检索结果-南通市图书馆

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

Recent research in mechanical properties of geopolymer-based ultrahigh-performance concrete:A review

在线全文

学校读者我要写书评

暂无评论

Defence Technology（防务技术） 2024年第2期32卷 67-88页

作者： g.Murali Division of Research&Innovation Uttaranchal UniversityDehradun 248007India

Due to the growing need for sustainable and ultra-high-strength construction materials,scientists have created an innovative ultra-high-performance concrete called geopolymer based ultra-highperformance concrete(gUHPC).Besides,in the last few decades,there have been a lot of explosions and ballistic attacks around the world,which have killed many civilians and fighters in border *** this context,this article reviews the fresh state and mechanical properties of ***,the ingredients of gUHPC and fresh properties such as setting time and flowability are briefly ***,the review of compressive strength,flexure strength,tensile strength and modulus of elasticity of fibrous ***,the blast and projectile impact resistance performance was ***,the microstructural characteristics were reviewed using the scanning electron microscope and X-ray Powder *** review outcome reveals that the mechanical properties were increased when 30%silica fume was added to a higher dose of steel fibre to improve the microstructure of *** is hypothesized that the brittleness of gUHPC was mitigated by adding 1.5%steel fibre reinforcement,which played a role in the decrease of contact explosion cratering and *** the need for cement in gUHPC was a key factor in the review,indicating a promising potential for lowering carbon ***,gUHPC research is still in its early stages,so more study is required before its full potential can be utilized.

关键词： Mechanical properties Blast Projectile impact Fibre geopolymer silica fume Alkaline activators

Interfacial stress engineering toward enhancement of ferroelectricity in Al doped HfO_(2)thin films

在线全文

学校读者我要写书评

暂无评论

Chinese Physics B 2024年第9期33卷 637-643页

作者： s X Chen M M Chen Y Liu D W Cao g J Chen Department of Microelectronics Jiangsu UniversityZhenjiang 212013China Department of Physics Jiangsu UniversityZhenjiang 212013China guangdong–Hong Kong–Macao Joint Laboratory for Intelligent Micro-Nano Optoelectronic Technology Foshan UniversityFoshan 528225China

Ferroelectric HfO_(2)has attracted much attention owing to its superior ferroelectricity at an ultra-thin thickness and good compatibility with si-based complementary metal-oxide-semiconductor(CMOs)***,the crystallization of polar orthorhombic phase(o-phase)HfO_(2)is less competitive,which greatly limits the ferroelectricity of the as-obtained ferroelectric HfO_(2)thin ***,the crystallization of o-phase HfO_(2)can be thermodynamically modulated via interfacial stress *** this paper,the growth of improved ferroelectric Al doped HfO_(2)(HfO_(2):Al)thin films on(111)-oriented si substrate has been *** analysis has suggested that nonpolar monoclinic HfO_(2):Al grown on(111)-oriented si substrate suffered from a strong compressive strain,which promoted the crystallization of(111)-oriented o-phase HfO_(2)in the as-grown HfO_(2):Al thin *** addition,the in-plane lattice of(111)-oriented si substrate matches well with that of(111)-oriented o-phase HfO_(2),which further thermally stabilizes the o-phase HfO_(2).Accordingly,an improved ferroelectricity with a remnant polarization(2P_(r))of 26.7C/cm^(2) has been *** results shown in this work provide a simple way toward the preparation of improved ferroelectric HfO_(2)thin films.

关键词： improved ferroelectricity interfacial stress engineering compressive strain HfO_(2)

Construction of 2D/2D Ti_(3)C_(2)T_(x)MXene/Cds heterojunction with photothermal effect for efficient photocatalytic hydrogen production

在线全文

学校读者我要写书评

暂无评论

Journal of Materials science & Technology 2024年第4期171卷 1-9页

作者： T.Y.Huang Z.Yang s.Y.Yang Z.H.Dai Y.J.Liu J.H.Liao g.Y.Zhong Z.J.Xie Y.P.Fang s.s.Zhang Key Laboratory for Biobased Materials and Energy of Ministry of Education Guangdong Laboratory for Lingnan Modern AgricultureCollege of Materials and EnergySouth China Agricultural UniversityGuangzhou 510643China school of Physics and Optoelectronics South China University of TechnologyGuangzhou 510640China school of Chemical Engineering and Energy Technology Guangdong Provincial Key Laboratory of Distributed Energy SystemsDongguan University of TechnologyDongguan 523808China

