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基于断裂力学的浅埋工作面过沟谷地形上坡段切顶机理分析

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矿业研究与开发 2024年第4期44卷 97-106页

作者：杨登峰李小双马天辉谢生荣青岛理工大学理学院山东青岛市266520 常州大学城市建设学院江苏常州市213164 大连理工大学海岸和近海工程国家重点实验室辽宁大连市116024 中国矿业大学(北京)能源与矿业学院北京100083

浅埋煤层工作面推进至沟谷地形上坡段时,易出现关键层破断块体沿煤壁整体滑落失稳的大范围动载矿压灾害。根据沟谷上坡段顶板破断特征,基于断裂力学分析方法构建力学模型,探讨了顶板失稳的力学机理及基本顶破断失稳条件,获得了顶板来压... 详细信息

浅埋煤层工作面推进至沟谷地形上坡段时,易出现关键层破断块体沿煤壁整体滑落失稳的大范围动载矿压灾害。根据沟谷上坡段顶板破断特征,基于断裂力学分析方法构建力学模型,探讨了顶板失稳的力学机理及基本顶破断失稳条件,获得了顶板来压步距及支架工作阻力的计算公式,并对各关键致灾因素进行了分析。研究结果表明:随着工作面推进,基本顶损伤区裂纹尖端的集中应力和应力强度因子增大,当应力强度因子增大到临界值时,悬臂梁破断工作面来压;沟谷坡角大小对来压步距及支架工作阻力起主要作用,损伤区裂纹长度、基本顶厚度、断裂韧性等因素也对其有较大影响;通过在麻地梁煤矿2103工作面进行现场监测,对理论分析结果进行了验证,进一步分析了支架阻力的合理值。研究工作提高了工作面过沟谷地形上坡段顶板控制的准确性,能够有效促进矿井的安全生产。

关键词：浅埋煤层沟谷地形上坡段断裂力学支架工作阻力

天水市农业固体废弃物资源化利用现状与对策研究

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农业技术与装备 2024年第7期 40-42页

作者：李小东王伟马天惠天水市生态环境综合事务中心甘肃天水741000 天水市救灾物资储备中心甘肃天水741000 天水市蔬菜产业办公室甘肃天水741000

通过对农业固体废弃物相关概念和特点的综述,对天水市农业固体废弃物发展现状的调查,厘清了天水市农业固体废弃物综合现状及利用技术模式,分析了存在的问题,提出了相关对策建议。

关键词：农业固体废弃物资源化利用现状天水市

On stress-forecasting strategy of earthquakes from stress buildup,stress shadow and stress transfer(SSS) based on numerical approach

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Earthquake Science 2009年第1期22卷 53-62页

作者： Chunan Tang tianhui ma Xiaoli Ding Center for Rock Instability and Seismicity Research Northeastern University Shenyang China Department of Land Surveying and Geo-Informatics Hong Kong Polytechnic University Kowloon Hong Kong China

Global Positioning System （GPS） and Interferometric Synthetic Aperture Radar （InSAR）, used for monitoring crust deformation, are found to be very promising in earthquake prediction subject to stress-forecasting. However, it is recognized that unless we can give reasonable explanations of these curious precursory phenomena that continue to be serendipitously observed from time to time, such high technology of GPS or InSAR is difficult to be efficiently used. Therefore, a proper model revealing the relation between earthquake evolution and stress variation, such as the phenomena of stress buildup, stress shadow and stress transfer （SSS）, is crucial to the GPS or InSAR based earthquake prediction. Here we address this question through a numerical approach of earthquake development using an intuitive physical model with a map-like configuration of discontinuous fault system. The simulation provides a physical basis for the principle of stress-forecasting of earthquakes based on SSS and for the application of GPS or InSAR in earthquake prediction. The observed SSS associated phenomena with images of stress distribution during the failure process can be continuously simulated. It is shown that the SSS are better indicators of earthquake precursors than that of seismic foreshocks, suggesting a predictability of earthquakes based on stress-forecasting strategy.

关键词： stress-forecasting earthquake stress buildup stress shadow stress transfer

Advanced lanthanide doped upconversion nanomaterials for lasing emission

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Journal of Rare Earths 2022年第5期40卷 687-695,I0001页

作者： Yunfei Shang Tong Chen tianhui ma Shuwei Hao Weiqiang Lv Dechang Jia Chunhui Yang School of materials Science and Engineering Harbin Institute of TechnologyHarbin 150001China MIIT Key Laboratory of Critical materials Technology for New Energy Conversion and Storage School of Chemistry and Chemical EngineeringHarbin Institute of TechnologyHarbin 150001China College of materials and Chemical Engineering Heilongjiang Institute of TechnologyHarbin 150050China State Key Laboratory of Urban Water Resource and Environment Harbin Institute of TechnologyHarbin 150001China Yangtze Delta Region Institute(Huzhou)&School of Physics University of Electronic Science and Technology of ChinaHuzhou 313001China

