Analyzed coal-bed gas hosting features in Zhongling mine through coalfield geological exploration data,summarized practice and application of both walls of roadway drainage technique,affirmed this technique as effective outburst eliminating measure during anthracite roadway advancing.

This paper carries on the error analysis to the present crankshaft phase angle measuring technique,and proposed one kind of measuring error elimination measure.

Research on cold bending and re bending crack of remained heat treated reinforced bar and the elimination measures;

This article researches mailnly about the influence of gear,the gear part′s external structure making up with 20 CrMnTi and milling crack in heating treatments of rotation cuts′gears,also gives the elimination measures.