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Journal of Environmental sciences 2010年第2期22卷 283-289页

作者： Bin Wu,Tongbin Chen Center for Environmental Remediation,institute of Geographic sciences and Natural Resources research,Chinese academy of sciences,Beijing 100101,china. Center for Environmental Remediation Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China

Follow-up investigation on hair arsenic concentration was conducted in an arsenic heavily polluted area of southern china in 2002 and 2006. The results showed that the geometric mean of hair arsenic concentration decreased from 2.95 mg/kg in 2002 to 1.78 mg/kg in 2006, when the percentage of the population with levels over 1 mg/kg only decreased from 93.4% in 2002 to 80.5% in 2006. Over this four-year period, the population with high arsenic concentrations decreased significantly while there was no obvious change in hair arsenic concentration for people who had relatively low concentrations. In terms of age distribution, young and old people had higher hair arsenic concentrations than the middle-aged. All of these results showed that it is difficult to reverse the negative impact of arsenic pollution on human health. Arsenic pollution has a long-term continuous influence on the health of local residents.

关键词： arsenic human health soil contamination hair arsenic

Investigation of radionuclide～(63)Ni(Ⅱ) sequestration mechanisms on mordenite by batch and EXAFS spectroscopy study

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Science china Chemistry 2012年第4期55卷 632-642页

作者： YANG ShiTong,SHENG GuoDong,GUO ZhiQiang,TAN XiaoLi,XU JinZhang & WANG XiangKe Key Laboratory of Novel Thin Film Solar Cells,institute of Plasma Physics,Chinese academy of sciences,hefei 230031,china Key Laboratory of Novel Thin Film Solar Cells Institute of Plasma Physics Chinese Academy of Sciences Hefei China

The sorption behavior and microscopic sequestration mechanisms of radionuclide 63Ni（II） on mordenite as a function of aging time, ionic srength, initial 63Ni（II） concentrations, solid content and coexistent electrolyte ions were investigated by the combination of batch and EXAFS techniques. Macroscopic experiment results show that the sorption of 63Ni（II） is dependent on ionic strength at pH〈7, and independent of ionic strength at pH〉7. The sorption percentage of 63Ni（II） on mordenite increases with increasing solid content, while the sorption capacity decreases as solid content increases. The presence of different electrolyte ions can enhance or inhibit the sorption of Ni（II） on mordenite in various degrees. EXAFS analysis results of the sam- ples under three different ionic strengths suggest that the retained 63Ni（II） in these samples exists in an octahedral environment with six water ligands. In the initial period of rapid uptake, the sorption of 63Ni（II） is dominated by the formation of innersphere surface complexes. As aging time increases, 63Ni（II） sequestration behavior tends to be mainly controlled by the formation of Ni phyllosilicate coprecipitates and/or Ni（OH）2（s） precipitates. Results for the second shell fit of the sample prepared at an initial 63Ni（II） concentration of 100 mg/L indicate the possible formation of Ni polynuclear surface complexes. Both the macroscopic sorption data and the molecular level evidence of 63Ni（II） surface speciation at the mordenite/water interfaces should be factored into better predictions of the mobility and bioavailability of 63Ni（II） in environment mediums.

关键词： mordenite – 63Ni(II) – aging time – initial concentration – EXAFS analysis

Trend of urban system structure under the restriction of water and land resources in Xinjiang

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Chinese Science Bulletin 2006年第A1期51卷 179-188页

作者： ZHANG Xiaolei & LEIJun Xinjiang institute of Ecology and Geography, Chinese academy of sciences, Urumqi 830011, china institute of Geographical Science and Natural Resources research, Chinese academy of sciences, Beijing 100101, china Graduate School, Chinese academy of sciences, Beijing 100039, china Xinjiang institute of Ecology and Geography Chinese Academy of Sciences Urumqi China institute of Geographical Science and Natural Resources research Chinese Academy of Sciences Beijing China Graduate School Chinese Academy of Sciences Beijing China

