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Effect of pH values on the extracellular polysaccharide secreted by Acidithiobacillus ferrooxidans during chalcopyrite bioleaching

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International Journal of Minerals,Metallurgy and Materials 2014年第4期21卷 311-316页

作者： Run-lan Yu Jing Liu Jian-xi Tan Wei-min Zeng Li-juan Shi Guo-hua Gu Wen-qing Qin Guan-zhou Qiu School of Minerals Processing and Bioengineering Central South University Key Laboratory of Biometallurgy Ministry of Education Hunan entry-exit inspection and quarantine bureau

The pH value plays an important role in the bioleaching of sulphide minerals. The effect of pH values on the extracellular poly-saccharide secreted by Acidithiobacillus ferrooxidans was investigated in different phases of bacterial growth during chalcopyrite bioleach-ing. It is found that extracellular polysaccharide secretion from the cells attached to chalcopyrite is more efficiently than that of the free cells in the bioleaching solution. Three factors, pH values, the concentration of soluble metal ions, and the bacterial growth and metabolism, affect extracellular polysaccharide secretion in the free cells, and are related to the bacterial growth phase. Extracellular polysaccharide secretion from the attached cells is mainly dependent on the pH value of the bacterial culture.

关键词： chalcopyrite bioleaching polysaccharides acidity Acidithiobacillusferrooxidans

Synthesis and Application of a Polymeric Crosslinking Agent for Improving Fixation of Vinylsulfone-type Dyes on Cotton by a Pad-dry-cure Process

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Journal of Donghua University(English Edition) 2006年第5期23卷 113-118页

作者：李峥嵘傅科杰孟卫东卿凤翎 College of Chemistry and Chemical Engineering Donghua University Textile products inspection Center of NingBo entry- exit inspection and quarantine bureau

A new class of novel polymeric crosslinging agent （NPCA）, which contained silane coupling group and the epoxy groups, was designed and synthesized in our laboratory. NPCA was a non-formaldehyde multifunctional crosslinking polymer. The cotton fabrics dyed with 8.0% （owf） Vinylsulpone-type dyes were treated with 3.0%- 4.0% NPCA, 0.5 mol/L potassium thiocyanate as a catalyst, then padded through two dips and two nips to reach a wet pickup of 80%- 85%, then dried at 80℃ for 2 minutes and cured in oven at 140- 150℃ for 3 minutes. Crocking fastness and fixation （%） were improved with up to 1.0 -1. 5 units, 35%- 50%, respectively. And there was little difference between the color yield of dyed fabrics before and after the treatment at certain conditions. The possible crosslinking mechanism of NPCA was also investigated. It was concluded that NPCA can improve colorfastness of cotton fabric by means of the three-dimensional network, covalent bonding and other molecular forces.

关键词： a crosslinking agent cotton fabric fastness property pad-dry-cure.

Rapid,sensitive detection of Vibrio anguillarum using loop-mediated isothermal amplification

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Chinese Journal of Oceanology and Limnology 2010年第1期28卷 62-66页

作者：高宏伟李富花张晓军王兵相建海 Institute of Oceanology Chinese Academy of Sciences Shandong entry-exit inspection and quarantine bureau of the People's Republic of China

Vibrio anguillarum is an important bacterial pathogen of aquatic organisms and a significant problem in aquatic farming. The rapid detection and identification of V. anguillarum, and other pathogens that infect marine organisms, is crucial to effective disease management. In this study, we developed a loop-mediated amplification （LAMP） assay to detect V. anguillarum in an hour in a single tube without the need for thermal cycling. Conserved regions of the metalloproteinase （empA） gene of V. anguillarum served as the targets for primer design. A fragment of the empA gene was amplified at 65℃ in the presence of the primer mixture and Bst DNA polymerase. In the optimized LAMP assay, 6.7 pg of V. anguillarum DNA could be detected. Six strains of V. anguillarum and 17 strains of non-V, anguillarum bacteria were used in this study to evaluate the species specificity of the primers. The six V. anguillarum strains gave a positive result in the LAMP assay. This method was also validated in V. anguillarum-infected fish. This LAMP method is more sensitive than PCR in the detection of V. anguillarum and shows good species specificity. The LAMP assay is therefore an effective method for the quick detection of V. anguillarum both in the laboratory and in the field.

