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Science China(Technological Sciences) 2016年第5期59卷 832-838页

作者： WANG Cun Yu CHANG Ying li xiao dong ZHAO Kun Min dong Han East China Branch Central Iron & Steel Research Institute State Key Laboratory of Structural Analysis for Industrial Equipment School of Automotive Engineering Dalian University of Technology Institute of Industrial and Equipment Technology Hefei University of Technology

A two-step quenching and partitioning （Q＆P） treatment was applied to low-carbon alloy steels. The relation of initial martensite - retained austenite - fresh martensite and its effect on microstructure and mechanical properties were investigated by experiments. The results reveal that the volume fraction of retained austenite can reach the peak value of 17%, and the corre- sponding volume fractions of initial martensite and fresh martensite are 40% and 43%, respectively, when the tested steel is treated by initial quenching at 330℃, partitioning at 500℃ for 60s and final quenching to room temperature. Moreover, the micromorphologies of austenite and martensite become finer with the increasing of initial martensite fraction. The elongation is the highest when the volume fractions of initial martensite and retained austenite are 70% and 11%, respectively, meanwhile, the yield strength increases and tensile strength decreases gradually with the increase of initial martensite fraction, which proves that the mechanical properties including elongation, yield strength and tensile strength are based on the comprehensive effect of the retained austenite fraction, the finer microstructure and austenite stability.

关键词： quenching and partitioning microstructure martensite retained austenite mechanical properties

Holographic Gas as Dark Energy

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Communications in Theoretical Physics 2009年第1期51卷 181-186页

作者： li Miao li xiao-dong liN Chun-Shan WANG Yi Interdisciplinary Center for Theoretical Study University of Science and Technology of China Hefei 230026 China Institute of Theoretical Physics Chinese Academy of Sciences Beijing 100080 China

We investigate the statistical nature of holographic gas, which may represent the quasi-particle excitations of a strongly correlated gravitational system. We find that the holographic entropy can be obtained by modifying degeneracy. We calculate thermodynamical quantities and investigate stability of the holographic gas. When applying to cosmology, we find that the holographic gas behaves as holographic dark energy, and the parameter c in holographic dark energy can be calculated from our model. Our model of holographic gas generally predicts c 〈 1, implying that the fate of our universe is phantom-like.

关键词： holographic principle dark energy

Deformation behavior and microstructure of an Al-Zn-Mg-Cu-Zr alloy during hot deformation

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International Journal of Minerals,Metallurgy and Materials 2010年第1期17卷 46-52页

作者： liang-ming Yan Jian Shen Jun-peng li Zhou-bing li xiao-dong Yan General Research Institute for Nonferrous Metals Beijing 100088 China

The hot deformation behavior and microstructures of Al-7055 commercial alloy were investigated by axisymmetric hot compres- sion at temperatures ranging from 300℃ to 450℃ and strain rates from 10^-2 to 10 s^-1, respectively. Microstructures of deformed 7055 alloy were investigated by transmission electron microscopy （TEM）. The dependence of peak stress on deformation temperature and strain rate can be expressed by the hyperbolic-sine type equation. The hot deformation activation energy of the alloy is 146 kJ/mol. Moreover, the flow stress curves predicted by the modified constitutive equations are reasonably consistent with the experimental results, which confirms that the proposed deformation constitutive equations can provide evidence for the selection of hot forming parameters. TEM results indicate that dy- namic recovery is the main softening mechanism during hot deformation.

关键词： aluminum alloys dynamic recovery hot compression deformation behavior constitutive equation

Vapor-liquid equilibria of CH_4, CO_2 and their binary system CH_4 + CO_2: A comparison between the molecular simulation and equation of state

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Science China(Technological Sciences) 2015年第4期58卷 650-658页

作者： YANG Zhi GONG Mao Qiong ZHOU Yuan dong Xue Qiang li xiao dong li Hui Ya WU Jian Feng Key Laboratory of Cryogenics Technical Institute of Physics and Chemistry Chinese Academy of Sciences University of Chinese Academy of Sciences School of Energy and Power Engineering Beihang University

