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seasonal variations of rotifers from a high altitude urban shallow water body, La Cantera Oriente (Mexico City, Mexico)

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Chinese Journal of Oceanology and Limnology 2017年第6期35卷 1387-1397页

作者： sergio González GUTIERREZ s.s.s. sARMA s. NANDINI Postgraduate Programme in Marine sciences and Limnology National Autonomous University of Mexico Circuito Exterior sin Ciudad Universitaria Mexico City 04510 Mexico Laboratory of Aquatic Zoology Division of Research & Postgraduate Studies National Autonomous University of Mexico Campus Iztacala Av. de los Barrios No.1 AP 314 Los Reyes Tlalnepantla State of Mexico 54090 Mexico

La Cantera Oriente is a shallow freshwater volcanic water body located at an altitude of 2 270 m above sea level in the Ecological Reserve of san Angel Pedregal of Mexico City （Mexico）. In order to ensure the conservation of its biological heritage including zooplankton, the present work was undertaken to quantify the seasonal changes in the diversity and density of rotifers and the selected physico- chemical variables during 2013-2014. Qualitative analysis of the zooplankton samples yielded 68 rotifer species which represented 24 genera in 15 families. Brachionus calyciflorus Pallas, 1766, B. quadridentatus Hermann, 1783, Polyarthra vulgaris Carlin, 1943, Lecane closterocerca （schmarda, 1859） and Keratella cochlearis （Gosse, 1851） were the most common species. Preston plots of species frequency-density revealed that as many as 30% of the rotifer taxa were dominant throughout the year. The species with high population densities were Brachionus quadridentatus, Lecane closterocerca, Keratella cochlearis, and Lepadellapatella; their peak densities were 2 000, 1 000, 180 and 90 ind./L, all occurring in summer. Canonical correspondence analysis showed that Platyias quadricornis was related to the concentration of phosphates available in the environment and the conductivity, while B. quadridentatus was positively correlated with chlorophyll-a. The trophic status of the lake was eutrophic based on Chl-a content but oligotrophic with relation to the Braehionus： Trichocerca ratio.

关键词： high altitude zooplankton seasonal density dynamics limnology rotifera

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Plant Communities and Factors Responsible for Vegetation Pattern in an Alpine Area of the Northwestern Himalaya

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Journal of Mountain science 2011年第6期8卷 817-826页

作者： Man s.RANA s.s.sAMANT Y.s.RAWAT Department of Plant science Government Degree College G.B.Pant Institute of Himalayan Environment & Development Department of Botany D.S.B.CampusKumaun University

The study intended to describe the alpine vegetation of a protected area of the northwestern Himalaya and identify the important environmental variables responsible for species *** placed random plots covering different habitats and altitude to record species composition and environmental *** was classified using hierarchical cluster analysis and vegetation-environment relationships were evaluated with Canonical Correspondence *** communities,each in alpine shrub and meadows were delineated and well justified in the ordination *** species for the different communities were *** species richness and diversity were found in community IV among shrub communities and community II among the *** environmental variables explained 61.5% variation in shrub vegetation and 59.8% variation in *** variables explained higher variability (～35%) than spatial variables (～21%) in both shrubs and ***,among the spatial variables and carbon/nitrogen ratio and nitrogen among the soil variables explained maximum *** 40% variations left *** and species diversity among the other variables had significant correlation with ordination *** showed that altitude and C/N ratio played a significant role in species *** sampling efforts and inclusion of other non-studied variables are also suggested for better understanding.

关键词： species diversity Indicator species Environmental variable Ordination Explainedvariation

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Micro-synchrophasor based special protection scheme for distribution system automation in a smart city

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Protection and Control of Modern Power systems 2020年第1期5卷 97-110页

作者： Deepa s.Kumar savier J.s Biju s.s Dept of Electrical Engineering College of EngineeringTrivandrumKeralaIndia 400/220kV substation Powergrid Corporation of India Ltd.TrivandrumKeralaIndia Power system Operations Kerala State Electricity Board Ltd.KeralaIndia

