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Luminescence properties of near-UV excitable yellow-orange light emitting warm CaSrAl_2SiO_7:Sm^(3+) phosphors

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Journal of Rare Earths 2019年第4期37卷 365-373页

作者： Shweta Sharma Nameeta Brahme d.p.Bisen pradeep dewangan School of Studies in physics and Astrophysics Pt.Ravishankar Shukla University Center for Nanoscience and Nanotechnology Pt.Ravishankar Shukla University

Single-phase CaSrAl_2 SiO_7:Sm^(3+) phosphors were synthesized by traditional high temperature solid state reaction method. Formation of samples and phase analysis were confirmed by X-ray diffraction technique. Morphology was done by field emission scanning electron microscopy and elemental compositions were confirmed by energy dispersive X-ray analysis. present phosphors have tetragonal crystallography with space group p42_1 m. Average crystallite size was calculated by using Scherrer and Williamson-Hall method. photoluminescence study of CaSrAl_2 SiO_7:Sm^(3+) phosphor was *** different excitation wavelengths, pL spectra consist of four emission bands at 564, 570, 601 and650 nm. The emission bands located at 564 and 570 nm are associated with the transition ~4 G_(5/2)→~6 H_(5/2)while emission bands at 601 and 650 nm are due to ~4 G_(5/2)→~6 H_(7/2) and ~4 G_(5/2)→~6 H_(9/2),*** emission was obtained when phosphor was excited under 404 nm wavelength. Non-radiative energy transfer process involved in concentration quenching, was also discussed. CIE coordinate is found in yellow-orange region, hence CaSrAl_2SiO_7:Sm^(3+) phosphors emit yellow-orange light when efficiently excited by near UV(～400 nm) LEd chip. Color purity and CCT of the phosphor were determined; CCT suggests that present phosphor is a good candidate as a warm yellow-orange color emitting phosphor. Effect of different heating rates and different UV exposure time on the TL glow curve of the phosphor was investigated. Activation energies and kinetic parameters for different traps were calculated by using peak shape method. TL emission spectrum was also recorded. present article explains all the possible mechanisms associated with luminescence process in CaSrAl_2 SiO_7:Sm^(3+) phosphors.

关键词： Thermoluminescence photoluminescence Aluminosilicate Yellow-orange emitting phosphor Samarium CaSrAl2SiO7:Sm3+

Effects of variable viscosity and temperature modulation on linear Rayleigh-Bénard convection in Newtonian dielectric liquid

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Applied Mathematics and Mechanics(English Edition) 2019年第11期40卷 1601-1614页

作者： p.G.SIddHESHWAR d.UMA S.BHAVYA department of Mathematics Bangalore UniversityBengaluru 560056India department of Computer Science and Engineering PES UniversityBengaluru 560085India department of Mathematics Atria Institute of TechnologyBengaluru 560024India

The linear Rayleigh-Bénard electro-convective stability of the Newtonian dielectric liquid is determined theoretically subject to the temperature modulation with time.A perturbation method is used to compute the critical Rayleigh number and the wave *** critical Rayleigh number is calculated as a function of the frequency of modulation,the temperature-dependent variable viscosity,the electric field dependent variable viscosity,the prandtl number,and the electric Rayleigh *** effects of all three cases of modulations are established to delay or advance the onset of the convection *** addition,how the effect of variable viscosity controls the onset of convection is studied.

关键词： dielectric liquid temperature dependent variable viscosity electric field dependent variable viscosity electric Rayleigh number temperature modulation

Experimental Investigation of Separation and Transition processes on a High-Lift Low-pressure Turbine profile Under Steady and Unsteady Inflow at Low Reynolds Number

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Journal of Thermal Science 2010年第1期19卷 26-33页

作者： Satta F Simoni d Ubaldi M Zunino p Bertini F dIMSET-Università di Genova Via Montallegro 1I-16145 GenovaItaly Avio R&d V.I Maggio99 I-10040 Rivalta(TO)-Italy

The effects induced by the presence of incoming wakes on the boundary layer developing over a high-lift low-pressure turbine profile have been investigated in a linear cascade at *** tested Reynolds number is 70000,typical of the cruise operating *** results of the investigations performed under steady and unsteady inflow conditions are *** unsteady investigations have been performed at the reduced frequency of f+=0.62,representative of the real engine operating *** aerodynamic loadings as well as boundary layer velocity profiles have been measured to survey the separation and transition *** analysis has been also performed to better understand the phenomena associated with the transition process under steady *** the unsteady case,a phase-locked ensemble averaging technique has been employed to reconstruct the time-resolved boundary layer velocity distributions from the hot-wire instantaneous signal *** ensemble-averaging technique allowed a detailed analysis of the effects induced by incoming wakes-boundary layer interaction in separation ***-resolved results are presented in terms of mean velocity and unresolved unsteadiness time-space plots.

