исследования,
анализа и синтеза, а также методов
производства и применения продуктов с
заданной атомной структурой путём
контролируемого манипулирования
отдельными атомами и молекулами.
На сегодняшний день в мире нет стандарта,
описывающего, что такое нанотехнологии,
что такое нанопродукция. В Еврокомиссии
создана специальная группа, которой
дали два года на то, чтобы разработать
классификацию нанопродукции.
Среди подходов к определению понятия
«нанотехнологии» имеются следующие:
1.В Техническом комитете под нанотехнологиями
подразумевается следующее:
А. знание и управление процессами, как
правило, в масштабе 1 нм, но не исключающее
масштаб менее 100 нм в одном или более
измерениях, когда ввод в действие
размерного эффекта (явления) приводит
к возможности новых применений;
Б. использование свойств объектов и
материалов в нанометровом масштабе,
которые отличаются от свойств свободных
атомов или молекул, а также от объемных
свойств вещества, состоящего из этих
атомов или молекул, для создания более
совершенных материалов, приборов,
систем, реализующих эти свойства.
2.Согласно «Концепции развития в
Российской Федерации работ в области
нанотехнологий на период до 2010 года»
нанотехнология определяется как
совокупность методов и приемов,
обеспечивающих возможность контролируемым
образом создавать и модифицировать
объекты, включающие компоненты с
размерами менее 100 нм, хотя бы в одном
измерении, и в результате этого получившие
принципиально новые качества, позволяющие
осуществлять их интеграцию в полноценно
функционирующие системы большего
масштаба.
Практический аспект нанотехнологий
включает в себя производство устройств
и их компонентов, необходимых для
создания, обработки и манипуляции
атомами, молекулами и наночастицами.
Подразумевается, что не обязательно
объект должен обладать хоть одним
линейным размером менее 100 нм — это
могут быть макрообъекты, атомарная
структура которых контролируемо
создаётся с разрешением на уровне
отдельных атомов, либо же содержащие в
себе нанообъекты. В более широком смысле
этот термин охватывает также методы
диагностики, характерологии и исследований
таких объектов.
Нанотехнологии качественно отличаются
от традиционных дисциплин, поскольку
на таких масштабах привычные,
макроскопические технологии обращения
с материей часто неприменимы, а
микроскопические явления, пренебрежительно
слабые на привычных масштабах, становятся
намного значительнее: свойства и
взаимодействия отдельных атомов и
молекул или агрегатов молекул (например,
силы Ван-дер-Ваальса), квантовые эффекты.
Нанотехнология и в особенности
молекулярная технология — новые, очень
мало исследованные дисциплины. Основные
открытия, предсказываемые в этой области,
пока не сделаны. Тем не менее, проводимые
исследования уже дают практические
результаты. Использование в нанотехнологии
передовых научных достижений позволяет
относить её к высоким технологиям.
Развитие современной электроники идёт
по пути уменьшения размеров устройств.
С другой стороны, классические методы
производства подходят к своему
естественному экономическому и
технологическому барьеру, когда размер
устройства уменьшается ненамного, зато
экономические затраты возрастают
экспоненциально. Нанотехнология —
следующий логический шаг развития
электроники и других наукоёмких
производств.
Наночастицы
Современная тенденция к миниатюризации
показала, что вещество может иметь
совершенно новые свойства, если взять
очень маленькую частицу этого вещества.
Частицы размерами от 1 до 100 нанометров
обычно называют «наночастицами». Так,
например, оказалось, что наночастицы
некоторых материалов имеют очень хорошие
каталитические и адсорбционные свойства.
Другие материалы показывают удивительные
оптические свойства, например, сверхтонкие
пленки органических материалов применяют
для производства солнечных батарей.
Такие батареи, хоть и обладают сравнительно
низкой квантовой эффективностью, зато
более дёшевы и могут быть механически
гибкими. Удается добиться взаимодействия
искусственных наночастиц с природными
объектами наноразмеров — белками,
нуклеиновыми кислотами и др. Тщательно
очищенные наночастицы могут
самовыстраиваться в определённые
структуры. Такая структура содержит
строго упорядоченные наночастицы и
также зачастую проявляет необычные
свойства.
Особый класс составляют органические
наночастицы как естественного, так и
искусственного происхождения.
Поскольку многие физические и химические
свойства наночастиц, в отличие от
объемных материалов, сильно зависят от
их размера, в последние годы проявляется
значительный интерес к методам измерения
размеров наночастиц в растворах: анализ
траекторий наночастиц, динамическое
светорассеяние, седиментационный
анализ, ультразвуковые методы.
Новейшие достижения
Наноматериалы
Материалы, разработанные на основе
наночастиц с уникальными характеристиками,
вытекающими из микроскопических размеров
их составляющих.
Углеродные нанотрубки — протяжённые
цилиндрические структуры диаметром от
одного до нескольких десятков нанометров
и длиной до нескольких сантиметров,
состоящие из одной или нескольких
свёрнутых в трубку гексагональных
графитовых плоскостей (графенов) и
обычно заканчивающиеся полусферической
головкой.
Фуллерены — молекулярные соединения,
принадлежащие классу аллотропных форм
углерода (другие — алмаз, карбин и
графит) и представляющие собой выпуклые
замкнутые многогранники, составленные
из чётного числа трёхкоординированных
атомов углерода.
Графен — монослой атомов углерода,
полученный в октябре 2004 года в Манчестерском
университете (The University
Of Manchester).
Графен можно использовать, как детектор
молекул (NO2), позволяющий
детектировать приход и уход единичных
молекул. Носители зарядов в графене
обладают высокой подвижностью при
комнатной температуре, благодаря чему
как только решат проблему формирования
запрещённой зоны в этом полуметалле,
обсуждают графен как перспективный
материал, который заменит кремний в
интегральных микросхемах.
Нанокристаллы
Аэрогель
Аэрографит — самый твёрдый материал
Наноаккумуляторы — в начале 2005 года
компания Altair Nanotechnologies
(США) объявила о создании инновационного
нанотехнологического материала для
электродов литий-ионных аккумуляторов.
