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The Pressure in Operator Algebras

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Acta Mathematica Sinica,English Series 2008年第6期24卷 983-996页

作者： cheng Jun hou Department of Mathematics Qufu Normal University Qufu 273165 P. R. China

We introduce two notions of the pressure in operator algebras, one is the pressure Pα（π, T） for an automorphism α of a unital exact C^＊-algebra A at a self-adjoint element T in A with respect to a faithful unital ＊-representation π the other is the pressure Pτ,α（T） for an automorphism α of a hyperfinite von Neumann algebra M at a self-adjoint element T in M with respect to a faithful normal α-invariant state τ. We give some properties of the pressure, show that it is a conjugate invaxiant, and also prove that the pressure of the implementing inner automorphism of a crossed product A×α Z at a self-adjoint operator T in A equals that of α at T.

关键词： exact C^*-algebra hyperfinite von Neumann algebra entropy pressure crossed product

Effects of coal seam dip angle on the outburst in coal roadway excavation

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International Journal of Mining Science and Technology 2019年第5期29卷 757-764页

作者： cheng hou Yinghua Zhang Yi Yan University of Science and Technology Beijing Beijing 100083China Department of Mechanical Engineering McGill UniversityMontrealQC H3A 0C3Canada

The prevention and forecast of coal and gas outburst has always been one of the key issues in coal mining *** simulating the process of tunneling in coal seam with different dip angle through FLAC3D software,the dangerous zone in which outburst may occur and the probability of outburst near the working face were predicted through the distribution of stress,displacement and plastic *** we discussed the size of unstable area in the surrounding rock through the distribution of stress and the variation curve of the displacement on the roadway *** results show that,with an increase of the coal seam dip angle,the risk of outburst in the working face rises *** the dangerous areas in which may outburst occur moves to the upper part of coal *** size of unstable area in the surrounding rock increases with the increase of coal seam dip angle.

关键词： Dip angle Stress concentration Plastic zone Displacement Coal and gas outburst

Continuous Orbit Equivalence of Semigroup Actions

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Acta Mathematica Sinica,English Series 2024年第6期40卷 1581-1598页

作者： Xiang Qi QIANG cheng Jun hou School of Mathematical Science Yangzhou UniversityYangzhou 225002P.R.China

We introduce notions of continuous orbit equivalence and its one-sided version for countable left Ore semigroup actions on compact spaces by surjective local homeomorphisms,and characterize them in terms of the corresponding transformation groupoids and their operator *** particular,we show that two essentially free semigroup actions on totally disconnected compact spaces are continuously orbit equivalent if and only if there is a canonical abelian subalgebra preserving C^(∗)-isomorphism between the associated transformation groupoid C^(∗)-*** also give some examples of orbit equivalence,consider the special case of semigroup actions by homeomorphisms and relate continuous orbit equivalence of semigroup actions to that of the associated group actions.

关键词： Semigroup action continuous one-sided orbit equivalence continuous orbit equivalence groupoid C^(∗)-algebras

Rare-earth dialkyl and dihydride complexes bearing monoanionic ancillary ligands

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Science China Chemistry 2011年第12期54卷 2032-2037页

作者： cheng JianHua hou ZhaoMin Organometallic Chemistry Laboratory RIKEN Advanced Science Institute 2-1 Hirosawa Wako Saitama 351-0198 Japan

Rare-earth elements, including scandium, yttrium, and the lanthanides （La-Lu）, possess unique chemical and physical properties, and constitute one of the last frontiers in the periodic table. Rare-earth elements are... 详细信息

关键词：稀土元素复合物轴承配体二氢烷基化学性质香格里拉

Enhanced 4-chlorophenol biodegradation by integrating Fe_(2)O_(3)nanoparticles into an anaerobic reactor:Long-term performance and underlying mechanism

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Frontiers of Environmental Science & Engineering 2022年第8期16卷 107-119页

作者： cheng hou Xinbai Jiang Na Li Zhenhua Zhang Qian Zhang Jinyou Shen Xiaodong Liu Jiangsu Key Laboratory of Chemical Pollution Control and Resources Reuse School of Environmental and Biological EngineeringNanjing University of Science and TechnologyNanjing 210094China Key Laboratory of Biosafety Nanjing Institute of Environmental SciencesNanjing 210042China School of Life and Environmental Science Guilin University of Electronic TechnologyGuilin 541004China