An accurate knowledge about phase behaviors of CH4, CO2 and their binary mixture is crucial in fields of natural gas liquefaction and refrigeration applications. In this work, two all-atom force fields of TraPPE-EH and EMP2 were used for the components CH4 and CO〉 respectively. Then the vapor-liquid equilibria （VLE） of CH4, CO2 and their binary system were calculated via the NVT- and NpT Gibbs Ensemble Monte Carlo Simulations. Meanwhile the traditional method using Equation of State （EoS） to correlate the VLE properties was also investigated. The EoSs considered in this work were three classic cubic RK, SRK, PR and another advanced molecular-based PC-SAFT equations. For pure components, both molecular simulations and the PC-SAFT EoS could obtain satisfactory predictions for all the saturated properties. However, the saturated liquid densities calculated by the cubic EoSs were not so good. It was also observed that the TraPPE-EH force field had a good representation for CH4 molecule, while the EMP2 force field was not enough accurate to represent CO2 molecules. For the mixture CH4 ＋ CO2, SRK and PR showed the best predictions for the saturated pressure-component property, while good results were also obtained via molecular simulations and PC-SAFT EoS. It was suggested that special combining rules or binary interaction parameters were important to obtain enough accurate prediction of the mixed phase behavior. Compared with the cubic EoS, the PC-SAFT and molecular simulation method showed better adaptabilities for both the pure and mixture systems. Besides, the accurate molecular parameters used in the PC-SAFT and molecular simulations could bring about direct and deep understanding about the molecular characteristics.

关键词： molecular simulation equation of state CH4 CO2 vapor-liquid equilibrium

Ionic liquids as efficient phase-transfer catalysts for the solid base-promoted monoalkylation of diethyl malonate

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Chinese Chemical Letters 2007年第3期18卷 279-282页

作者： Hui Sun Juan li xiao Chen Cai dong Jiang li Yi Dai Department of Chemistry East China Normal University Shanghai 200062 China

Ionic liquids （ILs） based on 1,3-dialkylimidazolium and tetraalkylammonium cations were employed as a series of efficient, environmentally benign phase-transfer catalysts （PTCs） for the base-promoted monoalkylation of diethyl malonate. The influence of various heterogeneous bases on yields was studied. Good yields and high selectivity were obtained. Solvent-free, mild reaction condition, short reaction time, and easy purification were the merits of this method. The catalytic system （IL-hase） could also be recycled after the extraction of products with ether.

关键词： Ionic liquids Phase-transfer catalysis Diethyl malonate Alkylation

Laboratory-scale study of the suppression of PCDD/F emission during coal and MSW co-incineration

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Journal of Environmental Sciences 2007年第6期19卷 762-767页

作者： LU Sheng-yong YAN Jian-hua li xiao-dong NI Ming-jiang CEN Ke-fa State Key Laboratory of Clean Energy Utilization Institute for Thermal Power Engineering Zhejiang University Hangzhou 310027 China

The experimental test of co-incinerating Chinese raw municipal solid waste （MSW） and coal in a laboratory-scale tubular reactor was first reported in present study, and the emission of normal gas components and the effects of the S/Cl molar ratio or coal mixing percentages on polychlorinated dibenzo-p-dioxins and dibenzofurans （PCDDs/Fs） emission were investigated and discussed. The results indicated that OCDD was the only PCDD homologues since others like TCDD-HpCDD was hardly detected, while as the categories of PCDF homologues were comparatively much more general. The amount of PCDD was much larger than that of PCDF in all operating conditions. Since ZPCDF/∑PCDD〈〈1, the dominant role of the precursor formation was proven in our experimental conductions. With increasing the coal addition to MSW （from 0 to 16%）, PCDD and PCDF were reduced considerably. Coal and MSW may suppress the PCDD/F emissions efficiently （over 95%） during the MSW incineration process. The PCDD/F suppression results of the present study could be helpful guidance to the industrial application of Chinese MSW and auxiliary coal co-incineration processes. The PCDD/F stack emission data of two industrial incinerators using co-incineration technology in China seem to have a great positive reduction of PCDDs/Fs.

关键词： co-incineration PCDDs/Fs suppression S/Cl molar ratio

Influence of Block Copolymer on Formation and Acid Resistant Properties of Hybrid CaCO_3 Particles

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Chemical Research in Chinese Universities 2009年第1期25卷 112-115页

作者： li xiao-dong HU Qiao-ling ZHAO Shi-fang SHEN Jia-cong Affiliated Stomatology Hospital Zhejiang University College of Medicine Hangzhou 310058 P. R. China Institute of Polymer Composite Zhejiang University Hangzhou 310027 P. R. China

Block copolymer polystyrene-b-poly（acrylic acid）（PS-b-PAA） was used as structural template for the synthesis of CaCO3 microparticles. Through this procedure, acid resistant hybrid CaCO3 micro- spheres were obtained. Acid resistant properties of this type of hybrid CaCO3 were studied. Size measurement shows that the acid resistant properties of the hybrid particles are different in different solutions, such as HCl, EDTA, and H2SO4 solutions.

