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Mathematic Model and Analytic Solution for a Cylinder Subject to Exponential Function

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Chinese Journal of Mechanical Engineering 2009年第4期22卷 587-593页

作者： liu wen SHAN rui College of Science Yanshan University Qinhuangdao 066004 China

Hollow cylinders are widely used in spacecraft, rockets, weapons, metallurgy, materials, and mechanical manufacturing industries, and so on, hydraulic bulging roll cylinder and hydraulic press work all belong to hollow cylinders. However, up till now, the solution of the cylinder subjected to the pressures in the three-dimensional space is still at the stage of the analytical solution to the normal pressure or the approximate solution to the variable pressure by numerical method. The analytical solution to the variable pressure of the cylinder has not yet made any breakthrough in theory and can not meet accurate theoretical analysis and calculation requirements of the cylindrical in Engineering. In view of their importance, the precision calculation and theoretical analysis are required to investigate on engineering. A stress function which meets both the biharmonic equations and boundary conditions is constructed in the three-dimensional space. Furthermore, the analytic solution of a hollow cylinder subjected to exponential function distributed variable pressure on its inner and outer surfaces is deduced. By controlling the pressure subject to exponential function distributed variable pressure in the hydraulic bulging roller without any rolling load, using a static tester to record the strain supported hydraulic bulging roll, and comparing with the theoretical calculation, the experimental test result has a higher degree of agreement with the theoretical calculation. Simultaneously, the famous Lam6 solution can be deduced when given the unlimited length of cylinder along the axis. The analytic solution paves the way for the mathematic building and solution of hollow cylinder with randomly uneven pressure.

关键词： cylinder analytic solution distributed pressure in the form of exponential function stress function biharmonic equations

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基于压力相关的城市供水管网漏失预警研究

水电能源科学 2024年第1期42卷 139-143页

作者：涂杰刘文睿丁祥吴芬芬中冶南方工程技术有限公司湖北武汉430223 中国市政工程华北设计研究总院有限公司天津300074 长安大学基建处陕西西安710064 中国市政工程西北设计研究院有限公司甘肃兰州730099

近年来极端天气频发,加之我国大部分城市长期存在严重的缺水问题,因此为节约有限的淡水资源,及时发现城市供水管网漏失事故十分必要。首先通过某市供水管网历史压力数据分析了正常运行工况下的压力数据特征;然后探讨了当供水管网发生漏... 详细信息

近年来极端天气频发,加之我国大部分城市长期存在严重的缺水问题,因此为节约有限的淡水资源,及时发现城市供水管网漏失事故十分必要。首先通过某市供水管网历史压力数据分析了正常运行工况下的压力数据特征;然后探讨了当供水管网发生漏失事故时影响漏失点压力变化的因素,并利用FLUENT流体模拟软件进行仿真模拟验证;最后在各种工况压力变化规律的基础上建立了供水管网压力波动阈,当监测压力值超出压力波动阈,综合考虑压力监测点单一时刻的压力波动程度及一个时间周期内的压力变化趋势等多方面的因素,来预警供水管网是否发生漏失事故,并以某市供水管网为例,验证了所提漏失预警方法有效、可行。

关键词：仿真模拟供水管网压力波动漏失预警

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习近平生态文明思想的哲学基础与内生逻辑

华北理工大学学报（社会科学版） 2024年第4期24卷 114-119页

作者：刘文瑞闫翔苏平燕甘肃农业大学马克思主义学院甘肃兰州730070

习近平生态文明思想具有科学完备、系统完整的哲学基础与内在逻辑。“人与自然是生命共同体”论是其哲学立论之基,论证了人与自然的辩证统一关系;“两山”理论是其核心理念,揭示了经济社会发展与生态环境保护之间的辩证统一关系,指明了... 详细信息

习近平生态文明思想具有科学完备、系统完整的哲学基础与内在逻辑。“人与自然是生命共同体”论是其哲学立论之基,论证了人与自然的辩证统一关系;“两山”理论是其核心理念,揭示了经济社会发展与生态环境保护之间的辩证统一关系,指明了我国经济社会的绿色发展之路;环境生产力论是其内在理论依据,指明了我国经济发展要加快绿色转型的内在要求;环境民生论是其宗旨要求,明确了我国加强生态文明建设的价值旨归。深入学习分析习近平生态文明思想的哲学基础及内在逻辑,牢牢把握其深刻内涵,对于加深“两个结合”、推进生态环境治理工作、走人与自然和谐共生的现代化道路具有重要意义。

关键词：生命共同体 “两山”理论环境生产力

Design, Synthesis and Biological Activity of N-Sulfonyl Aromatic Amide Derivatives

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Chinese Journal of Structural Chemistry 2021年第5期40卷 666-674,531页

作者： liu wen-rui HUA Xue-wen ZHOU Sha YUAN Feng-Ying WANG Gui-Qing liu Yi XING Xiao-Ran College of Agriculture Liaocheng UniversityLiaocheng 252000China Collaborative Innovation Center of Zhejiang Province for Green Pesticide School of Forestry and Bio-technologyZhejiang A&F UniversityHangzhou 311300China Liaocheng Center for Disease Control and Prevention Liaocheng 252000China

