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The Existence and Application of Strongly Idempotent Self-orthogonal Row Latin Magic Arrays

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Acta Mathematicae Applicatae Sinica 2018年第4期34卷 693-702页

作者： Yu-fang ZhanG Jing-yuan CHEN dian-hua WU han-tao ZhanG Department of Mathematics Guangxi Normal University Guilin 541004 China School of Mathematics and Statistics Xinyang Normal University Xinyang 464000 China Computer Science Department The University of Iowa Iowa City IA 52242 USA

Let N = {0, 1, ···, n-1}. A strongly idempotent self-orthogonal row Latin magic array of order n（SISORLMA（n） for short） based on N is an n × n array M satisfying the following properties：（1） each row of M is a permutation of N, and at least one column is not a permutation of N;（2） the sums of the n numbers in every row and every column are the same;（3） M is orthogonal to its transpose;（4） the main diagonal and the back diagonal of M are 0, 1, ···, n-1 from left to right. In this paper, it is proved that an SISORLMA（n）exists if and only if n ？ {2, 3}. As an application, it is proved that a nonelementary rational diagonally ordered magic square exists if and only if n ？ {2, 3}, and a rational diagonally ordered magic square exists if and only if n ≠2.

关键词： Diagonally ordered magic square idempotent nonelementary rational self-orthogonal row Latinmagic array self-orthogonal Latin squares with holes

Exact Solutions Expressible in Rational Formal Hyperbolic and Elliptic Functions for Nonlinear Differential-Difference Equation

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Communications in Theoretical Physics 2008年第8期50卷 303-308页

作者： BAI Cheng-Jie ZHAO Hong han Ji-guang School of Communication Shandong Normal University Jinan 250014 China School of Physical Science and Information Engineering Liaocheng University Liaocheng 252059 China

A new approach is presented by means of a new general ansitz and some relations among Jacobian elliptic functions, which enables one to construct more new exact solutions of nonlinear differential-difference equations. As an example, we apply this new method to Hybrid lattice, diseretized mKdV lattice, and modified Volterra lattice. As a result, many exact solutions expressible in rational formal hyperbolic and elliptic functions are conveniently obtained with the help of Maple.

关键词： nonlinear differential-difference equations new approach exact solutions

Ceramic-lined compound copper pipe prepared by SHS process

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中国有色金属学会会刊：英文版 2004年第z1期14卷 106-110页

作者： FU han-guang JIANG Zhi-qiang ZhanG Xiao-hong Department of Mechanical Engineering Tsinghua University Beijing 100084 China Department of Industrial Engineering Zhengzhou Institute of Aeronautics Zhengzhou China Taiyuan Iron and Steel (Group) Company Taiyuan China

Self-propagating high-temperature synthesis(SHS) is a new kind of material synthesis technique, and has characteristics with respect to low energy consumption, short synthetizing time, high production quantity, high product purity and no environmental pollution. When SHS combines with centrifugal casting, ceramic-lined compound copper pipe(CLCCP) can be produced, the inner surface of copper pipe can produce ceramic coatings having good wear and corrosion resistance. In order to increase the densification degree, combining strength and toughness of ceramic layer, the effects of additives such as SiO2, CrO3, Na2B4O7 and ZrO2 are researched, adding SiO2 and CrO3 in thermite, the densification degree of ceramic layer increases, adding Na2 B4 O7 in thermite can increase combining strength, adding ZrO2 in thermite can increase the toughness of ceramic layer. CLCCP is used in tubular billet crystallizer, having excellent service effects and decreasing the production cost of tubular billet.

关键词： SHS ceramic lining compound copper pipe crystallizer

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一种机械设备用起吊装置的设计

机械工程与自动化 2024年第5期 123-124页

作者：韩海敏韩一庆光孟坷河南应用技术职业学院河南郑州450042 河南理工大学能源科学与工程学院河南焦作454000

针对起吊装置在使用过程中存在的功能单一、能耗大、取放效率低、需要人工查找等问题,设计了一种适用于机械设备的改进型起吊装置。基于轻量化、自动化、安全化的设计要求,确定了起吊装置的机械整体结构,详细介绍了装置中的升降机构、... 详细信息

