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Biostimulation-enhanced Biodegradation of Nitrobenzene in Contaminated Groundwater

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Chemical Research in Chinese Universities 2012年第5期28卷 818-823页

作者： AN Yong-lei zhang lan-ying LIU Na zhang Lei GAO Huan-fang Key Laboratory of Groundwater Resources and Environment Ministry of EducationJilin UniversityChangchun 130021P R.China Key Laboratory of Wetland Ecology and Environment Northeast Institute of Geography and AgroecologyChinese Academy of SciencesChangchun 130012P.R.China

In this study, biostimulation technology was used for bioremediation of nitrobenzene-contaminated groundwater by adding a mixture of lactose and phosphate, peptone, and beef extract. During the process of biostimulation, the remediation effectiveness, microbial dehydrogenase activities and microbial densities were investigated; the varieties of microbial community structure and composition were analyzed by polymerase chain reaction-denaturing gradient gel electrophoresis（PCR-DGGE） technique and the relative abundances of nitrobenzene-degrading gene（nbzA） were determined by fluorescence quantitative real-time PCR（RT-PCR）. Findings show that the removal rate of nitrobenzene in groundwater could reach about 60% by biostimulation with lactose and phosphate, 70% with peptone and 68% with beef extract. The microbial dehydrogenase activities and microbial densities were all improved obviously via biostimulation. The results of PCR-DGGE show that the microbial diversities were improved, and more than ten kinds of dominant microorganisms were detected after biostimulation. RT-PCR results show that the relative abundances of nbzA gene of microbes in groundwater were increased significantly, which indicated that biostimulation actually enhanced the growth of nitrobenzene-degrading bacteria. Therefore, biostimulation is a cost-effective and feasible bioremediation technique for nitrobenzene-contaminated groundwater.

关键词： Nitrobenzene Groundwater Biostimulation Polymerase chain reaction-denaturing gradient gel electro-phoresis(PCR-DGGE) Real-time polymerase chain reaction(RT-PCR)

Preparation of Bio-beads and Their Atrazine Degradation Characteristics

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Chemical Research in Chinese Universities 2011年第3期27卷 407-412页

作者： BI Hai-tao zhang lan-ying LIU Na ZHU Bo-lin College of Environment and Resources Jilin University Changchun 130026 P. R. China

Screened atrazine-mineralizing bacterium―Pseudomonas W4 was embedded inside an improved PVA- H3BO3 embedment matrix to make bio-beads to degrade atrazine. The atrazine degradation characteristics were studied. The preparation procedure of bio-beads was as follows：（1） preparing a mixture of 100, 12.5, 10, 1.5 and 1 g/L PVA, bentonite（Ca）, activated carbon powder, sodium alginate and centrifuged Pseudomonas W4 bacterium, respectively; （2） the mixture was dropped into a gently stirred cross linker solution（pH=6.7） and cured at 10 °C for 24 h. The optimal atrazine degradation conditions by bio-beads were as follows： pH=7, the auxiliary carbon source was glucose, and the concentration of glucose was greater than 325 mg/L. The bio-beads demonstrated stronger tolerance ability than the free microorganism to the increase of PCBs, hydrogen ion and hydroxide ion. SEM images show the uniform distribution of the microorganism inside bio-beads and the porous cross-linked structure of bio-beads which provides excellent mass transfer capacity.

关键词： Atrazine Polyvinyl alcohol(PVA) Embedment Bio-bead

Changes in Texture and Retorting Yield in Oil Shale During Its Bioleaching by Bacillus Mucilaginosus

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Chemical Research in Chinese Universities 2013年第2期29卷 294-298页

作者： zhang Xue-qing REN He-jun LIU Na zhang lan-ying ZHOU Rui Key Lab of Groudwater Resources and Environment Ministry of Education College of Environment and Resources Jilin University Changchun 130012 P. R. China

Bioleaching of oil shale by Bacillus mucilaginosus was carried out in a reaction column for 13 d. The pH value of the leaching liquor decreased steadily from 7.5 to 5.5 and the free silicon dioxide concentration reached approximately 200 mg/L in it. Scanning electron microscopy（SEM） observations revealed that a mass of small particles separated from the matrix of oil shale. Energy dispersive spectrometry（EDS） analysis implied that the total content of Si,O, A1 was decreased in the particle area of the matrix. These facts indicate that the silicate was removed, leading to the structural transformation of oil shale. Comparison of the shale oil yields before and after bioleaching illustrated that approximately 10% extra shale oil was obtained. This finding suggests that the demineralisation of the oil shale by silicate bacteria improves shale oil yield.

