[外语类试卷]大学英语六级模拟试卷375及答案与解析.doc
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1、大学英语六级模拟试卷 375及答案与解析 一、 Part I Writing (30 minutes) 1 Directions: For this part, you are allowed 30 minutes to write a resume. You should write at least 150 words following the outline given below: 假设你是李明 一名应届毕业生,在报纸上看到一则招聘广告,你想要到登广告的公司供职,请给该公司写一封求职信 ,内容应简要介绍自己的情况以及自己的经历等。 二、 Part II Reading Compreh
2、ension (Skimming and Scanning) (15 minutes) Directions: In this part, you will have 15 minutes to go over the passage quickly and answer the questions attached to the passage. For questions 1-4, mark: Y (for YES) if the statement agrees with the information given in the passage; N (for NO) if the st
3、atement contradicts the information given in the passage; NG (for NOT GIVEN) if the information is not given in the passage. 1 The Wonderful World of Small Theres a quiet revolution going on, and its name is nanotechnology. A host of innovations are coming our way. Some seem almost magical, like the
4、 new material created in 2004 by Ray Baughman, a professor at the University of Texas. Its stronger than steel, transparent, very, very light. A hectare-size sheet would weigh just 280 grams. When the professor announced that he hadnt decided what to call it, he started to get emails from around the
5、 world suggesting names. Since it was so light and strong, people started calling it “mithril“ the name of a highly prized type of armor used in The Lord of Rings. There are other discoveries too perhaps not so astounding, but practical and pleasant. Now there are socks that dont get smelly, pants t
6、hat resist stains, windows that repel dirt and toilets that clean themselves. All this results from exploring the world of the very, very small. Nano comes from the Greek word from dwarf. Usually nanotechnology is defined as the study and manipulation of matter smaller than 100 nanometers (纳米 ) that
7、s the scale of things like molecules and viruses. Ten hydrogen atoms pressed together against each other are just one nanometer long. And one million nanometers fit into a millimeter. Hard to grasp? Think of it this way: If everyone in Manila were a nanometer wide, the entire population, standing sh
8、oulder to shoulder, would fit on your thumbnail. Stunning Uses of Nanotechnology Like Alice in Wonderland, researchers in Nanoland find themselves in a world where old rules dont apply. Small things behave differently. This is behind several innovations, including the self-cleaning toilet. The toile
9、t bowl is sealed with a super-smooth glaze (涂层 ) that has microscopic holes under 30 nanometers. Because theyre smaller than bacteria or other tiny particles, theres not enough room for dirt to get stuck in the surface. Flushing is basically all the work you have to do. Researchers in Nanoland are a
10、lso making really, really small things with astonishing properties like the carbon nanotube. Chris Papadopoulos of the University of Victoria, says, “The carbon nanotube is the poster boy for nanotechnology.“ In your pencil, carbon, in the form of graphite (石墨 ), is soft and easily broken. But a car
11、bon nanotube is tough as nails much tougher in fact. Its very thin sheet graphite thats formed into a tube. These tiny straw-like cylinders, which can be as small as half a nanometer wide, are up to 100 times stronger than steel and six times lighter. They are the hardest, stiffest, strongest materi
12、als known and are among the worlds best conductors of heat and electricity. They can carry some 1,000 times more electricity current than copper wire: Everybody wants them, but until now theyve been in short supply and pricey. The current annual production, worldwide, is only 300 kilograms. At 860 a
13、 gram, carbon nanotubes cost 50 times more than gold. When it comes to finding uses for carbon nanotubes, the range is huge. The National Research Council Canada (NRC) is looking at harnessing their strength by embedding them in construction materials, among other applications. The Boeing Company th
14、inks nanotubes may be the source of futute improvements for high-performance aircraft. Some of the most stunning uses come out of Ray Baughmans research. Employing what he calls the “ancient technology of spinning“, Baughrnan and his team developed a way of spinning carbon nanotubes into fibers that
15、 are four times tougher than spider silk, the toughest natural filament (细丝 ). Since they also conduct electricity, the futuristic yarns could be woven into “smart“ clothing that stores electricity, is potentially bulletproof and incorporates sensors capable of adjusting the temperature of garment.
16、The fibers could also be made into cables for suspension bridges much longer than any we have now. And then there are Baughmans superstrong, superlight sheets. Papadopoulos explains that one of the reasons scientists are oxcited by the sheets is that they would make ideal solar sails. He says, “With
17、 a solar sail, you are allowing the pressure of the suns light to propel you through space the same way wind powers a sailboat.“ But there is also something in this for the earthbound traveler. Using an ordinary microwave oven, Baughmans team was able to weld one of his sheets between two pieces of
18、plexiglass (树脂玻璃 ). Afterwards, it still conducted electricity and remained transparent. One idea, therefore, is to put these sheets in windshields of the car and run current through them to defrost car windows. Medicine and Nanotechnology Many disease-causing bacteria and viruses are nano size. So
19、only nanotechnology would offer us ways of fighting back. Nucryst Pharmaceuticals has come up with a winning formula that combines nanoscience with old-fashioned folk wisdom. The ancient Greeks used silver to promote healing and prevent infection, but the treatment took a back seat when antibiotics
20、came on the scene. Nucryst has revived and improved on the old cure by coating a burn-and-wound bandage with nano-size silver particles that are more reactive than the bulk form of metal. They penetrate into the skin and work steadily. As a result, burn victims can have their dressings changed as li
21、ttle as once a week. Before Nucryst, such dressings had to be changed several times a day, a painful procedure that involved removing a healing cream. In 2004, Nucryst produced over three million bandages, and its sales topped 30 million. 70% of chronic-wound patients who were not healing at the exp
22、ected rate got better with the use of these bandages. Copy Nature with Nanoteehnology With new instruments that reveal natural structures down to the last atom, nanotechnologists ability to copy nature has taken off. When Bharat Bhushan, a mechanical engineering professor at Ohio State University, w
23、anted to make a super-smooth surface, he decided to copy lotus leaves. Scientists have long known that the leaves shed water very well: Theyre waxy and covered with tiny nano-size bumps, so water rolls off. Bhushan succeeded in making a polymer (聚合体 ) sheet that was equally smooth. “If you applied i
24、t to glass, you could have windows that dont need washing.“ says Bhushan. Hicham Fenniri, a chemistry professor at the Univeristy of Alberta, took a similar tack to make artificial joints act more like natural ones. The body recognizes an artificial hip or knee as foreign and may reject it. In most
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