In order to study the dynamic action and physical effects of coal seams and gas,a simulation system for this dynamic action was developed and a physical model built in our laboratory.Using this newly built model,the v...In order to study the dynamic action and physical effects of coal seams and gas,a simulation system for this dynamic action was developed and a physical model built in our laboratory.Using this newly built model,the volume of coal outbursts and the temperature during the outburst process were studied.The results show that:1) for coal seams with similar structure and components,two factors,i.e.,gas pressure and ground stress affect the volume of coal outbursts,with gas pressure being the more important of the two and 2) the changes in coal temperature,both its increase and decrease,are affected by ground stress and gas pressure,it is a process of change.Preliminary tests show that the system can simulate the dynamic interaction of coal and gas,which is helpful for studying the dynamic mechanism of solid-gas coupling of gas and coal.展开更多
We have collected 18 samples corresponding to 18 locations in the middle and lower reaches of the Huaihe River. The sediment samples were tested for their pH level,percentage of solids,organic matter and five heavy me...We have collected 18 samples corresponding to 18 locations in the middle and lower reaches of the Huaihe River. The sediment samples were tested for their pH level,percentage of solids,organic matter and five heavy metals (Cr,Cu,Zn,Cd and Pb). The average concentrations of Cr,Cu,Zn,Cd and Pb of the 18 sampling locations were re-spectively 56.1,22.2,70.0,0.17 and 20.4 μg/g. Compared with their background values,the average concentrations of Zn and Cu in sediment samples from the Huaihe River were slightly higher,while the average concentrations of Cr and Pb were slightly lower. The concentration of Cd in all sediment samples was higher than its background value,while the average concentration of Cd in all sediment samples was about twice the amount of the background value. The concen-tration of the five heavy metals was lower than that of the Yangtze River. A correlation analysis revealed that heavy metals have similar geochemical feautures. The geo-accumulation index (Igeo) was used to evaluate the degree of pollu-tion of the Huaihe River sediments. The index reveals that the sediment samples are largely ranked from zero pollution to no to medium pollution.展开更多
文摘In order to study the dynamic action and physical effects of coal seams and gas,a simulation system for this dynamic action was developed and a physical model built in our laboratory.Using this newly built model,the volume of coal outbursts and the temperature during the outburst process were studied.The results show that:1) for coal seams with similar structure and components,two factors,i.e.,gas pressure and ground stress affect the volume of coal outbursts,with gas pressure being the more important of the two and 2) the changes in coal temperature,both its increase and decrease,are affected by ground stress and gas pressure,it is a process of change.Preliminary tests show that the system can simulate the dynamic interaction of coal and gas,which is helpful for studying the dynamic mechanism of solid-gas coupling of gas and coal.
文摘We have collected 18 samples corresponding to 18 locations in the middle and lower reaches of the Huaihe River. The sediment samples were tested for their pH level,percentage of solids,organic matter and five heavy metals (Cr,Cu,Zn,Cd and Pb). The average concentrations of Cr,Cu,Zn,Cd and Pb of the 18 sampling locations were re-spectively 56.1,22.2,70.0,0.17 and 20.4 μg/g. Compared with their background values,the average concentrations of Zn and Cu in sediment samples from the Huaihe River were slightly higher,while the average concentrations of Cr and Pb were slightly lower. The concentration of Cd in all sediment samples was higher than its background value,while the average concentration of Cd in all sediment samples was about twice the amount of the background value. The concen-tration of the five heavy metals was lower than that of the Yangtze River. A correlation analysis revealed that heavy metals have similar geochemical feautures. The geo-accumulation index (Igeo) was used to evaluate the degree of pollu-tion of the Huaihe River sediments. The index reveals that the sediment samples are largely ranked from zero pollution to no to medium pollution.
基金Supported by the National Natural Science Foundation of China （41172138） the Special Fund Project of Jiangxi Energy Bureau （20100730） Acknowledgments The authors wish to thank Professor Tang Xiuyi from Anhui University of Science and Technology for his constructive advice. The authors also express their gratitude to the technical personnel from Jiangxi Exploration Institute of Coalfield Geology, Jiangxi Coal Group Corporation, for their kind help.
