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 Development of Rubber Here is the story of rubber. From the earliest time it was common knowledge (51) the Peruvians tha
The Development of Rubber Here is the story of rubber. From the earliest time it was common knowledge (51) the Peruvians tha
admin
2012-09-10
55
问题
The Development of Rubber
Here is the story of rubber. From the earliest time it was common knowledge (51) the Peruvians that when a cut was made in the outside skin of a rubber tree, a white liquid (52) milk came out, and that (53) this a sticky (粘的) mass of rubber might be made. This rubber is soft when warm, so that it is possible to give it any (54) . The Peruvians made the (55) that it was very good for keeping out the wet. Then in the early 1800’s, the Americans made use of it for the first time. First they made overshoes to (56) their feet dry. Then came a certain Mr. Mackintosh, who made coats of cloth covered with natural rubber. From that day to this we have been coating cloth with rubber as Mr. Mackintosh (57) , and our raincoats are still named after him.
But these first rubber overshoes and raincoats were all soft and sticky in summer, and (58) and inelastic (无弹性的) in the winter when it was col D. But the rubber we have today is soft and elastic (有弹性的), (59) very strong m even in the warmest summer and the coldest winter. This was made (60) by a man called Goodyear. After many (61) , he found that nitric acid (硝酸) made the rubber much better, but it is not hard and strong enough. Then a strange thing took(62) . A friend of his, Nicholas Hayward, had the idea in his sleep that rubber might be made hard and strong if mixed with sulfur (硫磺) and put in the sun. Goodyear put this idea (63) the test, and saw that it did have more or less the desired effect though somewhat less than more. The only effect it had was on the outside of the rubber. It is common knowledge now that the (64) to make rubber hard and strong is by heating it with sulfur. It took Goodyear four more years to find this metho D. When at last he did it, he had (65) at all. Everything of the smallest value had been used to get money, even his sons’ school-books.
选项
A、did
B、built
C、tried
D、conducted
答案
A
解析
转载请注明原文地址:https://kaotiyun.com/show/CmQd777K
本试题收录于:
职称英语理工类C级题库职称英语分类
0
职称英语理工类C级
职称英语
相关试题推荐
EbolaOutbreak1YouarelikelyawarethatseveralcountriesinWestAfricaarebattlinganEbolaoutbreak.Ebolaisadangerous
SleeplessnessInsomniaorsleeplessnessisacommoncomplaintofwomenastheyenterintomenopause.Insomniameanshavingt
SleeplessnessInsomniaorsleeplessnessisacommoncomplaintofwomenastheyenterintomenopause.Insomniameanshavingt
AnExcitingNewWorldOpeningtoCivilianScientistsItishardtotrackthebluewhale,theocean’slargestcreature,which
ASpecialClockEverylivingthinghaswhatscientistscallabiologicalclockthatcontrolsbehavior.Thebiologicalclock(5
FlyingintoHistoryWhenyouturnonthetelevisionorreadamagazine,celebrities(名人)areeverywhere.Althoughfameandt
LifeintheUniverseManyscientiststodayareconvincedthatlifeexistselsewhereintheuniverse-lifeprobablymuchlike
Theoriesofteachinghavenotbeenasfullydevelopedashavetheoriesoflearning.
Allgasesandmostliquidsandsolidsexpandwhenheated,buttheydonotexpandequally.
随机试题
原定正常的施工条件具体包括()。
下列有关酶和辅酶(或辅基)的叙述,正确的是
丁香柿蒂汤的组成药物不包括
施工期间,需要进行价格调整的材料,承包人在采购前应将材料单价和采购数量报发包人核对,发包人应在()个工作日内予以答复,否则视为已经认可。
有关培训考核评估制度的说法错误的是()。
原发性肝癌患者不适宜手术的指征是()。
关于接受学习,下列说法正确的是()。
流体在流动过程中,流速大的地方,压强小;流速小的地方,压强大。当固体与流体有相对运动时,物体除受到一定阻力外,有时还可能受到与相对速度方向垂直的力。运动员在足球比赛中发角球时,可以发出“香蕉球”——球飞到球门前方时会拐弯进入球门,如图(俯视)所示,这是因为
某单位周一至周五为工作日,周六、周日双休,某年7月份,该单位员工小刘共出勤22天(全勤),则该年的7月8日可能为:
Tous,itseemssonaturaltoputupanumbrellatokeepthewateroffwhenitrains.Butactuallytheumbrellawasnotinvented
最新回复
(
0
)