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A Positive Solution for Some Critical p-Laplacian Systems

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Acta Mathematica Sinica,English Series 2015年第3期31卷 479-500页

作者： Xiao Zhi wang College of Science University of Shanghai for Science and Technology

This paper deals with the existence of a positive solution for two classes of critical quasilinear system. We prove these results by a variant of mountain pass lemma, combining two convergence theorems and two estimate results. Here we avoid the usual compactness arguments（e.g., Palais-Smale condition or Cerami condition） and reveal the potential of some energy level estimates for the existence of nontrivial solutions.

关键词： p-Laplacian system critical growth convergence theorem estimate result

Microstructures and mechanical properties of Cu/Al compound materials during thermal cycle

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Rare Metals 2022年第11期41卷 3911-3918页

作者： Bing wang Ping Liu Xin-Kuan Liu Zi-Yan wang Yan-Yan wang Xiao-Hong Chen Xiao-Zhi Liu School of Materials Science and Engineering University of Shanghai for Science and TechnologyShanghai200093China Automobiles Science and Technology(Shanghai)Co. LtdShanghai200433China

Cu/Al compound materials,named as copperclad aluminum bus bars,are widely used in heat dissipation of modern *** thermal cycle tests were conducted at 200,250 and 300℃for different cycle times,*** of thermal cycle temperatures and thermal cycle times on micro structures and mechanical properties of the interface were *** results show that the width of bonding layer and bond strength are significantly affected by thermal cycle temperatures and ***,the variety or the quantity of intermediate compounds is scarcely ***_(2)Cu,Cu_(9) Al_(4)and CuAl were identified on the *** the increase in cycle times,grains of the material grew ***,grains of the interface grew up more apparently than those of Cu and *** knowledge may be applied in the establishment of service condition and quality evaluation of material.

关键词： Copper-clad aluminum bus bars Thermal cycle Interface Bonding Microstructure Intermetallic

Characterization and Thermal Conductivity of Modified Graphite/Fatty Acid Eutectic/PMMA Form-Stable Phase Change Material

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Journal of Wuhan University of Technology(Materials Science) 2013年第3期28卷 586-591页

作者：孟多 wang Lijiu School of Civil and Architectural Engineering Liaoning University of Technology Institute of Building Materials Dalian University of Technology

We prepared and characterized a form-stable composite phase change material （PCM） with higher thermal conductivity. Capric acid（CA）-myristic acid（MA） eutectic as core, poly-methyl methacrylate （PMMA） as supportive matrix and modified graphite （MG） powders serving as the thermal conductance improver were blended by bulk- polymerization method. The composite PCMs with different MG mass fraction （2%, 5%, 7%, 10% and 15%） were characterized by FT-IR, SEM, DSC technique and mechanical tests. Thermal conductivities of the composites were measured by transient hot-wire method. The results indicate that MG powders have been successfully inserted into the CA-MA/PMMA matrix without any chemical reaction with each other. The MG/CA-MA/PMMA composites maintain good thermal storage performance while the thermal conductivity has been enhanced significantly. The composite PCM added with 15 wt% MG powders increases approximately as 195.9% in thermal conductivity. Moreover, the thermal conductivity improvement of the composite PCMs is also verified by the melting-freezing experiment, which is profitable for the heat transfer efficiency in latent heat thermal energy storage system.

关键词： form-stable composite PCM fatty acid eutectic poly-methyl methacrylate modified graphite thermal conductivity

p-adic Transcendence and p-adic Transcendence Measures for the Values of Mahler Type Functions

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Acta Mathematica Sinica,English Series 2006年第1期22卷 187-194页

作者： Tian Qin wang Academy of Mathematics and Systems Science Chinese Academy of Sciences Beijing 100080 P. R. China College of Computer Sciences Henan University Kaifeng 475001 P. R. China

We prove the p-adic transcendence and p-adic transcendence measures for the values of some Mahler type functions.

关键词： p-adic transcendence p-adic transcendence measure Mahler type function

Effect of thermodynamic parameters on prediction of phase behavior and process design of extractive distillation

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Chinese Journal of Chemical Engineering 2018年第5期26卷 993-1002页

作者： HuiJia Huixin wang Kang Ma Mengxiao Yu Zhaoyou Zhu Yinglong wang College of Chemical Engineering Qingdao University of Science and Technology Qingdao 266042 China National Registration Center for Chemicals SINOPEC Research Institute of Safety Engineering Qingdao 266071 China

Extractive distillation was investigated for separation of the minimum azeotrope of n-propanol/water, via the Aspen Plus simulation platform. Experimental data of n-propanol/water, which could pass the thermodynamic consistency test, were regressed to get suitable binary interaction parameters(BIPs) by the UNIQUAC thermodynamic model. The azeotrope system was heterogeneous in the simulation with built-in BIPs, which was contrary to the experimental data. The study focused on the effect of thermodynamic parameters on the prediction of phase behavior, and process design of extractive distillation. N-methyl-2-pyrrolidone(NMP) and ethylene glycol were used as solvents to implement the separation. Processes with built-in and regressed BIPs were explored,based on the minimum total annual cost(TAC). There were significant differences in the phase behavior simulation using different thermodynamic parameters, which showed the importance of BIPs in the design and optimization of extractive distillation.

关键词： Extractive distillation Thermodynamic parameters Phase behavior UNIQUAC TAC

A uniqueness theorem for indefinite Sturm-Liouville operators

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Applied Mathematics(A Journal of Chinese Universities) 2012年第3期27卷 345-352页

作者： wang Yu-ping Department of Applied Mathematics Nanjing Forestry UniversityNanjing210037JiangsuChina

In this paper, we discuss the inverse problem for indefinite Sturm-Liouville operators on the finite interval [a, b]. For a fixed index n（n = 0, 1, 2,… ）, given the weight function w（x）, we will show that the spectral sets {λn（q, ha,hk）}＋∞k=1 and {λ-n（q, hb,hk）}＋∞k=1 for distinct hk are sufficient to determine the potential q（x） on the finite interval [a, b] and coefficients ha and hb of the boundary conditions.

