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Synthesis and magnetic properties of CdS/α-Fe_2O_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 Science 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 Engineering, Harbin Engineering university, Harbin 150001, china 1. School of Materials Science 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 Engineering Harbin Engineering University Harbin 150001 China

CdS/α-Fe2O3 hierarchical nanostructures, where the CdS nanorods grow irregularly on the side surface of α-Fe2O3 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 (230 K) than that of the single bulk α-Fe2O3 materials (263 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-Fe2O3 hierarchical nanostructures may be used as multi-functional materials for optoelectronic and magnetic devices.

关键词： α-Fe2O3 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 Science 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 Engineering,Harbin Engineering university,Harbin 150001,china School of Materials Science 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 Engineering 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

microstructure and formation mechanism of twins of laths of austenite with high nitrogen

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Science china(Technological Sciences) 2007年第6期50卷 755-764页

作者： WU CuiLan1,2 & LUO ChengPing2 1 center for High Resolution Electron microscopy, College of Materials Science and Engineering, hunan university, changsha 410082, china 2 College of Mechanical Engineering, South china university of Technology, Guangzhou 510641, china 1. center for High Resolution Electron microscopy College of Materials Science and Engineering Hunan University Changsha 410082 China 2. College of Mechanical Engineering South China University of Technology Guangzhou 510641 China

The microstructure of composite diffusion layer of the nitrided and chromized 0.2% carbon steel is investigated using TEM and EDS. It is found that laths of austenite with high nitrogen (γ N) precipitate from α-ferrite matrix in the deeper zone of the diffusion layer. These γ N laths are all twins, with their {111} twinning planes parallel to the lath axis, thus forming a characteristic "back-to-back" morphology. There are two types of γN lath. The first is a genuinely {111} twin, and γ N and α keep the accurate K-S relationship, and each γ N and α form a sharp and smooth γ N/α inter- face of {335}γN//{341}α, namely habit plane {335}fcc. The second is a pseudo-twin, with micro-twins {111} or faults formed within the two twin components. Localized lattice deformation (relaxation) seems to have occurred at the interfaces of the second type of γ N due to the formation of micro-twins or faults within the twin components. These micro-twins or faults make the orientation relationship (OR) between each of the γN and the α-matrix deviate from the accurate K-S OR, and the OR between two γ N twin components deviate from the genuine {111} twin relation- ship. In addition, the γ N/α interface of the second type of γ N is not as sharp or smooth as that of the first one.

关键词： austenite containing nitrogen, twins, steel 20, nitriding, composite chromizing

Quantitative detection of ING1 mRNA under different gene regulation based on molecular beacon

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Chinese Science Bulletin 2006年第17期51卷 2059-2064页

作者： LIU Bin1,2,3,4, WANG Kemin1,2,3,4, XIAO Zhiqiang5,6, WANG Wei1,3,4, TAN Weihong1,2,3,4, SUN Yi5,6, TANG Hongxing1,3,4 & YANG Xiaohai1,3,41. State Key Laboratory of Chemo/Biosensing and Chemometrics, Hu- nan university, changsha 410082, china 2. Life Science and Biotechnology Institute, hunan university, Chang- sha 410082, china 3. Chemistry and Chemical Engineer College, hunan university, changsha 410082, china 4. hunan Engineering research center for Bio-nanotechnology, hunan university, changsha 410082, china 5. Medical Experiment research center, Xiangya Hospital, Central South university, changsha 410008, china 6. Key Laboratory of Cancer Proteomics of Chinese Ministry of Health, changsha 410008, china State Key Laboratory of Chemo/Biosensing and Chemometrics Hunan University Changsha China Life Science and Biotechnology Institute Hunan University Changsha China Chemistry and Chemical Engineer College Hunan University Changsha China hunan Engineering research center for Bio-nanotechnology Hunan University Changsha China Medical Experiment research center Xiangya Hospital Central South University Changsha China Key Laboratory of Cancer Proteomics of Chinese Ministry of Health Changsha China

The effects of drug treatment, gene transfection, and p53 RNA interference (RNAi) on level of ING1 mRNA in tumor cells were quantitatively detected with the help of ING1 molecular beacon (MB)/cRNA standard curve based on MB detection technology. Results showed that the level of ING1 mRNA could be upregulated by 5-FU treatment or ING1 transfection in low expression cell line of MCF-7 and be inhibited by silencing p53 with RNAi technology in normal expression cell line of CNE2. The level of ING1 varied from 7.7×10?16 to 53.4× 10?16 mol/μg total RNA of tumor cells. The results not only provided evidence for the regulation effects of gene expression but also were applied to investigat- ing the interaction of multigenes on signal transduc- tion pathway.

关键词： ING1 RT-PCR 定量分析分子信号 mRNA

Aspects of recent developments in analytical chemometrics

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Science china Chemistry 2006年第3期49卷 193-203页

作者： LIANG Yizeng1,2, WU Hailong1, SHEN Guoli1, JIANG Jianhui1, LIANG Sheng2 & YU Ruqin1 1. State Key Laboratory of Chemo/Biosensing and Chemometrics, College of Chemistry and Chemical Engineering, hunan university, changsha 410082, china 2. research center of Modernization of Traditional Chinese Medicines, Central South university, changsha 410081, china 1. State Key Laboratory of Chemo/Biosensing and Chemometrics College of Chemistry and Chemical Engineering Hunan University Changsha 410082 China 2. research center of Modernization of Traditional Chinese Medicines Central South University Changsha 410081 China

Some aspects of recent developments in analytical chemometrics are discussed, in par- ticular the developments viewed from the angle of the research efforts undertaken in authors’ labora- tories. The topics concerned include resolution of high-order chemical data, morphological theory and methodology for chemical signal processing, multivariate calibration and chemical pattern recognition for solving complex chemical problems, and resolution of two-way chemical data from hyphenated chromatographic instruments.

