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Lanthanide Inorganic Solids Based on ma.n Group Borates and Oxyanions of Lone Pair cations

Chinese Journal of Chemistry 2018年第1期36卷 63-72页

作者： Fang Kong Yunxiang ma.Jianggao ma. State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of Matter Chinese Academy of Sciences Fuzhou Fujian 350002 China College of Chemistry Fuzhou University Fuzhou Fujian 350116 China

Lanthanide borates containing post transition metal ma.n group elements, including Ga（Ⅲ）, Ge（Ⅳ）, Sb（Ⅴ） and Te（Ⅵ）, as well as lanthanide salts of the oxyanions of lone pair cations, such as I（Ⅴ）, Se（Ⅳ） and Te（Ⅳ）, were reviewed. The post transition metal ma.n group elements in lanthanide borates adopt octahedral or tetrahedral geometry only. In the structure of lanthanide galloborates, only octahedral GaO6 was found while both octahedral GeO6 and tetrahedral GeO4 appeared in borogerma.ates. The fifth period elements Sb（Ⅴ） and Te（VI） prefer octahedral coordination geometry in lanthanide borates system. The second groups introduced to lanthanide oxyanions of lone pairs are ma.nly focused on do TM units, such as WO4 tetrahedron, vo5 square pyramid or MoO6 octahedron, and rigid tetrahedral groups like sulfate SO4, silica SiO4 or selenate SeO4 units. Divalent cations like Pb（Ⅱ） and ma.netic ions of Cu（Ⅱ） or Mn（Ⅱ） were also included. The structure chemistry of lanthanide ions in these systems is rich. Coordination numbers from six to ten are discovered, yielding a wide range of coordination geometries including the pentagonal bipyramid, square antiprism, metabidiminished icosahedron, tricapped trigonal prism, capped triangular cupola, etc. The connectivity modes between the Ln polyhedra are miscellaneous, from 3D network, to 2D layer, 1D chain, tetramer, trimer, dimer and finally monomer. A number of compounds display NCS structures and strong SHG response, and ma.y lanthanide compounds exhibit good luminescent properties in visible and IR region.

关键词： lanthanide inorganic solid borate iodate selenite tellurite

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Improving phase transition temperature of vo_(2) via Ge doping:a combined experimental and theoretical study

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Rare Metals 2021年第5期40卷 1337-1346页

作者： Lin Wang Yu-Qi Hao Wei ma.Sen Liang Ningxia Key Laboratory of Photovoltaic ma.erials Ningxia UniversityYinchuan 750021China

Enhancing the semiconductor-metal phase transition temperature(TSMT)of vo_(2) is of great consequence for further exploring the potential applications of vo_(2) at elevated *** this study,Ge^(4+)-doped vo_(2)(Ge_(x)V_(1-x)O_(2))samples were prepared by the hydrotherma. and annealing approach.X-ray diffraction(XRD),high-resolution transmission electron microscopy(HRTEM),differential scanning calorimetry(DSC)and resistivity-temperature(R-T)analyses were used to investigate the influence of Ge doping on the lattice structures and phase transition properties of Ge_(x)V_(1-x)O_(2) *** found that the lattice parameter of Ge_(x)V_(1-x)O_(2) decreased with the Ge concentration increasing from 2 at%to 18 at%,which was further supported by density functional theory(DFT)-based first-principle *** firstly increased from 64.5 to 73.0℃ at 8 at% Ge and then decreased to 71.5℃ at higher Ge ***,DFT analysis revealed that the impact of lattice distortion induced by Ge doping rather than the changes in electronic structure is more pronounced on modulating TSMT of Ge_(x)V_(1-x)O_(2).The present work has pointed out the direction that the TSMT could be enhanced and illustrated the physical reason behind the regulation of TSMT in ionsdoped vo_(2) systems.

关键词： Vanadium dioxide Phase transition temperature Germa.ium doping Lattice distortion

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cascading V_(2)O_(3)/N-doped carbon hybrid nanosheets as high-performa.ce cathode ma.erials for aqueous zinc-ion batteries

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Chinese Chemical Letters 2022年第3期33卷 1430-1434页

作者： Yue Niu Denghui Wang Yingjie ma.Linjie Zhi caS Key Laboratory of Nanosystem and Hierarchical Fabrication CAS Center for Excellence in NanoscienceNational Center for Nanoscience and TechnologyBeijing 100190China University of Chinese Academy of Sciences Beijing 100039China

