Rats that eat high levels of a natural sugar known as fructose（果糖） seem to age faster than other rats--and the same could be true for people who eat too much sweet junk food, Israeli researchers said Monday.
　　Fructose, found naturally in honey and fruit, is used widely in foods ranging from soft drinks to yogurt（酸奶）. But while its sweet taste is popular, the sugar could cause wrinkles and health problems, the researchers said. Dr. Moshe Werman and Boaz Levi of the Technion-Israel Institute of Technology fed large amounts of fructose to laboratory rats. Writing in the Journal of Nutrition, they said the fructose-fed rats showed changes in the collagen（胶原蛋白）of their skin and bones.
　　Collagen, a fibrous protein found in connective tissue, bone and cartilage, basically holds the body together. The loss of collagen is what causes loose skin and deep wrinkles in older people.
　　The process affected, Werman's team said, is known as "cross linking". "Too much cross-linking reduces flexibility(弹性) and makes the skin stiff and rigid, and these are the conditions that encourage wrinkled skin," Werman said in a statement. He said the same could be true of people, although this has not been shown. "Americans are eating more and more processed foods, such as carbonated drinks, baked goods, canned fruits, jams and dairy products that contain fructose，than Asian people," Werman said. Other studies have shown that high fructose intake can affect how the body handles glucose and increases insulin resistance——which can both be important measures of the tendency toward diabetes(糖尿病).　　

The rats Werman worked with were fed much more than the average adult person might eat in a day, which is standard in such experiments. The rats were fed 12.5 grams of fructose per kg (2.2 pounds) of weight every day for a year. To compare, a person weighing 154 pounds (70kg) who drinks a quart (liter) of cola consumes about 60 grams of fructose, or 0.8 grams per kg of body weight.

60.If people eat too much fructose, they may have the following signs EXCEPT________.

A. loose skin     B. deep wrinkles     C. a sweet tooth      D. aging faster

61.According to the passage, diabetes is diagnosed (诊断) mainly by measuring________.

  A. the amount of fructose eaten         B. the loss of collagen

  C. the cross linking                  D. glucose and insulin resistance

62. What can we infer from the passage? ________

A. Americans are easier to have diabetes than Asians.

  B. Diabetes can only be controlled, not cured.

  C. People eating too much fructose must have health problems.

  D. It’s abnormal to feed more fructose to the rats than an adult in the experiment.

Batteries can power anything from small sensors to large systems．While scientists are finding ways to make them smaller but even more powerful, problems can arise when these batteries are much larger and heavier than the devices themselves．University of Missouri（MU） researchers are developing a nuclear energy source that is smaller, lighter and more efficient．
“To provide enough power, we need certain methods with high energy density（密度）”，said Jae Kwon, assistant professor of electrical and computer engineering at MU．“The radioisotope（放射性同位素） battery can provide power density that is much higher than chemical batteries．”
Kwon and his research team have been working on building a small nuclear battery, presently the size and thickness of a penny, intended to power various micro / nanoelectromechanical systems （M/NEMS）．Although nuclear batteries can cause concerns, Kwon said they are safe．
“People hear the word ‘nuclear’ and think of something very dangerous,” he said, “However, nuclear power sources have already been safely powering a variety of devices, such as pace-makers, space satellites and underwater systems．”
His new idea is not only in the battery’s size, but also in its semiconductor（半导体）．Kwon’s battery uses a liquid semiconductor rather than a solid semiconductor．
“The key part of using a radioactive battery is that when you harvest the energy, part of the radiation energy can damage the lattice structure（晶体结构） of the solid semiconductor,” Kwon said, “By using a liquid semiconductor, we believe we can minimize that problem．”
Together with J．David Robertson, chemistry professor and associate director of the MU Research Reactor, Kwon is working to build and test the battery．In the future, they hope to increase the battery’s power, shrink its size and try with various other materials．Kwon said that battery could be thinner than the thickness of human hair．
【小题1】Jae Kwon gave examples in Paragraph 4_________．

A．to show chemical batteries are widely applied．

B．to introduce nuclear batteries can be safely used．

C．to describe a nuclear-powered system．

D．to introduce various energy sources．

【小题2】According to Jae Kwon, his nuclear battery _______．

A．uses a solid semiconductor	B．will soon replace the present ones．
C．could be extremely thin	D．has passed the final test．

【小题3】The text is most probably a ________．

A．science news report	B．book review
C．newspaper ad	D．science fiction

Batteries can power anything from small sensors to large systems．While scientists are finding ways to make them smaller but even more powerful, problems can arise when these batteries are much larger and heavier than the devices themselves．University of Missouri（MU） researchers are developing a nuclear energy source that is smaller, lighter and more efficient．

“To provide enough power, we need certain methods with high energy density（密度）”，said Jae Kwon, assistant professor of electrical and computer engineering at MU．“The radioisotope（放射性同位素） battery can provide power density that is much higher than chemical batteries．”

Kwon and his research team have been working on building a small nuclear battery, presently the size and thickness of a penny, intended to power various micro / nanoelectromechanical systems （M/NEMS）．Although nuclear batteries can cause concerns, Kwon said they are safe．

“People hear the word ‘nuclear’ and think of something very dangerous,” he said, “However, nuclear power sources have already been safely powering a variety of devices, such as pace-makers, space satellites and underwater systems．”

His new idea is not only in the battery’s size, but also in its semiconductor（半导体）．Kwon’s battery uses a liquid semiconductor rather than a solid semiconductor．

“The key part of using a radioactive battery is that when you harvest the energy, part of the radiation energy can damage the lattice structure（晶体结构） of the solid semiconductor,” Kwon said, “By using a liquid semiconductor, we believe we can minimize that problem．”

