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Chinese Journal of Structural Chemistry 2006年第7期25卷 837-843页

作者： MENG Fan-Xia LIU Kun chen ya-guang Institute of Polyoxometalate Chemistry Faculty of Chemistry Northeast Normal University Changchun 130024 China

An unusual inorganic-organic hybrid hexatungstate complex [Cu（phen）3][W6O19] 1 （C36H24 CuN6O19W6, Mr= 2011.20） was hydrothermally synthesized and characterized by singlecrystal X-ray diffraction, IR spectrum, UV-VIS spectrum and elemental analyses. This compound crystallizes in the monoclinic system, space group C2/c with a = 19.1005（11）, b = 11.2585（11）, c = 20.2867（15） A, β= 102.177（2）°, V= 4264.4 A^ 3, μ（MoKa） = 16.691 mm^-1, Dc = 3.133 g/cm^3, Z = 4, F（000） = 3628, the final R = 0.0338 and wR = 0.0798 for 4090 observed reflections with I 〉 2σ（I）. The result of structure determination shows that the crystal structure is constructed from [W6O19]^2- cluster anions and [Cu（phen）3]^2＋ complex fragments, which are held together into a three-dimensional network through hydrogen-bonding interactions.

关键词： hydrothermal synthesis tungstates polyoxometalates copper coordination complexes

Synthesis, Characterization, and Properties of Supported Tungstozincate Bridged by Co(Ⅱ) Complex Fragment

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Chemical Research in Chinese Universities 2008年第6期24卷 668-671页

作者： LIU Kun LI Jia LIU Hong-bo chen ya-guang Key Laboratory of Polyoxometalates Science of Ministry of Education Northeast Normal University Changchun 130024 P. R. China Department of Pharmaceutics Changchun Medical College Changchun 130031 P. R. China

[Co^11（phen）3]2[{（ZnW12O40）Co^11（phen）2（H2O）}2Co^11（trien）2（NaH2O）2]·3H2O was synthesized via hydrothermal technique and characterized with elemental analyses, IR spectroscopy, TGA-DTA, and variable temperature magnetic susceptibility. The compound crystallized in the monoclinic system with the space group P21/n, a=1.8210 nm, b=2.3592 nm, c=2.2932 nm, β=110.31°, V=9.239 nm^3, Z=2, R1=0.0827. The compound consists of two coordination cations, three lattice water molecules, and a macroanion [{（ZnW12O40）Co（phen）2（H2O）}2Co（C6H18N4）2·（NaH2O）2]^4- in which each supported Keggin anion [（ZnW12O40Co^11（phen）2（H2O）]^4- acts as a ligand to coordinate to central bridging Co^2＋ ion via a terminal oxygen atom. Hydrogen bonds are responsible for the construction of 3D architecture of the compound. The compound is paramagnetic with a weak antiferromagnetic interaction（0=-46.796 K）.

关键词： Hydrothermal synthesis Organic-inorganic hybrid Supported Keggin structure Cobalt complex Tungstozincate

Synthesis,Crystal Structure and Thermal Stability of Homopolytungstate Supporting Nickel(Ⅱ) Coordination Fragments

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Chemical Research in Chinese Universities 2007年第4期23卷 391-394页

作者： LIU Kun MENG Fan-xiaI MA Feng-xia chen ya-guang Key Laboratory of Polyoxometalates Science of Ministry of Education College of Chemistry Northeast Normal University Changchun 130024 P. R. China Basic Science Department Jilin Agricultural Science and Technology College Jilin 132101 P. R. China

The orsano-inorganic hybrid compound [ Ni（phen）3] [ （H2W12O40） { Ni（phen）2H2O} { Ni（trien） } ]·2H2O was synthesized from Na2 WO4·2H2O, NiSO4·6H2O, CH3COOK, triethylenetetramine and 1,10-phenanthroline in water by the hydrothermal reaction, and characterized by IR, X-ray single crystal diffraction, and TG-DTA analysis. This compound crystallized in the monoclinic system, space group P2 （1）/n, with lattice constants： a =1.80998 （6） nm, b =2.36504（8） nm, c =2.29199（7） nm,β= 110.2220（10）°, V=9.2065（5） nm, Z=4. Final R indices R1=0.0532. ωR2=0.1295. The compound is decomposed at 593℃.

