職稱英語理工類A級閱讀判斷真題

時間：2024-12-09 09:49:32 海潔職稱英語

職稱英語理工類A級閱讀判斷真題2套

　　無論是在學習還是在工作中，許多人都需要跟考試真題打交道，借助考試真題可以對一個人進行全方位的考核。什么類型的考試真題才能有效幫助到我們呢？以下是小編收集整理的職稱英語理工類A級閱讀判斷真題，僅供參考，希望能夠幫助到大家。

職稱英語理工類A級閱讀判斷真題2套

　　職稱英語理工類A級閱讀判斷真題 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.

　　探索蠶絲的奧秘，制造更加結實而輕盈的材料

　　克雷·迪洛著

　　我們都知道，蠶絲具有的韌性是人造織物長期奮力追求的目標。在一項研究中(該項研究成果聽起來更像一則古代中國諺語，而不是材料科學的突破)，麻省理工學院的研究人員發現，蠶絲的力量源于其脆弱，或者，更具體地說，是它的多方面的脆弱。蠶絲的異常耐久性和延展性來自一種特別的氫鍵結構，這些氫鍵本質上非常脆弱，但它們共同創造了一種強壯而富有彈性的結構。

　　大多數材料(特別是那些要求硬度很高的材料)的韌性來自脆性。因此，和蜘蛛制造的蛛絲類似的蠶絲，因其重量輕，延展性強和韌性高，長期以來引起了生物學家和工程師的興趣(同樣重量，蠶絲比鋼要壯，也不那么脆)。但表面上，蠶絲看起來卻不那么強壯;從分子結構上看，它們是由氫鍵組成的，氫鍵比其他分子中發現的共價鍵要脆弱得多。

　　為了更好地了解蠶絲如何以如此脆弱的化學鍵產生這么強壯的力，麻省理工學院的研究小組創造了一套計算機模型，這種模型能夠讓他們在原子層次上觀察蠶絲的活動方式。他們發現，微小蠶絲納米晶體的結構使氫鍵能夠齊心協力地合作，相互增援，對抗外力，同時，當外力減弱時也隨之慢慢減弱，這樣就不至于在蠶絲的整體結構上出現突然的斷裂。

　　這樣，天然絲能夠既伸縮和彎曲，又能夠保持極高的韌力。對于蜘蛛和蜜蜂之類的昆蟲來說這也沒什么，但對于蠶絲幾何形狀的.這種了解，可能幫助人們制造出比我們面前能夠制造的材料更結實而又更柔軟的新材料。最好和最結實的材料通常是很昂貴而又難以制造的(需要高溫處理，或者高能耗處理)。

　　通過研究蠶絲作為一個例子，研究人員有可能設計出制造材料的一種新方法，即用廉價材料和弱鍵，制造不那么堅硬而又柔軟，但比目前所用的任何材料都結實的材料。如果你認為不研究碳納米管的理論，就能從這一則材料學信息中獲取制造方法，那請三思。麻省理工學院研究小組已經在實驗室利用比蠶絲還結實的材料(比如碳納米管)研究合成類似蠶絲一樣的結構。超級蠶絲即將出現。

　　職稱英語理工類A級閱讀判斷真題 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