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a lamp【问】 The gas-filled tungsten filament lamp is more of a furnace than a lamp. Since it uses ninety per cent of the power to produce unwanted heat and uses only ten percent to makelight.[原译]这种充气钨丝灯与其说是一盏灯,不如说是一个火炉。因为它耗去90%的电能去 ...... （共840字） [阅读本文]>>
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