2021年职称英语考试《理工类》考试共65题，分为单选题和多选题和判断题和计算题和简答题和不定项。小编为您整理阅读判断分析5道练习题，附答案解析，供您备考练习。

1、Radiocarbon DatingNowadays scientists can answer many questions about the past through a technique called radiocarbon (放射性碳), or carbon - 14 dating. One key to understanding how and why something happened is to discover when it happened.Radiocarbon dating was developed in the late 1940s by physicist Willard F. Libby at the University of Chicago. An atom of ordinary carbon, called carbon -12, has six protons (质子) and six neutrons (中子) in its nucleus (原子核). Carbon - 14, or C - 14, is a radioactive, unstable form of carbon that has two extra neutrons. It returns to a more stable form of carbon through a process called decay (衰减). This process involves the loss of the extra neutrons and energy from the nucleus.In Libby\'s radiocarbon dating technique, the weak radioactive emissions(放射)from this decay process are counted by instruments such as a radiation detector and counter. The decay rate is used to determine the proportion of C -14 atoms in the sample being dated.Carbon - 14 is produced in the Earth\'s atmosphere when nitrogen(氮) - 14, or N - 14, interacts with cosmic rays (宇宙射线). Scientists believe since the Earth was formed, the amount of nitrogen in the atmosphere has remained constant. Consequently, C -14 formation is thought to occur at a constant rate. Now the ratio of C -14 to other carbon atoms in the atmosphere is known. Most scientists agree that this ratio is useful for dating items back to at least 50,000 years.All life on Earth is made of organic molecules (分子) that contain carbon atoms coming from the atmosphere. So all living things have about the same ratio of C -14 atoms to other carbon atoms in their tissues (组织). Once an organism (有机体) dies it stops taking in carbon in any form, and the C -14 already present begins to decay. Over time the amount of C - 14 in the material decreases and the ratio of C - 14 to other carbon atoms goes down. In terms of radiocarbon dating, the fewer C -14 atoms in a sample, the older that sample is.An atom of ordinary carbon has. six protons and eight neutrons.【单选题】

A.Right

B.Wrong

C.Not mentioned

正确答案:B

答案解析:本题难度不大，答案依据比较明显，主要答案依据在文章第二段第二句：An atom of ordinary carbon，called carbon - 12，has six protons and six neutrons谈到普通碳原子有6个质子和6个中子，显然，题干和答案依据不符，答案是B。

2、Radiocarbon DatingNowadays scientists can answer many questions about the past through a technique called radiocarbon (放射性碳), or carbon - 14 dating. One key to understanding how and why something happened is to discover when it happened.Radiocarbon dating was developed in the late 1940s by physicist Willard F. Libby at the University of Chicago. An atom of ordinary carbon, called carbon -12, has six protons (质子) and six neutrons (中子) in its nucleus (原子核). Carbon - 14, or C - 14, is a radioactive, unstable form of carbon that has two extra neutrons. It returns to a more stable form of carbon through a process called decay (衰减). This process involves the loss of the extra neutrons and energy from the nucleus.In Libby\'s radiocarbon dating technique, the weak radioactive emissions(放射)from this decay process are counted by instruments such as a radiation detector and counter. The decay rate is used to determine the proportion of C -14 atoms in the sample being dated.Carbon - 14 is produced in the Earth\'s atmosphere when nitrogen(氮) - 14, or N - 14, interacts with cosmic rays (宇宙射线). Scientists believe since the Earth was formed, the amount of nitrogen in the atmosphere has remained constant. Consequently, C -14 formation is thought to occur at a constant rate. Now the ratio of C -14 to other carbon atoms in the atmosphere is known. Most scientists agree that this ratio is useful for dating items back to at least 50,000 years.All life on Earth is made of organic molecules (分子) that contain carbon atoms coming from the atmosphere. So all living things have about the same ratio of C -14 atoms to other carbon atoms in their tissues (组织). Once an organism (有机体) dies it stops taking in carbon in any form, and the C -14 already present begins to decay. Over time the amount of C - 14 in the material decreases and the ratio of C - 14 to other carbon atoms goes down. In terms of radiocarbon dating, the fewer C -14 atoms in a sample, the older that sample is.The radiocarbon dating technique is only about 40 years old.【单选题】

A.Right

B.Wrong

C.Not mentioned

正确答案:B

答案解析:本题有一定难度，需要认真寻找答案依据。主要答案依据在文章第二段第一句：Radiocarbon dating was developed in the late 1940s谈到放射性碳测定法源于20世纪40年代，显然，早就超过了40年历史，所以本题错误，答案是B。

