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Structure and floristic composition of old-growth wet ev.rgreen forests of Nelliampathy Hills, Southern Western Ghats

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Journal of Forestry Research 2013年第1期24卷 37-46页

作者： v.S. Ramachandran k. Swarupanandan Forest Ecology and Biodiv.rsity Conserv.tion Div.sion Kerala Forest Research InstitutePeechiThrissur-680653KeralaIndia.

We analyze the structure and composition of old-growth wet ev.rgreen forest of Nelliampathy hills, the chain of hills lying immediately south of Palghat Gap, in the southern Western Ghats of India. We sampled 30 plots of 0.1 ha each （50 m × 20 m） at six locations enumerating all plants ？ 10 cm girth at breast height. We pooled the data and computed v.rious structural parameters. There were 152 species of 120 genera and 51 families of the study area. Of these, 118 （77%） were trees, 24 were climbers （16%） and 10 were shrubs （7%）. Species richness v.ried from 58–99 per 0.5 ha sample and Shannon indices of div.rsity ranged from 4.4 to 5.2. Fifty-nine per cent （89 species） of the species were Indian Sub-continent elements and 34% （51 species） are endemic to the Western Ghats. Fifteen species are listed in v.rious threat categories. Aglaia and Litsea were the most species-rich genera. Numbers of families ranged from 27–43 per 0.5 ha sample. Euphorbiaceae and Lauraceae were the most species-rich families. Stand density v.ried from 1714 to 2244 stems·ha？1 and basal area from 53.6 to 102.1 m2·ha？1. The v.getation was dominated by 3–6 species and six dominance patterns characterized the species composition within the hill complex. The old-growth ev.rgreen forests of Nelliampathy exist as small fragments rich in biodiv.rsity and can be used as benchmark. for comparison with disturbed forests.

关键词： Old-growth ev.rgreen forest Nelliampathy Western Ghats species richness tree density relativ. abundance stand structure.

Express Methods for Measurement of Electroconductiv.ty of Semiconductor Layered Crystal

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Chinese Physics Letters 2015年第11期32卷 114-117页

作者： FILIPPOv.v. v. v.ASOv.A. N. Department of Physics Lipetsk State Pedagogical University Lipetsk 398020 Russian Federation Department of Natural Sciences and Technical Disciplines the Branch in Lipetsk of Moscow State University of Technologies and Management Lipetsk 398006 Russian Federation

We describe theoretically the grounded method of measuring the conductiv.ty of anisotropic layered semiconductor materials. The suggested method implies the use of a four-probe testing dev.ce with a linear arrangement of probes. The final expressions for identifying the electrical conductiv.ty are presented in the form of a series of analytic functions. The suggested method is experimentally v.rified, and practical recommendations of how to apply it are also prov.ded.

关键词： Express Methods for Measurement of Electroconductiv.ty of Semiconductor Layered Crystal

Lunar surface mineralogy using hyperspectral data： Implications for primordial crust in the Earth-Moon system

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Geoscience Frontiers 2017年第3期8卷 457-465页

作者： v. Siv.k.mar Centre for Dev.lopment of Adv.nced Computing (C-DAC) CDAC Innovation Park Pune 411008 India Department of Geology Periyar University Salem 636011 India Department of Industries and Earth Sciences Tamil University Tanjore 613010 India Centre for Tectonics Resources and Exploration Department of Earth Sciences University of Adelaide SA 5005 Australia School of Earth Sciences and Resources China University of Geosciences Belting 29 Xueyuan Road Beijing 100083 China Faculty of Science Kochi University Kochi 780-8520 Japan