Fifteen novel N-sulfonyl aromatic amide derivatives were designed and synthesized, and the structures were characterized by 1H-and 13C-NMR, EA and HRMS. The crystal structures of compounds I-8 and I-9 were obtained from X-ray diffraction: I-8 is of triclinic system, Mr = 372.35, space group P2_(1/n) with a = 7.9151(10), b = 8.5637(11), c = 12.2022(15) A, β = 86.865(2)o, V = 807.09(18) A^(3), Z = 2, F(000) = 384, D_(c) = 1.532 g/cm^(3), the final R = 0.0408 and wR = 0.1068 for 2836 unique reflections with 2435 observed ones(I > 2σ(I)). I-9 belongs to triclinic system, M_r = 407.39, space group P2_1/n, with a = 8.4911(8), b = 8.6053(9), c = 14.5808(15) A, β = 77.1190(10)o, V = 995.44(17)A^(3), Z = 2, F(000) = 416, D_(c) = 1.359 g/cm^(3), the final R = 0.0567 and wR = 0.1779 for 3475 unique reflections with 2392 observed ones(I > 2σ(I)). The preliminary bioassay results indicated that the target compounds showed weak nematicidal activity, while compound I-5 displayed good fungicidal activity against Colletotrichum capsici with the inhibition rate of 61.7%.

关键词： heterocyclic amide synthesis crystal structure fungicidal activity nematicidal activity

Cation-Dipole Interaction-Induced Coacervate Underwater Adhesives in Natural Seawater

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Chinese Journal of Polymer Science 2024年第7期42卷 984-991,I0009页

作者： Xu-Fei liu Chong-rui Zhang Hua-wen Peng Qiang Zhao Key Laboratory of Material Chemistry for Energy Conversion and Storage Ministry of EducationSchool of Chemistry and Chemical EngineeringHuazhong University of Science and TechnologyWuhan430074China

Significant progress has been made in wet adhesives for low salinity water,but exploration of general ionic adhesives for natural seawater is less developed because the high salinity could weaken interfacial bonding and shields electrostatic interactions,resulting in adhesion ***,the design of adhesives for natural seawater represents challenges less ***,a cationic polyelectrolyte(PECHIA)containing imidazolacetonitrile unit was explored to prepare adhesives enabled by natural *** combining the ion shielding effect with the“cation-dipole”interactions between PECHIA chains,aqueous solution of the PECHIA underwent coacervation and self-crosslinking in natural seawater,allowing for underwater adhesion to various substrates in *** instantaneous lap-shear and tensile adhesion strengths are 47 and 119 kPa,respectively,while the cured adhesive shows~739 k Pa tensile adhesion in natural *** design of PECHIA enables wet adhesives viable for applications in the diversified scenarios of natural seawater.

关键词： Coacervate Underwater adhesives Seawater Cation-dipole interaction

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基于近似综合法的空间刚体导引机构尺度综合

机械研究与应用 2024年第3期37卷 97-100页

作者：庞典博曲先琨赵诣刘金峰刘文瑞湖北文理学院机械工程学院湖北襄阳441053 长春工业大学机电工程学院吉林长春130012 康复医学与康复工程技术襄阳市重点实验室湖北襄阳441053

目前空间连杆机构尺度综合是机构综合研究的难点问题之一。首先,通过分析空间RCCC刚体导引机构输出的数学模型,提出了空间刚体导引机构综合的分步式降维综合方法;然后,将21维的机构设计问题分4步进行求解,降低了优化变量维度,推导出了... 详细信息

目前空间连杆机构尺度综合是机构综合研究的难点问题之一。首先,通过分析空间RCCC刚体导引机构输出的数学模型,提出了空间刚体导引机构综合的分步式降维综合方法;然后,将21维的机构设计问题分4步进行求解,降低了优化变量维度,推导出了机构实际尺寸的计算公式;最后,通过实际算例证明了所提方法的有效性。所研究结果为非整周期设计要求的空间RCCC机构刚体导引综合问题的求解提供了一种可行的方法。

关键词：近似综合法空间RCCC机构非整周期设计要求刚体导引综合

Effect of post rolling stress on phase transformation behavior of microalloyed dual phase steel

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Journal of Iron and Steel Research International 2024年第3期31卷 688-699页

作者： wen-quan Sun Sheng-yi Yong Tie-heng Yuan Ting-song Yang An-rui He Chao liu rui-chun Guo National Engineering Research Center for Advanced Rolling and Intelligent Manufacturing University of Science and Technology BeijingBeijing 100083China

The slow phase transformation of microalloyed dual phase steel makes the nonuniform stress and temperature fields during the post rolling cooling process have a significant impact on the phase transformation *** the relatively slow phase transformation of DP780 steel within the microalloyed dual phase steel series,the influence of stress on the phase transformation behavior of DP780 steel was *** quantify the nonuniform thermal and stress conditions in the steel coil,a thermo-mechanical coupled finite element model of the hot-rolled strip cooling process was *** on the simulation data,DP780 steel was chosen as the research material,and Gleeble 3500 thermal simulation equipment was used for experimental *** thermal expansion curves were analyzed through regression to establish the dynamic model of DP780 steel phase transformation under ***,metallographic analysis was conducted to determine phase transformation type and grain size of DP780 *** results confirmed that the stress promotes the occurrence of semi-diffusion-type bainite ***,an appropriate level of stress facilitates the growth of bainitic grains,while the increased stress inhibits the growth of ferritic grains.

