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Yetter–Drinfeld Modules over the Hopf–Ore Extension of the Group Algebra of Dihedral Group

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Acta Mathematica Sinica,English Series 2012年第3期28卷 487-502页

作者： hong zhu Hui Xiang CHEN Department of Information Science School of Mathematical and PhysicalChangzhou University School of Mathematical Science Yangzhou University

Let k be an algebraically closed field of characteristic zero, and Dn be the dihedral group of order 2n, where n is a positive even integer. In this paper, we investigate Yetter-Drinfeld modules over the Hopf-Ore extension A（n,0） of kDn. We describe the structures and properties of simple Yetter Drinfeld modules over A（n, 0）, and classify all simple Yetter-Drinfeld modules over A（n, 0）.

关键词： Dihedral group Hopf-Ore extension Yetter-Drinfeld module

Synthesis of Ti_3AlC_2 by SHS and thermodynamic calculation based on first principles

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Rare Metals 2015年第2期34卷 107-110页

作者： Chun-Cheng zhu Jia zhu Hua Wu hong Lin College of Chemistry and Chemical Engineering Harbin Normal University

In this paper, a self-propagating high-temperature combustion synthesis with the pseudo-hot isostatic pressing process（SHS/PHIP） was employed to fabricate high-pure Ti_3AlC_2（φ 240 mm）. In addition, the first principle with quasi-harmonic approximation was applied for the thermodynamic properties＇ investigation of Ti_2AlC and Ti_3AlC_2, including Gibbs free energy, enthalpy, and *** temperature increasing, Gibbs free energy increases,but enthalpy and entropy decrease. The present work provides the theoretical proof for the synthesis mechanism of Ti_3AlC_2 by SHS/PHIP.

关键词： Ti_3AlC_2 Combustion synthesis Thermodynamics

Catalytic oxidation of pentanethiol on basic nitrogen doped carbon hollow spheres derived from waste tires

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Petroleum Science 2022年第4期19卷 1888-1896页

作者： Jing Luo Wen-Feng Zhang Yan-Chen Wei Ji-Xing Liu Chao Wang Yi-ru Zou Hai-Tao Ju Li-Ping Mu Yan-hong Chao hong-Bing Ji Wen-Shuai zhu School of Chemistry and Chemical Engineering Jiangsu UniversityZhenjiang212013JiangsuChina School of Materials Science and Engineering Jiangsu UniversityZhenjiang212013JiangsuChina School of the Environment and Safety Engineering Jiangsu UniversityZhenjiang212013JiangsuChina College of Chemical Engineering and Environment State Key Laboratory of Heavy Oil ProcessingChina University of Petroleum-BeijingChangping102249BeijingChina School of Chemistry Sun Yat-Sen UniversityGuangzhou510275GuangdongChina

A series of basic nitrogen doped carbon hollow spheres(p-N-C) catalysts derived from waste tires were prepared by a green, facile and environmental “leavening” strategy for the catalytic oxidation of pentanethiol. Compared to pristine carbon, the p-N-C has a higher surface curvature conducive to the enrichment of substrates, leading to an excellent catalytic performance. This increased surface curvature of p-N-C was fabricated on the synergistic effect of two foaming agents((NH4)2 C2 O4 and NaHCO3), and the released gas also endows the spherical shell of p-N-C with a hierarchical porous structure, promoting the accessibility of active sites with pentanethiol. Pyridine-like and pyrrolic-like nitrogen atoms were investigated as reactive sites on the p-N-C to accelerate the electron transfer from sulfur to active surface oxygen and enhance the adsorption/oxidation process. As a result, the optimal p-N-C catalyst exhibits superior adsorption and oxidation performance(99.9%) of pentanethiol, outperforming the “unleavened”catalyst(20.8%). This work offers a new avenue for the fabrication of highly efficient materials for the desulfurization of fuel.

