首页
登录
职称英语
While chemists try to assemble molecules using a combination of theor
While chemists try to assemble molecules using a combination of theor
游客
2024-01-11
20
管理
问题
While chemists try to assemble molecules using a combination of theoretical
principles and practical experience to mold molecules that have desired
structural and chemical properties, nanotechonologists generally seek to make
Line more than a single molecule. They build arrays of identical or complexed
(5) molecules, sometimes on a scale that will transcend the boundaries of the
microscopic and approach the macroscopic, using both top-down and bottom-up
approaches. The first is exemplified by scientists who build objects and
molecular arrays using the techniques of scanning probe microscopy, while the
second is exemplified by investigators who design two-and three-dimensional
(10) chemical systems that cohere according to the rules of chemical interactions.
The top-down approach has exquisite precision, but its disadvantage is its lack
of extensive parallelism; it requires manipulating atoms and molecules
practically one by one, while the bottom-up approach is massively parallel. But
in both cases, scientists are forced to use the difficult nanometer scale, i.e. the
(15) level at which living systems tend to make their structural components, rather
than the angstrom scale of chemistry. [br] The primary purpose of the passage is to
选项
A、indicate some possible technological benefits to the development of new and varied techniques in nanotechnology
B、argue that science involving the macroscopic tends to be exponentially more difficult than the science of the microscopic
C、defend the use of the bottom-up approach of building molecules as more efficient relative to the top-down approach
D、distinguish two different approaches in nanotechnology and comment on their differences and similarities
E、correct the misconception that the benefits of nanotechnology are likely to be seen in the near future
答案
D
解析
转载请注明原文地址:https://tihaiku.com/zcyy/3353523.html
相关试题推荐
11.Anycombinationofoverworkandstressinevitablyleadsofinsomnia.Manage
LikeJohnMcPhee’sworks,AnnBeattiepainstakinglyassemblesinherworksanin
Whilechemiststrytoassemblemoleculesusingacombinationoftheor
Whilechemiststrytoassemblemoleculesusingacombinationoftheor
Whilechemiststrytoassemblemoleculesusingacombinationoftheor
Whilechemiststrytoassemblemoleculesusingacombinationoftheor
AMALGAMATE:A、revitalizeB、stratifyC、segregateD、assembleE、insulateC
Sometimesthecombinationofseveral(i)______improvementscreatesanoverallimp
Bodylanguageinvolvesacombinationofmultiplefacial(i)______andvariousphy
Thecombinationof(i)____and(ii)____inEdmund’sspeechcanbestartling,esp
随机试题
WhichofthefollowingsentencesexpressesWILLINGNESS?A、Wewillneverdoitaga
()标准适用于数据传输速率为1.5Mbps的数字存储媒体运动图像及伴音编码。A.
甲欲杀乙,在乙家户外菜同的蔬菜中下毒。甲明知乙及其妻子每天都会食用这些蔬菜,但由
在建筑室内照度低的部位,色彩的效果随色相不同而改变,其中显明亮的色彩是:()
全科医生提供预防服务的途径不包括A.开展健康教育及健康促进 B.参与公共卫生服
紫苏叶的来源为A.唇形科紫苏的叶B.豆科紫苏的叶C.蔷薇科紫苏的叶D.茄科紫苏的
下列有关交叉口交通组织方式的表述,哪项是错误的?()A.在交通量较大的交叉口
学生的主观能动性有三个层次,其最基本的表现是() A.自觉性B.独立性C
与体表化脓感染相关的肝脓肿的常见致病菌是( )。A.大肠埃希菌 B.双歧杆菌
编制人工定额时,拟定正常的施工作业条件包括()。A.拟定施工作业的内容 B.拟
最新回复
(
0
)