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Effects of bacterially produced precipitates on the metabolism of sulfate reducing bacteria during the bio-treatment process of copper-containing wastewater

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Science china Chemistry 2010年第12期53卷 2608-2615页

作者： SHENG YuXing,CAO HongBin,LI YuPing & ZHANG Yi national Engineering laboratory for Hydrometallurgical Cleaner Production Technology key laboratory of Green Process and Engineering,Institute of Process Engineering,chinese academy of sciences,beijing 100190,china national Engineering laboratory for Hydrometallurgical Cleaner Production Technology key laboratory of Green Process and Engineering Institute of Process Engineering Chinese Academy of Sciences Beijing China

A large volume of bacterially produced precipitates are generated during the bio-treatment of heavy metal *** composition of the bacterially produced precipitates and its effects on sulfate reducing bacteria (SRB) in copper-containing waste stream were evaluated in this *** elemental composition of the microbial precipitate was studied using electrodispersive X-ray spectroscopy (EDX),and it was found that the ratio of S:Cu was *** with the results of copper distribution in the SRB metabolism culture,which was analyzed by the sequential extraction procedure,copper in the precipitates was determined as covellite (CuS).The bacterially produced precipitates caused a decrease of the sulfate reduction rate,and the more precipitates were generated,the lower the sulfate reduction rate *** particle sizes of bacterially generated covellite were ranging from 0.03 to 2 m by particles size distribution (PSD) analysis,which was smaller than that of the SRB *** electron microscopy (TEM) analysis showed that the microbial covellite was deposited on the surface of the *** effects of the microbial precipitate on SRB metabolism were found to be weakened by increasing the precipitation time and adding microbial polymeric substances in later *** results provided direct evidence that the SRB activity was inhibited by the bacterially produced covellite,which enveloped the bacterium and thus affected the metabolism of SRB on mass transfer.

关键词： sulfate reducing bacteria covellite heavy metal wastewater

Present status and development on biological nitrogen fixation research in china

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chinese Science Bulletin 2003年第10期48卷 954-960页

作者： SHEN Shihua & JING Yuxiang key laboratory of Photosynthesis and Plant-Environment MolecularPhysiology, Institute of Botany, chinese academy of sciences, beijing 100093, china key laboratory of Photosynthesis and Plant-Environment Molecular Physiology Institute of Botany Chinese Academy of Sciences Beijing 100093 China

This presentation introduces the advances inbiological nitrogen fixation research abroad, in particular,describes the great progress and achievements on itsresearch in china as follows: collection of rhizobial resources and establishment of the largest database of Rhizobium inchina, correction and development of Rhizobium taxonomy in international; discovery of a couple of nif genes,identification and unification of linkage among the nif gene operons of Klebsiella pneumoniae, finding of regulative mechanism of positive regulation nif gene and its sensitivity to oxygen, temperature; finding of the activity of nodulation gene nodD3 product in Sinorhizobium meliloti which is notcontrolled by flavonoid produced from its host alfalfa;finding of the association between expression of genes coding the products for carbon utilization and nitrogen metabolism and their regulations; chemical synthesis of nodulationfactor of Sinorhizobium meliloti; constructions of engineered nitrogen fixers and utilization in practice based on theresearch of gene expression and regulation; chemicalsimulation of the structure and function of nitrogenase and bringing forward the model of nitrogenase active center for the first time in international and synthesis of modelcompounds which were paid attention by colleagues abroad. Finally, the development of nitrogen fixation research inchina in future has been put forward, suggesting that the nifgene regulation and its role in providing crops with nitrogen element, signal transduction and molecular interactions between Rhizobium and legume, coupling between carbonand nitrogen metabolisms, nitrogen fixation andphotosynthesis, and functional genomics of nitrogen-fixing nodule symbiosis, etc., would be actively worked on.

