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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 cells 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 poc
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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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 cells 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 poc
A. They had trouble keeping enzymes in fuel cells active.
B. They had trouble keeping biological cells active.
C. They had trouble producing fresh enzymes.
D. They had trouble finding mechanism for producing enzymes.

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[单项选择]Arecent study of drivers using cell phones has reported that accidents are four times as likely, even if a driver is using a hands-free telephone. This study, the first of its kind to compare extensive data about accidents and cell phone records, draws a direct link between the risk of traffic accidents and general phone use while driving.
The findings show that the use of earpieces and other hands-flee telephone devices while driving does not reduce the risk of an accident. The research concludes that the primary cause of phone-related accidents is not the handling of the phone, but rather the act of talking on a phone.
"The brain cannot adequately process the complex information required for driving and talking on the phone at the same time," according to Guiseppe Fontini, a leading researcher in cognitive sciences. "This information overload distracts the driver and makes him less alert, thus leading to a serious compromise." And possibly a serious accident.
The chall
A. Driver’s license requirements
B. The latest cell phone technology
C. Internet telephone services
D. Cell phone use while driving

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[简答题]Part 1Mobile Phones Do you use a cell phone What do you use it for How often do you use it Do you like to send short message When did you get your first mobile phone How did you feel when you got your first mobile phone What feature or function of your cell phone do you like the best Is there anything you dislike about using cell phones

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The safety of mobile phones (U. S. cell-phones) seems to face new questions after British researchers found that microwave emissions can affect the health of earthworms in unexplained ways.
The larvae of tiny soil worms called nematodes grew faster and became more (1) after they were (2) for a long time to weak microwave radiation, of the (3) strength and frequency as that (4) by mobile phones, they found.
Why this occurred is (5) , and there is no evidence that human health is also affected. But, they warn, the finding challenges the standards which (6) whether a mobile is safe or not.
These standards are based on whether the radiation is strong enough to cause a batch of (7) to warm up. Heat causes the chemical bonds in cells to (8) , a disruption that can be a potential (9) for cancer.
The research, led by David de Pomerai at Nottingham University, central England, s
A. without
B. with
C. despite
D. unless

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