关键词： Oil shale Bacillus mucilaginosus Bioleaching Shale oil yield

Two New Flavonol Glycosides from Bridelia tomentosa

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Chinese Chemical Letters 2006年第10期17卷 1339-1342页

作者： Shi Hui SHU Jin lan zhang ying Hong WANG Hai Lin QIN Institute of Materia Medica Chinese Academy of Medical Sciences and Peking Union Medical College Key Laboratory of Bioactive Substances and Resources Utilization of Chinese Herbal Medicine Ministry of Education Beijing 100050

Two new flavonol glycosides, tamarixetin 3-O-β-D-xylopyranosyl-（1-2）-α-L-ribopyranoside （1） and tamarixetin 3-O-α-L-ribopyranoside （2） were isolated from the leaves of Bridelia tomentosa. Their structures wer... 详细信息

关键词： Bridelia tomentosa flavonol glycosides tamarixetin 3-O-β-D-xylopyranosyl-(1-2)-α-L-ribopyranoside tamarixetin 3-O-α-L-ribopyranoside.

Trichloroethylene Dechlorination by Copper-contained Zero-valent Iron Slurry

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Chemical Research in Chinese Universities 2013年第6期29卷 1173-1179页

作者： LI Hai-jun QIU Hua zhang lan-ying LIU Na ZHU Bo-lin Key Laboratory of Groundwater Resources and Environment Ministry of EducationJilin University Changchun 130021 P.R.China Liaoyang Environmental Inspection Office Liaoyang 111000 P.R.China

Zero valent iron technology has been widely used for treating contaminated wastewater these years. However, it always results in inefficiency in the processes of drying and storage due to oxidation and passivation. This could be avoided by in situ synthesized zero valent iron slurry in an emergency if it possesses the same performance as zero valent iron. In this study, iron slurry was synthesized and directly used for dechlorinating trichloroe- thylene to measure its degradation efficiencies and properties. Results show that 2%（mass ratio） copper-contained zero-valent iron slurry exhibits the optimal performance compared with the other iron slurries. Batch experiments in- dicate that factors such as the concentration of trichloroethylene, pH, dissolved oxygen and equilibrium to a certain extent affect the reduction oftrichloroethylene by 2%（mass ratio） copper-contained zero-valent iron slurry. Persistent, high-efficiency degradation performance could last 7 cycles. These demonstrate that the application of coppercontained zero-valent iron slurry in treating trichloroethylene-contained wastewater is realistic.

关键词： Zero valent iron Copper-contained zero-valent iron slurry Trichloroethylene Dechlorination

Molecular Cloning and Characterization of a New Cold-active Extradiol Dioxygenase from a Metagenomic Library Derived from Polychlorinated Biphenyl-contaminated Soil

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Chemical Research in Chinese Universities 2012年第4期28卷 666-671页

作者： REN He-jun LU Yang ZHOU Rui DAI Chun-yan WANG Yah zhang lan-ying Key Laboratory of Groudwater Resources and Environment Ministry of EducationCollege of Environment and ResourcesJilin UniversityChangehun 130021P.R.China Jilin Academy of Agricultural Sciences Changehun 130033P.R.China Institute of Virology and AIDS Research the First Hospital of Jilin UniversityChangchun 130061P.R.China

To find new extradiol dioxygenases（EDOs,EC 1.***.11.2）,a metagenomics library was constructed from polychlorinated biphenyl-contaminated soil and was screened for some dioxygenase with aromatic ring cleavage activity.A novel EDO,designated as BphC_A,was identified and heterologously expressed in Escherichia *** deduced amino acid sequence of BphC_A exhibited a homology of less than 60% with other known *** analysis of BphC_A suggests that the protein is a novel member of the EDO *** enzyme exhibits higher substrate affinity and catalytic efficiency toward 3-methylcatechol than toward 2,3-dihydroxybiphenyl or catechol,the preferred substrate of other known *** optimum activity of purified BphC_A occurred at pH=8.5 and 35 °C,and BphC_A showed more than 40% of its initial activity at 5 °*** activity of purified BphC_A was significantly induced by Mn^2＋ and slightly reduced by Al^3＋,Cu^2＋ and Zn^2＋.