Аккумуляторы с Li4Ti5O12
электродами имеют время зарядки 10-15
минут. В феврале 2006 года компания начала
производство аккумуляторов на своём
заводе в Индиане. В марте 2006 Altairnano
и компания Boshart Engineering
заключили соглашение о совместном
создании электромобиля. В мае 2006 успешно
завершились испытания автомобильных
наноаккумуляторов. В июле 2006 Altair
Nanotechnologies получила первый
заказ на поставку литий-ионных
аккумуляторов для электромобилей.
Самоочищающиеся поверхности на основе
эффекта лотоса.
Методы
исследования
В силу того, что нанотехнология —
междисциплинарная наука, для проведения
научных исследований используют те же
методы, что и «классические» биология,
химия, физика. Одним из относительно
новых методов исследований в области
нанотехнологии является сканирующая
зондовая микроскопия. В настоящее время
в исследовательских лабораториях
используются не только «классические»
зондовые микроскопы, но и СЗМ в комплексе
с оптическими микроскопами, электронными
микроскопами, спектрометрами
комбинационного (рамановского) рассеяния
и флюоресценции, ультрамикротомами
(для получения трёхмерной структуры
материалов).
TERM
PAPER
“NANOTECHNOLOGIES”
Coal and diamonds, sand and computer chips, cancer and healthy tissue:
throughout history, variations in the arrangement of atoms have distinguished the cheap from the cherished, the
diseased from the healthy. Arranged one way, atoms make up soil, air, and water;
arranged another, they make up ripe strawberries. Arranged one way, they make
up homes and fresh air; arranged another, they make up ash and smoke.
Our ability to
arrange atoms lies at the foundation of technology. We have come far in our
atom arranging, from chipping flint for arrowheads to machining aluminum for
spaceships. We take pride in our technology, with our lifesaving drugs and
desktop computers. Yet our spacecraft are still crude, our computers are still
stupid, and the molecules in our tissues still slide into disorder, first
destroying health, then life itself. For all our advances in arranging atoms,
we still use primitive methods. With our present technology, we are still
forced to handle atoms in unruly herds. But the laws of nature leave plenty of
room for progress, and the pressures of world competition are even now pushing
us forward. For better or for worse, the greatest technological breakthrough in
history is still to come.
Two Styles Of Technology
Our modern technology builds on an
ancient tradition. Thirty thousand years ago, chipping flint was the high
technology of the day. Our ancestors grasped stones containing trillions of
trillions of atoms and removed chips containing billions of trillions of atoms
to make their axheads; they made fine work with skills difficult to imitate
today. They also made patterns on cave walls in France
with sprayed paint, using their hands as stencils. Later they made pots by
baking clay, then bronze by cooking rocks. They shaped bronze by pounding it.
They made iron, then steel, and shaped it by heating, pounding, and removing
chips. We now cook up pure ceramics and stronger steels, but we still shape
them by pounding, chipping, and so forth. We cook up pure silicon, saw it into
slices, and make patterns on its surface using tiny stencils and sprays of
light. We call the products “chips” and we consider them exquisitely
small, at least in comparison to axheads. Our microelectronic technology has
managed to stuff machines as powerful as the room-sized computers of the early
1950s onto a few silicon chips in a pocket-sized computer. Engineers are now
making ever smaller devices, slinging herds of atoms at a crystal surface to
build up wires and components one tenth the width of a fine hair. These
microcircuits may be small by the standards of flint chippers, but each
transistor still holds trillions of atoms, and so-called
“microcomputers” are still visible to the naked eye. By the standards
of a newer, more powerful technology they will seem gargantuan. The ancient
style of technology that led from flint chips to silicon chips handles atoms
and molecules in bulk; call it bulk technology. The
new technology will handle individual atoms and molecules with control and
precision; call it molecular technology. It will change our world in more ways
than we can imagine. Microcircuits have parts measured in micrometers – that
is, in millionths of a meter – but molecules are measured in nanometers (a
thousand times smaller). We can use the terms “nanotechnology” and
“molecular technology” interchangeably to describe the new style of
technology. The engineers of the new technology will build both nanocircuits
and nanomachines.
Molecular Technology Today
One dictionary
definition of a machine is “any system, usually of rigid bodies, formed
and connected to alter, transmit, and direct applied forces in a predetermined
manner to accomplish a specific objective, such as the performance of useful
work.” Molecular machines fit this definition quite well. To imagine these
machines, one must first picture molecules. We can picture atoms as beads and
molecules as clumps of beads, like a child’s beads linked by snaps. In fact,
chemists do sometimes visualize molecules by building models from plastic beads
(some of which link in several directions, like the hubs in a Tinkertoy set).
Atoms are rounded like beads, and although molecular bonds are not snaps, our
picture at least captures the essential notion that bonds can be broken and
reformed. If an atom were the size of a small marble, a fairly complex molecule would be the
size of your fist. This makes a useful mental image, but atoms are really about
1/10,000 the size of bacteria, and bacteria
are about 1/10,000 the size of mosquitoes. (An atomic nucleus, however, is
about 1/100,000 the size of the atom itself; the difference between an atom and
its nucleus is the difference between a fire and a nuclear reaction.) The
things around us act as they do because of the way their molecules behave. Air
holds neither its shape nor its volume because its molecules move freely,
bumping and ricocheting through open space. Water molecules stick together as
they move about, so water holds a constant volume as it changes shape. Copper
holds its shape because its atoms stick together in regular patterns; we can
bend it and hammer it because its atoms can slip over one another while
remaining bound together. Glass shatters when we hammer it because its atoms
separate before they slip. Rubber consists of networks of kinked molecules,
like a tangle of springs. When stretched and released, its molecules straighten
and then coil again. These simple molecular patterns make up passive
substances. More complex patterns make up the active nanomachines of living cells. Biochemists
already work with these machines, which are chiefly made of protein, the main
engineering material of living cells. These molecular machines have relatively
few atoms, and so they have lumpy surfaces, like objects made by gluing
together a handful of small marbles. Also, many pairs of atoms are linked by
bonds that can bend or rotate, and so protein machines are unusually flexible.
