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Monge–Ampère Type Equations on Almost Hermitian Manifolds

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Acta Mathematica Sinica,English Series 2023年第5期39卷 749-772页

作者： jiao Gen zhang School of Mathematical Sciences University of Science and Technology of ChinaHefei 230026P.R.China

In this paper we consider the Monge–Ampère type equations on compact almost Hermitian manifolds.We derive C∞a priori estimates under the existence of an admissible C-subsolution.Finally,we obtain an existence resul... 详细信息

关键词： Monge-Ampere type equations almost Hermitian manifold a priori estimates subsolution

The Polynomial Modules over Quantum Group U_(q)(sl3)

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Algebra Colloquium 2022年第4期29卷 663-668页

作者： Limeng Xia Qianqian Cai Jiao Zhang Institute of Applied System Analysis Jiangsu University ZhenjiangJiangsu 212013China Department of Mathematics Shanghai UniversityShanghai 200444China

Let g be a finite dimensional complex simple Lie algebra with Cartan subalgebraη.Then C[η]has a g-module structure if and only if g is of type A or of type C;this is called the polynomial module of rank one,In the quantum version,the rank one polynomial modules over U_(q)(sl_(2))have been classified.In this paper,we prove that the quantum group U_(q)(sl_(3))has no rank one polynomial module.

关键词： quantum group polynomial module rank one

Modified Al negative electrode for stable high-capacity Al-Te batteries

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International Journal of Minerals,Metallurgy and Materials 2022年第4期29卷 896-904页

作者： Xuefeng zhang Shuqiang jiao State Key Laboratory of Advanced Metallurgy University of Science and Technology BeijingBeijing 100083China

Metal aluminum batteries(MABs)are considered potential large-scale energy storage devices because of their high energy density,resource abundance,low cost,safety,and environmental friendliness.Given their high electrical conductivity,high theoretical specific capacity,and high discharge potential,Te is considered a potential positive electrode material for MABs.Nonetheless,the critical issues induced by the chemical and electrochemical dissolution of tellurium and subsequent chemical precipitation on bare Al negative electrodes result in poor cycle stability and low discharge capacity of Al-Te batteries.Here an efficient TiB_(2)-based modified layer has been proposed to address bare Al electrodes(Al/TB).Consequently,the low-voltage hysteresis and long cycle life of the Al/TB negative electrode have been achieved.In addition,the electrochemical performance of the Al-Te battery based on the Al/TB negative electrode is dramatically improved.Furthermore,the modified separator technology is introduced to match with the as-designed Al/TB negative electrode.Therefore,the record-setting long-term cycle stability of up to 500 cycles has been achieved in the Al-Te battery.The facile strategy also opens a potential route for other high-energy density battery systems,such as Al-S and Al-Se batteries.

关键词： metal aluminum battery negative electrode electrochemically inert TiB_(2) tellurium

A Possible γ-Ray Pulsation from PSR J1740-5340B in the Globular Cluster NGC 6397

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Research in Astronomy and Astrophysics 2024年第1期24卷 285-291页

作者： jiao Zheng Pengfei zhang Li zhang Department of Astronomy School of Physics and AstronomyKey Laboratory of Astroparticle Physics of Yunnan ProvinceYunnan UniversityKunming 650091China

Recently, a new radio millisecond pulsar(MSP) J1740-5340B, hosted in the globular cluster(GC) NGC 6397,was reported with a 5.78 ms spin period in an eclipsing binary system with a 1.97 days orbital period. Based on a modified radio ephemeris updated by tool tempo2, we analyze the ~15 yr γ-ray data obtained from the Large Area Telescope on board the Fermi Gamma-ray Space Telescope and detect PSR J1740-5340B's γ-ray pulsation at a confidence level of ~4σ with a weighted H-test value of ~26. By performing a phase-resolved analysis, the γ-ray luminosity in on-pulse interval of PSR J1740-5340B is L_(γ)~ 3.8 × 10^(33) erg s^(-1) using NGC 6397's distance of 2.48 kpc. And γ-rays from the on-pulse part of PSR J1740-5340B contribute ~90% of the total observed γ-ray emissions from NGC 6397. No significant γ-ray pulsation of another MSP J1740-5340A in the GC is detected.Considering that the previous four cases of MSPs in GCs, more data in γ-ray, X-ray, and radio are encouraged to finally confirm the γ-ray emissions from MSP J1740-5340B, especially starving for a precise ephemeris.

关键词： gamma-rays:galaxies (stars:)pulsars:individual(PSR J1740-5340B) (Galaxy:)globular clusters:individual(NGC 6397)

Classification on irreducible Whittaker modules over quantum group Uq(sl3,∧)

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Frontiers of Mathematics in China 2021年第4期16卷 1089-1097页

作者： Limeng XIA Xiangqian GUO Jiao Zhang Institute of Applied System Analysis Jiangsu UniversityZhenjiang 212013China School of Mathematics and Statistics Zhengzhou UniversityZhengzhou 450001China Department of Mathematics Shanghai UniversityShanghai 200444China

We define the Whittaker modules over the simply-connected quantum group U_(q)(sl3,∧),where A is the weight lattice of Lie algebra sl3.Then we completely classify all those simple ones.Explicitly,a simple Whittaker module over U_(q)(sl3,∧)is either a highest weight module,or determined by two parameters z∈C andγ∈C^(*)(up to a Hopf automorphism).

