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Preparation of Sn-doped In_2._3 nanopowders by a solvothermal process

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Rare Metals 2008年第1期27卷 27-31页

作者： GU Yingying QIN Liping school of Chemistry and Chemical engineering Central South University Changsha 410083 China science and Technology Department Guangxi University ofTectmology Liuzhou 545006 China

Sn-doped In2.3（ITO） nanopowders in square shape were prepared in ethylene solvent by a solvothermal process,using In（4N） and SnCl4·5H2. as starting *** effects of solvothermal temperature and coprecipitation pH on the products were investigated using XRD,XPS,and *** of InOOH crystals and In4Sn3O12.crystals were prepared at 2.0°C or 2.0°C and ITO nanopowders with cubic structure were obtained at 2.0°C or above 2.0°*** the coprecipitation pH was 6,the product was ITO with impurity *** the pH was 9,the product was single phase ITO.

关键词： composite material ITO solvothermal process square shape

Influence of Mg5Ga2.compound on microstructures and electrochemical properties of Mg-5%Hg-2.%Ga alloy

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Progress in Natural science:materials International 2011年第1期21卷 73-79页

作者： Yan FENG~1,Ri-chu WANG~1,Chao-qun PENG~1,Hui-ping TANG~2.Hai-yan LIU~2.1.school of materials {2. and engineering,central south university,changsha 41.083,china 2.Northwest Institute for Non-ferrous Metals Research,Xi'an 710016,china [a] school of materials {2. and engineering Central South University Changsha 410083 China [b] Northwest Institute for Non-ferrous Metals Research Xi'an 710016 China

The Mg-5%Hg-2.%Ga（mole fraction） alloy was *** at 573-673 K for different times was carried out to ensure the fine dispersion of the *** electron microscopy（SEM）,X-ray diffractometry（XRD） and energy spectrum analysis（ESA） were employed to characterize the microstructures and phases of the Mg-5%Hg-2.%Ga *** electrochemical and corrosion behaviors of the above alloy were studied by potentiodynamic,galvanostatic and electrochemical impedance spectroscopy（EIS） *** relationship between the Mg5Ga2.ompound and the electrochemical properties of the Mg-5%Hg-2.%Ga alloy was *** results demonstrate that the heat treatment at 573-673 K for 2. h accelerates the growth of the intergranular eutectic Mg-Mg5Ga2.nd the heat treatment for 2.0 h prompts the transition of eutectic to dispersed linear Mg phase and *** transition enhances the electrochemical activity and corrosion resistance of the Mg-5%Hg-2.%Ga *** the galvanostatic tests with current density of 100 mA/cm2.the most negative potential,-1.991 V, occurs in the sample aged for 2.0 *** largest corrosion current density of 44.36 mA/cm2.ccurs in the sample aged for 2. h.

关键词： Mg-Hg-Ga alloys anodic behavior Mg5Ga2.phase intergranular corrosion

Polycomb group proteins and their roles in carcinogenesis

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Chinese science Bulletin 2012年第18期57卷 2259-2264页

作者： XIAO LanBo 1,2.3,TAO YongGuang 1,2.3,LI LiLi 1,2.3,4 & CAO Ya 1,2.31 Key Laboratory of Carcinogenesis of Ministry of Health,Xiangya school of Medicine,central {2. university,changsha 410078,china 2.Key Laboratory of Carcinogenesis and Cancer Invasion of Ministry of Education,Xiangya school of Medicine,central {2. university,changsha 410078,china 3 Cancer Research Institute,Xiangya school of Medicine,central {2. university,changsha 410078,china 4 Cancer Epigenetics Laboratory,State Key Laboratory in Oncology in {2. china,Chinese university of Hong Kong,Hong Kong 999077,china Key Laboratory of Carcinogenesis of Ministry of Health Xiangya School of Medicine Central South University Key Laboratory of Carcinogenesis and Cancer Invasion of Ministry of Education Xiangya School of Medicine Central South University Cancer Resea

In the cell nucleus,DNA is wound around histone proteins,which are then packed together to form *** can be chemically tagged by methyl and acetyl *** group (PcG) proteins attach methyl groups to genes,which block their *** is similar to the attachment of methyl groups to gene promoters by DNA methyltransferases (DNMTs).This action is directly linked with tumor initiation and metastasis via the promotion of anti-senescence and anti-apoptosis pathways,and by facilitating epithelial mesenchymal transition (EMT).Cell fate transcriptional factors (CFTFs) and long non-coding RNAs (long ncRNAs) recruit PcG proteins to the promoters of tumor suppressor genes,resulting in epigenetic gene silencing by influencing chromatin structure and DNA ***,PcG proteins are potential diagnostic markers and targets for new chemoprevention and therapeutic strategies.

