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3D GIS与有限元模拟无缝耦合方法及其在隧道工程中的应用研究

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岩土力学 2017年第3期38卷 866-874,901页

作者：刘振平刘建何雨微贺怀建卞康中国科学院武汉岩土力学研究所岩土力学与工程国家重点实验室湖北武汉430071 湖北武穴长江公路大桥有限公司湖北武穴435400

为实现数值模拟获得的各种场数据与GIS空间信息的综合集成,有必要对GIS中融合有限元数值计算的方法开展研究。本文采用GRASS GIS、VTK等开源软件,通过Python语言建立了GIS与有限元模拟的复合系统开发框架,针对隧道开挖编写了3DGIS与有... 详细信息

为实现数值模拟获得的各种场数据与GIS空间信息的综合集成,有必要对GIS中融合有限元数值计算的方法开展研究。本文采用GRASS GIS、VTK等开源软件,通过Python语言建立了GIS与有限元模拟的复合系统开发框架,针对隧道开挖编写了3DGIS与有限元数值计算无缝耦合分析程序(3DPyGisTFEM)。给出了由中心线上多条轮廓线生成隧道模型的算法,提出了对各地层DEM与隧道模型进行剖切运算获得隧道开挖地质剖面的方法。引入Delaunay网格剖分算法,对GIS中TIN模型不断改良,获得了适合有限元模拟的地质剖面三角形网格。基于多个剖面计算结果,运用插值手段,形成研究区域场数据,结合GIS空间分析方法,对场数据分布规律进行综合分析,实现了GIS与有限元的无缝耦合。黄家寨隧道工程实例表明,相对坡度、隧道中心线缓冲区等因素,地表距隧道拱顶高差的空间分布特征与地表沉降规律相关性更强。

关键词：有限元法地理信息系统 Delaunay网格剖分算法无缝耦合隧道工程

Experimental and numerical simulation of the attenuation effect of blast shock waves in tunnels at different altitudes

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Defence Technology(防务技术) 2025年第1期43卷 120-141页

作者： Changjiang Liu Hujun Li zhen Wang Yong he Guokai Zhang Mingyang Wang School of Mechanical Engineering Nanjing University of Science and TechnologyNanjing 210094China State Key Laboratory of Disaster Prevention and Mitigation of Explosion and Impact People's Liberation Army Engineering UniversityNanjing 210014China

Traffic engineering such as tunnels in various altitudinal gradient zone are at risk of accidental explosion,which can damage personnel and *** prediction of the distribution pattern of explosive loads and shock wave propagation process in semi-enclosed structures at various altitude environment is key research focus in the fields of explosion shock and fluid *** effect of altitude on the propagation of shock waves in tunnels was investigated by conducting explosion test and numerical *** on the experimental and numerical simulation results,a prediction model for the attenuation of the peak overpressure of tunnel shock waves at different altitudes was *** results showed that the peak overpressure decreased at the same measurement points in the tunnel entrance under the high altitude *** contrast,an increase in altitude accelerated the propagation speed of the shock wave in the *** average error between the peak shock wave overpressure obtained using the overpressure prediction formula and the measured test data was less than15%,the average error between the propagation velocity of shock waves predicted values and the test data is less than 10%.The method can effectively predict the overpressure attenuation of blast wave in tunnel at various altitudes.

关键词： Shock wave propagation Tunnel Altitude effect Peak overpressure Shock waves velocity Engineering safety

Risk assessment and genomic characterization of Zika virus in China and its surrounding areas

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Chinese Medical Journal 2019年第14期132卷 1645-1653页

作者： Rong-Fei Liu zhen-jian he Peng Mei Jia-Cheng Xi Xu-Dong Cao Li-Hong Yuan Jia-Hai Lu School of Public health Sun Yat-sen UniversityGuangzhouGuangdong 510080China Key Laboratory of Tropical Disease Control(Sun Yat-sen University) Ministry of EducationGuangzhouGuangdong 510080China Department of Chemical and Biological Engineering University of OttawaOttawaOntarioCanada School of Life Sciences and Biopharmaceutics Guangdong Pharmaceutical UniversityGuangzhouGuangdong 510006China One health Center of Excellence for Research & Training Sun Yat-sen UniversityGuangzhouGuangdong 510080China

