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A family of non-conforming crack front elements of quadrilateral and triangular types for 3D crack problems using the boundary element method

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Frontiers of Mechanical Engineering 2019年第3期14卷 332-341页

作者： Guizhong XIE Fenglin ZHOU Hao LI xiaoyu wen Fannian MENG Henan Provincial Key Laboratory of Intelligent Manufacturing of Mechanical Mechanical and Electrical Engineering Institute Zhengzhou University of Light Industry Zhengzhou 450002 China College of Mechanical Engineering Hunan University of Technology Zhuzhou 412007 China

This study focuses on establishing nonconforming crack front elements of quadrilateral and triangular types for 3D crack problems when the dual boundary element method is applied. The asymptotic behavior of the physical variables in the area near the crack front is fully considered in the construction of the shape function. In the developed quadrilateral and triangular crack front elements, the asymptotic term, which captures the asymptotic behavior of the physical variable, is multiplied directly by the conventional Lagrange shape function to form a new crack front shape function. Several benchmark numerical examples that consider pennyshaped cracks and straight-edge crack problems are presented to illustrate the validity and efficiency of the developed crack front elements.

关键词： Taylor expansion crack front elements stress intensity factors dual boundary element method

Implementation of sinh method in integration space forboundary integrals with near singularity in potential problems

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Frontiers of Mechanical Engineering 2016年第4期11卷 412-422页

作者： Guizhong XIE Dehai ZHANG Jianming ZHANG Fannian MENG wenliao DU xiaoyu wen Mechanical and Electrical Engineering Institute Zhengzhou Universityof Light Industry Zhengzhou 450002 China State Key Laboratory forManufacturing Systems Engineering Xi'an Jiaotong University Xi'an710049 China State Key Laboratory of Advanced Design and Manufacturing for Vehicle Body College of Mechanical and Vehicle Engineering HunanUniversity Changsha 410082 China

As a widely used numerical method, boundary element method (BEM) is efficient for computer aided engineering (CAE). However, boundary integrals with near singularity need to be calculated accurately and efficiently to implement BEM for CAE analysis on thin bodies successfully. In this paper, the distance in the denominator of the fundamental solution is first designed as an equivalent form using approximate expansion and the original sinh method can be revised into a new form considering the minimum distance and the approximate expansion. Second, the acquisition of the projection point by Newton-Raphson method is introduced. We acquire the nearest point between the source point and element edge by solving a cubic equation if the location of the projection point is outside the element, where boundary integrals with near singularity appear. Finally, the subtriangles of the local coordinate space are mapped into the integration space and the sinh method is applied in the integration space. The revised sinh method can be directly performed in the integration element. Averification test of our method is proposed. Results demonstrate that our method is effective for regularizing the boundary integrals with near singularity.

关键词： computer aided engineering (CAE) boundary element method (BEM) near singularity sinh method coordinate transformation integration space

Electro-Deposition Pt Catalysts Supported on Carbon-Nanotubes for Methanol Oxidation

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Journal of Harbin Institute of Technology(New Series) 2015年第5期22卷 85-88页

作者： Hailin Song Peixia Yang xiaoyu wen Maozhong An Jinqiu Zhang Chemical Engineering Institute Harbin Institute of Technology

In order to study the properties of supporting Pt catalysts for methanol oxidation,carbon-nanotubes are used by electrochemical deposition method. Different deposition turns,different cyclic voltammetry scanning speeds and processing time with ascorbic acid are investigated in this paper. The micrographs of Pt / CNTs catalysts are characterized by scanning electron microscopy,the electro-catalytic properties of Pt / CNTs catalysts for methanol oxidation are investigated by cycle voltammetry and chronoamperometry. The results show that the size of platinum will be greater with the faster scanning speed. After dissolution in ascorbic acid,Pt nanoparticles disperse uniformly. The obtained Pt / CNTs catalysts show a high electro-catalytic activity and stability.

关键词： Carbon nanotube Pt catalyst Cyclic voltammetry Ascorbic acid

Wide Band Gap Non-Fullerene Small Molecular Acceptors Containing Spirobifluorene and Benzotriazole with Three Different End-Capped Groups for P3HT-Based Organic Solar Cells

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Chinese Journal of Chemistry 2018年第5期36卷 392-398页

作者： xiaoyu wen Bo Xiao Ailing Tang Junyi Hu Chunhe Yang Erjun Zhou Department of Chemistry School of Science Beijing Jiaotong University Beijing 100044 China CAS Key Laboratory of Nanosystem and Hierarchical Fabrication CAS Center for Excellence in Nanoscience National Center for Nanoscience and Technology Beijing 100190 China University of Chinese Academy of Sciences Beijing 200049 China

