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1、2022年考博英语-沈阳药科大学考试内容及全真模拟冲刺卷（附带答案与详解）1. 单选题The number of people with Alzheimers disease in the United States is projected to more than double by 2050.问题1选项A.devisedB.thrustC.estimatedD.encountered【答案】C【解析】【选项释义】A. devised 设计 B. thrust 用力推C. estimated 估计 D. encountered 遇到【考查点】动词辨析【解题思路】原文指到2050年美国老年痴
2、呆症患者的数量将增加一倍以上，2050年是一个未来的年份，这个数据应该是预估的，C选项“估计”符合原文。原文be projected to“被预测”。【干扰项排除】A选项devised“设计”，美国的老年痴呆症患者的数量应该是自然发生的，不存在说被设计成多少；B选项thrust“用力推”，不符合原句逻辑；D选项encountered“遇到”，不符合原句逻辑。【句意】预计到2050年，美国老年痴呆症患者的数量将增加一倍以上。2. 单选题Space may seem remote, but its really not that far away. If you could drive your
3、car straight up, in just a few hours youd reach the altitude at which the space shuttle flies. The popular orbits for satellites begin twice as far upabout 400 miles above our heads. There telecommunications and weather satellites orbit at the same rate that Earth rotates, allowing them to hover abo
4、ve a single spot on the Equator.It was the explosions of derelict rockets that first drew NASAs attention to debris. In the 1970s Delta rockets left in orbit after delivering their payloads began blowing up. An investigation showed that the bulkheads separating the leftover fuels were probably crack
5、ing as a result of the rockets passing in and out of sunlight. NASA began recommending that leftover fuels be burned at the end of a flight, or that they be vented into space. Since then most public and private launchers have taken similar measuressuch steps are relatively inexpensive means of limit
6、ing debris. Still, every few months on average an old rocket or satellite explodes, flinging a cloud of debris into space.For many years NASA and the Department of Defense were skeptical about the dangers of space debris. The problem seemed abstract, residing more in computer models than in hard exp
7、erience. And it challenged the can-do mentality of space enthusiasts. Earths orbit seemed too large and empty to pollute. To its credit, NASA has long maintained a debris-research program, staffed by top-notch scientists who have persisted in pointing out the long-term hazards of space junk even whe
8、n the higher-ups at NASA havent wanted to hear about it. Then came the Challenger accident, in 1986. NASA officials realized that their emphasis on human space flight could backfire. If people died in space, public support for the shuttle program could unravel.Engineers took a new look at the shuttl
9、e and the International Space Station. Designed in the 1970s, when debris was not considered a factor, the shuttle was determined to be clearly vulnerable. After almost every mission widows on the shuttle are so badly pitted by microscopic debris that they need to be replaced. Soon NASA was flying t
10、he shuttle upside down and backward, so that its rockets, rather than the more sensitive crew compartments, would absorb the worst impacts. And engineers were adding shielding to the space stations most vulnerable areas.But adding shielding and repair kits wont solve the real problem. The real probl
11、em is that whenever something is put into an orbit, the risk of collision for all objects in that orbit goes up. Therefore, the only truly effective measure is a process known as deorbiting. The logic behind deorbiting has been inescapable since the beginning of the Space Age, yet it has just begun
12、to penetrate the consciousness of spacecraft designers and launchers. In 1995 NASA issued a guideline saying that satellites and the upper stages of rockets within 1,250 miles of Earth should remain in orbit for no longer than twenty-five years after the end of their functional lives. But the guidel
13、ine applies only to new spacecraft and can be waived if other considerations prevail. As a result NASA and the Defense Department also continue to leave the upper stages of some of their launch vehicles in orbit, partly because existing designs do not lend themselves to deorbiting.Furthermore, the c
14、haracter of the Space Age is changing. The private sector now puts more payloads into orbit than do NASA and the U.S. and Russian militaries combined. A score of communications companies in the U.S. and other countries have announced plans that will put hundreds of satellites into orbit over the nex
15、t decade. None of these companies is under any obligation to limit orbital debris. Companies that are launching large constellations of satellites are worried about collisions between the satellites, and they are well aware that a public-relations disaster would ensure if a piece of a shattered sate
16、llite smacked the station. As a result, some plan to deorbit satellites at the end of their useful lives. But other companies are leaving their satellites up or are counting on atmospheric drag to bring them down.Government regulations covering orbital debris are still rudimentary. For now, the federal agencies that have authority over commercial launches are waiting to see if the private sector can deal
