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Discovery of a new family member of arsenic–vanadium polyoxometalates with high catalytic performance for one-pot coupling of CO2, epoxides and amines

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Tungsten 2025年第1期7卷 80-87页

作者： Fang-Qian wang Yin Zhang Wei-Wei wang mei-Qian Fu Hong-Bing Mo Wei-Dong Yu Chao liu jun Yan College of Chemistry and Chemical Engineering Central South University junior Education Department Changsha Normal University School of Science Hunan University of Technology and Business

Arsenic-vanadium polyoxometalates（POMs） represent a family of tremendous potential catalysts owing to their peculiar physical and chemical *** in CO2conversion,using POMs to catalyze the conversion of CO2and epoxide into chemical intermediates is the research ***,A new family number of arsenic-vanadium POMs,[N（CH3）4]4[As8V12O38（H2O）]·2H2O({As8V12O38}),was reported and characterized by single-crystal X-ray diffraction,fourier transform infrared spectroscopy,X-ray photoelectron spectroscopy,*** from other allotropicity,{As8V12O38}shows a different structure pattern with an I-43d *** obtained {As8V12O38} was employed as a catalyst for the *** initial catalytic reaction confirmed that {As8V12O38} can catalyze the formation of epoxy carbonate by using 1.01 kPa CO2and epoxide at 70℃.Furtherly,when added amine in the catalytic system,oxazolidinone could be obtained by high yields,which provides an efficient way to convert CO2into profitable ***,a possible catalytic reaction mechanism was proposed by using different characterization analyses.{As8V12O38} first catalyzes the epoxide and CO2to form an epoxy carbonate and then catalyzes epoxy carbonate and benzylamine into oxazolidinone.

关键词： Arsenic CO2 conversion Oxazolidinone Polyoxometalates Vanadium

Theoretical analysis and numerical simulation of acoustic waves in gas hydrate-bearing sediments

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Chinese Physics B 2021年第2期30卷 344-354页

作者： Lin liu xiu-mei Zhang xiu-Ming wang State Key Laboratory of Acoustics Institute of AcousticsChinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100149China Beijing Engineering Research Center of Sea Deep Drilling and Exploration Institute of AcousticsChinese Academy of SciencesBeijing 100190China

Based on Carcione-Leclaire model,the time-splitting high-order staggered-grid finite-difference algorithm is proposed and constructed for understanding wave propagation mechanisms in gas hydrate-bearing *** compressional waves and two shear waves,as well as their energy distributions are investigated in *** particular,the influences of the friction coefficient between solid grains and gas hydrate and the viscosity of pore fluid on wave propagation are *** results show that our proposed numerical simulation algorithm proposed in this paper can effectively solve the problem of stiffness in the velocity-stress equations and suppress the grid dispersion,resulting in higher accuracy compared with the result of the Fourier pseudospectral method used by *** excitation mechanisms of the five wave modes are clearly revealed by the results of ***,it is pointed that,the wave diffusion of the second kind of compressional and shear waves is influenced by the friction coefficient between solid grains and gas hydrate,while the diffusion of the third compressional wave is controlled by the fluid ***,two fluid-solid(gas-hydrate formation)models are constructed to study the mode conversion of various *** results show that the reflection,transmission,and transformation of various waves occur on the interface,forming a very complicated wave field,and the energy distribution of various converted waves in different phases is *** is demonstrated from our studies that,the unconventional waves,such as the second and third kinds of compressional waves may be converted into conventional waves on an *** propagation mechanisms provide a concrete wave attenuation explanation in inhomogeneous media.

关键词： gas hydrate-bearing sediments Carcione-Leclaire model time-splitting staggered-grid finite-difference slow-wave characteristics

Multifunctional robust aerogel separator towards high-temperature,large-rate,long-cycle lithium-ion batteries

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Chinese Chemical Letters 2023年第5期34卷 530-534页

作者： mei-Chen liu Hui-jun Chen Gang Wu xiu-Li wang Yu-Zhong wang The Collaborative Innovation Center for Eco-Friendly and Fire-Safety Polymeric Materials(MoE) National Engineering Laboratory of Eco-Friendly Polymeric Materials(Sichuan)State Key Laboratory of Polymer Materials EngineeringCollege of ChemistrySichuan UniversityChengdu 610064China

Separators is indispensable for the normal operation of lithium-ion batteries(LIBs).However,the widely used commercial polyolefin separators have some inherent deficiencies such as poor thermotolerance,high inflammability and inferior electrolyte wettability,which restrict their further applications of the advanced and safe ***,we design a novel thermotolerant(a shrinkage percentage of 0%at 300℃)and flame retarded aerogel separator consisting of aramid nanofibers(ANFs).Because of its high porosity(86.5%±6.1%)and excellent electrolyte uptake(695%),the ANFs aerogel separator has an ionic conductivity of 1.04 mS/cm and a high lithium-ion transference number(0.67),which can endow LIBs with outstanding rate performance and superior cycling ***,the ANFs aerogel separator-based batteries possess a discharge specific capacity of 102 m Ah/g with a capacity retention of 90.7%and a Coulombic efficiency of 99.3%after 600 cycles at 5 *** addition,under an operated temperature of 90℃,the battery with ANFs aerogel separator can still conduct the very steady chargedischarge,presenting a capacity retention of 90.1%and a Coulombic efficiency of 99.6%after 200 cycles at 3 ***,the separator can probably serve as a potential candidate for application to advanced and safe LIBs.

