The combustion sources in our country are coal combustion, oil burned vehicles, living fuels and so on.

我国燃烧源主要是煤燃烧、燃油机动车和农村生活燃料等。

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Persistently elevated levels of fine particle pollution are common across many urban areas. Fine particle pollution often originates from combustion sources such as power plants and motor vehicles.

在许多城市区域，常常出现细小颗粒污染程度呈持续性增高情况。细小颗粒污染通常来自发电厂和机动车等燃烧源。

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The major sources of anthropogenic emissions of NO2 are combustion processes (heating, power generation, and engines in vehicles and ships).

人为释放二氧化氮的主要来源是燃烧过程(供热、发电以及机动车和船舶的发动机)。

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The report says government efforts to control emissions of reactive nitrogen from combustion sources have been more successful.

BBC: Nitrogen pollution 'costs EU up to ?280bn a year'

First, when released into the air as a result of incomplete combustion (from sources as varied as badly serviced diesel engines and forest fires), soot particles absorb sunlight, and so warm up the atmosphere.

FORBES: Soot and CO2 In The Arctic