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Physical mechanisms of plant roots affecting weathering and leaching of loess soil

Science China Earth sciences 2006年第9期49卷 1002-1008页

作者： LI Yong1,2. ZHANG Qingwen1,2. WAN Guojiang3. HUANG Ronggui3. PIAO Hechun3. BAI Lingyu2.& LI Lu2.1. state key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau, {2. of Soil and Water Conservation, chinese academy of sciences, Yangling 712.00, China 2. {2. of Agro-Environment and Sustainable Development, chinese academy of Agricultural {13., Beijing 100081, China 3. {2. of Geochemistry, chinese academy of sciences, Guiyang 550002. China 1. state key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau Institute of Soil and Water Conservation Chinese Academy of Sciences Yangling 712100 China 2. institute of Agro-Environment and Sustainable Development Chinese Academy of Agricultural Sciences Beijing 100081 China 3. institute of Geochemistry Chinese Academy of Sciences Guiyang 550002 China

Plant roots have potential impacts on soil mineral weathering and *** objective is to understand the physical mechanisms of plant roots affecting weathering andleaching of loess soil. Root densities were measured through the method of a large-size dug profile,and transport fluxes of soil elements were determined using an undisturbed monolith soilinfiltration device on the hilly and gully regions of the chinese Loess Plateau. The results showthat the improvement effects of soil environment by plant roots are mainly controlled by the densityand weight of the fibrous roots with the diameters less than 1 mm. Plant roots have the strongereffects on soil physical properties than chemical properties. The principal components analysis(PCA) indicates that soil physical properties by plant roots account for 56.7% of variations in soilenvironment whereas soil chemical properties and pH contribute about {3..{3. of the soil *** roles of plant roots in controlling soil weathering and leaching increased in the followingorder: infiltration enhancement > increase of bio-active substance > stabilization of soilstructure. The effects of plant roots on soil mineral weathering and leaching can be quantifiedusing the multiple regression models with the high prediction accuracies developed in this study.

关键词： plant roots, soil weathering and leaching rates, soil environment field, principal components analysis (PCA), chinese Loess Plateau.

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Syntheses of Clusters Containing C2.2.M=Co,Mo）Cores and Crystal Structure of 〔dpp〕〔Mo2.p2.CO）4〕·CH2.l2

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chinese Journal of Structural Chemistry 1999年第4期18卷 35-40页

作者： CHEN XueNian ZHANG Jie YIN YuanQi (state key Laboratory for Oxo Synthesis and Selective Oxidation,{2. {3. of {3. physics, the chinese academy of sciences, lanzhou 73.000)ZSUN Jie (Shanghai {3. of Organic Chemistry, the chinese Acad state key Lab. Oxo Synthesis S. Lanzhou Inst. of Chemical Physics Chinese Academy of Sciences Lanzhou 730000 China Shanghai Inst. of Organic Chemistry Chinese Academy of Sciences Shanghai 200032 China

１ＩＮＴＲＯＤＵＣＴＩＯＮＴｈｅｅｘｔｅｎｓｉｖｅａｎｄｒａｐｉｄｄｅｖｅｌｏｐｍｅｎｔｏｆｔｈｅｃｈｅｍｉｓｔｒｙｏｆｄｉｎｕｃｌｅａｒｔｒａｎｓｉｔｉｏｎｍｅｔａｌｃｏｍｐｌｅｘｅｓｂｒｉｄｇｅｄｂｙｕｎｓａｔｕ... 详细信息

１ＩＮＴＲＯＤＵＣＴＩＯＮＴｈｅｅｘｔｅｎｓｉｖｅａｎｄｒａｐｉｄｄｅｖｅｌｏｐｍｅｎｔｏｆｔｈｅｃｈｅｍｉｓｔｒｙｏｆｄｉｎｕｃｌｅａｒｔｒａｎｓｉｔｉｏｎｍｅｔａｌｃｏｍｐｌｅｘｅｓｂｒｉｄｇｅｄｂｙｕｎｓａｔｕｒａｔｅｄｈｙｄｒｏｃａｒｂｏｎｓ...

