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2022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、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.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。
2、The great change of the city astonished all the visitors.【单选题】
A.surprised
B.scared
C.excited
D.moved
正确答案:A
答案解析:这座城市发生的大变化使所有的参观者惊讶。本题难度不大,干扰项干扰不强。astonished和surprised都可指“吃惊的”,B项指“使惊吓”,最佳答案是A。
3、Weaving with LightIn the Sierra Madre mountain range of west central Mexico, the native Huichol people live much the way their ancestors did-without electricity. That\'s because it\'s too expensive to string power lines to the remote mountain areas where they live. To help support themselves, the Huichol create beautiful artwork. They sell their art in cities hundreds of miles away from their villages. and without electricity, at home oron the road, they can only work during daylight hours. When it gets dark, they must stop whatever they\'re doing.Now, a team of scientists, designers and architects is using new technologies to provide the Huichol with light after the sun sets. The scientists technique involves weaving tiny electronic crystals into fabrics that can be made into clothes, bags, orother items.By collecting the sun\'s energy during the day, these lightweight fabrics provide bright white light at night. Their inventors have named the fabrics "Portable Lights," Portable Lights have the potential to transform the lives of people without electricity around the world, says project leader Sheila Kennedy."Our invention," Kennedy says, "came from seeing how we could transform technology we saw every day in the United States and move it into new markets forpeople who didn\'t have a lot of money."At the core of Portable Light technology are devices called high - brightness light - emitting diodes, orHB LEDs. These tiny lights appear in digital clocks, televisions and streetlights.LEDs are completely different from the light bulbs. Most of those glass bulbs belong to a type called incandescent lights. Inside, electricity heats a metal coil to about 2,200 degrees Celsius. At that temperature, bulbs give off light we can see.Ninety percent of energy produced by incandescent lights, however, is heat and invisible. With all that wasted energy, bulbs burn out quickly. They are also easily broken.LEDs, on the other hand, are like tiny pieces of rock made up of molecules that are arranged in a crystal structure. When an electric current passes through an LED, the crystal structure produces light. Unlike incandescent bulbs, they can produce light of various colors. Within an LED, the type of molecules and their particular arrangement determines what coloris produced.The central part of the Portable Lights technology is ______.【单选题】
A.glass bulbs
B.digital clocks
C.incandescent lights
D.HB LEDs
正确答案:D
答案解析:本题有一定难度,关键在吃透句意,答案依据比较明显,带着题干信息词回文章定位,答案依据主要在文章第五段第一句:At the core of Portable Light technology are devices called high - brightness light - emitting diodes orHB LEDs。其中core和题干里的central part是同义词,回来看选项,D项和原文句意相符,答案是D。
4、Jack packed up all the things he had accumulated over the last ten years.【单选题】
A.future
B.far
C.past
D.near
正确答案:C
答案解析:杰克把过去10年里攒的所有东西都收拾好打行李了。本题难度不大,干扰项干扰不强,是送分题。last和past都指“过去的”是同义词,最佳答案是C。
5、The Book of LifeSo far, scientists have named about 1.6 million living species, and that\'s a just a fraction of that probably exists on Earth. With so many plants, animals and other creatures coveting the planet, it can be tough to figure out what type of spider is moving up your leg orwhat kind of bird is flying by.A soon - to - be - started Web site might help. An international team of researchers has announced the creation of Web - based Encyclopedia of life( EOL). The project aims to catalog every species on Earth in a single, easy - to - use reference guide.To get the encyclopedia started, the creators will use information from scientific databases that already exist. and eventually, in special sections of the site, nonscientist with specialized knowledge will get to join in. Bird - watchers, forexample, will be able to input which bird they\'ve seen and where. The technology forthis kind of tool has only become available.As the EOL develops, you might find it useful forschool projects. The site will feature special pages forkids who are studying ecosystems (生态系统) in their neighborhoods. To make sure the encyclopedia is accurate, scientists will review much of the information added to it. People who visit the site will be able to choose to leave out pages that haven\'t been reviewed.Another convenient feature of the EOL is that you\'ll be able to pick the level of detail you want to see to match your interest, age and knowledge. If you wanted to learn about bears fora science class report, forexample, you could use the "novice" setting to get basic information about the animals. On the "expert" setting, on the other hand, you could get much more detailed information about the history, literature and exploration of bears.It now takes years forscientist to collect all the data they need to describe and analyze species. The creatorof the Encyclopedia of Life hope that their new tool will speed up that process."Spider" and "bird" mentioned in Paragraph 1 are examples to illustrate ______.【单选题】
A.there are numerous living species on Earth
B.animals are people\'s friends
C.it is easy to see spiders and birds
D.here are many types of spiders and birds
正确答案:A
答案解析:本题有一定难度,带着题干信息词回文章定位,答案依据主要在文章第一段:So far, scientists have named about l.6 million living species, ...it can be tough to figure out what type of spider is moving up your leg orwhat kind of bird is flying by.谈到了地球物种数量巨大,回来看选项,A项和原文句意相近,是答案。
为什么商务英语考试中有的考生不允许入场?:为什么商务英语考试中有的考生不允许入场?考点将拒绝考生入场,并不予改期考试或退还考费:1. 抵达考点与网上报名所选考点不一致;2. 未携带准考证或规定的有效身份证件;3. 所携身份证件的有效性未通过核验;4. 身份证件类型和号码与所持准考证显示信息不符;5. 身份证件相片与本人明显不符;6. 未按准考证规定时间到达考场;7. 不服从监考人员的管理,扰乱考场秩序。
需要具备怎样的基础才能备考商务英语BEC中级?:商务英语中级需要有大学英语四级到六级的水平。
学习商务英语BEC初级需要具备怎样的基础?:学习商务英语BEC初级需要具备怎样的基础?根据BEC考试大纲的要求,学习BEC初级需要有公共英语四级的水平。
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