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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, 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 State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau Institute of Soil and Water Conservation Chinese Academy of Sciences Yangling China institute of Agro-Environment and Sustainable Development Chinese Academy of Agricultural Sciences Beijing China institute of geochemistry Chinese Academy of Sciences Guiyang 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 24.2% 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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Identification of marine natural gases with different origin sources

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Science china Earth sciences 2008年第S1期51卷 148-164页

作者： WANG YunPeng 1 ,ZHAO ChangYi 2 ,WANG ZhaoYun 2 ,WANG HongJun 2 ,TIAN Jin 1 ,ZOU YanRong 1 &LIU JinZhong1 1State Key Laboratory of Organic geochemistry,guangzhou institute of geochemistry,chinese academy of sciences.guangzhou 510640,china 2institute of Geology,Research institute of Petroleum Exploration and Development,Petrochina,Beijing 100083,china State Key Laboratory of Organic geochemistry Guangzhou Institute of Geochemistry Chinese Academy of Sciences Guangzhou China institute of Geology Research Institute of Petroleum Exploration and Development PetroChina Beijing China

Kinetic experiments of gas generation for typical samples of marine gas precursors including low-maturity kerogen,residual kerogen and oil as well as dispersed liquid hydrocarbon(DLH)in source rocks were performed by closed system,and the evolution trends of molecular and isotopic compositions of natural gases from different precursors against the maturity(R0%)at laboratory conditions were *** diagrams of gas origin were calibrated by using the experimental data.A diagram based on the ratio of normal and isomerous butane and pentane(i/nC4-i/nC5)was proposed and used to identify the origins of the typical marine natural gases in the Sichuan Basin and the Tarim Basin, *** the maturities of natural gases were estimated by using the statistical relationships between the gaseous molecular carbon isotopic data and maturities(δ13C-R 0 %)with different *** results indicate that the molecular and isotopic compositions of simulated gases from different precursors are different from each *** example,the dryness index of the oil-cracking gas is the lowest;the dryness indices of gases from DLH and kerogen in closed system are almost the same;and the dryness index of gases from residual kerogen is extremely high,indicating that the kerogen gases are very dry;the contents of non-hydrocarbon gases in kerogen-cracking gases are far higher than those in oil-cracking and DLH-cracking *** molecular carbon isotopes of oil-cracking gases are the lightest,those of kerogen in closed system and GLH-cracking gases are the second lightest,and those of cracking gases from residual kerogen are the *** calibration results indicate that the diagrams of ln(C1/C2)-ln(C2/C3)andδ13C2-δ13C3-ln(C2/C3)can discriminate primary and secondary cracking gases,but cannot be used to identify gas origin sources,while the diagram of i/nC4-i/nC5 can differentiate the gases from different *** application results of these diagrams show that gas mixtures ext

关键词： marine organic matter gas origin sources kerogen oil-cracking gas origin identification carbon isotope

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Proterozoic copper metaliogenic framework and geochemistry steep zone in central Yunnan Province

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chinese Science Bulletin 1999年第S2期44卷 163-164页

作者： CHANG Xiangyang, ZHU Bingquan and DONG Yunpeng guangzhou institute of geochemistry, chinese academy of sciences. guangzhou, 510640, china

THE wildly horizontal and vertical chemical heterogeneties, which result from the inchoate core-mantledifferentiation of the globe and the spatio-temporal difference of various regions in the globe, bring on themantle and crust from different landmass and oceans with markedly elemental and isotopic *** these signatures could be used to differentiate the attribute from various landmass or oceans andrecover the scent of kinematics and chemical geodynamics process. It is a quantificational method compared with the division by geotectonics facies and paleontologic fauna. Based on the geochemistry mapping of elements and multi-isotopic systematics of rocks derived frommantle and crust and combined with the studies on geophysical tomographic image, four type geochemicalprovinces can be distinguished. They are: (i) the Pacific (such as N-Pacific, N-Atlantic, the

关键词： Proterozoic copper metallogenesis geochemical steep zone Yunnan.

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Progress in experimental geochemistry

Progress in experimental Geochemistry

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中国矿物岩石地球化学学会第13届学术年会

作者： XIONG Xiao-lin guangzhou institute of geochemistry,chinese academy of sciences.guangzhou 510640,china

Tonalites-trondhjemites-granodiorites(TTG) account for more than 70%of the Archean continental *** is widely accepted that the TTG were produced by melting of metabasalts in the subducted oceanic crust. However,whether the melting occurs in shallow-level amphibolite facies or in relatively deep eclogite facies is *** are characterized by negative Nb-Ta-Ti ***(TiO) is a common residual accessory phase during the melting of metabasalts and is rich in Nb,Ta and ***,rutile stability is of key importance for understanding the genesis and formation conditions of TTG ***,experiments on phase relationships in the partial melting field of basalt and experiments on TiO solubility in the residual minerals and partial melts were conducted with a piston cylinder to constrain the ranges of pressure,temperature and

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Efficient transformation and expression of gfp gene in the edible mushroom Pleurotus nebrodensis

