职称英语理工类A级阅读判断真题

时间：2024-12-09 09:49:32 海洁职称英语我要投稿

职称英语理工类A级阅读判断真题2套

　　无论是在学习还是在工作中，许多人都需要跟考试真题打交道，借助考试真题可以对一个人进行全方位的考核。什么类型的考试真题才能有效帮助到我们呢？以下是小编收集整理的职称英语理工类A级阅读判断真题，仅供参考，希望能够帮助到大家。

职称英语理工类A级阅读判断真题2套

　　职称英语理工类A级阅读判断真题 1

　　New Understanding of Natural Silks Mysteries Could Lead to Stronger, Lighter Materials

　　By Clay Dillow

　　Natural silk, as we all know, has a strength that manmade materials have long struggled to match. In a discovery that sounds more like an ancient Chinese proverb than a materials science breakthrough, MIT researchers have discovered that silk gets its strength from its weakness. Or, more specifically, its many weaknesses. Silk gets its extraordinary durability and ductility from an unusual arrangement of hydrogen bonds that are inherently very weak but that work together to create a strong, flexible structure.

　　Most materials -- especially the ones we engineer for strength -- get their toughness from brittleness. As such, natural silks like those produced by spiders have long fascinated both biologists and engineers because of their light weight, ductility and high strength (pound for pound, silk is stronger than steel and far less brittle). But on its face, it doesnt seem that silks should be as strong as they are; molecularly, they are held together by hydrogen bonds, which are far weaker than the covalent bonds found in other molecules.

　　To get a better understanding of how silk manages to produce such strength through such weak bonds, the MIT team created a set of computer models that allowed them to observe the way silk behaves at the atomic level. They found that the arrangement of the tiny silk nanocrystals is such that the hydrogen bonds are able to work cooperatively, reinforcing one another against external forces and failing slowly when they do fail, so as not so allow a sudden fracture to spread across a silk structure.

　　The result is natural silks that can stretch and bend while retaining a high degree of strength. But while thats all well and good for spiders, bees and the like, this understanding of silk geometry could lead to new materials that are stronger and more ductile than those we can currently manufacture. Our best and strongest materials are generally expensive and difficult to produce (requiring high temperature treatments or energy-intensive processes).

　　By looking to silk as a model, researchers could potentially devise new manufacturing methods that rely on inexpensive materials and weak bonds to create less rigid, more forgiving materials that are nonetheless stronger than anything currently on offer. And if you thought you were going to get out of this materials science story without hearing about carbon nanotubes, think again. The MIT team is already in the lab looking into ways of synthesizing silk-like structures out of materials that are stronger than natural silk -- like carbon nanotubes. Super-silks are on the horizon.

　　探索蚕丝的奥秘，制造更加结实而轻盈的材料

　　克雷·迪洛著

　　我们都知道，蚕丝具有的韧性是人造织物长期奋力追求的目标。在一项研究中(该项研究成果听起来更像一则古代中国谚语，而不是材料科学的突破)，麻省理工学院的研究人员发现，蚕丝的力量源于其脆弱，或者，更具体地说，是它的多方面的脆弱。蚕丝的异常耐久性和延展性来自一种特别的氢键结构，这些氢键本质上非常脆弱，但它们共同创造了一种强壮而富有弹性的结构。

　　大多数材料(特别是那些要求硬度很高的材料)的韧性来自脆性。因此，和蜘蛛制造的蛛丝类似的蚕丝，因其重量轻，延展性强和韧性高，长期以来引起了生物学家和工程师的兴趣(同样重量，蚕丝比钢要壮，也不那么脆)。但表面上，蚕丝看起来却不那么强壮;从分子结构上看，它们是由氢键组成的，氢键比其他分子中发现的共价键要脆弱得多。

　　为了更好地了解蚕丝如何以如此脆弱的化学键产生这么强壮的力，麻省理工学院的研究小组创造了一套计算机模型，这种模型能够让他们在原子层次上观察蚕丝的活动方式。他们发现，微小蚕丝纳米晶体的结构使氢键能够齐心协力地合作，相互增援，对抗外力，同时，当外力减弱时也随之慢慢减弱，这样就不至于在蚕丝的整体结构上出现突然的断裂。

　　这样，天然丝能够既伸缩和弯曲，又能够保持极高的韧力。对于蜘蛛和蜜蜂之类的昆虫来说这也没什么，但对于蚕丝几何形状的.这种了解，可能帮助人们制造出比我们面前能够制造的材料更结实而又更柔软的新材料。最好和最结实的材料通常是很昂贵而又难以制造的(需要高温处理，或者高能耗处理)。

　　通过研究蚕丝作为一个例子，研究人员有可能设计出制造材料的一种新方法，即用廉价材料和弱键，制造不那么坚硬而又柔软，但比目前所用的任何材料都结实的材料。如果你认为不研究碳纳米管的理论，就能从这一则材料学信息中获取制造方法，那请三思。麻省理工学院研究小组已经在实验室利用比蚕丝还结实的材料(比如碳纳米管)研究合成类似蚕丝一样的结构。超级蚕丝即将出现。

　　职称英语理工类A级阅读判断真题 2

　　Bees and Colour

　　On our table in the garden we put a blue card, and all around this blue card we put a number of different grey cards. These trey cards are of all possible shades of grey and include white and black. On each card a watch-glass is placed. The watch-glass on the blue card has some syrup in it; all the others are empty. After a short time bees find the syrup, and they come for it again and again. Then, after some hours, we take away the watch-glass of syrup which was on the blue card and put an empty one in its place.

　　Now what do the bees do? They still go straight to the blue card, although there is no syrup there. They do not go to any of the grey cards, in spite of the fact that one of the grey cards is of exactly the same brightness as the blue card. Thus the bees do not mistake any shade of grey for blue. In this way we have proved that they do really see blue as a colour.

　　We can find out in just the same way what other colours bees can see. It turns out that bees can see various colours, but these insects differ from us as regards their colour-sense in two very interesting ways. Suppose we train bees to come to a red card, and, having done so, we put the red card on the table in the garden among the set of different grey cards. This time we find that the bees mistake red for dark grey or black. They cannot distinguish between them. This means that red is not a colour at all for bees; for them it is just dark grey or black.

　　That is one strange fact; here is another. A rainbow is red on one edge, violet on the other. Outside the violet of the rainbow there is another colour which we cannot see at all. This colour beyond the violet, invisible to us, is called the ultra-violet. Although it is invisible, we know that the ultra-violet is there because it affects a photographic plate. Now, although we are unable to see ultra-violet light, bees can do so; for them ultra-violet is a colour. Thus bees see a colour w

　　ahich we cannot even imagine. This has been found out by training bees to come for syrup to various parts of a spectrum, or artificial rainbow, thrown by a prism on a table in a dark room. In such an experiment the insects can be taught to fly to the ultra-violet, which for us is just darkness.

　　1. The experiment with bees described in the first and second paragraphs tell us that bees regard blue as a colour.

　　A. True

　　B. False

　　C. Not mentioned

　　2. The third paragraph tells us that bees also regard red as a colour.

　　A. True

　　B. False

　　C. Not mentioned

　　3. The experiment described in the second paragraph aimed to find out that bees are not able to see grey as a colour.

　　A. True

　　B. False

　　C. Not mentioned