检索结果-南通市图书馆

Microstructural evolution of ternary Ag33Cu-42Ge25 eutectic alloy inside ultrasonic field

在线全文

学校读者我要写书评

暂无评论

Progress in Natural Science:Materials International 2014年第6期24卷 642-648页

作者： Wei Zhai Xiaoyu Lu Bingbo Wei Department of Applied Physics Northwestern Polytechnical University

Ultrasonic field with a frequency of 20 k Hz is introduced into the solidification process of ternary Ag33Cu42Ge25 eutectic alloy from the sample bottom to its top. The ultrasound stimulates the nucleation of alloy melt and prevents its bulk undercooling. At low ultrasound power of 250 W,the primary ε2phase in the whole alloy sample grows into non-faceted equiaxed grains, which differs to its faceted morphology of long strip under static condition. The pseudobinary(Ag t ε2) eutectic transits from dendrite shape grain composed of rod type eutectic to equiaxed chrysanthemus shape formed by lamellar structure. By contrast, the ultrasound produces no obvious variation in the morphology of ternary(Ag t Ge t ε2) eutectic except a coarsening effect. When ultrasound power rises to 500 W, divorced ternary(Ag t Ge t ε2) eutectic forms at the sample bottom. However, in the upper part, the ultrasonic energy weakens, and it only brings about prominent refining effect to primary ε2phase.The microstructural evolution mechanism is investigated on the cavitation, acoustic streaming and acoustic attenuation.

关键词： Dynamic solidification Cavitation effect ternary alloy Nucleation Eutectic growth

PdMoSb trimetallene as high-performance alcohol oxidation electrocatalyst

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Nano Research 2023年第2期16卷 2041-2048页

作者： Junfeng Liu Qiuxia Wang Tong Li Yong Wang Huaming Li Andreu Cabot Institute for Energy Research School of Chemistry and Chemical EngineeringJiangsu UniversityZhenjiang 212013China Catalonia Institute for Energy Research-IREC Sant Adriàde BesòsBarcelona 08930Spain ICREA Pg.Lluís Companys 23Barcelona 08010Spain

Metallenes are an emerging class of two-dimensional(2D)material with outstanding potential in electrocatalysis.Herein,we present a new PdMoSb trimetallene produced by a facile wet-chemistry procedure and tested for the alcohol oxidation reaction.PdMoSb shows an extremely high Pd utilization and superior performance toward ethanol,methanol,and glycerol electro-oxidation compared with PdMo and commercial Pd/C catalysts.Experimental results and density functional theory calculations reveal that the enhanced activity relies not only on the high surface area that characterizes the ultrathin 2D metallene structure,but also on the particular electronic configuration of Sb.Sb facilitates OH−adsorption in the reactive-intermediate pathway and strongly enhances the CO tolerance in the poisoning-intermediate pathway for alcohol oxidation.The excellent alcohol oxidation performance of PdMoSb trimetallene demonstrates the high potential of multimetallenes in the field of electrocatalysis.

关键词： metallene ternary alloy 2D material alcohol oxidation reaction electrocatalysis

Thermally-triggered grain boundary relaxation in a nanograined Ni-Mo-W alloy

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

Nano Research 2023年第11期16卷 12800-12808页

作者： Dongsong Zeng Jiongxian Li Yinong Shi Xiuyan Li Ke Lu Shenyang National Laboratory for Materials Science Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China School of Materials Science and Engineering University of Science and Technology of ChinaShenyang 110016China

Conventionally,nanograined metals and alloys can be stabilized through segregating foreign elements at grain boundaries(GBs).Yet such an effect may be offset by formation of second phase at elevated temperatures.In this paper,by introducing minor W into a binary Ni-Mo alloy,we found precipitation of intermetallic phases was suppressed,enhancing thermal stability of the nanograined structure.Characterized faceted GBs and a high-fraction ofΣ3 coincidence site lattice(CSL)boundaries illustrate that GB structures are relaxed by formation of copious annealing twins.Adding W reduces stacking fault energy of the solid solution and facilitates the thermally-triggered GB relaxation.Suppressed precipitation of the intermetallic phases may be attributed to depletion of solutes at relaxed GBs.

