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Gene expression and molecular characterization of a thermostable trehalose phosphorylase from Thermoanaerobacter tengcongensis

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Science china(Life sciences) 2005年第3期48卷 221-227页

作者： REN Yuanyuan 1,2., DAI Xiuyu 1 , ZHOU Jian 1 , LIU Jingfang 1 , PEI Huadong 1,2.& XIANG Hua 1 1. State Key Laboratory of Microbial Resources and Center for Molecular Microbiology, institute of Microbiology, chinese Academy of {2., Beijing 100080,{3. 2. Graduate School of chinese Academy of {2., Beijing 10003.,{3. 1. State Key Laboratory of Microbial Resources and Center for Molecular Microbiology Institute of Microbiology Chinese Academy of Sciences 100080 Beijing China 2. Graduate School of chinese Academy of sciences 100037 Beijing China

A gene encoding the trehalose phosphorylase (TreP), which reversibly catalyzes trehalose degradation and synthesis from α-glucose-1-phosphate (α-Glc-1-P) and glucose, was cloned from Thermoanaerobacter tengcongensis and successfully expressed in Escherichia coli. The overexpressed TreP, with a molecular mass of approximately 90 kDa, was determined by SDS-PAGE. It catalyzes trehalose synthesis and degradation optimally at 70℃ (for 3. min), with the optimum pHs at 6.0 and 7.0, respectively. It is highly thermostable, with a 77% residual ac- tivity after incubation at 50℃ for 7 h. Under the optimum reaction conditions, 50 μg crude en- zyme of the TreP is able to catalyze the synthesis of trehalose up to 11.6 mmol/L from 2. mmol/L α-Glc-1-P and 12. mmol/L glucose within 3. min, while only 1.5 mmol/L out of 2.0 mmol/L tre- halose is degraded within the same time period. Dot blotting revealed that the treP gene in T. tengcongensis was upregulated in response to {2. stress but downregulated when trehalose was supplied. Both results indicate that the dominant function of the T. tengcongensis TreP is catalyzing trehalose synthesis but not degradation. Thus it might provide a novel route for indus- trial production of trehalose.

关键词： gene expression, Thermoanaerobacter tengcongensis, trehalose phosphorylase, dot blot.

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Effect of an Alien Species Spartina alterniflora Loisel on Biogeochemical Processes of Intertidal Ecosystem in the Jiangsu Coastal Region,china

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Pedosphere 2008年第1期18卷 77-85页

作者： ZHOU Hong-Xia LIU Jin-E ZHOU Jun QIN Pei Life Science School Nanjing University Nanjing 210093 （China） Kunming institute of Botany Chinese Academy of Sciences Kunming 650204 （China）

Spartina alterniflora Loisel, a species vegetating in intertidal flats along the eastern coast of the United States, was introduced in china almost 3. years ago and has become an urgent topic due to its invasiveness in the coastal zone of china. The impacts of this alien species S. alterniflora on intertidal ecosystem processes in the Jiangsu coastland were investigated by comparing the sediment nutrient availability and trace element concentration characteristics in a mud flat and those of a four-year old Spartina salt marsh that had earlier been a mudflat. At each study site, fifteen plots were sampled in different seasons to determine the sediment characteristics along the tidal flats. The results suggested that Spartina salt marsh sediments had significantly higher total N, available P, and water content, but lower pH and bulk density than mudflat sediments. Sediment salinity, water content, total N, organic C, and available P decreased along a seaward gradient in the Spartina salt marsh and increased with vegetation biomass. Furthermore, the concentrations of trace elements and some metal elements in the sediment were higher under Spartina although these increases were not significant. Also, in the Spartina marsh, some heavy metals were concentrated in the surface layer of the sediment. The Spartina salt marsh in this study was only four years old; therefore, it is suggested that further study of this allen species on a longer time frame in the Jiangsu coastland should be carried out.

关键词： alien species biogeochemical processes intertidal ecosystem salt marsh Spartina alterniflora Loisel

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Solubility of the Ternary System Mg2.//Cl-,SO42.-H2. at 2.8.15 K and the Comparison of Model Simulation

Solubility of the Ternary System Mg2+//Cl-,SO42--H2O at 298....

