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Journal of Thermal Science 2020年第3期29卷 697-707页

作者： ZHANG Zhuqian wang yulei BA Liming Institute of Thermal Engineering School of Mechanical Electronic and Control EngineeringBeijing Jiaotong UniversityBeijing 100044China Beijing Key Laboratory of Flow and Heat Transfer of Phase Changing in Micro and Small Scale Beijing 100044China National Institute of Clean-and-Low-Carbon Energy Beijing 102211China

The temperature uniformity and component concentration distributions in solid oxide fuel cells during operating processes can influence the cell electrochemical and thermal characteristics.A three-dimensional thermal-fluid numerical model including electrochemical reactions and water-gas-shift(WGS)reaction for a single channel solid oxide fuel cell was developed to study the steady-state characteristics,which include distributions of the temperature(T),temperature gradient((35)T/(35)x),and fuel *** was shown that the maximum temperature(Tmax)changed with operating voltage and the maximum temperature gradient(((35)T/(35)x)max)occurred at the inlet of the channel of a solid oxide fuel cell by ***,the natural convection condition had a great influence on T and(35)T/(35)*** thermal stress generated by temperature differences was the key parameter and increasing the convection heat-transfer coefficient can greatly reduce the thermal *** addition,the results also showed that there were lower temperature gradients and lower current density at high working voltage;therefore,choosing the proper operating voltage can obtain better cell performance.

关键词： three-dimensional numerical simulation internal reforming reaction solid oxide fuel cell temperature gradient fuel utilization

Automorphism Groups of Some Finite p-Groups

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Algebra Colloquium 2016年第4期23卷 623-650页

作者： Heguo Liu yulei wang Department of Mathematics Hubei University Wuhan 430062 China Department of Mathematics Henan University of Technology Zhengzhou 450001 China

The automorphism group of G is determined, where G is a nonabelian p-group given by a central extension as 1→Zpm→G→Zp×…×Zp→1 such that its derived subgroup has order p.

关键词： generalized extraspecial p-group symplectic space orthogonal space auto-morphism central extension

The unitary subgroups of group algebras for a class of finite 2-groups with the derived subgroup of order 2

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Science China Mathematics 2024年第9期67卷 1989-2018页

作者： yulei wang Heguo Liu Department of Mathematics Henan University of TechnologyZhengzhou 450001China Department of Mathematics Hainan UniversityHaikou 570228China

Let p be a prime and F be a finite field of characteristic *** that FG is the group algebra of the finite p-group G over the field *** V(FG)denote the group of normalized units in FG and let V_(*)(FG)denote the unitary subgroup of V(FG).If p is odd,then the order of V_(*)(FG)is|F|^((|G-1)/2).However,the case p=2 still is *** this paper,the order of V*(FG)is computed when G is a nonabelian 2-group given by a central extension of the form 1→Z_(2^(n))×Z_(2^(m))→G→Z_(2)×…×Z_(2)→1 and G'≌Z_(2),n,m≥***,a conjecture is confirmed,i.e.,the order of V_(*)(FG)can be divisible by|F|^(1/2(|G|+|Ω1(G)|)-1),where Ω_(1)(G)={g∈G|g^(2)=1}.

关键词： normalized unit unitary subgroup inner abelian p-group central extension

On Non-commuting Sets in Certain Finite p-Groups

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Algebra Colloquium 2015年第4期22卷 555-560页

作者： Heguo Liu yulei wang Department of Mathematics Hubei University Wuhan 430062 China vDepartment of Mathematics Henan University of Technology Zhengzhou 450001 China

Let G be a group. A subset X of G is said to be non-commuting if xy ≠ yx for any x, y ∈ X with x ≠ y. If {X}≥ IYI for any other non-commuting set Y in G, then X is said to be a maximal non-commuting set. In this paper, the bound for the cardinality of a maximal non-commuting set in a finite p-group G is determined, where G is a non-abelian p-group given by a central extension as1 → Zp→ G →Zp ×→ × Zp →1 and its derivedsubgroup has order p.

关键词： generalized extraspecial p-group central product non-commuting set

The Automorphism Group of a Finite p-Group with a Cyclic Frattini Subgroup

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Chinese Annals of Mathematics,Series B 2019年第4期40卷 613-642页

作者： Heguo LIU yulei wang Department of Mathematics Hubei UniversityWuhan 430062China Department of Mathematics Henan University of TechnologyZhengzhou 450001China

Let G be a finite p-group with a cyclic Frattini subgroup. In this paper, the automorphism group of G is determined.

关键词： Finite p-groups Frattini subgroups Automorphisms

A relativistic canonical symplectic particlein-cell method for energetic plasma analysis

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Plasma Science and Technology 2020年第6期22卷 49-59页

作者： yulei wang Feng YUAN Jian LIU Department of Engineering and Applied Physics University of Science and Technology of ChinaHefei 230026People's Republic of China School of Mathematical Sciences University of Science and Technology of ChinaHefei 230026People's Republic of China

A relativistic canonical symplectic particle-in-cell(RCSPIC)method for simulating energetic plasma processes is *** use of the Hamiltonian for the relativistic Vlasov-Maxwell system,we obtain a discrete relativistic canonical Hamiltonian dynamical system,based on which the RCSPIC method is constructed by applying the symplectic temporal discrete *** a 106-step numerical test,the RCSPIC method is proven to possess long-term energy *** ability to calculate energetic plasma processes is shown by simulations of the reflection processes of a high-energy laser(1?×?1020 W cm-2)on the plasma edge.

