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職稱英語(yǔ)綜合類閱讀判斷模擬試題

　　以下是小編整理的職稱英語(yǔ)綜合類閱讀判斷模擬試題，希望對(duì)大家有所幫助

職稱英語(yǔ)綜合類閱讀判斷模擬試題

　　閱讀判斷

　　UFOS

　　Sixty years ago, a man named Kenneth Arnold saw something that we can still(51)today-something that changed popular culture for ever.

　　Flying his plane over mountains in the US state of Washington, he saw a line of strange objects, either crescent-shaped(月牙形的)or disc-like, flying 　　　　(52) the motion of a saucer(碟)skimming(飛速掠過(guò))on water.

　　The media soon picked up on the story - the Flying Saucers were here! Was the earth being(53)by creatures from another planet? Soon, So many sightings were made that the US military began to (54). 1t called these strange Objects UFOs - Unidentified Flying Objects, and that is how they are (55)today.

　　Military investigations found no evidence of visitors from outer space. But that did not stop the true(56). The military were (57)up, they said. Or maybe it was because the travelers from space were of such superior intelligence (58)they could hide from military analysts(分析家). 　People have always seen strange lights in the sky. In the past these were explained in (59)ways. In a world where religion was less influential and science fiction was popular, signs from God were replaced by visitors from other(60).

　　The date of the first UFO sightings was also significant. In l947, World War II had just ended and the(61)War was just beginning. Humanity seemed locked in endless conflicts. Like generations before them, people looked (62)the skies for help. But instead of seeking God, they looked for help from super-intelligent aliens(外星人)with (63)technology. Belief in UFOs became the first religion of science.

　　However, even people who believe in UFOs are not quite sure why they visit the earth. The universe is a big place and it is (64)to assume that there is life somewhere out there. It is possible that aliens have worked out how to travel through space. Yet some people report that they have been taken by aliens and have had experiments (65)on them. Why would anyone travel across half the universe to conduct medical experiments on people living in small towns in the United States?

　　51　A look B see C seek D feel

　　52　A below B before C with D under

　　53　A ruled B bombed C captured D visited

　　54　A investigate B attack C shoot D confront

　　55　A written B said C known D told

　　56　A believers B thinkers C followers D runners

　　57　A putting B covering C cheating D tricking

　　58　A which B what C this D that

　　59　A funny B crude C religious D foolish

　　60　A planets B continents C countries D regions

　　61　A cool B nuclear C Star D Cold

　　62　A above B to C at D up

　　63　A traditional B backward C classical D advanced

　　64　A unthinkable B Impossible C reasonable D unimaginable

　　65　A performed B studied C brought D taken

　　答案：51. B　　52. C　　53. D　　54. A　　55. C

　　56. A　　57. B　　58. D　　59. C　　60. A

　　61. D　　62. B　　63. D　　64. C　　65. A

　　New Understanding of Natural Silk’s Mysteries

　　Natural silk, as we all know, has a strength that man-made 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 (柔韌性) from an unusual arrangement of hydrogen bonds that are intrinsically 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 doesn't 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 (共價(jià)的) 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 (納米晶體) 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 that's 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 (納米碳管), 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.

　　16. MIT researchers carry out the study to illustrate an ancient Chinese proverb.