1、1. 为此,必须对电路(circuit)的基本内容有一个很好的了解。2. 这个系数(coefficient)有待确定。3. 现有的教科书均没有提这一点。4. 由于反馈(feedback)在电子线路(electronic circuit)中起着重要作用,所以对它的研究极为重要。5. 有迹象表明,计算机的价格将进一步下跌。6. 这个方法的确管用,不过到底该在什么情况下使用它尚不清楚。7. 十年前该厂的产量比现在高五倍。8. 激光(laser)是二十世纪六十年代引入的一项新技术,它能穿透(pierce)特别硬的物质。9. 为使晶体管(transistor)正常工作,必须给其电极(electrode)
2、加(apply)上合适的电压(voltage)。10. 代表磁场(magnetic field)的磁力线(magnetic line of force)是一些围绕该导线的同心圆(concentric circle)。11. 我们所谓的机器人(robot)实际上是能为人类做工的一种工具。12. 这类天线(antenna)和那类天线相比的优点是结构简单,效率高。13. 半导体(semiconductor)对光和热都很敏感(sensitive),这两者都对导电率(conductivity)影响很大。14. 只有通过对系统性能进行研究我们才能了解其优缺点。15. 本书既讲了实际的设计方法,同时也讲述了
3、理论问题,而重点放在一般概念上。Part two: Mistakes Correction(30%)(Write down the corrected sentence on the answer sheet. )1. We are easy to determine the effect of new drug to patient.2. The direction of an electric current was decided before electrons were not discovered.3. Sound travel much less faster than ligh
4、t is.4. The price for this instrument is expensive.5. There are a few exceptions for this rule.6. The hotter the body will be, the more it radiates energy.7. The feature of this device is small in size and light in weight.8. That professor is very interesting in this topic.9. Our semiconductor indus
5、try comes into being at the end of 1950s.10. The both engineers are busy to design a type of new computer.11. Work equals to force multiplying distance.12. The new design instrument is in good quality.13. The ability for some elements to give off radiations is referred as the radioactivity.Part thre
6、e: Read this article, translate the underlined sentences(15%), answer the questions (15%)and then summarize this article within 100 words (10%).The Dazzle of Lasers(激光)The acronym(首字母缩写词) laser, describes how the device works: Light Amplification by Stimulated Emission of Radiation. In 1916 Einstein
7、 predicted that electrons(电子) in an atom could be deliberately stimulated to emit photons(光子) (light energy) of a certain wavelength. He was right. The laser must first be pumped with energy in a variety of ways so that the electrons are excited into higher energy states. But these high energy elect
8、rons are unstable-and fall back to a lower energy level. On the way down, their extra energy is released(释放) as light. That light is captured inside the laser and amplified by bouncing it back and forth between mirrors. The laser beam that emerges is amplified, monochromatic(单色的), coherent light -an
9、d it shines with an unearthly power.Not until 1960 did Theodore Maiman, a 33-year-old engineer at Hughes Research Laboratories, build a homely four-inch cylinder containing a ruby rod encircled by a flash tube: the worlds first working laser.More than two decades later, the laser has wrought a techn
10、ological revolution. Lasers are an indispensable tool for delicate eye surgery, and doctors are using lasers experimentally to destroy cancerous tumors(肿瘤), unclog(使畅通) diseased arteries(动脉) and even treat herpes(疱疹). Just as they provide new tools for health care, however, they also make possible n
11、ew engines of destruction: recently Dr. Edward Teller, the father of the hydrogen bomb(氢弹), called on President Reagon to urge that the United States build a space-based laser-weapon system that would use a nuclear bomb to fire brutally intense laser X-rays against enemy missiles in flight.Today pil
12、ots flying the new Boeing 767 and 757 aircraft navigate with the aid of new laser gyroscopes(陀螺仪). Supermarket clerks use lasers to ring up prices at the checkout counter by reading universal bar-codes(条形码) printed on packages and canned goods. Powerful lasers cut and weld(焊) steel in factories from
13、 Detroit to Tokyo. Artists and filmmakers are beginning to use lasers for animation(动画): at Lucasfilm, George Lucas has a team of computer wizards(奇才) developing a machine that uses a computer-driven laser to draw animated images on film; a second film, with human actors, is then merged by laser wit
14、h the graphics into a single seamless(无缝的) whole.How does the laser work? Anyone who has ever focused sunlight through a magnifying glass and watched paper or dry leaves snap into flames understands the power of concentrated light. Laser light is intense, concentrated light, too, but it works on a d
15、ifferent principle. Shine sunlight through a prism(棱镜) and it breaks into the glorious colors of the rainbow. In the scientists vocabulary, sunlight is incoherent -it is made up of a mix of wavelengths spanning the spectrum(光谱) from infrared(红外线) to ultraviolet(紫外线). Laser light, on the other hand,
16、is monochromatic and coherentit shines at a single wavelength, and all the light waves march together in step like soldiers on parade(游行).In the two decades since its invention, the laser has undergone a dramatic transformation: a wide variety of gas, solid-state, diode(二极管) and other lasers has bee
