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Journal of Pharmaceutical Analysis 2010年第2期22卷 97-101页

作者： Qin Xiao1,2.Hui Chen2.Jin-Ming Lin2.1. college of Ocean,Hebei Agricultural university,Qinhuangdao 066003 2. The Key Laboratory of Bioorganic Phosphorus Chemistry & {2. Biology,Department of Chemistry,Tsinghua university,Beijing 100084,China. college of Ocean Hebei Agricultural University Qinhuangdao 066003 China Key Laboratory of Bioorganic Phosphorus Chemistry and chemical Biology Department of Chemistry Tsinghua University Beijing 100084 China

A simple and rapid expression and purification method of recombinant firefly luciferase was developed for bacteria detection. A modified luciferase gene from North American firefly Photinus pyralis was cloned into pET2.a expression vector and the recombinant protein was produced in Escherichia coli BL2.. The recombinant luciferase,equipped with a polyhistidine affinity tag,was purified by immobilized metal ion affinity chromatography (IMAC). The approach generated an abundant expression and an efficient purification of a recombinant luciferase with final yield 1.995mg/L of cell culture. Experiments on the recombinant luciferase also showed that the relative light units (RUL) of the enzyme were 5.8×108,and the specific activity was 2.9×1010 RLU/mg. By applying adenosine triphosphate (ATP) bioluminescence to detection of the coin bacteria using the recombinant protein,the ATP content of bacteria was 9.48×10-16mol/mL,and was identical to the bacteria counts (4500CFU/mL) in order of magnitude. Taken together,our results provided a simple and efficacious method of the preparation of recombinant luciferase,which could be applied in the determination of bacteria via ATP bioluminescence.

关键词： ATP bioluminescence bacterial detection expression firefly luciferase purification

Correlation between the Standard Formation Enth alpy and the Path Index of Pyridine Derivatives

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Wuhan university Journal of Natural Sciences 2000年第2期5卷 229-232页

作者： LI Liang chao 1 ,LIAO Gui ying 1,2.,JIANG Sheng bin 2.,WANG Ying xi 2.,SUN Ju tang 3 1. Departmnt of Chemistry, Jingzhou normal college, Jingzhou, China, 434100 2. Hubei, Research Institute of Chemistry, Wuhan, China, 430074 Departmnt of Chemistry Jingzhou Normal College Jingzhou China 434100 Departmnt of Chemistry Jingzhou Normal College Jingzhou China 434100 Hubei Research Institute of Chemistry Wuhan China 430074 Hubei Research Institute of Chemistry Wuhan China 430074 college of Chemistry Wuhan University Wuhan China 430072

A formulated as △fH m ? (PPDs,g)=a+ΣbiPi + cifi is put forward for estimating standard formation enthalpies of pyridine-derivatives (PDDs), in which,P i is path index andc i f i is an amended term of interaction between substituent and N atom on pyridine ring. The Calculations based on the model were carried out for some pyridine-derivatives. The values of standard formation enthalpy calculated are consistent with those in literature.

关键词： Key words pyridine derivatives standard formation enthalpy path index

Analysis of Low-polar Ginsenosides in Steamed Panax Ginseng at High-temperature by HPLC-ESI-MS/MS

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chemical Research in Chinese Universities 2012年第1期28卷 31-36页

作者： ZHANG Yu-chi1,2. PI Zi-feng1, LIU Chun-ming2. SONG Feng-rui1, LIU Zhi-qiang1 and LIU Shu-ying1 1. Changchun Center of Mass Spectrometry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 13002., P. R. China 2. Central Laboratory, Changchun normal university, Changchun 130032. P. R. China Changchun Center of Mass Spectrometry Changchun Institute of Applied Chemistry Chinese Academy of Sciences Changchun 130022 Central Laboratory Changchun Normal University Changchun 130032

A high performance liquid chromatography coupled with electrospray ionization-tandem mass spectrome try（HPLC-ESI-MS/MS） method was developed for the analysis and identification of ginsenosides in the extracts of raw Panax ginseng（RPG） and steamed Panax ginseng at high temperatures（SPGHT）. A total of 2. ginsenosides were extracted include of which 10 low-polar ginsenosides, such as ginsenosides F4, Rk3, Rh4, 2.S-Rg3, 2.R-Rg3 and so on, were identified according to their HPLC retention time and MS/MS data. The results indicated that the low polar ginsenosides were seldom found in RPG. For the exploration of the transformation pattern of the ginsenosides in steam processing, the standards of ginsenosides Re, Rg1, Rb1, Rc, Rb2. Rb3 and Rd were selected and hydrolyzed at a temperature of 12. oC. The results show that these polar ginsenosides can be converted to low-polar ginsenosides such as Rg2. Rg6, F4, Rk3 and Rg5 by hydrolyzing the sugar chains.