关键词：组蛋白 DNA甲基转移酶基因启动子癌变非编码RNA PEG 凋亡途径抑癌基因

Synthesis and magnetic properties of CdS/α-Fe_2._3 hierarchical nanostructures

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science china(Physics,Mechanics & Astronomy) 2009年第7期52卷 997-1002页

作者： CHEN YuJin1,2.3, SHI XiaoLing1, CAO MaoSheng1 & ZHU ChunLing4 1 school of materials {2. and engineering, Beijing Institute of Technology, Beijing 100081, china 2.Micro-Nano Technologies Research Center, Hunan university, changsha 410082. china 3 College of {2., Harbin engineering university, Harbin 150001, china 4 College of material {2. and Chemical engineering, Harbin engineering university, Harbin 150001, china 1. school of materials {2. and engineering Beijing Institute of Technology Beijing 100081 China 2. Micro-Nano Technologies Research Center Hunan University Changsha 410082 China 3. College of science Harbin Engineering University Harbin 150001 China 4. College of material science and Chemical {2. Harbin Engineering University Harbin 150001 China

CdS/α-Fe2.3 hierarchical nanostructures, where the CdS nanorods grow irregularly on the side surface of α-Fe2.3 nanorods, were synthesized via a three-step process. The diameters and lengths of CdS nanorods can be tuned by changing the ethylenediamine (EDA) and Cd ion concentrations. The magnetic investigations by superconducting quantum interference device indicate that the hierarchical nanostructures have an Morin transition at lower temperature (2.0 K) than that of the single bulk α-Fe2.3 materials (2.3 K). Importantly, the hierarchical nanostructures exhibit weakly ferromagnetic characteristics at 300 K. A sharp peak assigned to the surface trap induced emission are observed in room temperature PL spectra. Combining with the optoelectronic properties of CdS, the CdS/ α-Fe2.3 hierarchical nanostructures may be used as multi-functional materials for optoelectronic and magnetic devices.

关键词： α-Fe2.3 CdS hierarchical nanostructures magnetic properties

One-pot synthesis of crystalline SnO_2.nanoparticles and their low-temperature ethanol sensing characteristics

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science china(Physics,Mechanics & Astronomy) 2009年第10期52卷 1601-1605页

作者： CHEN YuJin1,2.3,ZHU ChunLing4,WANG LiJiao3 & WANG TaiHong2.1 school of materials {2. and engineering,Beijing Institute of Technology,Beijing 100081,china 2.Micro-Nano Technologies Research Center,Hunan university,changsha 410082.china 3 College of {2.,Harbin engineering university,Harbin 150001,china 4 College of material {2. and Chemical engineering,Harbin engineering university,Harbin 150001,china school of materials {2. and engineering Beijing Institute of Technology Beijing 100081 China Micro-Nano Technologies Research Center Hunan University Changsha 410082 China College of science Harbin Engineering University Harbin 150001 China College of material science and Chemical {2. Harbin Engineering University Harbin 150001 China

Crystalline SnO2.nanoparticles(NPs) with a diameter less than 6 nm are synthesized using potassium stannate trihydrate as the precursor in a basic *** synthesized NPs can detect ethanol at a ppm level even at 100℃.Furthermore,the NPs have good selectivity to *** excellent ethanol sensing performances are attributed to the small size effect according to the space-charge model.

关键词： SnO2 nanoparticles sensing characteristics

CONTROLLABILITY FOR A PARABOLIC EQUATION WITH A NONLINEAR TERM INVOLVING THE STATE AND THE GRADIENT

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Acta Mathematica Scientia 2010年第5期30卷 1593-1604页

作者：许友军刘振海 school of Mathematics and Physics University of South China school of Mathematical sciences and Computing Technology Central South University

In this article, we consider the controllability of a quasi-linear heat equation involving gradient terms with Dirichlet boundary conditions in a bounded domain of *** results are established by using the variational ... 详细信息

关键词： controllability Kakutani fixed-point theorem nonlinear gradient term

Preliminary study on interaction between plant frictional root and rock-soil mass

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science china(Technological sciences) 2010年第7期53卷 1938-1942页