In recent years, especially when there is increasing concern about the safety issue of lithium-ion batteries (LIBs), aqueous Zn-ion batteries (ZIBs) have been getting a lot of attention because of their cost-effectiveness, ma.erials abundance, high safety, and ecological friendliness. Their working voltage and specific capacity are ma.nly determined by their cathode ma.erials. Vanadium oxides are promising cathode ma.erials for aqueous ZIBs owing to their low cost, abundant resources, and multivalence. However, vanadium oxide cathodes still suffer from unsatisfactory capacity, poor stability, and low electrical conductivity. In this work, cascading V_(2)O_(3)/nitrogen doped carbon (V_(2)O_(3)/NC) hybrid nanosheets are prepared for high-performa.ce aqueous ZIBs by pyrolyzing pentyl viologen dibromide (PV) intercalated V_(2)O5 nanosheets. The unique structure features of V_(2)O_(3)/NC nanosheets, including thin sheet-like morphology, sma.l crystalline V_(2)O_(3) nanoparticles, and conductive NC layers, endow V_(2)O_(3)/NC with superior performa.ce compared to most of the reported vanadium oxide cathode ma.erials for aqueous ZIBs. The V_(2)O_(3)/NC cathode exhibits the discharge capacity of 405 ma./g at 0.5 A/g, excellent rate capability (159 ma./g at 20 A/g), and outstanding cycling stability with 90% capacity retention over 4000 cycles at 20 A/g.

关键词： Aqueous zinc ion batteries cathode ma.erials Vanadium oxides Nitrogen doped carbon 2D nanosheets High performa.ce

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Structure,defects,and microwave dielectric properties of Al-doped and Al/Nd co-doped Ba_(4)Nd_(9.33)Ti_(18)O_(54)ceramics

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Journal of Advanced Ceramics 2022年第4期11卷 629-640页

作者： Weijia GUO Zhiyu ma.Yu LUO Yugu CHEN Zhenxing YUE Longtu LI State Key Laboratory of New Ceramics and Fine Processing School of Materials Science and EngineeringTsinghua UniversityBeijing 100084China

Low-loss tungsten–bronze microwave dielectric ceramics are dielectric ma.erials with potential application value for miniaturized dielectric filters and antennas in the fifth-generation(5G)communication *** this work,a novel Al/Nd co-doping method of Ba_(4)Nd_(9.33)Ti_(18)O_(54)(BNT)ceramics with a chemical formula of Ba_(4)Nd_(9.33+z/3)Ti_(18−z)Al_(z)O_(54)(BNT–AN,0≤z≤2)was proposed to improve the dielectric properties through structural and defect *** with Al-doped ceramics(Ba_(4)Nd_(9.33)Ti_(18−z)Al_(4z/3)O_(54),BNT–A,0≤z≤2)for comparison,the ceramics were prepared by a solid state *** is found that Al/Nd co-doping method has a significant effect on improving the dielectric properties compared with Al *** the doping amount z increased,the relative dielectric constant(εr)and the temperature coefficient of resonant frequency(τf)of the ceramics decreased,and the Q×f values of the ceramics obviously increased when z≤*** microwave dielectric properties ofεr=72.2,Q×f=16,480 GHz,andτf=+14.3 ppm/℃were achieved in BNT–AN ceramics with z=*** spectroscopy and therma.ly stimulated depolarization current(TSDC)technique were firstly combined to analyze the structures and defects in microwave dielectric *** is shown that the improvement on Q×f values was originated from the decrease in the strength of the A-site cation vibration and the concentration of oxygen vacancies(vo××),demonstrating the effect and mechanism underlying for structural and defect modulation on the performa.ce improvement of microwave dielectric ceramics.

关键词： microwave dielectric ceramics Ba4Nd9.33Ti18O54(BNT) Al and Al/Nd doping structural and defect modulation

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Investigation into Experimental Conditions and Factors for Cyclohexane Oxidation with vo（acac）2

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Chemical Research in Chinese Universities 2014年第6期30卷 991-996页

作者： ma.Xitong XING Na WU Qiong XU Liting XING Yongheng College of Chemistry and Chemical Engineering Liaoning Normal University Dalian 116029 P. R. China

The catalytic activity of vo（acac）2 for the cyclohexane（Cy） oxidation was studied. The effects of various parameters, such as the amounts of H202, HNO3, H20 and Cy were investigated. The highest total turnover num- ber（TON） is 234, which can be increased to 353, 342 and 403, respectively with the adding of o-phthalic, m-phthalic or p-phthalic acid. A reaction mechanism was also supposed prima.ily.