Introduction:Aspects of power system protection which contributes to mal-operations and blackouts can be improved by supervision of system behavior and response based analysis rather than condition-based or event-based analysis using wide area measurements based on synchrophasor *** paper explores the application of micro-Phasor Measurement Unit for time synchronized real-time distribution network monitoring and agile decision support schemes for system prognosis and *** description:The scheme is proposed as part of a project on“Power system Voltage stability Analysis using synchrophasors in Distribution system of Kerala Grid”at Kerala state Electricity Board *** actual grid occurrence during the severe tropical cyclone Ockhi,is considered as the base case which motivated the *** and evaluation:A voltage stability index(VsI)based special protection scheme(sPs)for radial distribution network at a proposed smart city is presented in the present *** proposed special protection scheme on actual implementation can use data from proposed local micro-Phasor Measurement *** PMU is proposed to be placed at one of the key nodes of the distribution system network in the ***:The VsI is derived using local phasor values and is used to initiate a special Protection scheme for N-1 contingency at the key node,so as to ensure availability of the most essential feeder which provides supply to a hospital campus housing several health institutes of prime *** voltage stability index derived is tested and sPs is validated using real-time grid data.

关键词： Micro-phasor measurement unit Power system protection Voltage stability Power system stability Power distribution smart grids

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The bound state solution for the Morse potential with a localized mass profile

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Chinese Physics B 2016年第10期25卷 35-38页

作者： s Miraboutalebi Department of Physics Islamic Azad UniversityTehran North Branch

We investigate an analytical solution for the schr o¨dinger equation with a position-dependent mass distribution, with the Morse potential via Laplace transformations. We considered a mass function localized around the equilibrium *** mass distribution depends on the energy spectrum of the state and the intrinsic parameters of the Morse potential. An exact bound state solution is obtained in the presence of this mass distribution.

关键词： schrdinger equation Morse potential Laplace transformation method position-dependent mass

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Convergence of COVID-19 and recurrent stroke:In-hospital mortality risks explored

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World Journal of Virology 2025年第1期14卷 5-8页

作者： Basavraj s Nagoba shree V Dhotre Ajay M Gavkare sachin s Mumbre Pradnya s Dhotre Department of Microbiology Maharashtra Institute of Medical Sciences and Research(Medical College)Latur 413531India Department of Microbiology Ashwini Rural Medical CollegeSolapur 413001India Department of Community Medicine Ashwini Rural Medical CollegeSolapur 413001India Department of Biochemistry Ashwini Rural Medical CollegeSolapur 413001India

This editorial comments on the article by Desai et al,which investigates the impact of coronavirus disease 2019(COVID-19)on in-hospital mortality among patients with recurrent stroke using data from the 2020 National Inpatient *** findings reveal significantly higher mortality rates in COVID-19-positive patients compared to non-COVID-19 patients,particularly among middle-aged individuals,males,and ethnic *** editorial explores the underlying mechanisms contributing to these outcomes and discusses the clinical implications for targeted management strategies in high-risk *** results emphasize the need for comprehensive approaches to mitigate the heightened risks faced by recurrent stroke patients during the COVID-19 pandemic.

关键词： Recurrent stroke COVID-19 In-hospital mortality Nationwide analysis stroke admissions Infectious diseases Chronic health conditions Hypercoagulability

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Low-cycle Fatigue Behaviors of an As-extruded Mg-12%Gd-3%Y-0.5%Zr Alloy

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Journal of Materials science & Technology 2013年第8期29卷 775-780页

作者： s.M.Yin s.X.Li shenyang University of Chemical Technology shenyang National Laboratory for Materials science Institute of Metal ResearchChinese Academy of Sciences

Cyclic deformation and fatigue behaviors of Mg-12%Gd-3%Y-0.5%Zr （wt%, GW123K） alloy were investigated at room temperature under axial cyclic loading in strain controlled condition. It is shown that conventional extruded GW123K alloy maintained cyclic stability at strain amplitudes ranging from 2 × 10^-3 to 10^-2. The pronounced symmetric hysteresis loops were also observed during cyclic loading. Fracture surface observations indicated that fatigue cracks mainly initiated at large Gd-riched phase or at inclusion clusters at surface or subsurface, and grain boundary （GB） and slip bands （sBs） are also preferential sites for micro-crack incubation.

关键词： Magnesium alloy Low-cycle fatigue Cyclic stabilization Fatigue crack Fractography

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Photocatalytic degradation of RhB and TNT and photocatalytic water splitting with CZTs microparticles

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Journal of semiconductors 2015年第7期36卷 29-33页

作者： s.s.shinde Hanyang University

Cu2Znsns4 （CZTs） is a main candidate material for solar energy conversion through both photovoltaics and photocatalysis based on environmentally friendly elements and with a direct band gap of 1.5 eV. We report the synthesis of quasi CUEZnsns4 microparticles with unprecedented narrow size distributions. The structural, morphological and core level analysis has been carried out by XRD, sEM and XPs techniques. These microparticles have shown excellent photocatalytic activity toward degradation ofRhodamine B dye （RhB） and TNT under visible light. The extent of mineralization has been analyzed by COD and TOC values. Photocatalytic water splitting for HE generation has also been reported.

