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第二篇 Electric Backpack Backpacks are convenient. They can hold your books, your lunch, and a change of clothes, leaving your hands free to do other things. Someday, if you don’t mind carrying a heavy load, your backpacks might also power your MF3 player, keep your cell phone running, and maybe even light your way home. Lawrence C. Rome and his colleagues from the University of Pennsylvania in Philadelphia and the Marine Biological Laboratory in Woods Hole, Mass., have invented a backpack that makes electricity from energy produced while its wearer walks. In military actions, search-and-rescue operations, and scientific field studies, people rely increasingly on cell phones, global positioning system (GPS) receivers, night-vision goggles, and other battery-powered devices to get around and do their work. The backpack’s electricity-generating feature could dramatically reduce the amount of a wearer’s load now devoted to spare batteries, report Rome and his colleagues in the Sept. 9 Science. The backpack’s electricity-creating powers depend on springs used to hang a cloth pack from its metal frame. The frame sits against the wearer’s back, and the whole pack moves up and down as the person walks. A gear mechanism converts vertical movements of the pack to rotary motions of an electrical generator, producing up to 7.4 watts. Unexpectedly, tests showed that wearers of the new backpack alter their gaits in response to the pack’s oscillations, so that they carry loads more comfortably and with less effort than they do ordinary backpacks. Because of that surprising advantage, Rome plans to commercialize both electric and non-electric versions of the backpack. The backpack could be especially useful for soldiers, scientists, mountaineers, and emergency workers who typically carry heavy backpacks. For the rest of us, power-generating backpacks could make it possible to walk, play video games, watch TV, and listen to music, all at the same lime. Electricity-generating packs aren’t on the market yet, but if you do get one eventually, just make sure to look both ways before crossing the street! According to Paragraph 4. what does Rome plan to do
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阅读下面这篇短文，短文后列出7个句子，请根据短文的内容对每个句子做出判断。 Inventor of LED When Nick Holonyak set out to create a new kind of visible lighting using semiconductor alloys, his colleagues thought he was unrealistic. Today, his discovery of light-emitting diodes, or LEDs, are used in everything from DVDs to alarm clocks to airports. Dozens of his students have continued his work, developing lighting used in traffic lights and other everyday technology. On April 23, 2004, Holonyak received the $,500,000 Lemelson-MIT Prize at a ceremony in Washington. This marks the 10th year that the Lemelson-MIT Program at the Massachusetts Institute of Technology (MIT) has given the award to prominent inventors. "Anytime you get an award, big or little, it’s always a surprise," Holonyak said. Holonyak, 75, was a student of John Bardeen, an inventor of the transistor, in the early 1950s. After graduate school, Holonyak worked at Bell Labs. He later went to General Electric, where he invented a switch now widely used in house dimmer switches. Later, Holonyak started looking into how semiconductors could be used to generate light. But while his colleagues were looking at how to generate invisible light, he wanted to generate visible light. The LEDs he invented in 1962 now last about 10 times longer than incandescent bulbs, and are more environmentally friendly and cost effective. Holonyak, now a professor of electrical and computer engineering and physics at the University of Illinois, said he suspected that LEDs would become as commonplace as they are today, but didn’t realize how many uses they would have. "You don’t know in the beginning. You think you’re doing something important, you think it’s worth doing, but you really can’t tell what the big payoff is going to be, and when, and how. You just don’t know," he said. The Lemelson-MIT Program also recognized Edith Flanigen, 75, with the $100,000 Lemelson-MIT Lifetime Achievement Award for her work on a new generation of "molecular sieves," that can separate molecules by size. Holonyak believed that LEDs would become very popular in the future.