关键词： Inverse problem uniqueness theorem indefinite Sturm-Liouville problem eigenvalue.

Volatile and C-H-O isotopic compositions of giant Fe-Ti-V oxide deposits in the Panxi region and their implications for the sources of volatiles and the origin of Fe-Ti oxide ores

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Science China Earth Sciences 2012年第11期55卷 1782-1795页

作者： wang Christina Yan Key Laboratory of Mineralogy and Metallogeny Guangzhou Institute of GeochemistryChinese Academy of SciencesGuangzhou 510640China

The Panzhihua,Hongge,and Baima Fe-Ti-V oxide deposits in the Panzhihua-Xichang(Panxi) region are hosted in large layered mafic-ultramafic *** layered intrusions intrude either the Neoproterozoic Dengying Formation,composed mainly of limestone,or the Paleoproterozoic Hekou Formation,composed of meta-sedimentary-volcanic *** remains unclear if the wall rocks have been involved during the fractionation of magmas and have affected the sequence of crystallization of Fe-Ti *** and their C-H-O isotopic compositions of magnetite,apatite,clinopyroxene,and plagioclase of different types of ores from the three intrusions are analyzed using a technique of stepwise heating mass spectrometer to evaluate the role of wall rocks in the formation of Fe-Ti oxide *** released from magnetite are composed mainly of H 2 O and CO 2,whereas the other minerals are composed mainly of H 2 O,CO 2 and H *** 800-1200°C temperature interval,the average 13 C values of CO 2 of all the minerals from the three intrusions range from 7.7‰ to 13.5‰ and the average 18 O CO 2 values from 19.1‰ to 19.5‰,which are scattered in a mixed field with basalt and the two types of wall rocks as end-members,indicating that CO 2 from the wall rocks may have been involved in the magmas from which the three intrusions *** 400-800 C temperature interval,both 13 C values(13.7‰ to 17.9‰ on the average) and 18 O values(16.2‰ to 19.2‰ on the average) of CO 2 of all the minerals are lower than those for 800-1200 C temperature interval,and much closer to the values of the wall *** H 2 O released at the 400-800 C temperature interval has relatively low D values ranging from 90‰ to 115‰,also indicating the involvement of fluids from the wall *** average bulk contents of volatiles released from magnetite of the Hongge,Baima,and Panzhihua intrusions are 4891,2996,and 1568 mm 3 STP/g,respectively,much higher than those released from other minerals in total,which are 382

关键词： magnetite volatiles C-H-O isotope Fe-Ti-V oxide ore Panxi region

Designed synthesis of chlorine and nitrogen co-doped Ti_(3)C_(2)MXene quantum dots and their outstanding hydroxyl radical scavenging properties

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Journal of Materials Science & Technology 2021年第19期78卷 30-37页

作者： Lin Zhao Zhao wang Yan Li Sen wang Lifeng wang Zhaojun Qi Qiang Ge Xiaoguang Liu Jin Zhong Zhang School of Materials Science and Engineering University of Science and Technology BeijingBeijing100083China Department of Chemistry and Biochemistry University of CaliforniaSanta CruzCalifornia 95064United States

As a novel zero-dimensional(0D)material,metal carbides and/or carbonitrides(MXenes)quantum dots(MQDs)show unique photoluminescence properties and excellent ***,due to the limited synthesis methods and research to date,many new features have yet to be ***,to explore their new properties and expand biological applications,chlorine and nitrogen co-doped Ti_(3)C_(2)MXene quantum dots(Cl,N-Ti_(3)C_(2)MQDs)were designed and synthesized,and their hydroxyl radical scavenging properties were investigated for the first time,revealing outstanding ***,N-Ti_(3)C_(2)MQDs was directly stripped from bulk Ti_(3)Al C_(2)by electrochemical etching,while N and Cl are successfully introduced to carbon skeleton and Ti boundaries in the etching process by electrochemical reactions between selected electrolytes and Ti_(3)C_(2)skeleton,*** obtained Cl,N-Ti_(3)C_(2)MQDs exhibit large surface-to-volume ratio due to small particle size(ca.3.45 nm)and excellent higher scavenging activity(93.3%)and lower usage(12.5μg/m L)towards hydroxyl radicals than the previous reported graphene-based *** underlying mechanism of scavenging activity was also studied based on the reduction experiment with potassium permanganate(KMnO_(4)).The reducing ability of the intrinsic Ti_(3)C_(2)structure and electron donation of double dopants are the main contributors to the outstanding scavenging activity.

关键词： Ti_(3)C_(2)MXene quantum dots Chlorine and nitrogen co-doping Hydroxyl radical Scavenger

Arithmetic Properties of Overpartition Triples

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Acta Mathematica Sinica,English Series 2017年第1期33卷 37-50页

作者： Liu Quan wang Department of Mathematics National University of Singapore Singapore 119076 Singapore

Let P-3 （n） be the number of overpartition triples of n. By elementary series manipulations, we establish some congruences for P-3（n） modulo small powers of 2, such as P-3（16n＋14）≡0 （mod 32）, P-3（8n＋7）≡0 （mod 64）.We also find many arithmetic properties for P-3（n） modulo 7, 9 and 11, involving the following infinite families of Ramanujan-type congruences： for any integers α≥1 and n ≥ 0, we have

关键词： Partitions overpartition triples congruences theta functions