Mineralogy of the Lunar surface prov.des important clues for understanding the composition and ev.- lution of the primordial crust in the Earth-Moon system. The primary rock.forming minerals on the Moon such as pyroxene, oliv.ne and plagioclase are potential tools to ev.luate the Lunar Magma Ocean （LMO） hypothesis. Here we use the data from Moon Mineralogy Mapper （M3） onboard the Chandrayaan- 1 project of India, which prov.des v.sible/Near Infra Red （NIR） spectral data （hyperspectral data） of the Lunar surface to gain insights on the surface mineralogy. Band shaping and spectral profiling methods are used for identifying minerals in fiv. sites： the Moscov.ense basin, Orientale basin, Apollo basin, Wegener crater-highland, and Hertzsprung basin. The common presence of plagioclase in these sites is in conformity with the anorthositic composition of the Lunar crust. Pyroxenes, oliv.ne and Fe-Mg-spinel from the sample sites indicate the presence of gabbroic and basaltic components. The compositional difference in pyroxenes suggests magmatic differentiation on the Lunar surface. Oliv.ne contains OH/H20 band, indicating hydrous phase in the primordial magmas.

关键词： Moon Mineralogy Mapper Lunar Magma Ocean Primordial crust Magmatic differentiation Chandrayaan-1

Estimation of Pore Charge on Zirconia Membrane Prepared by Sol-gel Route Using Zeta Potential Measurement

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Journal of Materials Science & Technology 1998年第5期14卷 425-428页

作者： Seshadri, k.S. Ahmed, Jallel k.sav.moorthy, R. v.ratharajan, k. Sriniv.san, M.P. k.ishnasamy, v. Centralised Waste Management Facility Kalpakkam Tkmil Nadu -603 102 India Material Science Laboratory IGCAR Kalpakkam India Water and Steam Chemistry Laboratory IGCAR Kalpakkam India Dept. of Chemical Engineering Anna University Chennai India

Zirconia membrane was prepared in the sol-gel process by filtering v.scous colloidal zirconia sol through microporous alumina support and gelling followed by sintering at 743 k. The scanning electron micrograph shows that mean pore size is 543 nm and pore density is 1.47 multiplied by 10**7/cm**2. The filtration characteristics during membrane layer formation show that the membrane layer formation starts after 40 min. The membrane layer thick.ess and the porosity of the membrane were determined grav.metrically by finding out the amount of water present in the pores. The membrane layer thick.ess was found to be 3 micron and the porosity was found out to be 0.38. The pore charge density was estimated from the particle charge density, pore density, pore diameter and the thick.ess of the membrane layer. (Edited author abstract) 5 Refs.

关键词： Zirconia

Modeling corrosion behav.or of gas tungsten arc welded titanium alloy

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中国有色金属学会会刊：英文版 2007年第4期17卷 676-680页

作者： M. Balasubramanian v. Jay abalan v. Balasubramanian Department of Mechanical Engineering Maamallan Institute of Technology Anna University Department of Manufacturing Engineering Anna University Department of Manufacturing Engineering Annamalai University

The pitting corrosion characteristics of pulse TIG welded Ti-6Al-4v.titanium alloy in marine env.ronment were explained. Besides the rapid adv.nce of titanium metallurgy, this is also due to the successful solution of problems associated with the dev.lopment of titanium alloy welding. The preferred welding process of titanium alloy is frequently gas tungsten arc(GTA) welding due to its comparativ.ly easier applicability and better economy. In the case of single pass GTA welding of thinner section of this alloy, the pulsed current has been found beneficial due to its adv.ntages ov.r the conv.ntional continuous current process. The benefit of the process is utilized to obtain better quality titanium weldments. Four factors, fiv. lev.ls, central composite, rotatable design matrix are used to optimize the required number of experiments. The mathematical models hav. been dev.loped by response surface method(RSM). The results rev.al that the titanium alloy can form a protectiv. scale in marine env.ronment and is resistant to pitting corrosion. Experimental results are prov.ded to illustrate the proposed approach.

关键词：钛合金脉冲电流钨电极惰性气体保护焊腐蚀行为

Charged particle propagation through nanostructures and associated radiation

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Nuclear Science and Techniques 2004年第2期15卷 65-85页

作者： N.k. ZHEv.GO v. I. GLEBOv Institute of High Technology in Experimental Machinery Russian Research Centre "Kurchatov Institute" Moscow 123182 RussiaInstitute of High Technology in Experimental MachineryRussian Research Centre "Kurchatov Institute" Moscow 123182 Russia

In this report, using computer simulations, we inv.stigate the channeling of high-energy charged parti- cles in nanotube ropes and fullerites and estimate the capability of bent nanocrystals to deflect a particle beam. We also discuss electromagnetic radiation arising both from the non-uniform motion of the particles in the electrostatic potential of aligned atoms and from the transient polarization of the medium caused by the particles.

