Results 21 to 30 of about 41,310 (228)
Gong-kuang zidonghua, 2022 In order to solve the problem of difficult prevention and control of coal and gas outburst in thin coal seam, the distribution characteristics of effective extraction area in thin coal seam are analyzed. Due to the limitation of the thickness of the thin
ZHANG Nan, XU Jiuzhou, QIU Liming
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Research on the prediction of liquid CO2 phase transition cracking radius in coal seams
Gong-kuang zidonghua, 2023 Predicting cracking radius is a prerequisite for determining the holes spacing of gas extraction technology by liquid CO2 phase transition cracking and permeability improvement, which directly affects the gas extraction effect.
WANG Changlu +4 more
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Morphological characteristics and permeability evolution of deep mine gas drainage boreholes
Frontiers in Earth Science, 2022 Structural coal has low permeability and high gas content. The increase of mining depth seriously restricts the safe mining of deep mines. Hydraulic flushing is the main means of gas extraction.
Xiao Liu +5 more
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Research on determination method of effective drainage radius of gas drainage borehole
Gong-kuang zidonghua, 2020 In order to solve the problems of complex process and lower accuracy in current determination method of effective drainage radius of gas drainage borehole, a determination method of effective drainage radius was put forward, which is based on the law of ...
LIU Dianping, MA Wenwei
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Meitan xuebao, 2023 The instability and collapse of drainage boreholes is one of the key problems that hinder the efficient extraction of coal-bed methane (CBM). In order to solve the problem of instability and collapse of extraction boreholes in soft coal seams, based on ...
Xuebo ZHANG +4 more
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Meikuang Anquan, 2023 At present, in drilling design and evaluation, the shape of hydraulic flushing hole is usually equivalent to cylinder, which is one of the important bases to determine the effective extraction radius.
LIU Xiao, JING Tianxiang, XUAN Dequan, HU Shixiong, LI Yong1, XU Sen
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Advances in Civil Engineering, 2021 Gas disasters have been always a major hidden danger that affects mining safety in coal mines. Gas drainage by drilling is the fundamental method of gas control in coal mines.
Zongyong Wei +5 more
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The Synergistic Effect in Solvent Extraction—The Correlation of the Ionic Radius of Rare Earth Elements with the Stability Constants of Rare Earth Benzoyltrifluoroacetonate Adducts with n-Hexyl Alcohol, TBP and TOPO [PDF]
Bulletin of the Chemical Society of Japan, 1967 Abstract The synergistic effects of n-hexyl alcohol, TBP and TOPO on the extraction of rare earth ions with benzoyltrifluoroacetone in benzene have been studied. The stability constants of the adducts were determined by means of the curve-fitting method.
Tsunenobu Shigematsu +3 more
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Energy Science & Engineering, 2023 Aiming at the application of hydraulic punching technology in soft, low permeability, and high gas coal seams in Changping Coal Mine, there are problems such as large workload, poor permeability enhancement effect, and the formation of “blank zones” in ...
Rui Min +4 more
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Physical optimal design and analysis of 99Mo production in new type molten salt fast reactor
He jishu, 2022 Background99Mo has important applications in nuclear medicine field. It can be produced in a 235U fission reactor with high yield and specific activity.PurposeThis study aims to optimize the core parameters of new type molten salt fast reactor, and then ...
LIU Xiaolin +5 more
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