关键词： boundary layer separation boundary layer transition wake-boundary layer interaction high-liftprofile low-pressure turbine

Ruppert's delaunay Triangulation Refinement Scheme for Optimal RSUs placement in Vehicle to Infrastructure Communication Network

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China Communications 2023年第7期20卷 303-320页

作者： Selvakumari p Chinnasamy A Sree Rathna Lakshmi NVS Sheela d department of Computer Science and Engineering Tagore Engineering CollegeChennai 600048India department of data Science and Business Systems School of ComputingSRMIST kattankulathur CampusChennai 603203India department of Electronics and Communication Engineering Department of ECE at Agni College of TechnologyChennai 603103India department of Electronics and Communication Engineering Saveetha School of Engineering SIMATSChennai 600124India

Road Side Units(RSUs)are the essential component of vehicular communication for the objective of improving safety and mobility in the road *** are generally deployed at the roadside and more specifically at the intersections in order to collect traffic information from the vehicles and disseminate alarms and messages in emergency situations to the neighborhood vehicles cooperating with the ***,the development of a predominant RSUs placement algorithm for ensuring competent communication in VANETs is a challenging issue due to the hindrance of obstacles like water bodies,trees and *** this paper,Ruppert’s delaunay Triangulation Refinement Scheme(RdTRS)for optimal RSUs placement is proposed for accurately estimating the optimal number of RSUs that has the possibility of enhancing the area of coverage during data *** RdTRS is proposed by considering the maximum number of factors such as global coverage,intersection popularity,vehicle density and obstacles present in the map for optimal RSUs placement,which is considered as the core improvement over the existing RSUs optimal placement *** is contributed for deploying requisite RSUs with essential transmission range for maximal coverage in the convex map such that each position of the map could be effectively covered by at least one RSU in the presence of *** simulation experiments of the proposed RdTRS are conducted with complex road traffic *** results of this proposed RdTRS confirmed its predominance in reducing the end-to-end delay by 21.32%,packet loss by 9.38%with improved packet delivery rate of 10.68%,compared to the benchmarked schemes.

关键词： road side units(RSUs) ruppert’s delau-nay triangulation refinement area of global coverage optimal RSUs placement

Unlocking hypoglycemia–associated brain microvascular dysfunction:critical insights from proteomic analysis

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Neural Regeneration Research 2025年第6期20卷 1707-1708页

作者： Siva S.V.p.Sakamuri Anil Sakamuri department of Chemistry Auburn University at MontgomeryMontgomeryALUSA Vascular Biology Center and department of Medicine Medical College of Georgia at Augusta UniversityAugustaGAUSA

Hypoglycemia-a critical complication linked to worsened brain function in diabetic subjects:Hypoglycemia is characterized by a decline in circulatory glucose levels below sta nda rd physiological *** hypoglycemia,classified as level 1 hypoglycemia,is defined by blood glucose levels below 70 mg/dL and can be effectively addressed through carbohydrate *** hypoglycemia,denoted by blood glucose levels less than 54 mg/dL,poses a life-threatening risk if left *** with type 1 and type 2 diabetes undergoing insulin treatment are particularly susceptible to hypoglycemia due to impaired counterregulatory mechanisms.

关键词： impaired intake critical

Interference with the formation of the epididymal microenvironment——a new strategy for male contraception?

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Asian Journal of Andrology 2000年第1期2卷 39-45页

作者： X.d.Gong G.p.H.Leung B.L.Y.Cheuk p.Y.d.Wong department of phsiology The Chinese University of Hong Kong Shatin N. T. Hong Kong ChinaDepartment of Phsiology The Chinese University of Hong Kong Shatin N. T. Hong Kong ChinaDepartment of Phsiology The Chinese University of Hong Kong Shatin N. T. Hong Kong ChinaDepartment of Phsiology The Chinese University of Hong Kong Shatin N. T. Hong Kong China

The cystic fibrosis transmembrane conductance regulator (CFIR) or the small conductance cAMp-activated chlo-ride channel encoded by the CFTR gene has been shown to play an important role in the formation of the epididymalfluid microenvironment. Recent work in our laboratory has shown that this protein is also expressed by developing germcells indicating a role of this protein in spermatogenesis. In view of the fact that the CFTR gene has a far reaching andwidespread effect on human reproduction, understanding the role of CFTR in the male reproductive tissues and its inter-vention by pharmacological agents can open a new avenue of research into the development of novel male contracep-tives. (Asian J Androl 2000; 2: 39 - 45 )

