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矿用胶囊式救生舱设计与仿真分析

工业安全与环保 2024年第4期50卷 34-38页

作者：伊海洋张才应急管理部四川消防研究所四川成都610036

矿用救生舱是应对煤矿救援的重要设备,为增强救生舱的整体安全性,根据我国现有煤矿地质特点,结合国内外煤矿火灾救援成功案例,提出一种矿用胶囊式救生舱结构。借助NX软件对救生舱进行了结构设计,集成了引导、容纳、缓冲、防火及通信等功... 详细信息

矿用救生舱是应对煤矿救援的重要设备,为增强救生舱的整体安全性,根据我国现有煤矿地质特点,结合国内外煤矿火灾救援成功案例,提出一种矿用胶囊式救生舱结构。借助NX软件对救生舱进行了结构设计,集成了引导、容纳、缓冲、防火及通信等功能,同时,参照已有防爆液压绞车,利用ANSYS对救生舱的救援工况进行了安全分析。结果表明,该救生舱安全裕量大,能够利用常规液压绞车系统,安全实现受困人员的救援。

关键词：矿用机械火灾救援救生舱安全分析

青藏高原西北部班公湖流域夏季主要水体H-O同位素组成及其影响因素

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现代地质 2024年第2期38卷 427-436页

作者：邵玉祥严步青刘旭蒋钦陈文彬龚康易海洋李博中国地质调查局军民融合地质调查中心四川成都610036 中国地质大学(武汉)地球科学学院湖北武汉430073 中国地质大学(北京)地球科学与资源学院北京100083

作为高寒内陆区的青藏高原西北部班公湖流域水文数据资料较为匮乏,导致对区域水循环过程和气候环境的认识不够深入,氢氧稳定同位素示踪技术可为解决该问题提供理想途径。本文系统分析班公湖流域夏季含湖水、河水、冰川融水和地下水4种... 详细信息

作为高寒内陆区的青藏高原西北部班公湖流域水文数据资料较为匮乏,导致对区域水循环过程和气候环境的认识不够深入,氢氧稳定同位素示踪技术可为解决该问题提供理想途径。本文系统分析班公湖流域夏季含湖水、河水、冰川融水和地下水4种不同类型的水体中氢氧同位素的组成,阐释水体氢氧同位素、氘盈余参数沿程变化的特征及其与水体矿化度、高程、经纬度和全球大气降雨线之间的关系,并进一步剖析同位素组成变化的控制因素。结果显示,水体中δ^(2)H和δ^(18)O的波动范围分别为-112.37‰~-24.90‰和-14.84‰~2.01‰,平均值及标准差分别为-76.73‰±26.49‰和-8.43‰±5.24‰。湖水δ^(2)H和δ^(18)O相对其他水体富集,测定结果更偏正值,冰川融水δ^(2)H和δ^(18)O相对其他水体更为贫化。流域水体氢氧同位素的大陆效应总体不明显,部分水体有一定高程效应体现。水体氢氧同位素演化趋势表明,冰川融水与全球大气水线接近,易受大气降雨影响。同时其他水体线的较小截距和斜率值,表明大气降雨不是这些水体的直接补给源。河流沿程的水体δ^(2)H和δ^(18)O呈递增趋势,越远离冰川融水补给端的河水和湖水值越偏正,反映强蒸发的特点。水体氘盈余参数及其与矿化度之间的关系也指示蒸发作用是影响该区域水体氢氧同位素变化的主要因素。

关键词：班公湖流域氢氧同位素氘盈余参数空间特征同位素效应

Deformation characteristics and safety assessment of a high-speed railway induced by undercutting metro tunnel excavation

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Journal of Rock Mechanics and Geotechnical Engineering 2019年第1期11卷 88-98页

作者： Wangping Qian Taiyue Qi Yunjian Zhao yizhou Le haiyang yi Key Laboratory of Transportation Tunnel Engineering Ministry of Education Southwest Jiaotong University School of Civil Engineering Southwest Jiao tong University China Railway Design Corporation China Changjiang Construction Investment Corp.Ltd. North China Institute of Science and Technology