But like all machines, they have parts of different shapes and sizes that do
useful work. All machines use clumps of atoms as parts. Protein machines simply
use very small clumps. Biochemists dream of designing and building such
devices, but there are difficulties to be overcome. Engineers use beams of
light to project patterns onto silicon chips, but chemists must build much more
indirectly than that. When they combine molecules in various sequences, they
have only limited control over how the molecules join. When biochemists need
complex molecular machines, they still have to borrow them from cells.
Nevertheless, advanced molecular machines will eventually let them build
nanocircuits and nanomachines as easily and directly as engineers now build
microcircuits or washing machines. Then progress will become swift and
dramatic. Genetic engineers are already showing the way. Ordinarily, when
chemists make molecular chains – called “polymers” – they dump
molecules into a vessel where they bump and snap together haphazardly in a
liquid. The resulting chains have varying lengths, and the molecules are strung
together in no particular order. But in modern gene synthesis machines,
genetic engineers build more orderly polymers – specific DNA molecules – by
combining molecules in a particular order. These molecules are the nucleotides
of DNA (the letters of the genetic alphabet) and genetic engineers don’t dump
them all in together. Instead, they direct the machine to add different
nucleotides in a particular sequence to spell out a particular message. They
first bond one kind of nucleotide to the
chain ends, then wash away the leftover material and add chemicals to prepare
the chain ends to bond the next nucleotide. They grow chains as they bond on
nucleotides, one at a time, in a programmed sequence. They anchor the very
first nucleotide in each chain to a solid surface to keep the chain from
washing away with its chemical bathwater. In this way, they have a big clumsy
machine in a cabinet assemble specific molecular structures from parts a
hundred million times smaller than itself. But this blind assembly process
accidentally omits nucleotides from some chains. The likelihood of mistakes grows
as chains grow longer. Like workers discarding bad parts before assembling a
car, genetic engineers reduce errors by discarding bad chains. Then, to join
these short chains into working genes (typically thousands of nucleotides
long), they turn to molecular machines found in bacteria. These protein
machines, called restriction enzymes, “read” certain DNA sequences as
“cut here.” They read these genetic patterns by touch, by sticking to
them, and they cut the chain by rearranging a few atoms. Other enzymes splice pieces
together, reading matching parts as “glue here” – likewise
“reading” chains by selective stickiness and splicing chains by
rearranging a few atoms. By using gene machines to write, and restriction
enzymes to cut and paste, genetic engineers can write and edit whatever DNA
messages they choose. But by itself, DNA is a fairly worthless molecule. It is
neither strong like Kevlar, nor colorful like a dye, nor active like an enzyme,
yet it has something that industry is prepared to spend millions of dollars to
use: the ability to direct molecular machines called ribosomes. In cells,
molecular machines first transcribe DNA, copying its information to make RNA “tapes.”
Then, much as old numerically controlled machines shape metal based on
instructions stored on tape, ribosomes build proteins based on instructions
stored on RNA strands. And proteins are useful. Proteins, like DNA, resemble
strings of lumpy beads. But unlike DNA, protein molecules fold up to form small
objects able to do things. Some are enzymes, machines that build up and tear
down molecules (and copy DNA, transcribe it, and build other proteins in the
cycle of life). Other proteins are hormones, binding to yet other proteins to
signal cells to change their behavior. Genetic engineers can produce these
objects cheaply by directing the cheap and efficient molecular machinery inside
living organisms to do the work. Whereas engineers running a chemical plant
must work with vats of reacting chemicals (which often misarrange atoms and
make noxious byproducts), engineers working with bacteria can make them absorb
chemicals, carefully rearrange the atoms, and store a product or release it
into the fluid around them. Genetic engineers have now programmed bacteria to
make proteins ranging from human growth hormone to rennin, an enzyme used in
making cheese. The pharmaceutical company Indianapolis) is now marketing Humulin, human insulin
molecules made by bacteria.
Existing Protein Machines
These protein
hormones and enzymes selectively stick to other molecules. An enzyme changes
its target’s structure, then moves on; a hormone affects its target’s behavior
only so long as both remain stuck together. Enzymes and hormones can be
described in mechanical terms, but their behavior is more often described in
chemical terms. But other proteins serve basic
mechanical functions. Some push and pull, some act as cords or
struts, and parts of some molecules make excellent bearings. The machinery of
muscle, for instance, has gangs of proteins that reach, grab a “rope”
(also made of protein), pull it, then reach out again for a fresh grip;
whenever you move, you use these machines. Amoebas and human cells move and
change shape by using fibers and rods that act as molecular muscles and bones.
A reversible,
variable-speed motor drives bacteria through water by turning a
corkscrew-shaped propeller. If a hobbyist could build tiny cars around such
motors, several billions of billions would fit in a pocket, and 150-lane
freeways could be built through your finest capillaries. Simple
molecular devices combine to form systems resembling industrial machines. In
the 1950s engineers developed machine tools that cut metal under the control of
a punched paper tape. A century and a half earlier, Joseph-Marie Jacquard had
built a loom that wove complex patterns under the control of a chain of punched
cards. Yet over three billion years before Jacquard, cells had developed the
machinery of the ribosome. Ribosomes
are proof that nanomachines built of protein and RNA can be programmed to build
complex molecules. Then consider viruses. One kind, the T4 phage,
acts like a spring-loaded syringe and looks like something out of an industrial
parts catalog. It can stick to a bacterium, punch a hole, and inject viral DNA
(yes, even bacteria suffer infections). Like a conqueror seizing factories to
build more tanks, this DNA then directs the cell’s machines to build more viral
DNA and syringes. Like all organisms, these viruses exist because they are
fairly stable and are good at getting copies of themselves made. Whether in
cells or not, nanomachines obey the universal laws of nature. Ordinary chemical
bonds hold their atoms together, and ordinary chemical reactions (guided by
other nanomachines) assemble them. Protein molecules can even join to form
machines without special help, driven only by thermal agitation and chemical
forces. By mixing viral proteins (and the DNA they serve) in a test tube,
molecular biologists have assembled working T4 viruses. This ability
is surprising: imagine putting automotive parts in a large box, shaking it, and
finding an assembled car when you look inside! Yet the T4 virus is but one of
many self-assembling structures.