Spirofluorene （SF） and benzo[d][1,2,3]triazole （BTA） have been considered as promising building blocks to construct n-type photovoltaic materials. Herein, three new small molecule acceptors （SMAs） named BTA21, BTA23 and BTA27 with the structure of A2=A1-D-AI^A2 have been designed, in which SF and BTA were used as a central unit of D and bridged acceptor unit of A1, respectively. In addition, 3-ethylrhodanine, 2-（3-ethyl-4-oxothiazolidin-2-ylidene）malononitrile and malononitrile were chosen as terminal acceptor units to modulate the properties of the final SMAs. Three SMAs show wide optical band gaps （Eg） of 2.19, 2.15 and 2.22 eV, respectively, with gradually down-shift of the lowest unoccupied molecular orbital {LUMO） levels in the order of BTAZl, BTA23 and BTA27 depending on the electron-withdrawing capability of terminal acceptor units. BTA21 shows great advantages with respect to donor poly（3-hexylthiophene）（P3HT） over BTA23 and BTA27, such as well energy-level matching, complementary absorption and proper morpholgy, Concequently, P3HT：BTA21 shows the best power conversion efficiency （PCE） value of 3.28% with an open-circuit voltage （Voc） of 1.02 V, a short-circuit current （Jsc） of 5.45 ***-2 and a fill factor （FF） of 0.59. These results indicate that the terminal acceptor group end-capped in SMAs plays a significant role in controlling their optical, electronic, and photovoltaic properties.

关键词： benzotriazole organic photovoltaic P3HT small molecular acceptor wide band gap

Hydrodechlorination of trifluoro-trichloroethane to chlorotrifluoroethylene:Revealing the deactivation mechanism and regeneration strategy of Pd-Cu/AC catalyst

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Chinese Journal of Chemical Engineering 2024年第6期70卷 261-268页

作者： Song Tian Yicheng Chen xiaoyu wen Bingcheng Li Jian Lu Zile Li Feng Feng Qingtao Wang Qunfeng Zhang Xiaonian Li State Key Laboratory Breeding Base of Green Chemistry Synthesis Technology Institute of Industrial Catalysis of Zhejiang University of TechnologyHangzhou 310014China State Key Laboratory of Fluorine&Nitrogen Chemicals Xi'an Modern Chemistry Research InstituteXi'an 710065China

Chlorotrifluoroethylene(CTFE)is a vital fluorinated olefinic monomer produced through the catalytic hydrodechlorination of trichlorotrifluoroethane(CFC-113),an eco-friendly ***,hydrodechlorination catalysts for olefin production often suffer from poor *** Pd/AC catalyst and Pd-Cu/AC catalyst prepared by co-impregnation method exhibited poor stability,Pd-Cu/AC catalyst with CFC-113 conversion dropping to around 37%after 50 h of hydrodechlorination ***-Emmett-Teller,transmission electron microscopy,X-ray photoelectron spectroscopy,and X-ray diffraction of fresh and deactivated Pd/AC catalysts indicate that the deactivation of Pd/AC catalysts is due to high-temperature agglomeration of *** analysis of fresh and deactivated Pd-Cu/AC catalysts using Brunauer-Emmett-Teller,transmission electron microscopy,and thermogravimetric analysis techniques revealed decreased dispersion of active sites,reduced surface area,catalyst aggregation deactivation,and a significant decrease in Cu ***,the results of NH3-TPD revealed that the acid sites of the catalyst increased significantly.X-ray diffraction spectra indicated the formation of new species,basic copper chloride(Cu_(2)(OH)_(3)Cl),during the *** the reaction progressed,these new species agglomerated,leading to a gradual loss of catalyst ***,the deactivated catalyst was successfully reactivated using a simple alkaline washing method.

关键词： CFC-113 Hydrodechlorination Chlorotrifluoroethylene Catalyst deactivation

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大型仓库疏散应急照明供电系统优化设计

中国照明电器 2025年第1期 74-76页

作者：温晓雨中石化上海工程有限公司

在现代工业与物流中心，大型仓库因其规模庞大和功能复杂，对应急照明系统的需求尤为关键。为了保障仓库的安全与效率，优化应急照明供电系统成为一项必要且挑战性的任务。本文针对大型仓库疏散应急照明供电系统进行了系统的优化设计，... 详细信息