关键词： Loop-Mediated Isothermal Amplification (LAMP) detection assay empA gene Vibrio anguillarum

Surface Microstructure and Component Changes of Chromium-resistant Enterobacter Cloacae CYS-25 Strain

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Chinese Journal of Structural Chemistry 2008年第1期27卷 15-20页

作者：马晓艳杨春鹏程扬健栗斌李冬松林璋黄丰郑晶 State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of Matter The Chinese Academy of Sciences Fuzhu entry-exit inspection and quarantine bureau

Enterobacter cloacae CYS-25 strain was isolated from a chromate plant. This bacterium was capable of resisting high hexavalent chromium concentration and reducing Cr（VI） under aerobic condition. CrO4^2- stimulated the increase of bacterial size and production of compact convex paths containing chromium on the bacterial surface. The increase of bacterial size was caused by integrative growth but not extracellular polymeric substance hyperplasia. IR and SDS-PAGE analyses showed the extracellular polymeric substance （EPS） components were mainly proteins and had no obvious changes whether the strains were induced by Cr（VI） or not. The EPS was amorphous and contained trivalent chromium. Under CrO4^2- growth condition, the extracellular substance of Enterobacter cloacae CYS-25 strains and Cr（VI） had redox reaction. The products were Cr^3＊-protein complexes which formed a piece of compact convex paths on the surface of bacteria and prevented Cr（VI） from entering into cells.

关键词： Enterobacter cloacae chromium-resistance extracellular polymeric substance(EPS)

Characterization of a Bacteriocin-Like Substance Produced from a Novel Isolated Strain of Bacillus subtilis SLYY-3

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Journal of Ocean University of China 2014年第6期13卷 995-999页

作者： LI Junfeng LI Hongfang ZHANG Yuanyuan DUAN Xiaohui LIU Jie College of Chemical Engineering Qingdao University of Science & Technology Yantai entry-exit inspection and quarantine bureau

In the present research, the strain SLYY-3 was isolated from sediments of Jiaozhou Bay, Qingdao, China. The strain SLYY- 3, which produced a bacteriocin-like substance （BLS）, was characterized to be a strain of Bacillus subtillis by biochemical profiling and 16S rDNA sequence analysis. It is the first time to report that Bacillus subtilis from Jiaozhou Bay sediments could produce a BLS. The BLS of B. subtillis SLYY-3 exhibited strong inhibitory activity against gram-positive bacteria （including Staphylococcus aureus and B. subtillis） and some fimgi （including Penicillium glaucum, Aspergillus niger and Aspergillus flavus）. The antimicrobial activity was detected from culture in the exponential growth phase and reached its maximum when culture entered into stationary growth phase. It was thermo-tolerant even when being kept at 100~C for 60 min without losing any activity and stable over a wide pH range from 1.0 to 12.0 while being inactivated by proteolytic enzyme and trypsin, indicating the proteinaceous nature of the BLS. The BLS was purified by precipitation with hydrochloric acid （HC1） and gel filteration （Sephadex G-100）. SDS-PAGE analysis of the extracellular peptides of SLYY-3 revealed a bacteriocin-like protein with a molecular mass of 66 kDa. Altogether, these characteristics indicate the potential of the BLS for food industry as a protection against pathogenic and spoilage microorganisms.

关键词： bacteriocin-like substance Bacillus subtillis SLYY-3 antimicrobial activity food protection purification

Individualized management of pregnant women with high hepatitis B virus DNA levels

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World Journal of Gastroenterology 2014年第34期20卷 12056-12061页

作者： Zhao Zhang Chao Chen Zhe Li Ying-Hua Wu Xiao-Min Xiao Department of Obstetrics and Gynecology The First Affiliated Hospital of Jinan University Zhuhai entry-exit inspection and quarantine bureau

