检索结果-南通市图书馆

Heavily Ag doped zinc-borate glasses for UV-driven white light generation with high quantum yield

在线全文

学校读者我要写书评

暂无评论

Heavily Ag doped zinc-borate glasses for UV-driven white lig...

Acceleration of 60 MeV proton beams in the commissioning experiment of the SULF-10 PW laser

中国稀土学会2017学术年会

作者： x.y.liu S.x.Dai Q.y.Zhang Laboratory of Infrared Materials and Devices The Advanced Technology Research InstituteNingbo University State Key Laboratory of Luminescent Materials and Devices and Institute of Optical Communication MaterialsSouth China University of Technology

White light-emitting diodes(W-LEDs) have attracted persistent attention in recent decades due to their magnificent *** the development of W-LEDs,one of the major concern problems is the degradation of epoxy resins which will lead to the chromatic aberration and poor white light *** this context,luminescent glasses as novel durable materials,possessing excellent optical properties,flexibility of size and shape as well as epoxy resin-free in assembly process,have been explored as potential candidates for ***,low luminescence quantum efficiency of the glass materials often limits the overall performance as white light *** way towards this problem relies on heavy doping activator to improve quantum efficiency of the emission process which can usually be achieved before concentration quenching of luminescence occurs [1].Amongst the activator ions proposed,Ag nanoclusters have appeared as a fascinating new class of activators for solar spectral transformation and warm-colored light *** on the host material doped with Ag nanoclusters,a tuning of Ag nanoclusters emission wavelength ranging from blue-green,yellow,red and eventually to near-infrared can be achieved comparable to that of semiconductors [3].Here,we report on a white luminescence from a heavily Ag doped zinc-borate oxyfluoride glasses with surprisingly high quantum *** by 365 nm,the specific glass system enables highly efficient white emission for AgNO dopant concentration up to 12 mol% before concentration quenching is *** allows for the realization of high absorption cross section combined with an internal quantum efficiency of greater than 70% without further optimization of batch materials and processing *** this way,the problem of luminescence quantum yield from active glass substrates in W-LEDs may be overcome.

关键词： Ag nanoclusters white emission high quantum efficiency oxyfluoride glasses

来源： cnki会议评论

在线全文

cnki会议

学校读者我要写书评

暂无评论

High Power Laser Science and Engineering 2022年第4期10卷 36-44页

作者： A.x.Li C.y.Qin H.Zhang S.Li L.L.Fan Q.S.Wang T.J.xu N.W.Wang L.H.yu y.xu y.Q.liu C.Wang x.L.Wang Z.x.Zhang x.y.liu P.L.Bai Z.B.Gan x.B.Zhang x.B.Wang C.Fan y.J.Sun y.H.Tang B.yao x.y.Liang y.x.Leng B.F.Shen L.L.Ji R.x.Li Z.Z.xu State Key Laboratory of High Field Laser Physics Shanghai Institute of Optics and Fine MechanicsChinese Academy of SciencesShanghai 201800China Shanghai Tech University Shanghai 201210China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBejing 100049China CAS Centerfor Excellence inUltra-intense Laser Science Shanghai 201800China College of Science University of Shanghai for Science and TechnologyShanghai 200093China Department of Physics Shanghai Normal UniversityShanghai 200234China

We report the experimental results of the commissioning phase in the 10 PW laser beamline of the Shanghai Superintense Ultrafast Laser Facility(SULF).The peak power reaches 2.4 PW on target without the last amplifying during the *** laser energy of 72±9 J is directed to a focal spot of approximately 6μm diameter(full width at half maximum)in 30 fs pulse duration,yielding a focused peak intensity around 2.0×10^(21)W/cm^(2).The first laser-proton acceleration experiment is performed using plain copper and plastic ***-energy proton beams with maximum cut-off energy up to 62.5 MeV are achieved using copper foils at the optimum target thickness of 4μm via target normal sheath *** plastic targets of tens of nanometers thick,the proton cut-off energy is approximately 20 MeV,showing ring-like or flamented density *** experimental results reflect the capabilities of the SULF-10 PW beamline,for example,both ultrahigh intensity and relatively good beam *** optimization for these key parameters is underway,where peak laser intensities of 10^(22)-10^(23)w/cm^(2)are anticipated to support various experiments on extreme field physics.