关键词： Aramid nanofibers Aerogel separator Lithium-ion batteries High performance Safety

An Integrative Analysis of the Effects of Auxin on Jasmonic Acid Biosynthesis in Arabidopsis thaliana

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Journal of Integrative Plant Biology 2006年第1期48卷 99-103页

作者： jun liu xiu-Jie wang Institute of Genetics and Development Biology the Chinese Academy of Sciences Beijing 100101 China

Auxin and jasmonic acid （JA） are two plant phytohormones that both participate in the regulation of many developmental processes. Jasmonic acid also plays important roles in plant stress response reactions. Although extensive investigations have been undertaken to study the biological functions of auxin and JA, little attention has been paid to the cross-talk between their regulated pathways. In the few available reports examining the effects of auxin on the expression of JA or JA-responsive genes, both synergetic and antagonistic results have been found. To further investigate the relationship between auxin and JA, we adopted an integrative method that combines microarray expression data with pathway information to study the behavior of the JA biosynthesis pathway under auxin treatment. Our results showed an overall downregulation of genes involved in JA biosynthesis, providing the first report of a relationship between auxin and the JA synthesis pathway in Arabidopsis seedlings.

关键词： Arabidopsis auxin biosynthesis jasmonic acid pathway.

Enhanced biological nutrients removal using an integrated oxidation ditch with vertical circle from wastewater by adding an anaerobic column

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Journal of Environmental Sciences 2005年第6期17卷 894-898页

作者： wang Shu-mei liu jun-xin Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China

Compared to conventional oxidation ditches, an integrated oxidation ditch with vertical circle （IODVC） has the characters of concise configuration, simple operation and maintenance, land saving and automatical sludge returning. By the utilization of vertical circulation, an aerobic zone and an anoxic zone can be unaffectedly formed in the IODVC. Therefore, COD and nitrogen can be efficiently removed. However, the removal efficiency of phosphorus was low in the IODVC. In the experiment described, a laboratory scale system to add an anaerobic column to the IODVC has been tested to investigate the removal of phosphorus from wastewater. The experimental results showed that the removal efficiency of TP with the anaerobic column was increased to 54.0% from 22.3% without the anaerobic column. After the acetic sodium was added into the influent as carbon sources, the mean TP removal efficency of 77. 5 % was obtained. At the same time, the mean removal efficiencies of COD, TN and NH3-N were 92.2%, 81.6% and 98.1%, respectively, at 12 h of HRT and 21-25 d of SRT. The optimal operational conditions in this study were as follows： recycle rate = 1.5-2.0, COD/TN 〉 6, COD/TP 〉 40, COD loading rate = 0.26-0.32 kgCOD/（kgSS· d）, TN loading rate = 0. 028-0. 034 kgTN/（ kgSS·d） and TP loading rate = 0.003-0.005 kgTP/（kgSS· d）, respectively.

关键词： integrative oxidation ditch with vertical circle wastewater treatment biological nutrient removal

Microstructure,wetting property of Sn-Ag-Cu-Bi-xCe solder and IMC growth at solder/Cu interface during thermal cycling

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Rare Metals 2021年第3期40卷 714-719页

作者： Yuan wang xiu-Chen Zhao Ying liu Yong wang Dong-mei Li School of Materials Science and Engineering Beijing Institute of TechnologyBeijing 100081China Center of Packaging and Testing Beijing Microelectronics Technology InstituteBeijing 100076China

The effects of adding small amounts of cerium(Ce) to Sn-3.3 Ag-0.2 Cu-4.7 Bi solder on microstructure,wettability characteristic,interfacial morphology and the growth of interfacial intermetallic compound(IMC) during thermal cycling were investigated by optical microscopy(OM),scanning electron microscopy(SEM) and solderability *** is found that the p-Sn phase,Ag_(3)Sn phase and Cu6 Sn5 phase in the solder are refined and the wetting force *** is an active element;it more easily accumulates at the solder/flux interface in the molten state,which decreases the interfacial surface energy and reduces the driving force for IMC formation on Cu substrate;therefore,the thickness of IMC at the solder/Cu interface decreases when appropriate Ce was added into the ***,the Ce-containing solders have lower growth rate of interfacial IMC than solders without Ce during the thermal cycling between-55 and 125℃.When the Ce content is 0.03 wt% in the Sn-3.3 Ag-0.2 Cu-4.7 Bi solder,the solder has the best wettability and the minimum growth rate of interfacial IMC layer.

