检索结果-南通市图书馆

维普期刊数据库

Exploring one material for dual applications:A red-emitting Mg2GeO4:Eu3+ nanophosphor for future generation energy efficient WLEDs and dosimetric applications

在线全文

学校读者我要写书评

暂无评论

Journal of Rare Earths 2024年第10期42卷 1835-1845页

作者： Akshay Arjun G.p.Darshan S.C.Sharma h.Nagabhushana D.V.Sunitha h.B.premkumar Department of physics Faculty of Mathematical and Physical SciencesM.S.Ramaiah University of Applied Sciences Jain University C.N.R.Rao Centre for Advanced Materials Tumkur University School of Applied Sciences (physics) REVA University

The envisaged design and developme nt of individual mate rials to excavate a broader spectrum of desired properties and offer multiple applications are highly *** this in mind,a series of forsterite-structured Mg2GeO4:Eu3+（1 mol%-9 mol%） nanophosphors was synthesized via a solution combustion method using oxalyl dihydrazide as a *** X-ray diffraction patterns confirm the orthorhombic crystal system with a puma space *** results clearly show irregularly shaped cluster-like structures with aggregation of the *** diffuse reflectance spectra,the optical energy band gap of the Mg2GeO4:Eu3+（1 mol%-9 mol%） nanophosphors was estimated and obtained to be～4.12-4.32 *** photoluminescence emission spectra exhibit intense peaks at ～579,589,610,661,and 707 nm,which are due to characteristic5D0→7F0,5D0→7F1,5Do→7F2,5D0→7F3and5D0→7F4transitions of Eu3+ions,*** Commission International de L'Eclairage color coordinates are gradually tuned from pale red（0.5980,0.4012） to a pure red（0.6385,0.3611） *** glow peaks showcase excellent super-linear response at low doses of γ-irradiations,indicating that the prepared phosphor can be used in thermoluminescent personal dosimetry which is a biological tissue *** aforementioned results demonstrate that the prepared Mg2GeO4:Eu3+（1 mol%-9 mol%） nanophosphors are considered an excellent candidate for dual applications,i.e.,red component in future generation white-light-emitting diodes（WLEDs） and personal dosimetric applications.

关键词： Dosimetry Nanophosphors photoluminescence photometric properties Rare earths Thermoluminescence

Exact solutions for magnetohydrodynamic nanofluids flow and heat transfer over a permeable axisymmetric radially stretching/shrinking sheet

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Chinese physics B 2024年第2期33卷 108-114页

作者： U.S.Mahabaleshwar G.p.Vanitha L.M.pérez Emad h.Aly I.pop Department of Studies in Mathematics Davangere UniversityShivagangothriDavangereIndia Departamento de F´ısica FACIUniversidad de Tarapac´aCasilla 7DAricaChile Department of Mathematics Faculty of EducationAin Shams UniversityRoxyCairoEgypt Department of Mathematics Babes-Bolyai University400084 Cluj-NapocaRomania

We report on the magnetohydrodynamic impact on the axisymmetric flow of Al_(2)O_(3)/Cu nanoparticles suspended in h_(2)O past a stretched/shrinked *** the use of partial differential equations and the corresponding thermophysical characteristics of nanoparticles,the physical flow process is *** resultant nonlinear system of partial differential equations is converted into a system of ordinary differential equations using the suitable similarity *** transformed differential equations are solved *** of the magnetic parameter,solid volume fraction and stretching/shrinking parameter on momentum and temperature distribution have been analyzed and interpreted *** skin friction and Nusselt number were also *** addition,existence of dual solution was deduced for the shrinking sheet and unique solution for the stretching ***,Al_(2)O_(3)/h_(2)O nanofluid flow has better thermal conductivity on comparing with Cu/h_(2)O ***,it was found that the first solutions of the stream are stable and physically realizable,whereas those of the second ones are unstable.