Together with J．David Robertson, chemistry professor and associate director of the MU Research Reactor, Kwon is working to build and test the battery．In the future, they hope to increase the battery’s power, shrink its size and try with various other materials．Kwon said that battery could be thinner than the thickness of human hair．

1.Jae Kwon gave examples in Paragraph 4_________．

A．to show chemical batteries are widely applied．

B．to introduce nuclear batteries can be safely used．

C．to describe a nuclear-powered system．

D．to introduce various energy sources．

2.According to Jae Kwon, his nuclear battery _______．

A．uses a solid semiconductor                B．will soon replace the present ones．

C．could be extremely thin                  D．has passed the final test．

3.The text is most probably a ________．

A．science news report                     B．book review

C．newspaper ad                          D．science fiction

 

Batteries can power anything from small sensors to large systems．While scientists are finding ways to make them smaller but even more powerful, problems can arise when these batteries are much larger and heavier than the devices themselves．University of Missouri（MU） researchers are developing a nuclear energy source that is smaller, lighter and more efficient．

“To provide enough power, we need certain methods with high energy density（密度）”，said Jae Kwon, assistant professor of electrical and computer engineering at MU．“The radioisotope（放射性同位素） battery can provide power density that is much higher than chemical batteries．”

Kwon and his research team have been working on building a small nuclear battery, presently the size and thickness of a penny, intended to power various micro / nanoelectromechanical systems （M/NEMS）．Although nuclear batteries can cause concerns, Kwon said they are safe．

“People hear the word ‘nuclear’ and think of something very dangerous,” he said, “However, nuclear power sources have already been safely powering a variety of devices, such as pace-makers, space satellites and underwater systems．”

His new idea is not only in the battery’s size, but also in its semiconductor（半导体）．Kwon’s battery uses a liquid semiconductor rather than a solid semiconductor．

“The key part of using a radioactive battery is that when you harvest the energy, part of the radiation energy can damage the lattice structure（晶体结构） of the solid semiconductor,” Kwon said, “By using a liquid semiconductor, we believe we can minimize that problem．”

Together with J．David Robertson, chemistry professor and associate director of the MU Research Reactor, Kwon is working to build and test the battery．In the future, they hope to increase the battery’s power, shrink its size and try with various other materials．Kwon said that battery could be thinner than the thickness of human hair．

67．The text is most probably a ________．

       A．science news report                                  B．book review   

       C．newspaper ad                                           D．science fiction

68．Liquid semiconductor is used to _________．

       A．get rid of the radioactive waste               B．test the power of nuclear batteries．

       C．decrease the size of nuclear batteries          D．reduce the damage to lattice structure．

69．According to Jae Kwon, his nuclear battery _______．

       A．uses a solid semiconductor                         B．will soon replace the present ones．

       C．could be extremely thin                              D．has passed the final test．

70．Jae Kwon gave examples in Paragraph 4_________．

       A．to show chemical batteries are widely applied．

       B．to introduce nuclear batteries can be safely used．

       C．to describe a nuclear-powered system．

       D．to introduce various energy sources．

       Batteries can power anything from small sensors to large systems．While scientists are finding ways to make them smaller but even more powerful, problems can arise when these batteries are much larger and heavier than the devices themselves．University of Missouri（MU） researchers are developing a nuclear energy source that is smaller, lighter and more efficient．

       “To provide enough power, we need certain methods with high energy density（密度）”，said Jae Kwon, assistant professor of electrical and computer engineering at MU．“The radioisotope（放射性同位素） battery can provide power density that is much higher than chemical batteries．”

       Kwon and his research team have been working on building a small nuclear battery, presently the size and thickness of a penny, intended to power various micro / nanoelectromechanical systems （M/NEMS）．Although nuclear batteries can cause concerns, Kwon said they are safe．

       “People hear the word ‘nuclear’ and think of something very dangerous,” he said, “However, nuclear power sources have already been safely powering a variety of devices, such as pace-makers, space satellites and underwater systems．”

       His new idea is not only in the battery’s size, but also in its semiconductor（半导体）．Kwon’s battery uses a liquid semiconductor rather than a solid semiconductor．

       “The key part of using a radioactive battery is that when you harvest the energy, part of the radiation energy can damage the lattice structure（晶体结构） of the solid semiconductor,” Kwon said, “By using a liquid semiconductor, we believe we can minimize that problem．”

Together with J．David Robertson, chemistry professor and associate director of the MU Research Reactor, Kwon is working to build and test the battery．In the future, they hope to increase the battery’s power, shrink its size and try with various other materials．Kwon said that battery could be thinner than the thickness of human hair．

1．Which of the following is true of Jae Kwon?

       A．He teaches chemistry at MU．

       B．He developed a chemical battery．

       C．He is working on a nuclear energy source．

       D．He made a breakthrough in computer engineering．

2．Jae Kwon gave examples in Paragraph 4_________．

       A．to show chemical batteries are widely applied.

       B．to introduce nuclear batteries can be safely used．

       C．to describe a nuclear-powered system．

       D．to introduce various energy sources．

3．Liquid semiconductor is used to _________．

       A．get rid of the radioactive waste

       B．test the power of nuclear batteries．

       C．decrease the size of nuclear batteries

       D．reduce the damage to lattice structure．

4．According to Jae Kwon, his nuclear battery _______．

       A．uses a solid semiconductor

       B．will soon replace the present ones．

       C．could be extremely thin

       D．has passed the final test．

5．The text is most probably a ________．

       A．science news report                           B．book review

       C．newspaper ad                                   D．science fiction story