针对起吊装置在使用过程中存在的功能单一、能耗大、取放效率低、需要人工查找等问题,设计了一种适用于机械设备的改进型起吊装置。基于轻量化、自动化、安全化的设计要求,确定了起吊装置的机械整体结构,详细介绍了装置中的升降机构、放置机构及工作原理。该装置升降稳定、控制精准,可节省人工成本,并降低了安全隐患,实现了自动化取放,有利于提高起吊作业的工作效率。

关键词：起吊装置机械设备自动化取放

High-performance magnesium-based thermoelectric materials:Progress and challenges

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Journal of Magnesium and Alloys 2022年第7期10卷 1719-1736页

作者： Zizhen Zhou guang han Xu Lu Guoyu Wang Xiaoyuan Zhou Center of Quantum Materials and Devices College of PhysicsChongqing UniversityChongqing 401331PR China National Engineering Research Center for Magnesium Alloys Chongqing UniversityChongqing 400044PR China Chongqing Institute of Green and Intelligent Technology Chinese Academy of SciencesChongqing 400714PR China Analytical and Testing Center Chongqing UniversityChongqing 401331PR China

Magnesium-based materials have been regarded as promising candidates for large-scale,high-efficiency thermoelectric applications,owing to their excellent dimensionless figure of merit,high abundance,and low *** this review,we comprehensively summarize the recent advances of Mg-based thermoelectrics,including Mg_(2)X(X=Si,Ge,Sn),Mg3(Sb,Bi)_(2),andα-MgAgSb,from both material and device *** electrical and thermal transport properties are first elucidated based on the crystallographic characteristics,band structures,and phonon *** then review the optimization strategies towards higher thermoelectric performance,as well as the device applications of Mg-based thermoelectric materials and the related engineering *** highlighting the challenges and possible solutions in the end,this review intends to offer perspectives on the future research work to further enhance the performance of Mg-based materials for practical applications.

关键词： Thermoelectric Mg-based materials Mg_(2)(Si,Ge,Sn) Mg_(3)Sb_(2) MgAgSb Thermoelectric device

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模块式三维加筋土桥台变形特性载荷试验

中国公路学报 2024年第8期37卷 147-157页

作者：朱晨蔡晓光李雨润李思汉黄鑫冯加煜河北工业大学土木与交通学院中国地震灾害防御中心防灾科技学院地质工程学院北京防灾科技有限公司

三维加筋土桥台因前墙宽度有限，上部荷载作用下前墙与翼墙均会发生变形，仅在平面应变条件下讨论其变形特性显然与实际工程情况不符。为此，以实际桥台为原形，开展大比例尺载荷模型试验，研究三维条件下加筋土桥台顶部沉降、面板水平... 详细信息

三维加筋土桥台因前墙宽度有限，上部荷载作用下前墙与翼墙均会发生变形，仅在平面应变条件下讨论其变形特性显然与实际工程情况不符。为此，以实际桥台为原形，开展大比例尺载荷模型试验，研究三维条件下加筋土桥台顶部沉降、面板水平位移、土体水平位移和筋材应变规律，并将试验结果与现有计算方法结果进行对比分析。结果表明：顶部沉降值随荷载增加而近似线性增大，最大沉降发生在桥座处；桥台在使用极限状态(100 kPa荷载)下的沉降值小于1%H(H为桥台下部结构高度),联邦公路管理局规范中使用极限承载力设计相对保守；桥台前、翼墙的最大面板水平位移均出现在桥台中上部，变形规律基本一致；考虑三维效应的变形修正方法计算结果与实测结果具有较好的一致性；顺桥向筋材应变最大值为1.31%(600 kPa下),潜在破裂面为双折线形；横桥向筋材最大应变都发生在桥座下，在同一高度下整体沿横桥向呈现中间大并向两侧衰减的变化特征；实测筋材拉力最大值与刚度法计算值具有很好的一致性。

关键词：桥梁工程土工合成材料载荷试验加筋土桥台变形三维条件

深圳市学龄前儿童健康素养与健康状况的关系分析

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中国健康教育 2024年第4期40卷 316-320页

作者：曹黎陈丽婷张媛庄润森韩铁光深圳市健康教育与促进中心广东深圳518001 暨南大学广东广州510632

目的分析深圳市学龄前儿童健康素养与健康状况的关系,为制定健康教育干预策略提供依据。方法采用多阶段分层整群抽样方法,对深圳市1514名学龄前儿童进行问卷调查;采用χ^(2)检验和Logistic回归分析对调查结果进行统计分析。结果有效问... 详细信息