关键词：现状发展生物固氮技术中国固氮酶基因表达微生物植物相互作用化学模型

Elemental and isotopic compositions of the hydrothermal sulfide on the East Pacific Rise near 13°N

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Science china Earth sciences 2010年第2期53卷 253-266页

作者： ZENG ZhiGang1,CHEN DaiGeng1,2,YIN XueBo1,WANG XiaoYuan1,ZHANG GuoLiang1,2 & WANG XiaoMei1,2 1 Seafloor Hydrothermal activity laboratory of the key laboratory of Marine Geology and Environment,Institute of Oceanology,chinese academy of sciences,Qingdao 266071,china 2 Graduate School of chinese academy of sciences,beijing 100049,china Seafloor Hydrothermal activity laboratory of the key laboratory of Marine Geology and Environment Institute of Oceanology Chinese Academy of Sciences Qingdao China Graduate School of chinese academy of sciences Beijing China

The mineralogical,elemental,and isotopic characteristics of a hydrothermal sulfide sample from one dredge station (12°42.30’N,103°54.48’W,water depth 2655 m) on the East Pacific Rise near 13°N were *** hydrothermal sulfide was composed mainly of sphalerite,chalcopyrite,and pyrite and was a Zn-rich sulfide;in layer ep-s-1,goethite formed by secondary oxidation was *** concentrations of rare elements,such as Li (0.15×10-6-0.30×10-6),Be (0.01×10-6-0.05×10-6),Zr (73.8×10-9-1344×10-9),Nb (8.14×10-9-64.7×10-9),Hf (2.54×10-9-28.0×10-9),and Ta (0.203×10-9-1.21×10-9),were far lower in the hydrothermal sulfide than in the ocean crust,whereas the content of Au was higher and the contents of Co,Ni,Sr,Cs,Ba,Bi,and U were *** correlations between Zn and Cr,Cd and Ga,Cu and P,P and In (R2 > 0.8) were positive,whereas those between Zn and Fe,Cu,and Ba (R2 > 0.8) were distinctly *** low-temperature mineral assemblages to high-temperature mineral assemblages,the spatial distributions of dispersive and rare elements (***,Li,Cs) in the hydrothermal sulfide displayed corresponding *** variations observed in some elements (e.g.,Cd,Cs,P) are controlled by Zn,Fe,and Cu sulfides,*** weathering accounts for the enrichment of V,Mn,and rare earth elements (REE) in the henna sulfide-oxidation layer that bears the secondary oxide mineral,leading to identical REE patterns for this layer (ep-s-1) and *** weathering also distinctly affects the correlations between the element ratios of the hydrothermal *** high-temperature mineral assemblages to low-temperature mineral assemblages,Fe content and δ 34S value of the hydrothermal sulfide increase gradually,and Zn content and lead isotopic ratios decrease gradually on the contrary,which indicate the influences of seawater on elements and the sulfur and lead isotopic compositions enhance gradually during the formation of hydrothermal sulfides.

关键词： variation element isotopic composition hydrothermal sulfide East Pacific Rise 13oN

Cloning,expression and characterization of a nucleoside diphosphate kinase (NDPK) gene from tobacco

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Progress in Natural Science:Materials International 2007年第08期17卷 906-912页

作者： Zhou Qiyun~(1,2**) Xie Zongming~(1**) Zhang Zhigang~1 Cao Yangrong~1 Zhang jinsong~(1***) Chen Shouyi~(1***) (1.national key laboratory of Plant Genomics,Institute of Genetics and Developmental Biology,chinese academy of sciences,beijing100101,china 2.Graduate University of chinese academy of sciences,beijing 100039,china) national key laboratory of Plant Genomics Institute of Genetics and Developmental Biology Chinese Academy of Sciences Beijing 100101 China Graduate University of chinese academy of sciences Beijing 100039 China

Nucleoside diphosphate kinase (NDPK) is a housekeeping enzyme that maintains the intracellular levels of all (d)NTPs used in biosynthesis except *** we report that a full-length cDNA encoding nucleoside diphosphate kinase (NDPK) was cloned us- ing yeast two-hybrid approach.A tobacco NDPK gene was obtained and designated as ***1 is 704 bp in length and en- codes a putative 16.2 kD protein of 148 amino *** analysis showed that NtNDPK1 is highly homologous to other plant NDPK genes and identified as type I (NDPK1).RNA-gel blot analysis showed that there was no significant difference of NtNDPK1 ex- pression in roots,stems,leaves and *** expression of NtNDPK1 was induced by ABA and PEG and repressed by NaCl,but not significantly affected by Paraquat,wounding and low temperature (4℃) treatments,indicating that NtNDPK1 may play a certain role in response to abiotic *** vitro phosphorylation assay demonstrated that NtNDPK1 had autophosphoryLation activity.

