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Chinese Science Bulletin 1999年第S2期44卷 7-8页

作者： m. j. Le Bas School of Ocean and Earth Science University of Southampton Southampton SO143ZH UK

THE origin of the giant Bayan Obo REE-Nb-Fe ore deposit has been under m.ch debate since its discoveryas an iron deposit by Prof. Ding Daoheng in 1927. The m.in dispute is concentrated on the genesis of theore-hosted dolom.te m.rbles of the deposit, Som. authors considered them.to be sedim.ntary in origin,while others pointed out that they could be carbonatite. However, there are very few researches concerning the com.ositions of carbonate m.nerals which m.y provide a direct clue to their petrogenesis. Herewe show the variations of com.ositions in carbonate m.nerals from.Bayan Obo. Carbonate rocks from.Bayan Obo, Inner m.ngolia, could be divided into sedim.ntary lim.stone anddolostone (H8_s), coarse-grained dolom.te m.rble (H8_c), fine-grained dolom.te m.rble (H8_f) and carbonatite dykes (D) based on their texture, structure, m.neral progenesis and occurrences. H8_s thatshows weak m.tam.rphism.and deform.tion is distributed to the north of the Kuangou fault, occurring

关键词： carbonate m.nerals dolom.te carbonatite Bayan Obo.

Effect of Plasm. on the Zeta Potential of Cotton Fabrics

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Plasm. Science and Technology 2013年第5期15卷 455-458页

作者： A. RASHIDI S. SHAHIDI m. GHORANNEVISS S. DALALSHARIFI j. WIENER Departm.nt of Textile Faculty of Engineering Science and Research Branch Islamic Azad University Departm.nt of Textile Faculty of Engineering Islamic Azad University Arak Branch Plasm. Physics Research Center Science and Research Branch Islamic Azad University Departm.nt of Textile Chem.stry Faculty of Textile Technical University of Liberec

In this work, the effect of a low-tem.erature plasm. on the zeta potential of cotton fabric was studied. The silver particle absorption on cotton fabric when m.dified by a low-tem.erature plasm. was also investigated. The m.dification consisted of plasm. pre functionalization followed by a one-step wet treatm.nt with silver nitrate solution. The process was perform.d in a low-tem.erature plasm. m.dium. using a m.gnetron sputtering device. Oxygen and nitrogen were used as working gases in the system. and the results were com.ared. After preparing the sam.les, the zeta potentials of the untreated and plasm.-treated cotton under a constant pH value solution were estim.ted and com.ared. Also, Fourier transform.infrared spec troscopy （FTIR） was used to exam.ne the functional groups of the corresponding sam.les. The am.unts of silver absorption on plasm. treated and untreated cotton were exam.ned using the energy dispersive X-ray （EDX） m.thod. The results show that the am.unt of zeta potential for the nitrogen plasm. treated sam.le is less and the absorption of silver particles by cotton can be increased strongly with nitrogen plasm. treatm.nt.

关键词： plasm. zeta-potential fabric

An underlying geom.trical m.nifold for Ham.ltonian m.chanics

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Frontiers of physics 2017年第1期12卷 123-131页

作者： L. P. Horwitz A. Yahalom.j. Levitan m. Lewkowicz School of Physics Tel Aviv University Ramat Aviv 69978 Israel Departm.nt of Physics Bar llan University Ramat Gan 52900 Israel Departm.nt of Physics Ariel University Ariel 40700 Israel Departm.nt of Electrical and Electronic Engineering Ariel University Ariel 40700 Israel

We show that there exists an underlying m.nifold with a conform.l m.tric and com.atible connection form. and a m.tric type Ham.ltonian （which we call the geom.trical picture）, that can be put into correspondence with the usual Ham.lton-Lagrange m.chanics. The requirem.nt of dynam.cal equiva- lence of the two types of Ham.ltonians, that the m.m.nta generated by the two pictures be equal for all tim.s, is sufficient to determ.ne an expansion of the conform.l factor, defined on the geom.trical coordinate representation, in its dom.in of analyticity with coefficients to all orders determ.ned by functions of the potential of the Ham.ltonian-Lagrange picture, defined on the Ham.lton-Lagrange coordinate representation, and its derivatives. Conversely, if the conform.l function is known, the potential of a Ham.lton-Lagrange picture can be determ.ned in a sim.lar way. We show that arbi- trary local variations of the orbits in the Ham.lton-Lagrange picture can be generated by variations along geodesics in the geom.trical picture and establish a correspondence which provides a basis for understanding how the instability in the geom.trical picture is m.nifested in the instability of the the original Ham.ltonian m.tion.

