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Enzyme-metal nanocomposites for antibacterial applications

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Particuology 2022年第5期20卷 134-139页

作者： Jiarong Xiong Xinyi cai jun ge Key Lab for Industrial Biocatalysis Ministry of EducationDepartment of Chemical EngineeringTsinghua UniversityBeijing 100084China Institute of Biopharmaceutical and Health Engineering Tsinghua Shenzhen International Graduate SchoolShenzhen 518055China

Metal nanoparticles have been used as antibacterial agents widely,and the combined use of enzymes and metal nanoparticles promotes antibacterial activity,achieving a synergistic ***,enzymes decrease the amounts of metals and increase biocompatibility,thereby reducing toxicity of ***,the efficiency of enzymes is hindered when coupled with metals,which causes deactivation in the function of *** can a balance be struck between metals and enzymes?Although the antibacterial mechanism of metal nanoparticles is relatively clear,how enzyme-metal nanocomposites work against bacteria is not ***,we describe several examples on the synthesis of enzyme-metal nanocomposites via co-immobilization or in situ reduction and summarize how enzyme-metal nanocomposites combat microorganisms.

关键词： Enzyme-metal nanocomposites Applications Preparations Antibacterial mechanisms

Synthesis of Calix[4]resorcinarene Core Dendrimers with Peripheral Salicylideneimine Functional Groups

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Chemical Research in Chinese Universities 2006年第4期22卷 537-542页

作者： HAN jun ge Yun YAN Chao-guo College of Chemistry ＆ Chemical Engineering Yangzhou University Yangzhou 225002 P. R. China

First to third-generation calix[4] resorcinarene core dendrimers, compounds 4a, 4b, 7a, 7b, 10a and 10b, were prepared via the divergent method in seven steps with the corresponding tetraphenyl- and tetra （hydroxyphenyl） calix[4] resorcinarenes （compounds 1a, 1b） as the starting material. The repeat units of the polyamidoamines of these dendrimers were obtained by the ammonolysis of ethyl calixarylacetates 2a and 2b with 1,3-diaminopropane, that is, amide derivatives with terminal amino groups, which in turn reacted with ethyl acrylate to give a higher generation of ester derivatives. The structures of these dendrimers were characterized by IR, ^1H and ^13C NMR spoctrometries. The crystal structure of compound 2b with 12 ethoxycarbonylmethoxy groups was determined by X-ray analysis.

关键词： Calixresorcinarene Dendrimer Schiffbase Amide Calixarene

Deformation behavior and processing maps during isothermal compression of TC21 alloy

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Rare Metals 2017年第2期36卷 86-94页

作者： jun Gao Miao-Quan Li ge-jun Liu Shao-Fei Liu School of Materials Science and Engineering Northwestern Polytechnical UniversityXi'an 710072China

In this study,isothermal compression tests were conducted at a Gleeble-1500 simulator at deformation temperatures ranging from 1073 to 1283 K,strain rates ranging from 0.01 to 5.00 s^（-1）,and height reductions ranging from 20%to 60%.The flow stress and apparent activation energy for deformation and constitutive equation were used to characterize the deformation behavior of TC21 alloy during the isothermal *** processing maps combined microstructure observations were established based on dynamic material model（DMM） over a range of strain rates and *** results show that an initial yield drop is observed above 1203 K or at higher strain rates ranging from 1.00 to 5.00 s^-1,and oscillatory flow curves are presented particularly at a strain rate of 5.00 s^-*** has some influence on the apparent activation energy for deformation during the isothermal compression of TC21 *** Q-values and microstructure observation confirm that dynamic recrystallization（DRX） occurs in the β single-phase *** constitutive equation during the isothermal compression of TC21 alloy is developed using the Zener-Hollomon parameter in the exponent-type *** maximum and minimum relative errors between the calculated and the experimental flow stress are 14.1%and 0.3%,*** peak efficiency of power dissipation at a strain of 0.7 is about 0.51 occurring at a deformation temperature of 1073 K and strain rate of 0.01 s^-1,corresponding to an optimal deformation condition of TC21 alloy.