关键词： Isopolytungstate Nickel complex Crystal structure Organo-inorganic hybrid Supramolecular architecture Thermal stability

Effect of Glucose-lowering of Heteropolytungstogermanate β-K_6H[GeW_9V_3O_(40)]·9H_2O

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Chemical Research in Chinese Universities 2002年第3期18卷 246-248页

作者： LIU Jing fu LIU Ju tao MA Jian fang chen ya guang LI Cai Department of Chemistry Northeast Normal UniversityChangchun 130024P.R.China Institute of Basic Applied Medicine Jilin UniversityChangchun 130021P.R.China

Preliminary tests in rats have shown that the title complex is an efficient insulin mimic, which may be the first example of polyoxomatalates possessing insulin mimetic activity.

关键词： Heteropolytungstogermanate Insulin mimetic activity Effect of glucose lowering

Enhancing reversible hydrogen storage performance of 2LiBH_(4)–MgH_(2)via in-situ building heterogeneous nucleation sites

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Rare Metals 2024年第9期43卷 4367-4376页

作者： Wei chen ya-Hui Sun Tian Xu Xue-Bin Yu guang-Lin Xia Department of Materials Science Fudan UniversityShanghai 200433China

2LiBH_(4)-MgH_(2)composite is one of the most attractive reactive hydride composites with a theoretic hydrogen capacity of 10.8 wt%.However,the large nucleation restriction of MgB_(2)during the second step of dehydrogenation results in sluggish hydrogen storage kinetics and high operating temperature,which hinders its practical application as on-board hydrogen storage ***,Al3Ti doped Al nanoparticles(AT NPs)are prepared by a facile chemical reduction reaction to improve the hydrogen storage performance of 2LiBH_(4)-MgH_(2)*** the initial H_(2)desorption process,MgAlB_(4)and TiB_(2)that have identical crystal structure and low d-value mismatch with MgB_(2)resulting from the reaction between AT NPs and 2LiBH_(4)-MgH_(2)composite serve as effective nucleation sites for the formation of MgB_(2).As a result,the apparent activation energy of the two-step H_(2)desorption of AT NPs doped 2LiBH_(4)-MgH_(2)composite are notably decreased to(110.0±5.9)and(119.6±1.4)kJ·mol^(-1),which is 55.5 and 33.5 kJ·mol^(-1)lower than that of the undoped *** importantly,a reversible hydrogen storage capacity of 9.2 wt%after 10cycles of H_(2)desorption and adsorption could be achieved,corresponding to a capacity retention rate of 99%.The building of reactive bimetallic catalyst towards in situ formation of heterogeneous nucleation sites provides a new strategy for improving the hydrogen storage performance of reactive hydride composites.

关键词： Reversible hydrogen storage Reactive hydride composites Catalytic effects Heterogeneous nucleation

Research on shell-side heat and mass transfer with multi-component in LNG spiral-wound heat exchanger under sloshing conditions

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Petroleum Science 2024年第2期21卷 1333-1345页

作者： Xue-Ping Du guang-Lei Yu ya-cheng Xu Zhi-Jie chen Nai-Liang Li Huan-guang Wang School of Low-carbon Energy and Power Engineering China University of Mining and TechnologyXuzhou221116JiangsuChina Key Laboratory of Thermo-Fluid Science and Engineering MOEXi'an Jiaotong UniversityXi'an710049ShaanxiChina Xi'an Aerospace Propulsion Test Technology Institute Xi'an710100ShaanxiChina

The spiral-wound heat exchanger(SWHE) is the primary low-temperature heat exchanger for large-scale LNG plants due to its high-pressure resistance, compact structure, and high heat exchange efficiency. This paper studied the shell-side heat and mass transfer characteristics of vapor-liquid two-phase mixed refrigerants in an SWHE by combining a multi-component model in FLUENT software with a customized multicomponent mass transfer model. Besides, the mathematical model under the sloshing condition was obtained through mathematical derivation, and the corresponding UDF code was loaded into FLUENT as the momentum source term. The results under the sloshing conditions were compared with the relevant parameters under the steady-state condition. The shell-side heat and mass transfer characteristics of the SWHE were investigated by adjusting the component ratio and other working conditions. It was found that the sloshing conditions enhance the heat transfer performance and sometimes have insignificant effects. The sloshing condition is beneficial to reduce the flow resistance. The comprehensive performance of multi-component refrigerants has been improved and the improvement is more significant under sloshing conditions, considering both the heat transfer and pressure *** results will provide theoretical support for the research and design of multi-component heat and mass transfer enhancement of LNG SWHE under ocean sloshing conditions.