Molecular biologists have taken the machinery of the ribosome apart into over
fifty separate protein and RNA molecules, and then combined them in test tubes
to form working ribosomes again. To see how this happens, imagine different T4
protein chains floating around in water. Each kind folds up to form a lump with
distinctive bumps and hollows, covered by distinctive patterns of oiliness,
wetness, and electric charge.
Picture them
wandering and tumbling, jostled by the thermal vibrations of the surrounding
water molecules. From time to time two bounce together, then bounce apart.
Sometimes, though, two bounce together and fit, bumps in hollows, with sticky
patches matching; they then pull together and stick. In this way protein adds
to protein to make sections of the virus, and sections assemble to form the
whole. Protein engineers will not need nanoarms and nanohands to assemble
complex nanomachines. Still, tiny manipulators will be useful and they will be
built. Just as today’s engineers build machinery as complex as player pianos
and robot arms from ordinary motors, bearings, and moving parts, so tomorrow’s
biochemists will be able to use protein molecules as motors, bearings, and
moving parts to build robot arms which will themselves be able to handle
individual molecules.
Designing with Protein
How far off is
such an ability? Steps have been taken, but much work remains to be done.
Biochemists have already mapped the structures of many proteins. With gene machines
to help write DNA tapes, they can direct cells to build any protein they can design.
But they still don’t know how to design chains that will fold up to make
proteins of the right shape and function. The forces that fold proteins are
weak, and the number of plausible ways a protein might fold is astronomical, so
designing a large protein from scratch isn’t easy. The forces that stick
proteins together to form complex machines are the same ones that fold the
protein chains in the first place. The differing shapes and kinds of stickiness
of amino acids – the
lumpy molecular “beads” forming protein chains – make each protein
chain fold up in a specific way to form an object of a particular shape.
Biochemists have learned rules that suggest how an amino acid chain might fold,
but the rules aren’t very firm. Trying to predict how a chain will fold is like
trying to work a jigsaw puzzle, but a puzzle with no pattern printed on its
pieces to show when the fit is correct, and with pieces that seem to fit
together about as well (or as badly) in many different ways, all but one of
them wrong. False starts could consume many lifetimes, and a correct answer might
not even be recognized. Biochemists using the best computer programs now
available still cannot predict how a long, natural protein chain will actually
fold, and some of them have despaired of designing protein molecules soon. Yet
most biochemists work as scientists, not as engineers. They work at predicting
how natural proteins will fold, not at designing proteins that will fold
predictably. These tasks may sound similar,
but they differ greatly: the first is a scientific challenge, the second is an engineering challenge.
Why should natural proteins fold in a way that scientists will find easy to
predict? All that nature requires is that they in fact fold correctly, not that
they fold in a way obvious to people. Proteins could be designed from the start
with the goal of making their folding more predictable. Carl Pabo, writing in the journal Nature,
has suggested a design strategy based on this insight, and some biochemical
engineers have designed and built short chains of a few dozen
pieces that fold and nestle onto the surfaces of other molecules as
planned. They have designed from scratch a
protein with properties like those of melittin, a toxin in bee
venom. They have modified existing enzymes, changing their behaviors in
predictable ways. Our understanding of proteins is growing daily. In
1959, according to biologist Garrett
Hardin, some geneticists called genetic engineering impossible;
today, it is an industry. Biochemistry and computer-aided design are now
exploding fields, and as Frederick Blattner wrote in the
journal Science, “computer chess programs have already reached
the level below the grand master. Perhaps the solution to the protein-folding
problem is nearer than we think.” Genentech,
writing in Applied Biochemistry and
Biotechnology asks, “How far off is de novo enzyme design and
synthesis? Ten, fifteen years?” He answers, “Perhaps not that
long.” Forrest Carter of the U.S. Naval Research Laboratory,
Ari Aviram and Philip Seiden of IBM, Kevin Ulmer of
Genex Corporation, and other researchers in university and industrial
laboratories around the globe have already begun theoretical work and
experiments aimed at developing molecular switches, memory devices, and other
structures that could be incorporated into a protein-based computer. The U.S.
Naval Research Laboratory has held two international workshops on
molecular electronic devices, and a meeting sponsored by the U.S.
National Science Foundation has recommended support for basic
research aimed at developing molecular computers. Japan has
reportedly begun a multimillion-dollar program aimed at developing
self-assembling molecular motors and computers, and VLSI
Research Inc., of San Jose, reports that “It
looks like the race to bio-chips [another term for molecular electronic
systems] has already started. Sharp have commenced
full-scale research efforts on bio-chips for bio-computers.” Biochemists
have other reasons to want to learn the art of protein design. New enzymes
promise to perform dirty, expensive chemical processes more cheaply and
cleanly, and novel proteins will offer a whole new spectrum of tools to
biotechnologists. We are already on the road to protein engineering, and as
Kevin Ulmer notes in the quote from Science that heads this chapter, this road
leads “toward a more general capability for molecular engineering which
would allow us to structure matter atom by atom.”