关键词： magnetohydrodynamic nanofluid stretching/shrinking sheet axisymmetric flow analytical solution suction/injection

维普期刊数据库

The potential of glutamine supplementation in reduced-crude protein diets for chicken-meat production

在线全文

学校读者我要写书评

暂无评论

Animal Nutrition 2024年第3期18卷 49-56页

作者： peter h.Selle Shemil p.Macelline Mehdi Toghyani Sonia Yun Liu poultry Research Foundation within the University of Sydney CamdenNSW 2570Australia Sydney School of Veterinary Science The University of SydneyCamdenNSW 2570Australia School of Life and Environmental Sciences Faculty of ScienceThe University of SydneyCamdenNSW 2570Australia

This review explores the potential of including glutamine,a so-called non-essential amino acid,in the formulation of reduced-crude protein(Cp)diets for broiler *** is a precedent for benefits when including glycine and serine in reduced-Cp *** this is due to decreases in non-essential amino acid concentrations in reduced-Cp diets—an unavoidable consequence of reducing Cp without amino acid *** situation for glutamine is complicated because analysed dietary concentrations are very rarely provided as standard assays do not differentiate between glutamine and glutamate and are reported on a combined basis as glutamic *** dietary requirement for glutamic acid is approximately 36.3 g/kg but it is increasingly unlikely that this requirement will be met as dietary Cp levels are progressively *** is an abundant and versatile amino acid and constitutes 50.5 mg/g of whole-body chicken protein and is the dominant free amino acid in systemic plasma where it has been shown to provide 22.6%(139.9 of 620.3μg/mL)of the total in birds offered 215 g/kg Cp,wheat-based *** addition to dietary intakes,glutamine biosynthesis is derived mainly from the condensation of glutamate and ammonia(Nh3)catalysed by glutamine synthetase,a reaction that is pivotal to Nh3 *** and Nh3 are converted to glutamine by phosphate-dependent glutaminase in the reciprocal reaction;thus,glutamine and glutamate are interchangeable amino ***,the rate of glutamine biosynthesis may not be adequate in rapidly growing broiler chickens and exogenous and endogenous glutamine levels are probably insufficient in birds offered reduced-Cp *** many functional roles of glutamine,including Nh3 detoxification and maintenance of acid-base homeostasis,then become *** feeding studies were identified where dietary glutamine supplementation,usually 10 g/kg,was evaluated in birds kept under thermoneutral ***

关键词： Broiler chicken Glutamate Glutamic acid Glutamine

Fast efficient photon deceleration in plasmas by using two laser pulses at different frequencies

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Matter and Radiation at Extremes 2024年第3期9卷 11-18页

作者： Y.X.Wang X.L.Zhu S.M.Weng p.Li X.F.Li h.Ai h.R.pan Z.M.Sheng Key Laboratory for Laser plasmas(moe) School of Physics and AstronomyShanghai Jiao Tong UniversityShanghai 200240China Collaborative Innovation Center of IFSA Shanghai Jiao Tong UniversityShanghai 200240China Research Center of Laser Fusion of China Academy of Engineering physics MianyangSichuan 621900China State key Laboratory of high Field Laser physics Shanghai Institute of Optics and Fine MechanicsChinese Academy of SciencesShanghai 201800China Tsung-dao Lee Institute Shanghai Jiao Tong UniversityShanghai 200240China

The generation of ultrashort high-power light sources in the mid-infrared(mid-IR)to terahertz(Thz)range is of interest for applications in a number of fields,from fundamental research to biology and *** conventional laser technology,photon deceleration in plasma wakes provides an alternative approach to the generation of ultrashort mid-IR or Thz ***,we present a photon deceleration scheme for the efficient generation of ultrashort mid-IR or Thz pulses by using an intense driver laser pulse with a relatively short wavelength and a signal laser pulse with a relatively long *** signal pulse trails the driver pulse with an appropriate time delay such that it sits at the front of the second wake bubble that is driven by the driver *** to its relatively long wavelength,the signal pulse will be subjected to a large gradient of the refractive index in the plasma wake ***,the photon deceleration in the plasma wake becomes faster and more efficient for signal pulses with longer *** greatly enhances the capacity and efficiency of photon deceleration in the generation of ultrashort high-power light sources in the long-wavelength IR and Thz spectral ranges.

