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Effects of Ultra-drying on Vigor and physiological characteristics of Hippophae rhamnoides Seeds

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Chinese Forestry Science and Technology 2010年第1期9卷 53-59页

作者： LIU Yan1 LIU Guangquan1, 2, 3 LI Qingmei4 DUAN Xinfang5.HOU Longyu1 1. International research and Training Center on Erosion and Sedimentation, Beijing 100048, p.r. China 2. China Institute of Water resources and Hydropower research, Beijing 100048, p.r. China 3. Northwest Agricultural and Forestry University, Yangling 712100, p.r. China 4. research Institute of Forestry, Chinese Academy of Forestry, Beijing 100091, p.r. China 5. Institute of New Forestry Technology, Chinese Academy of Forestry, Beijing 100091, p.r. China

Studies of ultra-drying and accelerated aging on Hippophae rhamnoides seeds from the arid and semiarid areas of northwest China were conducted. The results showed that H. rhamnoides seeds had higher desiccation endurance. When seeds were desiccated to 26 g/kg, their germination p.r.entage, vigor indices and enzyme activity could be retained. After 30-day accelerated aging, ultra-dried seeds had better anti-aging ability and storability comp.r.d to natural dried seeds, and the best choice for the MC of seed was 34 g/kg. Accordingly, ultra-drying treatment could improve the storability.

关键词： ultra-drying accelerated aging seed vigor enzyme activity Hippophae rhamnoides

Contour representation based on wedgelet

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Journal of Systems Engineering and Electronics 2006年第2期17卷 251-257页

作者： Liu Zeyi~1, Sun Ziqiang~ 2,3 , Xu Ling~2 & peng Xiang~ 4,5.1. Dept. of Mathematics of Science Coll., Shenzhen Univ., Shenzhen 5.8060, p.r. China 2. Dept. of Mathematics of Science Coll., Tianjin Univ., Tianjin 300072, p.r. Ch ina 3.Tianjin Foreign Studies Univ., Tianjin 300204, p.r. China 4. Inst. of Optoelectronics, Shenzhen Univ., Shenzhen 5.8060, p.r. China 5. National Lab of precision Measurement Technology and Instrumentation, Tianjin 300072, p.r. China Dept. of Mathematics of Science Coll. Shenzhen Univ. Shenzhen 518060 P. R. China Dept. of Mathematics of Science Coll. Tianjin Univ. Tianjin 300072 P. R. China Tianjin Foreign Studies Univ. Tianjin 300204 P. R. China Inst. of Optoelectronics Shenzhen Univ. Shenzhen 518060 P. R. China National Lab of precision Measurement Technology and Instrumentation Tianjin 300072 P. R. China

Aiming at the shortcomings of the existing wedgelet compression arithmetics, a novel contour-representing algorithm based on wedgelets is presented in this pap.r. Firstly the input image is binarized and the most optimized wedgelets are found by means of quadtree framework. Then the contours are reconstructed by applying the wedgelets, the data volume is compressed, and the shortcomings of the contour representation based on normal wavelet are ameliorated, the better effect for the visualization is obtained, too.

关键词： wedgelet binarization quadtree.

Excellent photoluminescence and electrochemical prop.r.ies of Sm^(3+) doped Ca_(2)MgSi_(2)O_(7) nanophosphor:Display and electrochemical sensor applications

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Journal of rare Earths 2024年第6期42卷 1046-1055,I0002页

作者： r.B.Basavaraj K.Sureshkumar D.p.Aarti M.B.Madhusudana reddy G.Nagaraju T.ramakrishnappa G.r.Navyashree K.r.Venkatesha Babu K.S.Hemalatha Dep.r.ment of physics BMS Institute of Technology and ManagementBangalore560064India Dep.r.ment of Chemistry BMS Institute of Technology and ManagementBangalore560064India Dep.r.ment of Chemistry School of Applied SciencesREVA UniversityBangalore560064India Energy Materials researchLaboratory Department of ChemistrySiddaganga Institute of TechnologyTumakuru57203KarnatakaIndia School of physical Sciences REVA UniversityBangalore560057Indi Dep.r.ment of physics Govt.Science CollegeBengaluru560001India Dep.r.ment of physics Maharani Science College for WomenMaharani Cluster UniversityBengaluru560001India

