NT_010
综合写作
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综合写作NT 010音频
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Compact fluorescent lamps (CFLs) are a relatively new type of lighting technology. In a CFL, electricity passing through mixture of gases causes phosphor coating to glow(phosphor is special light-emitting material). Since CFLs are more energy efficient than the standard light bulbs(also known as incandescent bulbs), some governments propose policies and even laws ensure that all users replace incandescent bulbs with CFLs. However, replacing incandescent bulbs with CFLs is ill-advised: CFLs areinferior to incandescent bulbs in several important respects.
First of all, CFLs are much more expensive than incandescent bulbs. A CFL may cost up to ten times as much as an equivalent incandescent bulb As incandescent bulbs are phased out, consumers and businesses will be required to purchase CFLs, which will be a financial burden.
Second, CFLs pose a danger to the environment. CFLs contain mercury, a toxic metal. Mercury is responsible for number of environmental problems; it can accumulate in oceans and waterways, for example, and poison fish, birds, and other wildlife. Although special recycling methods exist that should allow the CFLs to be processed without releasing the mercury, many people are not used to recycling the bulbs. This means that most CFLs will not be recycled properly, will release their mercury upon being discarded, and will contribute to a serious environmental problem.
Third, CFLs do not produce the same quality of light as incandescent bulbs. The light produced by incandescent bulbs contains a mix of different colors; the combination of different colors is what makes incandescent light pleasing to the eye. In contrast, most types of phosphor coatin used in CFLs produce light only in narrow color ranges. For that reason, many people do not consider the light from CFLs attractive.
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