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Protective effects of baffles with different positions,row spacings,heights on debris flow impact

Journal of Mountain Science 2024年第7期21卷 2352-2367页

作者： SUN Xinpo cheN Min BI Yuzhang ZHENG Lu che chi XU Ao TIAN Zijian JIANG Zheyuan College of Civil Engineering Sichuan University of Science and EngineeringZigong 643000China College of Resources and Environment Fujian Agriculture and Forestry UniversityFuzhou 350002China School of Civil Engineering Fuzhou UniversityFuzhou 350108China Jiangsu Key Laboratory of Urban Underground Engineering&Environmental Safety Institute of Geotechnical EngineeringSoutheast UniversityNanjing 210096China Beijing Urban Construction Science Technology Promoting Association Beijing 100055China SUSE-BZ Geoenvironmental Engineering Joint Laboratory Sichuan University of Science and EngineeringZigong 643000China

The baffle effectively slowed down debris flow velocity,reduced its kinetic energy,and significantly shortened the distance of debris flow ***,they are widely used for protection against natural hazards such as landslides and *** study,based on the threedimensional DEM(Discrete Element Method),investigated the impact of different baffle positions on debris flow *** flow velocity and kinetic energy variations were studied through single-factor *** baffle positions were preliminarily selected by analyzing the influence of the first-row baffle position on the impact force and accumulation mass of debris ***,based on the selected baffle positions and four factors influencing the effectiveness of baffle protection(baffle position(P),baffle height(h),row spacing(S_(r)),and angle of transit area(α)),an orthogonal design was employed to further explore the optimal arrangement of *** research results indicate that the use of a baffle structure could effectively slow down the motion velocity of debris flows and dissipate their *** the baffle is placed in the transit area,the impact force on the first-row baffle is greater than that when the baffle is placed in the deposition ***,when the baffle is placed in the transit area,the obstruction effect on debris flow mass is also greater than that when the baffle is placed in the deposition *** orthogonal experimental range analysis,when the impact on the first row of baffles is used as the evaluation criterion,the importance of each influencing factor is ranked asα>P>S_(r)>*** the mass of debris flow behind the baffle is regarded as the evaluation criterion,the rank is changed to P>α>S_(r)>*** experimental simulation results show that the optimal baffle arrangement is:P_(5),S_(r)=16,α=35°,h=9.

关键词： Debris flow Baffle Protective effect Discrete element

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射血分数降低型心力衰竭中医证型与BNP、CA125表达水平及心功能的相关性分析

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辽宁中医杂志 2024年第2期51卷 86-90页

作者：车驰田鑫彭双凤王晓琳陈智勇黄婉清李林江西中医药大学江西南昌330006 江西中医药大学附属医院江西南昌330006

目的探讨射血分数降低型心力衰竭(heart failure with reduced ejection fraction,HFrEF)中医证型与脑钠肽(brain natriuretic peptide,BNP)、血清糖类抗原125(CA125)及心功能的相关性。方法对纳入的HFrEF患者进行中医辨证分型,记录各证型患者的心功能分级、左心超声心功能指标、BNP及CA125表达水平,并进行统计分析。结果HFrEF患者不同中医证型之间BNP及CA125差异有统计学意义(P<0.05);不同心功能等级之间BNP差异有统计学意义(P<0.05);BNP、CA125与HFrEF中医证型呈正相关。结论HFrEF患者的中医证型主要分布在阳虚水泛证,BNP及CA125值基本随中医证型气阴两虚证、气虚血瘀证、痰饮阻肺证、阳虚水泛证、心阳虚脱证顺序递增,对于辅助HFrEF的辨证分型有一定参考价值。

关键词：射血分数下降心力衰竭中医证型 CA125 BNP 心功能分级

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Coupling Effects of A Deep-Water Drilling Riser and the Platform and the Discharging Fluid Column in An Emergency Disconnect Scenario

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china Ocean Engineering 2020年第1期34卷 21-29页

作者： MENG Shuai cheN Yong che chi-dong State Key Laboratory of Ocean Engineering Collaborative Innovation Center for Advanced Ship and Deep-sea ExplorationShanghai Jiao Tong UniversityShanghai 200240China Shanghai Marine Diesel Engine Research Institute Shanghai 200240China