关键词： Microalloyed dual phase steel Stress Bainitic transformation Grain Finite element method

3D printed silicon-based micro-lattices with ultrahigh areal/gravimetric capacities and robust structural stability for lithium-ion batteries

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Nano Research 2024年第4期17卷 2693-2703页

作者： Jie Fu Dong Wang Yan Li Xianzheng liu rui Zhang Zhiyuan liu Pengdong liu Lijuan Zhang Xuefei Li Guangwu wen School of Materials Science and Engineering Shandong University of TechnologyZibo 255000China Shandong Si-Nano Materials Technology Co. Ltd.Zibo 255000China

Nanostructured silicon anodes have shown extraordinary lithium storage properties for lithium-ion batteries(LIBs)but are usually achieved at low areal loadings(<1.5 mg·cm^(-2))with low areal *** sound electrochemical performance at high loading requires proportionally higher ion/electron currents and robust structural stability in the thicker ***,we report a three-dimensional(3D)printed silicon-graphene-carbon nanotube(3D-Si/G/C)electrode for simultaneously achieving ultrahigh areal/gravimetric capacities at high mass *** periodically arranged vertical channels and hierarchically porous filaments facilitate sufficient electrolyte infiltration and rapid ion diffusion,and the carbonaceous network provides excellent electron transport properties and mechanical integrity,thus endowing the printed 3D-Si/G/C electrode with fast electrochemical reaction kinetics and reversibility at high mass ***,the 3D-Si/G/C with high areal mass loading of 12.9 mg·cm^(-2) exhibits excellent areal capacity of 12.8 mAh·cm^(-2) and specific capacity of 1007 mAh·g^(-1),***-situ optical microscope and ex-situ scanning electron microscope(SEM)confirm that the hierarchically porous filaments with interconnected carbon skeletons effectively suppress the volume change of silicon and maintain stable micro-lattice architecture.A 3D printed 3D-Si/G/C-1||3D-LiFePO_(4)/G full cell holds excellent cyclic stability(capacity retention rate of 78%after 50 cycles)with an initial Coulombic efficiency(ICE)of 96%.This work validates the feasibility of 3D printing on constructing high mass loading silicon anode for practical high energy-density LIBs.

关键词： silicon anode areal capacity three-dimensional(3D)printing lithium-ion batteries

Construction of multifunctional lanthanum manganese mixed nanoparticles mediated by ionic liquids for selective aerobic oxidation of cyclohexane

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Rare Metals 2024年第5期43卷 2205-2221页

作者： Hao Li rui-rui Zhang Ke-Xin Li Shuang Wei Yu-Mei liu rui-Xia liu Beijing Key Laboratory of Ionic Liquids Clean Process CAS Key Laboratory of Green Process and EngineeringState Key Laboratory of Multiphase Complex SystemsInstitute of Process EngineeringChinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China

Selective oxidation of alkanes to produce highvalue chemicals is an essential strategy and means to realize efficient utilization of *** this work,a strategy of lanthanum manganese mixed metal oxides(LMMO)regulated via a facile ionic liquid(IL)-assisted hydrothermal method was proposed to construct the multifunctional catalysts,which exhibited excellent catalytic performance in the selective aerobic oxidation of *** 8.9%cyclohexane conversion with 90%KA oi(cyclohexanol and cyclohexanone)selectivity was achieved over the optimal LMMO catalyst under mild *** effects of anion type,carbon chain length and concentration of ILs on the structure and properties of catalysts were investigated through various characterizations,indicating the structure-directing and template effect of ILs on the multifunctional *** formation of self-assembled spherical nanoparticles followed the"dissolution-nucleation-proliferation"mechanism with the introduction of 1-butyl-3-methylimidazolium hydrogen sulfate,ascribing the synergistic effect between the microenvironment of ILs and the hydrothermal ***,the high reactive oxygen concentration redox capacity,and suitable basic sites of LMMO catalysts mediated by ILs enhance the activation of C-H bonds and molecular oxygen,simultaneously influencing the adsorption and desorption of the substrate.A comprehensive understanding of the high KA oil selectivity and radical reaction mechanism was elucidated based on in situ diffuse reflectance infrared Fourier transform spectroscopy(DRIFTS)and radical trapping *** recycling and regeneration experiments further illuminated that the removal of adsorbed cyclohexanone acting on the LMMO catalyst was the key to achieve high KA oil selectivity.

关键词： Ionic liquids Nanoparticle Multifunctional catalyst Cyclohexane oxidation