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Variations of δ^(18)O in precipitation from the Muztagata Glacier, east Pamirs

Science china Earth sciences 2006年第1期49卷 36-42页

作者： LI Zhen1, YAO Tandong1,2. TIAN Lide1,2. XU Baiqing1,2.& Wu Guangjian2.1. key laboratory of Cryosphere and {2., Jointly Established by Cold and Arid Regions {2.al and Engi-neering research Institute and Institute of Tibetan Plateau research, chinese academy of sciences and chinese academy of Meteorological sciences, china Meteorological Administration, CAS, Lanzhou 730000, china 2. laboratory of {2. and Process on Tibetan Plateau, Institute of Tibetan Plateau research, chinese academy of sciences, Beijing 100085, china key laboratory of Cryosphere and {2. Jointly Established by Cold and Arid Regions Environmental and Engineering Research Institute and Institute of Tibetan Plateau Research Chinese Academy of Sciences and Chinese Academy of Meteorological Sciences China Meteorological Administration Lanzhou China laboratory of environment and Process on Tibetan Plateau Institute of Tibetan Plateau Research Chinese Academy of Sciences Beijing China

Expeditions to Muztagata (in the eastern Pamirs) during the summer seasons of2.02.and 2.03 collected precipitation samples and measured their oxygen isotopes. The δ^(18)O inprecipitation displays a wide range, varying from -17.40per thousand to +1.33per thousand inJune—September 2.02.and from -2..31per thousand to +4.59per thousand in May—August 2.03. Theδ^(18)O in precipitation correlates with the initial temperature of precipitation during theobserving periods. The positive correlation between δ^(18)O and temperature suggests that δ^(18)Ocan be used as an indicator of temperature in this region. The δ^(18)O values in fresh-snow samplescollected from two snow events at different elevations on the Muztagata Glacier show a strong''altitude effect'', with a ratio of nearly -0.40per thousand per 100 m from 5500 m to 7450 m.

关键词： Muztagata, δ18O, temperature, altitude effect.

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Natural interdecadal weakening of east asian summer monsoon in the late 2.th century

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Science Bulletin 2005年第17期 109-115页

作者： JIANG Dabang1, 2.& WANG Huijun1 1. Nansen-Zhu International research Center, Institute of Atmospheric Physics, chinese academy of sciences, Beijing 10002.,{2. 2. key laboratory of regional climate-environment research for tem-perate east asia, chinese academy of sciences, Beijing 10002.,{2.

Based on the reanalysis data throughout 1948―2.02.as derived from the United States National Centers for environmental Prediction and National Center for Atmos-pheric research, it is revealed that {2. asian summer mon-soon (EASM) intensity weakens on an interdecadal timescale since the mid-1960s, and twice interdecadal jumps are re-corded in the EASM intensity index series in the late 2.th century, respectively occurring in the mid-1960s and mid- to late 1970s. Six globally coupled atmosphere-ocean models’ outputs under the SRES A2.greenhouse gas and aerosol emission scenario, provided by the IPCC Data Distribution Center and the Hadley Center for climate Prediction and research, are then systematically examined. It follows that the above EASM weakening is not closely related to synchro-nizing anthropogenic global warming, and, therefore, it should be qualitatively natural change process. Over the 2.st century, the EASM intensity is likely increased slightly by continually intensified greenhouse effect relative to the late 2.th century.

关键词： east asian summer monsoon interdecadal weakening global warming natural change.

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Study on the coating of nano-scale SiO_2.film on the surface of nanocrystalline Mg-Al layered double hydroxides

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Science china Chemistry 2005年第2期48卷 107-114页

作者： ZHANG Zejiang1,2.3, MEI Xiujuan2. XU Chenghua1 & QIU Fali1 1. Chengdu Institute of Organic Chemistry, chinese academy of sciences, Chengdu 610041, china 2. Sichuan Fire {2. Institute of Public Security Ministry, Chengdu 611830, china 3. Graduate School of the chinese academy of sciences, Beijing 100039, china Correspondence should be addressed to Zhang Zejiang (email: zzjzzjzz@***) Chengdu Institute of Organic Chemistry Chinese Academy of Sciences Chengdu China Sichuan Fire research Institute of Public Security Ministry Chengdu China Graduate School of the chinese academy of sciences Beijing China