关键词： Quantum group simple Whittaker module Whittaker vector

New insight into adsorption characteristics and mechanisms of the biosorbent from waste activated sludge for heavy metals

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Journal of Environmental Sciences 2016年第7期28卷 248-256页

作者： Yun Zhou Zhiqiang zhang Jiao Zhang Siqing Xia Key Laboratory of Yangtze River Water Environment Ministry of Education College of Environmental Science and Engineering Tongji University State Key Laboratory of Pollution Control and Resource Reuse College of Environmental Science and Engineering Tongji University Swette Center for Environmental Biotechnology Arizona State University School of Civil Engineering and Transportation Shanghai Technical College of Urban Management

The adsorption characteristics and mechanisms of the biosorbent from waste activated sludge were investigated by adsorbing Pb2＋and Zn2＋in aqueous single-metal solutions. A p H value of the metal solutions at 6.0 was beneficial to the high adsorption quantity of the biosorbent. The optimal mass ratio of the biosorbent to metal ions was found to be 2. A higher adsorption quantity of the biosorbent was achieved by keeping the reaction temperature below 55°C. Response surface methodology was applied to optimize the biosorption processes, and the developed mathematical equations showed high determination coefficients（above 0.99 for both metal ions） and insignificant lack of fit（p = 0.0838 and 0.0782 for Pb2＋and Zn2＋, respectively）. Atomic force microscopy analyses suggested that the metal elements were adsorbed onto the biosorbent surface via electrostatic interaction. X-ray photoelectron spectroscopy analyses indicated the presence of complexation（between –NH2,-CN and metal ions） and ion-exchange（between –COOH and metal ions）. The adsorption mechanisms could be the combined action of electrostatic interaction, complexation and ion-exchange between functional groups and metal ions.

关键词： Waste activated sludge Biosorbent Adsorption Metal ions Response surface methodology（RSM）

Method of reverberation ray matrix for static analysis of planar framed structures composed of anisotropic Timoshenko beam members

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Applied Mathematics and Mechanics(English Edition) 2015年第2期36卷 233-242页

作者： Jiao Zhang Guohua NIE School of Aerospace Engineering and Applied Mechanics Tongji University

Based on the method of reverberation ray matrix（MRRM）, a reverberation matrix for planar framed structures composed of anisotropic Timoshenko（T） beam members containing completely hinged joints is developed for static analysis of such structures.In the MRRM for dynamic analysis, amplitudes of arriving and departing waves for joints are chosen as unknown quantities. However, for the present case of static analysis, displacements and rotational angles at the ends of each beam member are directly considered as unknown quantities. The expressions for stiffness matrices for anisotropic beam members are developed. A corresponding reverberation matrix is derived analytically for exact and unified determination on the displacements and internal forces at both ends of each member and arbitrary cross sectional locations in the structure. Numerical examples are given and compared with the finite element method（FEM） results to validate the present model. The characteristic parameter analysis is performed to demonstrate accuracy of the present model with the T beam theory in contrast with errors in the usual model based on the Euler-Bernoulli（EB） beam theory. The resulting reverberation matrix can be used for exact calculation of anisotropic framed structures as well as for parameter analysis of geometrical and material properties of the framed structures.

关键词： planar framed structure anisotropic Timenshenko（T） beam stiffness matrix method of reverberation ray matrix（MRRM） static analysis

Development Strategies in Transition Metal Borides for Electrochemical Water Splitting

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Energy & Environmental Materials 2022年第2期5卷 470-485页

作者： Yihang Yao Zhaoyuan zhang Lifang jiao Key Laboratory of Advanced Energy Materials Chemistry(Ministry of Education) Renewable Energy Conversion and Storage Center(ReCast)College of ChemistryNankai UniversityTianjin 300071China

Electrochemical water splitting is a feasible method for producing environmental benignity energy of hydrogen,while high price and low availability on the earth of noble electrocatalysts constrain their global-scale application.Transition metal borides(TMBs)have displayed unique metalloid characteristic and outstanding performance for oxygen evolution reaction(OER)and hydrogen evolution reaction(HER)in the last few decades.Herein,recent developments of the TMBs for HER and OER are summarized.Initially,the impact factors and relevant evaluation of electrocatalytic performance are described,that is,overpotential,Tafel slope and exchange current density,stability,faradaic efficiency,turnover frequency,mass and specific activities.Moreover,the optimization strategies of borides are emphasized,which principally include coupling with effective substrates,elemental doping,phase modification,interfacial engineering,and morphology control.Finally,in order to reach the goal of application,the remaining challenges and perspectives are given to point out a direction for enhancing the performance of borides.

关键词： borides electrocatalysts hydrogen evolution reaction oxygen evolution reaction

Accelerating materials discovery using machine learning

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Journal of Materials Science & Technology 2021年第20期79卷 178-190页

作者： Yongfei Juan Yongbing Dai Yang Yang Jiao Zhang Shanghai Key Lab of Advanced High-temperature Materials and Precision Forming Shanghai Jiao Tong UniversityShanghai200240China Department of Computer Science and Engineering Shanghai Jiao Tong UniversityShanghai200240China

The discovery of new materials is one of the driving forces to promote the development of modern society and technology innovation,the traditional materials research mainly depended on the trial-and-error method,which is time-consuming and laborious.Recently,machine learning(ML)methods have made great progress in the researches of materials science with the arrival of the big-data era,which gives a deep revolution in human society and advance science greatly.However,there exist few systematic generalization and summaries about the applications of ML methods in materials science.In this review,we first provide a brief account of the progress of researches on materials science with ML employed,the main ideas and basic procedures of this method are emphatically introduced.Then the algorithms of ML which were frequently used in the researches of materials science are classified and compared.Finally,the recent meaningful applications of ML in metal materials,battery materials,photovoltaic materials and metallic glass are reviewed.

关键词： Materials discovery Materials design Materials properties prediction Machine learning Data-driven