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Model test on support scheme for carbonaceous slate tunnel in high geostress zone at high depth

Journal of Mountain Science 2021年第3期18卷 764-778页

作者： TAO Zhi-gang REN Shu-lin LI Gan xu hao-tian LUO Sen-lin HE Man-chao State Key Laboratory for Geomechanics&Deep Underground Engineering China University of Mining and TechnologyBeijing 100083China School of Mechanics and Civil Engineering China University of Mining and TechnologyBeijing 100083China State Key Laboratory of Hydroscience and Engineering Tsinghua UniversityBeijing 100084China

The Muzhailing extra-long highway tunnel and corresponding inclined shafts in Lanzhou,Gansu Province,China passes through structurally complex carbonaceous slate that is under high ground ***-designed and effective support is of high importance for achieving safe and efficient tunnel *** No.2 inclined shaft of Muzhailing Tunnel was taken as the engineering background prototype,for which,a similar model test was conducted to evaluate the effect of highly pretightened constant resistance(NPR,Negative Poisson’s Ratio)anchor cable support provision to the geologically complex carbonaceous slate at different *** schemes were proposed during testing:one scheme was without support and the second was with asymmetric support from highly pre-tightened constant resistance anchor *** speckle displacement analysis system and micro-groundstress sensors were employed to measure the deformation and shear stress distribution of the *** results demonstrated that through the second support scheme,the deformation of the surrounding rock could be effectively ameliorated,while this support scheme was applied on the project site of the No.2 inclined shaft,to explore the rationality of the scheme through field engineering ***-site monitoring indicated that the deformation of the surrounding rock was within the reasonable design range and the problem of severe tunnel deformation was effectively *** research methods and related conclusions can be used as a reference for the treatment of large deformation problems in deep-buried soft rock tunnels.

关键词： Tunnel engineering Support design Carbonaceous slate Similar simulation NPR anchor cable

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Negative Poisson's ratio and peripheral strain of an NPR anchor cable

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Journal of Mountain Science 2022年第8期19卷 2435-2448页

作者： TAO Zhi-gang xu hao-tian REN Shu-lin GUO Long-ji QIN Ke ZHU Yi-fei State Key Laboratory for Geomechanics&Deep Underground Engineering Beijing 100083China School of Mechanics and Civil Engineering China University of Mining&TechnologyBeijing 100083China

Materials with a negative Poisson’s ratio effect perform significantly better than traditional materials for rock mass impact resistance,shear resistance,and energy *** on these advantages,a negative Poisson’s ratio anchor cable(NPR anchor cable)with high elongation and constant resistance was developed and successfully applied in the field of mine disaster ***,theoretical and experimental research on the negative Poisson’s ratio effect and peripheral strain characteristics of NPR anchor cables is currently *** study used several theories and methods,such as static tensile,peripheral strain measurement,and static negative Poisson’s ratio measurement,to investigate the radial deformation law of an NPR anchor cable and the negative Poisson’s ratio *** results elucidated constant resistance changes in an NPR anchor cable during operation,the motion of the constant resistance body in the constant resistance sleeve,and the deformation law of the constant resistance *** Poisson’s ratio characteristics of the NPR anchor cable and its superior energy absorption characteristics were verified and it provided a theoretical and experimental basis for energy absorption mechanisms of an NPR anchor cable.

关键词： NPR anchor cable Static tensile test Negative Poisson’s ratio Energy absorption

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Stability analysis of open-pit gold mine slopes and optimization of mining scheme in Inner Mongolia,China

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Journal of Mountain Science 2020年第12期17卷 2997-3011页

作者： REN Shu-lin TAO Zhi-gang HE Man-chao PANG Shi-hui LI Meng-nan xu hao-tian State Key Laboratory for Geomechanics&Deep Underground Engineering Beijing 100083China School of Mechanics and Civil Engineering China University of Mining&TechnologyBeijing 100083China

The geological structure of the Changshanhao open-pit mine in Urad Middle Banner,Inner Mongolia,China is extremely complicated,and slope instability has frequently occurred in various forms,such as wedge sliding,bedding sliding,and toppling *** order to study the failure mechanisms of these slopes,the geological structure and mechanical rock properties were investigated based on field investigations and laboratory *** models for the present mining area and final mining area of the original scheme were established to analyze slope *** results showed that the unique geomorphological characteristics of the mining area were generated by geological tectonism,and the north side of the stope is an anti-dip layered rock slope and the south side is a dip layered rock *** failure is the consequence of endogenic and exogenic integration,including physical and mechanical properties of the rock mass,geological structures such as faults and joints,and human-caused factors such as blasting and excavation *** the original excavation scheme was redesigned mainly by optimizing the slope angle and decreasing the final mining depth to maintain slope ***,the Monte Carlo method was used to analyze the reliability of the slope angle optimization *** open-pit mine excavation plan that meets the stability requirements was obtained eventually.

