And so, when you think about how much cement concrete are consumed annually on the planet, this becomes a considerable point source of greenhouse gas emissions.

当你想到,在地球上每年要消耗多少的水泥混凝土的时候,这将是温室气体排放的,一个主要来源。

麻省理工公开课 - 固态化学导论课程节选

is actually looking at how to regulate greenhouse gases under existing environmental laws,

其职务是研究在现行的环境法下如何管理温室气体的排放，

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And as you know, carbon dioxide is implicated as a greenhouse gas.

你知道的，二氧化碳意味着温室气体。

麻省理工公开课 - 固态化学导论课程节选