It is a new subject to explore and look for the methods and indexes to describe and depict the evolutional characteristics of seismic precursor complex picture.

探索、寻找描述、刻画地震前兆复杂图像演化特征的方法与指标，是地震预报研究的新课题。

youdao

The vibrational frequencies and vibrational modes of reactants, precursor complexes, transition state, successor complex and product were analyzed.

分析了反应物，前驱配合物，过渡态，后继配合物和产物的振动频率及振动模式。

youdao

Fibrous cobalt complex, a precursor of fibrous cobalt powders, can be prepared by coordination precipitation, using ammonia, oxalate and cobalt chloride as the raw materials.

以氨水、草酸和氯化钴为原料，通过配位沉淀制备得到了纤维钴粉前驱体———纤维状复杂钴盐粉末。

youdao

One key element in searching for life on Mars is the presence of methane in the Martian atmosphere As a simple carbon compound, methane is often a precursor to the formation of the complex organic chemicals that make life possible.

FORBES: Curiosity Sniffs The Martian Atmosphere But Finds No Sign Of Life