Teachers should give children abound sports materials and chances.

The multiple function additive of SP-1 for cement slurry was prepared from such active materials as micro silica, swelling pearlite and diatomite and activator of CK21 by synthesization and the effects of reaction temperature and monomer concentration on properties of SP-1 slurry were studied.

This article narrates the requirements of the performance of piston material as well as a preparation plan on carbon fiber aluminum-based compound materials for piston, and discusses the potential questions and specific steps in the testing process, thus provides a new approach to the preparation for piston material.

The article comprehensively and systematically introduces the development situation of piston materials for internal combustion and points out that from the long-term development strategy,low-cost and high-performance compound materials will be the major ones.

The advances in research on modified activated carbon materials in surface structure and physico-chemical properties are reviewed.

This text summarizes the research situation of FGD by the activated carbon materials (concentration on studying at present: oxygen functional groups; nitrogen functional groups;metal and metal compound on the surface of activated carbon materials).

By adding pore forming agents,which evaporate during carbonization and leave behind pores in the carbon matrix, into the parent polymer ,pore size distribution in activated carbon can be controlled.