As drilling operations move into remote locations and extreme water depths, recoil analysis requires more careful considerations and the incidence of emergency disconnect is increased inevitably. To accurately capture the recoil dynamics of a deep-water riser in an emergency disconnect scenario, researchers typically focus on modelling the influential subsystems (e.g., the tensioner, the mud discharge and seawater refilling process) which can be solved in the preprocessing, and then the determined parameters are transmitted into an existing global riser analysis software. Distinctively, the current study devotes efforts into the coupling effects resulting from that the suspended riser reacts the platform heave motion via the tensioner system in the course of recoil and the discharging fluid column follows the oscillation of the riser in the mud discharge process. Four simulation models are established based on lumped mass method employing different formulas for the top boundary condition of the riser and the discharging flow acceleration. It demonstrates that the coupling effects discussed above can significantly affect the recoil behavior during the transition phase from initial disconnect to the final hang-off state. It is recommended to develop a fully- coupled integrated model for recoil analysis and anti-recoil control system design before extreme deep-water applications.

关键词： recoil analysis emergency disconnect coupling effect platform excitation

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Corrosion assessment for spent nuclear fuel disposal in crystalline rock,using variant cases of hydrogeological modeling

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Nuclear Science and Techniques 2020年第12期31卷 20-31页

作者： chi-che Hung Fraser King Yun-chen Yu chi-Jen chen Yuan-chieh Wu Wei-Ting Lin 机构不详

This paper presents a corrosion assessment of copper spent nuclear fuel disposal canisters in crystalline rock,using hydrogeological modeling.A simplified approach is considered,to avoid complex and time-consuming computer *** simplified case is presented as a base case,with changes in the hydrogeological parameters presented as variant *** results show that in Taiwan’s base case,decreasing the hydraulic conductivity of the rock or decreasing the hydraulic conductivity of dikes results in a shorter transport path for sulfide and an increase in corrosion ***,the estimated canister failure time is still over one million years in the variant cases.

关键词： Spent nuclear fuel disposal Corrosion assessment Hydrogeological modeling

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基于p38-MAPK通路探讨真武汤对心力衰竭心肌细胞结构重构-电重构的影响

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中华中医药学刊 2024年第4期42卷 130-137,I0032-I0034页

作者：王晓琳张倩田鑫陈智勇车驰徐丽丽刘智明陈智军王兴廖金花廖东华李林江西中医药大学研究生院江西南昌330000 修水县第一人民医院江西九江332000 江西中医药大学附属医院江西南昌330000 湖南省直中医医院湖南株洲412000 广州市增城区中医医院广东广州510000

目的真武汤在治疗慢性心力衰竭(Heart Failure,HF)过程中能够改善心律失常,旨在从p38-MAPK通路调控肥大心肌结构重构和电重构角度探讨真武汤治疗HF相关心律失常的作用机制。方法用AngⅡ诱导H9c2心肌细胞构建心肌肥大模型,实验共分6组:... 详细信息