关键词： high-energy proton source laser-plasma interaction ultraintense lasers

Distinct Electrical and Mechanical Responses of a Cu-10Fe Composite Prepared by Hot-Pressed Sintering and Post Treatment

在线全文

学校读者我要写书评

暂无评论

Acta Metallurgica Sinica(English Letters) 2024年第2期37卷 255-265页

作者： x.y.yue S.y.Peng x.Zhang C.N.He y.Z.Tian Key Laboratory for Anisotropy and Texture of Materials(Ministry of Education) School of Materials Science and EngineeringNortheastern UniversityShenyang110819China School of Materials Science and Engineering and Tianjin Key Laboratory of Composite and Functional Materials Tianjin UniversityTianjin300350China Research Centre for Metallic Wires Northeastern UniversityShenyang110819China

A Cu-10wt%Fe composite was prepared through hot-pressed sintering,and the material was subsequently solution *** hot-pressed sintered and solution treated materials were rolled and *** precipitation behavior and performance changes were systematically studied by using scanning electron microscopy and transmission electron *** contrast to the hot-pressed sintered specimen,the solution treatment significantly affects the thermal stability and properties of the Cu-10wt%Fe *** Cu-10wt%Fe composite was prepared after solid solution,cold rolling and aging at 773 K for 1 h,and it obtained excellent tensile strength of 494 MPa,uniform elongation of 16.3%,electrical conductivity of 51.1%IACS and softening temperature of 838 *** for the distinct difference in thermal stability and properties between hot-pressed sintered and solution treated specimens were *** findings provide a theoretical basis for designing high-performance Cu-based in-situ composites by post treatment.

关键词： Cu-Fe composite Hot-pressed sintering Thermal stability Strength Electrical conductivity

Microstructure evolution and shape memory behaviors of Ni_(47)Ti_(44)Nb_(9)alloy subjected to multistep thermomechanical loading with different prestrain levels

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 Materials Science & Technology 2024年第4期171卷 80-93页

作者： y.H.Zhang H.Li Z.W.yang x.liu Q.F.Gu State Key Laboratory of Solidification Processing School of Materials Science and EngineeringNorthwestern Polytechnical UniversityXi’an 710072China Shaanxi Key Laboratory of High-Performance Precision Forming Technology and Equipment Northwestern Polytechnical UniversityXi’an 710072China

Ni_(47)Ti_(44)Nb_(9)shape memory alloy(SMA)is a promising material in the aerospace field due to its wide transformation *** application of shape memory effect depends on multistep thermomechan-ical loading,viz.,low-temperature deformation and subsequent heating to ***-temperature deformation prestrain plays a pivotal role in shape memory properties tailoring of SMA ***,microstructure evolution and deformation mechanisms of Ni_(47)Ti_(44)Nb_(9)SMA subjected to vari-ous prestrain levels are still *** this end,microstructure evolution and shape memory behaviors of Ni_(47)Ti_(44)Nb_(9)alloy subjected to multistep thermomechanical loading with prestrain levels of 8%-16%at-28℃(M_(s)+30℃)were *** results demonstrate that the stress-strain curve of the specimen exhibits four distinct stages at a maximal prestrain of 16%.Whereas stageⅡand stageⅢend at prestrains of∼8%and∼12%,*** stageⅡ,the stress-induced martensitic transformation is accompanied by the dislocation slip of the NiTi matrix andβ-Nb *** stageⅢ,in addition to the higher density of dislocations and further growth of stress-induced martensite variants(SIMVs),(001)compound twins are introduced as a result of the(001)deformation twinning in stress-induced ***{20-1}martensite twins are gradually introduced in stageⅣ.Correspondingly,after subsequent unloading and heating,a higher density of{114}austenite twins form in the specimen with a larger prestrain of 16%.With increasing prestrain from 8%to 16%,the recoverable strainε_(re)^(T)upon heating increases first and then ***ε_(re)^(T)obtains a maximum of 7.03%at 10%prestrain and de-creases to 6.17%at 16%*** increase ofε_(re)^(T)can be attributed to the formation of new SIMVs,the further growth of existing SIMVs,and the recoverable(001)compound *** the decrease ofε_(re)^(T)is mainly associated with the irrecoverable strain by{20−1}martensite *** effe