关键词： Ginsenoside Hydrolysis Steamed Panax ginseng High performance liquid chromatography coupled withelectrospray ionization-tandem mass spectrometry(HPLC-ESI-MS/MS)

On 3-colorability of planar graphs without adjacent short cycles

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Science China Mathematics 2010年第4期53卷 1129-1132页

作者： WANG YingQian 1,MAO XiangHua 1,LU HuaJing 2.& WANG WeiFan 1 1 college of Mathematics,Physics and Information engineering,Zhejiang {2. university,Jinhua 32.004,China 2.college of Basic Science,Ningbo Dahongying university,Ningbo 315175,China college of Mathematics Physics and Information Engineering Zhejiang Normal University college of Basic Science Ningbo Dahongying University

A short cycle means a cycle of length at most *** this paper,we prove that planar graphs without adjacent short cycles are *** improves a result of Borodin et al.(2.05).

关键词： planar graph coloring extension cycle

Effects of water phase concentration on the emulsion polymerization of polyaniline

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Journal of Central South university of Technology 2001年第2期8卷 140-142页

作者： PAN Chun yue 1,CHEN Zhen hua 2.HUANG Yong li 1,HUANG Ke long 1 (1.college of Chemistry and chemical {2., Central South university, Changsha 410083, China 2.Department of Materials Science and {2., Central South university, Cha college of Chemistry and chemical {2. Central South University Changsha China Department of Materials Science and engineering Central South University Changsha China

The emulsion polymerization of aniline in three phase system of xylene functionalized protonic acid water was carried out using (NH 4) 2. 2. 4 as oxidant. The influences of water phase concentration on the viscosity, conductivity, transmittance of polyaniline(PAN) latex and its powders were studied. The results show that the properties of PAN prepared through the emulsion polymerization are influenced by the amount of water used in the polymerization. The morphology of PAN varies with the water phase concentration used in the polymerization, which may result in the change of properties of PAN latex and its powders. When the volume fraction of water (φ) is about 2.% 30%, the prepared PAN powder has higher conductivity, and the PAN latex has appropriate viscosity and particle size. The consumption of xylene was reduced at high φ value.

关键词： polyaniline emulsion polymerization water concentration property

A Single-phase of Supercritical CO_2.Polystyrene Solution in Foam Extrusion

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Journal of Wuhan university of Technology(Materials Science) 2008年第6期23卷 804-808页

作者：吴晓丹 college of Mechanical and Electronic engineering Guangdong Polytechnic Normal University

The high quality single-phase solution of CO2. Polystyrene was achieved,by analyzing the influential factors for polymer microcellular foaming *** curve of pressure distribution along the barrel was *** axial position of gas-injecting port on the barrel was chosen form the results of stable foaming,and the number of gas-injecting ports in the circumference of the barrel was determined from the CO2.solubility in *** effect of the screw rotation speed on CO2.solubility was studied,and the effects of pressure difference between the gas and the polymer melt on gas-injecting process and on the foaming stability were *** influence of the gas temperature before injection on the single-phase of CO2.Polystyrene solution also was studied.

关键词： polymer extrusion foaming solubility single-phase solution

Study on NDVI-T_s space by combining LAI and evapotranspiration

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Science China Earth Sciences 2006年第7期49卷 747-754页

作者： HAN Lijuan1,2.3, WANG Pengxin4, YANG Hua1,2.3, LIU Shaomin1,2.3 & WANG Jindi1,2.3 1. Research Center for Remote Sensing and GIS, School of Geography, Beijing normal university, Beijing 100875, China 2. State Key Laboratory of Remote Sensing Science, Beijing 100875, China 3. Beijing Key Laboratory for Remote Sensing of Environment and Digital Cities, Beijing 100875, China 4. Department of Information Management, {2. of Information and Electronic engineering, China Agricultural university, Beijing 100083, China Research Center for Remote Sensing and GIS School of Geography Beijing Normal University Beijing China State Key Laboratory of Remote Sensing Science Beijing China Beijing Key Laboratory for Remote Sensing of Environment and Digital Cities Beijing China Department of Information Management College of Information and Electronic Engineering China Agricultural University Beijing China

This paper focuses on interpreting the different spatial relationships between NDVI and Ts, a triangular or a trapezoid, and on analyzing transformation conditions, the physical and ecological meanings of the vegetation index-surface temperature space as well. Further, we use the Tempera-ture-Vegetation Dryness Index (TVDI) to explain the existent meaning of a triangular space after NDVI reaches its saturated state by employing the relationships between NDVI, LAI and evapotranspiration. The specific relations between NDVI and Ts are useful for describing, validating and updating land surface models.