根据在 Xinjiang 影响城市的开发和城市的系统结构的水和陆地资源上的研究，这篇论文分析利用地位和城市的水资源的缺乏。城市的水资源的消费和浪费在一个增加趋势，这被考虑。然而，在 Xinjiang 的大多数城市和镇在水资源的缺乏水资源... 详细信息

根据在 Xinjiang 影响城市的开发和城市的系统结构的水和陆地资源上的研究，这篇论文分析利用地位和城市的水资源的缺乏。城市的水资源的消费和浪费在一个增加趋势，这被考虑。然而，在 Xinjiang 的大多数城市和镇在水资源的缺乏水资源的废物是严肃的，特别在小镇上。megapolis 和中等城市的发展被有限陆地资源显然限制。尽管有扩展小城市和镇的相对大的空格，水和陆地资源的输出好处是低的。为了完成城市的系统的顺序的扩大，在 Xinjiang 组织，在都市化的快速的发展拿一个圆和三条带和节俭资源的策略的城市的空间发展模式被建议。

关键词：城镇体系结构水资源土地资源供水能力新疆

Development of a Nickel-base Cast Superalloy with High Strength and Superior Creep Properties

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Journal of Materials Science & Technology 2005年第3期21卷 347-352页

作者： Jieshan HOU, Jianting GUO, Lanzhang ZHOU and Zhijun LI institute of Metal research, Chinese academy of sciences, Shenyang 110016, china institute of Metal research Chinese Academy of Sciences Shenyang 110016 China

Derived from Russian alloy CHS88U, six experimental Ni-base alloys named as A to F in the Ni-Cr-Co-W-Ti-Al-Hf system are designed, evaluated and processed. One of these alloys, F, shows excellent high temperature tensile strength and ductility with superior creep rupture properties. As predicted by using modeling tools such as PHACOM and NEW PHACOMP, there is hardly the tendency for formation of topologically close-packed phase (TCP) phase in alloy F. Furthermore, through microstructural observation, it is also found that no TCP phase is formed in alloy F after long-time exposure at high temperature. So alloy F has well balance of phase stability and mechanical properties in view of application for gas turbines. It is proved that d-electron approach can be applied for design and development of nickel-base superalloys for gas turbine application.

关键词： Conventional Ni-base superalloy Tensile strength Creep life PHACOMP

A Novel Deflection Method for Measuring the Growth Stress of Thermally Growing Oxide Scales

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Journal of Materials Science & Technology 2003年第3期19卷 231-234页

作者： Yuhai QIAN MeishuanShenyang National Laboratory for Materials Science, institute of Metal research, Chinese academy of sciences, Shenyang 110016, china Lab. for Mat. Sci. Inst. of Metal Res. Chinese Acad. of Sci. Shenyang 110016 China

A kind of new deflection technique has been developed for measuring the growth stress of thermally growing oxide scales during high temperature oxidation of alloys. The average growth stresses in oxide scales such as Al2O3, NiO and Cr2O3 formed on the surface of the superalloys can be investigated by this technique. Unlike the comventional deflection method, the novel method does not need to apply a coating for preventing one main face of thin strip specimen from oxidizing and can be used under the condition of longer time and higher temperature.

关键词： Oxide film Growth stress Deflection method

Microstructures and Creep Behavior of a Directionally Solidified NiAl-Fe(Nb) Multiphase Intermetallic Alloy

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Journal of Materials Science & Technology 2003年第1期19卷 59-62页

作者： Yihui QI, Jianting GUO and Chuanyong GUIDepartment of Superalloys, institute of Metal research, Chinese academy of sciences, Shenyang 110016, china Dept. of Superalloys Inst. of Metal Res. Chinese Acad. of Sci. Shenyang 110016 China Dept. of Mat. Eng. Liaoning Inst. of Technol. Jinzhou 121001 China

The microstructure and creep behavior of a DS NiAI-Fe(Nb) multiphase intermetallic alloy have been investigated. This alloyexhibits dendritic structure, in which dendritic arm is β-(Ni,Fe)(Fe,Al) phase surrounded by interdendritic region of γ'/γ *** results of the creep test indicated that all of the creep curves have similar characteristic, which is a short primary creepstage and a dominant steady state creep stage, and the creep strain ranges from 18% to 52%. The apparent stress exponentand the apparent activation energy were analyzed and discussed. The mechanism of the creep deformation was also analyzedby the observation of TEM.