在现代工业与物流中心，大型仓库因其规模庞大和功能复杂，对应急照明系统的需求尤为关键。为了保障仓库的安全与效率，优化应急照明供电系统成为一项必要且挑战性的任务。本文针对大型仓库疏散应急照明供电系统进行了系统的优化设计，详细探讨了应急电源选择与配置、应急照明电路设计及智能控制系统的应用，最终通过优化测试验证了设计方案的有效性。

关键词：大型仓库疏散应急照明供电系统优化设计

Integrated network pharmacology and proteomics to reveal the cognitive improvement effect of Wuzang wenyang Huayu decoction on vascular dementia

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Chinese Medical Journal 2022年第19期135卷 2380-2382页

作者： Yuhao Sun xiaoyu wen Zhuoxian Li Lijing Xu Meng Xia School of Basic Medicine Guangxi University of Chinese MedicineNanningGuangxi 530200China.

To the Editor:Vascular dementia(VD)is a clinical disease characterized_by cognitive dysfunction and intellectual decline caused byvarious *** high incidence of VD in middle-aged and elderly people has become a major medical and social problem *** Since its specific pathogenesis has not been fully elucidated,clinical practice is stillfocused on improving cognition and sAylmteprntoamtivaetilcy,t rweiathtm heignht,seuffcehc taivse pnierascse atanmd faenwd sdidoen eepffeezcitl.s2,i traditional Chinese medicine has drawn medical attention and become a hotspot in the medical research field.

关键词： decoction clinical pathogenesis

基于本体的公理化系统设计语义建模与推理规则

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机械工程学报 2021年第5期57卷 205-221页

作者：王昊琪李浩文笑雨郑州轻工业大学机电工程学院郑州450002

使得计算机理解系统设计的语义并完成自动推理是实现智能制造和基于模型的系统工程的两个重要特征,但现有系统建模语言对语义表达和自动推理的支持有限。第一,为了满足复杂产品系统建模的语义表达要求,在前期工作—基于模型的公理化系... 详细信息

使得计算机理解系统设计的语义并完成自动推理是实现智能制造和基于模型的系统工程的两个重要特征,但现有系统建模语言对语义表达和自动推理的支持有限。第一,为了满足复杂产品系统建模的语义表达要求,在前期工作—基于模型的公理化系统设计(Axiomatic model-based systems engineering,A-MBSD)的基础上,构建对应的本体模型A-MBSD Ontology;通过网络本体语言(Web ontology language 2,OWL2),明确定义系统设计的语义及其之间的关系。第二,为了满足系统建模的推理要求,使用语义网规则语言(Semantic web rule language,SWRL)对设计公理和规则进行定义,支持功能耦合性的判断和最优设计方案的选择。最后,以卫星太阳翼的系统设计为例,证明所构建的本体模型能够明确表达系统设计语义,相应的规则可以自动推理出设计参数所影响的功能需求、功能需求之间的耦合等,避免在试验阶段才发现耦合问题而导致的设计返工,提高系统设计的效率。

关键词：系统设计公理化设计语义网本体推理规则

区域物流业发展不平衡性与集聚度分析——基于中部六省区数据

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商业经济研究 2021年第3期 94-97页

作者：文小羽贵州财经大学商务学院贵州惠水550601

物流是现代经济生活不可或缺的资源配置和价值创造方式,随着物流业结构和功能愈发完善,物流业的发展逐渐成为衡量国家现代化程度和综合国力的重要标志。我国地域辽阔,物流业的发展受到资源要素禀赋和市场环境的影响而呈现出不平衡性,不... 详细信息

物流是现代经济生活不可或缺的资源配置和价值创造方式,随着物流业结构和功能愈发完善,物流业的发展逐渐成为衡量国家现代化程度和综合国力的重要标志。我国地域辽阔,物流业的发展受到资源要素禀赋和市场环境的影响而呈现出不平衡性,不同区域时空差异明显。中部地区作为我国东-中-西流通经济格局过渡的中介地带,随着区域经济快速发展和消费市场的拓展,物流业正呈现快速集聚化趋势。为了明确中部六省区物流业发展不平衡性和集聚度现状,本文采用基尼系数法和区位熵法分别进行数据分析,并根据中部六省区物流业发展的不平衡性和集聚度差异提出相关对策,借以提升中部地区物流业的协调发展水平。研究结论表明:中部六省区物流业不平衡性主要呈现为湖北、湖南、河南与山西、安徽、江西之间的时空差异。基尼系数分解结果显示,2009-2018年中部六省区组间差异为不平衡性贡献了平均77%以上的份额;物流业集聚度分析也显示出湖北、湖南等省份的物流业空间集聚水平较高,而内陆地区山西省、河南省的流通业集聚度较低。

关键词：物流业时空差异性区域物流物流集聚中部六省