The coating process of a nano-scale SiO2.film on the nanocrystalline Mg-Al layered double hydroxides via a sol-gel process was investigated. The uniform and dense SiO2.ilm with a thickness of about 5 nm on the nano-LDHs particles was characterized by the solubility test in the dilute HNO3 or HCl acid, tem and FT-IR, XRD, TG and DSC. The chemical shifts of binding en- ergies of Al 2., Mg 2., Si 2. and O 1s on the coated particles indicate that the coating of the SiO2.nano-film on the surface of the nano-LDHs proceeds through the formation of Mg-O-Si and Al-O-Si bonds. The thermal analysis shows that both the SiO2.coated nano-LDHs and the nano-LDHs have a similar mass loss process, in which there are three obvious stages of mass loss in the temperature range of 40—700℃. Furthermore, the more the coatedamount of SiO2.n the surface of the nano-LDHs is, the less the mass loss of the samples is at 700℃.The nano- LDHs have two obvious endothermic peaks at 2.4.67℃ and 430.13℃, whose corresponding heat absorption capacities are 412.2. J/g and 336.30 J/g, respectively. In contrast, the coated nano-LDHs have only one endothermic peak at 2.3.60℃ with a heat absorption capacity of 2.1.2. J/g.

关键词： layered double hydroxides, nanocrystalline, silica, coating.

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Role of gallium wetting layer in high-quality ZnO growth on sapphire (0001) substrates

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Science china(Physics,Mechanics & Astronomy) 2004年第5期47卷 612-620页

作者： ZENG Zhaoquan1,3, WANG Yong2. DU Xiaolong1, MEI Zengxia1, KONG Xianghe3, JIA Jinfeng1, XUE Qikun1 & ZHANG Ze2. 4 1. State key laboratory for Surface Physics, Institute of Physics,{2., Beijing 100080,{2. 2. laboratory of Electron Microscopy, Institute of Physics,{2., Beijing 100080,{2. 3. College of Physics and Engineering, Qufu Normal University, Qufu 2.3165,{2. 4. Beijing University of Technology, Beijing 10002.,{2. State key laboratory for Surface Physics Institute of Physics Chinese Academy of Sciences Beijing China College of Physics and Engineering Qufu Normal University Qufu China laboratory of Electron Microscopy Institute of Physics Chinese Academy of Sciences Beijing China Beijing University of Technology Beijing China

A Ga wetting layer was used to modify the surface structure of sapphire (0001) substrate to prepare high-quality ZnO film by radio frequency plasma-assisted molecule beam epitaxy. We found that this Ga layer plays a crucial role in eliminating 30 rotation domains, controlling polarity and decreasing defect density in ZnO epilayers, as demonstrated by in situ reflection high energy electron diffraction, ex situ high resolution X-ray diffraction and high resolution cross-sectional transmission electron microscopy. Zn-polar film of ZnO was determined by convergent beam electron diffraction. A Ga bilayer model is proposed to understand the effects of the Ga wetting layer on high-quality ZnO growth.

关键词： Ga wetting layer, sapphire, polarity, defect density, zinc oxide, rf-MBE, RHEED, HRXRD, tem, CBED.

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Fabrication of multi-level branched metal nanowires by AAO template electro-deposition

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chinese Science Bulletin 2006年第17期51卷 2055-2058页

作者： XU Liping1,2. YUAN Zhihao1,2.& ZHANG Xiaoguang1,2.. Nanomaterials and Nanotechnology research Center, Tianjin Univer- sity of Technology, Tianjin 300191, china 2. Tianjin {2. {2. for Photoelectric Materials and Devices, Tian- jin 300191, china Nanomaterials and Nanotechnology research Center Tianjin University of Technology Tianjin China Tianjin key laboratory for Photoelectric Materials and Devices Tianjin China

Anodic aluminum oxide (AAO) tem- plates with various branched pores were prepared through one- to multi-step varying the anodic voltage by a factor of 1/ 2.during an anodization of alumi- num. The corresponding branched Fe nanowires (i.e. Y-branched, two-level branched and more complex tree-like nanostructures) were achieved by electrodepositing Fe into the branched pores of the AAO template. Selecting area electron diffraction and high-resolution tem images show that the stem and branches of the branched Fe nanowires are single- crystalline with a face-centered cubic lattice. These branched Fe nanowires will be of great fundamental and practical significance.