关键词： cobalt molybdenum diyne compounds crystal structure cluster

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Reaction Chemistry of W-Mn/SiO2.Catalyst for the Oxidative Coupling of Methane

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Journal of Natural Gas Chemistry 2003年第1期12卷 1-9页

作者： Shuben Listate key Laboratory for Oxo Synthesis and Selective Oxidation,{2.,{3.,{3., China state key Laboratory for Oxo Synthesis and Selective Oxidation Lanzhou Institute of Chemical Physics Chinese Academy of Sciences Lanzhou 730000 China

Reaction chemistry of the OCM reaction on W-Mn/SiO_2.catalyst has beenreviewed in this account. Initial activity and selectivity, stability in a long-term reaction,reaction at elevated pressures and a modelling test in a stainless-steel fluidized-bed reactor showthat W-Mn/SiO_2.has promising performance for the development of an OCM process that directlyproduces ethylene from natural gas. A study on surface catalytic reaction kinetics and used catalyststructure characterization revealed a possible reason why C_2.and CO_x selectivity changed duringthe long-term reaction. Further improvement of the catalyst composition and preparation methodshould be a future direction of study on OCM reaction over W-Mn/SiO_2.catalyst.

关键词： W-Mn/SiO_2.catalyst oxidative coupling of methane elevated pressure methane

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Wet-chemical synthesis and characteristics of Au nanoshell

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Science China Chemistry 2005年第5期48卷 431-435页

作者： LIU Zhongxin1,2. SONG Hongwei1, YU Lixin1,2. YANG Linmei1,2.& PAN Guohui1,2.1. key Laboratory of Excited state {2., Changchun institute of Optics, Fine Mechanics and {2., chinese academy of sciences, Changchun 13.03., China 2. Graduate School of the chinese academy of sciences, Beijing 10003., China 1. key Laboratory of Excited state {2. Changchun Institute of Optics Fine Mechanics and Physics Chinese Academy of Sciences 130033 Changchun China 2. Graduate School of the chinese academy of sciences 100039 Beijing China

Gold nanoshells were prepared by an easy wet-chemical method, with Ag nanoparticles used as the templates. Transmission electron microscopy (TEM) indicated that the shells were sphere in shape, the size was homogenous, being about 2. nm, and no hard ag-glomerates were observed. The plasma resonance absorption of gold was tuned from visible to near-infrared (NIR) with the increased volume of HAuCl4. The temperature grads (?T) of the gold nanoshell hydrosol under the exposure of an 808-nm optical fiber laser with different power den-sities were measured. The highest ?T was 3.℃ (5 W/cm2. irradiation area was 2.cm2.. This kind of gold nanoshell hydrosol is a promising material to be used in biomedicine such as photo-thermal cancer therapy, and its special photothermal convert property will photothermally trigger drug release.

关键词： wet-chemical synthesis, Au, nanoshell, NIR absorption, photothermal conversion.

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Fabrication of Transparent Superhydrophilic TiO_2.Nanofilm without UV-irradiation

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稀有金属材料与工程 2012年第S1期41卷 263-267页

作者： Du Wen1,2.Ye Yinping1,Li Hongxuan1,Zhao Fei1,2.Ji Li1,Quan Weilong1,2.Chen Jianmin1,Zhou Huidi1 1 {3. key Laboratory of {2. lubrication,{3. institute of chemical physics,chinese academy of {13.,{3. {12.,China 2.Graduate University of chinese academy of Science,Beijing 100049,China chinese Acad Sci Lanzhou Inst Chem Phys State Key Lab Solid Lubricat Lanzhou 730000 Peoples R China chinese Acad Sci Grad Univ Beijing 100049 Peoples R China

A transparent phase-pure anatase TiO2.nanofilm was prepared through magnetron sputtering method,and a subsequent annealing treatment awarded it the superhydrophilic *** make clear the mechanism of the heat-induced superhydrophilicity,the chemical composition and surface morphology of the film were investigated in detail and compared before and after the annealing treatment mainly by field emission scanning electron microscopy(FESEM),X-ray diffraction method(XRD),Raman spectroscopy,and X-ray photoelectron spectroscope(XPS).The results suggest that the probable mechanism is in accordance with the UV-induced mechanism,where the heat-induced surface oxygen vacancies and hydroxyl radicals play important roles for achieving the superhydrophilicity.