目的分析深圳市学龄前儿童健康素养与健康状况的关系,为制定健康教育干预策略提供依据。方法采用多阶段分层整群抽样方法,对深圳市1514名学龄前儿童进行问卷调查;采用χ^(2)检验和Logistic回归分析对调查结果进行统计分析。结果有效问卷回收率为86.66%,深圳市学龄前儿童健康素养水平是66.84%,父母评价健康状况好的比例为80.64%,2周病伤率为18.37%。Logistic回归分析显示,健康素养是学龄前儿童父母评价健康状况和2周病伤情况的影响因素。以不具备健康素养为参照,具备健康素养的学龄前儿童父母评价健康状况较好,OR值为2.689(95%CI:2.030~3.562);具备健康素养的学龄前儿童2周病伤率较低,OR值为0.723(95%CI:0.540~0.968)。结论提升健康素养是改善学龄前儿童健康状况的重要途径,应针对健康素养薄弱环节进行重点干预。

关键词：学龄前儿童健康素养健康状况

Iridium and B(C_(6)F_(5))_(3) co-catalyzed chemoselective deoxygenative reduction of tertiary amides:application to the efficient synthesis and late-stage modification of pharmaceuticals

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Science China Chemistry 2023年第4期66卷 1094-1100页

作者： Feng han guang-Sheng Lu Dong-Ping Wu Pei-Qiang Huang Department of Chemistry Fujian Provincial Key Laboratory of Chemical BiologyCollege of Chemistry and Chemical EngineeringXiamen UniversityXiamen 361005China

The Vaska’s complex—tris(pentafluorophenyl)borane combination was found to be a highly efficient cooperative catalysis system for the hydrosilylative reduction of tertiary amides to yield amines under mild *** reaction shows high chemoselectivity,tolerating halide,phenolyl,alkenyl,nitro,nitrile,ester,azido,ketone,and enone functional *** unsubstituted cyclohexanone carboxamide,two variations were established to achieve either catalytic concomitant reduction of the two carbonyl groups or selective reduction of the amide *** protocol was applied to the efficient synthesis and latestage modification of several pharmaceuticals and ***,we showed that by simply prolonging reaction time to 24–28 h,the reaction can reach an exceptionally high efficiency with turnover number(TON)up to 9.8×10^(6) and turnover frequency(TOF)up to 408,333 at a quite low catalyst loading of 0.00001 mol%(S/C(Ir)=10,000,000).

关键词： amide reduction cooperative catalysis chemoselectivity hydrosilylation amines

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岩石球砾与平板碰撞法向恢复系数

科学技术与工程 2024年第3期24卷 1200-1206页

作者：孙翰卿许龙朱成马新军黄俊光华南理工大学土木与交通学院广州510640 广州建筑股份有限公司广州510000 广东省有色矿山地质灾害防治中心广州510080 广州市建筑集团有限公司广州510030 广州市设计院集团有限公司广州510620

落石法向恢复系数是运动轨迹分析的关键参数。为研究碰撞速率和材料参数对落石法向恢复系数的影响,基于球板碰撞模型,在考虑材料弹塑性基础上建立岩石球砾法向恢复系数理论模型,并利用ABAQUS模拟球板碰撞过程,监测岩石球砾碰撞前后速率... 详细信息

落石法向恢复系数是运动轨迹分析的关键参数。为研究碰撞速率和材料参数对落石法向恢复系数的影响,基于球板碰撞模型,在考虑材料弹塑性基础上建立岩石球砾法向恢复系数理论模型,并利用ABAQUS模拟球板碰撞过程,监测岩石球砾碰撞前后速率的变化。研究结果表明:数值模拟结果与理论计算结果吻合较好,最大差值在5%以内。随着碰撞速率的增大,岩石球砾法向恢复系数逐渐降低,且下降速率逐渐减小;球砾法向恢复系数随着弹性模量的增加而减小,随着弹性极限的增加而增大,且均呈线性关系;泊松比对球砾法向恢复系数影响较小。

关键词：落石法向恢复系数碰撞速率材料参数 Abaqus