the word"yan"appearred one hunderd and seventeen times in the book of"Warring States",in this passage,we will summarize the usage and parts of speech about the word"yan"and inspect the word form four aspects of instructions pronouns,doubt pronouns,modal particles and the auxiliary speech.

Cause of low water-cut oil layer in Yanqi Basin and the interpretation method;

Evaluation of Reservoir Heterogeneity by Flow Unit Index-an example from Baobei block of Baolang oilfield，Yanqi basin;

Characteristics and pool forming pattern of oil and gas reservoirs in Yanqi bas in.;

Thro ugh quantitative statistics of petroleum micro-constituents from wells by sampl e analysis and study of various coal-measure facies parameters in Yanqi basin ,it is found that they are high in gelation.

Processing Technique of Pre-stack Migration in Complex Structures of Yanqi Basin;

Research on organic microscopic component analysis and hydrocarbon generation mechanism of coal measure source rock in Yanqi Basin;

Inorganic geochemical features of oilfield water in Yanqi basin and its connection with hydrocarbon preservation;