关键词： superhydrophilicity transparent TiO2 nanofilms magnetron sputtering annealing treatment

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Enantioselective Hydrogenation of α,β-Unsaturated Cyclic Ketones by Double Asymmetric Induction Preparation of (R)-Muscone

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chinese chemical Letters 1997年第6期8卷 477-478页

作者： Bao Han XIE Shi Jie LU Hong Xiang FU Lan Yong GAO (state key Laboratory for Oxo Srnthesis and Selective Oxidation{2..{3.,{3.) chinese ACAD SCI LANZHOU INST CHEM PHYSSTATE KEY LAB OXO SYNTH & SELECT OXIDATLANZHOU 730000PEOPLES R CHINA

By ketal formation with chiral glycols like methyl or ethyl ester of tartaric acid,hydrogenation of ketals from the correspondingα,β-unsaturated 15-membered cyclic ketone produces (R)-muscone in good chemical and op... 详细信息

关键词： Unsaturated Cyclic Ketones by Double Asymmetric Induction Preparation of Muscone

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Deposition features of Ni on self-assembled microtubule template from biolipid by electroless method

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Science China Chemistry 2004年第3期47卷 228-234页

作者： FU Yubin1,2. ZHANG Lide1, ZHENG Jiyong2. FU Shangang3.& ZHU Mingwei3.1. institute of {3. {2. {3., chinese academy of sciences, Hefei 2.003., China 2. Luoyang Ship Material Research institute, Luoyang 47103., China 3. College of Life Science, Henan Normal University, Xinxiang 453.02. China 1. institute of solid {2. {3. Chinese Academy of Sciences 230031 Hefei China 2. Luoyang Ship Material Research institute 471039 Luoyang China 3. College of Life Science Henan Normal University 453002 Xinxiang China

Diacetylenic glycero-phosphatidylcholine is a chiral molecule with amphiphilic property, and it can self-assembly into a lipid microtubular structure. The lipid microtubule is a stable structure formed by tightly wound helical ribbons, and the ribbon-wrapping patterns have a significant effect on their chemical deposition on the microtubules. The deposition of colloidal Pd catalyst occurs mainly on the helical edge of the wound helical ribbons to form helical deposition lines of colloidal Pd particles in the interior and exterior of the lipid microtubules, resulting in an uneven chemical deposition of Ni on the microtubules. Catalyzed by as-deposited colloidal Pd, metallized Ni microtubules are characterized by a helical form, which may be in relation to inner stress due to the thickness difference or the different deposition processes. The observation of microtom shows that metallized tubules have a hollow structure. Some metallized tubules have a kind of coaxial double layer structure observed in the direct experiment evidence, indicating that metallization can occur in the inner and outer surface of the lipid tubules. Both lipid microtubules and metallized microtubules can be used as vehicles for encapsulating biological active molecules to control their release and to develop micro-components in biological and mechanical systems. {2.words molecular self-assembly - lipid microtubules - helical pattern - site-specific deposition - electroless metallization

关键词： molecular self-assembly, lipid microtubules, helical pattern, site-specific deposition, electroless metallization.

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Ice core dust particulate by XPS-SEM/EDAX——Impact of dust particulate on SO_4^(2.) record in ice cores

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chinese Science Bulletin 1999年第15期44卷 1424-1427页

作者： LI Zhongqin , LU Gongxuan , LIU Baozhong , FU Hongxiang LIU YuTianshan Glaciological Station , lanzhou institute of Glaciology and Geocryology ,{2. ,{3.,China state key Laboratory for Oxo Synthesis and Selective Oxidation, lanzhou institute of chemical physics , chinese academy ofsciences ,{3., China, Tianshan Glaciological Station Lanzhou Inst. Glaciol. Geocryology Chinese Academy of Sciences Lanzhou 730000 China state key Lab. Oxo Synthesis S. Lanzhou Inst. of Chemical Physics Chinese Academy of Sciences Lanzhou 730000 China