17、n created. Each shines at a different wavelength; some pulse on and off, others operate continuously. When the laser moved out of the laboratory, one of its first and most significant applications was as a medical tool. Lasers are commonly used for delicate surgery inside the eye. In treating blood-
18、vessel disorders resulting from complications(并发症) of diabetes(糖尿病), doctors aim a fine beam of argon laser light(氩激光) through the pupil(瞳孔) of the eye and place up to 2000 tiny laser burns very closely around the back portion of the retina(视网膜). These laser welds prevent harmful growth or rupture(断
19、裂) of new, unwanted blood vessels. The very properties that make lasers dangerous -power and heat-are also being put to use to destroy some kinds of brain and spinal(脊髓的) tumors. Lasers have brought a new frontier to neurosurgery(神经外科). They have made some inoperable tumors operable and high-risk tu
20、mors less high risk. Warfare is also changing as laser technology advances. Laser guidance systems have brought once unimaginable accuracy to artillery(炮). In the near future, higher-intensity lasers may be used to blind the electronic sensory systems of aircraft, missiles, tanks and ships. And ulti
21、mately, some visionaries insists, the globe could be surrounded by a platoon(排) of orbiting battle stations armed with lasers capable of destroying planes and missiles within seconds of their being launched.Just as they are opening new doors to medicine and military practices, lasers are also having
22、 a profound impact on communications. Instead of sunbeams, todays light-wave communication systems use laser light ricocheting through tiny glass fibers. Lasers generate light waves at extraordinarily high frequencies-in the range of trillions of cycles per second -which makes it possible to transmi
23、t enormous quantities of information. In addition, fiber-optic cables are cheaper than copper wire and are not subject to electromagnetic interference, or the annoying cross talk(串话) and static that plague(折磨) current systems. The big breakthrough was the semiconductor laser.Someday laser light may
24、be piped through giant optic cables into deep ocean waters to create undersea farms; it may be beamed into space to talk to orbiting space stations. Lasers also may be used to fire extremely precise light pulses at DNA molecules, altering the structure of chromosomes(染色体) and thereby repairing defec
25、tive genes -or even creating new forms of life. And eventually billions of lasers will link the world in a vast information network, a global village of light.1. How does the laser work?2. What is the difference between sunlight and the laser?3. Is the laser absolutely safe? If not, please explain.4
26、. What are the advantages of the semiconductor laser in the communications field?5. In what fields is the laser applied?KEY:1. For this purpose, it is necessary to have a good understanding of the fundamentals of the circuit.2. This coefficient remains to be determined.3. None of the textbook availa
27、ble mentions this point.4. Since feedback plays an important role in the electronic circuit, its study is very important.5. There is an indication that the price of computers will fall further.6. This method does work, but it is not clear in what condition it is that it should be used.7. The output
28、of this factory 10 years ago is 6 times what it is now.8. A new technology introduced in the 1960s, laser can pierce very hard substances.9. For the transistor to work normally, it is necessary to apply a proper voltage across the electrode.10. The magnetic lines of force representing the magnetic f
29、ield are some concentric circles surrounding the wire.11. What is called a robot is a tool which can do work for the human being.12. This type of antenna has the advantages over that one of simple structure and high efficiency.13. Semiconductors are sensitive to light and hear, both of which have a
30、great impact on conductivity.14. Only through a study of the systems performance is it possible to know its advantages and disadvantages.15. This book discusses both practical design method and theoretical problems with emphasis on the basic concept.1. It is easy to determine the effect of the new d
31、rug on the patient.2. The direction of the electric current had been decided before electrons were discovered.3. Sound travels much more slowly that light does.4. This instrument is expensive.5. There are a few exceptions to this rule.6. The hotter the body is, the more energy it radiates.7. This device is small and light.8. That professor is much interested in this topic.9. Our semiconductor industry came into being at the end of the 1950s.10. Both the engineers are busy designing a new type of computer.11. Work equals force multiplied by distance.12. The newly designed instrume
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