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碎软煤层多层深孔钻进技术与装备 被引量:2
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作者 冯达晖 《煤矿安全》 CAS 北大核心 2018年第6期78-80,共3页
碎软厚煤层大采高工作面瓦斯治理时,采用多层钻孔才能覆盖整个采高,同时还须保证足够的钻孔深度,才能满足瓦斯抽采的需要。针对碎软煤层多层深孔施工对钻进装备的要求,研制了ZDY10000L大功率多层孔钻机,配套了宽翼片螺旋钻杆和优化了外... 碎软厚煤层大采高工作面瓦斯治理时,采用多层钻孔才能覆盖整个采高,同时还须保证足够的钻孔深度,才能满足瓦斯抽采的需要。针对碎软煤层多层深孔施工对钻进装备的要求,研制了ZDY10000L大功率多层孔钻机,配套了宽翼片螺旋钻杆和优化了外平钻杆加三棱钻杆的组合式钻杆及配套压风排站钻进工艺。在赵庄煤矿1308工作面现场试验表明:钻机组合变幅机构开孔高度范围可达1.5~3.0 m,满足多层钻孔施工需要;钻机的自动升降装置提高了多层孔施工效率和安全性;采用该套技术与装备施工的瓦斯抽采孔平均孔深大于100 m,成孔率大于85%。 展开更多
关键词 碎软煤 多层深 大功率钻机 组合变幅机构 升降机构 组合式钻杆
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轨道车辆转向架焊接构架多层深残余应力研究 被引量:3
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作者 胡文浩 李余江 孙林祥 《轨道交通材料》 2022年第1期24-28,共5页
为系统掌握多层深残余应力分布规律,综合采用X射线衍射法和超声波法,对焊接态、热处理态和喷丸态3种状态构架的焊缝表面及以下5.9 mm范围内多层深度的残余应力进行了综合测试研究。研究结果表明:焊接态构架呈现出“拉应力峰值-陡降-缓降... 为系统掌握多层深残余应力分布规律,综合采用X射线衍射法和超声波法,对焊接态、热处理态和喷丸态3种状态构架的焊缝表面及以下5.9 mm范围内多层深度的残余应力进行了综合测试研究。研究结果表明:焊接态构架呈现出“拉应力峰值-陡降-缓降-低值拉应力”的分段下降式分布规律;构架经热处理后,焊缝表面至以下0.85 mm共6种层深的残余应力均实现了均匀化分布;构架经喷丸处理后,表面至以下0.85 mm层深的残余压应力整体上呈“对勾状”分布,峰值出现在0.1 mm深度,0.85-1 mm深度后,拉应力缓慢下降,总体呈“不对称抛物线状”分布。提出了将研究成果在评价喷丸处理效果、辅助制定焊接及热处理工艺及评估焊接缺欠的影响等领域的应用启示。 展开更多
关键词 轨道车辆 转向架 焊接构架 残余应力 多层深
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多层支撑深基坑变形数值模拟正交试验设计研究 被引量:28
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作者 孙树林 吴绍明 裴洪军 《岩土力学》 EI CAS CSCD 北大核心 2005年第11期1771-1774,共4页
分析了多层支撑深基坑设计中的多个参数,对诸如挡墙和支撑的刚度指标等参数选取进行了分析。对深开挖进行了多因素多水平的有限元数值模拟,在此基础上进行了支撑刚度、位移柔度数、土体变性及强度参数等5因素的4水平正交试验设计,得出... 分析了多层支撑深基坑设计中的多个参数,对诸如挡墙和支撑的刚度指标等参数选取进行了分析。对深开挖进行了多因素多水平的有限元数值模拟,在此基础上进行了支撑刚度、位移柔度数、土体变性及强度参数等5因素的4水平正交试验设计,得出了深开挖中的各个参数对多层支撑深开挖变形的影响程度和各个参数的灵敏度。分析结果表明,墙体的位移柔度数是控制基坑开挖变形的主要参数,其他的参数诸如土体的弹性模量等对基坑变形的影响较小。 展开更多
关键词 多层支撑开挖 正交设计 位移柔度数 有限元模拟
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深立井揭穿多层突出煤层技术与实践 被引量:3
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作者 王厚良 王本忠 +3 位作者 王劲红 孙宝仁 魏金栋 张松 《煤炭科学技术》 CAS 北大核心 2009年第6期31-35,38,共6页
为了缩短了揭煤工期、加快成井速度,在淮北桃园煤矿扩建工程新副立井井筒、揭穿多层深水平突出煤层的施工中,采用突出煤层快速掘进施工技术,实施探、测一体化,扫孔冲煤等新工艺,实现快速测报、消突,安全顺利揭穿共10层煤,工程实践表明:... 为了缩短了揭煤工期、加快成井速度,在淮北桃园煤矿扩建工程新副立井井筒、揭穿多层深水平突出煤层的施工中,采用突出煤层快速掘进施工技术,实施探、测一体化,扫孔冲煤等新工艺,实现快速测报、消突,安全顺利揭穿共10层煤,工程实践表明:距煤垂距10 m的探、测煤一体化工艺提高了测定的准确度,节约了5 m的测压工序及指标钻测时间;扫孔冲煤工艺是立井井筒揭穿突出煤层钻孔排放措施的制胜环节。 展开更多
关键词 立井多层穿煤 防治煤与瓦斯突出 快速消突
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Reservoir reconstruction technologies for coalbed methane recovery in deep and multiple seams 被引量:11
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作者 Wang Liang Liu Shimin +3 位作者 Cheng Yuanping Yin Guangzhi Zhang Dongming Guo Pinkun 《International Journal of Mining Science and Technology》 SCIE EI CSCD 2017年第2期277-284,共8页
Multiple coal seams widely develop in the deep Chinese coal-bearing strata. Ground in situ stress and coal seam gas pressure increase continuously with the increase of the mining depth, and coal and gas outburst disas... Multiple coal seams widely develop in the deep Chinese coal-bearing strata. Ground in situ stress and coal seam gas pressure increase continuously with the increase of the mining depth, and coal and gas outburst disasters become increasingly severe. When the coal is very deep, the gas content and pressure will elevate and thus coal seams tends to outburst-prone seams. The safety and economics of exploited firstmined coal seams are tremendously restricted. Meanwhile, the multiple seams occurrence conditions resulted in different methane pressure systems in the coal-bearing strata, which made the reservoir reconstruction of coal difficult. Given the characteristics of low saturation, low permeability, strong anisotropy and soft coal of Chinese coal seams, a single hydraulic fracturing surface well for reservoir reconstruction to pre-drain the coalbed methane(CBM) of multiple seams concurrently under the different gas pressure systems has not yet gained any breakthroughs. Based on analyses of the main features of deep CBM reservoirs in China, current gas control methods and the existing challenges in deep and multiple seams, we proposed a new technology for deep CBM reservoir reconstruction to realize simultaneous high-efficiency coal mining and gas extraction. In particular, we determined the first-mined seam according to the principles of effectiveness and economics, and used hydraulic fracturing surface well to reconstruct the first-mined seam which enlarges the selection range of the first-mined seam. During the process of mining first-mined seam, adjacent coal seams could be reconstructed under the mining effect which promoted high-efficiency pressure relief gas extraction by using spatial and comprehensive gas drainage methods(combination of underground and ground CBM extraction methods). A typical integrated reservoir reconstruction technology, ‘‘One well for triple use", was detailed introduced and successfully applied in the Luling coal mine. The application showed that the proposed technology could effectively promote coal mining safety and simultaneously high-efficiency gas extraction. 展开更多
