Batteries can power anything from small sensors to large systems．While scientist

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

“To provide enough power, we need certain methods withhigh energy density（密度）”，said JaeKwon, 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 onbuilding a small nuclear battery, presently the size and thickness of a penny,intended to power various micro / nanoelectromechanical systems （M/NEMS）．Although nuclearbatteries can cause concerns, Kwon said they are safe．

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

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

“The key part of using a radioactive battery is thatwhen you harvest the energy, part of the radiation energy can damage thelattice 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 isworking to build and test the battery．In thefuture, they hope to increase the battery’s power, shrink its size and try withvarious other materials．Kwon said that battery could be thinnerthan the thickness of human hair

1.The text is most probably a ________．

A．science newsreport                   B．book review

C．newspaper ad                    D．science fiction

2.Liquid semiconductor is used to _________．

A．get rid of theradioactive waste

B．test the power of nuclearbatteries

C．decrease the size ofnuclear batteries

D．reduce the damage tolattice structure

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

A．uses a solidsemiconductor        B．will soon replace the present ones

C．could be extremelythin              D．has passed the final test

4.Jae Kwon gave examples in Paragraph 4_________．

A．to show chemicalbatteries are widely applied

B．to introduce nuclearbatteries can be safely used

C．to describe anuclear-powered system

D．to introduce variousenergy sources

试题答案

【答案】

1.A

2.D

3.C

4.B

【解析】

试题