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LED Lighting 1 An accidental discovery announced recently has taken LED lighting to a new level, suggesting it could soon offer a cheaper, longer-lasting alternative to the traditional light bulb. The breakthrough adds to a growing trend that is likely to eventually make Thomas Edison&39;s bright invention obsolete. LEDs are already used in traffic lights, flashlights, and architectural lighting. They are flexible and operate less expensively than traditional lighting. 2 Michael Bowers, a graduate student2 at Vanderbilt University, was just trying to make really small quantum dots, which are crystals generally only a few nanometers big. Quantum dots contain anywhere from 100 to 1,000 electrons. They&39;re easily excited bundles of energy, and the smaller they are, the more excited they get. Each dot in Bowers&39; particular batch was exceptionally small, containing only 33 or 34 pairs of atoms. 3 When you shine a light on quantum dots or apply electricity to them, they react by producing their own light, normally a bright, vibrant color. But when Bowers shined a laser on his batch of dots, something unexpected happened. He was surprised when a white glow covered the table. The quantum dots were supposed to emit blue light, but instead they were giving off a beautiful white glow. 4 Then Bowers and another student got the idea to stir the dots into polyurethane and coat a blue LED light bulb with the mix. The lumpy bulb wasn&39;t pretty, but it produced white light similar to a regular light bulb. 5 LEDs produce twice as much light as a regular 60 watt bulb and burn for over 50,000 hours. The Department of Energy estimates LED lighting could reduce U. S. energy consumption for lighting by 29 percent by 2025. LEDs don&39;t emit heat, so they&39;re also more energy efficient. And they&39;re much harder to break. 6 Quantum dot mixtures could be painted on just about anything and electrically excited to produce a rainbow of colors, including white. The main light source of the future will almost surely not be a bulb. It might be a table, a wall, or even a fork. Paragraph 1 ______ A LED Lighting Is Not MatureB LED Lighting Will Replace Traditional LightingC Almost Everything Could Be the Main Light Source in the FutureD LED Lighting Has Many AdvantagesE Bowers Made an Unexpected DiscoveryF LED Light Bulbs Look Lumpy Paragraph 3 ______ A LED Lighting Is Not MatureB LED Lighting Will Replace Traditional LightingC Almost Everything Could Be the Main Light Source in the FutureD LED Lighting Has Many AdvantagesE Bowers Made an Unexpected DiscoveryF LED Light Bulbs Look Lumpy Paragraph 5 ______ A LED Lighting Is Not MatureB LED Lighting Will Replace Traditional LightingC Almost Everything Could Be the Main Light Source in the FutureD LED Lighting Has Many AdvantagesE Bowers Made an Unexpected DiscoveryF LED Light Bulbs Look Lumpy Paragraph 6 ______ A LED Lighting Is Not MatureB LED Lighting Will Replace Traditional LightingC Almost Everything Could Be the Main Light Source in the FutureD LED Lighting Has Many AdvantagesE Bowers Made an Unexpected DiscoveryF LED Light Bulbs Look Lumpy Unlike traditional lighting, LEDs do not give out heat so ______. A traditional lighting is less durable and dearerB a laser excited the quantum dotsC America adopted LEDsD graduate students work hardE quantum dot mixtures are magicF it is more efficient Edison&39;s bright invention is likely to be outdated because ______. A traditional lighting is less durable and dearerB a laser excited the quantum dotsC America adopted LEDsD graduate students work hardE quantum dot mixtures are magicF it is more efficient Something unexpected happened during Bower&39;s experiment when ______. A traditional lighting is less durable and dearerB a laser excited the quantum dotsC America adopted LEDsD graduate students work hardE quantum dot mixtures are magicF it is more efficient Over one quarter of energy consumption for lighting could be saved by 2025 if ______. A traditional lighting is less durable and dearerB a laser excited the quantum dotsC America adopted LEDsD graduate students work hardE quantum dot mixtures are magicF it is more efficient
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A.
用吸奶器吸乳
B.
生麦芽煎汤喝
C.
少喝汤水
D.
让新生儿多吸吮
E.
皮硝敷乳房
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A.
应扣押U盘并制作笔录
B.
检查U盘内的电子数据时,应将U盘拆分过程进行录像
C.
公安机关移送审查起诉时,对U盘内提取的木马程序,应附有该木马程序如何盗取账号密码的说明
D.
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A.
一年以上
B.
一年以下
C.
两年以上
D.
五年以内
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A.
3
B.
6
C.
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D.
12
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A.
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B.
ADSL调制解调器
C.
无线路由器
D.
同轴电缆
【简答题】STF 、STR端子信号同时为ON时,变频器会_________。
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A.
用吸奶器吸乳
B.
生麦芽煎汤喝
C.
少喝汤水
D.
让新生儿多吸吮
E.
芒硝敷乳房
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A.
无线网卡
B.
ASDL调制解调器
C.
无线路由器
D.
同轴电缆
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