2020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.The half - life of C - 14 is about 25 ,000 years.【单选题】

A.Right

B.Wrong

C.Not mentioned

正确答案:C

答案解析:本题有较大难度，答案依据不明显，需要通读全文作出判断。通读全文后可以发现文章并未提及碳的半衰期是25，000年，所以本题是未提及的，答案是C。

2、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.The highest speed of fault ruptures in the 1906 quake was more than 3,5 kilometers per second.【单选题】

A.Right

B.Wrong

C.Not mentioned

正确答案:A

答案解析:本题难度不大，找到答案依据不难。答案依据在第三段。第三段最后一句：During bigger quakes, however, ruptures can happen at rates faster than 3.5 kilometers per second.谈到在更大的地震中，断裂速度可以高于3.5千米每秒。所以本题正确，答案是A。

3、Inventor of LEDWhen 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 lOth 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. " Holonyrak said. Holonyak, 75, was a student of john Bardeen, an inventor of the transistor, in the early 1950s. After graduate school, Holonyak worked at Ben 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 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. The Lemelson-MIT Prize has a history of over 100 years.【单选题】

A.Right

B.Wrong

C.Not mentioned

正确答案:B

答案解析:根据主题句内容判断Lemelson-MIT奖成立的时间是1994年，因此问题句中说的“Lemelson-MIT奖有100多年的历史”与原文内容矛盾。

4、The SmogFor over a month, Indonesia was in crisis. Forest fires raged out of control as the country suffered its worst drought for 50 years. Smoke from the fires mixed with sunlight and hot dry air to form a cloud of smog. This pollution quickly spread and within days it was hanging over neighboring countries including Malaysia, Singapore and Thailand. When the smoke combined with pollution from factories and cars, it soon became poisonous. Dangerous amounts of CO became trapped under the smog and pollution levels rose. People wheezed (喘息) and coughed as they left the house and their eyes watered immediately. The smog made it impossible to see across streets and whole cities disappeared as grey soot(烟灰) covered everything. In some areas, water was hosed (用胶管浇) from high-rise city buildings to try and break up the smog. Finally, heavy rains, which came in November. Put out the fires and clear the air. But the environmental costs and health problems will remain. Many people from South-Eastern Asian cities already suffer from breathing huge amounts of car exhaust fumes and factory pollution Breathing problems could well increase and many non-sufferers may have difficulties for the first time. Wildlife has suffered too. In lowland forests, elephants, deer, and tigers have been driven out of their homes by smog. But smog is not just an Asian problem. In fact. was world was first used in London in 1905 to describe the mixture of smoke and thick fog. Fog often hung over the capital. Sometimes the smog was so thick and poisonous that people were killed by breathing problems or in accidents. About 4, 000 Londoners died within five days as a result of thick smog in 1952. The forest animals haven\'t been affected by the smog. 【单选题】

A.Right

B.Wrong

C.Not mentioned

正确答案:B

答案解析:题句的意思是“森林里的动物未曾受到烟雾的影响”。文中第4段最后一句提到一些动物由于烟雾逃出了森林。题句意思与原文有出入，故选B。

5、Black HolesMost scientists agree that black holes exist but are nearly impossible to locate. A black hole in the universe is not a solid object, like a planet, but it is shaped like a sphere (球体). Astronomers (天文学家) think that at the center of a black hole there is a single point in space with infinite (无限的) density (稠密).This single point is called a singularity (奇点). If the singularity theory is correct, it means that when a massive star collapses, all the material in it disappears into the singularity. The center of a black hole would not really be a hole at all, but an infinitely dense point. Anything that crosses the black hole is pulled in by its great gravity.Although black holes do exist, they are difficult to observe. These are the reasons,?No light or anything else comes out of black holes. As a result, they are invisible to a telescope.?In astronomical terms, black holes are truly. For example, a black hole formed by the collapse of a giant star would have an event horizon (视界) only 18 miles across.?The nearest black holes would be dozens of light years away from Earth. One light year is about 6 trillion (万亿) miles. Even the most powerful telescopes could not pick out an object so small at such a great distance.In 1994 the Hubble Space Telescope provided evidence that black holes exist. There are still answers to be found, however, so black holes remain one of the mysteries of the universe. (2007年)The attraction of two large stars leads to gravity.【单选题】

A.Right

B.Wrong

C.Not mentioned

正确答案:C

答案解析:题干大意：两个巨大行星的引力导致重力。用数字two和中心词gravity（吸引力）回到原文定位，文章并没有相关信息。故答案选C。