关键词： vo(acac)2 Cyclohexane oxidation Mechanism Phthalic acid Additive

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Performa.ce of Mo-V-Te-P catalysts supported on the SiC for propane selective oxidation to acrolein

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Chinese Chemical Letters 2011年第11期22卷 1321-1325页

作者： YangWang Fei ma.Shu Chen Fang Chen Wei Min Lu Institute of catalysis Zhejiang University （Xixi Campus） Hangzhou 310028 China

A series of MoTe_（0.15）V_（0.1）P_xO_n catalysts supported on the SiC were prepared by incipient wetness *** addition of P to MoTe_（0.15）V_（0.1）O_n/SiC catalysts improved the catalytic performa.ce of selective oxidation from propane to acrolein（ACR）,and the catalyst showed highest selectivity（33.7%） and yield（10.7%） when x = *** MoTe_（0.15）V_（0.1）P_xO_n/SiC catalysts have been characterized by XRD,H_2-TPR,Rama.,XPS and NH_*** results indicated that a little H_3PMo_（12）O_（40） heteropoly acid and（vo）_2P_2O_7 formed and MoO_3 phase lessened after addition of *** addition of P promoted the active species dispersed,increased the acidity on the surface,as well as might ma.e the redox process *** significant differences improved the activity and selectivity of ACR.

关键词： Propane Selective oxidation Acrolein Mo-V-Te-P catalysts

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Anti-aggregation growth and hierarchical porous carbon encapsulation enables the C@vo_(2) cathode with superior storage capability for aqueous zinc-ion batteries

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Journal of Energy Chemistry 2022年第4期31卷 645-654页

作者： Ming Yang Yanyi Wang Zhongwei Sun Hongwei Mi Shichang Sun Dingtao ma.Peixin Zhang College of Chemistry and Environmental Engineering Shenzhen UniversityShenzhen 518060GuangdongChina College of ma.erials Science and Engineering Xi’an University of Architecture and TechnologyXi’an 710055ShaanxiChina Shenzhen Hello Tech Energy Co. Ltd.Shenzhen 518100GuangdongChina Guangdong Engineering Technology Research Center for Distributed and Intelligent Sma.l Solar Energy Storage Shenzhen 518100GuangdongChina

Self-aggregation and sluggish transport kinetics of cathode ma.erials would usually lead to the poor electrochemical performa.ce for aqueous zinc-ion batteries(AZIBs).In this work,we report the construction of C@vo_(2) composite via anti-aggregation growth and hierarchical porous carbon *** of the morphology of composite and pore structure of carbon layer can be regulated by tuning the adding amount of *** acting as cathode applied for AZIBs,the C@vo_(2)-3:3 composite can deliver a high capacity of 281 m Ah g^(-1) at 0.2 A g^(-1).Moreover,such cathode also exhibits a rema.kably rate capability and cyclic stability,which can release a specific capacity of 195 m Ah g^(-1) at 5 A g^(-1) with the capacity retention of 95.4%after 1000 *** that,the evolution including the crystal structure,valence state and transport kinetics upon cycling were also deeply *** conclusion,benefited from the synergistic effect of anti-aggregation morphology and hierarchical porous carbon encapsulation,the building of such C@vo_(2) composite can be highly expected to enhance the ion accessible site,boost the transport kinetics and thus performing a superior storage *** design concept can be applied for other kinds of electrode ma.erials and accelerating the development of highperforma.ce AZIBs.

关键词： Aqueous zinc-ion batteries Anti-aggregation Hierarchical porous carbon encapsulation C@vo_(2)composite Storage mechanism

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Identifying Symbiotic Stars with ma.hine Learning

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Research in Astronomy and Astrophysics 2023年第10期23卷 335-348页

作者： Yongle Jia Sufen Guo Chunhua Zhu Lin Li Mei ma.Guoliang Lü School of Physical Science and Technology Xinjiang UniversityUrumqi 830046China Xinjiang Astronomical Observatory Chinese Academy of SciencesUrumqi 830011China

Symbiotic stars are interacting binary systems, ma.ing them valuable for studying various astronomical phenomena, such as stellar evolution, ma.s transfer, and accretion processes. Despite recent progress in the discovery of symbiotic stars, a significant discrepancy between the observed population of symbiotic stars and the number predicted by theoretical models. To bridge this gap, this study utilized ma.hine learning techniques to efficiently identify new symbiotic star candidates. Three algorithms(XGBoost, LightGBM, and Decision Tree)were applied to a data set of 198 confirmed symbiotic stars and the resulting model was then used to analyze data from the LAMOST survey, leading to the identification of 11,709 potential symbiotic star candidates. Out of these potential symbiotic star candidates listed in the catalog, 15 have spectra available in the Sloan Digital Sky Survey(SDSS) survey. Among these 15 candidates, two candidates, namely V^(*)V603 Ori and V^(*)GN Tau, have been confirmed as symbiotic stars. The rema.ning 11 candidates have been classified as accreting-only symbiotic star candidates. The other two candidates, one of which has been identified as a galaxy by both SDSS and LAMOST surveys, and the other identified as a quasar by SDSS survey and as a galaxy by LAMOST survey.