关键词： NiAl Multiphase intermetallic alloy Microstructure Creep

Loss of Posterior Silk Gland Transcription Specificity of Fibroin Light Chain Promoter due to Absence of 41 bp Sequence Containing Possible Inhibitor Binding Sites

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Acta Biochimica et Biophysica Sinica 2005年第12期37卷 819-825页

作者： Ting-Qing GUO~(1,2) Jian-Yang WANG~(1,2) Sheng-Peng WANG~(1,2.3) Xiu-Yang GUO~(1,2) Ke-Wei HUANG3~3 Jun-Ting HUANG~3 Chang-De LU~11 institute of Biochemistry and Cell Biology,Shanghai institutes for Biological sciences.Chinese academy of sciences.Shanghai 200031.china 2 Graduate School of the Chinese academy of sciences.Shanghai 200031.china 3 Serictdtu research institute.Chinese academy of agricultural sciences,Zhenjiang 212018.china institute of Biochemistry and Cell Biology Shanghai Institutes for Biological Sciences Chinese Academy of SciencesShanghai 200031 China Graduate School of the Chinese academy of sciencesShanghai 200031 China Sericultural research institute Chinese Academy of Agricultural SciencesZhenjiang 212018 China

The gene encoding fibroin light chain protein (FibL) is specifically expressed in the posteriorsilk gland of silkworm and repressed in other *** binding sites of several transcription factorsrevolved in the silk gland transcription specificity of fibl promoter have been recognized,including SGFB,PSGF and *** we report the leak expression of the enhanced green fluorescent protein (EGFP)reporter gene in tissues other than the posterior silk gland in vivo when under the control of a shortened fiblpromoter with deletion of the 5′terminal 41 bp sequence,which is located at -650 nt to -610 nt upstream *** transcription starting *** of silk gland specificity of the promoters was performed by observationof green fluorescence in tissues of silkworm larvae following inter-haemocoelic injection of recombinantAutographa californica multiple nuclear polyhedrosis virus carrying the EGFP reporter gene controlled bydifferent lengths of fibl *** results indicated that availability of the binding sites of several knownfactors,including SGFB,PSGF and BMFA,is not sufficient for intact silk gland transcription specificity offibl promoter,and there are possible inhibitor binding sites in the 41 bp sequence (-650 nt to -610 nt)upstream of the transcription starting site which may be required to repress the activity of fibl promoter inother tissues.

关键词： promoter specificity fibroin light chain silkworm Bombyx mori recombinant AcMNPV

Analysis of Developmental Proteome at Egg Stage of Drone Honeybees (A. m. ligustica)

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agricultural sciences in china 2010年第3期9卷 392-400页

作者： FANG Yu and LI Jian-ke institute of Apicultural research, Chinese academy of agricultural sciences/Key Laboratory of Pollinating Insect Biology, Beijing 100093, P.R.china institute of Apicultural research Chinese Academy of Agricultural Sciences/Key Laboratory of Pollinating Insect Biology Beijing 100093 P.R.China

