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【单选题】
The Wonderful World of Small There's a quiet revolution going on, and its name is nanotechnology. A host of innovations are coming our way. Some seem almost magical, like the new material created in 2004 by Ray Baughman, a professor at the University of Texas. It's stronger than steel, transparent, very, very light. A hectare-size sheet would weigh just 280 grams. When the professor announced that he hadn't decided what to call it, he started to get emails from around the world suggesting names. Since it was so light and strong, people started calling it 'mithril' — the name of a highly prized type of armor used in The Lord of Rings. There are other discoveries too — perhaps not so astounding, but practical and pleasant. Now there are socks that don't get smelly, pants that resist stains, windows that repel dirt and toilets that clean themselves. All this results from exploring the world of the very, very small. Nano comes from the Greek word from dwarf. Usually nanotechnology is defined as the study and manipulation of matter smaller than 100 nanometers (纳米) — that's the scale of things like molecules and viruses. Ten hydrogen atoms pressed together against each other are just one nanometer long. And one million nanometers fit into a millimeter. Hard to grasp? Think of it this way: If everyone in Manila were a nanometer wide, the entire population, standing shoulder to shoulder, would fit on your thumbnail. Stunning Uses of Nanotechnology Like Alice in Wonderland, researchers in Nanoland find themselves in a world where old rules don't apply. Small things behave differently. This is behind several innovations, including the self-cleaning toilet. The toilet bowl is sealed with a super-smooth glaze (涂层) that has microscopic holes under 30 nanometers. Because they're smaller than bacteria or other tiny particles, there's not enough room for dirt to get stuck in the surface. Flushing is basically all the work you have to do. Researchers in Nanoland are also making really, really small things with astonishing properties — like the carbon nanotube. Chris Papadopoulos of the University of Victoria, says, 'The carbon nanotube is the poster boy for nanotechnology.' In your pencil, carbon, in the form. of graphite (石墨), is soft and easily broken. But a carbon nanotube is tough as nails — much tougher in fact. It's very thin sheet graphite that's formed into a tube. These tiny straw-like cylinders, which can be as small as half a nanometer wide, are up to 100 times stronger than steel and six times lighter. They are the hardest, stiffest, strongest materials known and are among the world's best conductors of heat and electricity. They can carry some 1,000 times more electricity current than copper wire: Everybody wants them, but until now they've been in short supply and pricey. The current annual production, worldwide, is only 300 kilograms. At $ 860 a gram, carbon nanotubes cost 50 times more than gold. When it comes to finding uses for carbon nanotubes, the range is huge. The National Research Council Canada (NRC) is looking at harnessing their strength by embedding them in construction materials, among other applications. The Boeing Company thinks nanotubes may be the source of futute improvements for high-performance aircraft. Some of the most stunning uses come out of Ray Baughman's research. Employing what he calls the 'ancient technology of spinning', Baughrnan and his team developed a way of spinning carbon nanotubes into fibers that are four times tougher than spider silk, the toughest natural filament (细丝). Since they also conduct electricity, the futuristic yarns could be woven into 'smart' clothing that stores electricity, is potentially bulletproof and incorporates sensors capable of adjusting the temperature of garment. The fibers could also be made into cables for suspension bridges much long
A.
Y
B.
N
C.
NG
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【单选题】下列除哪项外均是胎盘剥离征象( )
A.
子宫缩小,宫底下降
B.
宫体变硬呈球形
C.
阴道少量出血
D.
压耻骨联合上方外露脐带不回缩
E.
外露脐带自行延长
【单选题】药品说明书上采用的名称
A.
商品名
B.
通用名
C.
两者都是
D.
两者都不是
【多选题】领导的构成要素主要包括( )
A.
协调
B.
指挥
C.
激励
D.
感召
E.
造势
【单选题】除下列哪项外均是胎盘剥离的征象( )
A.
阴道少量流血
B.
压迫耻骨联合上方,脐带回缩
C.
宫底升高
D.
外露之脐带下降
E.
宫体变硬成球形
【多选题】下列属于施工期洞口防排水常用处理方法的是______。
A.
平整洞顶地表,排除积水
B.
整理洞顶流水沟渠,注意水池的防渗和防溢
C.
修筑洞口边、仰坡顶外天沟,确保引流,尽早完成洞口、辅助坑道口、井口的排水系统
D.
用钻孔将水集中引入排水沟
【单选题】未曾在中国境内上市销售药品属于
A.
仿制药
B.
进口药
C.
新药
D.
原研药
【单选题】关于代理和寄售的区别表述错误的是( )。
A.
代理商与代销商与委托人的关系都是委托代理或者代销的关系
B.
代理商是零售商的一种,代销商一般是批发商,两者处于不同的流通环节
C.
代理行为产生的法律后果由委托人负责,而代销商有权以自己的名义订立合同,自己处理相应的法律事务
D.
代理商一般不设仓库,商品销售的费用由代理人来承担。代销商一般有自设店面和仓库,以便顾客看样买货、及时成交
【单选题】甲建筑公司为增值税一般纳税人,机构所在地为A市,从事建筑、安装、装饰等多业经营,2020年2月发生如下业务:(1)承包B市一家毛巾生产厂的厂房改造工程,当月竣工结算,工程总价款为6550万元,发生分包支出1550万元,取得分包企业开具的增值税专用发票。(2)承包本市一家钢铁厂的库房建设工程,本月全部完工,建设施工合同中注明工程总价款为1660万元。另外取得对方支付的提前竣工奖135万元。甲建筑公司...
A.
530.63
B.
574.90
C.
739.41
D.
741.23
【单选题】未曾在中国境内上市销售的药品属于
A.
新药
B.
现代药
C.
传统药
D.
国产药品
E.
进口药品
【多选题】领导的构成要素主要包括()
A.
权力或影响力
B.
对人的理解和激励
C.
对事的组织和监控
D.
营造组织气氛建构组织文化
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