关键词 Reservoir reconstruction Coalbed methane Multiple seam Surface well Gas drainage
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Optimization for Production of Intracellular Polysaccharide from Cordyceps ophioglossoides L2 in Submerged Culture and Its Antioxidant Activities in vitro 被引量:2
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作者 许勤勤 刘振华 +3 位作者 孙一晟 丁忠杰 吕龙贤 李永泉 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2012年第2期294-301,共8页
Cordyceps ophioglossoides is a valuable traditional medicinal material.We have found that intracellular polysaccharide(IPS) is the major biologically active ingredient in Cordyceps ophioglossoides.This study is the fi... Cordyceps ophioglossoides is a valuable traditional medicinal material.We have found that intracellular polysaccharide(IPS) is the major biologically active ingredient in Cordyceps ophioglossoides.This study is the first time to optimize the yield of IPS from Cordyceps ophioglossoides.The optimal medium for IPS production consists of glucose 54.50 g·L·1,yeast powder 25.50 g·L·1,NaH2PO4 0.4 g·L·1 and K2HPO4 0.4 g·L·1.The suggested culture conditions are 24 ℃,initial pH 4.5 with a rotary speed of 120 r·min·1 for 168 h.The yield of IPS is 737.93 mg·L·1,which is 50% higher than the yield under the conditions prior to optimization.The anti-oxidative activities of IPS in Cordyceps ophioglossoides L2 are also characterized using various in vitro assay.The anti-oxidative activity may explain the reason why IPS from Cordyceps ophioglossoides can be used to fight against neurodegenerative dis-eases and menopausal symptoms. 展开更多
关键词 antioxidant activity Cordyceps ophioglossoides L2 intracellular polysaccharide submerged culture optimization
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Solutions to Right Conflicts and Integrated Protection of Diverse Interests in Real EstateDevelopment and Operation
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作者 CHENG Yao 《International English Education Research》 2016年第1期7-9,共3页
In the development and operation of real estate, real estate development enterprises as the principal subject would often establish contractual relationships with subjects of diverse interests including removed househ... In the development and operation of real estate, real estate development enterprises as the principal subject would often establish contractual relationships with subjects of diverse interests including removed households, banks, construction project contractors, and buyers. At times, conflicts of interests might occur among these contractual subjects requesting civil and commercial claims of the same subject matter based on agreements or legal rights. As for the causes of these conflicts and their solutions, a majority of existing researches still stay at the superficial causes from the perspective of civil and commercial law, and the solution of determining the order of priority of compensation of related rights. Due to the lack of research into deep-seated reasons and solutions from the perspective of economic law, the current legislative and judicial approaches to this kind of problems tend to give more protection to the rights of one subject while lack sufficient attention to other subjects. This paper attempts to carry out analyses and research on the causes and solutions to this kind of conflicts from the perspective of economic law, to achieve integrated protection of diverse interests in real estate development and operation so as to better safeguard the order in real estate development and operation and facilitate the healthy and ordered development of the real estate industry. 展开更多
关键词 real estate development and operation right conflicts economic law integrated protection
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