关键词： Spiral-wound heat exchanger Sloshing conditions Two-phase flow Multi-component Heat and mass transfer

Syntheses and Structure of Potassium α-and β-Trivanadoenneatungstogermanates

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Chemical Research in Chinese Universities 1993年第1期9卷 6-12页

作者： chen ya-guang , QU Lun-yu, PENG Jun and YU Ming (Department of Chemistry, Northeast Normal University, Changchun, 130024)

Potassium α-and β-trivanadoenneatungstogermanates were prepared and characterized by means of elemental analysis, IR, 51V and 183W NMR spectra and polarography. The single crystal structure of a-isomer was determined. The final R is 0. 083. The results show that two prepared heteropoly anions have Keggin structure, and a-isomer belongs to A-type and has stronger oxidizing ability than β-isomer.

关键词： Crystal structure Trisubstituted compound Tungstogermanate

Energy saving analysis for CO_(2)–O_(2)mixed injection technology in converter steelmaking

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Journal of Iron and Steel Research International 2024年第5期31卷 1095-1103页

作者： Bao-chen Han Chun-liang Gao ya-qiang Li Dan Liu guang-sheng Wei Rong Zhu Hebei Key Laboratory of Material Near-Net Forming Technology School of Material Science and EngineeringHebei University of Science and TechnologyShijiazhuang050018HebeiChina Department of Automotive Engineering Hebei Vocational University of Technology and EngineeringXingtai054000HebeiChina School of Metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing100083China

Energy-saving in China's iron and steel industry still relies on the development and improvement of short-term energy saving ***,a special converter smelting technology incorporating energy saving was *** evaluate the energy-saving potential of the CO_(2)–O_(2)mixed injection(COMI)technology,collected production data were used to develop an improved techno-economic *** reveal that the technology can save energy through auxiliary material consumption,sensible heat of solid by-product,iron loss reduction,and energy *** application of COMI technology in an enterprise is cost effective,involving the energy saving potential of 0.206 GJ/t,the cost of conserved energy of−48.83 yuan/GJ,and a simple payback period of 0.35 year for a 60-million-yuan *** analysis shows that the investment cost and discount rate primarily influence the cost of conserved energy of the *** the discount rate increased,the cost of conserved energy also gradually ***,the COMI technology is an energy-saving technology with good development prospects.

关键词： Converter steelmaking COMI technology Energy saving Techno-economic model Investment cost

VECTOR VARIATIONAL INEQUALITY AND ITS APPLICATION FOR MULTIOBJECTIVE OPTIMIZATION

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Chinese Science Bulletin 1989年第12期34卷 969-972页

作者：陈光亚 Institute of Systems Science Academia Sinica Beijing

An important subject of the multiobjective optimization is the problem in which it is desired to find an optimal (satisfied) efficient solution. An approach for this problem shall be concerned with the problem of opti... 详细信息

关键词： vector variational inequality multiobjective optimization optimization over an efficient set.

Highly Improved Creep Resistance in Polypropylene Through Thermally Reduced Graphene Oxide and Its Creep Lifetime Prediction

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Chinese Journal of Polymer Science 2024年第2期42卷 256-266,I0010页

作者： Can-Can Zhang Jun-Long yang ya-Jiang Huang guang-Xian Li College of Polymer Science and Engineering State Key Laboratory of Polymer Materials Engineering of ChinaSichuan UniversityChengdu610065China

Polypropylene(PP) exhibits suboptimal creep resistance due to the presence of methyl groups on its main chain, leading to irregular chain segment distribution, diminished inter-chain interaction, and crystallinity. This structural feature causes chain slippage in PP under stress,significantly constraining its service lifetime. In this study, thermally reduced graphene oxide(TrGO) nanosheets were incorporated into the PP matrix, yielding a nanocomposite with exceptional creep resistance performance. Results demonstrated that at a stress of 25 MPa, a 2.0 wt% TrGO content could enhance the creep failure lifetime of PP by 21.5 times compared to neat PP. Rheology, transmission electron microscopy(TEM),and scanning electron microscopy(SEM) characterization techniques were employed to analyze the mechanism of TrGO's influence on PP's creep behavior. It was observed that when TrGO content exceeded 1.0 wt%, an effective particle network structure formed within the PP matrix. This homogeneously dispersed TrGO-formed particle network structure restricted the migration and rearrangement of PP molecular chains, enabling prolonged stress resistance without structural failure. By combining the time-strain superposition method with the critical failure strain as a criterion, generalized creep compliance curves for PP and its composites were established, facilitating the prediction of material creep failure lifetimes, with a strong agreement between experimental and predicted lifetime values. This research proposes a novel strategy aimed at developing polypropylene materials and products with enhanced long-term stability and durability, thus extending service life, reducing failure risk, and broadening their potential across various application domains.

关键词： Thermally reduced graphene oxide Polypropylene Creep failure and lifetime prediction