Microlasers are narrow-band and coherent light from small cavities,which have been widely applied in biomedicine,optical interconnection,integration devices,*** doped upconversion materials are potential gain media for microlasers from near infrared(NIR)to visible and UV regimes due to their multi ladder-like metastable energy levels and superior optical frequency conversion *** optical feedback from photon scattering of the porous upconversion nanoparticles clusters has been reported to produce upconversion random *** light bouncing back and forth between two reflective surfaces or internal surface has been utilized to achieve modulated upconversion lasing *** addition,photon lattices and plasmonic cavities with enhanced electromagnetic fields can amplify the upconversion process within the sub-diffraction volumes and produce highly efficient upconverting *** this review,the recent advances on using lanthanide doped upconversion materials for random,whispering gallery mode(WGM)/Fabry-Perot(FP)cavity and photon lattice/plasmonic cavity modulated upconversion microlasers are *** challenges and future directions of the upconverting lasers are also discussed.

关键词： Lanthanide Upconversion Microlaser Microcavity Rare earths

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中远红外及太赫兹波段非线性晶体硒化镓

硅酸盐学报 2017年第10期45卷 1402-1409页

作者：杨春晖马天慧朱崇强雷作涛哈尔滨工业大学化工与化学学院黑龙江工程学院材料与化学工程学院

中远红外及太赫兹波段激光在国防和民用领域都有非常突出和迫切的需求,硒化镓(GaSe)晶体是一综合性能优异的红外非线性光学材料,通过差频产生和光学参量振荡可实现这两个波段的可调谐激光输出。综述了GaSe晶体及掺杂晶体在合成、生长、... 详细信息

中远红外及太赫兹波段激光在国防和民用领域都有非常突出和迫切的需求,硒化镓(GaSe)晶体是一综合性能优异的红外非线性光学材料,通过差频产生和光学参量振荡可实现这两个波段的可调谐激光输出。综述了GaSe晶体及掺杂晶体在合成、生长、掺杂性能及差频产生中远红外及太赫兹辐射方面的最新研究成果,重点介绍了GaSe晶体及掺杂晶体的光学、力学性能,非线性性能及它们在频率转换方面的应用性能。通过全面的分析找出综合性能最优的掺杂晶体种类。

关键词：硒化镓晶体中远红外激光非线性光学材料太赫兹

Li-Ga-S体系热力学函数的第一性原理计算

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计算物理 2013年第6期30卷 931-935页

作者：马天慧马天方孙亮朱崇强牡丹江师范学院化学化工学院黑龙江牡丹江157011 宜宾学院物理与电子工程学院四川宜宾644000 哈尔滨工业大学化工学院黑龙江哈尔滨150001

采用第一性原理的平面波赝势法计算Li-Ga-S体系LiGa,Li2S,GaS,Ga2S3和LiGaS2的热力学数据,分析可能发生的化学反应,其中4个化学反应可以生成目标产物LiGaS2.单质直接化合生成LiGaS2的反应自由能变较高,Li2S与Ga2S3化合生成LiGaS2的反应... 详细信息

采用第一性原理的平面波赝势法计算Li-Ga-S体系LiGa,Li2S,GaS,Ga2S3和LiGaS2的热力学数据,分析可能发生的化学反应,其中4个化学反应可以生成目标产物LiGaS2.单质直接化合生成LiGaS2的反应自由能变较高,Li2S与Ga2S3化合生成LiGaS2的反应自由能变随温度升高而降低,但体系很难获得Ga2S3,LiGa与S生成LiGaS2和Li2S与GaS化合生成LiGaS2的自由能变较小,且体系生成Li2S,GaS和LiGa的自由能变也较小,由此推断LiGaS2多晶原料可以通过后两个反应获得.

关键词：键布居德拜温度自由能结合能生成焓

Haploidentical hematopoietic cell transplantation with or without an unrelated cord blood unit for adult acute myeloid leukemia:a multicenter,randomized,open-label,phase 3 trial

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Signal Transduction and Targeted Therapy 2024年第6期9卷 2669-2678页

作者： Biqi Zhou Jia Chen tianhui Liu Yishan Ye Yanming Zhang Yiyang Ding Hong Liu MingQing Zhu Xiao ma Xiaoli Li Longfei Zhao Zhihong Lin He Huang Yang Xu Depei Wu National Clinical Research Center for Hematologic Diseases Jiangsu Institute of HematologyThe First Affiliated Hospital of Soochow UniversitySuzhouChina Institute of Blood and marrow Transplantation Collaborative Innovation Center of HematologySoochow UniversitySuzhouChina Bone marrow Transplantation Center The First Affiliated HospitalZhejiang University School of MedicineHangzhouZhejiangChina Department of Hematology The Affiliated Huai’an Hospital of Xuzhou Medical University and The Second People’s Hospital of Huai’anHuai’anChina Soochow Hopes Hematology Hospital SuzhouChina Department of Hematology Hygeia Suzhou Yongding HospitalSuzhouChina