作者： YAN ZhiXin1’2. SONG Yun3, JIANG Ping1’2.& WANG HouYu4 1 Key Laboratory of Mechanics on Disaster and Environment in Western china (Lanzhou university), Ministry of Education, Lanzhou 730000, china 2.school of Civil engineering and Mechanics, Lanzhou university, Lanzhou 730000, china 3 College of Civil engineering and Mechanics, central south university of Forestry and Technology, changsha 410004, china 4 Air Force engineering Design & Research Bureau, Beijing 100077, china 1. Key Laboratory of Mechanics on Disaster and Environment in Western china (Lanzhou university) Ministry of Education Lanzhou 730000 China2. School of Civil Engineering and Mechanics Lanzhou University Lanzhou 730000 China3. College of Civil Engineering and Mechanics Central South University of Forestry and Technology Changsha 410004 China4. Air Force Engineering Design & Research Bureau Beijing 100077 China

The interaction between lateral root system of woody plant and soil mass is similar to the one between shrub, herbage and soil mass, and has the effect of frictional reinforcement on slope soil. It plays an important role in reinforcing soil strength in shallow slope. Therefore, slope soil mass can be considered as a composite of soil and plant roots and the soil strength and stability of shallow slope soil mass are improved. However, current researches still remain on the level of qualitatively analyzing the relation between root and soil mass. In this paper, some exploratory researches on quantitative analysis of the interaction mechanism between root and soil mass are conducted. With the study of interaction between herbage root system (lateral root system of woody plants) and soil mass, the mechanical model of interaction between frictional root and soil mass is established. The accuracy of the model is verified by field experiments of Pinus Yunnanensis. The mechanical model provides a crucial theoretical guidance to quantitatively analyzing the interaction between plant root and soil mass; it also has certain values in application.

关键词： plant slope protection vegetation for slope protection mechanical model frictional root

Preparation and electrochemical performance of spherical Fe_3O_4 as anode materials for Li-ion batteries

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science china(Technological sciences) 2009年第11期52卷 3219-3223页

作者： WANG FangBin, CHEN Jie, HUANG KeLong & LIU SuQin College of Chemistry & Chemical engineering, central south university,{2., china 1. College of Chemistry & Chemical engineering Central South University Changsha 410083 China

Fe3O4 nano-powder was prepared by the hydrothermal method. The structure and morphology of the product were characterized by X-ray diffraction (XRD) and scanning electronic microscopy (SEM). The as-prepared powder has regularly spherical morphology, and the average size of product is about 2. nm. The possible application use of this material as the active mass of anode for rechargeable Li batteries was examined by cyclic voltammeter (CV), galvanostatic charge/*** experimental results showed that this material exhibited large specific capacity at the first cycle, and the discharge and charge capacity retention of this electrode are 37.04% and 48.76%, respectively. Furthermore, the impedance change of Fe3O4 electrode under different cycle number and potential was examined.

关键词： Fe3O4 lithium battery anode electrochemical performance

A composite material model for investigation of micro-fracture mechanism of brittle rock subjected to uniaxial compression

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Journal of central south university of Technology 2001年第4期8卷 258-262页

作者： CHEN Feng,SUN Zong qi,XU Ji cheng,ZHANG Jing yi (Key Laboratory of Nonferrous Metal materials science & {2., central south university, changsha 41.083, china) 1. Key Laboratory of Nonferrous Metal materials science & {2. Central South University 410083 Changsha China

A two phase model of rock was proposed in order to investigate the mechanism of brittle fracture due to uniaxial compression, in which rock was considered to be a composite material consisting of hard grains and colloids. The stress state in colloid region near grains was calculated using Finite Element Method (FEM). The influence of the tensile stresses on the crack initiation and failure process of brittle rock subjected to uniaxial compression was investigated by numerical experiments. The FE results show that tensile stresses are induced easily in the neighboring area of hard grains with the maximum value near grain boundaries. The distribution of tensile stresses depends on the relative position of hard grains. The cracks initiated just near the boundary area of hard grains, which was governed by tensile stress. These results clearly reveal the micro fracture mechanism of brittle rock loaded by uniaxial compression. It can be concluded that the failure mode of brittle rock under uniaxial compression is still tensile fracture from the point view of microstructure. However, since the wide colloid region is still under compressive stress state, further propagation of boundary cracks through this region obviously needs more external load, thus causing the uniaxial compressive strength of rock much higher than its tensile strength obtained via Brazilian (splitting)

关键词： two-phase model micro-fracture rock uniaxial compression