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On a Certain Sum-product Estimate in Fields of Prime Order

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Acta Mathematica Sinica,English Series 2014年第11期30卷 1861-1866页

作者： Bo qing xue Academy of Mathematics and Systems Science Chinese Academy of Sciences

Let Fp be the finite field of p elements with p *** A is a subset of Fp and g is an element of F＊p with order ν,then max{｜A ＋ g·A｜,｜A·A｜} （ν/（ν ＋｜A｜2））1/12｜A｜13/12.

关键词： Sum-product estimate different sets fields of prime order

基于两阶段DEA模型的江苏省动力电池行业回收效率评价研究

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价值工程 2025年第1期44卷 9-11页

作者：张雪晴张晓青江苏师范大学商学院徐州221116

本文选取江苏省2014年至2023年30家动力电池回收企业的实际数据,通过构建DEA模型对这些行业的回收效率进行评价分析。研究结果表明:第一,近十年以来,江苏省动力电池回收行业的回收效率总体处于较低水平,还有很大的提高余地。第二,近十... 详细信息

本文选取江苏省2014年至2023年30家动力电池回收企业的实际数据,通过构建DEA模型对这些行业的回收效率进行评价分析。研究结果表明:第一,近十年以来,江苏省动力电池回收行业的回收效率总体处于较低水平,还有很大的提高余地。第二,近十年以来,江苏省动力电池回收行业的配置效率处于不断提高阶段。

关键词： DEA模型动力电池回收行业回收效率

维普期刊数据库博看期刊

Microstructure of ferrospheres in fly ashes: SEM, EDX and ESEM analysis

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2008年第11期9卷 1595-1600页

作者： qing-feng xue Sheng-gao LU Zhejiang Provincial Key Laboratory of Subtropical Soil and Plant Nutrition College of Environmental and Resource Sciences Zhejiang University Hangzhou 310027 China

Ferrospheres in fly ashes from a coal-fired power plant were extracted by a magnetic separation technique and their microstructure was studied by scanning electron microscopy (SEM), energy dispersive X-ray analysis (EDX) and environmental scanning electron microscopy (ESEM). Ferrospheres in fly ashes show significant iron enrichment compared to their respective fly ashes. Iron oxides in ferrospheres mainly occur as minerals magnetite (Fe3O4) and hematite (α-Fe2O3), which are derived mainly from the decomposition and oxidation of iron-bearing minerals in coal during combustion. EDX data indicate that ferrospheres also contain Si, S, Al and Ca resulting from quartz, mullite, anhydrite and amorphous materials. A large percentage of ferrospheres are commonly 5～50 μm in size. The microstructure of ferrospheres includes smooth, polygonal, dendritic, granular and molten drop characteristics. SEM coupled with EDX provided fast and accurate results of the microstructure and chemical composition of ferrospheres, and helped us to assess environmental issues related to the disposal and utilization of fly ashes.

关键词： Fly ash Ferrosphere Microstructure Scanning electron microscopy (SEM)

Influence of Cl substitution on the electronic structure and catalytic activity of ceria

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Science China Chemistry 2015年第4期58卷 601-606页

作者： Li-Li Yin xue-qing Gong Key Laboratory for Advanced Materials Centre for Computational Chemistry and Research Institute of Industrial Catalysis East China University of Science and Technology

Cl-containing cerium dioxide(Ce O2) catalysts have been found to exhibit unique catalytic activities. In the present work, using density functional theory calculations with the inclusion of on-site Coulomb correction, we systematically studied the effect of Cl on the physicochemical properties of Ce O2 surfaces by substituting one subsurface O with Cl. The calculated results show that substituting an O atom with a Cl atom results in structural distortion and the reduction of one surface Ce4+ cation to Ce3+. The protruding Ce3+ cation greatly improves the adsorption energy of O2 to produce an active O2- species, and maintains the catalytic oxidation cycle of CO on Ce O2(110). These results may help us obtain a better understanding of Cl-ceria interacting systems and provide some guidance for the design of effective Ce O2-based catalysts.

关键词： cerium dioxide Cl substitution DFT+U O2 adsorption CO oxidation

Open-Shell Oligomers and Polymers: Theory, Characterization Methods, Molecular Design, and Applications

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Chinese Journal of Polymer Science 2024年第4期42卷 417-436页

作者： xue-qing Wang Cheng Song Ting Lei Key Laboratory of Polymer Chemistry and Physics(Ministry of Education) School of Materials Science and EngineeringPeking UniversityBeijing100871China

Open-shell oligomers and polymers have exhibited intriguing electronic and magnetic properties, making them highly desirable for a wide range of applications, including ambipolar organic field-effect transistors (OFETs), photodetectors, organic thermoelectrics, and spintronics. Although open-shell ground states have been observed in certain small molecules and doped organic semiconductors, the exploration of open-shell ground-state conjugated polymers is still limited, and the strategies for designing these polymers remain obscure. This review aims to briefly introduce the theory and characterization methods of open-shell conjugated polymers, along with an overview of recent progress and applications. The objective is to stimulate further advancements and investigations in this promising area by shedding light on the potential of open-shell conjugated polymers and the challenges that lie ahead.