关键词： Ni_(47)Ti_(44)Nb_(9)shape memory alloy Wide transformation hysteresis Thermomechanical loading Microstructure evolution Shape memory behaviors Stress-induced martensitic transformation Deformation twinning

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

在线全文

维普期刊数据库

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)

Progress on the antiferromagnetic topological insulator MnBi2Te4

在线全文

学校读者我要写书评

暂无评论

National Science Review 2024年第2期11卷 33-49页

作者： Shuai Li Tianyu liu Chang liu yayu Wang Hai-Zhou Lu x.C.xie Department of Physics Harbin Institute of Technology Shenzhen Institute for Quantum Science and Engineering and Department of Physics Southern University of Science and Technology(SUSTech) Quantum Science Center of Guangdong-Hong Kong-Macao Greater Bay Area(Guangdong) Shenzhen Key Laboratory of Quantum Science and Engineering International Quantum Academy Beijing Academy of Quantum Information Sciences Beijing Key Laboratory of Optoelectronic Functional Materials&Micro-Nano Devices Department of Physics Renmin University of China State Key Laboratory of Low Dimensional Quantum Physics Department of PhysicsTsinghua University Frontier Science Center for Quantum Information Hefei National Laboratory International Center for Quantum Materials School of Physics Peking University Institute for Nanoelectronic Devices and Quantum Computing Fudan University

Topological materials, which feature robust surface and/or edge states, have now been a research focus in condensed maTher physics. They represent a new class of materials exhibiting nontrivial topological phases,and provide a platform for exploring exotic transport phenomena, such as the quantum anomalous Hall effect and the quantum spin Hall effect. Recently, magnetic topological materials have attracted considerable interests due to the possibility to study the interplay between topological and magnetic *** particular, the quantum anomalous Hall and axion insulator phases can be realized in topological insulators with magnetic order. MnBi2Te4, as the first intrinsic antiferromagnetic topological insulator discovered, allows the examination of existing theoretical predictions; it has been extensively studied, and many new discoveries have been made. Here we review the progress made on MnBi2Te4from both experimental and theoretical aspects. The bulk crystal and magnetic structures are surveyed first, followed by a review of theoretical calculations and experimental probes on the band structure and surface states, and a discussion of various exotic phases that can be realized in MnBi2Te4. The properties of MnBi2Te4thin films and the corresponding transport studies are then reviewed, with an emphasis on the edge state transport. Possible future research directions in this field are also discussed.

关键词： MnBi2Te4 magnetic topological insulator antiferromagnetic quantum anomalous Hall effect axion insulator

A perspective on age-related changes in cell environment and risk of neurodegenerative diseases

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Neural Regeneration Research 2024年第4期19卷 719-720页

作者： Alice y.liu Department of Cell Biology and Neuroscience Rutgers State University of New JerseyPiscatawayNJUSA

“Age-related neurodegenerative disease”underscores human age as the primary risk factor for disease development:Alzheimer’s,Parkinson’s,and Huntington’s disease(HD)as *** for the age-dependent delay in disease manifestation,in particular for autosomal dominant forms of the disease,and the underlying cause(s)of specific neuron dysfunction and death to manifest as memory loss,anxiety,depression,and agitation in disease subjects remain *** are interested in understanding age-related changes in cell environment that can modulate the structure,function,aggregation.