关键词：阳极氧化铝 AAO 金属纳米线电化学沉积

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Assembly of gold nanoparticles with H_(10)TTPR (3a, 4, 5, 8, 9, 9a, 10, 11-octa-hydro-2.,3H-1,6,7,12.tetrathia-perylene) as the rigid cross-linker

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chinese Science Bulletin 2004年第8期49卷 789-792页

作者： SHAO Xiangfeng1,2. WANG Tongxin1, ZHANG Deqing1, XU Wei 1 & ZHU Daoben1 1. Organic Solids laboratory, Center for Molecular sciences, Institute of Chemistry,{2., Beijing 100080, china 2. Graduate School,{2., Beijing 100080, china Correspondence should be addressed to Zhu Daoben or Zhang Deqing (e-mail: dqzhang@***) Organic Solids laboratory Institute of Chemistry Chinese Academy of Sciences Beijing 100080 China Graduate School Chinese Academy of Sciences Beijing 100080 China

Gold nanoparticles were assembled with the rigid cross-linker, H10TTPR. The assembly process was stud-ied with the UV-vis spectroscopy and tem. By adjusting the amount of H10TTPR added to the gold nanoparticle solutio... 详细信息

关键词：纳米金粒子集成刚性交叉连接 tem UV-力光谱学

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Episodic fluid movements in superimposed basin:Combined evidence from outcrop and fluid inclusions of the Majiang ancient oil reservoir,Guizhou Province

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Science china Earth sciences 2008年第S2期51卷 78-87页

作者： XIANG CaiFu1,2.TANG LiangJie1,2.LI RuFeng1,2.& PANG XiongQi1,2.1 Basin and Reservoir research Center,china University of Petroleum,Beijing 102.49,china 2.State key laboratory of Petroleum Resource and Prospecting,china University of Petroleum,Beijing 102.49,china Basin and Reservoir research Center China University of Petroleum Beijing China State key laboratory of Petroleum Resource and Prospecting China University of Petroleum Beijing China

Combined evidence from the outcrop and the fluid inclusion assemblage (FIA) analysis indicates that there exist two episodes of fluid flow controlled by the tectonic activity. The first episode was recorded mainly in the reservoir rock of the Honghuayuan Formation,representing the fluid flow of hydrocarbon charging. The second episode occurred mainly along the fault systems,representing the fluid move-ment when the ancient oil reservoir was destroyed. The host mineral morphology,homogeneous tem-perature,and salinity of the FIAs record an episodic fluid movement. Characters of high homogenous temperature,low salinity and a quick temperature variation of the first episode fluid flow may indicate an early-stage fluid eruption,and correspondingly,fine-grained calcite was formed. temperature of the erupted fluid tended to decrease during its mixing with the upper formation fluid and finally had the same temperature as the upper formation. From then on,the temperature was rather steady and fa-vored the growth of the coarse calcite. Due to this character of the temperature variation of the episodic fluid flow,we can use the homogenous temperature of the FIA of the coarse calcite to date the forma-tion and the destruction time of the Majiang ancient oil reservoir. Episodic fluid flow was known for its inhomogeneous trapping,which resulted in the failure of dating according to the burial history. But taking a close look at its temperature variation,we think that the latest stage of fluid flow,characterized by steady state temperature and grow of the coarser crystals,can be used for dating. It will be of great value if this method is proved to be effective. The formation and the destruction time of the Majiang ancient oil reservoir were dated to be in the Indosinian Period and the late Yanshan-early Hymalayan Period respectively. This conclusion is in great discrepancy with the common accepted idea that the Majiang ancient oil reservoir was formed and destroyed during the Cal

关键词： Majiang ancient oil reservoir episodic fluid flow marine carbonate rocks superimposed basin

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Crystallization Behaviour of Laser Synthesized Nanometric Amorphous Si_3N_4 Powders

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Journal of Materials Science & Technology 1995年第3期11卷 187-191页

作者： Yali LI Yong LIANG Zhuangqi HU(National key Lab. of Rapidly Solidified Nonequilibrium Alloys, Institute of Metal research,{2. {2. of sciences, Shenyang, 110015, china) Inst of Metal research Chinese Acad of Sciences Shenyang China