关键词： Carbon hollow spheres Nitrogen-doping Waste tires Leavening strategy Pentanethiol

UAV-assisted cooperative offloading energy efficiency system for mobile edge computing

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Digital Communications and Networks 2024年第1期10卷 16-24页

作者： Xue-Yong Yu Wen-Jin Niu Ye zhu hong-Bo zhu Jiangsu Key Laboratory of Wireless Communications Nanjing University of Posts and Telecommunications Nanjing210003China Engineering Research Centerof Health Service System Based on Ubiquitous Wireless Networks Ministry of EducationNanjng Universityof Posts and Telecommunications Nanjing210003China

Reliable communication and intensive computing power cannot be provided effectively by temporary hot spots in disaster areas and complex terrain ground *** this has greatly developed the application and integration of UAV and Mobile Edge Computing(MEC)to the Internet of Things(loT).However,problems such as multi-user and huge data flow in large areas,which contradict the reality that a single UAV is constrained by limited computing power,still *** to allowing UAV collaboration to accomplish complex tasks,cooperative task offloading between multiple UAVs must meet the interdependence of tasks and realize parallel processing,which reduces the computing power consumption and endurance pressure of *** the computing requirements of the user terminal,delay constraint of a computing task,energy constraint,and safe distance of UAV,we constructed a UAV-Assisted cooperative offloading energy efficiency system for mobile edge computing to minimize user terminal energy ***,the resulting optimization problem is originally nonconvex and thus,difficult to solve *** tackle this problem,we developed an energy efficiency optimization algorithm using Block Coordinate Descent(BCD)that decomposes the problem into three convex ***,we jointly optimized the number of local computing tasks,number of computing offloaded tasks,trajectories of UAV,and offloading matching relationship between multi-UAVs and multiuser *** results show that the proposed approach is suitable for different channel conditions and significantly saves the user terminal energy consumption compared with other benchmark schemes.

关键词： Computation offloading Internet of things(IoT) Mobile edge computing(MEC) Block coordinate descent(BCD)

Reservoir characteristics,formation mechanisms and petroleum exploration potential of volcanic rocks in China

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Petroleum Science 2015年第1期12卷 54-66页

作者： Zhi-Guo Mao ru-Kai zhu Jing-Lan Luo Jing-hong Wang Zhan-Hai Du Ling Su Shao-Min Zhang Research Institute of Petroleum Exploration & Development Petro China State Key Laboratory of Enhanced Oil Recovery Northwest University Xi’an 710069 State Key Laboratory of Continental Dynamics International Iraq FZE Petro China China University of Petroleum

Characterized by complex lithology and strong heterogeneity, volcanic reservoirs in China developed three reservoir space types： primary pores, secondary pores and fractures. The formation of reservoir space went through the cooling and solidification stage （including blast fragmentation, crystallization differentiation and solidification） and the epidiagenesis stage （including metasomatism, filling, weathering and leaching, formation fluid dissolution and tectonism）. Primary pores were formed at the solidification stage, which laid the foundation for the development and transformation of effective reservoirs. Secondary pores were formed at the epidiagenesis stage, with key factors as weathering and leaching, formation fluid dissolution and tectonism. In China, Mesozoic-Cenozoic volcanic rocks developed in the Songliao Basin and Bohai Bay Basin in the east and Late Paleozoic volcanic rocks developed in the Junggar Basin, Santanghu Basin and Ta- rim Basin in the west. There are primary volcanic reser- voirs and secondary volcanic reservoirs in these volcanic rocks, which have good accumulation conditions and great exploration potential.

关键词： Volcanic reservoirs Diagenesis Formation mechanism Hydrocarbon exploration

Comparison Study on the Semiconductive and Dissolution Behaviour of 316L and Alloy 625 in Hydrochloric Acid Solution

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Acta Metallurgica Sinica(English Letters) 2020年第3期33卷 403-414页

作者： zhu Wang Zi-ru Zhang Lei Zhang Zhe Feng Min-Xu Lu Institute for Advanced Materials and Technology University of Science and Technology BeijingBeijing 100083China

