2024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。小编每天为您准备了5道每日一练题目（附答案解析），一步一步陪你备考，每一次练习的成功，都会淋漓尽致的反映在分数上。一起加油前行。

1、Seeing Red Means Danger AheadThe colｏｒred often means danger ａｎｄ　by paying attention, accidents can be prevented. In the future, the colｏｒred also may help prevent danger at construction sites. Thanks to new work by engineers, bridge supports ｏｒother kinds of materials, could one day contain a colｏｒ- changing material. It will turn red before a structure collapses ｏｒfalls apart.The secret behind the colｏｒ- changing material is a particular type of molecule (分子). A molecule is aｇｒｏｕｐof atoms (原子) held together by chemical bonds. Molecules come _____ all shapes ａｎｄ　sizes ａｎｄ　make up everything you can see, touch ｏｒfeel. How a molecule behaves depends on what kinds of atoms it contains ａｎｄ　how they\'re held together.When a polymer (聚合物) containing a colｏｒ- changing molecule called a mechanophore (机械响应性聚合物) is about to break, it produces a color. When a polymer with mechanophore molecules becomes "injured" ｏｒweak, one of the mechanophore bonds breaks ａｎｄ　the material turns red. "It\'s a really simple detection method," says Nancy Sottos, one of the scientists who worked on the project. Sottos ａｎｄ　her team tested the colｏｒ- changing polymers in their lab. The test results proved encouraging.There is a way to get rid of the red colｏｒlight. When a bright light is shone on the mechanophore, the broken bond is fixed ａｎｄ　the red colｏｒdisappears. Thus "self - healing" may be a problem fｏｒengineers. They need to use the colｏｒ- changer in big construction projects that will be outside, under sunlight. ａｎｄ　sunlight will make the mechanophore\'s warning system useless.Sottos ａｎｄ　her fellow scientists still have a lot of work to do before the colｏｒ- changing molecules can be used outside the lab.【单选题】

A.for

B.in

C.from

D.at

正确答案:B

答案解析:本题有一定难度，干扰项有一定的干扰性，本题考查固定搭配come in，指“以……方式出来”，答案是B。

2、Seeing Red Means Danger AheadThe colｏｒred often means danger ａｎｄ　by paying attention, accidents can be prevented. In the future, the colｏｒred also may help prevent danger at construction sites. Thanks to new work by engineers, bridge supports ｏｒother kinds of materials, could one day contain a colｏｒ- changing material. It will turn red before a structure collapses ｏｒfalls apart.The secret behind the colｏｒ- changing material is a particular type of molecule (分子). A molecule is aｇｒｏｕｐof atoms (原子) held together by chemical bonds. Molecules come in all shapes ａｎｄ　sizes ａｎｄ　make up everything you can see, touch ｏｒfeel. How a molecule behaves depends on what kinds of atoms it contains ａｎｄ　how they\'re held together.When a polymer (聚合物) containing a colｏｒ- changing molecule called a mechanophore (机械响应性聚合物) is about to break, it produces a color. When a polymer with mechanophore molecules becomes "injured" ｏｒweak, one of the mechanophore bonds _____ ａｎｄ　the material turns red. "It\'s a really simple detection method," says Nancy Sottos, one of the scientists who worked on the project. Sottos ａｎｄ　her team tested the colｏｒ- changing polymers in their lab. The test results proved encouraging.There is a way to get rid of the red colｏｒlight. When a bright light is shone on the mechanophore, the broken bond is fixed ａｎｄ　the red colｏｒdisappears. Thus "self - healing" may be a problem fｏｒengineers. They need to use the colｏｒ- changer in big construction projects that will be outside, under sunlight. ａｎｄ　sunlight will make the mechanophore\'s warning system useless.Sottos ａｎｄ　her fellow scientists still have a lot of work to do before the colｏｒ- changing molecules can be used outside the lab.【单选题】

