EMERGENCE OF NANOTECHNOLOGY
Date: 2015-10-07; view: 449.
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Ex.5. Pronounce the words correctly:
nanotechnology, nanometer, colloidal, dispersion, metallic, catalysts, regime, nanoparticles, inorganic, ceramic, porcelain, stable, application, arthritis, to diagnose, spinal, explosion, to manipulate, nanoscale, fever, semiconductor, characterization, dimension, technique, molecular, nanoscaled, electronics, device, thermodynamics, challenge, design, transistor, metal-oxide, exponentially, dissipation, issue, shrinkage, wavelength, miniaturization, application, nanomedicine, therapy, diagnostics, nanorobots, vehicle, therapeutic, guardian, detector, to accommodate, functionality, heterojunction, bipolar, synthetic, carbon, fullerenes.
Ex.6. Read and translate the following text into Russian. Divide it into logical parts. Entitle each of these parts:
TEXT
Nanotechnology is new, but research on nanometer scale is not new at all. The study of biological systems and the engineering of many materials such as colloidal dispersions, metallic quantum dots, and catalysts have been in the nanometer regime for centuries. For example, it's well known that the Chinese used Au nanoparticles as an inorganic dye to introduce red color into their ceramic porcelains more than thousand years ago. Use of colloidal gold has a long history, though a comprehensive study on the preparation and properties of colloidal gold was first published in the middle of the 19th century. Colloidal dispersion of gold prepared by Faraday in 1857 was stable for almost a century before being destroyed during World War II.Medical applications of colloidal gold present another example. Colloidal gold was, and is still, used for treatment of arthritis. A number of diseases were diagnosed by the interaction of colloidal gold with spinal fluids obtained from the patient. What has changed recently is an explosion in our ability to image, engineer and manipulate systems in the nanometer scale. What is really new about nanotechnology is the combination of our ability to see and manipulate matter on the nanoscale and our understanding of atomic scale interactions.
Although study on materials in the nanometer scale can be traced back for centuries, the current fever of nanotechnology is at least partly driven by the ever shrinking of devices in the semiconductor industry and supported by the availability of characterization and manipulation techniques at the nanometer level. The continued decrease in device dimensions has followed the well-known Moore's law predicted in 1965.
Many scientists are currently working on molecular and nanoscaled electronics, which are constructed using single molecules or molecular mono layers. Although the current devices operate far below fundamental limits imposed by thermodynamics and quantum mechanic, a number of challenges in transistor design have already arisen from materials limitations and device physics. For example, the off-currents in a metal-oxide semiconductor field-effect transistor (MOSFET) increase exponentially with device scaling. Power dissipation and overheating of chips have also become a serious issue in further reduction of device sizes. The continued size shrinkage of transistors will sooner or later meet with the limitations of the materials' fundamentals. For example, the widening of the band gap of semiconductors occurs when the size of the materials reaches de Broglie's wavelength.
Miniaturization is not necessarily limited to semiconductor-based electronics, though simple miniaturization already brings us significant excitement. Promising applications of nanotechnology in the practice of medicine, often referred to as nanomedicine, have attracted a lot of attention and have become a fast growing field. One of the attractive applications in nanomedicine is the creation of nanoscale devices for improved therapy and diagnostics. Such nanoscale devices are known as nanorobots or more simply as nanobots. These nanobots have the potential to serve as vehicles for delivery of therapeutic agents, detectors or guardians against early disease and perhaps repair of metabolic or genetic defects. Studies in nanotechnology are not limited to miniaturization of devices. Materials in nanometer scale may exhibit unique physical properties and have been explored for various applications. For example, gold nanoparticles have found many potential applications using surface chemistry and its uniform size. Au nanoparticles can function as carrier vehicles to accommodate multiple functionalities through attaching various functional organic molecules or bio-components. Bandgap engineered quantum devices, such as lasers and heterojunction bipolar transistors, have been developed with unusual electronic transport and optical effects. The discovery of synthetic materials, such as carbon fullerenes, carbon nanotubes, and ordered mesoporous materials, has further fueled the research in nanotechnology and nanomaterials.
Ex.7. Answer the following questions:
a) How old is the research in the nanometer regime?
b) What did the Chinese use Au nanoparticles for?
c) Does use of colloidal gold or silver have a long history?
d) A comprehensive study on the preparation and properties of colloidal gold began in the middle of the 19th century, didn't it?
e) Who prepared colloidal dispersion of gold in 1857?
f) What has been the reason of the current fever of nanotechnology?
g) A number of challenges in transistor design have already arisen from materials limitations and device physics, haven't they?
a) Doctors widely use the means of nanotechnology, don't they?
b) What is one of the attractive applications in nanomedicine?
c) What way can people use nanobots in medicine?
d) May materials in nanometer scale exhibit unique physical properties?
e) Au nanoparticles can function as carrier vehicles to accommodate multiple functionalities, can't they?
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