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Weighted Norm Inequalities for Toeplitz Type Operator Related to Singular Integral Operator with Variable Kernel

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Analysis in Theory and Applications 2019年第4期35卷 377-391页

作者： yuexiang he Department of Mathematics Jiaozuo UniversityJiaozuo 454003HenanChina

Let Tk,1 be the singular integrals with variable Calderón-Zygmund kernels or ±Ⅰ(the identity operator), let Tk,2 and Tk,4 be the linear operators, and let Tk,3= ±Ⅰ.Denote the Toeplitz type operator by ■ where Mbf = bf, and Ⅰα is the fractional integral operator. In this paper, we investigate the boundedness of the operator on weighted Lebesgue space when b belongs to weighted Lipschitz space.

关键词： Toeplitz type operator variable Calderon-Zygmund kernel fractional integral weighted Lipschitz space

Dynamic constitutive modeling of frozen soil under impact loading

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Chinese Science Bulletin 2014年第26期59卷 3255-3259页

作者： Jianguo Ning yuexiang he Zhiwu Zhu State Key Laboratory of Explosion Science and Technology Beijing Institute of Technology Traction Power State Key Laboratory Southwest Jiaotong University State Key Laboratory of Frozen Soil Engineering Cold and Arid Regions Environmental and Engineering Research InstituteChinese Academy Sciences

In this study, an isotropic hardening constitutive model is presented to study the behavior of frozen soil under impact loading. In plasticity, a modified Drucker–Prager yield function is adopted. Based on the experimental investigations at different strain rates and different temperatures by means of split Hopkinson pressure bar, the Drucker–Prager criterion has been modified with consideration in the effect of strain rate, and the model parameters have been determined. Compared the constitutive model with the experimental results, the predicted tendencies of the model corresponded well to the test curves.

关键词：动态本构模型冲击载荷冻土霍普金森压杆应变速率各向同性屈服函数模型参数

Boundedness Estimates for Commutators of Riesz Transforms Related to Schrödinger Operators

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Analysis in Theory and Applications 2018年第4期34卷 306-322页

作者： Yueshan Wang yuexiang he Department of Mathematics Jiaozuo UniversityJiaozuo 454003HenanChina

Let L =-?+V be a Schr?dinger operator on R^n(n ≥ 3), where the non-negative potential V belongs to reverse H?lder class RH_(q1) for q_1>n/2. Let H_L^p(R^n)be the Hardy space associated with L. In this paper, we consider the commutator[b,T_α], which associated with the Riesz transform T_α= V~α(-?+V)^(-α) with 0 he new Campanato space Λ_β~θ(ρ). We establish the boundedness of [b,T_α] from L^p(R^n) to L^q(R^n) for 1 hen n/(n+ β) < p ≤ 1,1/q = 1/p-β/n. Moreover, we prove that [b,T_α] maps H_L^(n/n+β)(~Rn)continuously into weak L^1(R^n).

关键词： Riesz transform Schr?dinger operator commutator Campanato space Hardy space

Multilinear Fractional Integrals and Commutators on Generalized herz Spaces

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Analysis in Theory and Applications 2016年第2期32卷 103-121页

作者： Yueshan Wang yuexiang he Department of Mathematics Jiaozuo University

Suppose b= （b1,…,bm） E （BMO）^m, Iα,m^∏b is the iterated commutator of b and the m-linear multilinear fractional integral operator Iα,m. The purpose of this paper is to discuss the boundedness properties of Iα... 详细信息

关键词： Multilinear fractional integral generalized herz space commutator Muckenhoupt weight.

Toeplitz Type Operator Associated to Singular Integral Operator with Variable Kernel on Weighted Morrey Spaces

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Analysis in Theory and Applications 2016年第1期32卷 90-102页

作者： yuexiang he Yueshan Wang Department of Mathematics Jiaozuo University

Suppose T^k,l and T^k,2 are singular integrals with variable kernels and mixed homogeneity or ±I （the identity operator）. Denote the Toeplitz type operator by T^b=k=1∑^QT^k,1M^bT^k,2 where M^bf= bf. In this paper, the boundedness of Tb on weighted Morrey space are obtained when b belongs to the weighted Lipschitz function space and weighted BMO function space, respectively.

关键词： Toeplitz type operator singular integral operator variable Calderon-Zygmund kernel weighted BMO function weighted Lipschitz function weighted Morrey space.

Lightweight Si_(3)N_(4)@SiO_(2) ceramic foam for thermal insulation and electromagnetic wave transparency

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Nano Research 2024年第5期17卷 4298-4306页

作者： Zongwei Tong Xiangjie Yan yuexiang Wang Kexun Li Weihai Ma China-Blarus Belt and Road Joint Laboratory on Electromagnetic Environment Effect the 33rd Research Institute of ChinaElectronics Technology Group CorporationTaiyuan 030032China Key Laboratory for Advanced Ceramics and Machining Technology of Ministry of Education School of Material Science and EngineeringTianjin UniversityTianjin 300072China Department of Materials Science and Engineering Jinzhong UniversityJinzhong 030619China

Increasing porosity is one of the most direct ways to improve the thermal insulation and dielectric properties of *** now,many wet methods for preparing Si_(3)N_(4) ceramic foams usually face the problems of complex rheology,long period,and expensive cost,and the reported pore sizes of Si_(3)N_(4) ceramic foams are typically micron-grade,resulting in a lack of competitiveness in thermal insulation and wave-transparent *** this paper,the Si_(3)N_(4)@SiO_(2) ceramic foams were prepared using an efficient dry-method,which combined three processes of low temperature chemical vapor deposition(LTCVD),template,and isostatic *** method has the advantages of simple operation and short preparation period,and can realize near-net size molding and mass *** addition,the evolution mechanisms of honeycomb microstructure and composition of Si_(3)N_(4)@SiO_(2) ceramic foam during sintering were studied by chemical reaction *** as-prepared Si_(3)N_(4)@SiO_(2) ceramic foam possesses low density(0.377 g·cm^(-3)),high compressive strength(7.5 MPa),low thermal conductivity(0.0808 W·m^(-1)·K^(-1)),and excellent dielectric properties(εhe frequency range of 8-18 GHz,and its maximum working temperature in air can reach up to 1100℃.It will be recommended to be applied in the interlayer of Si_(3)N_(4) ceramic radome to improve its thermal insulation and electromagnetic wave transparency performances.