关键词： laser ultrashort photon

Effect of radiative loss mechanisms on FIR thermometric parameters of Nd^(3+)-doped lithium tellurite glasses

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Rare Earths 2024年第7期42卷 1250-1257,I0002页

作者： C.Y.Morassuti A.p.L Silva L.A.O.Nunes S.M.Lima L.h.C.Andrade Optical and photothermal Spectroscopy Group(GEOF) Center for Studies in Natural Resources(CERNA)State University of Mato Grosso do Sul(UEMS)C.P.351DouradosMSBrazil Renato Archer Information Technology Center Dom Pedro I Highway(SP-65)Km 1436-Chácaras Campos dos AmaraisCampinasSPBrazil Institute of physics of São Carlos University of São PauloSão CarlosSPBrazil

Nd^(3+)-doped tellurite glasses are promising materials for thermometers based on the fluorescence intensity ratio(FIR)***,at high Nd^(3+)concentrations,energy transfer(ET)processes such as optical reabsorption and cross-relaxation can affect the Nd^(3+)emission,which has been little explored in the ***,the present work investigated the use of Nd^(3+)-doped tellurite glass(samples doped with Nd^(3+)at 0.2 mol%,0.5 mol%,2.0 mol%,and 4.0 mol%)in fluorescence thermometers,in the temperature range from 299 to 371 *** results indicate a strong dependence of the FIR parameters on the Nd^(3+)concentration,due to changes in the emission band profiles caused by optical reabsorption of the Nd^(3+)emissions and cross-relaxation processes.A decrease of the relative sensitivity of the ratio^(4)F_(5/2)→^(4)I_(9/2)/^(4)F_(3/2)→^(4)I_(9/2)is observed for samples doped with higher amounts of Nd^(3+).The maximum relative sensitivity at 299 K is 3.00%/K,which is the highest value among the reported Nd^(3+)ions.

关键词： Nd^(3+)-doped tellurite glass Fluorescence intensity ratio Optical thermometry Judd-Ofelt Rare earths

维普期刊数据库

Efficient guiding and focusing of intense laser pulse using periodic thin slits

在线全文

学校读者我要写书评

暂无评论

Matter and Radiation at Extremes 2024年第4期9卷 29-39页

作者： L.Xu T.W.huang K.Jiang C.N.Wu h.peng p.C.hen R.Li h.B.Zhuo C.T.Zhou Shenzhen Key Laboratory of Ultraintense Laser and Advanced Material Technology Center for Intense Laser ApplicationTechnologyand College of Engineering PhysicsShenzhen Technology UniversityShenzhen 518118People’s Republic of China

Slits have been widely used in laser-plasma interactions as plasma optical components for generating high-harmonic light and controlling laser-driven particle ***,we propose and demonstrate that periodic thin slits can be regarded as a new breed of optical elements for efficient focusing and guiding of intense laser *** fundamental physics of intense laser interaction with thin slits is studied,and it is revealed that relativistic effects can lead to enhanced laser focusing far beyond the pure diffractive focusing *** addition,the interaction of an intense laser pulse with periodic thin slits makes it feasible to achieve multifold enhancement in both laser intensity and energy transfer efficiency compared with conventional *** results provide a novel method for manipulating ultra-intense laser pulses and should be of interest for many laser-based applications.

关键词： laser pulse intense

hydromechanical characterization of gas transport amidst uncertainty for underground nuclear explosion detection

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Rock Mechanics and Geotechnical Engineering 2024年第6期16卷 2019-2032页

作者： Wenfeng Li Chelsea W.Neil J William Carey Meng Meng Luke p.Frash philip h.Stauffer Earth and Environmental Sciences Los Alamos National LaboratoryLos AlamosNM87544USA Department of Mineral Engineering New Mexico TechSocorroNM87801USA

Given the challenge of definitively discriminating between chemical and nuclear explosions using seismic methods alone,surface detection of signature noble gas radioisotopes is considered a positive identification of underground nuclear explosions(UNEs).however,the migration of signature radionuclide gases between the nuclear cavity and surface is not well understood because complex processes are involved,including the generation of complex fracture networks,reactivation of natural fractures and faults,and thermo-hydro-mechanical-chemical(ThMC)coupling of radionuclide gas transport in the *** this study,we provide an experimental investigation of hydro-mechanical(hM)coupling among gas flow,stress states,rock deformation,and rock damage using a unique multi-physics triaxial direct shear rock testing *** testing system also features redundant gas pressure and flow rate measurements,well suited for parameter uncertainty *** porous tuff and tight granite samples that are relevant to historic UNE tests,we measured the Biot effective stress coefficient,rock matrix gas permeability,and fracture gas permeability at a range of pore pressure and stress *** Biot effective stress coefficient varies from 0.69 to 1 for the tuff,whose porosity averages 35.3%±0.7%,while this coefficient varies from 0.51 to 0.78 for the tight granite(porosityperhaps an underestimate).Matrix gas permeability is strongly correlated to effective stress for the granite,but not for the porous *** experiments reveal the following key engineering implications on transport of radionuclide gases post a UNE event:(1)The porous tuff shows apparent fracture dilation or compression upon stress changes,which does not necessarily change the gas permeability;(2)The granite fracture permeability shows strong stress sensitivity and is positively related to shear displacement;and(3)hydromechanical coupling among stress states,rock damage,and gas flow appears to be