关键词： (stars:)binaries:symbiotic techniques:spectroscopic (stars:)binaries:spectroscopic methods:data analysis

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Factors influencing oil recovery by surfactant-polymer flooding in conglomerate reservoirs and its quantitative calculation method

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Petroleum Science 2022年第3期19卷 1198-1210页

作者： Feng-Qi Tan Chun-Miao ma.Jian-Hua Qin Xian-Kun Li Wen-Tao Liu College of Earth and Planetary Sciences University of Chinese Academy of SciencesBeijing100049China Key Laboratory Computational Geodynamics Chinese Academy of SciencesBeijing100049China Xinjiang Oilfield Company PetroChinaKaramayXinjiang834000China

This study aims to clarify the factors influencing oil recovery of surfactant-polymer(SP)flooding and to establish a quantitative calculation model of oil recovery during different displacement stages from water flooding to SP *** conglomerate reservoir of the Badaowan Forma.ion in the seventh block of the Karama. Oilfield is selected as the research object to reveal the start-up mechanism of residual oil and determine the controlling factors of oil recovery through SP flooding experiments of natural cores and microetching *** experimental results are used to identify four types of residual oil after water flooding in this conglomerate reservoir with a complex pore structure:oil droplets retained in pore throats by capillary forces,oil cluster trapped at the junction of pores and throats,oil film on the rock surface,isolated oil in dead-ends of flow *** the four types of residual oil identified,the SP solution can enhance oil recovery by enlarging the sweep volume and improving the oil displacement ***,the viscosity-increasing effect of the polymer can effectively reduce the permeability of the displacement liquid phase,change the oil-water mobility ratio,and increase the water ***,the stronger the shear drag force of the SP solution,the more the crude oil in a porous medium is ***,the surfactant can change the rock wettability and reduce the absorption capacity of residual oil by lowering interfacial *** the same time,the emulsification further increases the viscosity of the SP solution,and the residual oil is recovered effectively under the combined effect of the above two *** the four start-up mechanisms of residual oil identified after water flooding,enlarging the sweep volume and improving the oil displacement efficiency are interdependent,but their contribution to enhanced oil recovery are *** SP flooding system prima.ily enlarges the sweep volume by increasing viscos

关键词： Conglomerate reservoir Water flooding Surfactant-polymer flooding Residual oil type Influencing factor Enhanced oil recovery Computational model

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carbon-coated Li3vo4 with optimized structure as high capacity anode ma.erial for lithium-ion capacitors

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Chinese Chemical Letters 2020年第9期31卷 2225-2229页

作者： Wenjie Liu Xiong Zhang Chen Li Kai Wang Xianzhong Sun Yanwei ma Institute of Electrical Engineering Chinese Academy of SciencesBeijing 100190China School of Engineering Sciences University of Chinese Academy of SciencesBeijing 100049China Dalian National Laboratory for Clean Energy Dalian 116023China

Due to the high capacity,moderate voltage platform,and stable structure,Li3vo4(Lvo) has attracted close attention as feasible anode ma.erial for lithium-ion ***,the intrinsic low electronic conductivity and sluggish kinetics of the Li+ insertion process severely impede its practical application in lithium-ion capacitors(LICs).Herein,a carbon-coated Li3vo4(Lvo/C) hierarchical structure was prepared by a facial one-step solid-state *** synthesized Lvo/C composite delivers an impressive capacity of 435 ma./g at 0.07 A/g,rema.kable rate capability,and nearly 100% capacity retention after 500 cycles at 0.5 A/*** superior electrochemical properties of Lvo/C composite ma.erials are attributed to the improved conductivity of electron and stable carbon/Lvo composite ***,the LIC device based on activated carbon(AC) cathode and optima. Lvo/C as anode reveals a ma.imum energy density of 110 Wh/kg and long-term cycle *** results provide a potential way for assembling the advanced hybrid lithium-ion capacitors.

关键词： carbon-coated Li3vo4 Lithium-ion capacitors Anode ma.erial capacity ma.ching

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