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Progress in Natural Science:Materials International 2008年第7期18卷 819-824页

作者： Junfang Lin a,b, Mingyao Zheng a, Jie Wang a,b, Wei Shu c, Liqiong Guo a,b,* a Department of Biotechnology, College of Food sciences. South china Agricultural University, guangzhou 510640, china b institute of Biomass Research, South china Agricultural University, guangzhou 510640, china c Test and Experimental Center, South china Agricultural University, guangzhou 510640, china Department of Biotechnology College of Food Sciences South China Agricultural University Guangzhou 510640 China institute of Biomass Research South China Agricultural University Guangzhou 510640 China Test and Experimental Center South China Agricultural University Guangzhou 510640 China

An efficient transformation method mediated by PEG-protoplasts was developed for the newly commercial edible mushroom Pleu- rotus nebrodensis. Two plasmids were used to co-transform protoplasts of P. nebrodensis. One plasmid is pAN7-1 containing a positive selectable marker gene hph conferring hygromycin B resistance. Another plasmid is pBlue-GFP containing a reporter gene gfp conferring green fluorescent protein. PCR and Southern blot analysis showed that hph gene or/and gfp gene were integrated into the genome of P. nebrodensis transformants. The transformation efficiency of the positive selectable marker gene hph was 3 transformants per microgram of plasmid pAN7-1 DNA, which was about 30 times higher than that previously reported in thoroughly studied Pleurotus species such as Pleurotus ostreatus. The transformation efficiency of the reporter gene gfp was 9 transformants per microgram of plasmid pBlu-GFP DNA. The co-transformation efficiency was 23.68%. This is the first report that a "reporter" gene, green fluorescent protein gene can be successfully stably expressed in this Pleurotus species.

关键词： Pleurotus nebrodensis Protoplast-mediated transformation Green fluorescent protein GFP expression

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THE EVOLUTIONARY HISTORY OF THE WEST KUNLUN MOUNTAINS: A TECTONIC RECONSTRUCTION BASED ON STUDIES OF MAGMATISM

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地学前缘 2000年第S1期7卷 262-263页

作者： Yuan Chao 1,2 , Sun Min 2, Li Jiliang 3[WT5,5”BX](1 guangzhou institute of geochemistry, chinese academy of sciences. guangzhou 510640,china 2.Department of Earth sciences. The University of Hong Kong, Pokfulam Road, Hong Kong, china 3.Institut

The Kunlun Mountains is situated in the north margin of the Tibetan plateau and is one of crucial areas for unraveling the tectonic evolutionary history of the plateau and Eurasia. However, there is no widely accepted model for this area. One of the reasons is that some basic issues for the tectonic reconstruction have not been well settled, they are: (1) Is the Kunlun Mountains an ancient accretion prism, or a mini continent with old basement?(2) What is the age of the Kudi ophiolite, early Paleozoic or late Paleozoic?(3) When did the South Kunlun Block accrete to the Tarim Block?(4) Do the fifth and the forth sutures represent different oceans, or they are just the chronologically different relics of the same ocean?(5) Did the Kunlun Mountains experience continuous subduction since Neoproterozoic?(6) When did the Paleo\|Tethys closed in the West Kunlun range?

关键词： West Kunlun Mountains Proto\|Tethys Paleo\|Tethys boninite series rocks accretion prism magmatic gap tectonic reconstruction

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Oxygen isotopic (^(17)O-^(18)O) heterogeneity in Archaean continental nucleus, North china Craton

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chinese Science Bulletin 1999年第24期44卷 2267-2269页

作者： LIU Jianzhong, ZHANG Fuqin, LI Chunlai and WANG Shijie institute of geochemistry , chinese academy of sciences., Guiyang 550002 , china institute of Geophysics , chinese academy of sciences., Beijing 100101 , china institute of geochemistry Chinese Academy of Sciences Guiyang China institute of Geophysics Chinese Academy of Sciences Beijing China

The oxygen isotopic data for amphibolites from Archaean continental nucleus, North china Craton indicate that ( i ) the evolving lines structured by the data are parallel to the geoselenic evolving line, which means that the parent materials of these continental nucleus o-riginated from solar matter; ( ii ) different intercepts for these evolving lines manifest that oxy-

关键词： North china Craton oxygen isotope (I7O-18O ) heterogeneity.