Fe_(2)O_(3)nanoparticles have been reported to enhance the dechlorination performance of anaerobic systems,but the underlying mechanism has not been *** study evaluated the technical feasibility,system stability,microbial biodiversity and the underlying mechanism involved in a Fe_(2)O_(3)nanoparticle-coupled anaerobic system treating 4-chlorophenol(4-CP)*** results demonstrated that the 4-CP and total organic carbon(TOC)removal efficiencies in the Fe_(2)O_(3)-coupled up-flow anaerobic sludge blanket(UASB)were always higher than 97%and 90%during long-term operation,verifying the long-term stability of the Fe_(2)O_(3)-coupled *** 4-CP and TOC removal efficiencies in the coupled UASB increased by 42.90.4%and 27.50.7%compared to the control UASB *** Fe_(2)O_(3)nanoparticles promoted the enrichment of species involved in dechlorination,fermentation,electron transfer and acetoclastic methanogenesis,and significantly enhanced the extracellular electron transfer ability,electron transport activity and conductivity of anaerobic sludge,leading to enhanced 4-CP biodegradation performance.A possible synergistic mechanism involved in enhanced anaerobic 4-CP biodegradation by Fe_(2)O_(3)nanoparticles was proposed.

关键词： Dechlorination Fe_(2)O_(3)nanoparticles Electron transfer Microbial community

Unified Symmetry of Nonholonomic Mechanical Systems with Non-Chetaev＇s Type Constraints

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Communications in Theoretical Physics 2006年第4X期46卷 683-686页

作者： XIA Li-Li LI Yuan-cheng hou Qi-Bao WANG Jing College of Physics Science and Technology China University of Petroleum Dongying 257061 China

Based on the total time derivative along the trajectory of the system, the unified symmetry of nonholonomic mechanical system with non-Chetaev＇s type constraints is studied. The definition and criterion of the unified symmetry of nonholonomic mechanical systems with non-Ohetaev＇s type constraints are given. A new conserved quantity, as well as the Noether conserved quantity and the Hojman conserved quantity, deduced from the unified symmetry, is obtained. Two examples are given to illustrate the application of the results.

关键词： nonholonomic mechanical system of non-Chetaev's type unified symmetry conserved quantity

Preparation of super-aligned carbon nanotube-reinforced nickel-matrix laminar composites with excellent mechanical properties

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International Journal of Minerals,Metallurgy and Materials 2019年第1期26卷 133-141页

作者： Ze-cheng hou Lun-qiao Xiong Yuan-feng Liu Lin Zhu Wen-zhen Li School of Materials Science and Engineering Tsinghua University Tsinghua-Foxconn Nanotechnology Research Center Tsinghua University

A homogeneous and compact super-aligned carbon nanotube(SACNT)-reinforced nickel-matrix composite was successfully prepared by electrodeposition. The mechanical properties of the laminar SACNT/Ni composites were substantially improved compared with those of pure nickel. With increasing content of SACNTs, the tensile strength of the composite increased and the elongation decreased because of the high-strength SACNTs bearing part of an applied load and the fine-grained strengthening mechanism. The nanohardness of the SACNT/Ni composites was improved from 3.92 GPa(pure nickel) to 4.62 GPa(Ni-4 vol%SACNTs). The uniform distribution of SACNTs in the composites and strong interfacial bonding between the SACNTs and the nickel matrix resulted in an improvement of the mechanical properties of the SACNT/Ni composites. The introduced SACNTs refined the nickel grains, increased the amount of crystal twins, and changed the preferred orientation of grain growth.

关键词： nickel-matrix laminar composite super-aligned carbon nanotube electrodeposition mechanical properties

Symmetries and Mei Conserved Quantities of Nonholonomic Controllable Mechanical Systems

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Communications in Theoretical Physics 2006年第3X期46卷 415-418页

作者： XIA Li-Li LI Yuan-cheng WANG Jing hou Qi-Bao College of Physics Science and Technology China University of Petroleum Dongying 257061 China

This paper concentrates on studying the symmetries and a new type of conserved quantities called Mei conserved quantity. The criterions of the Mei symmetry, the Noether symmetry and the Lie symmetry are given. The conditions and the forms of the Mei conserved quantities deduced from these three symmetries are obtained. An example is given to illustrate the application of the result.

关键词： control nonholonomic mechanical system Mei symmetry Noether symmetry Lie symmetry conserved quantity

Lie-Form Invariance of a Type of Non-holonomic Singular Systems

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Communications in Theoretical Physics 2007年第3期47卷 409-412页

作者： WANG Jing LI Yuan-cheng hou Qi-Bao XIA Li-Li College of Physical Science and Technology China University of Petroleum Dongying 257061 China

In this paper, the Lie-form invariance of a type of non-holonomic singular systems is studied. The differential equations of motion of the systems are given. The definition and the criterions of the Lie-form invariance for the systems are presented. The Hojman conserved quantity and the Mei conserved quantity are obtained. An example is given to illustrate the application of the results.

关键词： non-holonomic constraint singular system symmetry conserved quantity