The corrosion behaviour of 316L and Alloy 625 was investigated using cyclic polarization,electrochemical impedance spectroscopy,X-ray photoelectron spectroscopy,Auger electron spectroscopy and induced coupled plasma-optical emis sion *** results indicated that Alloy 625 showed better corrosion resistance than 316L and the prolonging immersion time could enhance corrosion resistance of the two *** passive film formed on the surface of 316L exhibited an electronic structure of p-p heterojunction,with Fe3O4 and Cr2O3 enriched in the outer and inner layers,***,Alloy 625 presented the electronic structure of n-p heterojunction dominated by the outer Fe2O3/NiFe2O4 and inner *** resulted in the opposite semiconductive properties of the passive films formed on the two *** the acid solutions,Fe and Mo suffered from selective dissolution while Cr and Ni were relatively *** corrosion rates were mainly dominated by the dissolution of *** 625 presented better corrosion resistance than 316L due to the obviously lower content of Fe and the higher content of Cr and Ni in the passive *** continuously selective dissolution of iron resulted in the increase in Cr/Fe ratio in the passive film,which was responsible for the enhancement in corrosion resistance.

关键词： Stainless steel Induced coupled plasma(ICP) Polarization X-ray photoelectron spectroscopy(XPS) Passive films

Local pointwise convergence of the 3D finite element

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Applied Mathematics(A Journal of Chinese Universities) 2023年第2期38卷 210-222页

作者： LIU Jing-hong zhu Qi-ding College of Science Guangdong University of Petrochemical TechnologyMaoming 525000China School of Mathematics and Statistics Hunan Normal UniversityChangsha 410081China

For an elliptic problem with variable coefficients in three dimensions,this article discusses local pointwise convergence of the three-dimensional(3D)finite ***,the Green's function and the derivative Green's function are ***,some relationship of norms such as L^(2)-norms,W^(1,∞)-norms,and negative-norms in locally smooth subsets of the domainΩis ***,local pointwise convergence properties of the finite element approximation are obtained.

关键词： nite element local convergence Green's function

Advances of Electrochemical and Electrochemiluminescent Sensors Based on Covalent Organic Frameworks

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Nano-Micro Letters 2024年第2期16卷 395-422页

作者： Yue Cao ru Wu Yan‑Yan Gao Yang Zhou Jun‑Jie zhu Key Laboratory for Organic Electronics and Information Displays(KLOEID)and Institute of Advanced Materials(IAM) Nanjing University of Posts and Telecommunications(NJUPT)Nanjing 210023People’s Republic of China State Key Laboratory of Analytical Chemistry for Life Science School of Chemistry and Chemical EngineeringNanjing UniversityNanjing 210023People’s Republic of China

Covalent organic frameworks(COFs),a rapidly developing category of crystalline conjugated organic polymers,possess highly ordered structures,large specific surface areas,stable chemical properties,and tunable pore *** the first report of boroxine/boronate ester-linked COFs in 2005,COFs have rapidly gained popularity,showing important application prospects in various fields,such as sensing,catalysis,separation,and energy *** them,COFs-based electrochemical(EC)sensors with upgraded analytical performance are arousing extensive *** this review,therefore,we summarize the basic properties and the general synthesis methods of COFs used in the field of electroanalytical chemistry,with special emphasis on their usages in the fabrication of chemical sensors,ions sensors,immunosensors,and ***,the emerged COFs in the electrochemiluminescence(ECL)realm are thoroughly covered along with their preliminary ***,final conclusions on state-of-the-art COFs are provided in terms of EC and ECL sensors,as well as challenges and prospects for extending and improving the research and applications of COFs in electroanalytical chemistry.

关键词： Covalent organic frameworks Electrochemistry Electrochemiluminescence Sensors

Determining the Cosmic Equation of State from Gravitational Lensing

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Chinese Physics Letters 1999年第12期16卷 934-936页

作者： zhu Zong-hong CAO Li Beijing Astronomical Observatory Chinese Academy of SciencesBeijing 100012 National Astronomical Observatories Chinese Academy of SciencesBeijing 100012

An independent method is proposed to determine the equation of state, ωx ≡ px/ρx, for the dark energy component in the universe. This method is based on gravitational lensing statistics. An analytically simple expression for the optical depth of gravitational lensing in general Friedmann-Robertson- Walker cosmologies with dark energy component is derived. It is shown that for a flat universe the optical depth depends sensitively on the redshift to the source zs and the equation of state ωx which makes the method proposed here efficient and robust.

关键词： gravitational universe source