关键词： geom.trical Ham.ltonian stability analysis coordinate m.pping Riem.nn-Euclidean Ham.ltonian equivalence

Unsteady m.xed convective heat transfer of two im.iscible fluids confined between long vertical wavy wall and parallel flat wall

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Applied m.them.tics and m.chanics(English Edition) 2012年第7期33卷 931-950页

作者： j. C. Um.VATHI I. C. LIU m. SHEKAR Departm.nt of m.them.tics Gulbarga University Departm.nt of Civil Engineering National Chi Nan University

The com.ined effects of therm.l and m.ss convection of viscous incom. pressible and im.iscible fluids through a vertical wavy wall and a sm.oth flat wall are analyzed. The dim.nsionless governing equations are perturbed into a m.an part （the zeroth-order） and a perturbed part （the first-order）. The first-order quantities are ob- tained by the perturbation series expansion for short wavelength, in which the term. of the exponential order arise. The analytical expressions for the zeroth-order, the first-order, and the total solutions are obtained. The num.rical com.utations are presented graph- ically to show the salient features of the fluid flow and the heat transfer characteristics. Separate solutions are m.tched at the interface by using suitable m.tching conditions. The shear stress and the Nusselt num.er are also analyzed for variations of the governing param.ters. It is observed that the Grashof num.er, the viscosity ratio, the width ratio, and the conductivity ratio prom.te the velocity parallel to the flow direction. A reversal effect is observed for the velocity perpendicular to the flow direction.

关键词： m.xed convection wavy wall im.iscible fluid perturbation m.thod

What are the evolutionary origins of stom.tal responses to abscisic acid in land plants?

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j.urnal of Integrative Plant Biology 2017年第4期59卷 240-260页

作者： Frances C. Sussm.lch Tim.thy j. Brodribb Scott A. m. m.Adam School of Biological Sciences University of Tasmania Hobart Tasmania Australia

The evolution of active stom.tal closure in response to leaf water deficit, m.diated by the horm.ne abscisic acid （ABA）, has been the subj.ct of recent debate. Two different m.dels for the tim.ng of the evolution of this response recur in the literature. A single-step m.del for stom.tal control suggests that stom.ta evolved active, ABA- m.diated control of stom.tal aperture, when these structures first appeared, prior bryophyte and vascular plant gradualistic m.del for stom.tal to the divergence of neages. In contrast, a control proposes that the m.st basal vascular plant stom.ta responded passively to changes in leaf water status. This m.del suggests that active ABA-driven m.chanism. for stom.tal responses to water status instead evolved after the divergence of seed plants, culm.nating in the com.lex, ABA-m.diated responses observed in m.dern angiosperm.. Here we review the findings that form.the basis for these two m.dels, including recent work that provides critical m.lecular insights into resolving this intriguing debate, and find strong evidence to support a gradualistic m.del for stom.tal evolution.

关键词： ABA What are the evolutionary origins of stom.tal responses to abscisic acid in land plants acid

ESTIm.TING NORTH PACIFIC SUm.ER SEA-LEVEL PRESSURE BACK TO 1600 USING PROXY CLIm.TE RECORDS FROm.CHINA AND NORTH Am.RICA

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Advances in Atm.spheric Sciences 1987年第1期4卷 74-84页

作者：吴祥定,j. m. Lough Institute of Geography Academ.a Sinica Beij.ng Laboratory of Tree-Ring Research University of Arizona Tucson AZ 85719 U.S.A.

Sea-level pressure variations over the North Pacific Ocean influence the surface clim.te conditions of China and western North Am.rica. Docum.ntary records of precipitation in China data back to the m.d-15th century, and a well-replicated network of tree-ring chronologies from.western North Am.rica dates to the early 17th century. These proxy clim.te records are used separately and together to estim.te sea-level pressure variations over the North Pacific back to 1600 A.D. The m.dels are calibrated over the period 1899 to 1950 and verified over the independent period, 1951 to 1963. The best estim.tes, derived from.predictors in China and western North Am.rica, calibrate 44.7% of sum.er sea-level pressure variance. The study dem.nstrates the potential of com.ining different proxy data sources to derive estim.tes of past clim.te.

关键词： over ESTIm.TING NORTH PACIFIC SUm.ER SEA-LEVEL PRESSURE BACK TO 1600 USING PROXY CLIm.TE RECORDS FROm.CHINA AND NORTH Am.RICA TR ARm. RE SEA

Fertilizer-Induced Advances in Corn Growth Stage and Quantitative Definitions of Nitrogen Deficiencies

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Pedosphere 2008年第1期18卷 60-68页

作者： j. ZHANG A. m. BLACKm.R P. m. KYVERYGA B. W. VAN DE WOESTYNE T. m. BLACKm.R Departm.nt of Agronom. Iowa State University Ames IA 50011 (USA) Iowa Soybean Association 4554 114th Street Urbandale IA 50322 (USA) j.hn Deere Ag m.nagem.nt Solutions 140 114th Street Urbandale IA 50322 (USA) Statistieal Consulting Center 130 MM Wright State University Dayton OH 45435 (USA)

