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下面的短文有15处空白，请根据短文内容为每处空白白确定1个最佳选项。 It sounds all wrong-drilling holes in a piece of wood to make it more resistant to knock. But it works because the energy from the blow gets distributed throughout the wood rather than focusing on one weak spot. The discovery should lead to more effective and lighter packaging materials. Carpenters have known (51) centuries that some woods are tougher than others. Hickory(山核桃木), for example, was turned into axe handles and cartwheel spokes (车轮辐条) because it can absorb shocks without breaking. White oak (橡木), for example, is much more easily damaged, (52) it is almost as dense. Julian Vincent at Bathe University and his team were convinced the wood’s internal structure could explain the differences. Many trees have tubular(管状的) vessels that run (53) the trunk and carry water to the leaves. In oak they are large, and arranged in narrow bands, but in hickory they are smaller, and more evenly distributed. The researchers (54) this layout might distribute a blow’s energy throughout the wood, soaking up a bigger hit. To test the idea, they drilled holes 0.65 millimeters across into a block of spruce(云杉), a wood with (55) vessels, and found that (56) withstood a harder knock. (57) when there were more than about 30 holes per square centimeter did the wood’s performance drop off. A uniform substance doesn’t cope well with knocks because only a small proportion of the material is actually (58) . All the energy from the blow goes towards breaking the material in one or two places, but often the pieces left (59) are pristine(未经破坏的). "But instead of the energy being concentrated in one place, the holes provide many weak spots that all absorb energy as they break", says Vincent, "You are controlling the places (60) the wood breaks, and it can then absorb more (61) , more safely". The researchers believe the principle could be applied to any material- (62) example, to manufacture lighter and more protective packaging. That could (63) be used in car bumpers (保险杠), crash barriers and armor for military vehicles, says Ulrike Wegst, (64) the Max Plank Institute for Mental Research in Stuttgart. But she emphasizes that you’d (65) to design the substance with the direction of force in mind. "The direction of loading is crucial", she says.
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阅读下列材料 材料一： 没收一切私人的或团体的——豪绅、地主、祠堂、庙宇、会社、富农——田地、山林、池塘、房屋，归苏维埃政府公有，分配给无地、少地的农民及其他需要的贫农使用。 ——引自中共1930年《苏维埃土地法》 材料二： 1931年2月，毛泽东按中央决定指示各级政府发一布告：“说明过去分好了的田，(实行抽多补少，抽肥补瘦)，即算分定，得田的人，即由他管所分得的田，这田由他私有，别人不得侵犯。…‘租借买卖，由他自主；田中生产，除交土地税于政府外，均归农民所有。”——转引自胡绳主编《中国共产党的七十年》 材料三： 一方面要规定地主应该普遍地减租减息，不得抗不实行。另一方面，又要规定农民有交租交息的义务．不得抗不交纳。——引自中共中央1942年《关于抗日根据地土地问题》 材料四： 一切地主的土地及公地，由乡村农会接收，连同乡村其他一切土地，按乡村全部人口，不分男女老幼，统一平均分配……并归个人所有……承认其自由经营、买卖及在特定条件下出租的权利。 ——引自1947年《中国土地法大纲》 请回答： 材料四与材料一、二之间有什么联系说明了什么
第二篇 Oceanography Oceanography has been defined as "the application of all sciences to the study of the sea. " Before the nineteenth century, scientists with an interest in the sea were few. Certainly Newton considered some theoretical aspects of it in his writings, but he was reluctant to go to sea to farther his work. For most people the sea was remote, and with the exception of early intercontinental (大陆间的 ) travelers or others who earned a living from the sea, there was little reason to ask many questions about it, let alone to ask what lay beneath the surface. The first time that the question-" what is at the bottom of the oceans" had to be answered with any commercial consequence was when the laying of a telegraph cable from Europe to America was proposed. The engineers had to know the depth profile(起伏形状)of the route to estimate the length of cable that had to be manufactured. It was to Maury of the LIS Navy that the Atlantic Telegraph Company turned, in 1853, for information on this matter. In the 1840s, Maury had been responsible for encouraging voyages during which soundings(测水深) were taken to investigate the depths of the North Atlantic and Pacific Oceans. Later, some of his findings aroused much. popular interest in his book "The Physical Geography of the Sea". The cable was laid, but not until 1866 was the connection made permanent and reliable. At the early attempts, the cable failed and when it was taken out for repairing it was found to be covered with living creatures, a fact which defied contemporary scientific opinion that there was no life in the deeper parts of the sea. Within a few years oceanography was under way. In 1872, Thomson led a scientific expedition (考察), which lasted for four years and brought home thousands of samples from the sea. Their classification and analysis occupied scientists for years and led to a five-volume report, the last volume being published in 1895. We can infer from the passage that the telegraph cable was built mainly for______.
史量才，(中共七大，国民党六大)
第三篇 Live with Computer After too long on the net, even a phone call can be a shock. My boyfriend’s Liverpudlian (利物浦的) accent suddenly becomes indecipherable (难懂的)after the clarity of his words on screen; a secretary’s tone seems more rejecting than I’d imagined it would be. Time itself becomes fluid- hours become minutes, and alternately seconds stretch into days. Weekends, once a highlight of my week, are now just two ordinary days. For the latest three years, since I stopped working as a producer for Charlie Rose, I have done much of my work as a telecommuter. I submit articles and edit them via E-mail and communicate with colleagues on Internet mailing lists. My boyfriend lives in England ; so much of our relationship is computer-mediated. If I desired, I could stay inside for weeks without wanting anything. I can order food, and manage my money, love and work. In fact, at times I have spent as long as three weeks alone at home, going out only to get mail and buy newspapers and groceries. I watched most of the blizzard of 1996 on TV. But after a while, life itself begins to feel unreal. I start to feel as though I’ve merged with my machines, taking data in, spitting them back, just another node on the net. Others on line report the same symptoms. We start to strongly dislike the outside forms of socializing. It’s like attending an "AA" meeting in a bar with everyone holding a half sipped drink. We have become the net opponents’ worst nightmare. What first seemed like a luxury, crawling from bed to computer, not worrying about hair, and clothes and faces, has become avoidance, a lack of discipline. And once you start replacing real human contact with cyber-interaction, coming back out of the cave can be quite difficult. At times, I turn on the television and just leave it to chatter in the background, something that I’d never done previously. The voices of the programs soothe me, but then I’m jarred by the commercials. I find myself sucked in by soap operas, or compulsively needing to keep up with the possible angle of every story over and over and over, even when they are of no possible use to me. Work moves from foreground to background. Compared to the clear words of her boyfriend on screen, his accent becomes______.
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