Second-Generation Nanotechnology
Despite its
versatility, protein has shortcomings as an engineering material. Protein
machines quit when dried, freeze when chilled, and cook when heated. We do not
build machines of flesh, hair, and gelatin; over the centuries, we have learned
to use our hands of flesh and bone to build machines of wood, ceramic, steel,
and plastic. We will do likewise in the future. We will use protein machines to
build nanomachines of tougher stuff than protein. As nanotechnology moves
beyond reliance on proteins, it will grow more ordinary from an engineer’s
point of view. Molecules will be assembled like the components of an erector
set, and well-bonded parts will stay put. Just as ordinary tools can build
ordinary machines from parts, so molecular tools will bond molecules together
to make tiny gears, motors, levers, and casings, and assemble them to make
complex machines. Parts containing only a few atoms will be lumpy, but
engineers can work with lumpy parts if they have smooth bearings to support
them. Conveniently enough, some bonds between atoms make fine bearings; a part
can be mounted by means of a single chemical
bond that will let it turn freely and smoothly. Since a bearing can
be made using only two atoms (and since moving parts need have only a few
atoms), nanomachines can indeed have mechanical components of molecular size.
How will these better machines be built? Over the years, engineers have used
technology to improve technology. They have used metal tools to shape metal
into better tools, and computers to design and program better computers. They
will likewise use protein nanomachines to build better nanomachines. Enzymes
show the way: they assemble large molecules by “grabbing” small
molecules from the water around them, then holding them together so that a bond
forms. Enzymes assemble DNA, RNA, proteins, fats, hormones, and chlorophyll in
this way – indeed, virtually the whole range of molecules found in living
things. Biochemical engineers, then, will construct new enzymes to assemble new
patterns of atoms. For example, they might make an enzyme-like machine which
will add carbon atoms to a small spot, layer on layer. If bonded correctly, the
atoms will build up to form a fine, flexible diamond fiber having
over fifty times as much strength as the same weight of aluminum. Aerospace
companies will line up to buy such fibers by the ton to make advanced
composites. (This shows one small reason why military competition will drive
molecular technology forward, as it has driven so many fields in the past.) But
the great advance will come when protein machines are able to make structures
more complex than mere fibers. These programmable protein machines will
resemble ribosomes programmed by RNA, or the older generation of automated
machine tools programmed by punched tapes. They will open a new world of
possibilities, letting engineers escape the limitations of proteins to build
rugged, compact machines with straightforward designs. Engineered proteins will
split and join molecules as enzymes do. Existing proteins bind a variety of
smaller molecules, using them as chemical tools; newly engineered proteins will
use all these tools and more. Further, organic chemists have shown that
chemical reactions can produce remarkable results even without nanomachines to
guide the molecules. Chemists have no direct control over the tumbling motions
of molecules in a liquid, and so the molecules are free to react in any way
they can, depending on how they bump together. Yet chemists nonetheless coax reacting molecules
to form regular structures such as cubic and dodecahedral molecules, and to
form unlikely-seeming structures such as molecular rings with highly strained
bonds. Molecular machines will have still greater versatility in bondmaking,
because they can use similar molecular motions to make bonds, but can guide
these motions in ways that chemists cannot. Indeed, because chemists cannot yet
direct molecular motions, they can seldom assemble complex molecules according
to specific plans. The largest molecules they can make with specific, complex
patterns are all linear chains. Chemists form these patterns (as in gene
machines) by adding molecules in sequence, one at a time, to a growing chain.
With only one possible bonding site per chain, they can be sure to add the next
piece in the right place. But if a rounded, lumpy molecule has (say) a hundred
hydrogen atoms on its surface, how can chemists split off just one particular
atom (the one five up and three across from the bump on the front) to add
something in its place? Stirring simple chemicals together will seldom do the
job, because small molecules can seldom select specific places to react with a
large molecule. But protein machines will be more choosy. A flexible,
programmable protein machine will grasp a large molecule (the workpiece) while
bringing a small molecule up against it in just the right place. Like an
enzyme, it will then bond the molecules together. By bonding molecule after
molecule to the workpiece, the machine will assemble a larger and larger
structure while keeping complete control of how its atoms are arranged. This is
the key ability that chemists have lacked. Like ribosomes, such nanomachines
can work under the direction of molecular tapes. Unlike ribosomes, they will
handle a wide variety of small molecules (not just amino acids) and will join
them to the workpiece anywhere desired, not just to the end of a chain. Protein
machines will thus combine the splitting and joining abilities of enzymes with
the programmability of ribosomes. But whereas ribosomes can build only the
loose folds of a protein, these protein machines will build small, solid
objects of metal, ceramic, or diamond – invisibly small, but rugged. Where our
fingers of flesh are likely to bruise or burn, we turn to steel tongs. Where
protein machines are likely to crush or disintegrate, we will turn to
nanomachines made of tougher stuff.
Universal
Assemblers
Перевод:
Современный человек едва ли может представить свою жизнь без машин. Ежедневно или появляются новые устройства, или улучшаются уже существующие. Люди по-разному относятся к новым изобретениям. Некоторые полагают, что сложные гаджеты на самом деле полезны и необходимо, в то время, как другие считают их ужасными из-за их отрицательного влияния на людей. Что касается меня, я абсолютно уверена в том, что новые устройства делают нашу жизнь легче.
Во-первых, они выполняют всю грязную и тяжелую работу, такую как уборка. Во-вторых, устройства экономят как время, так и место. Например, компьютерный диск может вмещать столько же информации, как несколько толстых книг. Итак, машины помогают людям в разных сферах деятельности.
Однако противники этой точки зрения абсолютно уверены в том, что новые изобретения отрицательно влияют на людей. Люди не хотят работать из-за влияния устройств. Они становятся ленивыми и неорганизованными. Они ждут, когда их последние изобретения сделают всё за них. Более того, по мнению ученых, многие широко распространенные гаджеты обладают излучением, которое может вызвать серьёзные проблемы со здоровьем. Кроме того, всё больше и больше людей становятся зависимыми от компьютера, телевизора или мобильного телефона. Они игнорируют свои домашние обязанности, учебу или работу и проводят всё своё время перед ноутбуком или экраном телевизора.
В заключение, я считаю, что, несмотря на все имеющиеся недостатки, достоинства гаджетов намного более занчительны, так как они экономят время и позволяют людям наслаждаться жизнью!
