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
In the early 1950s the researchers who produced the first clad glass optical fibers were not thinking of using them for communic
In the early 1950s the researchers who produced the first clad glass optical fibers were not thinking of using them for communic
admin
2013-02-27
28
问题
In the early 1950s the researchers who produced the first clad glass optical fibers were not thinking of using them for communications.【46】H______, fiber optics was already a well-established commercial technology when the famous paper by Kao and Hockham,【47】______ (claim) the use of low-loss optical fibers for communication, appeared in 1966. The first low-loss silica fiber was described in【48】______which appeared in October of 1970. The date of this publication is sometimes【49】______(cite) as the beginning of the era of fiber communication. Although this development did receive【50】______ (consider) attention in the research community at the time, it was far from inevitable that a major industry would evolve.
The technological barriers appeared formidable because there were serious doubts as to【51】 wh______these fiber components could ever be produced economically enough, but the market potential was very significant.【52】______(consequence) , research and development activity expanded rapidly, and a number of important issues were【53】re______during the early 1970s. During the middle and late 1970s, the rate of progress towards marketable products accelerated as the emphasis【54】______(shift) from research to engineering. Fibers with losses【55】app______the Rayleigh limit of 2 dB/km at a wavelength of 0. 8 μm were produced.
By 1980 improvement in component performance, cost, and reliability led to major commitments on the part of telephone companies.
选项
答案
However
解析
此处句意发生转折。此句泽为:50年代初期,那些生产出第一批复合玻璃光纤的研究者们尚未考虑将光纤应用到通信中。然而,当1966年Kao和Hockham发表著名论文,提出把低耗光纤应用于通讯中时,纤维光学已经成为一个相当成熟的商业技术了。
转载请注明原文地址:https://kaotiyun.com/show/xgVK777K
本试题收录于:
C类竞赛(非英语专业本科)题库大学生英语竞赛(NECCS)分类
0
C类竞赛(非英语专业本科)
大学生英语竞赛(NECCS)
相关试题推荐
Allofthis________,shestillholdstheideathatthedevelopmentoftheInternetmakespeoplelosetheirsenseofplace.
A、Toencouragepeopletothinkmoreaboutnature.B、Toexplainhowthegreattheorycameout.C、Toshowthenecessityofcellph
A、Itshouldbeforbidden.B、Itisacommonthing.C、Itshouldbekeptsecret.D、Itispopularamongyoungpeople.B女士在句中说,她认为很多人
A、Peoplearehighupinthesky.B、Itisnotanaturalwayoftransport.C、Theflyingspeedisveryfast.D、Peoplehavetostay
A、Pushingmoraleffortsforcurrentsmokers.B、Educatingyoungpeoplenottostartthehabit.C、Raisingthepricesaswellasta
DealingwithLifeAbroadIntroduction.millionsofpeoplegoabroadtowork,studyortravel.symptomsofculture
(1)Menandwomentendtochoosedifferentcareerpaths,andresearchershaveidentifiedthisasthebiggestreasonmenmakemor
随机试题
A.动眼神经B.面神经C.前庭蜗神经D.舌咽神经E.迷走神经迷走神经背核发出纤维参加
为了便于记忆,基于IP地址的计算机,Internet采用了域名系统DNS,给每台主机起了一个域名,其域名结构正确的是()
大病瘥后喜唾久不了了,胸上有寒,当以丸药温之,治宜选用
运动员百米赛跑途中突然闻及左膝撕裂声,然后倒地。查体左膝不能主动伸屈,X线片示髌骨中段骨折,考虑造成骨折的原因是
A、胆碱酯酶抑制药B、M受体阻断药C、α、β受体激动药D、α受体阻断药E、β受体阻断药阿托品属于()。
A.肾上腺素B.特布他林C.雷尼替丁D.氯苯那敏E.奥美拉唑阻断H2受体而治疗消化溃疡的药物是()。
在竣工财务决算表编制过程中,属于资金来源项目的是()。
Excel表格处理操作考试要求:(1)将标题字体设为“楷体”,24磅,加粗,置于表格正上方。(2)计算每个学生的总成绩和平均成绩,分别放入总成绩和平均成绩栏中,平均成绩保留一位小数。(3)为表格添加边框线,外框线为粗线,内框
Whichofthefollowingactivitiesisthemostsuitableforgroupwork?
一些贫困地区之所以贫困,除了地理___________、生存环境恶劣,其实背后也存在___________的贫困。这种贫困既包括不能___________地享受社保、教育、公共设施等,也包括土地、财产权益的诸多限制。填入画横线部分最恰当的一项是:
最新回复
(
0
)