关键词： Extradiol dioxygenase Metagenome Cold-active enzyme Gene cloning Functional characterization

Tryptophan Modification and Fluorescence Spectrum of Hyaluronidase

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Chinese Chemical Letters 2005年第11期16卷 1492-1494页

作者： Li Rong TENG Yu Zhuo CHU Xiao Ping zhang Xiao Kun YU Jing WANG Song HAN Bo Xun zhang Hao FAN lan ying LIU College of Life Science Jilin University Changchun 130023

Tryptophan residues in hyaluronidase （HAase） were modified by N-bromosuccinimide （NBS）, the results indicated that there were eleven tryptophan residues in HAase, one of which was exposed and essential for the activity of the enzyme. The study on fluorescence quenching showed that KI could not quench all of the fluorescence from Trp residues in HAase, while acrylamide （Acr） could quench almost all of the fluorescence from Trp residues in HAase. The collisional quenching constants （KD） of HAase at different concentrations of Acr were calculated in terms of Stern-Volmer equation. The results implied that some of the Trp residues were buried in the interior of HAase and the Trp residue on the surface of HAase was not located in the hydrophobic pocket.

关键词： Hyaluronidase (HAase) tryptophan (Trp) fluorescence spectrum.

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航天扩频测控系统中伪码捕获方法研究

电子学报 2011年第6期39卷 1471-1476页

作者：章兰英袁嗣杰陈源装备指挥技术学院测控工程研究中心北京101416

针对航天扩频测控系统的捕获需求,提出一种能够降低谱峰衰减且具有较高频率估计精度的FFT伪码捕获方法.在部分匹配滤波过程中采用汉宁窗对数据加权后再累加,以减小谱峰衰减.采用插值FFT估计多普勒频率,以提高频率估计精度,根据不同测控... 详细信息

针对航天扩频测控系统的捕获需求,提出一种能够降低谱峰衰减且具有较高频率估计精度的FFT伪码捕获方法.在部分匹配滤波过程中采用汉宁窗对数据加权后再累加,以减小谱峰衰减.采用插值FFT估计多普勒频率,以提高频率估计精度,根据不同测控环境下伪码捕获的特点,分析比较了抛物线插值法和改进的Rife法两种插值算法.理论分析和仿真结果表明,改进方法能够减小FFT输出的峰值衰减,提高多普勒频率估计精度.

关键词：扩频测控伪码捕获部分匹配滤波抛物线插值 Rife算法

Study on Reductive Dechlorination of PCBs in Groundwater by Fe/Zn Bimetal

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Meteorological and Environmental Research 2012年第7期3卷 42-45,50页

作者： LIU Yuan-yuan zhang lan-ying QIU Ming-ying REN He-jun DU Jun Key Laboratory of Groundwater Resources and Environment Ministry of EducationJilin UniversityChangchun 130026China

[Objective] The research aimed to study reductive dechlorination effect of PCBs in groundwater by Fe/Zn bimetal. [Method] Fe/Zn bi- metal as reduction system, PCBs degradation ratio as inspected index, degradation effect of PCBs by Fe/Zn bimetallic system when adding self- made hydroxypropyl-β-cyclodextdn （HP-β-CD） was studied. Meanwhile, we investigated the influences of loading ratio and Fe-Zn dosage on PCBs dechlorination. [ Result] PCBs was significantly solubilized by the synthesized HP-β-CD. With increase of the HP-β-CD concentration, the apparent solubility of PCBs increased linearly, forming 1：1 inclusion complex. When Fe-Zn dosage was 10 g, and mass fraction of Zn was 7%, the dechlori- nation efficiency of 321 μg/L PCBs was 47.6% after degrading for 7 d at 10 ℃. [ Condusion] The research provided theoretical guiding for in situ remediation of the qroundwater contaminated bv PGBs.

关键词： HP-β-CD Dechlorination PCBs Fe/Zn bimetal China