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Solutions and Bifurcations of a class of (3+1)-dimensional Nonlinear Models generated by the Jaulent-Miodek hierarchy equation

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Solutions and Bifurcations of a class of (3+1)-dimensional N...

Effect of Fe Addition on Dehydrogenation Performance of Methylcyclohexance over Pt/Al_(2)O_(3)

第十届动力学与控制学术会议

作者： chai song-hao HE Bin LI Jing College of Applied Sciences Beijing University of Technology

In this paper,the(3+1)-dimensional nonlinear evolution equation:w=2(w-2w)-3/4()w-2ww)-3/4w-1/4w-1/2wgenerated by the Jaulent-Miodek hierarchy,is investigated by the bifurcation theory of dynamical *** on the problems,the research are as follows:(1)By using the traveling wave transformation,the(3+l)-dimensional nonlinear model generated by the Jaulent-Miodek hierarchy is changed to a system of ordinary differential *** we analyze the equilibrium bifurcation of the transformation system.(2)By using the theory of dynamical systems,we get the dynamical behavior of the nonlinear transformation *** to the different bifurcation regions of parameters,we obtain the phase portraits of the nonlinear transformation system.(3)Through calculating we obtain all periodic wave solutions,solitary wave solutions,kink wave solutions and anti-kink wave solutions of the(3+1)-dimensional nonlinear evolution equations and obtain the exact expressions of these bounded traveling wave *** we have the waveform graphs of the Jaulent-Miodek model by using the Maple Software.

关键词： (3+1)-dimensional nonlinear evolution equation Bifurcation theory Exact traveling wave solutions Numerical simulations

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China Petroleum Processing & Petrochemical Technology 2024年第1期26卷 12-18页

作者： Tong Fengya Tian hao Wang hao Miao Changxi song Lei Shanghai Research Institute of Petrochemical Technology SINOPEC Shanghai201208

Catalysts with varying Fe contents were prepared using a sequential impregnation method to investigate the effects of Fe addition on the physicochemical properties of Pt/Al_(2)O_(3) and their performance in methylcyclohexane(MCH)*** results demonstrated that the addition of Fe to Pt/Al_(2)O_(3) enhanced the electron density of Pt and improved catalytic activity,while exhibiting negligible influence on the catalytic selectivity for *** the Fe content was 0.057%,the catalyst exhibited the highest MCH consumption rate,which was approximately two times higher than that of the catalyst without ***,the incorporation of Fe inhibited the formation of coke and reduced the quantity of coke deposits on the catalyst,thereby improving its catalytic ***,Fe shows promise as a prospective secondary element for Pt/Al_(2)O_(3) to enhance the MCH dehydrogenation performance.

关键词： methylcyclohexane dehydrogenation hydrogen storage deactivation Fe addition

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A novel cylindrical sandwich plate inspired by beetle elytra and its compressive properties

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Science China Technological Sciences 2024年第11期67卷 3465-3476页

作者： song YiHeng RUAN SiHan hao Ning OKABE YoJi School of Engineering The University of Tokyo School of Civil Engineering Southeast University School of Engineering RMIT University Institute of Industrial Science The University of Tokyo

The design and experimental analysis of a semi-cylindrical structure known as the cylindrical beetle elytron plate(CBEP) were presented. Radial compression tests and finite element simulation were performed on CBEPs under 30° and 45° inclined sliding support constraints, with a comparison made to cylindrical honeycomb plate(CHP). The study aims to investigate the superior compression performance and enhancement mechanisms of CBEPs. The results demonstrate that CBEPs exhibit a 14%–26% increase in specific load-bearing capacity and a 20% increase in specific energy absorption compared with CHPs with equal core wall thickness. Distinct “Z-shaped” tearing failures were observed, with honeycomb plates showing tearing at the center of the honeycomb walls, while beetle elytron plates exhibited tearing along the midline of the trabeculae. Three different stress patterns,including elastic-plastic development stage of arch, plastic hinge node stage, and rigid node stage, were identified and analyzed to explain the mechanical performance improvements and failure characteristics. Considering that structural damage to trabeculae mostly occurs at its junction with the skin, it is recommended to add chamfers to the junctions of CBEP. Therefore, this paper lays the groundwork for the engineering application of CBEP.