A.closes

B.breaks

C.increases

D.burns

正确答案:B

答案解析:本题有一定难度，关键在理解好文章上下文意义，文章此处要表达的是“断开”的意思，答案是B。

3、Radiocarbon DatingNowadays scientists can answer many questions about the past through a technique called radiocarbon (放射性碳), ｏｒcarbon - 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, ｏｒC - 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 detectｏｒａｎｄ　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, ｏｒN - 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 fｏｒdating 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.Radiocarbon is reliable in dating an object back to at least 50,000 years.【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，答案依据比较明显，主要答案依据在文章第四段最后一句：Most scientists agree that this ratio is useful fｏｒdating items back to at least 50,000 years谈到科学家相信，这样的比率对于测定5万多年前的物体有用，题干是其近义解释，所以正确，答案是A。

4、WaterThe second most important constituent (构成成份) of the biosphere (生物圈) is liquid water. This can only exist in a very narrow range of temperatures, since water freezes at 0℃ ａｎｄ　boils at 100℃. Life as we know it would only be possible on the surface of a planet which had temperatures somewhere within this narrow range.The earth\'s supply of water probably remains fairly constant in quantity. The total quantity of water is not known very accurately, but it is about enough to cover the surface of the globe to a depth of about two ａｎｄ　three - quarter kilometers. Most of it is in the form of the salt water of the oceans about 97 percent. The rest is fresh, but three -quarters of this is in the form of ice at the Poles ａｎｄ　on mountains, ａｎｄ　cannot be used by living systems until melted. Of the remaining fraction, which is somewhat less than one percent of the whole, there is 10 -20 times as much stored underground water as there is actually on the surface. There is also a tiny, but extremely important fraction of the water supply which is present as water vapour in the atmosphere.Water vapour in the atmosphere is the channel through which the whole water circulation (循环) of the biosphere has to pass. Water evaporated (蒸发) from the surface of the oceans, from lakes ａｎｄ　rivers ａｎｄ　from moist (潮湿的) earth is added to it. From it the water comes out again as rain ｏｒsnow, falling on either the sea ｏｒthe land. There is, as might be expected, a more intensive evaporation per unit area over the sea ａｎｄ　oceans than over the land, but there is more rainfall over the lａｎｄ　than over the oceans ａｎｄ　the balance is restored by the runoff from the lａｎｄ　in the form of rivers.The word "fraction" in the second paragraph means ______.【单选题】

A.a very small amount

B.a large area

C.an important system

D.a majｏｒsource of information

正确答案:A

答案解析:本题难度不大，文章第二段第四句谈到剩余部分大约小于1%，可以判断fraction意思是指“很少一部分”，此外也可迅速查词典，确定答案，答案是A。

5、One Good Reason to Let Smallpox LiveIt\'s now a fair bet that we will never see the total extinction (灭绝) of the smallpox (天花) virus. When smallpox was completely got rid of in the world, scientists wanted to destroy the killer virus in the last two labs, one in the US ａｎｄ　one in Russia. They asked: If smallpox has truly gone from the planet, what point was there in keeping these reserves?In reality, of course, it was naive to imagine that everyone would let go of such a powerful potential weapon. Undoubtedly several nations still have a few vials (小药瓶). ａｎｄ　the last "official" stocks of live Virus bred mistrust of the US ａｎｄ　Russia, _____ no obvious gain.Now American researchers have found an animal model of the human disease, opening the way fｏｒtests on new treatments ａｎｄ　vaccines(疫苗). So once again there\'s a good reason to the virus, just in keep the disease puts in a reappearance.How do we case with the mistrust of the US ａｎｄ　Russia? deal. Keep the virus Simple international support in a well - guarded UN laboratory that\'s open to all countries. The US will object, of course, just as it with a multilateral (多边的) approach to just about everything. But it doesn\'t mean the idea is rejects. If the virus is useful, then let\'s wrong it the servant of all humanity make not just a part of it.【单选题】

A.in

B.for

C.at

D.of

正确答案:B

答案解析:本题有一定难度，考查for的用法，for除了做介词外，还可做连词，表示“因为”，文章此处是说“……因为没有获得明显的收获”，答案是B。