关键词： chemometrics, high-order chemical data, pattern recognition, multivariate calibration and resolution.

TEM STUDY OF C-B_4C-SiC COMPOSITES WITH SILICON ADDITIVE

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Acta Metallurgica Sinica(English Letters) 1995年第2期8卷 92-96页

作者： ZHAO Lihua WU Lijun HUANG Qizhong YANG Qiaoqin 1)(Material research and Test center,hunan university,changsha,china)2)(Powder Metallurgy research Institute,center-South university of Technology,changsha,china)3)(Laboratory of Atomic Imaging of Solids, Ins hunan Univ Changsha China

C-B4C-SiC composites with silicon additive obtained by the hot press sintering method are studied by means of transmission electron microscopy(TEM).When the specimens are heated to 1800℃,their structure does not *** the specimens are heated to 2000℃,carbon begins to graphitize. Moreover,two monoclinic phases are *** monoclinic phase named as the M phase belongs to C-center monoclinic lattice with a=0.90nm,b=0.59nm,c=0.54nm and β=119.3°.The other monoclinic phase named as the Ml phase also belongs to C-center monoclinic lattice but with a=0.85nm,b=0.49nm,c=0.53nm and β=123.6°.

关键词： C-B_4C-SiC composite electron microscopy

Prediction of the amount of urban waste solids by applying a gray theoretical model

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Journal of Environmental Sciences 2003年第1期15卷 43-46页

作者： LI Xiao ming, ZENG Guang ming, WANG Ming, LIU Jin jin (Department of Environmental Science and Technology, hunan university, changsha 410082, china. Department of Environmental Science and Technology Hunan University Changsha 410082 China

Urban waste solids are now becoming one of the most crucial environmental problems. There are several different kinds of technologies normally used for waste solids disposal, among which landfill is more favorable in china than others, especially for urban waste solids. Most of the design works up to now are based on a roughly estimation of the amount of urban waste solids without any theoretical support, which lead to a series problems. To meet the basic information requirements for the design work, the amount of the urban waste solids was predicted in this research by applying the gray theoretical model GM (1,1) through non linear differential equation simulation. The model parameters were estimated with the least square method (LSM) by running a certain MATALAB program, and the hypothesis test results show that the residual between the prediction value and the actual value approximately comply with the normal distribution N (0,0 21 2), and the probability of the residual within the range (-0 17, 0 19) is more than 95%, which indicate obviously that the model can be well used for the prediction of the amount of waste solids and those had been already testified by the latest two years data about the urban waste solids from Loudi City of china. With this model, the predicted amount of the waste solids produced in Loudi City in the next 30 years is 8049000 ton in total.

关键词： gray theoretical model prediction waste solids

microSTRUCTURE　OF　Ti－B－NFILM　AND　INTERFACEFORMED　BY　N　ION　BOMBARDMENTON　A　Ti－B　FILM

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Acta Metallurgica Sinica(English Letters) 1996年第3期9卷 211-216页

作者： YANG Qiaoqin ZHAO Lihua WU Lijun LI Xueqian and DU Haiqing(Materials Test and research center, hunan university, changsha 410082, china)WEN Lishi(Institute of Metal research, Chinese Academy of Sciences, Shenyang 110015, china)

Ti-B-N film was deposited on W18Cr4 V high speed steels by using N ion bombardment on an EB-ion plating Ti-B film. It was found that Ti, B and N in the film are homogeneous, but there exists an extended diffusion zone at the film / substrate interface on the basis of the results of IPMA, EPMA and TEM. The boron content of the film is 9.5 at.%, as given by nuclear reaction analysis. The ratio of nitrogen to titanium of the film is about 0.94, as given by EPMA. The width of a high N concentration region in the Ti-B-N film fowned by N ion bombardment of a Ti-B film is about 100 nm; N and Ti penetrates into the substrate, resulting in a wide interfacial diffusion zone. The width of the diffusion zone obtained with TEM and EDAX is about 20 nm. μ-diffraction patterns of the interface show that FeTi, Fe_2 Ti, and Ti_2N existin the interfacial diffusion zone. TEM observation of film and interface show a dense and fine nano-crystalline structure of the film and a dense close interfactal bonding of the film to substrate. Electron diffraction patterns and the values of electrun binding energy by XPS show that the film consists mainly of fcc TiN, with dispersed simple orthorhombic TiB, cubic BN and simple hexagonal Ti-B-N phases. The results show that the N ion hombardment extends the film / substrate interfacial diffusion zone and stimulates chemical reaction both in the film and interface.

关键词： microstructure Ti-B-N film N ion bombardment interface

DISSOLUTION THEORY OF GOLD IN ALKALINE THIOUREA SOLUTION(Ⅱ)——Electrochemical Study on Au-Fe Mix Anode in Alkaline Thiourea Solution Containing Na_2SO_3

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中国有色金属学会会刊：英文版 1999年第2期9卷 189-194页

作者： Chai Liyuan1 and Masazumi Okido2 1 Department of Nonferrous Metallurgy,Central South university of Technology, changsha 410083, P. R. china2 center for Integrated research in Science and Engineering,Nagoya university, Nagoya 464, Japan 中南工业大学有色冶金系湖南长沙 Nagoya Univerisity 日本

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关键词： alkaline thioureasodium sulfitemix anode of gold and iron