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Dynamic process analysis of the Niumiangou landslide triggered by the Wenchuan earthquake using the finite difference method and a modified discontinuous deformation analysis

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Journal of Mountain Science 2021年第4期18卷 1034-1048页

作者： HUANG Da meng qiu-jie SONG Yi-xiang CUI Sheng-hua CEN Duo-feng School of Civil and Transportation Engineering Hebei University of TechnologyTianjin 300401China State Key Laboratory of Geohazard Prevention and Geoenvironment Protection Chengdu University of TechnologyChengdu 610059China

The Niumiangou landslide was the largest landslide triggered by the 2008 Wenchuan earthquake,which was significantly affected by the amplification effect of seismic *** ringshear experiments indicated that the materials in the source area of the Niumiangou landslide were subjected to friction degradation under a big shear displacement,which may result in rapid movement of the *** order to better understand the landslide movement and study the effect of the friction degradation on movement mechanisms,the dynamic process of Niumiangou landslide was simulated with a new numerical method,which combines the finite difference method(FDM)and the discontinuous deformation analysis(DDA).First,the FDM was used to study the initiation time,amplification effect and velocity of the ***,these initiation velocities were applied to the blocks in the DDA model by corresponding coordination in the FDM model.A displacementdependent friction model of the sliding surface was incorporated into DDA code to further understand the kinetic behavior of the *** results show that the displacement-dependent friction strongly decreases the friction coefficient of sliding surface under a big displacement,which can obviously promote the run-out and velocity of *** model output well matches the topographic map formed by the *** implies that the proposed model can be applied to the simulation of earthquake-induced landslides with amplification effect,and the friction degradation model is important to clarify the movement mechanism of high-speed and long-distance landslides.

关键词： Wenchuan earthquake Discontinuous deformation analysis(DDA) Niumiangou landslide Amplification effects Displacement-dependent friction model

Effect of seepage-induced erosion on soil macropore structure

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Journal of Mountain Science 2023年第11期20卷 3402-3422页

作者： HUANG Wen-bo HUANG Da GAO Yi-kang LIU Yang LI Zhao meng qiu-jie School of Civil and Transportation Engineering Hebei University of TechnologyTianjin 300401China. College of Geology Engineering and Geomatics Chang’an UniversityXi’an 710054China.

Internal erosion is one of the important factors causing geological *** microstructure of soil can change with seepage erosion,resulting in changes in the hydraulic and mechanical properties of the *** evolution of seepage erosion is investigated with X-ray computed tomography(CT)in this *** change in macropore structure characteristics during the seepage erosion test is quantified and the influence of seepage erosion on soil deformation is ***,a pore network model(PNM)is established for the specimens and the evolution of the connected pore size characteristics is *** results show that the macropore structure is significantly affected by seepage erosion,especially in terms of the porosity and pore geometry *** changes in macropore structure characteristics are most obvious in the lower part of the *** influence of seepage erosion on the pore size distribution(PSD)and soil deformation is heterogeneous and closely dependent on the spatial location of the ***,seepage erosion enhances macropore connectivity and has a directional impact on macropore *** findings can provide a reference for the theoretical modeling and numerical simulation of the seepage erosion and improve the understanding of the seepage erosion evolution in engineering practice.

关键词： Seepage erosion Heterogeneity Macropore structure Pore size distribution Microstructure CT scanning

软硬互层岩质反倾边坡弯曲倾倒离心模型试验与数值模拟研究

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岩土工程学报 2020年第7期42卷 1286-1295页

作者：黄达马昊孟秋杰宋宜祥长安大学地质工程与测绘学院陕西西安710054 重庆大学土木工程学院重庆400044 河北工业大学土木与交通学院天津300401

西部山区工程建设揭露了众多大型弯曲倾倒变形体,多具有软硬互层结构,水平深度可达300 m。为进一步探明软硬互层反倾边坡的倾倒变形机制,融合离心模型试验与UDEC模拟,研究了此类边坡的破坏模式与影响因素,并通过点对分析,讨论了变形的... 详细信息