The insensitivity of semiconductors to visible and infrared light is a key constraint on the utilization of light energy in photocatalytic *** photocatalysts with full-spectrum absorption through surface engineering is an effective approach to fully harnessing light energy in semiconductor ***,a novel stable Ti_(3)C_(2)T_(x)MXene/Cds heterojunction catalyst is obtained by in-situ epitaxial growth of two-dimensional(2D)Cds nanosheets on 2D MXene interface via a solvothermal *** exceptional light absorption properties of MXene confer outstanding full-spectrum driven photocat-alytic hydrogen evolution capability upon the heterogeneous *** unique 2D/2D structure effectively mitigated the recombination of photogenerated carriers,enhancing the photocatalytic performance of the ***,the composite catalyst exhibits a significantly higher surface temperature of 80.4℃under visible light irradiation at an intensity of 0.1 W/cm^(2),which is 1.84 times higher than that of *** irradiation of visible and near infrared light,the composite catalyst with photothermal ef-fect demonstrates a remarkable hydrogen evolution rate of 65.4 mmol g^(-1)h^(-1),which is 7.2 times higher than that of Cds *** study introduces a novel approach for constructing full-spectrum absorption catalysts and expands the application of the photothermal effect in photocatalytic hydrogen evolution research.

关键词： Two-dimensional structure Heterostructure Photothermal effect Photocatalyst Hydrogen evolution

Towards an integrated risk analysis security framework according to a systematic analysis of existing proposals

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Frontiers of Computer science 2024年第3期18卷 199-216页

作者： Antonio sANTOs-OLMO Luis Enrique sÁNCHEZ David g.ROsADO Manuel A.sERRANO Carlos BLANCO Haralambos MOURATIDIs Eduardo FERNÁNDEZ-MEDINA gsyA Research group University of Castilla-La ManchaCiudad Real 13071Spain Institute for Analytics and Data science University of EssexColchester CO43SQUK Alarcos Research group University of Castilla-La ManchaCiudad Real 13071Spain IsTR Research group Department of Computer Science and ElectronicsUniversity of CantabriaSantander 39005Spain

The information society depends increasingly on risk assessment and management systems as means to adequately protect its key information *** availability of these systems is now vital for the protection and evolution of ***,several factors have led to an increasing need for more accurate risk analysis *** are:the speed at which technologies evolve,their global impact and the growing requirement for companies to *** analysis processes must consequently adapt to these new circumstances and new technological *** objective of this paper is,therefore,to present the results of an exhaustive analysis of the techniques and methods offered by the scientific community with the aim of identifying their main weaknesses and providing a new risk assessment and management *** analysis was carried out using the systematic review protocol and found that these proposals do not fully meet these new *** paper also presents a summary of MARIsMA,the risk analysis and management framework designed by our research *** basis of our framework is the main existing risk standards and proposals,and it seeks to address the weaknesses found in these *** is in a process of continuous improvement,as is being applied by customers in several European and American *** consists of a risk data management module,a methodology for its systematic application and a tool that automates the process.

关键词： information security management security system security risk assessment and management

Assessing the biennial conference on science and technology(BICOsT IX)2023 technical output on renewable energy,energy storage,and green hydrogen in line with UN sDg commitments

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Clean Energy 2024年第2期8卷 85-88页

作者： s.K.B.D.silva K.g.D.Piyumali Rasitha Thilini suranjana Perera K.D.K.g.Kaluarachchi Thilini Munagamage R.M.R.Ahammed C.s.P.Piyankarage seyed shahmy Veranja Karunaratne National science and Technology Commission of sri Lanka ColomboSri Lanka sri Lanka Technological Campus(sLTC) PadukkaSri Lanka University of Peradeniya PeradeniyaSri Lanka

