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Advances in Manufacturing 2024年第1期12卷 94-107页

作者： Yan Liu qiu Tang Xin-Cheng Tian School of Control Science and Engineering Shandong UniversityJinan250061People’s Republic of China Engineering Research Center of Intelligent Unmanned System Ministry of EducationJinan250061People’s Republic of China School of Mechanical and Electronic Engineering Shandong Jianzhu UniversityJinan250101People’s Republic of China

The automatic cutting of intersecting pipes is a challenging task in *** improved automation and accuracy,this paper proposes a model-driven path planning approach for the robotic plasma cutting of a branch pipe with a single ***,it summarizes the intersection forms and introduces a dual-pipe intersection *** on this model,the moving three-plane structure(a description unit of the geometric characteristics of the intersecting curve)is constructed,and a geometric model of the branch pipe with a single Y-groove is ***,a novel mathematical model for plasma radius and taper compensation is ***,the compensation model and groove model are integrated by establishing movable ***,to prevent collisions between the plasma torch and workpiece,the torch height is planned and a branch pipe-rotating scheme is *** the established models and moving frames,the planned path description of cutting robot is provided in this novel *** accuracy of the proposed method is verified by simulations and robotic cutting experiments.

关键词： Automatic groove cutting of intersecting pipes Model-driven robot path planning Plasma beam radius and taper compensation

Effect of Calcination Temperature on the Microstructure and Surface Properties of a Cu/ZnO Catalyst Derived from Zn_(3)Cu_(2)(OH)_(6)(CO_(3))_(2)

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China Petroleum Processing & Petrochemical Technology 2024年第2期26卷 46-56页

作者： qiu Shiming Wang Shengjie School of Chemistry and Chemical Engineering Guangxi Minzu Normal UniversityChongzuo 532200GuangxiChina Guangxi Key Laboratory for High-value Utilization of Manganese Resources Chongzuo 532200GuangxiChina

The Cu/ZnO catalyst formed upon the calcination of aurichalcite has a uniform distribution of ZnO,which can delay the sintering of Cu species at high *** this study,aurichalcite possessing a nearly pure phase was prepared using the ammonium complex dissociation precipitation method,and the effect of calcination temperature on the structure and surface properties of the derived Cu/ZnO catalyst was *** results show that the calcination temperature determines the particle size and crystallization degree of the Cu/ZnO catalyst and the surface properties of the corresponding copper oxide and reduced ***-temperature calcination is more conducive to reducing the particle size of the Cu/ZnO catalyst,increasing the specific surface area,and generating abundant defect characteristics on the surface,which is key to obtaining highly dispersed copper and copper-specific surface area catalysts by subsequent ***,the Cu/ZnO catalyst derived using a 300℃or 400℃calcination proved to have a higher specific activity per gram of copper than a commercial Cu/Zn/Al *** discovery in this study opens up a new method for the convenient preparation of a high-temperature resistant Cu/Zn methanol reforming catalyst.

关键词： methanol reforming copper zinc oxide lattice defect

Dimension by Dimension Finite Volume HWENO Method for Hyperbolic Conservation Laws

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Communications on Applied Mathematics and Computation 2024年第1期6卷 605-624页

作者： Feng Zheng Jianxian qiu College of Mathematics and Statistics Fujian Normal UniversityFuzhou350117FujianChina School of Mathematical Sciences and Fujian Provincial Key Laboratory of Mathematical Modeling&High-Performance Scientific Computing Xiamen UniversityXiamen361005FujianChina

In this paper,we propose a finite volume Hermite weighted essentially non-oscillatory(HWENO)method based on the dimension by dimension framework to solve hyperbolic conservation *** can maintain the high accuracy in the smooth region and obtain the high resolution solution when the discontinuity appears,and it is compact which will be good for giving the numerical boundary ***,it avoids complicated least square procedure when we implement the genuine two dimensional(2D)finite volume HWENO reconstruction,and it can be regarded as a generalization of the one dimensional(1D)HWENO *** numerical tests are performed to verify the high resolution and high accuracy of the scheme.

