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Synthesis and characterization of spinel Li_(1.05)Cr_(0.1)Mn_(1.9)O_(4-z)F_z as cathode materials for lithium-ion batteries

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International Journal of Minerals,Metallurgy and Materials 2010年第2期17卷 220-224页

作者： Yan-bin Chen Yang Hu Fang Lian qing-guo liu School of Materials Science and Engineering University of Science and Technology Beijing Beijing 100083 China Beijng Easpring Material Technology Co. Ltd. Beijing 100044 China Beijing General Research Institute of Mining ＆ Metallurgy Beijing 100044 China

Samples with the nominal stoichiometry Li1.05Cr0.1Mn1.9O4-zFz（z=0,0.05,0.1,0.15,and 0.2） were synthesized via the solid-state reaction method and characterized by X-ray powder diffraction（XRD）,scanning electron microscopy（SEM）,galvanostatic charge/discharge, and slow rate cyclic voltammetry（SSCV） *** results show that the pure spinel phase indexed to Fd3m can be obtained when z=0, 0.05,and *** substitution of F for O with z≤0.1 contributes to the increase of initial capacity compared with Li1.05Cr0.1Mn1.9O4 spinels. However,when the F-dopant content is designed to be 0.15 and 0.2,the Li1.05Cr0.1Mn1.9O4-zFZ samples deliver relatively low capacity and poor cycling properties at 55℃.

关键词： lithium-ion batteries cathode materials doping electrochemical properties

Abundance analysis of Barium stars

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Chinese Journal of Astronomy and Astrophysics 2009年第4期9卷 431-448页

作者： guo-qing liu Yan-Chun Liang Li-Cai Deng National Astronomical Observatories Chinese Academy of Sciences Beijing 100012 China Graduate University of Chinese Academy of Sciences Beijing 100049 China

We obtain the chemical abundances of six barium stars and two CH subgiant stars based on the high signal-to-noise ratio and high resolution EcheUe spectra. The neu-Iron capture process elements Y, Zr, Ba, La and Eu show obvious overabundances relative to the Sun, for example, their [Ba/Fe] values are from 0.45 to 1.27. Other elements, including Na, Mg, A1, Si, Ca, Sc, Ti, V, Cr, Mn and Ni, show comparable abundances to the Solar ones, and their [Fe/H] covers a range from -0.40 to 0.21, which means they belong to the Galactic disk. The predictions of the theoretical model of wind accretion for binary systems can explain the observed abundance patterns of the neutron capture process elements in these stars, which means that their overabundant heavy-elements could be caused by accreting the ejecta of AGB stars, the progenitors of present-day white dwarf companions in binary systems.

关键词： stars abundances-stars atmospheres-stars chemically peculiar-stars evolution-binaries spectroscopic

Thermal Behavior and Kinetics of Raw/Pyrolytic Wood and Coal Blends during Co-combustion Process

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Journal of Iron and Steel Research(International) 2016年第9期23卷 917-923页

作者： Jian DING qing-cai liu Li-jun JIANG guo-qing liu Shan REN Jian YANG Lu YAO Fei MENG College of Materials Science and Engineering Chongqing University

The thermal properties of raw wood（RW） biomass,corresponding pyrolytic wood（PW）biomass,and their blends with anthracite coal（AC） were evaluated under combustion conditions with a thermogravimetric analysis（TGA）*** blending ratios of the biomass with AC ranging from 0 to 100 mass% were taken into consideration to investigate the thermal behavior and kinetics of these blends during their *** blends with different ratios of the RW to AC and 100% AC（100AC）,two distinct mass loss peaks related to the release or combustion process of the volatiles and the combustion of the char were *** addition of a higher ratio of RW or PW into AC can improve the combustion process of the *** thermal behavior of the RW/AC or PW/AC blends could not be characterized by a simple linear correlation of their pure material thermal *** the RW/PW addition ratios varying from 25 mass% to 80 mass%,the apparent activation energy of the blends gradually decreased from 48.46 to 34.93 kJ/mol and from 82.74 to 37.81 kJ/mol for the RW/AC and PW/AC blends,respectively,with high correlation coefficient（R2） values ranging from 0.995 6 to 0.998 4.