关键词：纳米结构带电粒子传播方式计算机仿真电磁辐射瞬时偏振固体物理学沟道效应

Some hydrodynamic aspects of 3-phase inv.rse fluidized bed

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China Particuology 2007年第5期5卷 351-356页

作者： k.ishna S.v.S.R. Bandaru D.v.S. Murthy k. k.ishnaiah Department of Chemical Engineering Indian Institute of Technology Madras

Hydrodynamics of 3-phase inv.rse fluidized bed is studied experimentally using low density particles for different liquid and gas v.locities. The hydrodynamic characteristics studied include pressure drop, minimum liquid and gas fluidization v.locities and phase holdups. The minimum liquid fluidization v.locity determined using the bed pressure gradient, decreases with increase in gas v.locity. The axial profiles of phase holdups shows that the liquid holdup increases along the bed height, whereas the solid holdup decreases down the bed. Howev.r, the gas holdup is almost uniform in the bed.

关键词： Inv.rse fluidization Inv.rse fluidized bed Hydrodynamics Phase holdup Axial holdup

Nonlinear dynamics of MEMS turning fork.gyroscope

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Science China(Technological Sciences) 2011年第5期54卷 1078-1083页

作者： Yu. G. MARTYNENk. I. v. MERk.RYEv.v. v. PODALk.v Institute of Mechanics Lomonosov Moscow State University Moscow Power Engineering Institute (Technical Univ.rsity)

Accuracy improv.ment of MEMS gyros requires not only microelectronic dev.lopment but also the inv.stigations of th mathematical model of sensitiv. element dynamics. In the present paper, we study the errors of the v.brating microgyroscop which arise because of nonlinear dynamics of a sensitiv. element. A MEMS tuning fork.gyroscope with elastic rods is consid ered. Nonlinear differential equations of bending v.brations of sensitiv. element on the mov.ng basis are deriv.d. Free nonlin ear v.brations of gyroscopes as the flexible rod are studied. Nonlinear dynamics of gyroscope on the mov.ng basis are inv.sti gated by asymptotic two scales method. Sensitiv. element frequencies split on two frequencies resulted from slowly changin angular v.locity are tak.n into account in the equations of zero approximation. The differential equations for slowly changin amplitudes and phases of two normal wav.s of the oscillations measured by capacitor gauges and an electronic contour of th dev.ce are obtained from the equations of the first approximation.

关键词： control of gyro oscillations split of frequencies identification av.raging method two scales method stability

Effect of MWCNT reinforcement on the precipitation-hardening behav.or of AA2219

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International Journal of Minerals,Metallurgy and Materials 2018年第1期25卷 53-61页

作者： Shijo Thomas Umasank.r v. School of Mechanical and Building Sciences VIT University

Aluminum alloy matrix composites hav. found a predominant place in research, and their applications are explored in almost all industries. The aerospace industry has been using precipitation-hardenable alloys in structural applications. Howev.r, insufficient literature is av.ilable on the influence of multiwalled carbon nanotubes （MWCNTs） on precipitation-hardenable alloy composite materials; thus, this work.was designed to elucidate the effect on MWCNT reinforcement on AA2219 with and without precipitation hardening. Reinforcement with MWCNTs has been reported to accelerate precipitation and to achiev. greater hardness within a much shorter time. The addition of 0.75wt% MWCNTs resulted in maximal hardness at 90 min, which is approximately 27% of improv.ment ov.r the maximum hardness achiev.d by the corresponding monolithic alloy after 10 h of aging. The sample reinforced with 0.75wt% MWCNTs showed an improv.- ment of 82% in hardness by solutionizing and aging compared to that achiev.d by sintering.

关键词： aluminum metal-matrix composites multi walled carbon nanotubes (MWCNT) powder metallurgy heat treatment precipitation hardening