关键词： Amphiphilic block copolymer Hybrid particle Size control Acid resistance

Structural and electrical transport properties of Cu-doped Fe1-xCuxSe single crystals

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Chinese Physics B 2020年第12期29卷 103-106页

作者： He li Ming-Wei Ma Shao-Bo liu Fang Zhou xiao-li dong International Laboratory for Quantum Functional Materials of Henan and School of Physics and MicroelectronicsZhengzhou UniversityZhengzhou 450001China Beijing National Laboratory for Condensed Matter Physics Institute of PhysicsChinese Academy of SciencesBeijing 100190China Songshan Lake Materials Laboratory Dongguan 523808China University of Chinese Academy of Sciences Beijing 100049China

We report the structural and electrical transport properties of Fe1-xCuxSe(x=0,0.02,0.05,0.10)single crystals grown by a chemical vapor transport *** Cu for Fe suppresses both the nematicity and superconductivity of FeSe single crystal,and provokes a metal–insulator *** Hall measurements show that the Cu substitution also changes an electron dominance at low temperature of un-doped Fe Se to a hole dominance of Cu-doped Fe1-xCuxSe at x=0.02 and 0.1,and reduces the sign-change temperature(TR)of the Hall coefficient(RH).

关键词： iron-based superconductivity crystal growth element substitution Hall coefficient

Removal of PCDDs/Fs from municipal solid waste incineration by entrained-flow adsorption technology

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2006年第11期7卷 1896-1903页

作者： YAN Jian-hua PENG Zheng LU Sheng-yong li xiao-dong CEN Ke-fa State Key Laboratory of Clean Energy Utilization Zhejiang University Hangzhou 310027 China

Entrained flow adsorption using activated carbon as the adsorbent is widely adopted for PCDDs/Fs-abatement in municipal solid waste incineration (MSWI) process. The effects of operating parameters including flue gas temperature, feeding rate of activated carbon, polychlorinated dibenzodioxins and polychlorinated dibenzofurans (PCDDs/Fs) concentration at the inlet of the air pollution control device (APCD), filter materials, pressure drop on PCDDs/Fs removal efficiency are reviewed and commented upon in this paper. Evaluation on the various mechanistic models for entrained flow adsorption is carried out based on the computational simulation in terms of the actual operating condition and theoretical analysis. Finally, an advancement of en- trained flow adsorption in combination of dual bag filter is introduced.

关键词： PCDDs/Fs Entrained flow adsorption Operating parameters Mechanistic model Dual bag filters

Density Functional Theory and Grand Canonical Monte Carlo Simulations of the Hydrogen Storage Properties of Partially Truncated and Open Cage C60 Fullerenes

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Chinese Physics Letters 2011年第11期28卷 99-102页

作者： li xiao-dong TANG Yong-Jian CHENG Xin-Lu ZHANG Hong College of Physical Science and Technology Sichuan UniversityChengdu 610065 Research Center of Laser Fusion China Academy of Engineering PhysicsMianyang 621900 Institution of Atomic and Molecular Physics Sichuan UniversityChengdu 610065

The potential energies of H2 molecules with partially truncated and open cage C_(60) fullerenes,including C_(58),C_(55),C_(54)(I),C54(II)and C_(46),are investigated by means of the density functional theory *** energy barrier for one H2 molecule(with two postures)entering into the nanocage decreases from 435.59(513.45)kcal/mol to 3.64(¡2.06)kcal/mol with the increase of the truncated *** grand canonical Monte Carlo simulations reveal that each nanocage can accommodate only one H_(2) molecule inside its cavity at both 77K and 298 *** the other H2 molecules are adsorbed round the truncated pores outside the ***,the truncated C_(46) can store 2.28wt%H2 molecules at 77 ***,the truncating part of the C60 molecule may be a novel idea to explore C_(60) fullerene as a hydrogen storage material.

关键词： material truncated adsorbed