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【单选题】
Sugar Power for Cell Phones Using enzymes commonly found in living cells, a new type of fuel cell produces small amounts of electricity from sugar. If the technology is able to succeed in mass production, you may some day share your sweet drinks with your cell phone. In fuel cells, chemical reactions generate electrical currents. The process usually relies on precious metals, such as platinum. In living cells, enzymes perform. a similar job, breaking down sugars to obtain electrons and produce energy. When researchers previously used enzymes in fuel cells, they had trouble keeping them active, says Shelley D. Minteer of St Louis University. Whereas biological cells continually produce fresh enzymes, there's no mechanism in fuel ceils to replace enzymes as they quickly degrade. Minteer and Tamara Klotzbach, also of St Louis University, have now developed polymers that wrap around an enzyme and preserve it in a microscopic pocket. 'We tailor these pockets to provide the ideal microenvironment' for the enzyme, Minteer says. The polymers keep the enzyme active for months instead of days. In the new fuel cell, tiny polymer bags of enzyme are embedded in a membrane that coats one of the electrodes. When glucose from a sugary liquid gets into a pocket, the enzyme oxidizes it, releasing electrons and protons. The electrons cross the membrane and enter u wire through Which they travel to the other electrode, where they react with oxygen in the atmosphere to produce water. The flow of electrons through the wire constitutes an electrical current that can generate power. So far, the new fuel cells don't produce much power, but the fact that they work at all is exciting, says Paul Kenis, a chemical engineer at the University of Illinois at Urbana-Champaign. 'Just getting it to work,' Kenis says, 'is a major accomplishment.' Sugar-eating fuel cells could be an efficient way to make electricity. Sugar is easy to find. And the new fuel cells that mn on it are biodegradable,, so the technology wouldn't hart the environment. The scientists are now trying to use different enzymes that will get more power from sugar. They predict that popular products may be using the new technology in as little as 3 years. According to the first paragraph, when can we share our sweet drinks with our cell phones?
A.
When enzymes can be commonly found in living cells.
B.
When the technology of producing a new type of fuel cell appears.
C.
When the technology of a new type of fuel cell is suitable for mass production.
D.
When the technology of mass producing cell phones appears.
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举一反三
【单选题】_______ I work with my classmates after school.
A.
Sometimes
B.
Some times
C.
Sometime
D.
Some time
【多选题】期货公司有关联关系的股东持股比例合计达到5%的,持股比例最高的股东应当符合下列()条件。
A.
近5年内未因违法违规经营受到行政处罚或者刑事处罚
B.
未因涉嫌违法违规经营正在被有权机关立案调查或者采取强制措施
C.
在近5年内作为金融机构的股东或者实际控制人,或者作为上市公司的控股股东或者实际控制人,没有滥用股东权利、逃避股东义务等不诚信行为
D.
其自然人股东、法定代表人或者高级管理人员没有被采取证券、期货市场禁入措施,或者禁入期限届满已逾2年;没有被撤销证券、期货高级管理人员任职资格或者从业人员资格,或者自被撤销之日起已逾2年;不存在《公司法》第一百四十七条第一款所列情形
【判断题】启动发动机后,应等5-10分钟才会有暖风
A.
正确
B.
错误
【单选题】先用酚妥拉明,再用肾上腺素,血压的变化是
A.
上升
B.
下降
C.
先升后降
D.
不变
【单选题】给予酚妥拉明后再应用肾上腺素,血压的变化是
A.
下降
B.
上升
C.
不变
D.
先升后降
E.
先降后升
【单选题】在动物血压试验中,静脉注射肾上腺素,血压先升高后稍下降,注射酚妥拉明后,再次重复静脉注射肾上腺素,该血压变化是()
A.
药物作用消失,血压无变化
B.
升压作用、降压作用均减弱
C.
升压作用消失,翻转为明显的降压
D.
药物作用不受影响
E.
升压作用、降压作用均增强
【单选题】( )用稀硫酸处理后,置紫外光灯下(365nm)检视,显天蓝色荧光的是
A.
艾司唑仑
B.
氯硝西泮
C.
苯妥英钠
D.
硫喷托纳
E.
奥沙西泮
【单选题】在上市公司收购中,适用简易程序免于发出要约收购方式增持股份的事项不包括下列( )项。
A.
经政府或者国有资产管理部门批准进行国有资产无偿划转、变更、合并,导致投资者在一个上市公司中拥有权益的股份占该公司已发行股份的比例超过30%
B.
因上市公司按照股东大会批准的确定价格向特定股东回购股份而减少股本,导致当事人在该公司中拥有权益的股份超过该公司已发行股份的30%
C.
证券公司、银行等金融机构在其经营范围内依法从事承销、贷款等业务导致其持有一个上市公司已发行股份超过30%,没有实际控制该公司的行为或者意图,并且提出在合理期限内向非关联方转让相关股份的解决方案
D.
在一个上市公司中拥有权益的股份达到或者超过该公司已发行股份的30%的,自上述事实发生之日起一年后,每12个月内增持不超过该公司已发行的2%的股份
【单选题】先给动物酚妥拉明,再用肾上腺素,对血压的影响是
A.
血压先降低后升
B.
血压先升后降
C.
血压无变化
D.
血压明显升高
E.
血压下降
【判断题】三态缓冲门可组成运算器的数据总线,它的输出电平有逻辑“1”、逻辑“O”、空三种状态。( )
A.
正确
B.
错误
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