Reasons of Cl~- contamination in karst ground water of Jiaozuo Coal Mining Area;

The Anti-imperialism Strike in Jiaozuo Coal Mines of the Peking Syndicare.Ltd in 1925——In memory of the 80th anniversary of the strike and the establishment of the labour union in Jiaozuo coal mines;

The anti-imperialism strike in Jiaozuo coal mines taking place in 1925 hit the aggressive force of British and American imperialism in China heavily, and raised the class consciousness and the fighting level of the workers of Jiaozuo coal mines.

The paper deals with the ever-lasting spirit of particularly good fighters of the worker of Jiaozuo coal mines in the Democratic Revolution Period, the Socialist Construction Period and the Reform Period.

Under the role of the Pacific Plate and the North China plate collision together, the structure of Jiaozuo mining area is controlled by the Taihang uplift, Piedmont fracture; Jiaozuo coal is mainly affected by the control of Taihang piedmont fault zone, thereby is developped into fault block structure, the border of which is fault-controlled ladder, the base, graben.

Analyed the mining conditions of Jiaozuo area,through the investigation of Ⅱ1 coal seam roadway layout in Jiaozuo Coal Industrial Group,and aimming at the merits and faults and application of existing roadway layout,this paper summarized the roof and soleplate arrangement which is suitable for Jiaozuo mining area condition.

Determination of evoked potential in coke oven workers