关键词： Huntington Alzheimer death

Rational design of AgGaS/ZnS/ZnS quantum dots with a near-unity photoluminescence quantum yield via double shelling scheme

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2期169卷 235-242页

作者： H.x.Lu H.liu Z.Z.Fu y.y.Chen H.Q.Dai Z.Hu W.L.Zhang R.Q.Guo Institute for Electric Light Sources School of Information Science and TechnologyFudan UniversityShanghai 200433China Institute of Future Lighting Academy for Engineering and TechnologyFudan UniversityShanghai 200433China yiwu Research Institute of Fudan University YiwuZhejiang 322000China Zhongshan-Fudan Joint Innovation Center Zhongshan 528437China

In this study,a two-step method was used to synthesize highly luminescent AgGaS/ZnS/ZnS quantum dots(QDs).In the first step,an inner ZnS shell was formed via a one-pot method,which resulted in a smaller lattice mismatch between the AgGaS core and the outer ZnS shell,thereby facilitating the formation of a thick outer *** the two-step shelling process,the synthesized AgGaS/ZnS/ZnS QDs showed an excellent photoluminescence quantum yield(PLQy)of 96.4%with a peak wavelength of 508 nm,repre-senting the highest PLQy reported thus far for AgGaS ***,the effect of halogen ions in Zn precursors on the shelling process was *** was proposed that the capacity of halogen ions to coordinate with the QDs influenced the balance between Zn cation diffusion and ZnS shelling ***,the ZnS shelling reaction was dominant when ZnCl_(2)was employed,while Zn cation diffusion was the dominant process under the I^(−)-rich *** work provides insights into the interfacial restructuring during the ZnS shelling and offers a clear map for the tailored synthesis of core/shell QDs.

关键词： AgGaS Quantum dots Photoluminescence Core/shell Alloyed core/shell interface

Effect of Al_(2)O_(3)on the Mechanical Properties of(B_(4)C+Al_(2)O_(3))/Al Neutron Absorbing Materials

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Acta Metallurgica Sinica(English Letters) 2024年第8期37卷 1411-1420页

作者： J.x.Cai B.M.Shi N.Li y.liu Z.G.Zhang y.N.Zan Q.Z.Wang B.L.xiao Z.y.Ma Shi‑Changxu Innovation Center for Advanced Materials Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China Key Laboratory of Nuclear Materials and Safety Assessment Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China Nuclear Equipment Division Beijing Institute of Nuclear EngineeringChina Nuclear Power Engineering Co.Ltd.Beijing 100840China Department of Materials Science School of Mechanical EngineeringShenyang UniversityShenyang 110044China

B_(4)C/Al composites are widely utilized as neutron absorbing materials for the storage and transportation of spent nuclear *** order to improve the high-temperature mechanical properties of B_(4)C/Al composites,in-situ nano-Al_(2)O_(3)was introduced utilizing oxide on Al powder *** this study,the Al_(2)O_(3)content was adjusted by utilizing spheroid Al powder with varying diameters,thereby investigating the impact of Al_(2)O_(3)content on the tensile properties of(B_(4)C+Al_(2)O_(3))/Al *** was found that the pinning effect of Al_(2)O_(3)on the grain boundaries could hinder the recovery of dislocations and lead to dislocation accumulation at high *** the result,with the increase in Al_(2)O_(3)content and the decrease in grain size,the high-temperature strength of the composites increased *** finest Al powder used in this investigation had a diameter of 1.4μm,whereas the resultant composite exhibited a maximum strength of 251 MPa at room temperature and 133 MPa at 350℃,surpassing that of traditional B_(4)C/Al composites.

关键词： Al matrix composites Neutron absorbing materials (B_(4)C+Al_(2)O_(3))/Al composites High-temperature strength