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AFM study on the adsorption and aggregation behavior of dissolved humic substances on mica

Science china Chemistry 2006年第3期49卷 256-266页

作者： GE Xiaopeng1, ZHOU Yanmei2. Lü Chunhua1 & TANG Hongxiao1 1. State Key Laboratory of Environmental Aquatic Chemistry, Research Center for Eco-Environmental sciences, Chinese Academy of sciences, {2. 100085, china 2. school of Civil Engineering & Architecture, {2. Jiaotong university, {2. 100044, china 1. State Key Laboratory of Environmental Aquatic Chemistry Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China 2. school of Civil Engineering & Architecture Beijing Jiaotong University Beijing 100044 China

Humic substances constitute the major organic fractions of soils, sediments and natural waters, and play a dominant role in the binding, mobilization, transport and ultimate fate of organic contaminants in subsurface systems. In this paper, two humic acid samples, Guanting and Tianjin, with different origin and chemical compositions have been investigated with AFM imaging for their adsorption and aggregation behaviors on mica. While the Tianjin humic sample is found to form small spheres with 2.0 to 330 nm in diameter at lower concentrations, irregular loop-chain assemblies of hundreds of nanometer in diameter with the chain width of about 40 nm are dominant for the Guanting humic sample, which may attribute to the more polar aliphatic fractions in the chemical composition in the latter. The heterogeneous and polydisperse nature of humic substances with multiple structural features, such as sponge-like structures, perforated sheets, aggregate of spheres, branches and chain-like assemblies etc., is apparent at higher concentrations for both humic samples, showing morphologically new evidence for the dominant view of the humic dual-mode sorption model. With naphthalene introduced, the assemblies of Guanting humic substances clearly become more compact with significantly narrowed branches and less porous the perforated sheet-like structures. It is indica- tive of that smaller nanometer scale rings present along the perforated assemblies could potentially represent hydrophobic domains, which may facilitate the adsorption and aggregation of naphthalene onto the natural particle surfaces and therefore lead to an important role of dissolved humic sub- stances in the sorption of environmental pollutants.

关键词： atomic force microscopy (AFM) dissolved humic substances morphology aggregation adsorption

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Study on the Removal of Iron,Manganese and Nitrate in Groundwater by Biological Ribbon Technology

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地学前缘 2009年第S1期16卷 190-191页

作者： Yuchen Li,Yukun Ju school of Water resources & Environment,{2. university of geosciences(beijing),beijing 1.0083,{2.

The pollution of iron,manganese and nitrate in groundwater is a huge threat to human *** this study,column experiments of ceramic,manganese sand,ceramic sand,volcanic rock,quartz sand were *** and manganese contents of influent were 3.3 mg/L and 2.1 mg/*** the biofilm became mature,the highest iron and manganese removal rate achieved by manganese sand as a filter *** did a little worse than manganese sand,but other three filter material could not reach

关键词： removal of iron manganese and nitrate groundwater biological ribbon technology

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β2.Adrenergic receptor on T lymphocytes and its clinical implications

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Progress in Natural Science:Materials International 2009年第1期19卷 17-23页

作者： Xuelai Fan a,Yuedan Wang b,a Peking university,school of Pharmaceutical {2.,beijing 1.0083,china b Peking university,school of Basic Medical {2.,beijing 1.0083,china [a]Peking university School of Pharmaceutical Sciences Beijing 100083 China [b]Peking University School of Basic Medical Sciences Beijing 100083 China

Sustained complex cross-talk between the immune system and the nervous system plays a vital role in retaining homeostasis in a healthy *** of the central regulatory mechanisms involved is the existence and functions of β2.adrenergic receptors(β2.R) on T *** article reviews research progress made recently,including the expression of adrenergic receptors on T lymphocytes,the structure and intracellular pathways of β2.R,the activation of β2.R by either endogenous or exogenous agonists,and the effect of β2.R stimulation on T cells which alters T cell proliferation,differentiation,cytokine production and T-helper-mediated antibody ***,we discuss the roles of β2.R played in the pathogenesis and treatment of autoimmune diseases.

关键词： Neuroimmunology β2.adrenergic receptor T cell Autoimmune

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Experimental study of ore gabbro liquid immiscibility

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Science china earth {2. 2005年第4期48卷 496-505页

作者： SANG Zunan1,2. XIA Bin1, ZHOU Yongsheng3 & JIN Zhenmin4 1. Guangzhou Institute of Geochemistry, Chinese Academy of sciences, Guangzhou 510640, china 2. Wuhan {2., Wuhan 430072. china 3. Institute of Geology, china Seismological Bureau, beijing 10002., china 4. Faculty of earth sciences, china university of geosciences, Wuhan 430074, china 1. Guangzhou Institute of Geochemistry Chinese Academy of Sciences 510640 Guangzhou China 2. Wuhan university 430072 Wuhan China 3. Institute of Geology China Seismological Bureau 100029 Beijing China 4. Faculty of earth sciences China University of Geosciences 430074 Wuhan China

