| 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, 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 A. The two strands making up DNA’s double helix can find each other easily in a complex chemical mixture B. Evolution has solved the problem of building a computer smaller than a speck of dust a long time before C. DNA not only programs cells to replicate themselves but also instructs them how to assemble individual molecules into new materials D. The read-head components for computer hard drives are constructed by means of the technology known as a molecular beam epitaxy [判断题]集装箱提单一般都有这样的规定：“承运人、船长，或其代理人对于事先不知性质而装载的具有易燃、易爆，以及其他危险性的货物，可在卸货前的任何时候、任何地点将其卸上岸，或将其销毁，或消除其危险l生而不予赔偿。”( )
[单选题]101．高血压脑病是指
A.脑栓塞 B.脑血栓形成 C.脑小动脉严重痉挛引起脑水肿 D.脑血管破裂 E.血压急骤增高 [单项选择]
[单选题]下列叙述中错误的是( )
A.使用低电压摄影时,管电压对图像密度的影响大 B.n值随管电压的升高而升高 C.使用高电压摄影时,摄影条件的通融性大 D.使用低电压摄影时,管电压的选择要严格 E.使用低电压摄影时,摄影条件选择要严格 [填空题]当进路上的有关道岔开通位置不对或（ ）未关闭时，防护该进路上的信号机不能开放。
[判断题]政府专职消防员战斗员岗位人员必须是初中或同等以上学历。( )
A.正确 B.错误 [单选题]
用万用表侧电阻时,被测量电路必须()。 A.带电 B.切断电源 C.有电压 D.有电流 [单项选择]下列哪项不是城市轨道交通列车的停站方案？（）
A. 分区停车 B. 站站停车 C. 区段停车 D. 跨站停车 我来回答: 提交
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