关键词： epididymis cyclooxygenase contraception cystic fibrosis transmembrane conductance regulator

Study of bond strength between various grade of Ordinary portland Cement(OpC)and portland pozzolane Cement(ppC)mixes and different diameter of TMT bars by using pullout test

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Frontiers of Structural and Civil Engineering 2013年第1期7卷 39-45页

作者： A d pOFALE S p WANJARI department of Civil Engineering Visvesvarya National Institute of TechnologyNagpur 440010India

Since last two decades,the portland pozzolane Cement(ppC)is extensively used in structural ***,till to date,a few literature is available on bond strength of concrete using ppC *** are many literatures available on bond strength of concrete mixes using Ordinary portland Cement(OpC).Hence,a comparative study was conducted on bond strength between OpC and ppC *** the present investigation,total 24 samples consisting of M20,M35 and M50 grades of concrete and 16 and 25 mm diameter of TMT bar were tested for 7 and 28 *** pullout bond test was conducted on each specimen as per IS:2770-1967/1997[1]and the results were observed at 0.25 mm slip at loaded end called as critical bond stress and at maximum bond load called as maximum bond *** was observed that the critical bond strength of ppC mixes is 10%higher than OpC ***,marginal improvement was noticed in maximum bond strength of ppC ***,based on these findings,it could be concluded that development length for ppC mixes could be reduced by 10%as compared with same grade of OpC mixes.

关键词： bond strength portland pozzolane Cement(ppC)concrete Ordinary portland Cement(OpC)concrete bond between concrete and steel pullout test development length

Sensitivity analysis of an HgCdTe based photovoltaic receiver for long-wavelength free space optical communication systems

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Optoelectronics Letters 2009年第1期5卷 21-25页

作者： A.d.d.dwivedi p.Chakrabarti Centre for Research in Microelectronics Department of Electronics EngineeringInstitute of TechnologyBanaras Hindu University

We examine theoretically the performance of an Hg0.77Cd0.23Te based p-n photodetector/HFET optical receiver due to its possible application at 10.6 μm free space optical communication system at high bit rate.A rigorous noise model of the receiver has been developed for this *** calculate the total noise and sensitivity of the *** front-end of the receiver exhibits a sensitivity of -45 dBm at a bit rate of 1 Gb/s and -30 dBm at a bit rate of 10 Gb/s,and the total mean-square noise curren t〈i2n〉=5×10-15 A2 at a bit rate of 1 Gb/s an d〈i2n〉 =10-12 A2 at a bit rate of 10 Gb/s,and a 3-dB bandwidth of 10 GHz.

关键词： Hg HFET Sensitivity analysis of an HgCdTe based photovoltaic receiver for long-wavelength free space optical communication systems free

Effect of silica source on photocatalytic properties of Bi_(2)O_(3)/Bi_(2)SiO_(5) heterostructure

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Journal of Bioresources and Bioproducts 2023年第2期8卷 176-186页

作者： O.d.Arefieva M.S.Vasilyeva L.A.Zemnukhova d.p.Opra d.A.Nikolaeva V.V.Tkachev d.H.Shlyk Far Eastern Federal University Vladivostok 690922Russian Federation Institute of Chemistry Far-Eastern BranchRussian Academy of SciencesVladivostok 690922Russian Federation

The Bi_(2)O_(3)/Bi_(2)SiO_(5) heterostructures were obtained with various samples of silica as a precursor:on the basis of biogenic silica isolated from rice husk and rice straw and the silica of mineral ori-gin.A mixture of Bi(NO_(3))_(3) and SiO_(2) with a mass content of 15%was used for synthesizing all the *** transform infrared(FT-IR)spectroscopy,scanning electron microscope(SEM),X-ray phase,X-ray fluorescence,and ultraviolet-visible diffused reflectance spectroscopy(UV-vis dRS)were used to systematically characterize as-obtained *** of methyl orange in neutral aqueous solutions(pH=6.8)under UV irradiation was studied to evaluate their photocatalytic ***,bandgaps,the value of the zero charge point,and photo-catalytic activity of the samples depended on the characteristics of the original *** degree of methyl orange degradation reached the maximum values(81%−85%)for samples based on precipitated silica from rice husks,straw,and the minimum value(16%)for a composite with thermal silica from rice *** based on thermal silica from rice husks and reagents from mineral raw materials did not statistically differ from each other in the degree of methyl orange degradation(67%−74%).

关键词： Biogenic silica Heterostructures photocatalysis Rice husk Rice straw