In this paper, the authors present the results of a preliminary experimental study on partial melting of fine-grained gabbro, Panzhihua, Sichuan Province, china. Experiments were conducted under (confining) pressure ranging from 450 to 500 MPa and temperature of 900— 12.0℃. The results show that the initial melt is distributed along grain boundaries and triple junctions. Liquid immiscibility phenomena are noted in the melt with two compositional different melt phases, i.e. matrix and sphere phases. The matrix phase is relatively rich in Si, Al and K, and is depleted in Mg, Fe, Ca, Na and Ti, whereas the sphere phase shows opposite trends. The calculation of the melt free energy indicates that the liquid immiscibility is governed by the rule of thermodynamics, as the liquid immiscibility would result in the decrease in free energy of the melt system. The field relationships suggest that the liquid immiscibility may have played an important role in the generation of ore magma of Panzhihua V-Ti magnetite ore deposit. This study thus provides experimental constraints on the mechanism of the formation of V-Ti magnetite deposite.

关键词： partial melting, experimental study, gabbro, liquid immiscibility, ore formation mechanism.

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Development of environmental monitoring satellite systems in china

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Science china earth {2. 2010年第S1期53卷 1-7页

作者： LI GuoPing1 & CAO ChunXiang2.1 school of earth and Space {2.,Peking university,beijing 100871,china 2.State Key Laboratory of Remote Sensing Science,Jointly Sponsored by the Institute of Remote Sensing Applications of Chinese Academy of {2. and beijing Normal university,beijing 100101,china 1. school of earth and Space {2. Peking University Beijing 100871 China2. State Key Laboratory of Remote Sensing Science Jointly Sponsored by the Institute of Remote Sensing Applications of Chinese Academy of Sciences and Beijing Normal University Beijing 100101 China

With the increase in global environmental problems,the necessity and urgency of remote sensing technology being applied to environmental monitoring has been widely recognized around the *** has launched the environment and disaster monitoring and forecasting small satellite constellation HJ-1A/B and the FY3 atmosphere and environmental satellite,but they still cannot fully satisfy requirements for environmental *** paper summarizes the current status of satellite environmental monitoring in china and the existing problems of inadequate load design and low data utilization efficiency,and discusses the demand for environmental monitoring *** on the development of foreign satellite systems for environmental monitoring,the future development and key tasks of the environmental monitoring satellite system in china is discussed,as are some related initiatives.

关键词： environmental satellite environmental monitoring global climate change specialty load satellite system

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L^2.Algebraic Decay Rate for Transient Birth-Death Processes

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Chinese Annals of Mathematics,Series B 2012年第4期33卷 583-594页

作者： Lijuan CHENG1 Yingzhe WANG2.1Laboratory of Mathematics and Complex Systems, the Ministry of Education of china school of Mathe-matical {2., beijing Normal university, beijing 100875, china. 2.aboratory of Mathematics and Complex Systems, the Ministry of Education of china school of Mathematical {2., beijing Normal university, beijing 100875, china. Laboratory of Mathematics and Complex Systems the Ministry of Education of China school of Mathematical sciences Beijing Normal University Beijing China

This paper is a continuation of the study of the algebraic speed for Markov processes. The authors concentrate on algebraic decay rate for the transient birth-death processes. According to the classification of the boundaries, a series of the sufficient conditions for algebraic decay is presented. To illustrate the power of the results, some examples are included.

关键词： Transient Birth-death processes Algebraic decay

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ON THE CENTRAL RELAXING SCHEME Ⅱ: SYSTEMS OF HYPERBOLIC CONSERVATION LAWS

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Journal of Computational Mathematics 2001年第6期19卷 571-582页

作者： Hua-zhong Tang (school of Mathematical sciences, Peking {2., beijing 100871, china) (LSEC,ICMSEC Academy of Mathematics and Systems sciences, Chinese Academy of sciences, beijing 100080, china) school of Mathematical sciences Peking University Beijing 100871 China

This paper continues to study the central relaxing schemes for system of hyperbolic conservation laws, based on the local relaxation approximation. Two classes of relaxing systems with stiff source term are introduced to approximate system of conservation laws in curvilinear coordinates. Based on them, the semi-implicit relaxing schemes are con- structed as in [6, 12. without using any linear or nonlinear Riemann solvers. Numerical experiments for one-dimensional and two-dimensional problems are presented to demon- strate the performance and resolution of the current schemes.

关键词： Hyperbolic conservation laws The relaxing system The central relaxing schemes The Euler equations.

