The bulk fraction is a mixture of methane, carbon dioxide, hydrogen, nitrogen and oxygen. These are measured in terms of percentage by volume.

主要成分是甲烷，二氧化碳，氢气，氮气和氧气的混合气体，这些成分的含量一般用所占填埋气的体积比来表示。

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Based on the mixture theory, a mathematical model for the sedimentation of soils in the steady water is established, depending on the volume fraction of the soils.

从混合物理论出发，建立了以土体颗粒体积含量为控制变量的土体静水沉降方程。

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It was shown that while the upper limit of volume fraction was about 20%, particle mixture might be significantly separated in a vibrated fluidized bed.

研究表明：当入选体积量的分选上限为20%时，流化床才能对颗粒混合物进行有效的分选，并且在振动条件下比在非振动条件下的分选效率略高一些。

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