关键词： beetle elytron cylindrical beetle elytron plate compression performance failure characteristics enhancement mechanism

Coalbursts in China: Theory, practice and management

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第1期16卷 1-25页

作者： Yishan Pan Yimin song hao Luo Yonghui Xiao Institute of Disaster Rock Mechanics Liaoning UniversityShenyang110036China School of Civil Engineering North China University of TechnologyBeijing100144China College of Computer Science Liaoning UniversityShenyang110036China School of Physics Liaoning UniversityShenyang110036China

Coalburst is one of the most serious disasters that threaten the safe production of coal mines, and this disaster is particularly serious in China. This paper presents an overview of coalbursts in China since 1980s. From the "stress and energy" and "regional and local" perspectives, the achievements in the theory, practice and management of coalbursts in China are systematically summarized. A theoretical system of coalbursts has been formed to reveal the deformational behavior of coalbursts and explain the mechanism of coalbursts. The occurrence conditions of coalbursts are put forward and the critical stress is obtained. The stress index method for risk evaluation of coalbursts before mining is proposed, and the deformation localization prediction method of coalbursts is put forward. The relationship between energy release and absorption in the process of coalbursts is found, and the prevention and control methods of coalbursts, including the regional method, the local method and support, are presented. The safety evaluation index of coalburst prevention and control is put forward. The integrated prevention and control method for coal and gas outbursts is proposed. The prevention and control technology and equipment of coalbursts have also been developed. Amongst them, the distribution law of the critical stress in China coalburst mines is discovered. The technology and equipment for monitoring, prevention and control of coalbursts, as well as for integrated prevention and control of combined coalbursts and other disasters, have been developed. The energy-absorbing and coalburst-preventing support technology for roadways is invented, and key engineering parameters of coalburst prevention and control are pointed out. In China, coalburst prevention and control laws and standards have been developed. Technical standards for coalbursts are formulated, statute and regulations for coal mines are established, and regulatory documents are promoted.

关键词： Coalbursts Rockbursts Dynamic disaster Energy-absorbing support Monitoring and early warning

Highly dispersed MgInCe-mixed metal oxides catalyzed direct carbonylation of glycerol and CO_(2)into glycerol carbonate

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Chinese Journal of Chemical Engineering 2024年第8期72卷 153-163页

作者： Xufang Chen Xin Shu Yanru Zhu Jian Zhang Zhigang chai Hongyan song Zhe An Jing He State Key Laboratory of Chemical Resource Engineering Beijing University of Chemical TechnologyBeijing 100029China Quzhou Institute for Innovation in Resource Chemical Engineering Quzhou 324000China

Glycerol carbonate,an important glycerol value-added product,has been widely used as an active intermediate and inert solvent in the synthesis of cosmetics,detergents,chemical intermediates,polymers,and so *** direct carbonylation from glycerol with CO_(2)is considered a promising route,but still tough work due to the thermodynamic stability and the kinetic inertness of CO_(2).In this work,highlyselective direct carbonylation of glycerol and CO_(2)into glycerol carbonate has been achieved over highly dispersed MgInCe-mixed metal oxides(MgInCe-MMO),which were prepared through the topological transformation derived from the MgInCe-layered double hydroxides(MgInCe-LDHs).By precisely modulating the surface basic-acidic properties and the oxygen vacancies,an efficient carbonylation of glycerol with CO_(2)has been achieved with a selectivity of up to>99%to glycerol *** investigation into the synergistic catalysis of base-acid sites and oxygen vacancies has been clarified.

关键词： Catalytic reaction engineering Glycerol carbonate Direct carbonylation from glycerol Carbon dioxide Mixed metal oxides Synergistic catalysis

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Atomistic understanding of rough surface on the interfacial friction behavior during the chemical mechanical polishing process of diamond

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Friction 2024年第6期12卷 1119-1132页

作者： song YUAN Xiaoguang GUO hao WANG Renke KANG Shang GAO State Key Laboratory of High-performance Precision Manufacturing Dalian University of TechnologyDalian 116024China

The roughness of the contact surface exerts a vital role in *** is still a significant challenge to understand the microscopic contact of the rough surface at the atomic ***,the rough surface with a special root mean square(RMS)value is constructed by multivariate Weierstrass–Mandelbrot(W–M)function and the rubbing process during that the chemical mechanical polishing(CMP)process of diamond is mimicked utilizing the reactive force field molecular dynamics(ReaxFF MD)*** is found that the contact area A/A0 is positively related with the load,and the friction force F depends on the number of interfacial bridge *** the surface roughness will increase the friction force and friction *** model with low roughness and high lubrication has less friction force,and the presence of polishing liquid molecules can decrease the friction force and friction *** RMS value and the degree of damage show a functional relationship with the applied load and lubrication,i.e.,the RMS value decreases more under larger load and higher lubrication,and the diamond substrate occurs severer damage under larger load and lower *** work will generate fresh insight into the understanding of the microscopic contact of the rough surface at the atomic level.