关键词： thermal property thermogravimetric analysis raw wood biomass pyrolytic wood biomass apparent activation energy

Thickening progression mechanism of silica fume-oil well cement composite system at high temperatures

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Petroleum Science 2024年第4期21卷 2793-2805页

作者： Hang Zhang Miao-Miao Hu Peng-Peng Li guo-qing liu qing-Lu Chang Jie Cao Ming liu Wen-Hua Xu Xiu-Jian Xia Jin-Tang guo School of Chemical Engineering and Technology Tianjin UniversityTianjin300350China Zhejiang Institute of Tianjin University Shaoxing312300ZhejiangChina Haihe Laboratory of Sustainable Chemical Transformations Tianjin300192China CNPC Engineering Technology R&D Company Limited Beijing102206China

This work studied the thickening progression mechanism of the silica fume-oil well cement composite system at high temperatures(110-180.C)in order to provide a theoretical guidance for the rational application of silica fume in the cementing *** showed that silica fume seldom affected the thickening progression of oil well cement slurry at 110-120.C,but when temperature reached above130.C,it would aggravate the bulging degree of thickening curves and significantly extend the thickening time,meanwhile causing the abnormal“temperature-based thickening time reversal”and“dosage-based thickening time reversal”phenomena in the range of 130-160.C and 170-180.C *** 130-160.C,the thickening time of oil well cement slurry was mainly associated with the generation rate of calcium hydroxide(CH)*** introduced silica fume would be attracted to the cement minerals'surface that were hydrating to produce CH and agglomerate together to form an“adsorptive barrier”to hinder further hydration of the inner cement ***“adsorptive barrier”effect strengthened with the rising temperature which extended the thickening time and caused the occurrence of the“temperature-based thickening time reversal”*** 170-180.C,the pozzolanic activity of silica fume significantly enhanced and considerable amount of C-S-H was generated,thus the“temperature-based thickening time reversal”vanished and the“dosage-based thickening time reversal”was presented.

关键词： Silica fume Oil well cement Thickening time reversal Pozzolanic reaction Adsorptive barrier CH and C-S-H

The genus Glaucopterum Wagner(Hemiptera: Miridae: Phylinae) from China, with description of two new species

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Zoological Systematics 2014年第3期39卷 388-394页

作者： Xiao-Ming Li guo-qing liu School of Life Sciences Huaibei Normal University Institute of Entomology Nankai University

Three species of mirid genus Glaucopterum from China are presented of which Glaucopterum nitrarium sp. nov. and G. shanxiense sp. nov. are described as new. A key toChinese species is offered. Photographs of the dorsal habitus and illustrations of the genitalia are provided. All type specimens are deposited in Institute of Entomology, Nankai University, Tianjin, China.

关键词： Hemiptera Miridae Phylinae Glaucopterum new species China.

PREPARATION AND CHARACTERIZATION OF SPHERICAL PP/PB ALLOYS WITH MgCl_2-SUPPORTED ZIEGLER-NATTA CATALYST

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Chinese Journal of Polymer Science 2012年第5期30卷 632-641页

作者：贺爱华 Yang-wei Shi guo-qing liu Wei Yao Bao-chen Huang Key Laboratory of Rubber-Plastics Ministry of Education/Shandong Provincial Key Laboratory of Rubber-PlasticsSchool of Polymer Science and EngineeringQingdao University of Science and Technology

Polypropylene （PP）/polybutene-1 （PB） alloys within reactor were prepared by MgCl2-supported Ziegler-Natta catalyst with sequential two-stage polymerization technology. First, propylene homo-polymerizations were carried out to form isotactic polypropylene （iPP） particles containing active catalyst. Then, butene-1 was subsequently polymerized to form polybutene-1 phase inside the iPP particles. Finally, iPP/PB alloys with spherical shape and adjustable PB content were synthesized. The catalytic activity and catalytic stereospecificity of the Z-N catalyst in the two-stage polymerization process are discussed. The composition and physical properties of the PP alloys were characterized by FT-IR, 13C-NMR, SEM, DSC and XRD. It was found that the in-reactor PP alloys are mainly composed of PP and PB with a little amount of poly（butene- co-propylene） random copolymers and poly（butene-block-propylene） block copolymers. SEM measurements verified that the PB phases with size in the range of 300-400 nm dispersed in the PP matrix uniformly. The incorporation of PB upon the PP matrix affects the properties of final products greatly.

关键词： Polymer blends and alloys Polymer synthesis Polypropylene In situ polymerization.

Modulation of P-glycoprotein function by amlodipine derivatives in brain microvessel endothelial cells of rats

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Acta Pharmacologica Sinica 2005年第2期26卷 166-170页

作者： Bian-sheng JI Ling HE guo-qing liu Department of Pharmacology,China Pharmaceutical University,Nanjing 210009,China Department of Pharmacology China Pharmaceutical University Nanjing China

Aim:To investigate whether the amlodipine derivatives,CJX1 and CJX2,havea modulative effect on P-glycoprotein(P-gp)function in rat brain microvesselendothelial cells(RBMEC).Methods:Isolated RBMEC were cultured in DMEM/F 12(1:1)*** amount of intracellular rhodamine(Rh123)was determined,using a fluorescence spectrophotometer,to evaluate the function of ***:The accumulation of Rh123 in RBMEC was potentiated in a concentration-dependent manner after incubation with CJX1 and CJX2 at 1,2.5,5,and 10μmol/L(P0.05).Accumulation of intracellular Rh123 was increased and efflux of intra-cellular Rh123 was decreased in a time-dependent manner from 0-100 min afterCJX1 and CXJ2 at 10 ∴mol/L *** inhibitory effect of CJX1 and CJX2on P-gp function was reversible and remained even at 120 min after removal ofCJX1 and CJX2 at 2.5μmol/L from the ***:CJX1 and CJX2exhibited a potent effect in the inhibition of P-gp function in vitro.

