题型:阅读理解 题类:常考题 难易度:普通
山东省枣庄市第三中学2018-2019学年高一下学期英语6月月考试卷
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 systems (MNEMS). 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 semi conduct or 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.
Welcome to Holker Hall & Gardens
Visitor Information
How to Get to Holker
By Car: Follow brown signs on A590 from J36, M6. Approximate travel times: Windermere—--20 minutes, Kendal—--25 minutes, Lancaster—-45 minutes, Manchester—--1 hour 30 minutes.
By Rail: The nearest station is Cark-in-Carmel with trains to Carnforth, Lancaster and Preston for connections to major cities & airports.
Opening Times
Sunday—Friday (closed on Saturday) 11:00am —4:00pm, 30th March –2nd November. Admission Charges
Hall & Gardens |
Gardens |
|
Adults: |
£ 12.00 |
£ 8.00 |
Groups |
£ 9.00 |
£ 5.50 |
Special Events
Producers' Market 13th April
Join us to taste a variety of fresh local food and drinks. Meet the producers and get some excellent recipe ideas.
Holker Garden Festival 30th May
The event celebrates its 22nd anniversary with a great show of the very best of gardening, making it one of the most popular events in gardening.
National Garden Day 28th August
Holker once again opens its gardens in aid of the disadvantaged. For just a small donation you can take a tour with our garden guide.
Winter Market 8th November
This is an event for all the family. Wander among a variety of shops selling gifts while enjoying a live music show and nice street entertainment.
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