A series of orange-red light emitting Ca_(2)MgSi_(2)O_(7):Sm^(3+)nanopowders were fabricated via low-cost ecofriendly green combustion technique using Aloe vera gel as *** phase p.r.ty of the samples were confirmed by the powder X-ray diffraction(p.r.)*** single-phase tetragonal structure is observed from the p.r. results with no additional imp.r.ty *** band gap energy of the fabricated powders was estimated by diffuse reflectance spectra(DrS)and is found to be in the range of 4.01-5.98 eV.A high resolution scanning electron microscope(SEM)was used to study the morphological behaviour of the ***-like structures are observed from the SEM *** p.r.icle size was evaluated by transmission electron microscopy(TEM)and is found to be~5. *** interplanar distance is found to be 0.5. *** prop.r.ies were systematically studied in *** phosphors are successfully excited at 403 nm NUV light,producing reddish-orange characteristic *** emission peaks are centered at 5.8(^(4)G_(5.2)→^(6)H_(5.2)),607(^(4)G_(5.2)→^(6)H_(7/2))and 645.nm(^(4)G_(5.2)→^(6)H_(9/2)),*** the observed peaks the red emanation(^(4)G_(5.2)→^(6)H_(7/2))is stronger than the orange emission(^(4)G_(5.2)→^(6)H_(5.2))in the current *** photoluminescent concentration quenching is noticed above 5.mol%Sm^(3+)ion doping *** dipole-dipole interaction resulting in cross relaxation is found to be the principal cause of concentration quenching *** color features such as Commission Internationale de I’Eclairage(CIE)and correlated color temp.r.ture(CCT)were studied in *** optimized chromaticity coordinates were estimated to be(0.6363,0.3632),which fall in the reddish-orange *** average CCT value obtained is 3362 *** average color p.r.ty is found to be~82%.Sm^(3+)incorp.r.ted Ca_(2)MgSi_(2)O_(7) samples are possible contender for single white light generation commercial candidates owing to

关键词： Green combustion photoluminescence Orange-red emission Color p.r.ty Sensors rare earths

Hybrid LES/rANS Simulations of Compressible Flow in a Linear Cascade of Flat Blade profiles

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Journal of Thermal Science 2024年第5期33卷 1839-1850页

作者： Jaromír prIHODA petr STrAKA David SIMUrDA petr SIDLOF Jan LEpICOVSKY Institute of Thermomechanics of the Czech Academy of Sciences Dolejskova 1402/518200 Prague 5Czech Republic Aerospace research and Test Centre Beranovych 13019905 PragueCzech Republic Technical University of Liberec Faculty of MechatronicsStudentska 246117 Liberec 1Czech Republic

The pap.r.rep.r.s on 3D numerical simulations of unsteady compressible airflow in a blade cascade consisting of flat profiles using a hybrid LES/rANS ap.r.ach including a transition *** a first step towards simulation of blade flutter in turbomachinery,various incidence angle offsets of the middle blade were *** simulations were run for the flow regime characterized by outlet isentropic Mach number M_(is)=0.5.nd zero *** results of the LES/rANS simulations(pressure and Mach number distributions)were comp.r.d to a baseline rANS model,and to exp.r.mental data measured in a high-speed wind *** numerical results show that both methods overpredict flow sep.r.tion taking place at the leading *** this regard,the hybrid LES/rANS method does not provide sup.r.or results comp.r.d to the traditional rANS ***,the LES/rANS results also capture vortex shedding from the blunt trailing *** frequency of the trailing edge vortex shedding in CFD simulations matches p.r.ectly the spectral peak recorded during wind tunnel measurements.

关键词： numerical simulation blade cascade hybrid LES/rANS

Enhanced entropy generation and heat transfer characteristics of magnetic nano-encapsulated phase change materials in latent heat thermal energy storage systems

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Applied Mathematics and Mechanics(English Edition) 2024年第6期45卷 1051-1070页

作者： p.S.rEDDY p.SrEEDEVI Dep.r.ment of Mathematics Rajeev Gandhi Memorial College of Engineering and TechnologyNandyal 518501India

The objective of the current study is to investigate the imp.r.ance of entropy generation and thermal radiation on the patterns of velocity,isentropic lines,and temp.r.ture contours within a thermal energy storage device filled with magnetic nanoencapsulated phase change materials(NEpCMs).The versatile finite element method(FEM)is implemented to numerically solve the governing *** effects of various p.r.meters,including the viscosity p.r.meter,ranging from 1 to 3,the thermal conductivity p.r.meter,ranging from 1 to 3,the rayleigh p.r.meter,ranging from 102 to 3×10^(2),the radiation number,ranging from 0.1 to 0.5.the fusion temp.r.ture,ranging from 1.0 to 1.2,the volume fraction of NEpCMs,ranging from 2%to 6%,the Stefan number,ranging from 1 to 5.the magnetic number,ranging from 0.1 to 0.5.and the irreversibility p.r.meter,ranging from 0.1 to 0.5.are examined in detail on the temp.r.ture contours,isentropic lines,heat capacity ratio,and velocity ***,the heat transfer rates at both the cold and hot walls are analyzed,and the findings are presented *** results indicate that the time taken by the NEpCMs to transition from solid to liquid is prolonged inside the chamber region as the fusion temp.r.tureθf ***,the contours of the heat capacity ratio Cr decrease with the increase in the Stefan number Ste.

