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
考研
Sunlight is free, but that is no reason to waste it. Yet even the best silicon solar cells—by far the most【C1】________sort—conve
Sunlight is free, but that is no reason to waste it. Yet even the best silicon solar cells—by far the most【C1】________sort—conve
admin
2022-01-04
24
问题
Sunlight is free, but that is no reason to waste it. Yet even the best silicon solar cells—by far the most【C1】________sort—convert only a quarter of the light that falls on them. Silicon has the【C2】________of being cheap: manufacturing improvements have brought its price to a point where it is snapping at the heels of fossil fuels.【C3】________many scientists would like to replace it【C4】________something fundamentally better.
John Rogers, of the University of Illinois, Urbana-Champaign, is one. The cells he has【C5】________can convert 42.5% of sunlight.【C6】________improved, Dr Rogers reckons, their efficiency could rise to 50%. Their【C7】________is that they are actually not one cell, but four, stacked one on top of another.
Solar cells are made of semiconductors, and every type of semiconductor has a【C8】________called a band gap that is different from that of other semiconductors. The band gap【C9】________the longest wavelength of light a semiconductor can absorb (it is transparent to longer wavelengths). It also fixes the【C10】________amount of energy that can be【C11】________from shorter wavelength. The result is that long-wavelength photons are lost and short-wave ones incompletely utilised.
Dr Rogers【C12】________this by using a different material for each layer of the stack. He chooses his materials【C13】________the bottom of the band gap of the top layer matches the top of the band gap of the one underneath, and so on【C14】________the stack. Each layer thus【C15】________off part of the spectrum, converts it efficiently into electrical energy and passes the rest on.
The problem is that the materials needed to make these semiconductors are【C16】________But Dr Rogers has found a way to overcome this.【C17】________solar-cell modules are completely covered by semiconductor, but in his only 0.1% of the surface is so covered. The semiconducting stacks, each half a millimeter square, are【C18】________over that surface many dots. Each stack then has a pair of cheap glass lenses【C19】________over it. These focus the sun’s light onto the stack, meaning that all【C20】________light meets a semiconductor.
【C12】
选项
A、gets along
B、gets off
C、gets through
D、gets round
答案
D
解析
上段最后一句指出传统的太阳能电池的缺点。空格后的指代词this指代前一段所提到的缺点。而by后面提到Rogers博士通过每一层使用不同的材料来……,显然是要解决前一句的问题。D项gets round意为“避开”,符合句意。A项gets along意为“进展”,不接宾语。B项gets off意为“离开”。C项gets through意为“完成”。这三项均不能表达“解决问题”之意。
转载请注明原文地址:https://kaotiyun.com/show/HZY4777K
0
考研英语二
相关试题推荐
Amajorreasonforconflictintheanimalworldisterritory.Themaleanimal(21)anarea.Thesizeoftheareaissufficientt
Amajorreasonforconflictintheanimalworldisterritory.Themaleanimal(21)anarea.Thesizeoftheareaissufficientt
Amajorreasonforconflictintheanimalworldisterritory.Themaleanimal(21)anarea.Thesizeoftheareaissufficientt
Amajorreasonforconflictintheanimalworldisterritory.Themaleanimal(21)anarea.Thesizeoftheareaissufficientt
Amajorreasonforconflictintheanimalworldisterritory.Themaleanimal(21)anarea.Thesizeoftheareaissufficientt
Thosedaysarelonggonewhenplacingatelephonecallmeantsimplypickingupthereceiverandaskingtheoperatortopatchyou
Thosedaysarelonggonewhenplacingatelephonecallmeantsimplypickingupthereceiverandaskingtheoperatortopatchyou
Notsolongago,itwasthestuffofnightmares:youpickupthelandlinetelephoneandthere’snodialingtone.Nothing.Theph
Notsolongago,itwasthestuffofnightmares:youpickupthelandlinetelephoneandthere’snodialingtone.Nothing.Theph
随机试题
字长为16位的某计算机,其主存容量为64KB,采用单字长单地址指令,共有64条指令。请解决以下问题:(1)系统采用立即寻址,请给出指令的设计格式。(2)系统采用直接寻址,请给出指令的设计格式。(3)系统采用基址寻址,请给出指令的设计格式。(4)系
下列是软膏剂类脂类基质的是()
根据《中华人民共和国招标投标法》,可以不采用法定招标方式确定承包人的项目是()。
A公司和B公司签订一项购销合同,A公司向B公司开出发票后1个月付款的银行汇票。B公司将汇票背书后向C公司转让,C公司又背书后向D公司转让。请根据现行法规,回答下列问题。如果B公司未履行供货义务,A公司有权利要求银行停止支付该汇票吗?
甲公司2009年支付4000万元取得20万平方米土地使用权,新建厂房建筑面积8万平方米,工程造价1800万元,2010年12月完工并通过验收。该企业计算2011年房产税时的正确处理有()。(注:当地按房产原值一次扣除30%后的余值计税)。
贯彻因材施教,教师应针对学生的特点来进行有区别的教学。对于学习不专心的同学,以下最适合采取的教学方法是()
新闻媒体应该正确传递各方声音,起到公众与政府互动的_______作用;应该继承、扬弃、整合和创造文化形态,_______地影响和塑造社会大众的精神操守,提升民族文化的层次和品位。填入横线部分最恰当的一项是()。
当在消毒柜中消毒时,不含水分的餐盘包括其内部,可以达到很高的、足以把所有引起餐盘中毒的细菌杀死的温度;但是含有水分的餐盘的内部则达不到这样高的温度。由上述断定不能推出的结论是哪项?
在中国共产党的领导下,走中国特色社会主义道路,实现中华民族伟大复兴,是现阶段我国各族人民的共同理想。这个共同理想
WefeedbirdsforthefollowingreasonsEXCEPTthat
最新回复
(
0
)