关键词： Conjugated polymers Open-shell molecules High-spin ground state Donor-acceptor(D-A)polymers Optoelectronic and magnetic properties

Non-commutative Arithmetics on Thompson's Monoid

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Acta Mathematica Sinica,English Series 2021年第10期37卷 1586-1626页

作者： Bo qing xue Institute of Mathematical Sciences ShanghaiTech UniversityShanghai 201210P.R.China

The main purpose of this paper is to define prime and introduce non-commutative arithmetics based on Thompson's group *** primes in a non-abelian monoid is highly non-trivial,which relies on a concept called"castling".Three types of castlings are essential to grasp the *** divisor functionτon Thompson's monoid S satisfiesτ(uv)≤τ(u)τ(v)for any u,v∈*** the limitτ_(0)(u)=lim_(n→∞)(τ(u~n))^(1/n)*** quantityC(S)=sup_(1≠u∈S)τ_(0)(u)/τ(u)describes the complexity for castlings in *** show thatC(S)=***,the MCbius function on S is *** the Liouville functionCon S is studied.

关键词： Thompson's group non-commutative arithmetics castling complexity divisor function M?bius function

Weighted Variation Inequalities for Singular Integrals and Commutators in Rearrangement Invariant Banach and Quasi-Banach Spaces

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Acta Mathematica Sinica,English Series 2023年第7期39卷 1389-1413页

作者： Jia Wei TAN qing Ying xue School of Mathematical Sciences Beijing Normal UniversityLaboratory of Mathematics and Complex SystemsMinistry of EducationBeijing 100875China

In order to study the boundedness of some operators in general function spaces which include Lorentz spaces and Orlicz spaces as special examples,Lorentz introduced a new space called rearrangement invariant Banach function spaces,denoted by *** is shown in this paper that variation operators of singular integrals and their commutators are bounded on RIBFS whenever the kernels satisfy the L~r-H?rmander ***,we obtain some quantitative weighted bounds in the quasi-Banach spaces and modular inequalities for above variation operators and their commutators.

关键词： Variation operators singular integrals commutators sparse operators rearrangement invariant Banach function spaces

Mathematical model of the direct reduction of dust composite pellets containing zinc and iron

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International Journal of Minerals,Metallurgy and Materials 2013年第7期20卷 627-635页

作者： Xiu-wei An Jing-song Wang xue-feng She qing-guo xue State Key Laboratory of Advanced Metallurgy University of Science and Technology Beijing School of Metallurgical and Ecological Engineering University of Science and Technology Beijing School of Mechanical Engineering University of Science and Technology Beijing

Direct reduction of dust composite pellets containing zinc and iron was examined by simulating the conditions of actual production process of a rotary hearth furnace （RHF） in laboratory. A mathematical model was constructed to study the reduction kinetics of iron oxides and ZnO in the dust composite pellets. It was validated by comparing the calculated values with experimental results. The effects of furnace temperature, pellet radius, and pellet porosity on the reduction were investigated by the model. It is shown that furnace temperature has obvious influence on both of the reduction of iron oxides and ZnO, but the influence of pellet radius and porosity is much smaller. Model calculations suggest that both of the reduction of iron oxides and ZnO are under mixed control with interface reactions and Boudouard reaction in the early stage, but only with interface reactions in the later stage.

关键词： rotary hearth furnaces dust zinc ore pellets direct reduction process mathematical models kinetics

Reduction–melting behaviors of boron-bearing iron concentrate/carbon composite pellets with addition of CaO

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International Journal of Minerals,Metallurgy and Materials 2015年第9期22卷 926-932页

作者： Guang Wang qing-guo xue xue-feng She Jing-song Wang State Key Laboratory of Advanced Metallurgy University of Science and Technology Beijing

Although the total amount of boron resources in China is high, the grades of these resources are low. The authors have already proposed a new comprehensive utilization process of boron-bearing iron concentrate based on the iron nugget process. The present work describes a further optimization of the conditions used in the previous study. The effects of CaO on the reduction-melting behavior and properties of the boron-rich slag are presented. CaO improved the reduction of boron-bearing iron concentrate/carbon composite pellets when its content was less than lwt%. Melting separation of the composite pellets became difficult with the CaO content increased. The sulfur content of the iron nugget gradually decreased from 0.16wt% to 0.046wt% as the CaO content of the pellets increased from 1wt% to 5wt%. CaO negatively affected the iron yield and boron extraction efficiency of the boron-rich slag. The mineral phase evolution of the boron-rich slag during the reduction-melting separation of the composite pellets with added CaO was also deduced.

关键词： iron concentrate boron ore reduction composite pellets calcium oxide