Evidence that nitrogen (N) fertilization tends to accelerate m.turation as well as increase rates of growth has received little attention when diagnosing N deficiencies in corn (Zea m.ys L.).Such a tendency could be a potential source of errors when the diagnosis is solely based on com.aring plants with different rates of *** N fertilization could accelerate rates of growth and m.turation was tested in a field study with 12 paired plots representing relatively large variability in soil properties and landscape *** plots were located under conditions where preplant N fertilization reduced or avoided tem.orary N shortages for som. plants but did not reduce for other plants early in the *** m.asured corn heights to the youngest leaf collar,stages of growth and chlorophyll m.ter readings (Cm.s). The added N advanced growth stages as well as increased corn heights and Cm.s at any given *** effects on corn heights,growth stages and ear weights were statistically significant (Pm.orary shortage of N within a growth stage m.ght be partially offset by longer periods of growth within that stage to physiological *** shortages of N,therefore,m.y produce sym.tom. of N deficiency in situations where subsequent additions of N should not be expected to increase *** of these two som.what different effects (i.e.,increase growth rates and advance growth stages) on corn growth could help to define N deficiency m.re precisely and to im.rove the accuracy of diagnosing N status in production agriculture.

关键词： chlorophyll corn fertilizer growth stage nitrogen deficiency

Particle size distribution and shape control of Au nanoparticles used for particle gun

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Frontiers of Chem.cal Science and Engineering 2013年第1期7卷 60-64页

作者： S. Kida m. Ichij. j. Watanabe I. Hirasawa Graduate School of Advanced Sciencel Engineering Waseda University Tokyo 169-8555 Japan

Au nanoparticles are expected for the m.dia to transfer genes into plants. However, the control of particle size distribution （PSD） and shape of Au nanoparticles is too difficult to design and prepare particles with suitable quality for the gene supporting m.dia. Reduction crystal- lization experim.nts were perform.d in aqueous solution in order to clarify the effect of feeding conditions such as feeding profile, feeding rate, and feeding am.unt on PSD and shape of Au nanopartieles. Ascorbic acid （AsA） was selected as a reducing agent because it is safe for plants. Au particles of 50nm. 50-200nm. and 150-400nm.were obtained in batch operation, single-j.t, and double-j.t, respectively. m.reover, in single-j.t and double-j.t, the m.an size of the obtained Au particles increases with the decrease of feeding rate or the increase of feeding am.unt. It is concluded that PSD of Au nanoparticles can be controlled in the range of 50-400 nm.by changing feeding conditions of AsA and HAuCl4 aqueous solution.

关键词： reduction crystallization particle size distri- bution gene transferring m.dia

m.m.ntum.Transport in DIII-D Discharges with and Without m.gnetohydrodynam.cs （m.D） Activity

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Plasm. Science and Technology 2009年第1期11卷 127-130页

作者：任启龙 m. S. CHU L. L. LAO H. St. j.HN R. LAHAYE Y. m. j.ON 张澄周登李国强 j. m. PARK j. S. DEGRASSIE Institute of Plasm. Physics Chinese Academy of Sciences Hefei 230031 China General Atom.cs San Diego CA USA Oak Ridge Institute for Science and Education Oak Ridge TN USA Oak Ridge National Laboratory Oak Ridge TN USA

Two phases of a DIII-D discharge with and without m.gnetohydrodynam.cs （m.D） activity are analysed using ONETWO code. The toroidal m.m.ntum.flux is extracted from.experim.ntal data and com.ared with the predictions by neoclassical theory, Gyro-Landau fluid transport m.del （GLF23） and m.lti-m.de m.del （m.m.5）. It is found that without m.D activities GLF23 and m.m.5 provide a reasonable description while with m.D activity no m.del alone can fully describe the experim.ntal m.m.ntum.flux. For the phase with m.D activity a sim.le m.del of resonant m.gnetic drag is tested and it cannot fully explain the plasm. slowing down observed in experim.nt.

关键词： toroidal rotation m.D activity m.gnetic drag

Cellular m.delling using P system. and process algebra

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Progress in Natural Science:m.terials International 2007年第4期17卷 375-383页

作者： Francisco j. Rom.ro-Cam.ero m.rian Gheorghe Gabriel Ciobanu j.hn m. Auld m.rio j. Pérez-j.m.nez Research Group on Natural Com.uting Department of Computer Science and Artificial IntelligenceUniversity of SevilleAvda.Reina Mercedes41012 SevillaSpain Departm.nt of Com.uter Science The University of Sheffield Regent CourtPortobello StreetSheffield S1 4DPUK Rom.nian Academ. Institute of Computer ScienceBlvd. Carol I nr. 11700505IasiRomania

In this paper various m.lecular chem.cal interactions are m.delled under different com.utational paradigm.. P system. andπ-calculus are used to describe intra-cellular reactions like protein-protein interactions and ... 详细信息

关键词： cellular m.delling P system. process algebra.