The ice core dust particulate sampled from Mt. Xixabangma has been analyzed by means of X-ray photoelectron spectrometer （XPS） and scanning electron microscope with energy dispersion X-ray analysis （SEM/EDAX）. The results show that the contents of SO42. and SO3./sub>2. in the surface layer of the dust are significantly higher than those in the subsurface layer （with the exception of organic sulfide）. This difference indicates that the surface SOx has been captured and then chemically converted by the atmospheric dust particulate before its deposition with snow, which is obviously different from those inner layer sulfates and sulfites contained by dust itself. In addition, it has been determined by SEM/EDAX that the dust contains relatively high concentrations of transition metal elements such as Fe and Ti oxides which could function as photocatalysts to the conversion of SOx adhered on the surface of the dust, and consequently accelerate the deposition of SOx to snow. Our research also

关键词： ice core records dust partculate sulfate ions.

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Hydrocarboxylation of Styrene in Water-Soluble Catalyst System Pd(OAc)2.TPPTSH-HOAc-H2.

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分子催化 1997年第2期 2-3页

作者： XIE Baohan KOU Yuan * YINGYuanqi (state key Laboratory for Oxo Synthesis and Selective Qxidation{2. The{3.{3.)

ＨｙｄｒｏｃａｒｂｏｘｙｌａｔｉｏｎｏｆＳｔｙｒｅｎｅｉｎＷａｔｅｒ┐ＳｏｌｕｂｌｅＣａｔａｌｙｓｔＳｙｓｔｅｍＰｄ（ＯＡｃ）２┐ＴＰＰＴＳＨ┐ＨＯＡｃ┐Ｈ２ＯＸＩＥＢａｏｈａｎＫＯＵＹｕａｎ＊ＹＩＮＧＹｕａｎｑｉ（... 详细信息

ＨｙｄｒｏｃａｒｂｏｘｙｌａｔｉｏｎｏｆＳｔｙｒｅｎｅｉｎＷａｔｅｒ┐ＳｏｌｕｂｌｅＣａｔａｌｙｓｔＳｙｓｔｅｍＰｄ（ＯＡｃ）２┐ＴＰＰＴＳＨ┐ＨＯＡｃ┐Ｈ２ＯＸＩＥＢａｏｈａｎＫＯＵＹｕａｎ＊ＹＩＮＧＹｕａｎｑｉ（ＳｔａｔｅＫｅｙＬａｂｏｒａｔｏｒ...

关键词： Hydrocarboxylation Styrene Water soluble catalyst Palladium acetate

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Dry electrode for the measurement of biopotential signals

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Science China(Information sciences) 2011年第11期54卷 2435-2442页

作者： WANG Yu 1,2.PEI WeiHua 2.GUO Kai 2.GUI Qiang 2.LI XiaoQian 2.CHEN HongDa 2.& YANG JianHong 11 institute of Microelectronics,School of Physical Science and Technology,lanzhou University{2.,China 2.{3. key Laboratory on Integrated Optoelectronics,institute of Semiconductors,{13. academy of sciences,Beijing 100083.China 1. institute of Microelectronics School of Physical Science and Technology Lanzhou University Lanzhou 730000 China2. State Key Laboratory on Integrated Optoelectronics Institute of Semiconductors Chinese Academy of Sciences Beijing 100083 China

This paper introduces a kind of silicon-based dry electrode for measuring biological *** uses microneedle arrays to penetrate into the stratum corneum to reduce skin *** dry electrode requires neither skin preparation nor the electrolytic gel,is easy to use and causes no skin *** different technologies are chosen to manufacture microneedle arrays of dry *** is deep dry etching combined with isotropic wet *** other is mechanical dicing combined with chemical wet etching (including isotropic wet etching and anisotropic wet etching).Microneedle arrays are coated with metal and divided into 2. mm 2.as dry electrode *** testing shows that the impedance value of dry electrode can be comparable with that of commercial electrode in the 2. Hz-10 kHz frequency *** steady-state visual evoked potential recording and analysis prove that the dry electrode can be used to detect electroencephalography.

关键词： dry electrode microneedle array dry etching wet etching EEG

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