目的真武汤在治疗慢性心力衰竭(Heart Failure,HF)过程中能够改善心律失常,旨在从p38-MAPK通路调控肥大心肌结构重构和电重构角度探讨真武汤治疗HF相关心律失常的作用机制。方法用AngⅡ诱导H9c2心肌细胞构建心肌肥大模型,实验共分6组:正常组(N),模型组(M)和真武汤低剂量组(D)、中剂量组(Z)、高剂量组(G)及抑制剂组(S)。正常组(N)用含有胎牛血清的高糖培养基培养,模型组(M)用含有10^(-6) mol/L浓度的血管紧张素Ⅱ(Angio-tensinⅡ,AngⅡ)培养基处理,低(D)、中(Z)、高(G)剂量组分别予2%、4%、8%体积分数的真武汤含药血清及AngⅡ培养基共同处理,抑制剂组(S)用含有p38MAPK抑制剂SB203580的培养基处理。处理48 h后,镜下观察各组心肌细胞的生长情况,通过酶联免疫吸附试验(Enzyme Linked Immunosorbent Assay,ELISA)法测心肌肥大标志物ANP的含量,用β-半乳糖苷酶染色法检测细胞衰老情况,采用Western blot法检测各组心肌细胞缝隙连接蛋白43(Connexin 43,Cx43)、p38丝裂原激活的蛋白激酶(p38 Mitogen-ctivated Protein Kinase,p38-MAPK)、基质金属蛋白酶2(Matrix Metalloproteinase 2,MMP2)、基金金属蛋白酶9(Matrix Metalloproteinase 9,MMP9)、金属蛋白酶组织抑制剂(Tissue Inhibitor of Metalloprotei-nase1,TIMP1)、p53蛋白的表达情况,采用实时荧光定量PCR(Quantitative Real-time PCR,qPCR)定量分析各组心肌细胞ANP、Cx43、p-Cx43、p38-MAPK、MMP2、MMP9、TIMP1的mRNA转录水平,免疫荧光检测Cx43蛋白的表达和分布情况。结果高剂量的真武汤能够减轻肥大心肌细胞的表面积,中低剂量无明显效果;真武汤能够降低心肌肥大标志物ANP及其mRNA的水平,且其效果与剂量呈正相关;真武汤能改善肥大细胞的衰老情况,效果与抑制剂相似;真武汤能够降低肥大心肌细胞Cx43、p38-MAPK、MMP2、MMP9、p53、p-Cx43蛋白的表达水平及Cx43、p38-MAPK、MMP2、MMP9的mRNA转录水平,且能够增加TIMP1的表达水平及其mRNA转录水平,效果与剂量有关;真武汤能够缓解肥大细胞表面Cx43的分布紊乱及减少该蛋白在细胞侧-侧移位分布。结论真武汤可能通过p38信号通路调控心肌肥大细胞的衰老和纤维化,调节细胞外基质的代谢平衡,维持心肌细胞上Cx43数量、磷酸化水平和分布定位,改善缝隙连接重构,实现对HF心肌结构重构和电重构的统一调节,达到治疗心力衰竭及相关心律失常的目的。

关键词：真武汤心力衰竭结构重构电重构 Cx43 p38-MAPK 缝隙连接基质金属蛋白酶

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Carbene-catalyzed enantioselective seleno-Michael addition as access to antimicrobial active Se-containing heterocycles

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Science china chemistry 2024年第7期67卷 2199-2205页

作者： Hongyan Long Sha Zhao Chunyan Jian Xiuli Wu Fengfei Lu Minghong Liao Fengrui che Xingxing Wu Yonggui Robin chi State Key Laboratory of Green Pesticide Key Laboratory of Green Pesticide and Agricultural BioengineeringMinistry of EducationGuizhou UniversityGuiyang 550025China School of chemistry Chemical Engineeringand BiotechnologyNanyang Technological UniversitySingapore 637371Singapore

Organoseleniums exhibit a diverse set of biological activities that are pivotal for drug discovery and are widely explored in synthetic chemistry and material *** many transformations have been developed for non-enantioselective C–Se bond formations,the catalyst-controlled stereoselective preparation of chiral organoseleniums continues to be of considerable *** particular,there are limited studies on the enantioselective seleno-Michael addition reactions to access chiral selenium functional ***,we disclose a carbene-catalyzed highly enantioselective nucleophilic C–Se bond construction through formal[3+3]annulations between selenocarboxamides and bromoenals,affording seleno-thiazinone products with good yields and excellent *** choice of a weak inorganic base was pivotal to suppressing the unproductive racemization and decomposition of the selenium ***,the catalytically generated chiral selenium-containing heterocyclic products feature remarkable antimicrobial activities that could serve as promising lead scaffolds for further agrochemical development.

关键词： seleno-Michael addition organocatalysis N-heterocyclic carbene seleno-heterocycles antimicrobial activity

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Fabrication of gold nanoparticles with different morphologies in HEPES buffer

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Rare Metals 2010年第2期29卷 180-186页

作者： cheN Rong WU Jiliang LI Hui cheNG Gang LU Zhong che chi-Ming School of chemical Engineering and Pharmacy Key Laboratory for Green Chemical Process(Ministry of Education) Hubei Key Lab of Novel Reactor and Green Chemical Technology Wuhan Institute of Technology Wuhan 430074 China Department of chemistry and the HKU-CAS Joint Laboratory on New Materials The University of Hong Kong Pokfulam Road Hong Kong China

Gold nanoparticles with different morphologies, such as spindle, octahedron, and decahedron were obtained by using different molar ratios of HAuCl4/HEPES in the presence and absence of surfactants at room *** nanoparticles were characterized by X-ray diffraction（XRD）, transmission electron microscopy（TEM）, high-resolution transmission electron microscopy（HRTEM）, scanning electron microcopy（SEM）, energy-dispersive X-rays analysis（EDX）, and selected area electron diffraction（SAED）.The kinetics of the formation of gold nanoparticles in HEPES buffer was studied by UV-visible *** formation of gold nanoparticles was strongly dependent on the concentration of HEPES and pH *** surfactants play a crucial role in the size and shape controlled synthesis of gold nanoparticles.