关键词： Open pit mine Slope stability Numerical simulation Excavation scheme

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Pancreatic head region lymph node tuberculosis mimicking pancreatic solid pseudopapillary tumor

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Chinese Medical Journal 2013年第5期126卷 976-977页

作者： xu Quan LIU hao tian Yan-tao Department of Abdominal Surgery Cancer Institute & CancerHospital Chinese Academy of Medical Sciences (CAMS) Beijing100021 China

Tuberculosis （TB） is a common disease in developing countries, and even in developed countries; its incidence is rising. Pancreatic head regional lymph node TB is uncommon, and isolated involvement is rare. Pre-operative diagnosis of pancreatic head regional lymph node TB is difficult and may mimic pancreatic malignant or benign lesions. We herein present a case of lymph node TB in the pancreatic head region mimicking a pancreatic solid pseudopapillary tumor in a 40-year-old female patient.

关键词： tuberculosis pancreatic solid pseudopapillary tumor diagnosis

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时空耦合畸变对超快超强激光参数测试及性能评估的影响

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物理学报 2022年第17期71卷 218-226页

作者：龙天洋李伟许浩天王逍四川大学物理学院成都610044 中国工程物理研究院激光聚变研究中心绵阳621900 中国科学技术大学光学与光学工程系合肥230026 山东大学(威海)空间科学与物理学院威海264000 中国工程物理研究院研究生院北京100088

在大型超快超强激光系统中,随着光谱带宽及光束口径的增加,时空耦合畸变会变得越来越显著,该效应不仅会使光束质量恶化、影响激光的聚焦功率密度,而且会使常规的激光远场性能的评估手段失效.本文以激光器中常用的扩束透镜组为例分析了... 详细信息

在大型超快超强激光系统中,随着光谱带宽及光束口径的增加,时空耦合畸变会变得越来越显著,该效应不仅会使光束质量恶化、影响激光的聚焦功率密度,而且会使常规的激光远场性能的评估手段失效.本文以激光器中常用的扩束透镜组为例分析了时空耦合畸变给激光参数测量及激光性能评估带来的影响.结果表明,在一个超短脉冲激光系统中,一对普通的扩束透镜组引入的时空耦合畸变不仅会使远场峰值功率密度急剧下降,还会导致单次自相关仪在近场处测得的脉宽与远场处的实际脉宽相差超过10倍,而这种情况下利用近场脉宽测试值估算远场处的聚焦功率密度会比真实值高出一个量级.研究结果可以为激光器的优化设计、激光脉冲参数的精确表征以及相关的物理实验提供参考.

关键词：超快激光时空耦合畸变单次自相关

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政策工具视域下我国专业学位研究生政策的三维分析(1990-2020)

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黑龙江高教研究 2022年第11期40卷 51-56页

作者：张天雪徐浩天浙江师范大学教育改革与发展研究院浙江金华321004 浙江师范大学教师教育学院浙江金华321004

发展专业学位研究生教育是当前研究生教育改革的方向和重点。政策既是导向,也是手段,基于政策工具的视角,选取1990-2020年95份中央层面专业学位研究生教育政策文件为样本,以政策工具、政策要素、政策时间等三维为分析框架,对政策文本进... 详细信息

发展专业学位研究生教育是当前研究生教育改革的方向和重点。政策既是导向,也是手段,基于政策工具的视角,选取1990-2020年95份中央层面专业学位研究生教育政策文件为样本,以政策工具、政策要素、政策时间等三维为分析框架,对政策文本进行文本编码分析。结果表明:专业学位研究生教育政策的出台具有明显的阶段性、政策工具结构略显失衡、政策工具内在构成要素不尽合理、政策工具和政策要素的契合度不高。在制定我国专业学位研究生教育政策时应保证政策的持续性,调整政策工具外在结构,优化政策工具内部结构,完善政策要素内容,提升政策工具与政策要素的契合度。

关键词：专业学位研究生政策工具文本分析

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基于复杂网络的中国股票市场统计特征分析

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山东大学学报（理学版） 2017年第5期52卷 41-48页

作者：许忠好李天奇华东师范大学统计学院上海200241

为分析中国股票市场统计特征,利用通过滑动时间窗口建立相关性网络序列,通过超度量矩阵、最小生成树和阈值法等方法转化相关性网络,建立相关性网络的统计特征序列,并分析各个统计特征间的关联与影响。研究结果表明,上证指数收益率对股... 详细信息

为分析中国股票市场统计特征,利用通过滑动时间窗口建立相关性网络序列,通过超度量矩阵、最小生成树和阈值法等方法转化相关性网络,建立相关性网络的统计特征序列,并分析各个统计特征间的关联与影响。研究结果表明,上证指数收益率对股票相关性网络的聚类系数有负效应,对平均最短路径有正效应,表明中国资本市场上升的动量具有分散化的特征;同时,相关性网络的聚类系数对网络同步性有正效应,平均最短路径则对网络同步性有负效应。