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第十六届全国化学热力学和热分析学术会议

作者： H.Li~1,D.Zeng~(1,2.*),Y.Yao~1,X.Yin~2.D.Li~1 1 Qinghai institute of salt {2.,{3. Academy of sciences,xining,Qinghai 810008,P.R.china, 2.College of Chemistry and Chemical Engineering,Central South University,Changsha, Hunan 410083.P.R.china

The ternary system Mg Cl,SO -HO is a important subsystem concerning resource extraction from salt lake brine,which has been widely ***,the reported solubility data concerning this system are contradictory with each **... 详细信息

关键词： solubility MgCl2 MgSO4 Pitzer and PSC model

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Edaphic factors determining variation of two ecotypes of Leymus chinensis in North china

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Progress in Natural Science:Materials International 2006年第11期16卷 1150-1155页

作者： ZHOU Chan~1 and YANG Yunfei~2.*(1. MOE Key Laboratory of Environmental Change and Natural Disasters, College of Resources Science and Technology, Beijing Normal University, Beijing 100875, china 2. Key Laboratory of Vegetation Ecology, Ministry of Education, institute of Grassland Science, Northeast Normal University, Changchun 1{2.02., china) [a]MOE Key Laboratory of Environmental Change and Natural Disasters College of Resources Science and Technology Beijing Normal University Beijing China [b]Key Laboratory of Vegetation Ecology Ministry of Education Institute of Grassland Science Northeast Normal University Changchun China

To identify ecotypic variation of L. chinensis, the physiological characteristics and environmental factors were measured and assessed for grey-green and yellow-green ecotypes of L. chinensis grown in the salt-alkalized and aeolian sandy soils. Although both ecotypes presented a similar salt-alkaline tolerance under the experimental conditions, they differed in several aspects. The L. chinensis grown in the aeolian sandy soils had higher water potential and chlorophyll content and lower proline content in their leaves than those grown in the salt-alkalized habitat, and the grey-green ecotype of L. chinensis in both types of soils had higher water potential, chlorophyll and proline contents than the yellow-green ecotype. Besides, grey-green ecotypes had higher salt-alkaline tolerance than the yellow-green ecotype. The stepwise regression analysis showed that soil conductance and pH value were the main ecological factors affecting the physiology of L. chinensis. From the natural distribution of the two ecotypes, we considered that salt-alkaline in the soils is the leading factor in determining ecotypic variation of L. chinensis. The two ecotypes were first named grey-green and yellow-green ecotypes respectively.

关键词： L.chinensis ecotype adaptability variation ecological factor salt-alkaline in soil.

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PREPARATION OF Pb-Ca-Na MASTER ALLOY USING MOLTEN CHLORIDE salt ELECTROLYSIS

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中国有色金属学会会刊：英文版 1996年第2期6卷 18-19,21+25页

作者： Song Renying Wang Xingjie Luo Shumei Jiang Chan Tang Dingxiang(Changchun institute of Applied Chemistry ,chinese Academy of {2., Changchun 13.02.) chinese ACAD SCI CHANGCHUN INST APPL CHEMCHANGCHUN 130022PEOPLES R CHINA

ＰＲＥＰＡＲＡＴＩＯＮＯＦＰｂ－Ｃａ－ＮａＭＡＳＴＥＲＡＬＬＯＹＵＳＩＮＧＭＯＬＴＥＮＣＨＬＯＲＩＤＥＳＡＬＴＥＬＥＣＴＲＯＬＹＳＩＳＳｏｎｇＲｅｎｙｉｎｇ；ＷａｎｇＸｉｎｇｊｉｅ；ＬｕｏＳｈｕｍｅｉ；ＪｉａｎｇＣｈ... 详细信息

ＰＲＥＰＡＲＡＴＩＯＮＯＦＰｂ－Ｃａ－ＮａＭＡＳＴＥＲＡＬＬＯＹＵＳＩＮＧＭＯＬＴＥＮＣＨＬＯＲＩＤＥＳＡＬＴＥＬＥＣＴＲＯＬＹＳＩＳＳｏｎｇＲｅｎｙｉｎｇ；ＷａｎｇＸｉｎｇｊｉｅ；ＬｕｏＳｈｕｍｅｉ；ＪｉａｎｇＣｈａｎ；ＴａｎｇＤｉｎｇｘｉａｎｇ（...

关键词： Pb-Ca-Na master alloy molten chloride salt electrolysis preparation

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Phase Equilibria in the Aqueous Ternary System Containing Lithium,Magnesium,and Sulphate ions at 2.8.15 K

Phase Equilibria in the Aqueous Ternary System Containing Li...

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第十六届全国化学热力学和热分析学术会议

作者： Shi-Qiang Wang~1,Wei Qiao~1,Ya-Fei Guo~1 and Tian-Long Deng~(1,2. 1 Tianjin Key Laboratory of Marine Resources and Chemistry,College of Marine Science and Engineering, Tianjin University of Science and Technology Tianjin,3.0457,P.R.china, 2.ACS Key Laboratory of {2. Lake Resources and Chemistry,Qinghai institute of {2. lakes,chinese Academy of sciences,xining,810008,P.R.china,

＜正＞salt lakes of the Qaidam Basin consist of a series of lakes including Caerhan Lake,Dongtai Lake, Xitai Lake,and Yiliping Lake and are famous for their abundance of lithium,potassium,magnesium,and boron resources...