Stratum deformation(settlement) is a challenging issue in tunnel engineering, especially when construction of metro tunnels has to undercut high-speed railway. For this purpose, we used the FLAC30 software to analyze the stratum settlement characteristics of high-speed railway at different crossing angles intersected by metro tunnel, in terms of ground settlement trough, stratum slip line and irregularity of ballastless tracks. According to the evolution of the stratum settlement at different angle regions, an optimized angle is proposed for the actual project design. In order to reduce the influence of stratum settlement on the safety of high-speed railway, an approach of safety assessment is proposed for the shield engineering undercutting high-speed railway, as per Chinese specifications using numerical results and on-site conditions. A case study is conducted for the shield tunnel section crossing the Wuhan-Guangzhou High-speed Railway between the Guangzhou North Railway Station and the Huacheng Road Station, which represents the first metro tunnel project passing below a high-speed railway in China. A series of measures is taken to ensure the safe excavation of the shield tunnel and the operation of the high-speed railway. The results can provide a technical support for performing a safety evaluation between high-speed railways and metro tunnels.

关键词： Metro tunnel excavation High-speed railway Settlement characteristics Safety assessment Numerical simulation Case application

Numerical simulation of gas flow process in mining-induced crack network

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International Journal of Mining Science and Technology 2012年第6期22卷 793-799页

作者： Zhou Hongwei Liu Jinfeng Xue Dongjie yi haiyang Xue Junhua State Key Laboratory of Coal Resources and Safe Mining China University of Mining & Technology State Key Laboratory of Deep Coal Mining and Environmental Protection Huainan Mining Group Corporation

The exploitation of coal bed methane or coal gas is one of the most effective solutions of the problem of coal gas hazard.A better understanding of gas flow in mining-induced cracks plays an important role in comprehensive development and utilization of coal gas as well as prevention of coal gas *** paper presents a case study of gas flow in mining-induced crack network regarding the situation of low permeability of coal seam.A two-dimensional physical model is constructed on the basis of geological background of mining face No.1122(1) in coal seam No.11-2,Zhangji Coal Mine,Huainan Mining Group *** mining-induced stress and cracks in overburden rocks are obtained by simulating an extraction in physical *** evolution of mining-induced cracks in the process of advancing of coal mining face is characterized and three typical crack networks are taken from digital photos by means of image ***,the numerical software named COMSOL Multiphysics is employed to simulate the process of gas flow in three representative crack *** of gas pressure at various times in mining-induced crack networks are plotted,suggesting a shape and dimension of gas accumulation area.

关键词： Gas flow Gas pressure Physical modeling Mining-induced cracks COMSOL

Effect mechanism of seepage force on the hydraulic fracture propagation

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International Journal of Coal Science & Technology 2024年第3期11卷 223-240页

作者： haiyang Wang Desheng Zhou yi Zou Peng Zheng School of Petroleum Engineering Xi’an Shiyou UniversityXi’an710065China Engineering Research Center of Development and Management for Low to Extra-Low Permeability Oil and Gas Reservoirs in West China Ministry of EducationXi’an Shiyou UniversityXi’an710065ShaanxiChina Xi’an University of Science and Technology Xi’an710054ShaanxiChina

The flow of fluid through the porous matrix of a reservoir rock applies a seepage force to the solid rock *** the seepage force exerted by fluid flow through the porous matrix of a reservoir rock has a notable influence on rock deformation and failure,its effect on hydraulic fracture(HF)propagation remains ***,in this study,we improved a traditional fluid–solid coupling method by incorporating the role of seepage force during the fracturing fluid seepage,using the discrete element ***,we validated the simulation results of the improved method by comparing them with an analytical solution of the seepage force and published experimental ***,we conducted numerical simulations in both homogeneous and heterogeneous sandstone formations to investigate the influence of seepage force on HF *** results indicate that fluid viscosity has a greater impact on the magnitude and extent of seepage force compared to injection rate,and that lower viscosity and injection rate correspond to shorter hydraulic fracture ***,seepage force influences the direction of HF propagation,causing HFs to deflect towards the side of the reservoir with weaker cementation and higher permeability.

