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不导水断层构造的二维瞬变电磁响应特征研究

中国矿业 2024年第1期33卷 122-129页

作者：乔元栋杨振强焦俊俊牛兴国兰永青谭丁瑞山西大同大学建筑与测绘工程学院山西大同037003 内蒙古农业大学能源与交通工程学院内蒙古呼和浩特010018 中国矿业大学(北京)地球科学与测绘工程学院北京100083 内蒙古自治区有色地质勘查局内蒙古呼和浩特010010 山东正元地球物理信息技术有限公司山东济南250101

采煤面前方隐伏不导水断层是煤矿开采现场的潜在事故隐患,需要对其展开细致研究。首先,引入了二维瞬变电磁正演计算公式,并采用有限单元数值计算方法进行了求解,数值计算结果与解析解的结果较吻合。其次,建立含断层构造和不含断层构造... 详细信息

采煤面前方隐伏不导水断层是煤矿开采现场的潜在事故隐患,需要对其展开细致研究。首先,引入了二维瞬变电磁正演计算公式,并采用有限单元数值计算方法进行了求解,数值计算结果与解析解的结果较吻合。其次,建立含断层构造和不含断层构造的二维地质模型,并对模型进行数值计算。研究结果表明:感应磁场等值线对高阻断层构造的响应规律明显,等值线畸变的形状和范围与模型中断层的位置、走向和倾角吻合度较好。随着测点位置与断层的距离减小,感应电动势响应幅值在采样早期呈增大趋势,但尖点响应的最小幅值逐渐变大,有断层模型的尖点响应下凹的幅度相较无断层模型更大。视电阻率成像结果能较好地反映高阻断层与煤系地层的电性特征,表明正演结果准确可靠。

关键词：瞬变电磁法断层有限单元法数值模拟正演

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基于概率模型辅助的高压断路器故障预测研究

电气传动自动化 2024年第3期46卷 41-44,53页

作者：刘霞冯海荣杨震强刘伟许永锋焦毛国网陕西省电力有限公司延安供电公司陕西延安716000

概率模型可用于辅助研究高压开关柜断路器的故障预测,并可基于历史故障数据和其他相关因素,通过统计分析和机器学习算法来预测高压开关柜断路器的故障概率。高压开关柜断路器(HVSCB)中大多数故障的根源是运行机制,而行程曲线(TC)可以有... 详细信息

概率模型可用于辅助研究高压开关柜断路器的故障预测,并可基于历史故障数据和其他相关因素,通过统计分析和机器学习算法来预测高压开关柜断路器的故障概率。高压开关柜断路器(HVSCB)中大多数故障的根源是运行机制,而行程曲线(TC)可以有效地揭示操作机构的状态。本文介绍了HVSCB常见失效模式对TC剖面的影响,并提出了一种新的模型辅助方法,将基于模型的方法和基于规则的方法相结合来模拟操作机构的行为。HVSCB的工况根据其运行速度分为三种模式即正常(约3 m/s)、故障1(小于正常范围)和故障2(大于正常范围)。HVSCB的模式变化已通过交互式多模型(IMM)在每次操作中进行了估计,所提出预测故障和分析故障原因的方法已通过了实验验证。

关键词：高压开关柜断路器状态监测概率模型辅助行程曲线

Local failure mechanism of sand-blocking fence in latticed dune along desert roads

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Journal of Mountain Science 2024年第2期21卷 526-537页

作者： LI Liangying LV Lele LI Qi WANG zhenqiang yang Youhai YIN Wenhua School of Civil Engineering Lanzhou Jiaotong UniversityLanzhou 730070China Ningxia Highway Survey and Design Institute Co Ltd Yinchuan 750001China

The latticed dunes in the Tengger Desert are widely distributed,and the sand-blocking fence placed here are highly susceptible to local failure due to complex wind-sand activities,posing a serious threat to the safe operation of the *** explore the local failure mechanism of sand-blocking fence in the latticed dune area,the local failure of sand-blocking fence in the latticed dune areas along the Wuhai-Maqin Highway in China was *** the first main ridge of the latticed dune as the placement location,the structure of the wind-sand flow field of sand-blocking fence placed at top,the bottom and the middle of windward slope was analyzed by Computational Fluid Dynamics(CFD).The results show that when placed at top of the first main ridge,the wind speed near the sand-blocking fence is the highest,up to 15.23 m/***,the wind load strength on the sand barrier is correspondingly larger,up to 232.61 N∙*** the strength of material continues to decrease,the nylon net is prone to *** roots of the angle steel posts are susceptible to hollowing by vortex action,which can cause sand-blocking fence to fall over in strong wind *** placed at the bottom of windward slope,wind speed drop near sand-blocking fence is greatest,with the decrease of 12.48-14.32 m/s compared to the original wind *** is highly likely to lead to large-scale deposition of sand particles and burial of the sand-blocking *** placed in the middle of windward slope,sand-blocking fence is subjected to less wind load strength(168.61N∙m-2)and sand particles are mostly deposited at the bottom of windward slope,with only a small amount of sand accumulating at the root of sand-blocking *** on field observations and numerical modelling results,when the sand-blocking fence is placed in latticed dune area,it should be placed in the middle of the windward slope of the first main ridge as a matter of *** the sand-blocking fence should be placed