西部山区工程建设揭露了众多大型弯曲倾倒变形体,多具有软硬互层结构,水平深度可达300 m。为进一步探明软硬互层反倾边坡的倾倒变形机制,融合离心模型试验与UDEC模拟,研究了此类边坡的破坏模式与影响因素,并通过点对分析,讨论了变形的力学机制。数值模拟时,在岩层内预置随机裂隙,获得了破裂面的演化规律。结果表明:数值模拟与试验的位移曲线及破裂面形态吻合较好,边坡变形可分为起始蠕变阶段、稳态变形阶段和失稳破坏阶段;坡体前部为压剪复合变形,后部则以拉张为主;边坡主破裂面呈弧形,由坡脚快速贯通至坡顶,整体为拉–剪性破裂面;坡体内发育3条破裂面,可作为分界线将变形体分为极强倾倒区、强倾倒区和弱倾倒区;坡脚岩体变形后期压致拉裂,逐渐折断脱离母岩,最终导致变形岩体沿不同的破裂面形成渐进后退式破坏;边坡在倾角与坡角之和大于等于120°时才较易破坏,坡角主要影响破坏难易,倾角则控制变形规模。

关键词：反倾边坡软硬互层倾倒变形离心模型试验离散元数值模拟

一种基于对角载入的鲁棒MVDR波束形成算法

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湖南大学学报（自然科学版） 2012年第9期39卷 57-61页

作者：施荣华孟秋杰董健郭迎中南大学信息科学与工程学院湖南长沙410083

当信号方向向量精确已知时,传统最小方差无畸变响应(MVDR)波束形成算法具有较好的分辨率和抗干扰能力.在实际通信环境中,由于外部环境、天线阵列以及采样协方差矩阵的估计误差等因素的影响,导致传统MVDR波束形成算法的性能急剧下降.针... 详细信息

当信号方向向量精确已知时,传统最小方差无畸变响应(MVDR)波束形成算法具有较好的分辨率和抗干扰能力.在实际通信环境中,由于外部环境、天线阵列以及采样协方差矩阵的估计误差等因素的影响,导致传统MVDR波束形成算法的性能急剧下降.针对这一问题,本文提出了一种新的基于对角载入的鲁棒MVDR波束形成算法.该算法考虑信号方向向量的偏差对MVDR算法性能的影响,并在最大允许偏差范围内导出最优的权重向量,有效地抑制了偏差对输出性能的影响,具有很强的鲁棒性,从而能够适应复杂的通信环境;同时该算法采用递推算法避免矩阵求逆,降低了计算复杂度,便于工程实现.仿真实验表明,与传统MVDR算法相比,所提算法具有更好的输出性能。

关键词：波束形成信号方向向量对角载入 MVDR

维普期刊数据库博看期刊

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正融冰川碎屑冰冻体剪切强度劣化机制研究

岩土力学 2024年第1期45卷 197-212页

作者：孟秋杰宋宜祥黄达马文钟助岑夺丰河北工业大学土木与交通学院天津300401 长安大学地质工程与测绘学院陕西西安710064 北京科技大学土木与资源工程学院北京100083

受到气候变暖的影响,青藏高原冰川剪切滑动带中的碎屑冰冻体存在融化风险,这严重影响了冰川的抗剪强度和稳定性。为了研究融化过程对碎屑冰冻体剪切力学特性的影响,引入融冰率定量评估融化程度,对正融碎屑冰冻体试样开展了室内直剪试验... 详细信息

受到气候变暖的影响,青藏高原冰川剪切滑动带中的碎屑冰冻体存在融化风险,这严重影响了冰川的抗剪强度和稳定性。为了研究融化过程对碎屑冰冻体剪切力学特性的影响,引入融冰率定量评估融化程度,对正融碎屑冰冻体试样开展了室内直剪试验。基于试验结果提出了正融碎屑冰冻体的有限-离散元数值模型并进行了对比验证,研究了融冰率和碎石含量对碎屑冰冻体剪切力学行为的影响规律。结果表明:融化过程显著降低了峰值剪切强度、黏聚力和内摩擦角;强度参数与融冰率的关系可用线性准则表达;正碎屑冰冻体剪切强度急剧劣化的主因是孔隙冰融化导致的冻土-孔隙冰界面黏聚力降低;当融冰率从2%增加到4%,试样变形模式由应变软化过渡为应变硬化,破坏模式由粗糙的“锯齿状”过渡为平滑的“圆弧状”;随着碎石含量增加,碎屑冰冻体剪切强度明显降低,降低幅度随融冰率的增加而减小。该研究可作为冰川稳定性评价的有益补充。