关键词： Finite volume Dimension by dimension HWENO Hyperbolic conservation laws

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动力学蒙特卡洛(KMC)模拟薄膜生长

人工晶体学报 2012年第3期41卷 792-797页

作者：周雪飞吴冲唐朝云孔垂岗邱贝贝杨云卢贵武中国石油大学(北京)理学院北京102249

本文以扩散理论为基础,利用KMC模拟方法,考察了温度对薄膜生长速率和表面形貌的影响以及生长表面的粗糙化相变过程。模拟表明,温度升高有利于提高薄膜生长速率,薄膜生长以"成核-岛数增长-岛的长大融合"的方式进行。模拟发现薄膜生长初... 详细信息

本文以扩散理论为基础,利用KMC模拟方法,考察了温度对薄膜生长速率和表面形貌的影响以及生长表面的粗糙化相变过程。模拟表明,温度升高有利于提高薄膜生长速率,薄膜生长以"成核-岛数增长-岛的长大融合"的方式进行。模拟发现薄膜生长初期存在粗糙化相变过程,当温度低于相变温度时,薄膜分层生长,生长速率较慢;当温度高于相变温度时,薄膜表面粗糙度骤然升高,生长速率加快。

关键词：动力学蒙特卡罗计算机模拟微观生长机制相变温度

The joint Laplace transforms for killed diffusion occupation times

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Applied Mathematics(A Journal of Chinese Universities) 2024年第3期39卷 398-415页

作者： LI Ying-qiu CHEN Ye School of Mathematics and Statistics Changsha University of Science and TechnologyChangsha 410114China College of Mathematics and Computational Science Hunan University of Arts and ScienceChangde 415000China

The approach of Li and Zhou(2014)is adopted to find the Laplace transform of occupation time over interval(0,a)and joint occupation times over semi-infinite intervals(-∞,a)and(b,∞)for a time-homogeneous diffusion pr... 详细信息

关键词： time-homogeneous diffusion process occupation time joint occupation time Laplace transform Brownian motion with drift

MMTN晶体与MMTWD晶体的晶格振动及热导率的拉曼光谱研究

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人工晶体学报 2013年第5期42卷 933-937页

作者：杨云孙为张鹏周雪飞邱贝贝孔垂岗卢贵武中国石油大学(北京)理学院北京102249

采用拉曼光谱技术测量了MMTN(MnHg(SCN)4(C2H5NO)2)和MMTWD(MnHg(SCN)4(H2O)2(C3H7NO)2)两类金属有机配合物晶体的拉曼光谱,并对其晶格振动特征峰进行了指认。依据晶格动力学理论以及声子散射模型,推导了晶体热导率与声子寿命及拉曼谱... 详细信息

采用拉曼光谱技术测量了MMTN(MnHg(SCN)4(C2H5NO)2)和MMTWD(MnHg(SCN)4(H2O)2(C3H7NO)2)两类金属有机配合物晶体的拉曼光谱,并对其晶格振动特征峰进行了指认。依据晶格动力学理论以及声子散射模型,推导了晶体热导率与声子寿命及拉曼谱线半峰宽的关系,计算了晶体的热导率,讨论了该类晶体激光损伤的物理机制。

关键词： MMTN晶体 MMTWD晶体热导率拉曼光谱晶格振动激光损伤阈值

La_3Ta_(0.5)Ga_(5.5-x)Al_xO_(14)高温压电晶体材料的声表面波特性研究

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人工晶体学报 2011年第3期40卷 657-661页

作者：邱贝贝卢贵武黄文奇孔垂岗周雪飞杨云中国石油大学(北京)理学院北京102249 北京信息科技大学理学院北京100085

本文计算了La3Ta0.5Ga5.5-xAlxO14(x=0,0.3,0.5)压电晶体的X,Y和Z切型的声表面波速度、机电耦合系数及能流角。计算结果表明了La3Ta0.5Ga5.5-xAlxO14(LTGAx)具有声表面波速度低、机电耦合系数大、存在能流角为零的切型等优点,同时总结出... 详细信息

本文计算了La3Ta0.5Ga5.5-xAlxO14(x=0,0.3,0.5)压电晶体的X,Y和Z切型的声表面波速度、机电耦合系数及能流角。计算结果表明了La3Ta0.5Ga5.5-xAlxO14(LTGAx)具有声表面波速度低、机电耦合系数大、存在能流角为零的切型等优点,同时总结出Y切型为声表面波特性比较好的切型,为LTGAx(x=0,0.3,0.5)晶体的声表面波应用提供了理论依据。

关键词： La3Ta0.5Ga5.5-xAlxO14 声表面波机电耦合系数能流角

Nitrogen availability mediates the effects of roots and mycorrhizal fungi on soil organic carbon decomposition:A meta-analysis

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Pedosphere 2024年第2期34卷 289-296页

作者： Tongshuo BAI Yunpeng qiu Shuijin HU Ecosystem Ecology Laboratory College of Resources and Environmental SciencesNanjing Agricultural UniversityNanjing 210095China Department of Entomology&Plant Pathology North Carolina State UniversityRaleigh NC 27695USA

