isotopic fractionation

This change does not disturb isotopic fractionation andthethe stalagmite able to keep environment information.

转化作用不影响同位素分馏,石笋同时全面记录古气候环境信息.

The catalysis of enzymes causes much more complexity for the isotopic fractionation under microbial actions.

辅酶对反应的催化作用使微生物作用造成的同位素分馏更加复杂.

In the following primary migration simulation deuterated normal C_ ( 15)( n-C_ ( 15) D_ ( 32)) was added into different source rocks to study the isotopic fractionation in primary migration.

下面的初次运移模拟实验通过在源岩中加入氘代的正构十五烷（n-C15D32）来研究初次运移中的同位素分馏。

The sample pretreatment method can meet the requirement of boron isotopic determination by thermal ionization mass spectrometry without any isotopic fractionation of boron. The precision for boron isotopic determination is better than 0.05% RSD.

采用该方法从岩石样品中提取、分离出来的硼能满足硼同位素质谱法测定的需要，不产生硼同位素分馏，硼同位素测定精度大多优于0.05%。