关键词： amlodipine derivatives CJX1 CJX2 verapamil P-glycoprotein blood brain barrier vascular endothelium

Chemical abundance analysis of 19 barium stars

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Research in Astronomy and Astrophysics 2016年第1期16卷 159-174页

作者： guo-Chao Yang Yan-Chun Liang Monique Spite Yu-Qin Chen Gang Zhao Bo Zhang guo-qing liu Yu-Juan liu Nian liu Li-Cai Deng Francois Spite Vanessa Hill Cai-Xia Zhang College of Physics and Information Engineering Hebei Normal University Shijiazhuang 050024 China Key Laboratory of Optical Astronomy National Astronomical Observatories Chinese Academy of Sciences Beijing 100012 China University of Chinese Academy of Sciences Beijing 100049 China GEPI Observatoire de Paris-Meudon 92195 Meudon France Physics Department and Tsinghua Center for Astrophysics Tsinghua University Beijing 100084 China Astronomy Department Beijing Normal University Beijing 100875 China Department of Physics Shijiazhuang University Shijiazhuang 050035 China

We aim at deriving accurate atmospheric parameters and chemical abundances of 19 barium（Ba） stars, including both strong and mild Ba stars, based on the high signal-to-noise ratio and high resolution Echelle spectra obtained from the 2.16 m telescope at Xinglong station of National Astronomical Observatories, Chinese Academy of Sciences. The chemical abundances of the sample stars were obtained from an LTE, plane-parallel and line-blanketed atmospheric model by inputting the atmospheric parameters（effective temperatures Teff, surface gravities log g, metallicity [Fe/H] and microturbulence velocity ξt） and equivalent widths of stellar absorption lines. These samples of Ba stars are giants as indicated by atmospheric parameters, metallicities and kinematic analysis about UVW velocity. Chemical abundances of 17 elements were obtained for these Ba stars. Their Na, Al, α- and iron-peak elements（O, Na, Mg, Al, Si, Ca,Sc, Ti, V, Cr, Mn, Ni） are similar to the solar abundances. Our samples of Ba stars show obvious overabundances of neutron-capture（n-capture） process elements relative to the Sun. Their median abundances of[Ba/Fe], [La/Fe] and [Eu/Fe] are 0.54, 0.65 and 0.40, respectively. The Y I and Zr I abundances are lower than Ba, La and Eu, but higher than the α- and iron-peak elements for the strong Ba stars and similar to the iron-peak elements for the mild stars. There exists a positive correlation between Ba intensity and [Ba/Fe].For the n-capture elements（Y, Zr, Ba, La）, there is an anti-correlation between their [X/Fe] and [Fe/H]. We identify nine of our sample stars as strong Ba stars with [Ba/Fe]〉0.6 where seven of them have Ba intensity Ba=2-5, one has Ba=1.5 and another one has Ba=1.0. The remaining ten stars are classified as mild Ba stars with 0.17〈[Ba/Fe]〈0.54.

关键词： methods: observational - stars: abundances - stars: atmospheres - stars: chemically peculiar- stars: kinematics and dynamics - stars: late-type

Dermatomyositis associated with gallbladder carcinoma:A case report

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World Journal of Hepatology 2013年第4期5卷 230-233页

作者： qing-Feng Ni guo-qing liu Li-Yong Pu Liang-Liang Kong Lian-Bao Kong Department of Liver Transplantation Center The First Affiliated Hospital of Nanjing Medical UniversityThe National Institute of Living Donor Liver Transplantation

Patients with gallbladder carcinoma can present with a variety of paraneoplastic syndromes,including Cushing's syndrome,hypercalcemia,acanthosis nigricans,bullous pemphigoid,dermatomyositis and the sign of Leser-Tré*** resection of the primary tumor results in resolution of these paraneoplastic *** present a 67-year old female with facial and cervical erythema who was initially diagnosed with ***,an abdominal computed tomography(CT)and positron emission tomographyCT scan was suspicious for gallbladder carcinoma with lymph node *** surgical resection,her dermatomyositis was *** case demonstrates that dermatomyositis may be a manifestation of preexisting gallbladder carcinoma.

关键词： Dermatomyositis Paraneoplastic syndromes Gallbladder carcinoma