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Nanotechnology, according to its fans, will jump-start a new industrial revolution with molecular-sized structures as complex as the human cell and 100 times stronger than steel. The new technology transforms everyday products and the way they are made by manipulating atoms so that materials can be shrunk, strengthened and lightened all at once. To date only modest nanotech-based products—such as stain-resistant fabrics and fresh food packaging—have entered the market, but some scientists predict nanotechnology will eventually be the only game in town. 'It will be a ubiquitous technology,' said George Stephanopoulos, professor of chemical engineering at the Massachusetts Institute of Technology. He echoes other nanotech supporters who say industrial countries are already sliding toward its use in every aspect of manufacturing. Aided by recent advances in microscopes, scientists can now place single atoms where they want for the first time. The potential applications are numerous, with microscopic computers, cancer-killing antennae and nonpolluting car engines on the distant horizon. When it's all going to happen, though, is another matter. According to most scientific accounts, the nanotech future may be 10 to 20 years off. Major hurdles need to be jumped. First, there is a lack of economic mass production. Some of the more complicated devices would require exact placement of billions of atoms. 'It may take the lifetime of the universe to complete the construction of (such a) device,' said George Barbastathis, assistant professor at MIT. Another challenge is bridging the nanoscale and macroscopic, he said. In other words, the smallness of a nano device is useless when it must be attached to large wires. It's unclear how scientists will overcome these problems. And fears derived from science fiction threaten to derail nanotechnology even as it emerges, in much the same way popular anxiety over 'super-weeds' and 'frankenfoods' have hobbled biotechnology in agriculture and fear of 'designer babies' has set back stem-cell research. Lured by a market with billions of dollars in potential profits, giants like GE, Intel, Motorola and IBM are already heavily involved in research. Worldwide, the two industries with the potential to win big with nanotechnology are electronics and biotechnology, according to MIT researchers. On the biotech front, scientists are promoting the notion of nanoparticles made from gold that could be triggered remotely to heat and kill individual cancer cells. Nanotechnology holds equal promise for wealth creation, hut there isn't a consensus among venture capitalists on how to realize it. 'Which direction is it going to work out in? That's the question on everyone's mind,' Gang Chen, an associate professor at the MIT, told scientists at a Boston nano gathering. The statement '… be the only game…' (line 7, Para. 1) implies that______.
A.
nanotechnology can not continue in existence for a long time
B.
nanotechnology will be the only activity that provides entertainment
C.
nanotechnology will become the most influential in the future
D.
nanotechnology will become the most beneficial thing someday
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正确
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错误
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正确
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学生和成绩
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成绩和课程
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学生和课程
D.
学生、成绩和课程
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预计资产负债表
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A.
between 90 and 100
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>=90 and <=100< /div>
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肾功能
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脑电图
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腹部B超
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血气分析
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X线胸片
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