2. 职称考试
  3. 下面有3 篇短文，每篇短文后有5 道题。请根据短文内容，为每题确定1 个最佳选项。 Weaving with Light In the S...

下面有3 篇短文，每篇短文后有5 道题。请根据短文内容，为每题确定1 个最佳选项。 Weaving with Light In the S...

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问题 下面有3 篇短文，每篇短文后有5 道题。请根据短文内容，为每题确定1 个最佳选项。
   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. Thafs because ifs 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 named the fabrics “ Portable （轻便的） Lights” . Portable Lights have the potential to transform the lives of people without electricity around the world.
At the core of Portable Lights technology are devices called high-brightness lightemitting diodes （高亮度发光二极管）, or HB LEDs. These tiny lights appear in digital clocks, televisions, andstreetlights.
LEDs are completely different from the light bulbs （灯泡）. Most of those glass bulbs belong to a type called incandescent lights （白炽灯）. Inside, electricity heats a metal coil （线圈） 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 （分子） that are arranged in a crystal structure. When an electric current passes through a LED, the crystal structure produces light. Unlike incandescent bulbs, they can produce light of various
colors. Within a LED, the type of molecules and their particular arrangement determine what color is produced.
The central part of the Portable Lights technology is
选项 A glass bulbs.
B HB LEDs.
C digital clocks.
D incandescent lights.
答案B
解析文章第四段第一句话提到：At the core ofPortable Lights technology are devices called high-brightness light-emittingdiodes, orHB LEDs. 可知这种移动灯的核心技术是高亮度发光二极管，或简称HBLEDs。答案为B。
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