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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. {2. 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.

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,{2. 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 {2. 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, {2. 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 2., nitriding, composite chromizing

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 Science and Engineering, Beijing Institute of Technology, Beijing 100081, china 2.micro-nano technologies research center, {2. 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 {2. 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-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

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 {2. 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 {2. 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

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,{2. 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 2.00℃,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=12..6°.

关键词： C-B_4C-SiC composite electron microscopy

Dissolution theory of gold in alkaline thiourea solution(Ⅲ) ——Thermodynamics on dissolution of gold in alkaline thiourea solution containing Na _2.O_3

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中国有色金属学会会刊：英文版 1999年第3期9卷 646-650页

作者： Chai Liyuan(柴立元) 1, Masazumi Okido 2.1. Department of Nonferrous Metallurgy, Central South University of Technology, changsha 410083, P.R.china 2. {2. for Integrated research of Science and Engineering, Nagoya University,Nagoya 464, Japan 中南工业大学有色冶金系湖南长沙 Nagoya University 日本

The oxidants of gold were investigated in an alkaline thiourea solution containing Na 2.O 3, in which Na 2. 2. 8 is a proper oxidant for dissolving gold because of in such homogeneous sulfur system coexisting complex agent, oxidant and stabilizing agent. The thermodynamic analyses were conducted on the dissolving of gold in the alkaline thiourea solution containing Na 2.O 3 by the oxidants oxygen or Na 2. 2. 8. The results show that the possibility of gold dissolution reduces with increasing pH value, while oxygen acts as oxidant; and when Na 2. 2. 8 acts as the oxidant of gold in the alkaline thiourea solution of pH 12.5, decomposition potential of thiourea decreases from the standard value 0.42.V to -0.32.V, also the dissolution trend of gold enhances with shifting the mix potential of the solution to the positive direction.

关键词： thermodynamic analysis gold dissolution thiourea leaching Document code:A

Systematic Studies of Nitrogen Loss from Paddy Soils Through Leaching in the Dongting Lake Area of china

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Pedosphere 2011年第6期21卷 753-762页

作者： JI Xiong-Hui ZHENG Sheng-Xian SHI Li-Hong LIU Zhao-Bing Soil and Fertilizer Institute of hunan Province Changsha 410125 （China） hunan Agricultural Environment research {2. Changsha 410125 （China）

A two-year lysimeter study was conducted to study the effects of different fertilizers and soils on nitrogen leaching loss in a double rice cropping system by considering three major types of paddy soils from the Dongting Lake area. The results showed that N concentration in the leachate did not differ significantly among the treatments of urea, controlled release N fertilizer and pig manure and that all these fertilizers produced higher total nitrogen （TN） concentrations in the leachate compared to the case where no fertilizer was applied. The TN leaching loss following urea treatment accounted for 2.2.%, 0.66%, and 1.50% of the amount of N applied in the alluvial sandy loamy paddy soil （ASL）, purple calcareous clayey paddy soil （PCC）, and reddish-yellow loamy paddy soil （RYL）, respectively. Higher TN loss was found to be correlated with the increased leachate volume in ASL compared with RYL, and the lowest TN loss was observed in the PCC, in which the lowest leachate volume and TN concentration were observed. Organic N and NH＋-N were the major forms of N depleted through leachate, accounting for 56.8% and 39.7% of TN losses, respectively. Accordingly, soil-specific fertilization regimens are recommended; in particular, the maximum amount of fertilizer should be optimized for sandy soils with a high infiltration rate. To avoid a high N leaching loss from rice fields, organic N fertilizers such as urea or coated urea should primarily be used for surface topdressing or shallow-layer application and not for deep-layer application.

关键词： double rice cropping fertilizer application leachate nitrogen concentration

Design of a Digital Management System for the Sintering Material Ground

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International Journal of Automation and computing 2012年第6期9卷 587-593页

作者： Yan Cai 1,2.Min Wu 1,2.Jin-Ni Zhou 1,2.Xin Chen 1,2.1 School of Information Science and Engineering,Central South University,changsha 410083,china 2.{2. Engineering Laboratory for Advanced Control and Intelligent Automation,changsha 410083,china 1. School of Information Science and Engineering Central South University Changsha 410083 China 2. hunan Engineering Laboratory for Advanced Control and Intelligent Automation Changsha 410083 China

There are many kinds and a large number of raw materials in the sintering material ground to be managed,while it is difficult to obtain the precise inventory values,which often leads to high ***,the external factors of material ground are difficult to handle,such as weather variation,order fluctuation,measurement failure and so *** solve such raw material management problems,a digital management system has been ***,the practical requirements and the raw material management processes are ***,optimization and prediction methods are used to calculate the inventory according to the practical *** the help of practical technologies and production conditions,the developed system has been applied to a large-scale sintering material *** practical running results of the application demonstrate the validity of the proposed digital management system.

关键词： Digital sintering material ground prediction methods optimization methods management system.