2021宁夏职称英语考试模拟卷.docx
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1、2021宁夏职称英语考试模拟卷本卷共分为1大题50小题,作答时间为180分钟,总分100分,60分及格。一、单项选择题(共50题,每题2分。每题的备选项中,只有一个最符合题意) 1.第二篇 Mind-reading MachineA team of researchers in California has developed a way to predict what kinds of objects people are looking at by scanning (扫描) whats happening in their brains.When you look at somethin
2、g, your eyes send a signal about that object to your brain. Different regions of the brain process the information your eyes send. Cells in your brain called neurons (神经元) are responsible for this processing.The fMRI (functional Magnetic Resonance Imaging) (功能性磁振造影) brain scans could generally match
3、 electrical activity in the brain to the basic shape of a picture that someone was looking at.Like cells anywhere else in your body, active neurons use oxygen. Blood brings oxygen to the neurons, and the more active a neuron is, the more oxygen it will consume. The more active a region of the brain,
4、 the more active its neurons, and in turn, the more blood will travel to that region. And by using fMRI, scientists can visualize (使显现) which parts of the brain receive more oxygen-rich blood - and therefore, which parts are working to process information.An fMRI machine is a device that scans the b
5、rain and measures changes in blood flow to the brain. The technology shows researchers how brain activity changes when a person thinks, looks at something, or carries out an activity like speaking or reading. By highlighting the areas of the brain at work when a person looks at different images, fMR
6、I may help scientists determine specific patterns of brain activity associated with different kinds of images.The California researchers tested brain activity by having two volunteers view hundreds of pictures of everyday objects, like people, animals, and fruits. The scientists used an fMRI machine
7、 to record the volunteers brain activity with each photograph they looked at. Different objects caused different regions of the volunteers brains to light up on the scan, indicating activity. The scientists used this information to build a model to predict how the brain might respond to any image th
8、e eyes see.In a second test, the scientists asked the volunteers to look at 120 new pictures. Like before, their brains were scanned every time they looked at a new image. This time, the scientists used their model to match the fMRI scans to the image. For example, if a scan in the second test showe
9、d the same pattern of brain activity that was strongly related to pictures of apples in the first test, their model would have predicted the volunteers were looking at apples.The expression highlighting the areas of the brain at work in paragraph 5 meansAgiving light to the parts of the brain that a
10、re processing information.Bmarking the parts of the brain that are processing information.Cputting the parts of the brain to work.Dpreventing the parts of the brain from working. 2.第一篇 WaterThe second most important constituent (构成成份) of the biosphere (生物圈) is liquid water. This can only exist in a
11、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 earths supply of water probably remains fairly constant in quantity. The total quantity of
12、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 Po
13、les and on mountains, and cannot be used by living systems until melted. Of the remaining fractional which is somewhat less than one per cent of the whole, there is 1020 times as much stored underground water as there is actually on the surface. There is also a tiny, but extremely important fraction
14、 of the water supply which is present as water vapor in the atmosphere.Water vapor 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 a
15、dded to it. From it the water comes out again as rain or snow, falling on either the sea or the 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
16、is restored by the runoff from the land in the form of rivers.The word fraction in the second paragraph meansAa very small amount.Ba large area.Can important system.Da major source of information 3. Radiocarbon DatingNowadays scientists can answer many questions about the past through a technique ca
17、lled radiocarbon (放射性碳), or carbon-14, dating. One key to understanding how and by something happened is to discover when it happened.Radiocarbon dating was developed in the late 1940s by physicist Willard F. Libby at he University of Chicago. An atom of ordinary carbon, called carbon-12, has six pr
18、otons(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 he extra neutrons and energy from the nucl
19、eus.In Libbys 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 Earths
20、atmosphere when nitrogen (氮)-14, or N-14,interacts with cosmic rays (宇宙射线). Scientists believe since the Earth was formed, the mount 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 toms in
21、 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 car
22、bon 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
23、-14 atoms in a sample, the older that sample is.The C-14 in an organism begins to decay when it diesARightBWrongCNot mentioned 4.Reduce PackagingPressure increased recently on British supermarkets and retailers to reduce packaging as part of an anti-waste campaign.(46) Britain generates 4.6 million
24、tons of household waste every year by packaging.Dozens of people have expressed anger at the excess of plastic wrapping.Campaigners have called on Britain to learn from other European countries.(47) When returned bottles are put in a vending machine (自动售货机), the deposit is refunded. Environmentalist
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