职称英语考试《理工类》章节练习题精选及
答案0517-80
1、Weaving with Light
In the Sierra Madre mountain range of west central Mexico, the native Huichol people live much the way their ancestors did-without electricity. That's because it's too expensive to string power lines to the remote mountain areas where they live. To help support themselves, the Huichol create beautiful artwork. They sell their art in cities hundreds of miles away from their villages. And without electricity, at home or on the road, they can only work during daylight hours. When it gets dark, they must stop whatever they're doing.
Now, a team of scientists, designers and architects is using new technologies to provide the Huichol with light after the sun sets. The scientists technique involves weaving tiny electronic crystals into fabrics that can be made into clothes, bags, or other items.
By collecting the sun's energy during the day, these lightweight fabrics provide bright white light at night. Their inventors have
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named the fabrics \Lights,\Portable Lights have the potential to transform the lives of people without electricity around the world, says project leader Sheila Kennedy.
\invention,\Kennedy says, \from seeing how we could transform technology we saw every day in the United States and move it into new markets for people who didn't have a lot of money.\
At the core of Portable Light technology are devices called high - brightness light - emitting diodes, or HB LEDs. These tiny lights appear in digital clocks, televisions and streetlights.
LEDs are completely different from the light bulbs. Most of those glass bulbs belong to a type called incandescent lights. Inside, electricity heats a metal coil to about 2,200 degrees Celsius. At that temperature, bulbs give off light we can see. Ninety percent of energy produced by incandescent lights, however, is heat and invisible. With all that wasted energy, bulbs burn out quickly. They are also easily broken.
LEDs, on the other hand, are like tiny pieces of rock made up of molecules that are arranged in a crystal structure. When an electric current passes through an LED, the crystal structure produces light. Unlike incandescent bulbs, they can produce light of various colors. Within an LED, the type of molecules and
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their particular arrangement determines what color is produced.
The Huichol don't use electricity because ______. 【单选题】
A.it is too difficult for them to change their lifestyle
B.they know nothing about it
C.it costs too much to string power lines
D.they don't need it
正确答案:C
答案解析:本题有一定难度，关键在吃透句意，答案依据比较明显，带着题干信息词回文章定位，答案依据主要在文章第一段第二句：That's because it's too expensive to string power lines to the remote mountain areas where they live．谈到将电力设施铺设到山里投资巨大，string是引申意义，此处是“铺设”的意思，回来看选项，C项和原文句意相符，答案是C。
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