首页
外语
计算机
考研
公务员
职业资格
财经
工程
司法
医学
专升本
自考
实用职业技能
登录
外语
The Stone age, the Iron age. Entire epochs have been named for materials. So what to name the decades ahead? The choice will be
The Stone age, the Iron age. Entire epochs have been named for materials. So what to name the decades ahead? The choice will be
admin
2009-06-24
78
问题
The Stone age, the Iron age. Entire epochs have been named for materials. So what to name the decades ahead? The choice will be tough. Welcome to the age of superstuff. Material science—once the least sexy technology—is bursting with new, practical discoveries led by superconducting ceramics that may revolutionize electronics. But superconductors are just part of the picture: from houses and cars to cook pots and artificial teeth, the world will sometime be made of different staff. Exotic plastics, glass and ceramics will shape the future just as surely as have genetic engineering and computer science.
The key to the new materials is researchers’ increasing ability to manipulate substances at the molecular level. Ceramics, for instance, have long been limited by their brittleness. But by minimizing the microscopic imperfections that cause it, scientists are making far stronger ceramics that still retain such qualities as hardness and beat resistance. Ford Motor Co. now uses ceramic tools to cut steel. A firm called Kyocera has created a line of ceramic scissors and knives that stay sharp for years and never rust or corrode.
A similar transformation has overtaken plastics. High-strength polymers now form bridges, ice-skating rinks and helicopter rotors. And one new plastic that generates electricity when vibrated or pushed is used in electric guitars, touch sensors for robot hands and karate jackets that automatically record each punch and chop. Even plastic litter, which once threatened to permanently blot the landscape, has proved amenable to molecular tinkering. Several manufacturers now make biodegradable forms; some plastic six-pack rings for example, gradually decompose when exposed to sunlight. Researchers are developing ways to make plastics as recyclable as metal or glass. What’s more, composites—plastic reinforced with fibres of graphite or other compounds—made the round-the-world flight of the voyager possible and have even been proved in combat: a helmet saved all infantryman’s life by deflecting two bullets in the Grenada invasion.
Some advanced materials are old standard with a new twist. The newest fiberoptic cables that carry telephone calls crass-country are made of glass so transparent that a piece of 100 miles thick is clearer than a standard window pane.
But new materials have no impact until they are made into products. And that transition could prove difficult, for switching requires lengthy research and investment. It can be said a timer handle on how to move to commercialization will determine the success or failure of a country in the coming future.
选项
A、Two.
B、Three.
C、Four.
D、Five.
答案
B
解析
转载请注明原文地址:https://www.kaotiyun.com/show/1BHd777K
本试题收录于:
公共英语五级笔试题库公共英语(PETS)分类
0
公共英语五级笔试
公共英语(PETS)
相关试题推荐
A.OtherthreatstotheBeringseaB.Pollack—themostimportantkindofishC.TheproblemsmanycountiesfaceD.HowtoprotectBe
OceanEcosystemEndangered1.SpanningtheoceanicdividebetweentheU.S.andRussia,itisoneoftherichestandmostcomm
Wederiveknowledgemainlyfrombooks.
Duringhislifetimehewasabletoaccumulatequiteafortune.
TheauthormentionsthetornadoinEdmonton,Canada,inordertogiveanexampleofadamagingstorm.Meteorologistsshouldsta
Accordingtothepassage,duringtheCarnivalpeopleinRiodidallofthefollowingEXCEPTAccordingtothepassage,BobNadka
Accordingtothepassage,duringtheCarnivalpeopleinRiodidallofthefollowingEXCEPTHowlongdoesthecarnivallast?
TheAmericanFamilyIntheAmericanfamilythehusbandandwifeusuallyshareimportantdecisionmaking.Whenthechildrenare(5
EleanorRoosevelt’sdedicationtohumanitariancauseswonheraffectionandhonorathomeandabroad.
Ifwecanovercomeourpresentdifficulties,theneverythingshouldbeallright.
随机试题
下列哪一选项描述的是竞争关系?
此项决议已经大会讨论、通过,请各单位_______执行。[遵照并服从]
某企业拟投资兴建一生产项目。预计该生产项目的计算期(生命周期)为12年,其中建设期为2年,生产期为10年。项目投资的现金流量部分数据见表1.1。项目的折现率按照银行长期贷款年利率6.72%计算(按季计息)。短期贷款利率为5%。问题:根据计算结果,评
按照现代质量管理理念,建设工程项目功能性质量必须以()为焦点。
某城市目前共有销售员5000人,他们的市场工资率是8元/小时。如果该城市的销售员的供给是单位弹性的,要使销售员的供给人数增加到75500人,则市场工资率至少应当提高到()元/小时。
心理测验按测验的内容可分为两大类,一类是能力测验,一类是()。
下列选项中属于《学记》中的教育主张的是()。
具有高科技含量、高文化附加值的各类创新型产业所形成的经济形态可以被称为“()”。
受遗赠人应当在知道受遗赠后()内,作出接受或者放弃受遗赠的表示。
稳定的社会就是和谐社会。
最新回复
(
0
)