关键词：聚类系数网络同步性股票相关性

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Chemoenzymatic Synthesis of Ramosetron Hydrochloride

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Chemical Research in Chinese Universities 2012年第1期28卷 70-72页

作者： LIU Qing-wen1 , xu hao1, tian Hua1, ZHENG Liang-yu2 and ZHANG Suo-qin1 1. College of Chemistry, 2. Key Laboratory for Molecular Enzymology and Engineering, Ministry of Education, Jilin University, Changchun 130012, P. R. China College of Chemistry Jilin University 130012 Jilin University Key Laboratory for Molecular Enzymology and Engineering Ministry of Education 130012

A new method for the synthesis of ramosetron hydrochloride, the most wildly used 5-HT3 receptor antagonist, was reported. The intermediate 8 was obtained in a high e.e. value via lipase catalyzed hydrolytic kinetic resolution. Then enantiomerically pure ramosetron hydrochloride was synthesized in two steps with excellent yield （the total yield is 24.6%）. The method provides a new environment friendly and atom economy way to synthesize enantiomerically pure ramosetron.

关键词： Ramosetron hydrochloride Chemical enzymatic synthesis Atom economy

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Role of iron ore in enhancing gasification of iron coke:Structural evolution,influence mechanism and kinetic analysis

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International Journal of Minerals,Metallurgy and Materials 2025年第1期32卷 58-69页

作者： Jie Wang Wei Wang xuheng Chen Junfang Bao Qiuyue hao Heng Zheng Runsheng xu School of Chemistry and Materials Science Hubei Engineering UniversityXiaogan 432000China Key Laboratory for Ferrous Metallurgy and Resources Utilization of Ministry of Education Wuhan University of Science and TechnologyWuhan 430081China Institue of Ironmaking Technology Baosteel Central Research InstituteShanghai 201999China State Key Laboratory of Advanced Metallurgy University of Science and Technology BeijingBeijing 100083China

The utilization of iron coke provides a green pathway for low-carbon *** uncover the influence mechanism of iron ore on the behavior and kinetics of iron coke gasification,the effect of iron ore on the microstructure of iron coke was ***,a comparative study of the gasification reactions between iron coke and coke was conducted through non-isothermal thermogravimetric *** findings indicate that compared to coke,iron coke exhibits an augmentation in micropores and specific surface area,and the micropores further extend and *** provides more adsorption sites for CO_(2) molecules during the gasification process,resulting in a reduction in the initial gasification temperature of iron *** the heating rate in non-isothermal gasification can enhance the reactivity of iron *** metallic iron reduced from iron ore is embedded in the carbon matrix,reducing the orderliness of the carbon structure,which is primarily responsible for the heightened reactivity of the carbon *** kinetic study indicates that the random pore model can effectively represent the gasification process of iron coke due to its rich pore ***,as the proportion of iron ore increases,the activation energy for the carbon gasification gradually decreases,from 246.2 kJ/mol for coke to 192.5 kJ/mol for iron coke 15wt%.

关键词： low-carbon ironmaking iron coke gasification structural evolution kinetic model

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利用羟胺实现城市污水短程硝化最优投加点选择

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中国环境科学 2021年第8期41卷 3576-3583页

作者：徐昊天张树军杜睿彭永臻北京工业大学城镇污水深度处理与资源化利用技术国家工程实验室北京100124 北京城市排水集团有限责任公司科技研发中心北京100022

模拟缺氧/好氧(A/O)模式运行的序批式活性污泥法(SBR)处理系统,探究利用羟胺实现城市污水短程硝化的投加点优化.批次实验发现,溶解氧存在会降低羟胺对亚硝酸盐氧化菌(NOB)抑制效果的(20±0.5)%.此外,相较于未经缺氧处理和延长缺氧时间(>... 详细信息

模拟缺氧/好氧(A/O)模式运行的序批式活性污泥法(SBR)处理系统,探究利用羟胺实现城市污水短程硝化的投加点优化.批次实验发现,溶解氧存在会降低羟胺对亚硝酸盐氧化菌(NOB)抑制效果的(20±0.5)%.此外,相较于未经缺氧处理和延长缺氧时间(>15min)处理,缺氧时间为1~5min可提高NOB活性抑制率13%~25%.长期试验表明,在缺氧段末投加羟胺的短程硝化系统维持NO_(2)^(-)-N积累率92%以上,而在好氧阶段投加羟胺的系统NO_(2)^(-)-N积累率逐渐降低.qPCR分析证明,羟胺投加点为缺氧段末可在充分抑制NOB基础上,降低对氨氧化菌(AOB)的抑制作用,从而有利于AOB成为优势菌群结构.本研究为优化羟胺投加点和稳定维持短程硝化提供理论基础.

关键词：羟胺城市污水短程硝化投加点缺氧/好氧(A/O)模式

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