关键词： Latticed dune Sand-blocking fence Local failure Numerical simulation Desert roads

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一种3-溴芴酮的合成工艺

化工技术与开发 2024年第10期53卷 11-13,22页

作者：韩蒙蒙马欣李瑞陈鹏丽李奎杨振强申奥河南省科学院化学研究所有限公司河南郑州450002 河南科化环境材料有限公司河南沁阳454550

3-溴芴酮是制备有机电致发光材料、太阳能电池材料等功能性材料的重要中间体。本文以2-氨基芴为起始原料,经溴代反应、重氮化反应和氧化反应合成了3-溴芴酮产物。针对氧化过程中溶剂及碱的种类对收率的影响进行了优化选择。较佳的反应... 详细信息

3-溴芴酮是制备有机电致发光材料、太阳能电池材料等功能性材料的重要中间体。本文以2-氨基芴为起始原料,经溴代反应、重氮化反应和氧化反应合成了3-溴芴酮产物。针对氧化过程中溶剂及碱的种类对收率的影响进行了优化选择。较佳的反应条件是:以四氢呋喃作为溶剂,氢氧化钾作为碱时,3-溴芴酮的收率较高,纯度达到99.9%,产品的质量好,生产成本较低,适合工业化生产。

关键词： 2-氨基芴 3-溴芴酮合成工艺

Dual-additives enable stable electrode-electrolyte interfaces for long life Li-SPAN batteries

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Chinese Chemical Letters 2024年第5期35卷 459-465页

作者： zhenqiang Guo Huicong yang Qian Wei Shengjun Xu Guangjian Hu Shuo Bai Feng Li School of Materials Science and Engineering University of Science and Technology of ChinaShenyang 110016China Shenyang National Laboratory for Materials Science Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China Department of Biochemistry and Molecular Biology College of Life ScienceChina Medical UniversityShenyang 110122China Dalian National Laboratory for Clean Energy Dalian 116023China Shenyang King Power Technology Co. Ltd.Shenyang 110016China

Sulfurized polyacrylonitrile(SPAN)is proposed as a promising cathode material for lithium sulfur ***,the continuous side reactions at the electrolyte-electrode interfaces as well as the slow redox kinetics of SPAN cathode deteriorate the electrochemical *** this study,an electrolyte with dual-additives comprising 2-fluoropyridine(2-FP)and lithium difluorobis(oxalato)phosphate(LiDFBOP)was used to improve the performance of Li||SPAN cells.2-FP has a lower lowest occupied molecular orbital energy than that of the solvents in the electrolyte,leading to its prior reduction.A LiF-rich film can be formed on the electrode,effectively improving the stability of the electrolyte-electrode interfaces and prolonging the ***,LiDFBOP could form an electrolyte-electrode interface film containing a large amount of Li_(x)PO_(y)F_(z) species,compensating for the kinetic deterioration caused by the lower ionic conductive of LiF formed at the electrolyte-electrode ***,an electrode-interface film with good chemical stability and high Li^(+) transport was established by LiF and Li_(x)PO_(y)F_(z)-rich *** Li||SPAN cell with the electrolyte containing dual-additives demonstrates an excellent capacity retention of 97.5%after 200 cycles at 1.0 C,25℃,comparing to 56.2%capacity retention without ***,the rate capacities of cells with dual-additives can reach 1128.1 mAh/g at 5 C,comparing to only 813.5 mAh/g using electrolyte without *** results shown that the dual-additives in electrolyte provide a promising strategy for practical application of lithium sulfur batteries with SPAN cathodes.

关键词： Sulfurized polyacrylonitrile Lithium metal Interface film 2-Fluoropyridine Difluorobis(oxalato)phosphate

Establishment of a three-dimensional particle library for graded crushed stone based on a new aggregate morphology characterization method

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Journal of Traffic and Transportation Engineering(English Edition) 2024年第1期11卷 117-130页

作者： Haitao Ge Aimin Sha zhenqiang Han School of Future Transportation Chang'an UniversityXi'an 710064China University of Strasbourg INSA StrasbourgCNRSICubeUMR 7357Strasbourg F-67000France School of Highway Chang'an UniversityXi'an 710064China Key Laboratory for Special Area Highway Engineering of Ministry of Education Chang'an UniversityXi'an 710064China

The morphology of graded crushed stone(GCS)particles has an essential influence on the performance of aggregate *** impact of particle shape is a comprehensive effect that cannot be considered separately,leading to difficulties in establishing the relationship between the mixture properties and the aggregate morphology by using laboratory *** discrete element method(DEM)is an effective way widely adopted to reconstruct the morphology of particles and simulate performance tests of granular ***,selecting limited particles characterizing a real particle-assembly for simulation is still a challenge in current research due to the inherent rich variability of particle *** this study,based on the acquisition of three-dimensional(3D)aggregate shapes by using laser scanning,ellipsoid index(EDI)translating the particle shape as a function of surface area,volume,and contour length is proposed to comprehensively evaluate aggregate ***,a particle library capable of characterizing aggregate morphology distribution is established based on the statistics of the corresponding morphological characteristics of particle *** model reliability is validated by carrying out a series of experimental and numerical penetration tests with nine different *** established particle library can be used to model aggregate mixtures and the proposed simulation framework is promising for optimizing the mixture gradation design numerically.