Background:Zika virus (ZIKV) has emerged as a global pathogen causing significant public health *** has reported several imported cases where ZIKV were carried by travelers who frequently travel between China and ZIKV-endemic *** fully characterize the ZIKV strains isolated from the cases reported in China and assess the risk of ZIKV transmission in China,comprehensive phylogenetic and genetic analyses were performed both on all ZIKV sequences of China and on a group of scientifically selected ZIKV sequences reported in some of the top interested destinations for Chinese ***:ZIKV genomic sequences were retrieved from the National Center for Biotechnology Information database through stratified *** event detection,maximum likelihood (ML) phylogenetic analysis,molecular clock analysis,selection pressure analysis,and amino acid substitution analysis were used to reconstruct the epidemiology and molecular transmission of ***:The present study investigated 18 ZIKV sequences from China and 70 sequences from 16 selected *** events rarely happens in all ZIKV Asian *** genomes were generally undergone episodic positive selection (17 sites),and only one site was under pervasive positive *** ZIKV imported into China were Asian lineage and were assigned into two clusters:Venezuela-origin (cluster A) and Samoa-origin cluster (cluster B) with common ancestor from French *** time of most recent common ancestors of Cluster A dated to approximately 2013/11 (95% highest posterior density [HPD] 2013/06,2014/ 03) and cluster B dated to 2014/08 (95% HPD 2014/02,2015/01).Cluster B is more variable than Cluster A in comparison with other clusters,but no varied site of biological significance was *** strains in Southeast Asia countries are independent from strains in America ***:The genetic evolution of ZIKV is *** are two independent intro

关键词： Zika virus China Phylogeny Genetic evolution Risk assessment

Failure mechanisms of AlGaN/GaN heMTs irradiated by high-energy heavy ions with and without bias

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Nuclear Science and Techniques 2025年第1期36卷 49-58页

作者： Pei-Pei Hu Li-Jun Xu Sheng-Xia Zhang Peng-Fei Zhai Ling Lv Xiao-Yu Yan Zong-zhen Li Yan-Rong Cao Xue-Feng zheng jian Zeng Yuan he Jie Liu Institute of Modern Physics Chinese Academy of Sciences(CAS)Lanzhou 730000China Key Laboratory of Wide Band‑gap Semiconductor Materials Ministry of EducationXidian UniversityXi’an 710071China University of Chinese Academy of Sciences(UCAS) Beijing 100049China

Gallium nitride(GaN)-based devices have significant potential for space ***,the mechanisms of radiation damage to the device,particularly from strong ionizing radiation,remains *** study investigates the effects of radiation on p-gate AlGaN/GaN high-electron-mobility transistors(heMTs).Under a high voltage,the heMT leakage current increased sharply and was accompanied by a rapid increase in power density that caused"thermal burnout"of the *** addition,a burnout signature appeared on the surface of the burned devices,proving that a single-event burnout effect ***,degradation,including an increase in the on-resistance and a decrease in the breakdown voltage,was observed in devices irradiated with high-energy heavy ions and without *** latent tracks induced by heavy ions penetrated the heterojunction interface and extended into the GaN ***,a new type of N_(2)bubble defect was discovered inside the tracks using Fresnel *** accumulation of N_(2)bubbles in the heterojunction and buffer layers is more likely to cause leakage and *** study indicates that electrical stress accelerates the failure rate and that improving heat dissipation is an effective reinforcement method for GaN-based devices.

关键词： GaN heMTs heavy ions Single-event burnout Latent tracks Degradation

Positive effect of Mo on mechanical properties of a Ni-42W-10Co-xMo medium heavy alloy

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China Foundry 2025年第1期22卷 108-116页

作者： Guo-xin Cao jian-xin Dong Yong-sheng he he jiang Fang Hao Zhi-hua Nie Teng-fei Ma Bao-quan Fu School of Materials Science and Engineering University of Science and Technology BeijingBeijing 100083China Xi'an Superalloy Technology Co. Ltd.Xi’an 710299China School of Materials Science and Engineering Beijing Institute of TechnologyBeijing 100081China Key Laboratory of Air-driven Equipment Technology of Zhejiang Province Quzhou UniversityQuzhou 324000ZhejiangChina

In this study,a novel Ni-W-Co-Mo medium heavy alloy(MHA)was designed to improve its mechanical strength via Mo *** the Ni-42W-10Co-x Mo alloy series,where x represents the weight percent of Mo and varies between 0,1,2,5,and 10,the microstructure transitions from a dendritic structure to a hypo-eutectic structure as the Mo content increases from 0 to 5wt.%.Moreover,as the Mo content increases from 0 to 10wt.%,the distribution of theμ-phase shifts from being individually dispersed to forming aggregates,and its volume fraction rises from 0.5%to 7.9%.Notably,theμ-phase evolves into an eutectic microstructure,which helps in minimizing the segregation of *** change is accompanied by a substantial enhancement in mechanical properties;specifically,the compressive yield strength at room temperature increases from 350 MPa to 646 MPa,indicating a significant 85%***,the microhardness increases from 230 HV to 304 *** dynamics simulations further reveal that the strengthening mechanism of Ni-42W-10Co-x Mo alloys is Mo-induced solid solution strengthening and precipitation strengthening.