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Laser probe ^(40)Ar/^(39)Ar dating of mica on the deformed rocks from Altyn Fault and its tectonic implications,western china

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Chinese Science Bulletin 2001年第4期46卷 322-325页

作者： LIU Yongjiang, YE Huiwen, GE Xiaohong, CHEN Wen, LIU Junlai, REN Shoumai & PAN HongxunCollege of earth sciences, Changchun {2. of Science and Technology, Changchun 130061, china Graduate school, china university of geosciences, beijing 1.0083, china Laboratory of Isotopic Geochronology, Institute of Geology, Ministry of Land and resources of china, beijing 100037, china College of earth sciences Changchun University of Science and Technology Changchun China Graduate school China University of Geosciences Beijing China Laboratory of Isotopic Geochronology Institute of Geology Ministry of Land and Resources of China Beijing China

The samples of Caledonian mylonitized granite and Jurassic meta-sedimentary rocks were collected in the north of Dangjinshan Pass, Qaidam gate fault-valley and Gesi fault-valley. Detailed studies under the microscope and electronic microscope suggest that all the samples contain the syntectonic-growing minerals such as white mica, chlorite, sericite, biotite, etc. By dating these minerals, we got a group of 40Ar/39Ar laser probe isochronal ages of 89-92.Ma and apparent ages of (46.6±6.4) Ma. The ages ranging from 97 to 46 Ma were reported for the first time in the isotopic dating researches of the Altyn Fault The isochronal age group of (98-89) Ma indicates that a ductile strike-slip event, with low-grade metamorphism, began in late Cretaceous. This suggests that the strike-slip movement of the Altyn Fault should be related to the formation of the so-called west tectonic syntaxis in the Nepal-western Kunlun area.

关键词： Altyn Fault 40Ar/39Ar age strike-slip movement.

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Research on the method for retrieving soil moisture using thermal inertia model

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Science china earth {2. 2006年第5期49卷 539-545页

作者： LIU Zhenhua1 & ZHAO Yingshi2.1. Information College, South china Agricultural university, Guangzhou 510642. china 2. Graduate university of Chinese Academy of sciences, beijing 100049, china 1. Information College South China Agricultural University Guangzhou 510642 China 2. Graduate university of Chinese Academy of sciences Beijing 100049 China

In order to improve accuracy of soil moisture inversion using remote sensing, a new thermal inertia model is proposed in this paper. The improved model needs only surface maximum temperature as the temperature parameter input instead of input of the surface temperature difference, as well as the surface sensible and latent fluxes are introduced into boundary conditions of thermal conductivity equation. Furthermore, surface soil conductive heat transfer equation of two-layer model is used to solve the soil thermal inertia so that the remote sensing thermal inertia method can be ap- plied to regions with better-covered vegetation, but usually only for the bare areas or worse vegetation covered areas. The model has been tested at several locations in the area of west Inner Mongolia. Comparing the simulation of the new model with the measurements obtained by apparent thermal inertia and by field test, the result shows that the inertia thermal model can be used to estimate soil moisture in more reasonable accuracy.

关键词： thermal model, thermal conductivity equation, soil initial, sensible flux, latent flux, two-layer model.

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Spatial heterogeneity of the driving forces of cropland change in china

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Science china earth {2. 2005年第12期48卷 2231-2240页

作者： LIU Xuhua1,2. WANG Jinfeng1, LIU Mingliang4,1 & MENG Bin1,2.3 1. Institute of Geographic sciences and Natural resources Research, Chinese Academy of sciences, beijing 100101, china 2. Graduate school of the Chinese Academy of sciences, beijing 100039, china 3. College of Arts and sciences of beijing Union university,{12., china 4. school of Forestry and Wildlife sciences, Auburn university, Auburn, Alabama, AL36849, USA 1. Institute of Geographic sciences and Natural resources Research Chinese Academy of Sciences 100101 Beijing China 2. Graduate school of the Chinese Academy of sciences 100039 Beijing China 3. school of Forestry and Wildlife sciences Auburn University Auburn AL36849 Alabama USA 4. College of Arts and sciences of beijing Union {2. 100083 Beijing China

By using digital satellite remote sensing data acquired in 1987―1989 and 1999―2.00 and GIS combined with the natural and socio-economic data, this paper drew an integrated zonation of the cropland change and its driving forces in china. The results indicated that the cropland change in the study period was constrained by geographical factors and driven by cli-mate change as well as socio-economic system. Moreover, the regional differences of the drivers for cropland change were significant. In the midwest of china, natural condition changes and geographical background were the main constraints and drivers, while in Eastern china, social and economic changes and economic policies were the main driving forces. The cropland loss was nationwide. The dominant factors to cause this decrease included buildup of developing area to attract foreign capital and technologies, changes of industry structure due to urban in-fluence, the change of employment notions thanks to living standard improvement, rapid ur-banization due to the expansion of cities and towns, the diminished farming net income partly because of the global warming effects, and the rapid economic growth stimulated by the con-venient transportation system. These factors interact and interdepend with each other to cause the cropland loss in china recently. The reasons for the increase of cropland were primarily the cultivation and deforestation by the farmers who want to increase income. This study on the mechnism of LUCC relied on the cropland change integrated classification considering the natural or human factors both inside and outside the region, which provides a new approach to study the integrated regionalization and LUCC mechanism.

关键词： land use change, driving force, integrated classification, spatial statistics, cropland, china.

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