关键词： Hydraulic fracturing Seepage force Fracture propagation Discrete element method Reservoir heterogeneity

Deformation analysis of transversely isotropic coal-rock mass with porous and cracks

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International Journal of Mining Science and Technology 2012年第6期22卷 814-820页

作者： Xue Dongjie Zhou Hongwei Kong Lin Tang Xianli Zhao Tian yi haiyang Zhao Yufeng School of Mechanics Architecture and Civil EngineeringChina University of Mining & Technology

Coal-rock as a typical sedimentary rock has obvious stratification,namely it has transversely isotropic ***,deformation leads to coal-rock mass having the characteristics of different porous and crack structures as well as local *** axial and circumferential strain' formulas of the pure coal-rock mass specimen with a single crack were derived through the establishment of equivalent mechanical model of standard cylindrical coal-rock specimen,and have been widely used to a variety of media combined different structures containing multiple *** complete stress strain curve of a real coal-rock specimen was obtained by the CTC ***,according to the comparison with the theoretical value,the theoretical mechanical model could well explain the deformation characteristics of coal-rock mass and verify its ***,following features were analyzed:strain normalized coefficient and elastic modulus(Poisson's ratio) in vertical and parallel direction to the stratification,stratification angle,porosity,pore radius,normal and tangential stiffness of crack,and the relationship of different crack width with different tangential stiffness of *** the analysis above,it substantiate this claim that the theoretical model with better reliability reflects the transversely isotropic nature of the coal-rock and the local anisotropy caused by the porous and cracks.

关键词： Coal-rock mass Transversely isotropic Porous and crack Mechanical model

Gastric cancer secreted miR 214-3p inhibits the anti-angiogenesis effect of apatinib by suppressing ferroptosis in vascular endothelial cells

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Oncology Research 2024年第3期32卷 489-502页

作者： WEIXUE WANG TONGTONG WANG YAN ZHANG TING DENG haiyang ZHANG yi BA Department of GI Medical Oncology Tanjin Medical University Cancer Institute and HospitalNational Clinical Research Center for CancerTianjin's Clinical Research Center for CancerTianjin Key Iaboratory of Digestive CancerKey Laboratory of Cancer Prevention and TherapyTianjin300060China

Diferent from necrosis,apoptosis,autophagy and other forms of cell death,ferroptosis is a mechanism that catalyzes lipid peroxidation of polyunsaturated ftty acids under the action of iron divalent or lipoxygenase,leading to cell *** is currently used in the third line standard treatment of advanced gastric cancer,targeting the anti-angiogenesis ***,Apatinib mediated ferroptosis in vascular endothelial cells has not been reported *** exosomes can be taken up into target cells to regulate tumor development,but the mechanism related to vascular endothelial cell ferroptosis has not yet been ***,we show that exosomes secreted by gastric cancer cells carry miR-214.3p into vascular endothelial cells and directdy target zinc finger protein A20 to negatively regulate ACSL4,a key enzyme of lipid peroxidation during frroptosis thereby inhibiting ferroptosis in vascular endothelial cells and reducing the eficiency of *** conclusion,inhibition of miR-214-3p can increase the sensitivity of vascular endothelial cells to Apatinib,thereby promoting the antiangiogenic efect of Apatinib,suggesting a potential combination therapy for advanced gastric cancer.

关键词： Cellular ferroptosis Exosome Tyrosine kinase inhibitor Gastrointestinal tumors miRNA

Machine learning for predicting fatigue properties of additively manufactured materials

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Chinese Journal of Aeronautics 2024年第4期37卷 1-22页

作者： Min yi Ming XUE Peihong CONG Yang SONG haiyang ZHANG Lingfeng WANG Liucheng ZHOU yinghong LI Wanlin GUO State Key Laboratory of Mechanics and Control for Aerospace Structures Nanjing University of Aeronautics and AstronauticsNanjing 210016China Institute for Frontier Science Nanjing University of Aeronautics and AstronauticsNanjing 210016China College of Aerospace Engineering Nanjing University of Aeronautics and AstronauticsNanjing 210016China Shenyang Engine Research Institute Shenyang 110015China Liaoning Key Laboratory of Impact Dynamics on Aero Engine Shenyang 110015China Science and Technology on Plasma Dynamics Laboratory Air Force Engineering UniversityXi’an 710038China

