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
If you are a fan of science fiction, you’ve no doubt encountered the term nanotechnol-ogy. Yet over the past year also, a series
If you are a fan of science fiction, you’ve no doubt encountered the term nanotechnol-ogy. Yet over the past year also, a series
admin
2017-03-25
59
问题
If you are a fan of science fiction, you’ve no doubt encountered the term nanotechnol-ogy. Yet over the past year also, a series of breakthroughs have transformed nanotech from sci-fi fantasy into a real world. Applied science, in the process, inspired huge investments by business, academia, and government. In industries as diverse as health care, computers, chemicals, and aerospace, nanotech is overhauling production techniques, resulting in new and improved products, some of which may already be in your home or workplace.
The inspiration for nanotech goes back to a 1959 speech by the late physicist Richard Feynman, then a professor at the California Institute of Technology, titled "There’s Plenty of Room at the Bottom. " Four decades later, Chad Mirkin, a Chemistry professor at Northwestern University’s $34 million nanotech center, used a nanoscale device to etch most of Feynman’s speech onto a surface the size of about 10 tobacco smoke particles.
What accounts for the sudden acceleration of nanotechnology? A key breakthrough came in 1990, when researchers at IBM’s Almaden Research Center succeeded in rearranging individual atoms at will. Using a device known as a scanning probe microscope, the team slowly moved 35 atoms to spell the three-letter IBM logo, thus proving Feynman right. The entire Logo was less than three nanometers.
Soon, scientists were not only manipulating individual atoms but "spray painting" with them as well. Using a tool known as a molecular beam epitaxy, scientists have learned to create ultra fine films of specialized crystals, built up one molecular layer at a time. This is the technology used today to build read-head components for computer hard drives.
The next stage in the development of nanotechnology borrows a page from nature. Building a supercomputer no bigger than a speck of dust might seem an impossible task, until one realizes that evolution solved such problems more than a billion years ago. Living cells contain all sorts of nanoscale motors made of proteins that perform myriad mechanical and chemical functions, from muscle contraction to photosynthesis. In some instances, such motors may be re-engineered, or imitated, to produce products and processes useful to humans.
How are these biologically inspired machines constructed? Often, they construct themselves, manifesting a phenomenon of nature known as self assembly. The macromole-cules of such biological machines have exactly the right shape and chemical binding preferences to ensure that when they combine they will snap together in predesigned ways. For example, the two strands that make up DNA’s double helix match each other exactly, which means that if they are separated in a complex chemical mixture, they are still able to find each other easily.
Who proved that Feynman’s concept, "There’s Plenty of Room at the Bottom" was right?
选项
A、Chad Mirkin at Northwestern University.
B、Researchers at Almaden Research Center.
C、Scientists manipulating atoms and "spray painting".
D、A professor at the California Institute of Technology.
答案
B
解析
本题的四个选项中,只有B项为正确答案。这可从文中第三段的“…in 1990,when researchers at…Feynman right.”推知,即在1990年时,IBM的那个研究中心的研究人员取得了突破,能够随心所欲地重排单个分子,从而证明了Feynman理论的正确。
转载请注明原文地址:https://kaotiyun.com/show/4ZGO777K
0
考博英语
相关试题推荐
Thebasiccausesareunknown,althoughcertainconditionsthatmayleadtocancerhavebeen______.
LikenessesofBuddhaarethesedayssocommonplace—thecasualadornmentoffashionablespas,fusionrestaurantsandParisiann
Thedistancebetweentheearthandthesunmaybesaidtobe______.
Assumingthataconstanttravel-timebudget,geographicconstraintsandshort-terminfrastructureconstraintspersistasfundame
Buildingthisroadwill______theconstructionoftenbridges,thenthetotalcostreaches1millionUSDollars.
TheheadquartersofthistextilecompanyisinNewYorkwhileits20______companiesarelocatedindifferentpartsoftheworl
Thesearchforthelostshipmustbe______becauseofpoorweather.
Writealetterofinvitationofabout100wordstoyourclosefriendTom,askinghimtocomeandstayforaweek-endwithyourf
SofarasIknow,MissHannahArendtwasthefirstpersontodefinetheessentialdifferencebetweenworkandlabor.Tobehappy,
Thesecretarywantsto_____allthefileclerkstomakepreparationsforthecompanyChristmasparty.
随机试题
临床上常选用琥珀胆碱进行气管插管,但下列哪些情况不应使用_____。
男性,60岁,排便习惯改变,大便变细、混有粘液脓血1个月。便常规检查可见多数红细胞。首选应做哪项检查
A.风B.火C.燥D.心E.热诸禁鼓栗,如丧神守,皆属于
肾盂结石直径1.2cm,IVP右肾功能正常,轻度积水,输尿管通畅,首选的治疗方法是
一个国家为了详细了解重要的国情国力,通常采用的统计调查方法是()。
如果无保留意见审计报告包含(),也被视为标准审计报告。
甲公司为上市公司,2×15年至2×17年的有关资料如下:(1)2×15年1月1日发行在外普通股股数为82000万股。(2)2×15年6月1日,经股东大会同意并经相关监管部门核准,甲公司以2×15年5月20日为股权登记日,向全体股东每10股发放1.5份认
"Poverty",wroteAristotle,"istheparentofcrime."Butwasheright?Certainly,povertyandcrimeare【C1】______.Andtheidea
作为乙方的系统集成项目经理与其单位高层领导沟通时,使用频率最少的沟通工具是(41)。
在考牛文件夹下创建文件夹NEWS,并设置属性为隐藏并取消存档属性。
最新回复
(
0
)