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 nanotechnology, Yet over the past year also, a series
If you are a fan of science fiction, you’ve no doubt encountered the term nanotechnology, Yet over the past year also, a series
admin
2014-03-02
73
问题
If you are a fan of science fiction, you’ve no doubt encountered the term nanotechnology, Yet over the past year also, a series of breakthroughs have transformed nanotech from sci-fi fantasy into a real-world. Applied science, and 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 fight. 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 super-computer 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 ceils 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 macromolecules 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.
It can be inferred that Richard Feynman has been ______ now.
选项
A、dead
B、decent
C、prominent
D、popular
答案
A
解析
第2段中说late physicist Richard Feynman,late是“已故的”意思,也就是说Richard Feynman已经死了。所以选A。
转载请注明原文地址:https://kaotiyun.com/show/XjQO777K
0
考博英语
相关试题推荐
"Interculturalcommunication"iscommunication【51】membersofdifferentcultures.Thisdefinitionissimple,【52】theprocessisco
WhenIdecidedtoquitmyfulltimeemploymentitneveroccurredtomethatImightbecomeapartofanewinternationaltrend.
Sincethereissuchanabundanceoffoodinthesea,itisunderstandablethatsomeoftheefficient,highlyadaptable,warm-blo
Thisspeculation(acoursetaughtwithtechnologyhelpsstudentslearnmorethantheonetaughtintheliveclassroom)isnotbase
Howeverimportantwemayregardschoollifetobe,thereisnogainsayingthefactthatchildrenspendmoretimeathomethanin
WhenDonaldarrivedforhisfirstgroup-therapysessionhewasinawheelchair,sufferingfrommalignantmelanomaandseverelyd
Thereisapicturebelow.Lookatitcarefullyandwriteacompositionofabout250wordscommentingonwhatitconveys.Remembe
Weshouldalwaysbearinmindthat______decisionsoftenresultinseriousconsequences.
Consumersandproducersobviouslymakedecisionsthatmoldtheeconomy,butthereisathirdmajor【1】toconsidertheroleofgov
IworkasanofficeassistantinasmallbutgrowinggardenequipmentmanufacturingcompanyinCalifornia.Afewmonthsago,my
随机试题
信用是指经济活动中的一种借贷行为,是以偿还和付息为条件的价值()让渡。
基金销售机构对于所属已获得基金销售资格的从业人员,应参照()的要求,组织与基金销售相关的职业培训。
A.超范围开展计划生育服务B.刊登、广播计划生育服务广告C.三年中两年计划生育手术量未超过50例D.人员未能达到技术要求而开展计划生育技术服务E.发生计划生育技术服务三级医疗事故《计划生育技术服务管理规范》规定暂缓3个月校验的情况有
临床上最常出现血尿的疾病是
A.1年B.2年C.3年D.5年E.10年医疗用《麻醉药品购用印鉴卡》的有效期限为
旅行社申报或登记的企业名称,应当符合企业名称登记管理的有关规定,并须含有“旅行社”字样。()
论述企业销售物流合理化的途径。
随着“二孩”政策全面放开,使得托儿所、幼儿园的人数不断增加,学前教育资源相对不足,假如你是教育部的工作人员,要针对此情况做一个调研报告,请问你会如何开展?
你试着在两项投资中进行选择,二者的投资成本都为75000美元。C投资在5年内每年将产生135000美元的回报。H投资在10年内每年的回报额则为195000美元。请问这两项投资哪个收益率更高?
TherearemanytheoriesaboutthebeginningofdramainancientGreece.Theonemost(1)______acceptedtodayisbasedontheass
最新回复
(
0
)