An investigation on the proteome of drone egg development of native Italian bee （Apis mellifera ligustica Spinola,1806） was carried out in order to prove up the characteristics in protein expression and regulation at egg stage and open out the molecular mechanism of the development. The experiment was carried out by two-dimensional gel electrophoresis. The results showed that there were 200, 242 and 233 proteins in a wide rang of molecular weight （12.42-169.60 kDa） and in a relatively narrow scope of pI （4.50-9.00） detected on day 1, day 2 and day 3, respectively, during the developmental process of the drone egg. Meanwhile, 164 protein spots were resolved at all the images （i.e., the protein was consistently expressed） along with the egg development, among which 7 were significantly up-expressed （P 〈 0.05） and 4 were significantly down-expressed （P 〈 0.05） while 79 had no significant differences （P 〉 0.05）. In addition, the specific proteins expressing proteins on day 1, day 2 and day 3 were 11, 18 and 18, respectively. Besides, 17 proteins expressed both on day 1 and day 2 but silenced on day 3, and 43 proteins expressed both on day 2 and day 3 but silenced on day 1, while only 8 proteins expressed both on day 1 and day 3 but silenced on day 2. The results indicate that 2-d-old eggs are at the most active expressional stage in the development of drone egg. The protein expressing at all images suggests that it should be indispensable for drone egg development, but their expression pattern is different. The proteins expressing at a specific age of egg suggest that specific proteins are needed in different developmental stages to regulate. And there are more house-keeping proteins in the developmental process of the drone egg than that of worker egg, and it will provide more targets for gene improvement.

关键词： honeybees drone egg two-dimensional gel electrophoresis proteome

Temperature Fluctuation Synthesis/Simultaneous Densification and Microstructure Control of Titanium Silicon Carbide (Ti_3SiC_2) Ceramics

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Journal of Materials Science & Technology 2000年第5期16卷 461-465页

作者： Zhimei SUN and Yanchun ZHOU (Ceramic and Composite Department, institute of Metal research, Chinese academy of sciences, Shenyang 110015, china) Ceramic and Composite Department Institute of Metal Research Chinese Academy of Sciences Shenyang 110015 China

A novel temperature fluctuation synthesis/simultaneous densification process was developed for the preparation of Ti3SiC2 bulk ceramics. In this process. Si is used as an in-situ liquid forming phase and it is favorable for both the solid-liquid synthesis and the densification of Ti3SiC2 rainies. The present work demonstrated that the temperature fluctuation synthesis/simultaneous densification process is one of the most effective and simple methods for the preparation of Ti3SiC2 bulk materials providing relatively low synthesis temperature. short reaction time; and simultaneous synthesis and densification. This work also showed the capability to control the microstructure, e.g., the preferred orientation, of the bulk Ti3SiC2 materials simply by applying the hot pressing pressure at different Stages of the temperature fluctuation process. And textured Ti3SiC2 bulk materials with {002} faces of laminated Ti3SiC2 grains normal to the hot pressing axis were prepared.

关键词： Ceramics Temperature Fluctuation Synthesis/Simultaneous Densification and Microstructure Control of Titanium Silicon Carbide Ti3SiC2 SiC

Decrease trend of dust event frequency over the past 200 years recorded in the Malan ice core from the northern Tibetan Plateau

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Chinese Science Bulletin 2005年第24期50卷 2866-2871页

作者： WANG Ninglian Key Laboratory of Cryosphere and Environment, Cold and Arid Regions Environmental and Engineering research institute, Chinese academy of sciences, Lanzhou 73000, china institute of Tibetan Plateau research, Chinese academy of sciences, Beijing 100085, china Key Laboratory of Cryosphere and Environment Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences Lanzhou China institute of Tibetan Plateau research Chinese Academy of Sciences Beijing China

By analyses of the dust layers in the Malan ice core from the northern Tibetan Plateau, it was found that dirty ratio in this core might be a good proxy for dust event frequency. The variations in the dirty ratio displayed a de- crease trend over the past 200 years, which implies that dust events became less frequent during the study period. The decrease trend in the variations in dust event frequency might be caused mostly by the natural processes, including increasing precipitation and weakening westerly which might be related with global warming. Furthermore, significant negative correlation was found between the dirty ratio and δ 18O in the Malan ice core. This is highly important for studying the effect of atmospheric dust on climate change.

关键词：青藏高原马伦冰核气候变化扬尘事件发生频率