The development,production and utilization of renewable energy,energy storage and green hydrogen and the associated technologies in sri Lanka have great potential to contribute to the United Nations’sustainable Development goals(sDgs).The island aims to achieve 70%electricity generation from renewable energy sources by 2030(within the target of 40%utilization of renewable energy sources for the entire energy generation of the country by 2030).The power sector has to invest Us$11 billion from 2023 to 2030 to contribute to reaching this *** commentary aims to provide a critical perspective on the recommendations of the report from the National science and Technology Commission’s 9th biennial conference in 2023 on science and technology,the sub-thematic technical report on clean energy,energy storage and green hydrogen in line with the sDgs in the sri Lankan *** technical report provides insightful recommendations for sri Lanka’s energy sector under three main sections:renewable energy,energy storage and green ***,it explores the potential of various renewable energy sources,energy storage systems and green hydrogen as sustainable solutions to address the country’s energy challenges while emphasizing the spillover effects of them,which could contribute to the enterprise’s job creation and uplift the economy.

关键词： renewable energy energy storage green hydrogen sustainable development goals sri Lanka social economic environmental sustainable affordable

Nickel-based cerium zirconate inorganic complex structures for CO_(2)valorisation via dry reforming of methane

维普期刊数据库评论

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 Environmental sciences 2024年第6期140卷 12-23页

作者： Juan Luis Martín-Espejo Loukia-Pantzechroula Merkouri Jesús gándara-Loe José Antonio Odriozola Tomas Ramirez Reina Laura Pastor-Pérez Department of Inorganic Chemistry and Material sciences Institute of seville University of Seville-CSICSeville 41092Spain Department of Chemical and Process Engineering University of SurreyGuildford GU27XHUnited Kingdom

The increasing anthropogenic emissions of greenhouse gases(gHg)is encouraging extensive research in CO_(2)*** reforming of methane(DRM)depicts a viable strategy to convert both CO_(2)and CH4into syngas,a worthwhile chemical *** the different active phases for DRM,the use of nickel as catalyst is economically favourable,but typically deactivates due to sintering and carbon *** stabilisation of Ni at different loadings in cerium zirconate inorganic complex structures is investigated in this work as strategy to develop robust Ni-based DRM *** and TPR-H2analyses confirmed the existence of different phases according to the Ni loading in these ***,superficial Ni is observed as well as the existence of a CeNiO_(3)perovskite *** catalytic activity was tested,proving that 10 wt.%Ni loading is the optimum which maximises *** catalyst was also tested in long-term stability experiments at 600and 800℃in order to study the potential deactivation issues at two different *** 600℃,carbon formation is the main cause of catalytic deactivation,whereas a robust stability is shown at 800℃,observing no sintering of the active phase evidencing the success of this strategy rendering a new family of economically appealing CO_(2)and biogas mixtures upgrading catalysts.

关键词： CO_(2)conversion Dry reforming of methane Nickel catalysts Pyrochlore Cerium zirconate

Excellent photoluminescence and electrochemical properties of sm^(3+) doped Ca_(2)Mgsi_(2)O_(7) nanophosphor:Display and electrochemical sensor 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 Department of Physics BMS Institute of Technology and ManagementBangalore560064India Department of Chemistry BMS Institute of Technology and ManagementBangalore560064India Department of Chemistry School of Applied SciencesREVA UniversityBangalore560064India Energy Materials ResearchLaboratory Department of ChemistrySiddaganga Institute of TechnologyTumakuru57203KarnatakaIndia school of Physical sciences REVA UniversityBangalore560057Indi Department of Physics Govt.Science CollegeBengaluru560001India Department 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 purity of the samples were confirmed by the powder X-ray diffraction(PXRD)*** single-phase tetragonal structure is observed from the PXRD results with no additional impurity *** 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 *** particle size was evaluated by transmission electron microscopy(TEM)and is found to be~50 *** interplanar distance is found to be 0.53 *** properties were systematically studied in *** phosphors are successfully excited at 403 nm NUV light,producing reddish-orange characteristic *** emission peaks are centered at 558(^(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 temperature(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 purity is found to be~82%.sm^(3+)incorporated 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 purity sensors Rare earths