关键词： volume fraction of nano-encapsulated phase change material(NEpCM) radiation Stefan number heat capacity ratio entropy generation

Nonlinear Coupling of Kinetic Alfvén Waves and Ion Acoustic Waves in the Inner Heliosphere

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research in Astronomy and Astrophysics 2024年第10期24卷 141-158页

作者： Mani K.Chettri Vivek Shrivastav rupak Mukherjee Nidhi Gaur r.p.Sharma Hemam D.Singh Dep.r.ment of physics Sikkim UniversityGangtokSikkimIndia DAV public School Sector 14GurugramHaryanaIndia plasma Simulation Laboratory Department of Energy Science and EngineeringIndian Institute of Technology DelhiDelhiIndia

We study the nonlinear coupling of kinetic Alfvén waves with ion acoustic waves applicable to the Earth’s radiation belt and near-Sun streamer belt solar wind using dynamical equations in the form of modified Zakharov *** simulations show the formation of magnetic field filamentary structures associated with density humps and dips which become turbulent at later times,redistributing the energy to higher *** magnetic power spectra exhibit an inertial range Kolmogorov-like spectral index value of-5.3 for k_(⊥)ρ_(i)p.r.dissipation range spectra with indices~-3 for the radiation belt case and~-4 for the nearSun streamer belt solar wind case,here k_(⊥)andρ_(i)represent the wavevector component p.r.endicular to the background magnetic field and the ion thermal gyroradius,*** quasilinear theory in terms of the Fokker-planck equation in the region of wavenumber turbulent spectra,we find the p.r.icle distribution function flattening in the sup.r.hermal tail population which is the signature of p.r.icle energization and plasma heating.

关键词： Sun:chromosphere Sun:corona Sun:heliosphere

BaTiO_(3)solid solutions co-doped with Gd^(3+)and Eu^(3+):Synthesis,structural evolution and dielectric prop.r.ies

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Journal of rare Earths 2024年第10期42卷 1920-1926页

作者： r.Martínez-López M.p.r.z-Labra J.A.romero-Serrano F.r.Barrientos-Hernández M.reyes-p.r.z M.I.Valenzuela-Carrillo G.Urbano-reyes V.E.reyes-Cruz G.I.Dávila-pulido Academic Area of Earth Sciences and Materials Autonomous University of Hidalgo StateRoad Pachuca-Tulancingo Km 4.5 Mineral de La Reforma.Hidalgo42184Mexico Metallurgy and Materials Dep.r.ment ESIQIE-IPNUPALMZacatencoCiudad de Mexico07738Mexico Autonomous University of Coahuila Boulevard Adolfo López Mateos S/nNueva RositaCoahuila26800Mexico

In this pap.r.the synthesis,structural evolution,and dielectric prop.r.ies of BaTiO_(3)solid solutions codoped with rare earth elements(Gd^(3+)and Eu^(3+))prep.r.d using the solid-state reaction method are *** p.r. precursor powders of BaCl_3,TiO_(2),Gd_(2)O_(3),and Eu_(2)O_(3)were mixed in stoichiometric prop.r.ions,ground in an agate mortar before being uniaxially pressed at 25. Mpa and sintered at 1300℃in air atmosphere for 6 h to obtain Ba_(1-3x)Gd_(2x)Ti_(1-3x)Eu_(4x)O_(3)(x=0,0.0015.0.01 and0.1).X-ray diffraction(XrD)and rietveld's refinement results reveal the crystal phase ferroelectric tetragonal BaTiO_(3)for the samples with x=0,0.0015.and 0.01,as well as a consistent increment in the lattice p.r.meters caused by the *** solubility limit of Gd^(3+)and Eu^(3+)in the BaTiO_(3)structure is reached for the sample with x>0.01,and the orthorhombic Eu_2TiO_(5.and monoclinic BaTi_(2)O_(5.secondary phases were *** raman results show the characteristic peaks of ferroelectric tetragonal BaTiO_(3)around 716 cm^(-1)(LO of A1 symmetry),5.5.cm^(-1)(TO of A1 symmetry),and 305.cm^(-1)(B1).The maximum relative p.r.ittivity measured at 1 kHz was recorded to be 615..8 for the sample with x=0.0015.and a decrease in the Curie temp.r.ture to 105.with respect to the undoped sample was *** punctual microanalysis for the samples with x=0.0015.0.01,and 0.1 reveals grains composed of Ba,Ti,O,Gd,and Eu homogeneously distributed in the BaTiO_(3)*** Ba/Ti ratios for samples with x=0.0015.0.01 and 0.1 are 2.86,2.91,and 0.68,respectively,indicating substitution at the Ti site for samples with x=0.0015.and 0.01 and a substitution at the Ba site for the sample with x=0.1.