关键词：碎屑冰冻体融化直剪试验剪切力学行为有限-离散元

刑事和解工作实证分析——以怀化市鹤城区人民检察院为蓝本

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怀化学院学报 2014年第10期33卷 84-87页

作者：张均邱孟洁怀化市人民检察院怀化市鹤城区人民检察院湖南怀化418000

修改后的刑事诉讼法增设了刑事和解制度,刑事和解作为一种新的结案方式,在构建和谐社会的背景下具有重要意义。在检察工作实践中案件的多元与复杂,使刑事和解面临传统刑事司法理念的影响,存在诉讼风险性、钱刑交易、赔偿不到位、刑事和... 详细信息

修改后的刑事诉讼法增设了刑事和解制度,刑事和解作为一种新的结案方式,在构建和谐社会的背景下具有重要意义。在检察工作实践中案件的多元与复杂,使刑事和解面临传统刑事司法理念的影响,存在诉讼风险性、钱刑交易、赔偿不到位、刑事和解运用范围把握不当、协调环节过多导致和解率偏低等问题,对上述问题进行实证分析,具体考量刑事和解制度的实施与运行,严格规范和解效力,构建多元和解方式,建立和解内外监督体系,加大和解工作宣传力度,有利于刑事和解制度在检察实践中贯彻与践行。

关键词：刑事和解检察实践实证分析对策建议

Surface-confined persistent luminescence with amplified FRET efficiency for cell-cell communication monitoring

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Science China Chemistry 2025年

作者： Ziyun Miao Wenjing Dai Yubin Jin Bing Qi Jiayi Chen Lingling qiu Yurong Wei jie Wang The Key Lab of Health Chemistry&Molecular Diagnosis of Suzhou College of ChemistryChemical Engineering&Materials ScienceSoochow University

Microbial communication monitoring is vital for understanding the mechanisms beneath gut microbiota equilibrium, infections,and biomanufacturing. Herein, we reported monitoring bacterial communication by surface-confined persistent ***, we constructed core-shell structured Zn1.4Ga1.2Ge0.4O4@Zn1.4Ga1.2Ge0.4O4:Cr（ZGGO@ZGGO:Cr） persistent luminescence nanoparticles（PLNPs） with amplified FRET efficiency for the detection of azoreductase（AzoR） that participates in bacterial communication. ZGGO@ZGGO:Cr nanoparticles were functionalized with an azo black hole quencher（ZGGO@ZGGO:Cr-BHQ-3）. Due to the proximity of surface-confined persistent luminescence with the surface-bound BHQ-3,ZGGO@ZGGO:Cr-BHQ-3 exhibited a FRET efficiency up to 1.6 times that of traditional ZGGO:Cr-BHQ-3. Further, the specific catalytic reduction of azo bonds in BHQ-3 by bacterial extracellular AzoR recovers the persistent luminescence of ZGGO@ZGGO:Cr. ZGGO@ZGGO:Cr-BHQ-3 displayed superior sensitivity and speed in detecting extracellular AzoR over ZGGO:Cr-BHQ-3, attributed to its surface-confined persistent luminescence. We found that the peak secretion of AzoR occurs during the exponential growth period of bacteria including S. aureus and E. coli based on the persistent luminescence recovery rate of ZGGO@ZGGO:Cr-BHQ-3. Furthermore, ZGGO@ZGGO:Cr-BHQ-3 was used to probe the communication between different bacterial species. R. palustris is a kind of lycopene-production bacteria. We found that the cohabitation of R. palustris and S. putrefaciens boosted both AzoR secretion and lycopene production. Moreover, the secretion and activity of AzoR positively correlated with lycopene production, suggesting that AzoR may participate in the communication between R. palustris and S. putrefaciens to promote lycopene production. This study offers a robust method to enhance PLNP-based biosensing sensitivity and provides a promising strategy for microbial communication monitoring.