Fatigue properties of materials by Additive Manufacturing(AM) depend on many factors such as AM processing parameter, microstructure, residual stress, surface roughness, porosities, post-treatments, etc. Their evaluation inevitably requires these factors combined as many as possible, thus resulting in low efficiency and high cost. In recent years, their assessment by leveraging the power of Machine Learning(ML) has gained increasing attentions. A comprehensive overview on the state-of-the-art progress of applying ML strategies to predict fatigue properties of AM materials, as well as their dependence on AM processing and post-processing parameters such as laser power, scanning speed, layer height, hatch distance, built direction, post-heat temperature,etc., were presented. A few attempts in employing Feedforward Neural Network(FNN), Convolutional Neural Network(CNN), Adaptive Network-Based Fuzzy Inference System(ANFIS), Support Vector Machine(SVM) and Random Forest(RF) to predict fatigue life and RF to predict fatigue crack growth rate are summarized. The ML models for predicting AM materials' fatigue properties are found intrinsically similar to the commonly used ones, but are modified to involve AM features. Finally, an outlook for challenges(i.e., small dataset, multifarious features,overfitting, low interpretability, and unable extension from AM material data to structure life) and potential solutions for the ML prediction of AM materials' fatigue properties is provided.

关键词： Additive manufacturing Machine learning Fatigue life Fatigue crack growth rate Prediction

中深层煤炭地下气化的气化腔安全宽度计算方法

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煤炭科学技术 2024年第2期52卷 183-193页

作者：东振任博陈艳鹏赵宇峰陈浩陈姗姗薛俊杰张梦媛易海洋吴瀚琦中国石油勘探开发研究院北京100083 中国矿业大学深部岩土力学与地下工程国家重点实验室江苏徐州221116 华北科技学院建筑工程学院河北廊坊065201 中国石油天然气股份有限公司储气库分公司北京100101

煤炭地下气化是目前温度最高(超过1200℃)的化石能源非常规开发方式,中深层(本文指埋深800~1500 m)煤炭地下气化在提高气化压力、降低地质安全风险方面优势明显,科学预测气化腔安全宽度对保障气化稳定运行十分重要,由于目前基于可控注... 详细信息

煤炭地下气化是目前温度最高(超过1200℃)的化石能源非常规开发方式,中深层(本文指埋深800~1500 m)煤炭地下气化在提高气化压力、降低地质安全风险方面优势明显,科学预测气化腔安全宽度对保障气化稳定运行十分重要,由于目前基于可控注入点后退(CRIP)工艺的气化腔安全宽度计算方法尚未建立,为保证现场试验顺利实施,需要开展针对性研究。气化腔顶板“裸露”在气化腔后会受到高温影响,通过数值模拟方法研究了压应力约束条件下岩石内部热应力产生位置以及颗粒、基质热膨胀系数差异对热应力大小的影响规律,结合高温处理后的岩石电镜扫描结果,查明了高温下岩石热损伤机理。根据CRIP气化工艺造腔特点,建立了考虑高温影响的气化腔顶板薄板模型,结合“关键层”理论提出了气化腔安全宽度计算方法。研究表明:岩石热损伤是岩石物理化学反应与热应力互相促进、共同作用的结果,高温下岩石发生不规则变形,岩石热损伤引起的微观结构变化是导致岩石力学性质、物理性质变化的根本原因。岩石的最大拉张热应力出现在颗粒界面或热膨胀系数较小的颗粒中,颗粒与基质热膨胀系数比值在[0.01~1)时,最大拉张热应力随颗粒热膨胀系数减小而快速增加。泥岩加热到200℃时开始出现微裂隙;加热到400℃时裂隙发育更加明显,主要是沿颗粒边缘破裂;加热到600~800℃时,裂隙数量增多、尺寸变大;加热到1000℃时,除出现较大裂隙外,还产生了大量孔隙;1200℃时裂隙连通性明显增加,气孔发育较大。由于高温的影响,薄板模型的步距准数不再是定值,需要根据气化腔顶板热破坏范围与顶板硬岩层的空间位置关系确定具体数值。气化腔安全宽度受温度影响,在研究算例中,砂岩顶板在35、1000℃时安全宽度计算结果分别为34.3 m和14.1 m,相差达58.9%,泥岩顶板在35、1000℃时安全宽度计算结果分别为16.7 m和15.9 m,相差4.8%。最后从降低顶板垮落风险、有利于气化控制角度,提出了煤层纵向靶区位置的确定方法,当煤层厚度超过气化腔安全宽度一半时,建议将水平井纵向靶区设计在距离煤顶不超过气化腔安全宽度一半的位置。

关键词：煤炭地下气化可控注入点后退工艺气化腔热应力热损伤薄板模型步距准数安全宽度