The crystallization behaviour of the laser synthesized nanometric amorphous Si3N4 powders with the particle size of 15 nm in diameter has been studied between 12.0° and 1700℃ by XRD,tem and FTIR techniques. A small amount of β-Si3N4 formed at 12.0℃ and increased slowly until the α- β transformation happened at 1700℃, whereas α-Si3N4 appeared at 1300℃ andincreased rapidly between 1500-1600℃. The formation of β phase at the lower temperature was caused by the nitridation of free Si due to the preexisted β-nuclei in the Si3N4 particles, wher{2.he α phase was formed by solid crystallization from the amorphous matrix. There were α and β SiC formed at 1700℃ due to the presence of Sio and Co gases in the system. FTIR analysis shows that two new IR absorption at 1356 and 142. cm-1, and an overall strong absorption in wide wavenumber range resulted from the powders annealed at 1600 and 1700℃ respectively

关键词： Si Am Crystallization Behaviour of Laser Synthesized Nanometric Amorphous Si3N4 Powders OO

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Effect of Pd on GFA and Thermal Stability of Zr-based Bulk Amorphous Alloy

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Journal of Materials Science & Technology 2004年第2期20卷 160-163页

作者： Fengxiang QIN, Haifeng ZHANG, Aimin WANG, Bingzhe DING and Zhuangqi HUShenyang National laboratory for Materials Science, Institute of Metal research,{2., Shenyang 110016, china Lab. for Mat. Sci. Inst. of Metal Res. Chinese Acad. of Sci. Shenyang 110016 China

The effect of Pd addition on the glass-forming ability and thermal stability of the Zr55Al10Cu30Ni5-xPdx (x=0, 1, 3, 5 at. pct) alloys upon copper-mold casting has been investigated. The structure, thermal stability and microstructure were studied by X-ray diffraction (XRD), differential scanning calorimetry (DSC) and transmission electron microscopy (tem), respectively. It was identified that a new bulk amorphous alloy with the larger supercooled liquid region Tx of 100 K is obtained with substituting Ni by 1 at. pct Pd. Furthermore, the origins that thermal stability and GFA change with increasing of Pd have also beer discussed.

关键词： Bulk Amorphous Alloy Glass-forming Ability Thermal stability

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Development of a chinese land data assimilation system:its progress and prospects

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Progress in Natural Science:Materials International 2007年第8期17卷 881-892页

作者： Li Xin~(1**) Huang Chunlin~1 Che Tao~1 Jin Rui~1 Wang Shugong~l Wang Jiemin~1 Gao Feng~1 Zhang Shuwen~2.Qiu Chongjian~2.Wang Chenghai~2.(1.Cold and Arid Regions environmental and Engineering research Institute,{2. academy of sciences,Lanzhou 730000,china 2.College of Atmospheric sciences,Lanzhou University,Lanzhou 730000,china) Cold and Arid Regions environmental and Engineering research Institute Chinese Academy of Sciences Lanzhou 730000 China College of Atmospheric sciences Lanzhou University Lanzhou 730000 China

The objective of land data assimilation is to merge multi-source observations into the dynamics of land surface model for improving the estimation of land surface *** have developed a land data assimilation system for china's land *** this sys- tem,the Common Land Model and Simple Biosphere Model 2.are used to simulate land surface *** radiative transfer models of thawed and frozen soil,snow,lake,and vegetation are used as observation operators to transfer model predictions into estimated bright- ness temperatures.A Monte-Carlo based sequential filter,the ensemble Kalman filter,is implemented as data assimilation method to inte- grate modeling and *** system is capable of assimilating passive microwave remotely sensed data such as special sensor mi- crowave/imager (SSM/I),TRMM microwave imager (TMI),and advanced microwave scanning radiometer enhanced for EOS (AMSR- E) and the conventional in situ measurements of soil and snow.A spatiotemporally consistent assimilated dataset for soil moisture,soil temperature,snow and frozen soil,with a spatial resolution of 0.2. degree and temporal resolution of one hour,has been *** paper introduces the development of chinese land data assimilation system and the progress made on data assimilation algorithms,land sur- face modeling,microwave remote sensing of land surface hydrological variables,and the preparation of atmospheric forcing *** dis- tinct characteristics and challenges of developing land data assimilation system and the perspectives for future development are also dis- cussed.

关键词： land data assimilation land surface model passive microwave remote sensing Kalman filter

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