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31. There are many kinds of forms of gas discharge, but the main form is soft coal seam gas discharge.

32. The coal transmutative degree and variational rule of coal seam physical character are different in the prospection for CBM. The situation restricted CBM industrialization in China.

33. The occurrence of rock burst not only need a great deal of elastic energy gathering in the coal seam and the around rock stratum, but also the external energy released by the main key stratum break.

34. The research indicates that volume modulus, cohesion and internal friction angle of coal seam around the roadway have a great influence on stress distribution.

35. Using joint inversion of logging and seismic data, the transverse change of coal measure was studied and the lithologies of coal seam roof and bottom was predicted.

36. This paper goes further into blast - winning technology of the composite coal seam face.

37. The storage, application and forecast of coal seam gas in Hegang mine field are introduced, and the detailed mining area and way for earlier and later stage are provided.

38. The distribution patterns of underground coal seam is diversified. The plane distribution is only one of the simple curved surface distribution patterns.

39. The II3123 face is a light type caving face of three-soft coal seam. the roof is cracked, sloughing and roof fall often occur.

40. Optimizing the Construction Organization Planning, Decreasing the Tunes of Uncovering Coal Seam, Shortening the Period of Mine Construction.

41. Coal Mine and the coal seam 13 - 1 has especially complex hydrogeology condition.

42. The Gaussian curvature of No.3 coal seam in Qinshui basin is calculated.

43. The surrounding rock of roadways in soft coal seam has low strength and bad stability.

44. The mechanism and control of coal seam with soft coal,[www.Sentencedict.com] roof and floor roadway floor heave is a difficult problem in mining subject.

45. Factors affected coal seam permeability change and its law is analyzed.

46. This paper is a guide to precise determination of the content of coal seam methane.

47. Based on consideration of stress sensitivity of coal seam permeability, the single-phase flow rule of coal-bed gas in coal and cleats is studied by using non-equilibrium adsorption model.

48. Drilling borehole in hard coal seam is mostly used to discharge gas, and cross layer borehole, roof rock borehole and laneway are mainly used to discharge gas in soft coal seam.

49. Gas concentrations drop, and the effective gas drainage period of holes is shortened, because pores and cracks in the coal seam become completely developed after gas drainage.

50. Based on the difference between hard coal and deformed soft coal on physical characteristics, analyzing the response that deformed soft coal seam is on well log.

51. Geological condition in Zhaogezhuang coalmine, Kailuan is very complex. Numerous minor scaled structures and coal seam occurrence are main limitation factors to mine development all along.

52. Coal body is watered by deep hole high pressure above mid-hard coal seam to soften the harder coal so as to improve the working efficience. It's a new way for mechanization mining in harder seam.

53. This study provides a scientific method about studying the gas content of the coal seam unmined and provides the basic data about the safe mining.

54. There are of forms of gas discharge , but the form is soft coal seam gas discharge.

55. Making use of horizontal pinnate branch well to develop and utilize coal seam gas, is a new drilling technique, which is different from horizontal drilling and has its own uniqueness.

56. The crack in the coal seam is divided into two kinds: endogenic crack and exogenous crack.

57. Essential way of solving the gas drainage problem of low permeability coal seam is seam permeability.

58. It was discovered that the gallium is more than marginal grade in content and enriched in lower coal seam and floor, and occurs mainly in diaspore.

59. Based on 172 borehole data of northern Shenmu coal mine, the paper is directed at to anglicizing the floor elevation trend of 5-2 coal seam by using the trend analysis method.