关键词： TC21 alloy Flow stress Apparent activation energy for deformation Constitutive equation Processing Maps

Comparing tractive performance of steel and rubber single grouser shoe under different soil moisture contents

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International Journal of Agricultural and Biological Engineering 2016年第2期9卷 11-20页

作者： ge jun Wang Xiulun Koji Kito Graduate School of Bioresources Mie UniversityTsu 514-8507Japan College of Engineering Anhui Agricultural UniversityHefei 230036China

Steel and rubber are two kinds of materials which are often used for the tracks of off-road *** objective of this study was to compare tractive performances of steel and rubber grouser shoes under different soil moisture *** this study,the tractive performance of single grouser shoe was predicted by soil parameters and three-dimensional shearing *** soil used in this study was clay soil,and ten different soil moisture contents ranged from 8.58%to 54.36%were applied for investigation of soil *** each soil moisture content,the penetration test,direct shearing test,density and soil moisture content measurement have been performed to obtain the required soil *** experimental results showed that thrust and running resistance of steel single grouser shoe had similar trends to those of rubber single grouser *** thrust of rubber single grouser shoe was always greater than that of steel single grouser shoe with the increase of soil moisture content,and as well as the running ***,the traction of rubber single grouser shoe had a different trend to that of steel single grouser *** traction of steel single grouser shoe was always greater than that of rubber single grouser shoe at any given moisture content except at the stage of less than 15%moisture *** the experimental results,it can be concluded that the steel single grouser shoe performed better than rubber single grouser shoe in traction for the soil used in this study.

关键词： steel grouser shoe rubber grouser shoe soil moisture content tractive performance running resistance tracked vehicle

Large Deformation Beam/Cable Element with Implicit Kinematic Model

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Journal of Harbin Institute of Technology(New Series) 2013年第6期20卷 1-8页

作者： Shi-Yi Liu Yao-jun ge State Key Laboratory of Disaster Reduction in Civil Engineering Tongji University

This paper proposes a 3D 2-node element for beams and cables. Main improvements of the element are two new interpolation functions for beam axis and cross-sectional rotation. New interpolation functions employ implicit functions to simulate large deformations. In the translational interpolation function, two parameters which affect lateral deflection geometry are defined implicitly through nonlinear equations. The proposed translational interpolation function is shown to be more accurate than Hermitian function at large deformations. In the rotational interpolation function, twist rate is defined implicitly through a torsional continuity equation. Cross-sectional rotation which is strictly consistent to beam axis is obtained through separate bending rotation interpolation and torsional rotation interpolation. The element model fully accounts for geometric nonlinearities and coupling effects,and thus,can simulate cables with zero bending stiffness. Stiffness matrix and load vector have been derived using symbolic computation. Source code has been generated *** examples show that the proposed element has significantly higher accuracy than conventional 2-node beam elements under the same meshes for geometrically nonlinear problems.

关键词： large deformation analysis 2-node interpolation functions consistent rotational interpolation implicit functions symbolic computationCLC number:TU323.3 Document code:AArticle ID:1005-9113(2013)06-0001-08

不同荷载作用下五边形石墨烯的变形破坏机理研究

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原子与分子物理学报 2025年第6期42卷 51-57页

作者：赵泽若韩同伟李仁葛峻铭王嘉越江苏大学土木工程与力学学院镇江212013

五边形石墨烯是一种完全由碳五元环组成的准二维的亚稳态碳结构,在不同载荷作用下其变形破坏机理仍需进一步研究.本文基于ReaxFF反应力场采用分子动力学方法模拟研究了五边形石墨烯的拉伸、剪切和纳米压痕破坏过程,得到了五边形石墨烯... 详细信息

五边形石墨烯是一种完全由碳五元环组成的准二维的亚稳态碳结构,在不同载荷作用下其变形破坏机理仍需进一步研究.本文基于ReaxFF反应力场采用分子动力学方法模拟研究了五边形石墨烯的拉伸、剪切和纳米压痕破坏过程,得到了五边形石墨烯的拉伸和剪切应力-应变曲线以及压入载荷-位移曲线,系统分析了五边形石墨烯的变形破坏机理,并验证了五边形石墨烯在不同载荷作用下是否表现出塑性变形特征的一致性问题.研究结果表明,通过拉伸或纳米压入等不同加载方式均可准确测出五边形石墨烯的本征力学性能参数,其杨氏模量265.4~285.1 N/m,与第一性原理计算结果一致.研究还发现,五边形石墨烯在拉伸、剪切和纳米压痕过程中均会出现不可逆的塑性变形特征,而引起塑性变形的原因是由于不可逆的碳五元环向碳多元环结构的转变.以上研究结果可为基于五边形石墨烯的微/纳米机电系统的实际应用提供重要指导.