关键词： medium-heavy alloys Ni-based alloy mechanical properties solid solution strengthening precipitation strengthening

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Edge supercurrent in Josephson junctions based on topological materials

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Science China(Physics,Mechanics & Astronomy) 2025年第2期68卷 1-12页

作者： Junjie Qi Chui-zhen Chen Juntao Song Jie Liu Ke he Qing-Feng Sun X.C.Xie Beijing Academy of Quantum Information Sciences Beijing 100193China School of Physical Science and Technology Soochow UniversitySuzhou 215006China Institute for Advanced Study Soochow UniversitySuzhou 215006China College of Physics and hebei Advanced Thin Films Laboratory Hebei Normal UniversityShijiazhuang 050024China School of Physics Xi’an Jiaotong UniversityMinistry of Education Key Laboratory for Non-Equilibrium Synthesis and Modulation of Condensed MatterXi’an 710049China State Key Laboratory of Low Dimensional Quantum Physics Department of PhysicsTsinghua UniversityBeijing 100084China Frontier Science Center for Quantum Information Beijing 100084China hefei National Laboratory Hefei 230088China International Center for Quantum Materials School of PhysicsPeking UniversityBeijing 100871China Interdisciplinary Center for Theoretical Physics and Information Sciences Fudan UniversityShanghai 200433China

The interplay between novel topological states and superconductivity has garnered substantial interest due to its potential for topological quantum *** Josephson effect serves as a useful probe for edge superconductivity in these hybrid topological *** Josephson junctions based on topological materials,supercurrents exhibit unique quantum interference patterns,including the conventional Fraunhofer oscillations,theΦ_(0)-periodic oscillation,and the 2Φ_(0)-periodic oscillation in response to the external magnetic field(Φ_(0)=h/2e is the flux quantum,h the Planck constant,and e the electron charge).These interference patterns stem from varied Andreev reflection mechanisms and the associated current density *** review seeks to comprehensively examine the theoretical and experimental advancements in understanding the quantum interference patterns of edge supercurrents in Josephson junctions based on quantum spin Hall,quantum Hall,and quantum anomalous Hall systems.

关键词： quantum Hall effect quantum spin Hall effect quantum anomalous Hall effect Josephson junction edge supercurrent Andreev reflection

Insight into the activation of peroxymonosulfate by N-doped copper-based carbon for efficient degradation of organic pollutants:Synergy of nonradicals

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Chinese Chemical Letters 2025年第1期36卷 513-520页

作者： Mengmeng Ao jian Wei Chuan-Shu he heng Zhang Zhaokun Xiong Yonghui Song Bo Lai College of Environmental Sciences Liaoning UniversityShenyang 110036China State Key Laboratory of Hydraulics and Mountain River Engineering College of Architecture and EnvironmentSichuan UniversityChengdu 610065China State Key Laboratory of Environmental Criteria and Risk Assessment Chinese Research Academy of Environmental SciencesBeijing 100012China

The contamination of water resources by phenolic compounds(PCs)presents a significant environmental hazard,necessitating the development of novel materials and methodologies for effective *** this study,a metallic copper-doped zeolitic imidazolate framework was pyrolyzed and designated as CuNC-20 for the activation of peroxymonosulfate(PMS)to degrade phenol(PE).Cu-NC-20 could effectively address the issue of metal agglomeration while simultaneously diminishing copper dissolution during the activation of PMS *** Cu-NC-20 catalyst exhibited a rapid degradation rate for PE across a broad pH range(3-9)and demonstrated high tolerance towards coexisting *** to scavenger experiments and electron paramagnetic resonance analysis,singlet oxygen(^(1)O_(2))and high-valent copperoxo(Cu(Ⅲ))were the predominant reactive oxygen species,indicating that the system was nonradicaldominated during the degradation *** quantitative structure-activity relationship(QSAR)between the oxidation rate constants of various substituted phenols and Hammett constants was *** indicated that the Cu-NC-20/PMS system had the optimal oxidation rate constant withσ^(-)correlation and exhibited a typical electrophilic reaction *** study provides a comprehensive understanding of the heterogeneous activation process for the selective removal of phenolic compounds.

