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Li G.-B.,China University of Mining and Technology | Li G.-B.,Huozhou Mining and Electricity Group | Li G.-F.,University of Chinese Academy of Sciences | Li G.-F.,Jincheng Anthracite Mining Group
Meitan Xuebao/Journal of the China Coal Society

In order to find out the feasible co-layer drainage between No. 3 and No. 15 coal reservoir in the southern Qinshui Basin, according to the producing gas characteristics of CBM vertical wells, the factors of the height of the critical production gas, the grades of reservoir pressure, the ability of supply for liquid and the permeability are the main controlling factors to influence the joint drainage, and the suitable conditions about the joint drainage was gained. According to the the exploration data in Sihe block, the main controlling factors were analyzed. The results show that various controlling factors are suitable in Sihe block. The drainage experiment validates that the theory is reliable. Source

Feng G.-M.,China University of Mining and Technology | Wang C.-Z.,Jincheng Anthracite Mining Group | Li F.-K.,China University of Mining and Technology | Li F.-K.,Jizhong Energy Group Co. | Jia K.-J.,China University of Mining and Technology
Caikuang yu Anquan Gongcheng Xuebao/Journal of Mining and Safety Engineering

To liberate the unexploited coal resources beneath buildings, a new kind of super-high-water material can be used as the filling material in goaf, whose water volume and water cement ratio can be reached to 97% and 11:1, respectively. Based on the basic properties of super-high-water materials, bag-type filling mining method is proposed. In this technology, the mixed slurry of super-high-water materials are injected into the filling bags which have been erected in goaf in advance, and then the solidified filling bodies can slow down the surface subsidence effectively by controlling overlying strata activity. The technology has been applied successfully in the experimental filling face in Taoyi Coal Mine. The application shows that the super-high-water material is a kind of goaf filling material with good performance in a wet, cold and closed underground environment, and the technology is an advanced green mining method to liberate unexploited coal seams under buildings, with the obvious advantages of simple filling process, low initial investment, high mechanization degree, convenient practical operation, strong adaptability to the geological conditions and mining technologies in coal mines, and so on. Source

Sun Q.-X.,China Coal Research Institute | Mou Y.,China Coal Research Institute | Yang X.-L.,Jincheng Anthracite Mining Group
Meitan Xuebao/Journal of the China Coal Society

For the purpose of exploring"two-zone" height of soft overlying strata working face, taking Shenhua Ningxia Coal Industry Group Hongliu Coal Mine 1121woking face as an example, three kind of technological method to explore "two-zone" height were used. Three method were loses of drilling fluid measuring, borehole wall observing by colour TV and transient electromagnetic method(TEM) geophysical exploration. On condition that the coal mining technology is fully-mechanized and fully-seam caving mining and the seam is slightly-tilt, thick and the overlying strata is soft, comprehensive research show that the caving height is 8.55 times the thickness of the coal seam, and the height of permeable fracture zone is 12.51 times the thickness of the coal seam. Three techniques have great difference in accuracy though they are the direct observation. Authors conclude that borehole colour TV is the best, loses of drilling fluid measuring is next, TEM geophysical exploration is the worst. Source

Lijun B.,China University of Mining and Technology | Lijun B.,Jincheng Anthracite Mining Group | Wang Z.,China University of Mining and Technology | Hao W.,China University of Mining and Technology | And 2 more authors.
Proceedings of the 2015 27th Chinese Control and Decision Conference, CCDC 2015

The beam pump unit is widely used in Coal-bed methane(CBM) wells for mining of CBM. In the past few years, the main electrical drive system applied in beam pump unit for CBM wells is electromagnetic speed motor. Aiming at drawbacks existed in electromagnetic speed system such as high energy consumption and low system efficiency, we propose a variable frequency speed system based on vector control technology for CBM wells. This paper analyzes and builds the mathematical model of the load torque of the beam pump and the mathematical model of AC drives control system of the beam pump using vector control technology. Based on the above analysis, we further set up the whole simulation model of the vector control system of beam pump for CBM wells. The simulation results show that the control system can automatically adjust the real-time dynamic torque motor current, in order to match the output torque of the motor with the load characteristics of the beam pump, and prove to having an excellent performance of speed control. The field experiment data verify that compared with the electromagnetic speed system, the proposed control method using in CBM wells can definitely improve the system efficiency and reduce the energy consumption. © 2015 IEEE. Source

Junmei L.,Jincheng Anthracite Mining Group
Cancer Research and Clinic

Objective: To explore the expressions of Topo-II, GST-π in gastric cancer tissues and normal gastric mucosa tissues, to reveal its relationship with clinical pathological features and significance. Methods: Immunohistochemical method was used to detect Topo-II, GST-π expressions in 100 cases of gastric carcinoma and 20 cases of normal gastric mucosa, make a comprehensive analysis combined with clinical pathology data. Results: There were significant difference of expression of Topo-II, GST-π between the normal gastric mucosa tissues and gastric cancer of different degree of differentiation. Topo-II positive expression rate of 5.0 % (1/20), 100 % (30/30), 96.7 % (29/30) and 87.5 % (35/40) respectively; GST-π positive expression rate were 60.0-% (12/20), 83.3%(24/30), 96.7 % (29/30) and 100.0 % (40/40) respectively (P < 0.05). The expressions of Topo-II, GST-π in gastric cancer tissue were not relevant to patient' s sex, age, tumor location, infiltration depth (P > 0.05). Topo-II associated with the differentiation degree and lymph node metastasis of tumors, with the decreasing degree of tumor differentiation, lymph node metastasis, Topo-II expression also decreased. GST-π was associated with tumor diameter, degree of differentiation and lymph node metastasis, the lower the degree of differentiation, lymph node metastasis, tumor diameter the more, GST-π expression increased (P < 0.05). GST-π and Topo-II were negative correlation and both expressed in gastric cancer tissue (P < 0.01). Conclusions: The expressions of Topo-II in gastric cancer tissue is associated with the differentiation degree and lymph node metastasis of the tumor. GST-π is associated with tumor diameter, the degree of differentiation and lymph node metastasis. GST-π and Topo-II in gastric cancer tissues are negatively correlated. Source

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