3、Will We Take Vacation in Spaces?When Mike Kelly first set out to build his own private space-ferry service, he figured his bread-and-butter business would be lofting (发射) satellites into high-Earth orbit. Now he thinks he may have figured wrong. "People were always asking me when they could go," says Kelly, who runs Kelly Space & Technology out of San Bemardino, California. "I realized that real market is in space tourism."According to preliminary market surveys, there are 10,000 would-be-space-tourists willing to spend $1 million each to visit the final frontier. Space Adventure in Arlington, Virginia, has taken more than 130 deposits for a two-hour, $98, 000 space tour tentatively and somewhat dubiously (可疑地) set to actor by 2005. Gene Meyers of the space Island Group says: "Space is the next exotic(风光奇特的) vacation spot. "This may all sound great, but there are a few hurdles (困难). Putting a simple satellite into orbit with no oxygen, life support or return trip necessary already costs an astronomical (天文数字) $ 22,OOO/kg. And that doesn\'t include the oust of insuring rich and possibly litigious passenger. John Pike of the Federation of American Scientists acerbically (尖刻地) suggests that the entire group of entrepreneurs trying to corner (垄断) the space-tourism market have between them "just enough money to blow up one rocket."The U. S. space agency has plenty of money but zero interest in mailing space less expensive for the little guys. So the little guys are racing to do what the government has failed to do: design a reusable launch system that is inexpensive, safe and reliable. Kelly Space\'s prototype looks like a plane that has sprouted rocket engines. Rotary Rocket in Redwood City, California, has a booster with rotors to make a helicopter-style return to Earth; Kistler Aero-space in Kirkland, Washington, is piecing together its versions from old Soviet engines, shuttle-style thermal protection tiles and an elaborate parachute system. The first passenger countdowns are still years away, but bureaucrats at the Federal Aviation Administration in Washington are already informally discussing flight regulations. After all, you can\'t be too prepared, for a trip to that galaxy far, far away. For those who are intent on joining the 100-mile high club, Hilton and Budget are plotting to build space hotels. Before the Russian spaceship Mir came down, some people were talking about using it as a low-rent space hotel to reduce the cost. If a space hotel is finally built in space, and if you are thinking of staying in it, you may want to check the Michelin ratings before booking yourself a suite. We can infer from the context that the Michelin ratings can help people to find prices of hotels. 【单选题】

A.Right

B.Wrong

C.Notmentioned

正确答案:A

答案解析:依据是文章最后一句话：如果太空旅馆最终在太空建立，而你又正在考虑住在里边，在预定房间之前你或许想查看一下Michelin参数。

4、A Great Quake Coming?Everyone lives in San Francisco knows that earthquakes are common in the Bay Area and they can devastate. In 1906, for example, a major quake destroyed about 28000 buildings and killed hundreds, perhaps thousands of people. Residents now wonder when will the next "Big One" strike. It\'s bound to happen someday. At least seven active fault(断层) lines run through the San Francisco area. Faults are places where pieces of Earth\'s crust (地壳) slide past each other. When these pieces slip, the ground shakes.To prepare for that day, scientists are using new techniques to reanalyze the 1906 earthquake and predict how bad the damage might be when the next one happens.One new finding about the 1906 quake is that the San Andreas Fault split apart faster than scientists had assumed at the time. During small earthquakes, faults rupture(断裂) about 2.7 kilometers persecond. During bigger quakes, however, ruptures can happen faster than 3.5 kilometers persecond.At such high speeds, massive amounts of pressure build up, generating underground waves that can cause more damage than the quake itself. Lucky for San Francisco, these pressure pulses (脉冲) traveled away from the city during the 1906 event.Looking ahead, scientists are trying to predict when the next major quake will occur. Records show that earthquakes were common before 1906. Since then, the area has been relatively quiet. Patterns in the data, however, suggest that the probability of a major earthquake striking the Bay Area before 2032 is at least 62 percent.New buildings in San Francisco are quite safe in case of future quakes. Still, more than 84 percent of the city\'s buildings are old and weak. Analyses suggest that another massive earthquake would cause extensive damage.People who live there today tend to feel safe because San Francisco has remained pretty quiet for a while. According to the new research, however, it\'s not a matter that whether "the Big One" will hit here. It\'s just a matter of when.A major earthquake striking San Francisco someday is inevitable.【单选题】

A.Right

B.Wrong

C.Not mentioned

正确答案:A

答案解析:本题有一定难度，需要认真吃透句意，做好判断。答案依据在第五段。第五段最后一句：the probability of a major earthquake striking the Bay Area before 2032 is at least 62 percent.谈到在2032年前海湾地区发生大地震的可能性至少是62%，说明概率很高，所以本题正确，答案是A。

5、The Threat to KiribatiThe people of Kiribati are afraid that one day in the not-too-distant future, their country will disappear from the face of the earth-literally. Several times this year, the Pacific island nation has been flooded by a sudden high tide. These tides, which swept across the island and destroyed houses, came when there was neither wind nor rain. "This never happened before," say the older citizens of Kiribati.What is causing these mysterious high tides? The answer may well be global warming. When fuels like oil and coal are being burned, pollutants (污染物) are released. These pollutants trap heat in the earth\'s atmosphere. Warmer temperatures cause water to expand and also create more water by melting glaciers (冰川) and polar (极地的) ice caps.If the trend continues, scientists say, many countries will suffer, Bangladesh, for example, might lose one-fifth of its land. The coral (珊瑚) island nations of the Pacific, like Kiribati and the Marshall Islands, however, would face an even worse fate-they would be swallowed by the sea. The loss of these coral islands would be everyone\'s loss. Coral formations are home to more species than any other place on earth.The people of these nations feel frustrated. The sea, on which their economies have always been based, is suddenly threatening their existence. They don\'t have the money for expensive technological solutions like seawalls. And they have no control over the pollutants, which are being released mainly by activities in large industrialized countries. All they can do is to hope that industrialized countries will take steps to reduce pollution.High tides used to attack Kiribati when there was strong wind or heavy rain.【单选题】

A.Right

B.Wrong

C.Not mentioned

正确答案:A

答案解析:题干大意：当风强雨大的时候，高潮经常袭击基里巴斯。文章第一段最后两句提到：These tides，which swept across the island and destroyed houses, came when there was neither wind nor rain. "This never happened before," say the older citizens of Kiribati. 当无风无雨的时候这些高潮来横扫岛屿和破坏房屋，一位老人说：“这在以前从来都没有发生过”。意思就是说现在无风无雨也会出现高潮，而在过去只有大风大雨的时候才会出现高潮。故答案选A。