Каменская Татьяна
We live in the 21st century and we are surrounded by technology. Is it good or is it bad? Let’s think about it.
The first thing that springs to mind is technology is great. It makes our life easier in many ways. For instance we have a lot of kitchen appliances that help us cook, cut, and wash in less time than 20 years ago. So housing has become much less time consuming. It applies to many other areas of our life.
Technologies help us be connected. Most people have some kind of a smart phone that allows them to stay online, share their news with friends and relatives no matter where they are at the moment. Nowadays we have easy access to information, which help in education and business. There are numerous resources that give people opportunity to study at home or be accepted in a university abroad without leaving their home country.
Of course we need to mention technologies used in medicine. They help save lives or improve lives of those who suffered from accidents or were born with some abnormalities. Technologies help us travel in quicker ways. The list of advantages can go and on.
But does technology have disadvantages? It definitely does. The speed with which modern technologies develop and our attempts to catch up with it make our lives more stressful. We have become more isolated, as more and more people replace real relations with social media ones. We virtually don’t need to go out to satisfy our basic needs like food, medicine etc.
Technology definitely improves our lives but only when used in moderation.
Перевод:
Технологии в нашей жизни
Мы живем в XXI веке, и технологии нас окружают. Хорошо это или плохо? Давайте думать.
Первое, что приходит в голову, технологии – это прекрасно. Они упрощают нашу жизнь. Например, сейчас существует много бытовых приборов, которые помогают нам готовить, резать и мыть за меньшее время, чем 20 лет назад. Ведение домашнего хозяйства занимает теперь значительно меньше времени. И это справедливо для многих сфер нашей жизни.
Технологии помогают нам всегда оставаться на связи. У большинства теперь есть смартфон, с помощью которого они выходят в интернет, делятся новостями с друзьями и родственниками, где бы те ни находились. Сегодня очень просто получить доступ к нужной информации, что помогает как в обучении, так и в бизнесе. Существует множество ресурсов, позволяющих обучатся дома, есть возможность поступить в иностранный университет, не уезжая из родной страны.
Конечно, нужно отметить и технологии, используемые в медицине. Они помогают спасать жизни людей и улучшать качество жизни тех, кто пострадал в результате несчастного случая или родился с отклонениями. Технологии позволяют нам путешествовать, тратя все меньше времени. Список преимуществ, которые дают нам технологии, можно продолжать довольно долго.
Но есть ли какие-то недостатки? Определенно есть. Скорость, с которой сейчас развиваются технологии и наши попытки угнаться за прогрессом, наполняют нашу жизнь стрессом. Мы стали более одинокими, поскольку все больше и больше людей предпочитают реальным отношениям виртуальные. Нам в принципе можно не выходить из дома, чтобы удовлетворить базовые потребности в еде, лекарствах и т.д.
Технологии значительно улучшают нашу жизнь, если мы используем их разумно.
Автор — Дарья Царева
We live in the era of high technologies, and we use modern inventions in our everyday life because they have brought us much comfort. New technologies have spread on every field over the past 15 years. Moreover, they are rapidly changing. For example, video-recorders, DVD-players or compact disks have already become obsolete and have been replaced by more up-to-date devices. Today we can hardly imagine our life without such modern mobile devices as cell phones or laptops. Our offices are fully equipped with computers, printers, scanners, air-conditioners, interactive whiteboards and wi-fi modems. Household appliances (vacuum-cleaners, coffee-machines, dish-washers, food processors and others) help us to save our time and energy.
However, we should realize that digital and electronic inventions have both negative and positive impact on our daily life.
I am absolutely positive that new technologies or gadgets are making things faster, easier, more comfortable and interesting. For instance, if you install a GPS (Global Positioning System) in your car you’ll never get lost again. And could we imagine just 15 years ago all the things we can do on the wireless Internet nowadays: connecting with friends from all over the world, online shopping and banking, distance online learning, finding virtual relationships and even working from home? Isn’t that awesome?! Our parents used to go to post-offices to send letters or pay bills, they went to libraries to find a good book and they used telephone-booths for phone-calls.
On the other hand, I know some people who are strongly against some modern inventions because they really miss those days when they talked to each other face to face in reality, and not virtually. I partially agree with that as I really believe that people are becoming anti-social and too dependent on their gadgets. Some of my friends also spend half of the time occupying their shiny gadgets (smart-phones or i-pads) even when we go out together. Besides, people who use various social networks a lot (such as Facebook or Instagram) should worry more about their privacy.
Summing up, I could say that there are serious arguments both for and against the use of new technologies but anyway it’s really difficult to imagine our life without them today.
Новые технологии в нашей жизни
Мы живем в эпоху высоких технологий и пользуемся современными изобретениями в повседневной жизни, поскольку они принесли нам много комфорта. Новые технологии распространились в каждой области за последние 15 лет. Более того, они стремительно меняются. Например, видеомагнитофоны, DVD-плееры или компакт-диски стали уже устаревшими, и им на смену пришли более современные устройства. Сегодня мы с трудом можем представить нашу жизнь без таких современных мобильных приборов, как сотовые телефоны или ноутбуки. Наши офисы полностью оборудованы компьютерами, принтерами, сканерами, кондиционерами, интерактивными досками и wi-fi модемами. Бытовые приборы (пылесосы, кофе-машины, посудомоечные машины, кухонные комбайны и другие) помогают нам экономить время и энергию.
Однако, нам следует понимать, что цифровые и электронные изобретения имеют как отрицательное, так и положительное влияние на нашу повседневную жизнь.
Я полностью согласен с тем, что новые технологии или гаджеты делают многие вещи быстрее, легче, удобнее и интереснее. К примеру, если вы устанавливаете в своем автомобиле GPS (Глобальную Навигационную Систему), вы больше никогда не заблудитесь. А могли ли мы представить всего лишь 15 лет назад все то, что можем делать сегодня по беспроводному интернету: связь с друзьями по всему миру, онлайн покупки и банковские операции, дистанционное онлайн обучение, поиск виртуальных знакомств и даже работу из дома? Разве это не здорово?! Наши родители раньше отправлялись в почтовое отделение для того, чтобы отсылать письма или оплачивать счета, они ходили в библиотеки для того, чтобы найти хорошую книгу и пользовались телефонными будками для того, чтобы позвонить.