关键词： NDVI, land surface temperature, evapotranspiration, leave area index.

Preparation and NO2.Sensing Characteristics of LaFeO3 Nanoparticles

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稀有金属材料与工程 2006年第S3期 165-166页

作者： Xiangdong Lou~1 Xiaohua Jia~1 Jiaqiang Xu~2.(1.college of Chemistry and Environmental Science,Henan normal {2.,Xinxiang 453007,China) (2.college of Materials and chemical engineering,Zhengzhou {2. of Light Industry,Zhengzhou 450002.China)

LaFeO3nanoparticles were prepared by decomposing a precursor La[Fe（CN）6]·4H2. at 800℃,the precursor was synthesized by a coordination precipitation process at room *** decomposing mechanism of the precursor was investigated by analyzing TG-DSC *** crystal structure,particle size and ceramic microstructure were characterized by X-ray diffraction （XRD） and transmission electron microscopy （TEM）.Furthermore,the gas sensing properties were tested at static *** can be shown that LaFeO3nanoparticles are highly crystallized after sintering at 800℃,the particle size is about 50 *** sensor based on LaFeO3nanoparticles shows remarkable sensitivity to NO2.

关键词： thermal decomposition gas sensor LaFeO3

Applying flexible molecular docking to simulate protein retention behavior in hydrophobic interaction chromatography

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Science China Chemistry 2007年第5期50卷 675-682页

作者： ZHOU Peng1, TIAN FeiFei1 & LI ZhiLiang1,2.1 college of Chemistry and chemical {2., Chongqing university, Chongqing 400044, China 2.State Key Laboratory of Chemo/Biosensing and Chemometrics, Changsha 410082. China college of Chemistry and chemical {2. Chongqing University Chongqing China State Key Laboratory of Chemo/Biosensing and Chemometrics Changsha China

Interaction between proteins and stationary phase in hydrophobic interaction chromatography (HIC) is differentiated into two thermodynamic processes involving direct nonbonding/conformation interac- tion and surface hydrophobic effect of proteins, hence quantitatively giving rise to a binary linear rela- tion between HIC retention time (RT) at concentrated salting liquid and ligand-protein binding free en- ergy. Then, possible binding manners for 2. proteins of known crystal structures with hydrophobic ligands are simulated and analyzed via ICM flexible molecular docking and genetic algorithm, with re- sults greatly consistent with experimental values. By investigation, it is confirmed local hydrophobic effects of proteins and nonbinding/conformation interaction between ligand and protein both notably influence HIC chromatogram retention behaviors, mainly focusing on exposed portions on the protein surface.

关键词： hydrophobic interaction chromatography, flexible molecular docking, genetic algorithm, protein, salting-in factor

Quantitative structure activity relationships for carp kidney ATPase endpoint

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Journal of Environmental Sciences 2000年第1期12卷 88-91页

作者： XU Jing bo 1, JING Ti song 2. LU Guang hua 1, LANG Pei zhen 1 (1. Department of Environmental Sciences, Northeast normal university, Changchun 13002., China 2. Environmental and Architecture {2. college, Changchun university of Science

The IC 50 values of 2. nitroaromatics were determined by the activity of ATPase of carp ( Cyprinus carpio ) kidney in vitro, and used to develop the quantitative structure activity relationship (QSAR) with 6 descriptors of 1 X v, Σσ -, I , 1 Ka , E LUMO , log P . A best equation was obtained by multiple regression analysis -log IC 50 =1 306 Σσ -+0 657 I +0 584E LUMO +2. 852. r =0 92.). Σσ - is the sum of substituent constants. I is the indicator variable. E LUMO is the energy of the lowest unoccupied orbital. Results showed that the Σσ -, I and E LUMO were closely correlated with toxicity of nitroaromatics. Some toxicity mechanisms by nitroaromatics are also discussed in this paper.

关键词： nitroaromatic compounds carp kidney ATPase IC 50 QSAR CLC number: O62..61 Document code: A