关键词： Lead-free solder Rare earth element Microstructure Wettability Intermetallic compound Thermal cycling

Maximizing ionic transport of Li1+xAlxTi2-xP3O12 electrolytes for all-solid-state lithium-ion storage:A theoretical study

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Journal of Materials Science & Technology 2021年第14期73卷 45-51页

作者： Tiantian wang jun mei Jianjun liu Ting Liao State Key Laboratory of High Performance Ceramics and Superfine Microstructure Shanghai Institute of CeramicsChinese Academy of Sciences1295 Dingxi RoadShanghai 200050China School of Mechanical Medical and Process EngineeringQueensland University of Technology2 George StreetBrisbaneQLD4000Australia School of Chemistry and Physics Queensland University of Technology2 George StreetBrisbaneQLD4000Australia Centre of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100049China Centre for Materials Science Queensland University of Technology2 George SfreefBrisbane.QLD4000Australia

The concept of all-solid-state batteries provides an efficient solution towards highly safe and long-life energy storage,while the electrolyte-related challenges impede their practical ***1+xAlxTi2-xP3O12(0≤x≤1)with superior Li ionic conductivity holds the promise as an ideal solidstate *** intrinsic mechanism to reach the most optimum ionic conductivity in Al-doped Li1+xAlxTi2-xP3O12,however,is unclear to ***,this work intends to provide an atomic scale study on the Li-ion transport in Li1+xAlxTi2-xP3O12electrolyte to rationalize how Al-dopant initiates interstitial Li activity and facilitate their easy mobility combining Density Functional Theory(DFT)and ab initio Molecular dynamics(AIMD)*** is discovered that the interstitial Li ions introduced by Al dopants can effectively activate the neighboring occupied intrinsic Li-ions to induce a long-range mobility in the lattice and the maximum Li ionic conductivity is achieved at 0.50 Al doping *** Li-ion migration paths in Li1+xAlxTi2-xP3O12have investigated as the degree of distortion of[PO4]tetrahedra and[TiO6]octahedra resulted by different Al doping *** asymmetry of the surrounding distorted[PO4]and[TiO6]polyhedrons play a critical role in reducing the migration barrier of Li ions in Li1+*** flexible[Ti O6]polyhedrons with a capacity to accommodate the structural distortion govern the Li ionic conductivity in Li1+*** work rationalizes the mechanism for the most optimum Li ionic conductivity in Al-doped Li Ti2P3O12electrolyte and,more importantly,paves a road for exploring novel all-solid-state lithium battery electrolytes.

关键词： Density Functional Theory Solid-state-electrolyte Li ionic conductivity Bond angle variance Al-dopant

Vapour-phase O-methylation of Catechol with Methanol on Ti-containing Phosphate Catalysts

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Chemical Research in Chinese Universities 2006年第4期22卷 533-536页

作者： ZHU Xiao-mei LI Xue-mei liu Gang ZOU xiu-jing wang Yan-li JIA Ming-jun ZHANG Wen-xiang College of Chemistry Jilin University Changchun 130021 P. R. China Shanghai Huayi Acrylic Acid Co. Ltd. Shanghai 200137 P. R. China

Ti-containing phosphate（ Ti-P-O ） catalysts with different molar ratios of P to Ti （0--2. 0 ） were synthesized and characterized by XRD, N2-adsorption/desorption, IR and temperature-programmed desorption （TPD） methods. The catalytic properties of Ti-P-O samples in the vapor-phase O-methylation of catechol with methanol were also studied. The catechol conversion increases with the increase of the molar ratio of P to Ti in a range of 0-0. 33, while a further increase in the P content leads to a decrease of the catalytic activity. Meanwhile, the selectivities of the catalysts to the main product（guaiacol） increase gradually with the increase of the molar ratio of P to Ti. The presence of relatively strong Lewis acidic and/or basic sites in the P-free catalyst should be responsible for the formation of C-alkylation products. The weak acid-base characteristics of the catalysts are favourable for the mono-O-methylation of catechol. In comparison with the Lewis acidic sites, the Bronsted acidic sites on the catalysts are more active for the title reaction.

关键词： Phosphates Acid-base catalysis Guaiacol Catechol O-Methylation

W-Grbner basis and monomial ideals under polynomial composition

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Applied Mathematics(A Journal of Chinese Universities) 2011年第3期26卷 287-294页

作者： LI Dong-mei liu Jin-wang liu Wei-jun School of Mathematical Sciences and Computing Technology Central South University Changsha410075 China School of Mathematics and Computing Sciences Hunan University of Science and Technology Xiangtan 411201 China

The notion of weakly relatively prime and W-Gr6bner basis in K[x1, x2,…, xn] are given. The following results are obtained： for polynomials fl, f2, ..., fm, {f1^λ1, f2^λ2,…, fm^λm} is a GrSbner basis if and only if f1, f2, …, fm are pairwise weakly relatively prime with λ1, λ2, …, λm arbitrary non-negative integers; polynomial composition by θ = （θ1,θ2, …, θn） commutes with monomial-Grobner bases computation if and only if θ1, θ2, , θm are pairwise weakly relatively prime.

关键词： W-Grobner basis weakly relatively prime polynomial composition.