关键词： diamond random roughness reactive force field molecular dynamics(ReaxFF MD) friction Weierstrass-Mandelbrot(W-M)function chemical mechanical polishing(CMP)

Surfactant-assisted crystallization of lysozyme and its mechanism

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Particuology 2024年第7期90卷 199-208页

作者： Yujie song Rongfei Ren Min Su Zhihan Liang Qi hao School of Chemical Engineering Hebei University of TechnologyTianjin 300130China

Surfactants were used to assist in the crystallization of *** types of surfactants with different structures(sodium dodecyl sulfate,cetyltrimethylammonium bromide,or betaine hydrochloride[BH])were *** study indicated that three surfactants were all capable of shortening the crystallization induction time of lysozyme,with BH inducing the shortest crystallization induction time(t=1 min)and the largest crystal size(37μm).The molecular interactions among each of the three surfactants aforementioned and lysozyme were also investigated by *** was found that hydrogen bonding dominantly acted between the carboxyl structure of the surfactant BH and the lysozyme,which produced the most favorable conformation for the self-assembly of lysozyme(promote lysozyme orderly aggregation and shorten the crystallization induction time).On this basis,the mechanism of surfactant-promoted lysozyme crystallization was proposed.

关键词： Protein Crystallization Surfactant Lysozyme Molecular interaction Mechanism

Vertically aligned montmorillonite aerogel-encapsulated polyethylene glycol with directional heat transfer paths for efficient solar thermal energy harvesting and storage

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International Journal of Minerals,Metallurgy and Materials 2024年第5期31卷 907-916页

作者： Qijing Guo Cong Guo hao Yi Feifei Jia Shaoxian song Key Laboratory of Green Utilization of Critical Non-metallic Mineral Resources Ministry of EducationWuhan University of TechnologyWuhan 430070China School of Resources and Environmental Engineering Wuhan University of TechnologyWuhan 430070China Hubei Key Laboratory of Mineral Resources Processing and Environment Wuhan University of TechnologyWuhan 430070China

The conversion and storage of photothermal energy using phase change materials(PCMs)represent an optimal approach for harnessing clean and sustainable solar ***,we encapsulated polyethylene glycol(PEG)in montmorillonite aerogels(3D-Mt)through vacuum impregnation to prepare 3D-Mt/PEG composite *** used as a support matrix,3D-Mt can effectively prevent PEG leakage and act as a flame-retardant barrier to reduce the flammability of ***,3D-Mt/PEG demonstrates outstanding shape retention,increased thermal energy storage density,and commendable thermal and chemical *** phase transition enthalpy of 3D-Mt/PEG can reach 167.53 J/g and remains stable even after 50 heating-cooling ***,the vertical sheet-like structure of 3D-Mt establishes directional heat transport channels,facilitating efficient phonon *** configuration results in highly anisotropic thermal conductivities that ensure swift thermal responses and efficient heat *** study addresses the shortcomings of PCMs,including the issues of leakage and inadequate flame *** achieves the development and design of 3D-Mt/PEG with ultrahigh strength,superior flame retardancy,and directional heat ***,this work offers a design strategy for the preparation of high-performance composite *** 3D-Mt/PEG with vertically aligned and well-ordered array structure developed in this research shows great potential for thermal management and photothermal conversion applications.

关键词： montmorillonite aerogel polyethylene glycol phase change materials solar thermal energy storage flame retardant

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Grain-boundary segregation and grain growth in nanocrystalline substitutional solid solution alloys

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Journal of Materials Science & Technology 2024年第1期168卷 239-249页

作者： Fawei Tang Chao Hou hao Lu Zhi Zhao Xiaoyan song Faculty of Materials and Manufacturing Key Laboratory of Advanced Functional MaterialsMinistry of Education of ChinaBeijing University of TechnologyBeijing 100124China

A model for describing solute segregation at grain boundaries has been developed for substitutional solid solution alloys,which integrates multiple factors from atomic to microstructural scales.A concept of mo-lar Gibbs free energy of segregation was introduced to evaluate the segregating capability of the solute elements in a closed system,through which the influences of grain boundary structure,grain size,ma-terial composition,and external conditions were *** on the evaluation of various energy forms related to solute segregation and grain growth processes,the nature of the thermal stabilization of nanograin structures by solute segregation was disclosed.A criterion for the destabilization of nanostruc-tures,which is determined by the competition of the change rates between the molar Gibbs free energy of segregation and the total energy of grain boundaries with grain size,has been *** study provided guideline to achieve high-temperature stability of nanograin structures of solid solution alloys even for the weakly segregating nanocrystalline systems.

关键词： Substitutional solid solution Grain boundary segregation Thermal stabilization Solute concentration Grain size