关键词： N-doped copper-based carbon Phenolic compounds Peroxymonosulfate Nonradical pathway Quantitative structure-activity relationship(QSAR)

Characteristic changes in astrocyte properties during astrocyte-to-neuron conversion induced by NeuroD1/Ascl1/Dlx2

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Neural Regeneration Research 2025年第6期20卷 1801-1815页

作者： Qing he zhen Wang Yuchen Wang Mengjie Zhu Zhile Liang Kanghong Zhang Yuge Xu Gong Chen GHM Institute of CNS Regeneration Jinan UniversityGuangzhouGuangdong ProvinceChina

Direct in vivo conversion of astrocytes into functional new neurons induced by neural transcription factors has been recognized as a potential new therapeutic intervention for neural injury and degenerative disorders. However, a few recent studies have claimed that neural transcription factors cannot convert astrocytes into neurons, attributing the converted neurons to pre-existing neurons mis-expressing transgenes. In this study, we overexpressed three distinct neural transcription factors––NeuroD1, Ascl1, and Dlx2––in reactive astrocytes in mouse cortices subjected to stab injury, resulting in a series of significant changes in astrocyte properties. Initially, the three neural transcription factors were exclusively expressed in the nuclei of astrocytes. Over time, however, these astrocytes gradually adopted neuronal morphology, and the neural transcription factors was gradually observed in the nuclei of neuron-like cells instead of astrocytes. Furthermore,we noted that transcription factor-infected astrocytes showed a progressive decrease in the expression of astrocytic markers AQP4(astrocyte endfeet signal), CX43(gap junction signal), and S100β. Importantly, none of these changes could be attributed to transgene leakage into preexisting neurons. Therefore, our findings suggest that neural transcription factors such as NeuroD1, Ascl1, and Dlx2 can effectively convert reactive astrocytes into neurons in the adult mammalian brain.

关键词： aquaporin-4 Ascl1 astrocyte cortex Dlx2 gap junction glia-to-neuron conversion neural regeneration NeuroD1 reprogramming

New Potential Barite Reference Materials for LA-MC-ICP-MS Sulfur Isotope Analysis with Application to Hydrothermal Barite in the Huayangchuan Deposit,Western China

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Journal of Earth Science 2025年第1期36卷 1-10页

作者： Jiali Fu Xinqian he Zhaochu Hu Shuo Yin jian Ma Kaiyun Chen Wen Zhang National Key Laboratory of Uranium Resource Exploration-Mining andNuclear Remote Sensing East China UniversityofTechnologyNanchang 330013China State Key Laboratory of Nuclear Resources and Environment East China University of TechnologyNanchang 330013China School of Earth Sciences East China University of TechnologyNanchang 330013China State Key Laboratory of Geological Processes and Mineral Resources China University of GeosciencesWuhan 430078China State Key Laboratory of Continental Dynamics Department of GeologyNorthwest UniversityXi'an 710069China

Sulfur isotopes of S-bearing materials are powerful tools to trace various geological processes and sulfur sources in earth sciences,especially in ore deposits where sulfide-sulfate pair coprecipitates ***,in-situ S isotope determination of barite is challenging without natural matrix-matched reference *** this study,we present two natural barite reference materials(1-YS and 294-YS)for in-situ sulfur isotopic *** LA-MC-ICP-MS laboratories were utilized to test theδ34S micron-scale homogeneity of 1-YS and 294-YS barites that have 2s repeatabilities of better than±0.45‰and±0.41‰,***,the in-situ analysis results are consistent with the results of the bulk analysis by GS-IRMS within *** grand meanδ~(34)S values of 1-YS(13.37‰±0.42‰,2s)and 294-YS(14.38‰±0.44‰,2s)are the final recommended values obtained from four independent *** the results confirm the suitability of 1-YS and 294-YS barite used as calibration materials with respect to in-situ S isotopic ***,the new developed barite reference materials were used as matrix-matched standard to calibrate the barite samples from the Huayangchuan carbonatite-hosted U-polymetallic deposit(Qinling orogenic belt,western China)to obtainδ34S *** the temperaturedependentδ34S fractionation of barite-pyrite pair,we calculate the formation temperature of barite(i.e.,506 to 537°C)and theδ34S value of mineralizing fluid(i.e.,-7.11‰to-7.59‰)in the Huayangchuan *** results indicate an involvement of sedimentary sulfur,presumably acting as a potential uranium source(e.g.,upper crustal materials)for the giant Huayangchuan deposit.

关键词： LA-MC-ICP-MS S isotope reference material barite geothermometry