下面有3篇短文，每篇短文后有5道题，每题后面有4个选项。请仔细阅读短文并根据短文回答其后面的问题，从4个选项中选择1个最佳答案。第一篇 Ford Abandons Electric Vehicles The Ford motor company’s abandonment of electric cars effectively signals the end of the road for the technology, analysts say. General Motors and Honda ceased production of battery-powered cars in 1999, to focus on fuel cell and hybrid electric gasoline engines, which are more attractive to the consumer. Ford has now announced it will do the same. Three years ago, the company introduced the Think City two-seater car and a golf cart called the THINK, or Think Neighbor It hoped to sell 5,000 cars each year and 10,000 carts. But a lack of demand means only about 1,000 of the cars have been produced, and less than 1,700 carts have been sold so far in 2002. "The bottom line is we don’t believe that this is the future of environment transport for the mass market," Tim Holmes of Ford Europe said on Friday. "We feel we have given electric our best shot." The Think City has a range of only about 55 miles and up to a six-hour battery recharge time. General Motors’ EVI electric vehicle also had a limited range, of about 100 miles. The very expensive batteries also mean electric cars cost much more than petrol-powered alternatives. An electric Toyota RAV4 EV vehicle costs over $42,000 in the US, compared with just $17,000 for the petrol version. Toyota and Nissan are, now the only major auto manufacturers to produce electric vehicles. "There is a feeling that battery electric has been given its chance. Ford now has to move on with its hybrid program, and that is what we will be judging them on," Roger Higman, a senior transport campaigner at UK Friends of the Earth, told the Environment News Service. Hybrid cars introduced by Toyota and Honda in the past few years have sold well. Hybrid engines offer greater mileage than petrol-only engines, and the batteries recharge themselves. Ford says it thinks such vehicles will help it meet planned new guidelines on vehicle emissions in the US. However, it is not yet clear exactly what those guidelines will permit. In June, General Motors and Daimler Chrysler won a court injunction, delaying by two years Californian legislation requiring car-makers to offer 100,000 zero-emission and other low-emission vehicles in the state by 2003. Car manufacturers hope the legislation will be rewritten to allow for more low-emission, rather than zero-emission, vehicles. According to the eighth paragraph, hybrid cars
阅读下面的短文，文中有15处空白，每处空白给出了4个选项，请根据短文的内容从4个选项中选择1个最佳答案。 Captain Cook Arrow Legend It was a great legend while it lasted, but DNA testing has (51) ended a two-century-old story of the Hawaiian arrow carved from the bone of British explorer Captain James Cook (52) died in the Sandwich Islands in 1779. "There is (53) Cook in the Australian Museum," museum collection manager Jude Philip said not long ago in announcing the DNA evidence that the arrow was not made of Cook’s bone. But that will not stop the museum from continuing to display the arrow in its (54) "Uncovered: Treasures of the Australian Museum," which (55) include a feather cape presented to Cook by Hawaiian King Kalani ’opu’u in 1778. Cook was one of Britain’s great explorers and is credited with (56) the "Great South Land," (57) Australia, in 1770. He was clubbed to death in the Sandwich Islands, now Hawaii. The legend of Cook’s arrow began in 1824 (58) Hawah’an King Kamehameha on his. deathbed gave the arrow m William Adams, a London surgeon and relative of Cook’s wife, saying it was made of Cook’s bone after the fatal (59) with islanders. In the 1890s the arrow was given to the Australian Museum and the legend continued (60) it came face-to-face with science. DNA testing by laboratories in Australia and New Zealand revealed the arrow was not made of Cook’s bone but was more (61) made of animal bone, said Philp. However, Cook’s fans (62) to give up hope that one Cook legend will prove true and that part of his remains will still be uncovered, as they say there is evidence not all of Cook’s body was (63) at sea in 1779. "On this occasion technology has won," said Cliff Thornton, president of the Captain Cook Society, in a (64) from Britain. "But I am (65) that one of these days ...one of the Cook legends will prove to be true and it will happen one day."
阅读下面这篇短文，短文后列出7个句子，请根据短文的内容对每个句子做出判断。 Inventor of LED When Nick Holonyak set out to create a new kind of visible lighting using semiconductor alloys, his colleagues thought he was unrealistic. Today, his discovery of light-emitting diodes, or LEDs, are used in everything from DVDs to alarm clocks to airports. Dozens of his students have continued his work, developing lighting used in traffic lights and other everyday technology. On April 23, 2004, Holonyak received the $,500,000 Lemelson-MIT Prize at a ceremony in Washington. This marks the 10th year that the Lemelson-MIT Program at the Massachusetts Institute of Technology (MIT) has given the award to prominent inventors. "Anytime you get an award, big or little, it’s always a surprise," Holonyak said. Holonyak, 75, was a student of John Bardeen, an inventor of the transistor, in the early 1950s. After graduate school, Holonyak worked at Bell Labs. He later went to General Electric, where he invented a switch now widely used in house dimmer switches. Later, Holonyak started looking into how semiconductors could be used to generate light. But while his colleagues were looking at how to generate invisible light, he wanted to generate visible light. The LEDs he invented in 1962 now last about 10 times longer than incandescent bulbs, and are more environmentally friendly and cost effective. Holonyak, now a professor of electrical and computer engineering and physics at the University of Illinois, said he suspected that LEDs would become as commonplace as they are today, but didn’t realize how many uses they would have. "You don’t know in the beginning. You think you’re doing something important, you think it’s worth doing, but you really can’t tell what the big payoff is going to be, and when, and how. You just don’t know," he said. The Lemelson-MIT Program also recognized Edith Flanigen, 75, with the $100,000 Lemelson-MIT Lifetime Achievement Award for her work on a new generation of "molecular sieves," that can separate molecules by size. Holonyak said that you should not do anything you are not interested in.
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