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Study on evolution law of coal permeability characteristics under long-term stress [PDF]
In the process of gas extraction, deep coal is affected by high ground stress for a long time. In order to explore the permeability characteristics and evolution law of coal under long-term stress.
Zhenping SUN
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Shuitu Baochi Xuebao, 2017 以重金属Cd为单一污染源的棕壤作为供试土壤，设定-10，-20，-30 ℃三个温度作为冻结温度，10 ℃作为融化温度进行土壤冻融循环试验。通过测定冻融作用后土壤团聚体粒径组成、土壤质量平均直径、团聚体粒径中Cd的质量负载率以及土壤团聚体中Cd的赋存形态，研究冻融作用对棕壤团聚体稳定性及Cd在不同团聚体粒径中分布与赋存形态的影响。结果表明：土壤经过冻融作用后，＞2 mm的团聚体比例显著增加(P＜0.05)，增加范围为38.4%～54.6%，土壤质量平均直径显著增加(P＜0.05)。经过冻融作用后 ...
王梦露 +7 more
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Guangtongxin yanjiu, 2013 对由FBG（布拉格光纤光栅）和LPFG（长周期光纤光栅）构成的SFG（超结构光纤光栅）,采用耦合模方程的相似变换解法,研究了应变梯度和温度梯度对SFG的透射谱和反射谱的影响。模拟结果表明,SFG在应变梯度或温度梯度的作用下,其反射光谱和ν阶包层模的透射光谱按确定规则独立漂移,据此可以同时求出光栅所在位置的应变和应变梯度,或温度和温度梯度。
王永皎, 米浩坤, 梁磊
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Gaoya dianqi, 2010 机械式SF6密度控制器在运行中时有误报警现象。对国内外已使用过的4类SF6密度控制器的不同结构、SF6温度、环温以及使用处海拔高度对监控特性的影响进行了分析。得出,Ⅳ型国产密度控制器质量稳定、监控精度较好;目前使用的SF6密度控制器对GCB/GIS的SF6密度具有一定的监控作用,但不能避免开关运行时出现的SF6密度示数"假高"现象,为消除密度示数"假高"、对环境温度的欠补偿和海拔影响,根本出路是开发新型智能化的SF6密度控制器。
黎斌
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Spontaneous combustion characteristics of hydrothermal eroded coal in deep mining [PDF]
In the process of deep mining, the temperature of mine water is significantly higher than that of shallow coal seams. The erosion of high-temperature hydrothermal fluids affects the physical and chemical characteristics of coal, which in turn affects its
Daimin HU +5 more
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Stress assessment and control measures for deformed tunnel-crossing pipeline section [PDF]
Objective It is common for long-distance oil and gas pipelines to traverse mountain tunnels. The sections of pipelines passing through tunnels are susceptible to significant deformation due to internal pressure and temperature effects during the ...
Chunbin QIU
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Geological conditions of coal reservoir occurrence in the Southern Qinshui Basin and its impact on permeability [PDF]
The occurrence and output of coalbed methane (CBM) are controlled by the occurrence geological conditions of coal reservoirs, such as stress, pressure, and temperature.
Huaxin REN +5 more
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Dianci bileiqi, 1991 本文探讨金属氧化物无间隙避雷器耐受最严峻的工作负荷条件,探讨热崩溃条件的极限,研究采用避雷器的热模型,以预测热崩溃条件。根据电热模型的伏—安—温度曲线计算出功耗曲线,作为避雷器热性能研究的输入功率。根据每一时间阶段调节输入功率。根据试验,提出采用阀片最高允许温度作为任一避雷器运行极限,以避免热崩溃 ...
doaj
Research Status and Prospect of Flotation Separation of a Copper-lead Sulfide Ore [PDF]
The separation of copper and lead is one of the technical difficulties in complex sulfide ore beneficiation. On the basis of analyzing the general situation of copper-lead sulfide ore resources and the characteristics of mineral composition, this paper ...
Di YANG +3 more
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