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Experimental measurement of the electrical conductivity of single crystal olivine at high temperature and high pressure under different oxygen fugacities

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Progress in Natural Science:Materials International 2006年第4期16卷 387-393页

作者： DAI Lidong, LI Heping, LIU Congqiang, CUI Tongdi, SHAN Shuangming, YANG Changjun, LIU Qingyou and DENG Heming Laboratory of the Earth’s Interior Materials and Fluid geochemistry, institute of geochemistry, chinese academy of sciences. Guiyang 550002, china Graduate School of the chinese academy of sciences. Beijing 100039, china institute of geochemistry, chinese academy of sciences. Guiyang 550002, china Guizhou University, Guiyang 550004, china Laboratory of the Earth's Interior Materials and Fluid geochemistry Institute of Geochemistry Chinese Academy of Sciences Guiyang 550002 China Graduate School of the chinese academy of sciences Beijing 100039 China institute of geochemistry chinese academy of sciences Guiyang 550002 China Guizhou University Guiyang 550004 China

At 1.0-4.0 GPa and 1123-1473 K and under oxygen fugacity-controlled conditions (Ni + NiO, Fe + Fe3O4, Fe + FeO and Mo+ M0O2 buffers), a YJ-3000t Model six-anvil solid high-pressure apparatus and a Sarltron-1260 Impedance/Gain-Phase analyzer were employed to conduct an in situ measurement of the electrical conductivity of single crystal olivine. Experimental results showed that: (1) within the range of experimentally selected frequencies (103-106 Hz), the electrical conductivity of the sample is of great dependence on the frequency; (2) with the rise of temperature ( T), the electrical conductivity (σ) will increase, and the Arrenhius linear relationship is established between lgσ and 1/T; (3) under the control of oxygen buffer Fe+ Fe3O4, with the rise of pressure, the electrical conductivity tends to decrease whereas the activation enthalpy and independent-of-temperature preexponential factor tend to increase, with the activation energy and activation volume of the sample estimated at (1. 25 ± 0.08) eV and (0.105 ±0.025) cm3/mol, respectively; (4) under given pressure and temperature conditions, the electrical conductivity tends to increase whereas the activation energy tends to decrease with increasing oxygen fugacity; and ( 5) the mechanism of electrical conduction of small polarons can provide insight into the behavior of electrical conduction of olivine under high pressure and high temperature.

关键词： olivine high temperature and high pressure electrical conductivity oxygen fugacity small polaron.

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Metallogenic mechanisms of super-large Cu and Au deposits in the Dexing region and simulating experiments

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chinese Journal Of geochemistry 2010年第1期29卷 1-14页

作者： WU Xueyi and WANG Zijiang The State Key Laboratory of Ore Deposit geochemistry,institute of geochemistry,chinese academy of sciences.Guiyang 55002,china The State Key Laboratory of Ore Deposit geochemistry Institute of Geochemistry Chinese Academy of Sciences Guiyang China

Based on the results of previous studies and under the direction of the theory of "ore deposit genesis",the authors made use of high temperature and high pressure experimental facilities and conditions at the Tectono-geochemistry Research Room under the State Key Laboratory of Ore Deposit geochemistry,institute of geochemistry,chinese academy of sciences.and put the focus on the multi-source of tectonically controlling ore-forming materials,the characteristics of multi-stage and multi-episode hydrothermal activities and mineralization and the characteristics of multi-genesis and multi-ore deposition so as to shed light on the metallogenic mechanisms of super-large Cu and Au *** addition simulating experiments were made on multi-stage and multi-episode tectonic activities and rock and ore deformation,multi-stage and multi-episode tectonic activities and mobilization and migration of ore-forming materials,and multi-stage and multi-episode tectonic activities and superimposition and enrichment of ore-forming *** experimental results showed that under the action of multi-stage and multi-episode tectonic stress the deformation and fragmentation of not only rocks and ores have been intensified,and but also the ore-forming materials originally disbursed in the rocks and ores have been mobilized and migrated and superimposed and *** experimental results also provided the scientific experimental data and grounds for deep-going research on the rules of metallogenesis and geneses of super-large ore deposits in the Dexing region,Jiangxi Province.

关键词：成矿机制模拟实验德兴地区金矿床超大型构造地球化学成矿物质来源国家重点实验室

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On designated-weight Boolean functions with highest algebraic immunity

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Science china Mathematics 2010年第11期53卷 2847-2854页

作者： LIU MeiCheng1,3, DU YuSong2, PEI DingYi2 & LIN DongDai1 1The State Key Laboratory of Information Security, institute of Software of chinese academy of sciences. Beijing 100190, china 2College of Mathematics and Information sciences. guangzhou University, guangzhou 510006, china 3Graduate University of chinese academy of sciences. Beijing 100049, china The State Key Laboratory of Information Security Institute of Software of Chinese Academy of Sciences Beijing China Graduate University of chinese academy of sciences Beijing China College of Mathematics and Information sciences Guangzhou University Guangzhou China

Algebraic immunity has been considered as one of cryptographically significant properties for Boolean functions. In this paper, we study ∑d-1 i=0 (ni)-weight Boolean functions with algebraic immunity achiev-ing the minimum of d and n - d + 1, which is highest for the functions. We present a simpler sufficient and necessary condition for these functions to achieve highest algebraic immunity. In addition, we prove that their algebraic degrees are not less than the maximum of d and n - d + 1, and for d = n1 +2 their nonlinearities equalthe minimum of ∑d-1 i=0 (ni) and ∑ d-1 i=0 (ni). Lastly, we identify two classes of such functions, one having algebraic degree of n or n-1.

关键词： cryptography Boolean function algebraic immunity algebraic degree nonlinearity

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