The pre-industrial carbon dioxide amount was 280 parts per million (ppm). Humans, by burning coal, oil and gas, have increased this to 385 ppm; it continues to grow by about 2 ppm per year.

在前工业时代，二氧化碳含量为280ppm，人类燃烧煤炭和油气的行为使其上升到385ppm，而这一数值还在以每年2ppm的速率增长。

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Use of gas and air pre-mixed and then burning to intense burning was carried out and the full and absolute absence of any explosion hazard.

使用时燃气预先与空气充分混合，再进行燃烧，使燃烧进行得剧烈而充分，绝对无任何爆炸危险。

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Heat is also extracted from the flue of a log burning stove to pre-heat hot water.

从烟道中提取的热量还可以用于预热水炉。

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