С другой стороны, я знаю людей, которые категорически против некоторых современных изобретений, так как им очень не хватает тех дней, когда они общались друг с другом, лицом к лицу в реальности, а не виртуально. Частично я согласен с этим, потому что я считаю, что люди становятся анти-социальными и слишком зависимыми от своих гаджетов. Некоторые мои друзья также посвящают половину времени своим блестящим гаджетам (смартфонам или ай-пэдам), даже когда мы выходим вместе погулять. Кроме того, людям, которые много пользуются социальными сетями (такими, как Фэйсбук или Инстарграм), нужно побеспокоиться о защите своей личной информации.
Подводя итог, я бы сказал, что существуют серьезные аргументы за и против использования новых технологий, но, в любом случае, в наши дни уже будет очень сложно представить жизнь без них.
The final ingredient to nanotechnology is the ability to characterize and predict nanoscale properties and behavior. New experimental tools that are able to “see”, “touch”, and measure the behavior of individual nanostrucures allow scientists and engineers to identify subtle differences in structure and properties that control nanoscale properties. By coupling new experimental techniques with advanced computational tools, researchers can develop, verify, and refine models and simulations that will allow the full potential for nanotechnology to be explored.
There has been much debate on the future implications of nanotechnology. Nanotechnology has the potential to create many new materials and devices with a vast range of applications, such as in medicine, electronics and energy production. On the other hand, nanotechnology raises many of the same issues as with any introduction of new technology, including concerns about the toxicity and environmental impact of nanomaterials, and their potential effects on global economics, as well as speculation about various doomsday scenarios. These concerns have led to a debate among advocacy groups and governments on whether special regulation of nanotechnology is warranted.
4. Compare two columns of words and find Russian equivalents (from the right column) to the following English words (from the left one):
1. На атомном и молекулярном уровне
a) to improve efficiencies of catalysts
2. иметь дело со структурами размеромв 100 миллимикронов
b) as the result of physical and chemical interaction
3. как результат химического и физического взаимодействия
c) on an atomic and molecular scale
4. изменять химические и физические свойства материалов
d) to deal with structures of the size 100 nanometers
5. улучшать эффективность катализаторов
e) to alter physical and chemical properties of materials
6. вырабатывать свет
f) to characterize and predict properties of nanostructures
7. превращать пластичные материалы в твердые
g) to generate light
8. исследовать весь потенциал нанотехнологии
h)to turn ductile materials into solids
9. характеризовать и предсказывать свойства наноструктур
i) effects of nanomaterials on global economics
10. действие наноматериалов на глобальную экономику
j) to explore the full potential of nanotechnology
11. широкий спектр применения наноматериалов
k) concerns about the toxicity of nanomaterials
12. беспокойства по поводу токсичности наноматериалов
l)a vast range of applications of nanomaterials
5. Say whether the following statements are true or false:
1) Nanotechnology is creating an entirely new class of materials and devices with unique and potentially very useful properties.
2) The physical dimensions of nanotechnology are small, spanning from just a few to tens of nanometers.
3) Nanotechnology is very diverse, ranging from extensions of conventional device physics to completely new approaches based upon molecular self-assembly, from developing new materials with dimensions on the nanoscale to investigating whether we can directly control matter on the atomic scale.
4) Nowadays current interest in nanotechnology is not high.
5) The field of nanotechnology is developing slowly as are its practical application.
6) Unique nanoscale properties are already being used to increase energy efficiency and improve healthcare.
6. Answer the following questions:
1) What is nanotechnology?
2) What does nanotechnology deal with?
3) Which properties do materials hundreds of nanometers in size exhibit?
4) What is the final ingredient to nanotechnology?
5) What is the application of nanotechnology?
Эссе
на тему «За» и «Против» нанотехнологии
как качественному переходу от манипуляции
веществом к манипуляции отдельными
атомами»
В
последние десятилетия существенное
внимание уделяется новому направлению
в естественных и технических науках –
нанонауке и нанотехнологии. Согласно
определению Национальной нанотехнологической
инициативы США [1], суть нанотехнологии
заключается в способности работать на
молекулярном уровне, атом за атомом,
создавая большие структуры с фундаментально
новой молекулярной организацией.
Нанотехнология имеет дело с материалами
и системами, структура и компоненты
которых демонстрируют новые и значительно
улучшенные физические, химические и
биологические свойства, явления и
процессы, обусловленные их нанометровым
размером.
Интерес
к нанотехнологии как принципиально
новому возможному методу получения
материалов методом «снизу – вверх»
(т.е. путем сборки материала из отдельных
атомов и молекул) проявился благодаря
выступлению американского физика
Ричарда Фейнмана «There’s Plenty of Room at the
Bottom» [2], в котором он рассмотрел возможность
манипулирования отдельными атомами
как процесс, не противоречащий законам
физики.
Позднее
к идеям конструирования вещества путем
его сборки из отдельных атомов обратился
американский физик и футуролог Эрик
Дрекслер. В 1986 г. вышла его книга «Машины
создания: пришествие эры нанотехнологии»,
в которой он рассмотрел принципы
молекулярной технологии – технологии
манипуляции отдельными атомами и
молекулами, а также молекулярные машины
(ассемблеры) – устройства нанометрового
размера, позволяющих конструировать
молекулы из отдельных атомов по заданному
принципу (аналогично молекулам ДНК в
биологических системах).
Идея
нанотехнологии как процесса манипулирования
отдельными атомами в том виде, в котором
ее представил Дрекслер, вызвала оживленные
споры и негативные отклики. С этической
точки зрения считалось, что разработка
и внедрение такой технологии повлечет
за собой создание новых молекулярных
форм, способных причинить вред всему
живому, выход из-под контроля
устройств-ассемблеров а также их
использования в качестве оружия массового
уничтожения.