关键词： silicon nitride ceramic foam honeycomb microstructure dielectric properties thermal insulation

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俄日经贸合作升温对中国的影响与启示

社会科学辑刊 2006年第5期 120-124页

作者：何月香辽宁社会科学院世界经济研究所辽宁沈阳110031

近年来,俄日经贸合作呈现出积极发展态势。并可预见,在今后较长一段时期内,俄日经贸合作虽不会继续保持近两年这样的大幅度增长,但也不会出现如前些年那样较长时间的徘徊。“领土问题”不再是俄日经贸合作不可逾越的障碍、俄罗斯经济继... 详细信息

近年来,俄日经贸合作呈现出积极发展态势。并可预见,在今后较长一段时期内,俄日经贸合作虽不会继续保持近两年这样的大幅度增长,但也不会出现如前些年那样较长时间的徘徊。“领土问题”不再是俄日经贸合作不可逾越的障碍、俄罗斯经济继续增长和日本经济持续复苏、“遏制中国”的相同心态以及朝鲜半岛局势缓和等都是推动俄日经贸合作稳定发展的促进因素。俄日经贸合作的升温,将对中日、中俄经贸合作的发展产生一定的影响,也给中国带来某些启示和思考。

关键词：俄罗斯日本经贸合作升温影响启示

Synthesis of carbon nitride in potassium hydroxide molten salt for efficient uranium extraction from radioactive wastewater

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Frontiers of Environmental Science & Engineering 2024年第8期18卷 89-99页

作者： Shuang Liu Junhan Luo Daniel-James Maguire Liyuan Zheng Zhe Wang yuexiang Lu Institute of Nuclear and New Energy Technology Tsinghua UniversityBeijing 100084China Nuclear Research Institute for Future Technology and Policy Seoul National UniversitySeoul 08826Republic of Korea Department of Earth Sciences University of CambridgeCambridge CB23EQUK The MOE Key Laboratory of Resources and Environmental System Optimization College of Environmental Science and EngineeringNorth China Electric Power UniversityBeijing 102206China

Photocatalysis-assisted removal of uranium has been proven as an effective method for the elimination of radioactive pollution from *** this work,carbon nitride materials were synthesized in potassium hydroxide(KOH)molten salt and applied to photocatalytic uranyl *** materials were confirmed to possess the triazine-s-heptazine structure by NMR,XPS and UV-Vis characterization,and exhibited a wider visible light absorption than graphitic carbon nitride(g-C_(3)N_(4)).The photocatalytic activity of the carbon nitride materials was tailored by varying the precursor mass *** carbon nitride obtained at 80%melamine as precursor(K-CN-80)exhibited the highest photocatalytic extraction ability and its photocatalytic reaction rate is 6.6 times faster than that of g-C_(3)N_(4).The influence of sacrificial agents was studied and the results showed that triethanolamine inhibited U(Ⅵ)photoreduction,but methanol can accelerate U(Ⅵ)photoreduction by consuming photogenerated *** unary KOH molten salt synthesis method has exceptional potential applications in the preparation of carbon nitrides,and the obtained products showed potential in extracting U(Ⅵ)from aqueous solutions for use in nuclear fuel industry and for U(Ⅵ)environmental pollution cleanup.

关键词： Uranium Carbon nitride Molten salt Photocatalysis Radioactive wastewater

Non-contact gaseous microplasma electrode as anode for electrodeposition of metal and metal alloy in molten salt

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Chinese Chemical Letters 2024年第4期35卷 166-169页

作者： Junhan Luo Qi Qing Liqin Huang Zhe Wang Shuang Liu Jing Chen yuexiang Lu Institute of Nuclear and New Energy Technology Tsinghua UniversityBeijing 100084China The MOE Key Laboratory of Resources and Environmental System Optimization College of Environmental Science and EngineeringNorth China Electric Power UniversityBeijing 102206China Nuclear Research Institute for Future Technology and Policy Seoul National UniversitySeoul 08826Republic of Korea

Microplasma based on glow discharge could act as a non-contact gaseous electrode and has attracted much attention in both fundamental research and application. herein, with microplasma as the anode,the electrodeposition process of a series of metal and metal alloys in molten salt has been systemically studied. Four metal cations with different valence states, silver(Ag~+), nickel(Ni^(2+)), copper(Cu^(2+)), and iron(Fe^(3+)), could all be reduced on the solid cathode with high current efficiency and the corresponding metal products were of high purity. The electrodeposition of aluminum-lanthanum(Al-Ln) alloy on the aluminum cathode was also successfully carried out with microplasma as the anode, and the same alloy was obtained by using the conventional anode electrode. These results indicated that microplasma anode based on non-contact direct-current(DC) glow discharge is a promising electrode to be applied in molten salt electrolysis.

关键词： Microplasma Anode Molten salt Electrodeposition Al-Ln alloy