关键词： abiotic stress autophosphorylation activity NtNDPK1 tobacco yeast two-hybrid

Synchrotron peak luminosity,black hole mass and Eddington ratio for SDSS flat-spectrum radio quasars

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Science china(Physics,Mechanics & Astronomy) 2010年第S1期53卷 202-206页

作者： GU MinFeng1 & CHEN ZhaoYu1,2 1 key laboratory for Research in Galaxies and Cosmology,Shanghai astronomical Observatory,chinese academy of sciences,Shanghai 200030,china 2 Graduate University of the chinese academy of sciences,beijing 100049,china key laboratory for Research in Galaxies and Cosmology Shanghai Astronomical Observatory Chinese Academy of Sciences Shanghai China Graduate University of the chinese academy of sciences Beijing China

For a sample of 185 flat-spectrum radio quasars(FSRQs) constructed from the SDSS DR3 quasar catalog,we found a significant correlation between the synchrotron peak luminosity and both the black hole mass and Eddington *** implies that the physics of its jet formation is not only tightly related with the black hole mass,but also with the accretion *** verify that the synchrotron peak luminosity can be a better indicator of jet emission than 5 GHz luminosity,through comparing the relationships between each of these two parameters and both black hole mass and Eddington *** fundamental plane of black hole activity for our FSRQs is established as Lr ∝ L0x.80 ± 0.06 Mbh -0.04 ± 0.09 with a weak dependence on black hole mass,however,the scatter is significant.

关键词： black hole physics galaxies:active galaxies:nuclei quasars:emission lines quasars:general

A cyclic behavior of CME accelerations for accelerating and decelerating events

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Research in Astronomy and Astrophysics 2009年第10期9卷 1165-1172页

作者： Peng-Xin Gao Ke-Jun Li national astronomical observatories / Yunnan Observatory Chinese Academy of Sciences Kunming 650011 China Graduate University of chinese academy of sciences Beijing 100049 China

We investigate the cyclic evolutionary behavior of CME accelerations for accelerating and decelerating CME events in cycle 23 from 1997 January to 2007 December. It is found that the absolute values of semiannual mean accelerations of both accelerating and decelerating CME events roughly wax and wane in a cycle, delaying the sunspot cycle in time phase. We also investigate the semiannual number of CMEs with positive and neg- ative acceleration and find that there are more decelerating CME events than accelerating CME events during the maximum period of a cycle （about three years）, but there are more accelerating CME events than decelerating CME events during the rest of the time interval of the cycle. Our results seem to suggest that the different driving mechanisms may be acting accelerate and decelerate CME events; for accelerating CME events, the propelling force （Fp） statistically seems to play a significant role in pushing CMEs outward; for decelerating CME events, the drag （Fd） statistically seems to play a more effective role in determining CME kinematic evolution in the outer corona. During the maximum period of a cycle, because of the V^2 dependence, Fd is generally stronger; because of the magnetic field dependence, Fp is also generally stronger. Thus, the absolute values of both the negative and positive accelerations are generally larger during that time. Because of the V^2 dependence, Fd may be more effective during the maximum period of a cycle. Hence, there are more decelerating CME events than accelerating CME events during that time. During the minimum time interval of a cycle, CMEs have relatively small speeds, and Fp may be more effective. Therefore, there are more accelerating CME events than decelerating CME events during that time.

关键词： Sun corona -- Sun coronal mass ejections (CMEs)

SYNTHESIS AND CHARACTERIZATION OF BIS-[2-[[(2-ALKOXYPHENYL)IMINO]METHYL]-PHENOLATO-O,N,O]NICKEL(II)COMPLEXES AND THEIR NORBORNENE POLYMERIZATION

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chinese Journal of Polymer Science 2005年第6期23卷 619-626页

作者： Dong-heng Zhang Su-yun Jie Hai-jian Yang Fei Chang and Wen-hua Sun key laboratory of Engineering Plastics,Institute of Chemistry,chinese academy of sciences,beijing 100080,china key laboratory of Engineering Plastics Institute of Chemistry Chinese Academy of Sciences Beijing 100080 China

A series of salicylaldimines, synthesized in high yield via microwave-assisted condensation of salicylaldehyde and 2-alkoxyaniline were allowed to react with nickel chloride to form six-coordinated nickel complexes. These nickel complexes were carefully characterized, and the solid structure of la was elucidated by X-Ray diffraction. Activated with MAO, the nickel complexes showed good activity for homopolymerization of norbornene. Reaction parameters, such as the ratio of nickel precursor to MAO, monomer concentration, reaction time and the reaction temperature, as well as the nature of the ligands were found to have significant effects on the catalytic activity and some properties of the resulting polynorbornene.