关键词： inorganic chemistry gold nanoparticle HEPES buffer surfactant

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An　SCF－MS－Xα　Study　of　the　Electronic　Structures　of　Binuclear　and　Trinuclear　Gold（Ⅰ）　Compounds

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chemical Research in chinese Universities 1996年第4期12卷 378-389页

作者： GUO Chun-xiao(Department of chemistry,Jilin University,Changchun,130023)CHAN chi-keung and che chi-ming(Department of chemistry,University of Hongkong,Hongkong) JILIN UNIV DEPT CHEMCHANGCHUN 130023PEOPLES R CHINA UNIV HONG KONG DEPT CHEMHONG KONGHONG KONG

The SCF-Xα-SW molecular orbital calculations were carried out on the modelcompounds of binuclear and trinuclear gold(Ⅰ)using starting potential of Au atom and the Watson *** energy level order of the frontier orbital of a binuclear gold model compound is in agreement with the experimental *** calculated ionization potential of the binuclear model compound is consistent well with the photoelectron spectrum of Au (Me)(PMe_3).The metal-metal interactions are *** calculated electronic absorption spectra of binuclear and trinuclear gold(Ⅰ)are basically in agreement with experimental results.

关键词： s:Electronic structure,SCF-Xα-SW Gold(Ⅰ)

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基于复合阻尼的声学覆盖层吸声效率计算

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舰船科学技术 2022年第5期44卷 32-36页

作者：张帆车驰东上海交通大学船舶海洋与建筑工程学院上海200240

为了提高声学覆盖层的仿真精度,改进原有的计算参数模型。基于集总参数法和传递矩阵法,提出声学覆盖层的一维等效模型。结合有限元法对声学覆盖层计算,计算结果表明,阻尼对吸声效率有显著作用,不同类型阻尼对吸声作用不同,结构阻尼主要... 详细信息

为了提高声学覆盖层的仿真精度,改进原有的计算参数模型。基于集总参数法和传递矩阵法,提出声学覆盖层的一维等效模型。结合有限元法对声学覆盖层计算,计算结果表明,阻尼对吸声效率有显著作用,不同类型阻尼对吸声作用不同,结构阻尼主要影响低频区,粘性阻尼主要影响高频段。根据橡胶材料特性,结合数值计算的结果,提出一种计权的复合阻尼模型,并通过声管实验验证了有效性。提高了声学覆盖层的仿真精度,对声学覆盖层设计有重要意义。

关键词：声学覆盖层复合阻尼吸声效率声管实验

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Promoting interactions between cognitive science and large language models

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The Innovation 2024年第2期5卷 9-10页

作者： Youzhi Qu Penghui Du Wenxin che chen Wei chi Zhang Wanli Ouyang Yatao Bian Feiyang Xu Bin Hu Kai Du Haiyan Wu Jia Liu Quanying Liu Department of Biomedical Engineering Southern University of Science and TechnologyShenzhen 518055China Shanghai AI Laboratory Shanghai 200232China Tencent AI Lab Shenzhen 518057China iFLYTEK AI Research Hefei 230088China School of Medical Technology Beijing Institute of TechnologyBeijing 100081China Institute for Artificial Intelligence Peking UniversityBeijing 100871China Centre for Cognitive and Brain Sciences and Department of Psychology University of MacaoMacao 999078China Department of Psychology Tsinghua UniversityBeijing 100084China

Large language models(LLMs)have made unprecedented progress,demonstrating human-like language proficiency and an extraordinary ability to encode complex *** emergence of high-level cognitive capabilities in LLMs,such as in-context learning and complex reasoning,suggests a path toward the realization of artificial general intelligence(AGI).However,we lack scientific theories and tools to assess and interpret such an emergence of the advanced intelligence of *** intelligence(AI)has been extensively applied in various areas of fundamental science to accelerate scientific research.

关键词： cognitive such language

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