关键词： Particle library Discrete element method 3D laser scanning Coarse aggregate Morphology characterization Gradation design

Effects of extracellular vesicle-derived noncoding RNAs on pre-metastatic niche and tumor progression

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Genes & Diseases 2024年第1期11卷 176-188页

作者： Zhuang Chen Qiming Wang Jinbo Liu Wenkang Wang Weitang Yuan yang Liu zhenqiang Sun Chengzeng Wang Department of Colorectal Surgery The First Affiliated Hospital of Zhengzhou UniversityZhengzhouHenan 450052China Academy of Medical Sciences of Zhengzhou University ZhengzhouHenan 450001China Department of Internal Medicine Affiliated Cancer Hospital of Zhengzhou UniversityHenan Cancer HospitalZhengzhouHenan 450008China Department of Breast Surgery The First Affliated Hospital of Zhengzhou UniversityZhengzhouHenan 450052China Department of Radiotherapy Affiliated Cancer Hospital of Zhengzhou UniversityHenan Cancer HospitalZhengzhouHenan 450008China The First Affiliated Hospital of Zhengzhou University ZhengzhouHenan 450052China

A pre-metastatic niche(PMN)is a protective microenvironment that facilitates the colonization of disseminating tumor cells in future metastatic *** vesicles(EVs)play a role in intercellular communication by delivering cargoes,such as noncoding RNAs(ncRNAs).The pivotal role of extracellular vesicle-derived noncoding RNAs(EV-ncRNAs)in the PMN has attracted increasing *** this review,we summarized the effects of EV-ncRNAs on the PMN in terms of immunosuppression,vascular permeability and angiogenesis,inflammation,metabolic reprogramming,and fibroblast *** particular,we provided a comprehensive overview of the effects of EV-ncRNAs on the PMN in different ***,we discussed the promising clinical applications of EV-ncRNAs,including their potential as diagnostic and prognostic markers and therapeutic targets.

关键词： Biomarker Extracellular vesicles Noncoding RNAs

Microbiome in Female Reproductive Health:Implications for Fertility and Assisted Reproductive Technologies

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Genomics, Proteomics & Bioinformatics 2024年第1期22卷 5-18页

作者： Liwen Xiao zhenqiang Zuo Fangqing Zhao CAS Key Laboratory of Systems Biology Hangzhou Institute for Advanced StudyUniversity of Chinese Academy of SciencesHangzhou 310024China Beijing Institutes of Life Science/Institute of Zoology Chinese Academy of SciencesBeijing 100101China University of Chinese Academy of Sciences Beijing 100049China

The microbiome plays a critical role in the process of conception and the outcomes of *** in microbiome homeostasis in women of reproductive age can lead to various pregnancy complications,which significantly impact maternal and fetal *** studies have associated the microbiome in the female reproductive tract(FRT)with assisted reproductive technology(ART)outcomes,and restoring microbiome balance has been shown to improve fertility in infertile *** review provides an overview of the role of the microbiome in female reproductive health,including its implications for pregnancy outcomes and ***,recent advances in the use of microbial biomarkers as indicators of pregnancy disorders are summarized.A comprehensive understanding of the characteristics of the microbiome before and during pregnancy and its impact on reproductive health will greatly promote maternal and fetal *** knowledge can also contribute to the development of ARTs and microbiome-based interventions.

关键词： Microbiome Pregnancy Female reproductive health Assisted reproductive technology Microbial biomarker

Jet Characteristics and Optimization of a Cavitation Nozzle for Hydraulic Fracturing Applications

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Fluid Dynamics & Materials Processing 2024年第1期20卷 179-192页

作者： Yu Gao zhenqiang Xu Kaixiang Shen Shenzhen South China Sea Oil Economic Development Co. Ltd.Shenzhen518000China Guangzhou Marine Geological Survey China Geological SurveyGuangzhou511458China National Engineering Research Center of Gas Hydrate Exploration and Development Guangzhou511458China

Hydraulic jetting is a form of fracturing that involves using a high-pressure jet of water to create fractures in the reservoir rock with a nozzle serving as the central component of the hydraulic sandblasting perforation *** this study,the flow behavior of the nozzle is simulated numerically in the framework of a SST k-ωturbulence *** results show that the nozzle structure can significantly influence the jet performance and related cavitation *** orthogonal experiments,the nozzle geometric parameters are optimized,and the following configuration is found accordingly:contraction angle 20°,contraction segment length 6 mm,cylindrical segment diameter 6 mm,cylindrical segment length 12 mm,spread segment length 10 mm,and spread angle 55°.

关键词： Cavitation jet angle nozzle hydraulic characteristics nozzle parameters