Plant roots and their associated mycorrhizal fungi critically mediate the decomposition of soil organic carbon(C),but the general patterns of their impacts over a broad geographical range and the primary mediating factors remain *** on a synthesis of 596 paired observations from both field and greenhouse experiments,we found that living roots and/or mycorrhizal fungi increased organic C decomposition by 30.9%,but low soil nitrogen(N)availability(i.e.,high soil C:N ratio)critically mitigated this promotion *** addition,the positive effects of living roots and/or mycorrhizal fungi on organic C decomposition were higher under herbaceous and leguminous plants than under woody and non-leguminous plants,***,there was no significant difference between arbuscular mycorrhizal fungi and ectomycorrhizal fungi in their effects on organic C ***,roots and/or mycorrhizal fungi significantly enhanced the decomposition of leaf litter but not root *** findings advance our understanding of how roots and their symbiotic fungi modulate soil C dynamics in the rhizosphere or mycorrhizosphere and may help improve predictions of soil global C balance under a changing climate.

关键词： arbuscular mycorrhizal fungi ectomycorrhizal fungi leaf litter leguminous plant mycorhizosphere rhizosphere root litter soil C:N ratio

Oligodendrocytes in central nervous system diseases:the effect of cytokine regulation

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Neural Regeneration Research 2024年第10期19卷 2132-2143页

作者： Chengfu Zhang Mengsheng qiu Hui Fu Center for Cognition and Brain Disorders The Affiliated Hospital of Hangzhou Normal UniversityHangzhouZhejiang ProvinceChina Department of Psychiatry National Clinical Research Center for Mental Disordersand National Center for Mental DisordersThe Second Xiangya Hospital of Central South UniversityChangshaHunan ProvinceChina Institute of Life Sciences Key Laboratory of Organ Development and Regeneration of Zhejiang ProvinceCollege of Life and Environment SciencesHangzhou Normal UniversityHangzhouZhejiang ProvinceChina Key Laboratory of Aging and Cancer Biology of Zhejiang Province School of Basic Medical SciencesHangzhou Normal UniversityHangzhouZhejiang ProvinceChina

Cytokines including tumor necrosis factor, interleukins, interferons, and chemokines are abundantly produced in various diseases. As pleiotropic factors, cytokines are involved in nearly every aspect of cellular functions such as migration, survival, proliferation, and differentiation. Oligodendrocytes are the myelin-forming cells in the central nervous system and play critical roles in the conduction of action potentials, supply of metabolic components for axons, and other functions. Emerging evidence suggests that both oligodendrocytes and oligodendrocyte precursor cells are vulnerable to cytokines released under pathological conditions. This review mainly summarizes the effects of cytokines on oligodendrocyte lineage cells in central nervous system diseases. A comprehensive understanding of the effects of cytokines on oligodendrocyte lineage cells contributes to our understanding of central nervous system diseases and offers insights into treatment strategies.

关键词： astrocyte central nervous system disease CXC chemokine cytokine interferonγ interleukin microglia oligodendrocyte oligodendrocyte precursor cell tumor necrosis factorα

An integrated MINLP model for multi-party coordination in downstream oil supply chain

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Petroleum Science 2024年第3期21卷 2066-2079页

作者： Rui qiu Bo Zhang Wei Zhao Ren-Fu Tu Man-qiu He Qi Liao Yong-Tu Liang National Engineering Laboratory for Pipeline Safety/beijing Key Laboratory of Urban Oil and Gas Distribution Technology China University of Petroleum-BeijingFuxue Road No.18Changping DistrictBeijing102249PR China Strategy&Implementation Department PipeChinaDongtucheng Road No.5Chaoyang DistrictBeijing100013PR China

Cooperation among enterprises can bring overall and individual performance improvement,and a smooth coordination method is ***,due to the lack of customized coordination methods,cooperation in the downstream oil supply chain cannot be carried out *** paper intends to propose a multi-party coordination method to promote cooperation between oil shippers and pipeline operator by optimizing oil transportation,oil substitution and pipeline pricing *** integrated game-theoretic modeling and analysis approach is developed to characterize the operation behaviors of all stakeholders in the downstream oil supply *** proposed mixed integer nonlinear programming model constrains supply and demand capacity,transportation routes,oil substitution rules and pipeline freight *** transformation and price discretization are introduced for model linear *** experiments are carried out in the oil distribution system in South *** results show that compared to the business-as-usual scheme,the new scheme saves transportation cost by 3.48%,increases pipeline turnover by 5.7%,and reduces energy consumption and emissions by 7.66%and 6.77%.It is proved that the proposed method improves the revenue of the whole system,achieves fair revenue distribution,and also improves the energy and environmental benefits of the oil supply chain.

关键词： Downstreamoil supplychain Multi-partycoordination Cooperative game Mixed integernonlinear programming model Pipeline transportation Revenue distribution