关键词：

超氧化物歧化酶抑制精液来源的病毒增强因子形成的研究

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上海交通大学学报（医学版） 2021年第4期41卷 467-472页

作者：邱梦婕李钊锋黎奕斌陈玉柳程宏彦刘叔文谭穗懿南方医科大学药学院广州510515

目的·探究超氧化物歧化酶(superoxide dismutase,SOD)对精液来源的病毒增强因子(semen-derived enhancer of viral infection,SEVI)淀粉样纤维形成的抑制作用。方法·将440μmol/L的前列腺酸性磷酸酶248-286(prostatic acid phosphatase 248-286,PAP248-286)多肽溶液或精液分别与不同活性水平的SOD混合孵育,于不同的时间点取样,用硫磺素T染色法、圆二色谱法、透射电子显微镜检测SOD对SEVI形成的影响;用病毒感染增强实验,检测SOD对SEVI促进人类免疫缺陷病毒1型(human immunodeficiency virus-1,HIV-1)感染能力的影响。灭活SOD并检测其对SEVI形成及病毒感染能力的影响。总SOD活性检测试剂盒检测5份健康志愿者精液中SOD的活性水平。结果·硫磺素T染色法结果显示,48 h时,46 U/mL和92 U/mL的SOD在体外可以抑制PAP248-286溶液形成SEVI淀粉样纤维;圆二色谱结果表明SOD可以抑制SEVIβ-折叠结构的形成;透射电子显微镜结果也表明,SOD对SEVI的形成具有抑制作用。精液中的硫磺素T染色分析结果显示,SOD可抑制精液中的SEVI形成。病毒感染增强实验结果显示,SOD能够抑制SEVI促进HIV-1感染能力的作用。SOD灭活后上述作用均基本消失。5份健康男性精液中SOD活性分别为74.87、68.69、85.46、113.29、109.53 U/mL。结论·SOD在体外可以抑制SEVI淀粉样纤维的形成及其促进HIV-1感染的作用。

关键词：超氧化物歧化酶精液来源的病毒增强因子淀粉样纤维人类免疫缺陷病毒性传播精液

Optimized Bi-level Control for Day-ahead and Real-time Active Power Balancing of an Off-grid Wind Power-to-hydrogen System With ESS Considering Wind Power Uncertainty

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Dianwang Jishu/Power System Technology 2025年第1期49卷 52-62页

作者： qiu, Yiwei Sun, Qingjie Wu, Chenxu Zhu, jie Zeng, Yangjun Chen, Shi Zhou, Buxiang College of Electrical Engineering Sichuan University Sichuan Province Chengdu 610065 China State Grid Ningbo Power Supply Company Zhejiang Province Ningbo 315012 China

Since off-grid wind power-to-hydrogen (Wp2H) systems are not connected to the utility grid, the hydrogen production load and the energy storage system (ESS) must be coordinated to absorb wind power fluctuations and maintain system stability. Such coordination must consider the flexibility constraints of hydrogen production units, the overall hydrogen yield, and the degradation of batteries in the ESS to meet the economic goals of green hydrogen production. Therefore, an optimized bi-level control method for the active power balance is proposed. Firstly, using the Itô process to characterize wind power fluctuations and considering the real-time flexibility reserve of multiple electrolyzers, the upper level is formulated as an intra-day scheduling problem with a 15-minute resolution. Secondly, the lower level optimizes the real-time power of the electrolyzers and the ESS based on their on-off states and baseline power commanded by the upper level, considering the degradation cost of the ESS. This helps to absorb second-level wind power fluctuations. Finally, based on a project plan in Inner Mongolia, China, a case study verifies the effectiveness of the proposed method. © 2025 Power System Technology Press. All rights reserved.

关键词： Hydrogen storage