Hepatitis B is a major health concern in the Asia-Pacific region, and is endemic in China, Southeast Asia, and Africa. Chronic hepatitis B virus (HBV) infection may cause hepatic cirrhosis and liver cancer. It is estimated that there are more than 350 million chronic HBV carriers worldwide, of whom approximately one quarter will die of chronic hepatitis B-related liver diseases. HBV is transmitted horizontally through blood and blood products or by sexual transmission, and vertically from mother to infant. Perinatal infection is the predominant mode of transmission in countries with a high prevalence of hepatitis B surface antigen (HBsAg) carriage, and perinatal transmission leads to high rates of chronic infection. Therefore, it is important to prevent the mother-to-child transmission (MTCT) of HBV. Research has shown that pregnant women with high HBV DNA levels have an increased risk of MTCT. However, most of the obstetrics guidelines do not make a distinction between pregnant women with high HBV DNA levels and those who are HBsAg positive only. This review addresses the management of pregnant women with high levels of HBV viremia, in terms of antiviral therapy, use of hepatitis B immunoglobulin (HBIG), the combined application of hepatitis B vaccine and HBIG, choice of delivery mode and feeding practices. (C) 2014 Baishideng Publishing Group Inc. All rights reserved.

关键词： Hepatitis B virus Hepatitis B virus DNA High level Management Pregnancy

Ordered proposition fusion based on consistency and uncertainty measurements

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Science China(Information Sciences) 2017年第8期60卷 117-135页

作者： Dayou LIU Yungang ZHU Ni NI Jie LIU College of Computer Science and Technology Jilin University Key Laboratory of Symbolic Computation and Knowledge Engineering of Ministry of Education Jilin University Beijing entry-exit inspection and quarantine bureau

The fusion of ordered propositions is an important and widespread problem in artificial intelligence,but existing fusion methods have difficulty handling the fusion of ordered propositions. In this paper, we propose a solution based on consistency and uncertainty measurements. The main contributions of this paper are as follows. First, we propose the concept of convexity degree, mean, and center of basic support function to comprehensively describe the basic support function of ordered propositions. Second, we introduce entropy as a measure of uncertainty in the basic support function of ordered propositions. Third, we generalize the indeterminacy of the basic support function and propose a novel method to measure the consistency between two basic support functions. Finally, based on the above researches, we propose a novel algorithm for fusing ordered propositions. Theoretical analysis and experimental results demonstrate that the proposed method outperforms state-of-the-art methods.

关键词： uncertainty processing ordered proposition evidence theory dempster rule of combination information fusion

Preparation of high selective molecularly imprinted polymers for tetracycline by precipitation polymerization

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Chinese Chemical Letters 2007年第12期18卷 1535-1538页

作者： Tao Jing Xiao Dan Gao Peng Wang Yan Wang Yan Fei Lin Xu Chen zong Yi Kai Zhou Su Rong Mei MOE Key Lab of Environment and Health Institute of Environmental Medicine TongJi Medical College Huazhong University of Science and Technology Wuhan 430030 China hubei entry-exit inspection and quarantine bureau of prc Wuhan 430022 China

High selective molecularly imprinted polymers （MIPs） for tetracycline have been prepared by precipitation polymerization. Effects of monomer and solvent, the ratio of monomer and template and the characterization of the polymer were investigated by frontal chromatography and selectivity experiment. The results clearly indicated that the polymer, which had the highest molecular recognition abilities for tetracycline antibiotics, had been received.

关键词： Precipitation polymerization Tetracycline antibiotics Molecularly imprinted polymers (MIPs) HPLC

Trace analysis of anions in organic matrices by ion chromatography coupled with a novel reversed-phase column for on-line sample pretreatment

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Chinese Chemical Letters 2011年第4期22卷 461-464页

作者： Ying Ying Zhong Wen Fang Zhou Xue Ling Zeng Ming Li Ye Yan Zhu Department of Chemistry Zhejiang UniversityHangzhou 310028China Ningbo entry-exit inspection and quarantine bureau Ningbo 315012China

An ion chromatography（IC） system coupled with on-line column-switching technique was used to determine anions ofμg/g levels in organic chemicals of analytical reagent grade.A novel polystyrene-divinylbenzene-carbon nanotube（PS-DVB-CNT） stationary phase was utilized for matrix elimination.A calibration study was conducted by preparing and analyzing eight concentrations（between 10 and 5000μg/L） of eight standards in deionized *** linearity was between 0.9978 and *** the detection limits ranged from 1.54μg/L to 10.02μg/L.A spiking study was performed on two representative organic *** recoveries were between 84.3%and 119.6%.

关键词： Ion chromatography Column switching Trace anions Organic matrix Polymer stationary phase