关键词： Rhodamine B TNT CZTs photocatalysis H2 production

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Effect of Colouring Process on Pitting susceptibility of Austenitic stainless steel

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Journal of Materials science & Technology 2008年第3期24卷 400-406页

作者： s.s.Mahmoud M.M.Ahmed Chemistry Department University College of Girls for ArtsScience and EducationAin Shams University

Colouring of the austenitic stainless steel alloy （20.45% Cr, 8.57% Ni） was carried out in NaNO3-KNO3 eutectic melt without and with additions of Na2O2, NaCl and their mixtures at different temperatures ranging from 400-600℃, under open-circuit and galvanostatic anodic polarization conditions. The produced colours greatly depend on the thickness of oxide films, which in turn depends on the composition of the molten bath and its temperature. The more attractive, bright, adherent and uniform coloured oxide films can be obtained at 400, 450 and 500℃ in molten nitrate bath containing NaCl and Na2O2 mixtures. The pitting corrosion susceptibility of the coloured oxide films was tested in FeCl3 and NaCl as corrosive media. The obtained results indicate that the pitting corrosion susceptibility of the coloured oxide films greatly depends on the previous operating conditions of the colouring process of the stainless steel specimens such as the composition of molten bath, temperature and technique of colouring process.

关键词： stainless steel alloy Pitting corrosion Colouring processes

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LINEARIZATION OF A NONLINEAR PERIODIC BOUNDARY CONDITION RELATED TO CORROsION MODELING

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Journal of Computational Mathematics 2007年第6期25卷 645-660页

作者： Y. s. Bhat s. Moskow Institute for Mathematics and its Applications Univ. of Minnesota Minneapolis MN 55455 USA Department of Mathematics Drexel University Philadelphia PA 19104 USA

We study galvanic currents on a heterogeneous surface. In electrochemistry, the oxidation-reduction reaction producing the current is commonly modeled by a nonlinear elliptic boundary value problem. The boundary condition is of exponential type with periodically varying parameters. We construct an approximation by first homogenizing the problem, and then linearizing about the homogenized solution. This approximation is far more accurate than both previous approximations or direct linearization. We establish convergence estimates for both the two and three-dimensional case and provide two-dimensional numerical experiments.

关键词： Galvanic corrosion Homogenization Nonlinear elliptic boundary value problem Butler-Volmer boundary condition Robin boundary condition.

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Mn_(3)O_(4) based materials for electrochemical supercapacitors: Basic principles, charge storage mechanism, progress, and perspectives

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Journal of Materials science & Technology 2022年第35期130卷 227-248页

作者： s.A.Beknalkar A.M.Teli T.s.Bhat K.K.Pawar s.s.Patil N.s.Harale J.C.shin P.s.Patil Thin Film Materials Laboratory Department of PhysicsShivaji UniversityKolhapur 416-009India Division of Electronics and Electrical Engineering Dongguk University-SeoulSeoul 04620South Korea school of Nano-science and Technology Shivaji UniversityKolhapur 416-009India Department of Physics Sadguru Gadage MaharajCollege KaradSataraMississippi 415110India

The captivating properties of supercapacitors(sCs) such as high power and reasonably high energy densities made them stand up as a versatile solution to emerging energy storage ***,everyone is in pursuit of improvisation of the energy storage characteristics of *** or manganese oxide(Mn_(3)O_(4)) is a widely studied electrode material considering its fascinating features such as high theoretical capacitance(1370 F/g),variable oxidization states,prominent Jahn-Teller effect,broad potential window,environmentally benign and cost-effectiveness.A lot of research has been carried out on this material to unfold and improve its electrochemical *** this review,comprehensive knowledge and innovative attempts taken to improve its energy storage of Mn_(3)O_(4)material are ***,the basic properties concerned with electrochemical charge storage such as valance states,crystal structure,band diagram and energy storage mechanism are discussed,followed by putting forth the limitations of Mn_(3)O_(4).Later on,various strategies adopted to improve the electrochemical attributes of Mn_(3)O_(4)such as making composite with carbon-based materials,metal-based materials,polymers or doping metal atoms are ***,remarks on key scientific points and perspectives for further development of energy storage in Mn_(3)O_(4)conclude this review.

关键词： supercapacitors Nanostructures Mn_(3)O_(4)based composites

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