关键词： Salicylaldirnine Nickel complex Norbornene Vinyl polymerization

Origin of a native sulfur chimney in the Kueishantao hydrothermal field, offshore northeast Taiwan

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Science china Earth sciences 2007年第11期50卷 1746-1753页

作者： ZENG ZhiGang1, LIU ChangHua1,2, CHEN ChenTung A3, YIN XueBo1, CHEN DaiGeng1,2, WANG XiaoYuan1,2, WANG XiaoMei1,2 & ZHANG GuoLiang1,2 1 Seafloor Hydrothermal activity laboratory of the key laboratory of Marine Geology and Environment, Institute of Oceanology, chinese academy of sciences, Qingdao 266071, china 2 Graduate University of chinese academy of sciences, beijing 100049, china 3 Institute of Marine Geology and Chemistry, national Sun Yat-Sen University, Kaohsiung 804, Taiwan, china Seafloor Hydrothermal activity laboratory of the key laboratory of Marine Geology and Environment Institute of Oceanology Chinese Academy of Sciences Qingdao China Graduate University of chinese academy of sciences Beijing China Institute of Marine Geology and Chemistry National Sun Yat-Sen University Kaohsiung China

Analyses of rare earth and trace element concentrations of native sulfur samples from the Kueishantao hydrothermal field were performed at the Seafloor Hydrothermal activity laboratory of the key Labo-ratory of Marine Geology and Environment, Institute of Oceanology, chinese academy of sciences. Using an Elan DRC II ICP-MS, and combining the sulfur isotopic compositions of native sulfur samples, we studied the sources and formation of a native sulfur chimney. The results show, when comparing them with native sulfur from crater lakes and other volcanic areas, that the native sulfur content of this chimney is very high (99.96%), the rare earth element (REE) and trace element constituents of the chimney are very low (ΣREE<21×10?9), and the chondrite-normalized REE patterns of the native sulfur samples are similar to those of the Kueishantao andesite, implying that the interaction of subseafloor fluid-andesite at the Kueishantao hydrothermal field was of short duration. The sulfur isotopic compo-sitions of the native sulfur samples reveal that the sulfur of the chimney, from H2S and SO2, originated by magmatic degassing and that the REEs and trace elements are mostly from the Kueishantao ande-site and partly from seawater. Combining these results with an analysis of the thermodynamics, it is clear that from the relatively low temperature (<116 ℃ ), the oxygenated and acidic environment is favorable for formation of this native sulfur chimney in the Kueishantao hydrothermal field.

关键词： origin,native sulfur chimney,Kueishantao hydrothermal field,northeast Taiwan

Validity of the Bouchet's complementary relationship at 102 observatories across china

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Science china Earth sciences 2009年第5期52卷 708-713页

作者： YU JingJie1,2,ZHANG YongQiang3,LIU ChangMing1,2 1 Institute of Geographic sciences and Natural Resources Research,chinese academy of sciences,beijing 100101,china 2 key laboratory of Water Cycle and Related Land Surface Processes,chinese academy of sciences,beijing 100101,china 3 CSIRO Land and Water,PO Box 1666,Canberra ACT 2601,Australia Institute of Geographic sciences and Natural Resources Research Chinese Academy of Sciences Beijing China key laboratory of Water Cycle and Related Land Surface Processes Chinese Academy of Sciences Beijing China CSIRO Land and Water Canberra Australia

Bouchet in 1963 hypothesized that for large homogeneous land surface with minimum advection of heat and moisture,there exists a 1:1 complementary relationship of potential and actual evaporation coupled through land-atmosphere *** complementary relationship has been widely used to estimate regional actual evaporation and explain the pan evaporation *** examine the standardized potential evaporation(potential evaporation divided by wet environment evaporation) at 102 observatories at different elevations across ***,the relationship is appropriate at the low elevations(solar *** a result,at the high elevations(over 1000 m),the excess energy resulted by limited moisture availability is not enough to be converted into drying power of the *** result suggests that the complementary relationship is asymmetric at the high elevations.

关键词： evaporation complementary relationship elevation china