关键词：五边形石墨烯变形破坏机理分子动力学

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Microstructure and mechanical properties of Ti-6Al-4V components fabricated by laser micro cladding deposition

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Rare Metals 2015年第7期34卷 445-451页

作者： Bo Yao Xu-Long Ma Feng Lin Wen-jun ge Key Laboratory for Advanced Materials Processing Technology Ministry of Education of China Key Laboratory for Biomanufacturing and Rapid Forming Technology Department of Mechanical Engineering Tsinghua University Department of Mechanical Engineering Army Aviation Institute of Chinese People’s Liberation Army

Laser micro cladding deposition manufacturing(Ll CDM) is a newly developed rapid manufacturing method for *** Ll CDM technology adopts a novel powder feeding method based on alternating friction and inertia force, and this powder feeding method can effectively improve the accuracy and orientation of the powder injection, resulting in a smaller molten pool size and a higher cooling rate of liquid ***, the components fabricated by Ll CDM could obtain the finer microstructures and the improved mechanical *** is found that the components fabricated by Ll CDM are fully dense free of cracks or pores and exhibit columnar prior b grains with a finer acicular a0 phase *** microhardness(HV0.2) of the thin-wall component is HV 400–HV 500 in the majority part of the cross section and can reach about HV 850 in the top *** ultimate tensile strength(UTS) and elongation show insignificant dependence on the testing directions of the *** UTS is between 1,002 and 1,100 MPa, and the elongation is between 10.0 % and 14.7 %.

关键词： Laser micro cladding deposition Ti-6Al-4V Microstr

Increased Tibetan Plateau vortex activities under 2℃warming compared to 1.5℃warming:NCAR CESM low-warming experiments

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Advances in Climate Change Research 2021年第3期12卷 322-332页

作者： LIN Zhi-Qiang GUO Wei-Dong ge jun WU Run-Qi DU jun School of Atmospheric Sciences Nanjing UniversityNanjing210023China Tibet Institute of Plateau Atmospheric and Environmental Science Lhasa850000China

The Tibetan Plateau vortices(TPVs)are the major rain-producing systems over the Tibetan Plateau(TP).The activities of TPVs are closely related to TP's water source,which supplies fresh water to millions of people in *** of the TPVs can increase understanding about the future of water supply in Asia under global *** this study,the possible activities of TPVs under 1.5℃and 2℃warming scenarios above the pre-industrial level are evaluated through the NCAR CESM(Community Earth System Model)Low-warming(CESM-LW)*** results show that the CESM-LW well reproduces the spatio-temporal characteristics of TPVs in the historical run from 1985 to *** CESM-LW suggests TPVs in warm season(May-September)increase by 15%due to the additional 0.5℃warming by the end of this century(2071—2100).It implies the greater importance of TPVs to the precipitation over the TP in the *** changes of TPVs are closely related to the large-scale circulations *** additional 0.5℃warming strengthens the temperature difference between the TP and its surrounding areas,which results in an enhanced convergence near the TP's surface and divergence in the upper troposphere by about-0.1×10^(-6)and 0.22×10^(6)s^(-1),*** assessment of future TPVs provides a synoptic dynamic perspective on the climate change of precipitation and water resources.

关键词： Tibetan Plateau vortex 2℃and 1.5℃warming Paris agreement Tibet plateau heating Low-warming scenarios

The Number of Circles of a Maximum State of a Plane Graph with Applications

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Acta Mathematicae Applicatae Sinica 2021年第2期37卷 409-420页

作者： Xian-an JIN jun ge Xiao Sheng CHENG Yu-qing LIN School of Mathematical Sciences Xiamen UniversityXiamen 361005 China School of Mathematical Sciences&Laurent Mathematics Center Sichuan Normal UniversityChengdu610066China School of Mathematics and Statistics Huizhou UniversityHuizhouGuangdong 516007China School of Electrical Engineering and Computer Science The Univesity of NewcastleCallaghanNSW 2308Australia

Motivated by the connection with the genus of the corresponding link and its application on DNA polyhedral links,in this paper,we introduce a parameter s_(max)(G),which is the maximum number of circles of states of the link diagram D(G)corresponding to a plane(positive)graph *** show that s_(max)(G)does not depend on the embedding of G and if G is a 4-edge-connected plane graph then s_(max)(G)is equal to the number of faces of G,which cover the results of *** and *** as special cases.

关键词： plane graph number of circles special alternating link genus DNA polyhedral link