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Production of β-1,3.glucanase and chitinase of two biocon-trol agents and their possible modes of action

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chinese Science Bulletin 2002年第4期47卷 292-296页

作者： FAN Qing, TIAN Shiping, LIU Haibo & XU Yonginstitute of Botany, chinese Academy of {2., Beijing 100093.{3. institute of Botany Chinese Academy of Sciences Beijing China

Pichia membranefaciens Hansen and Candida guilliermondii (Cast) Langeronet Guerra are two antagonists of R. stolonifer on harvested nectarine and peach fruits. In this study, β-1,3.glucanase and chitinase activities of the antagonists were induced in vitro and in vivo. The highest β-1, 3.glucanase activity was detected in Lilly-Barnett minimal {2. medium supplemented with glucose in combination with CWP of R. stolonifer as a carbon source. The β-1,3.glucanase activity of P. membranefaciens reached the maximum level, being 114.0 SU (specific activity unit), and that of C. guilliermondii reached 103.2.SU. The lowest β-1,3.glucanase activity was observed in the medium containing glucose as sole car-bon source. P. membranefaciens was able to produce signifi-cantly higher levels of chitinase (exochitinase and endochiti-nase) in vitro than C. guilliermondii grown in Czapeck mini-mal medium. An increase in β-1,3.glucanase and chitinase activity was also triggered by wounding, adding of carbon sources

关键词： biological control yeast rhizopus rot β-1 3.glucanase chitinase.

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THE　RELATION　BETWEEN　MOLECULAR　MOTION　AND　ION　CONDUCTIVITY　ON　A　NEW　COMBLIKE　POLYMER

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chinese Chemical Letters 1996年第7期7卷 653-656页

作者： Li QI Yun Qing LIN Fo Song WANG(Changchun institute of Applied Chemistry, chinese Academy of {2.,Changchun 13.02.) chinese ACAD SCI CHANGCHUN INST APPL CHEMCHANGCHUN 130022PEOPLES R CHINA

A new amorphous comblike polymer(CBP) based on methylvinyl ether/maleic anhydride alternating copolymer backbone and on oligooxyethylene side chain was synthesized The dynamicmechanical properties of CBP-Li salt complexes showed that there were two glass *** are two peaks in the plot of the ionic conductivity *** salt concentration. The plot ofLog σagainst 1/(T-To) shows an unusual dual VTF behavior when using side chain glasstransition temperature (Tβ) as To.

关键词： RELATION THE MOLECULAR AND BETWEEN

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Coupling of water and land resources and its application in regionalization

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Journal of Environmental sciences 1999年第1期11卷 17-21页

作者： Chen Jian yao, Liu Chang ming institute of Geography, chinese Academy of {2., Beijing 100101,{3. E mail: chenjy@***

This paper focuses on the coupling of water and land resources based on several factors related closely to either water or land resources, which have become a topical subject due to the economic expansion and their sustainable development in recent years. A case of Qihe County in Shangdong Province, china has been used to demonstrate the methodology of the coupling and its application in regionalization with the help of geographical information system (GIS) tool. Field observation and measurement of soil salt and moisture in several profiles are used to verify the results of the coupling, which gives reasonable distribution of different areas regarding to the advantages and disadvantages for sustainable agriculture.

关键词： coupling water resource land resource regionalization.

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Structure and Properties of Aqueous NaB(OH)4Solution

Structure and Properties of Aqueous NaB(OH)4Solution

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第十六届全国化学热力学和热分析学术会议

作者： Y.Q.Zhou~(1,2.,C.H.Fang~(1,*),Y.Fang~1,F.Y.Zhou~(1,2.,H.W.Ge~1,Q.L.Chen~(1,2. 1 Qinghai institute of salt {2.,{3. Academy of sciences,xining 810008, 2.Graduate School of the {3. Academy of Science,Beijing 100049,

Sodium tetrahydroborate is the most attractive chemical hydride for H generation and storage in automotive fuel cell applications,but recycling from the by-product(NaB(OH)) is difficult and *** electrochemical regeneration process could represent an economically feasible and environmentally friendly *** micro-Structure and physicochemical properties such as the volumetric and the transport properties at moderate temperatures affect the H generation and storage system as well as the electrochemical recyclability of the ***,electrical conductivity,pH,viscosity and Raman spectra of aqueous NaB(OH) solutions were precisely *** distribution in aqueous NaB(OH) solutions at 2.8.15K and 3.3.15K was calculated using measured pH value and Hteratural equilibrium constant.

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