关键词： Underground nuclear explosion uncertainty quantification Radionuclide transport Biot effective stress coefficient Fracture permeability Matrix permeability

Role of marine natural products in the development of antiviral agents against SARS‑CoV‑2:potential and prospects

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Marine Life Science & Technology 2024年第2期6卷 280-297页

作者： D.p.Nagahawatta N.M.Liyanage Thilina U.Jayawardena h.h.A.C.K.Jayawardhana Seong‑hun Jeong hyung‑Jun Kwon You‑Jin Jeon Department of Marine Life Sciences Jeju National UniversityJeju 690-756Republic of Korea Department of Chemistry Biochemistry and PhysicsUniversitédu QuébecàTrois-RivièresTrois-RivièresQC G8Z 4M3Canada Marine Science Institute Jeju National UniversityJeju 63333Republic of Korea Functional Biomaterial Research Center Korea Research Institute of Bioscience and BiotechnologyJeongeup-siRepublic of Korea

A novel coronavirus,known as severe acute respiratory syndrome coronavirus 2(SARS-CoV-2),has surfaced and caused global concern owing to its ***-CoV-2 is the causative agent of coronavirus disease 2019;however,it was only discovered at the end of the year and was considered a pandemic by the World health ***,the develop-ment of novel potent inhibitors against SARS-CoV-2 and future outbreaks is urgently *** naturally occurring bioactive substances have been studied in the clinical setting for diverse *** intricate infection and replication mechanism of SARS-CoV-2 offers diverse therapeutic drug targets for developing antiviral medicines by employing natural products that are safer than synthetic *** natural products(MNps)have received increased attention in the development of novel drugs owing to their high diversity and ***,this review article investigates the infection and replication mechanisms,including the function of the SARS-CoV-2 genome and ***,we highlighted anti-SARS-CoV-2 therapeutic intervention efforts utilizing MNps and predicted SARS-CoV-2 inhibitor design.

关键词： SARS-CoV-2 Marine natural products Drug targets Inhibitors

Electron kinetic effects in back-stimulated Raman scattering bursts driven by broadband laser pulses

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Matter and Radiation at Extremes 2024年第4期9卷 54-67页

作者： Q.K.Liu L.Deng Q.Wang X.Zhang F.Q.Meng Y.p.Wang Y.Q.Gao h.B.Cai S.p.Zhu Graduate School China Academy of Engineering PhysicsBeijing 100088China Institute of Applied physics and Computational Mathematics Beijing 100094China School of Nuclear Science and Technology University of Science and Technology of ChinaHefei 230026China Shanghai Institute of Laser plasma Shanghai 201800China hEDpS Center for Applied Physics and TechnologyPeking UniversityBeijing 100871China School of physics Zhejiang UniversityHangzhou 310027China

We examine electron kinetic effects in broadband-laser-driven back-stimulated Raman scattering(BSRS)bursts using particle-in-cell *** bursts occur during the nonlinear stage,causing reflectivity spikes and generating large numbers of hot ***-duration simulations are performed to observe burst events,and a simplified model is developed to eliminate the interference of the broadband laser’s random intensity *** the simplified model,we isolate and characterize the spectrum of electron plasma *** spectrum changes from a sideband structure to a turbulence-like structure during the burst.A significant asymmetry in the spectrum is *** asymmetry is amplified and transferred to electron phase space by high-intensity broadband laser pulses,leading to violent vortex-merging and generation of hot *** proportion of hot electrons increases from 6.76%to 14.7%during a single violent burst *** demonstrate that kinetic effects profoundly influence the BSRS evolution driven by broadband lasers.

关键词： scattering kinetic simplified