Однако,
с точки зрения законов физики и здравого
смысла возможность создания наноассемблеров,
конструирующих молекулы из отдельных
атомов, не была подтверждена, и идеи
Дрекслера так и остались громким
футурологическим прогнозом. Впоследствии
свое предположение отверг и сам Дрекслер
[3].
Однако,
нанотехнология в широком смысле не
ограничивается лишь конструированием
вещества из отдельных атомов. Нанотехнологию
следует рассматривать как умение
целенаправленно создавать и использовать
материалы, устройства и системы, структура
которых регулируется в диапазоне
размеров приблизительно 1-100 нм. Материалы
в таком диапазоне размеров, благодаря
проявлению размерных эффектов, обладают
новыми свойствами, отличающимися от их
крупномасштабных аналогов. В настоящее
время разработано множество способов
применения наноматериалов в различных
областях химии, техники, медицины и т.д.
Использование наноматериалов зачастую
позволяет улучшить характеристики
традиционных материалов или заменить
их, а в некоторых случаях – создать
новые материалы, обладающие ранее
недоступными характеристиками. Данный
аспект применения наноматериалов и
технологий их получения несомненно
является весомым аргументом в поддержку
развития нанонауки и нанотехнологии.
Однако,
важно отметить, что размерные эффекты,
проявляемые в наноматериалах, могут
вызывать также неожиданные негативные
действия. Примером такого отрицательного
воздействия некоторых наноматериалов
является их высокая токсичность и
реакционоспособность. Противники
нанотехнологии в частности и
технологического прогресса в общем
рассматривают данный факт как аргумент
против нанотехнологии. Действительно,
они правы в том, что при разработке
нового материала или новой технологии
следует уделять внимание не только их
преимуществам, но и рассматривать
возможные опасности получаемого
материала или создаваемого метода.
Однако, данной позиции следует
придерживаться любому исследователю,
независимо от области его деятельности.
Список
используемых
источников:
1.
National Nanotechnology Initiative (NNI) http://www.nano.gov
2.
Feynman Richard P.: Classic talk that Richard Feynman gave on
December 29th 1959 at the annual meeting of the American Physical
Society at the California Institute of Technology (Caltech). «There’s
Plenty of Room at the Bottom».
http://en.academic.ru/dic.nsf/enwiki/14388
3.
Drexler K. Eric. Engines of Creation 2.0: The Coming Era of
Nanotechnolo-gy – Updated and Expanded. WOWIO
Books, 2007.
So, firstly, modern technologies give us much information about the world. Sitting at home we can learn all news and all details about any event. The use of modern technologies is one of the best ways to explore the world.
Secondly, thanks to modern technologies we can communicate with people, to write letters, to find new friends. It is a real pleasure. When you miss your family, you can call and see the people who are dear to you using Skype.
Thirdly, with the help of modern technologies we can gain different knowledge. We can study various subjects. We can learn everything. It simplifies our life. Modern technologies have a lot of pros, but they have some cons too. You should mind that they may damage your health. But, to my mind, they still have more pros than cons.
Thanks to the Internet you can do almost everything. You can watch movies, play games, make various projects, buy many things, read books, and do many others. Modern technologies help us to relax, for example, when we watch entertainment programs on TV, listen to music…Modern technologies are great helpers in our life. They help us in many ways and simplify our life.
Я хочу затронуть проблему современных технологиях. По моему мнению люди не могут жить без них. ТВ, телефоны, радио, интернет, электронные книги и многое другое все это очень полезные и важные вещи в нашей жизни.
Во первых современные технологии дают нам информацию обо всем мире. Сидя дома мы можем узнать все новости, все подробности любого события. Использование современных технологий один из лучших способов познания мира.
Во вторых мы можем общаться с людьми, писать им письма, находить новых друзей. Это реально круто. Когда ты скучаешь по семье ты можешь позвонить им и увидеть людей которые дороги тебе с помощью скайпа.
В третьих благодаря современным технологиям мы можем получать разнообразные знания. Можем изучать различные предметы. Научится всему. Это упрощает нашу жизнь. Современные технологии имеют много плюсов, но есть и минусы. Вы должны возражать6 что они могут вредить вашему здоровью. Но по моему мнению плюсов больше чем минусов.
Благодаря интернету возможно почти все. Можно смотреть фильмы, играть в игры, составлять различные проекты, делать покупки, читать книжки и многое другое. Современные технологии помогают нам отдыхать, например когда мы смотрим по телевизору развлекательные программы, слушаем музыку… Современные технологии большие помощники в нашей жизни. Они помогают нам во многих вещах и упрощают нашу жизнь
The impact of nanotechnology extends from its medical, ethical, mental, legal and environmental applications, to fields such as engineering, biology, chemistry, computing, materials science, and communications.Major benefits of nanotechnology include improved manufacturing methods, water purification systems, energy systems, physical enhancement, nanomedicine, better food production methods and nutrition and large scale infrastructure auto-fabrication.[vague] Nanotechnology’s reduced size may allow for automation of tasks which were previously inaccessible due to physical restrictions, which in turn may reduce labor, land, or maintenance requirements placed on humans.Potential risks include environmental, health, and safety issues; transitional effects such as displacement of traditional industries as the products of nanotechnology become dominant, which are of concern to privacy rights advocates. These may be particularly important if potential negative effects of nanoparticles are overlooked.Whether nanotechnology merits special government regulation is a controversial issue. Regulatory bodies such as the United States Environmental Protection Agency and the Health & Consumer Protection Directorate of the European Commission have started dealing with the potential risks of nanoparticles. The organic food sector has been the first to act with the regulated exclusion of engineered nanoparticles from certified organic produce, firstly in Australia and the UK,[1] and more recently in Canada, as well as for all food certified to Demeter International standards