With the help of group theory and number theory , analyzing the character of the defining relations of p- groups (where p is an odd prime ) and the properties of automorhism and other properties such as the properties of metabelian,regularity,p-commutativity and some properties of equivalence,by solving equations of congruence .

pH and the exchangeable aluminum content in acid soils as affected by parent materials and cropping systems;

This paper deals with the effect of organic matter and CaCO_3 on exchangeable aluminum in red soils developed fromparent material of granite and Quaternary red clay.

Profile distribution of exchangeable calcium and magnesium in an aquic brown soil as affected by land use type.;

The contents of exchangeable calcium and magnesium in Hunan tobacco-growing soils and their effects on tobacco quality;

Discussions on the determination methods of exchangeable calcium,magnesium and potassium in south acid soil;