Experimental study on thermal dilation coefficient (TDC) of cement paste at early-age;

Research on retarding mechanism of calcium lignosulfonate to cement paste;

A method to evaluate rheological behavior of cement paste with high fluidity and low water-cement ratio;

Study on optimazing measure of neat cement slurry and cement paste for oil well;

A mud purification and recovery device used for non-open-cut directional drilling;

It is pointed out that the column of whirlpool gaseity in the center has a marked effect on mud purification.

5dB at 16GHz;on the average,hydrated cement with fly ash,has absorption of 6～10dB in 1～4GHz frequency range,but 4～6dB in 4～18GHz while at 17GHz,with 30% fly ash at thickness of 30mm,has absorption of 8.

This article analyses the typical disposing method of waste drilling mud in foundationengineering,and narrates the tentative idea of GNJ-2A mud purifier,Shale shaker and cycloneare used to compose a three-step concentrative purification circulation system on GNJ-2Amud purifier,and direct circulalion and reverse circulation mud purification lechnological pro-cess are properly designed.

shale shaker and cyclone are used used to compose a three-step concentrative purification sys-tem on GNJ-2A mud purifier,direct circulation and reverse circulation mud purification technological process are properly designed.