Coinfusion of unrelated cord blood(UCB)units in haploidentical hematopoietic cell transplantation(haplo-HCT)(haplo-cord HCT)for hematopoietic malignancies showed promising results in previous reports,but the efficiency of haplo-cord HCT in acute myeloid leukemia(AML)still lacks sufficient *** multicenter,randomized,phase 3 trial(*** NCT03719534)aimed to assess the efficacy and safety of haplo-cord HCT in AML patients.A total of 268 eligible patients aged 18-60 years,diagnosed with measurable residual disease in AML(excluding acute promyelocytic leukemia),with available haploidentical donors and suitable for allotransplantation,were randomly allocated(1:1)to receive haplo-cord HCT(n=134)or haplo-HCT(n=134).The 3-year overall survival(OS)was the primary endpoint in this *** median follow-up was 36.50 months(IQR 24.75-46.50).The 3-year OS of Haplo-cord HCT group was better than haplo-HCT group(80.5%,95%confidence interval[CI]:73.7-87.9 vs.67.8%95%CI 60.0-76.5,p=0.013).Favorable progression-free survival(70.3%,95%CI 62.6-78.8 vs.57.6%,95%CI 49.6-67.0,p=0.012)and cumulative incidence of relapse(12.1%,95%CI 12.0-12.2 vs.30.3%,95%CI 30.1-30.4,p=0.024)were observed in haplo-cord HCT *** 3-4 adverse events(AEs)within two years posttransplantation in the two groups were ***-cord HCT patients exhibited a faster cumulative incidence of neutrophil recovery(p=0.026)and increased T-cell reconstitution in the early period ***-cord HCT can improve OS in AML patients without excessive AEs,which may exert additional benefits for recipients of haplo-HCT.

关键词： hematopoietic acute phase

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水力压裂裂缝穿层及扭转扩展的三维模拟分析

岩石力学与工程学报 2010年第A01期29卷 3208-3215页

作者：李连崇梁正召李根马天辉大连理工大学海岸与近海工程国家重点实验室辽宁大连116024

应用并行有限元程序对水力压裂过程进行真三维数值模拟,实现对压裂裂缝起裂、扩展及扩展中的穿层、扭转行为的全过程分析;数值计算中无需假定压裂裂缝的起裂位置和扩展路径,即可根据实际岩体水力学模型的力学、水力学等边界条件,自动标... 详细信息

应用并行有限元程序对水力压裂过程进行真三维数值模拟,实现对压裂裂缝起裂、扩展及扩展中的穿层、扭转行为的全过程分析;数值计算中无需假定压裂裂缝的起裂位置和扩展路径,即可根据实际岩体水力学模型的力学、水力学等边界条件,自动标定出压裂裂缝的三维扩展模式,并显示出该并行有限元程序对复杂地质力学条件下水力压裂过程三维模拟分析的适用性。通过对压裂裂缝扩展过程中孔隙压力分布、裂缝几何形状和尺寸的演化进行了解读,显示出压裂裂缝的扩展模式与地层分布密切相关。当生产层很薄或生产层与上下阻挡层岩性差别较大时,裂缝穿层现象突出,可能会出现压裂实际缝长远远小于设计缝长的现象;近场地应力差异、地层分布特征及岩体细观非均匀性都有可能诱发压裂裂缝扭转扩张。分析结果对水力压裂施工设计具有一定的参考价值。

关键词：岩石力学水力压裂并行计算裂缝数值模拟

荒沟抽水蓄能电站地下厂房开挖过程微震活动特征与围岩稳定性研究

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隧道建设（中英文） 2019年第5期39卷 775-782页

作者：高乔马克唐春安马天辉大连理工大学岩石破裂与失稳研究中心辽宁大连116024 大连理工大学海岸和近海工程国家重点实验室辽宁大连116023

牡丹江荒沟抽水蓄能电站地下厂房具有典型的"大跨度、高边墙、多洞室交叉"的工程结构特点,在陡倾结构面、中等地应力等复杂地质条件和强卸荷开挖的影响下,洞室围岩片帮、掉块等局部稳定性问题突出。针对此问题,构建荒沟抽水蓄能电站地... 详细信息

牡丹江荒沟抽水蓄能电站地下厂房具有典型的"大跨度、高边墙、多洞室交叉"的工程结构特点,在陡倾结构面、中等地应力等复杂地质条件和强卸荷开挖的影响下,洞室围岩片帮、掉块等局部稳定性问题突出。针对此问题,构建荒沟抽水蓄能电站地下厂房微震监测系统,对地下厂房开挖卸荷过程进行实时监测,揭示围岩内部岩石微破裂的萌生演化过程及其对围岩稳定性的影响。结果表明:1)开挖卸荷的强施工扰动引起的围岩高能量释放,导致主厂房上游边墙围岩内的断层破碎带局部损伤加剧,诱发大量微震事件;2)微震事件在主厂房上游侧拱肩区域沿断层走向呈条带状分布,且在厂房下游侧边墙与3#支洞交汇的洞室结构薄弱部位聚集;3)识别主厂房上游边墙桩号厂左0+20m至厂左0+80m段是围岩潜在失稳区域。

关键词：抽水蓄能电站地下厂房微震监测围岩稳定岩体损伤