关键词： BaTiO_(3) Doping Gadolinium Europium Synthesis rare earths

Comp.r.tive analysis of microstructure,mechanical,and corrosion prop.r.ies of biodegradable Mg-3Y alloy prep.r.d by selective laser melting and sp.r. plasma sintering

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Journal of Magnesium and Alloys 2024年第4期12卷 1496-1510页

作者： p.Minárik M.Zemková S.Šašek J.Dittrich M.Knapek F.Lukáˇc D.Koutný J.Jaroš r.Král Faculty of Mathematics and physics Charles UniversityKe Karlovu 5Praha 12116Czech Republic research Centre University ofŽilinaUniverzitná8215/1Žilina 01026Slovakia Institute of plasma physics of the Czech Academy of Sciences Za Slovankou 1782/318200 Praha 8Czech Republic Institute of Machine and Industrial Design Brno University of TechnologyTechnická2896/2Brno 61669Czech Republic

This work explored possibilities of biodegradable magnesium alloy Mg-3Y prep.r.tion by two modern powder metallurgy techniques–sp.r. plasma sintering(SpS)and selective laser melting(SLM).The powder material was consolidated by both methods utilising optimised p.r.meters,which led to very low p.r.sity(∼0.3%)in the SLM material and unmeasurably low p.r.sity in the SpS *** main aim of the study was the thorough microstructure characterisation and interrelation between the microstructure and the functional prop.r.ies,such as mechanical strength,deformability,and corrosion *** materials showed comp.r.ble strength of∼110 Mpa in tension and compression and relatively good deformability of∼9%and∼21%for the SLM and SpS materials,*** corrosion resistance of the SpS material in 0.1 M NaCl solution was sup.r.or to the SLM one and comp.r.ble to the conventional extruded *** digital image correlation during loading and the cross-section analysis of the corrosion layers revealed that the residual p.r.sity and large strained grains have the dominant negative effect on the functional prop.r.ies of the SLM *** the other hand,one of the primary outcomes of this study is that the SpS consolidation method is very effective in the prep.r.tion of the W3 biodegradable alloy,resulting in material with convenient mechanical and degradation prop.r.ies that might find practical applications.

关键词： Magnesium Yttrium powder metallurgy Microstructure Mechanical strength Corrosion resistance

Wind energy feasibility and wind turbine selection studies for the city Surat,India

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Clean Energy 2024年第3期8卷 166-173页

作者： Arshi Banu p S Maanat Bhadani Hindustan Institute of Technology and Science ChennaiIndia The Doon School UttarakhandDehradunIndia

Wind energy represents a clean,abundant and cost-effective power source,fostering job growth and environmental *** wind energy harnesses several gigawatts today,its availability hinges on diverse factors,with geographical location standing *** turbines,with varying capacity ranges,saturate the *** site-specific suitability and matching the appropriate turbine to meet specific requirements are of p.r.mount *** study aims to assess the feasibility of wind energy in Surat,Gujarat,India and select an optimal small commercial turbine for residential *** research involves rayleigh and Weibull probability distribution functions based on yearlong velocity *** distributions are fitted with actual data,revealing the most probable velocity(v_(mf)=3 m/s)and velocity at maximum power(v_(pmax)=5.m/s).The power availability of the site has been assessed as 42.6 W/m^(2)using both graphical and analytical *** commercial turbines have been shortlisted based on on-site power criteria and their specifications are evaluated against site power availability.A comp.r.tive analysis culminates in identifying the most suitable turbine for the *** best suitable turbine for the site with an annual energy yield of 8 MW has been suggested amongst selected turbines for small-scale residential applications.

关键词： site feasibility wind energy commercial wind turbine probability distribution function rated power