关键词： canonical symplectic method relativistic particle-in-cell energetic plasma

Asymmetric Transfer Hydrogenation of Diaryl Ketones with Ethanol Catalyzed by Chiral NCP Pincer Iridium Complexes

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Chinese Journal of Chemistry 2022年第10期40卷 1131-1136页

作者： Lu Qian Xixia Tang yulei wang Guixia Liu Zheng Huang School of Chemistry and Material Sciences Hangzhou Institute of Advanced StudyUniversity of Chinese Academy of Sciences1 Sub-lane XiangshanHangzhouZhejiang 310024China The State Key Laboratory of Organometllic Chemistry Shanghai Institute of Organic ChemistryUniversity of Chinese Academy of SciencesChinese Academy of Sciences345 Lingling RoadShanghai 200032China School of Physical Science and Technology Shanghai Tech University100 Haike RoadShanghai 201210China Chang-Kung Chuang Institute East China Normal UniversityShanghai 200062China

The use of a chiral(NCP)Ir complex as the precatalyst allowed for the discovery of asymmetric transfer hydrogenation of diaryl ketones with ethanol as the hydrogen source and *** reaction was applicable to various ortho-substituted diaryl keontes,affording benzhydrols in good yields and *** protocol could be carried out in a gram scale under mild reaction *** utility of the catalytic system was highlighted by the synthesis of the key precursor of(S)-neobenodine.

关键词： Asymmetric transfer hydrogenation Benzhydrols Diaryl ketones Ethanol Iridium

NCP-Type Pincer Iridium Complexes Catalyzed Transfer-Dehydrogenation of Alkanes and Heterocycles

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Chinese Journal of Chemistry 2020年第8期38卷 837-841页

作者： yulei wang Lu Qian Zhidao Huang Guixia Liu Zheng Huang State Key Laboratory of Organometallic Chemistry Center for Excellence in Molecular SynthesisShanghai Institute of Organic ChemistryUniversity of Chinese Academy of SciencesChinese Academy of Sciences345 Lingling RoadShanghai 200032China China School of Chemistry and Material Sciences Hangzhou Institute of Advanced StudyUniversity of Chinese Academy of Sciences1 Sub-lane XiangshanHangzhouZhejiang 310024China Chang-Kung Chuang Institute East China Normal UniversityShanghai 200062China

A series of NCP-type pincer iridium complexes,(RNCCp)IrHCl(2a-2c)and(BQ-NCOP)IrHCl 3,have been studied for catalytic transfer alkane *** 3 containing a rigid benzoquinoline backbone exhibits high activity and robustness in dehydrogenation of alkanes to form *** more importantly,this catalyst system was also highly effective in the dehydrogenation of a wide range of heterocycles to furnish heteroarenes.

关键词： backbone alkanes complexes

Structure and Mechanical Performance of Nitrogen Doped Diamond-like Carbon Films

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Journal of Materials Science & Technology 2007年第4期23卷 491-494页

作者： Huayu ZHANG Liang-xue LIU yulei wang Hongtao MA Fanxin LIU Harbin Institute of Technology Shenzhen Graduate School Shenzhen518055 China SAE Technologies Development （Dongguan） Co. Ltd. Dongguan 523087 China

Nitrogen doped diamond-like carbon （DLC：N） films were prepared by electron cyclotron resonance chemical vapor deposition （ECR-CVD） on polycrystalline Si chips. Film thickness is about 50 nm. Auger electron spectroscopy （AES） was used to evaluate nitrogen content, and increasing N2 flow improved N content from 0 to 7.6%. Raman and X-ray photoelectron spectroscopy （XPS） analysis results reveal CN-sp^3C and N-sp^2C structure. With increasing the N2 flow, sp^3C decreases from 73.74% down to 42.66%, and so does N-sp^3C from 68.04% down to 20.23%. The hardness decreases from 29.18 GPa down to 19.74 GPa, and the Young＇s modulus from 193.03 GPa down to 144.52 GPa.

关键词： Nitrogen doped diamond-like carbon films ECR-CVD Structure Mechanical performance

Path-following control of autonomous ground vehicles using triple-step model predictive control

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Science China(Information Sciences) 2020年第10期63卷 264-266页

作者： yulei wang Hongyu ZHENG Changfu ZONG Hongyan GUO Hong CHEN State Key Laboratory of Automotive Simulation and Control Jilin University Department of Control Science and Engineering Jilin University

Dear editor,Autonomous ground vehicles (AGVs) equipped with a variety of advanced sensor systems exemplify the recent advances in modern automobile industry and have been receiving significant research interest from academia to industry owing to their prospect to reduce traffic congestion and traffic *** core feature of AGVs refers to any

关键词： Autonomous ground vehicles Model predictive control path following triple-step control constraints