关键词： grain boundary relaxation nanograined ternary alloy thermal stability stacking fault energy

Facile integration of an Al-rich Al_(1-x)In_(x)N photodetector on free-standing GaN by radio-frequency magnetron sputtering

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

Chinese Physics B 2023年第11期32卷 591-597页

作者：刘新科林之晨林钰恒陈建金邹苹周杰李博沈龙海朱德亮刘强俞文杰黎晓华顾泓王新中黄双武 College of Materials Science and Engineering Institute of Microelectronics(IME)Guangdong Research Center for Interfacial Engineering of Functional MaterialsShenzhen UniversityShenzhen 518060China School of Science Shenyang Ligong UniversityShenyang 110159China State Key Laboratory of Functional Materials for Informatics Shanghai Institute of Microsystem and Information TechnologyChinese Academy of SciencesShanghai 200050China Gusu Laboratory of Materials Science Suzhou 215123China Information Technology Research Institute Shenzhen Institute of Information TechnologyShenzhen 518172China

Al_(1-x)In_(x)N, a Ⅲ-nitride semiconductor material, is currently of great research interest due to its remarkable physical properties and chemical stability. When the Al and In compositions are tuned, its band-gap energy varies from 0.7 eV to 6.2 eV, which shows great potential for application in photodetectors. Here, we report the fabrication and performance evaluation of integrated Al_(1-x)In_(x)N on a free-standing GaN substrate through direct radio-frequency magnetron sputtering.The optical properties of Al_(1-x)In_(x)N will be enhanced by the polarization effect of a heterostructure composed of Al_(1-x)In_(x)N and other Ⅲ-nitride materials. An Al_(1-x)In_(x)N/Ga N visible-light photodetector was prepared by semiconductor fabrication technologies such as lithography and metal deposition. The highest photoresponsivity achieved was 1.52 A·W^(-1)under 365 nm wavelength illumination and the photodetector was determined to have the composition Al0.75In0.25N/GaN.A rise time of 0.55 s was observed after transient analysis of the device. The prepared Al_(1-x)In_(x)N visible-light photodetector had a low dark current, high photoresponsivity and fast response speed. By promoting a low-cost, simple fabrication method,this study expands the application of ternary alloy Al_(1-x)In_(x)N visible-light photodetectors in optical communication.

关键词： Ali-xIn N photodetector GaN radio-frequency magnetron sputtering ternary alloy

Phase diagram calculation and predication of Au–Pd–Zr ternary system

在线全文

学校读者我要写书评

暂无评论

Rare Metals 2017年第2期36卷 142-146页

作者： Jie Yu Lin-Jing Liu Shou-Dong Chen Jing-Chao Chen Faculty of Material Science and Engineering Kunming University of Science and Technology Mechanical Engineering and Automation Department Hunan Biological and Electromechanical Polytechnic

Au-Pd-Zr ternary alloy phase diagram at 25℃ was calculated by Panda phase calculation software,and the thermodynamic data were based on three binary alloy phase diagrams：Pd-Au,Au-Zr,and Pd-Zr.Five composition points in the ternary phase diagram were selected to predict the precipitation order.One（32Au-32Pd-36Zr） of the five composition points in ternary phase diagram was chosen to verify the correctness of the phase diagram calculation and the precipitation order by scanning electron microscopy（SEM）,energy dispersive spectroscopy（EDS）,and X-ray diffraction（XRD）.The unknown phase in XRD patterns was predicated by EDS and materials studio（MS） software.The experimental results show that there are seven key ternary reactions points and 17 phase regions in all isothermal sections at 25℃.The thermodynamic process and microstructure for the alloy phase can be described in order according to the vertical section in phase diagram.The phase compositions of the chosen one point are consistent with calculation prediction.The unknown phase in XRD patterns should be Zr_2AuPd by the first principle X-ray simulation.

关键词： Calculated phase diagram ternary alloy Thermodynamic Phase transformation Annealing

A high dispersed Pt_(0.35)Pd_(0.35)Co_(0.30)/C as superior catalyst for methanol and formic acid electro-oxidation

在线全文

学校读者我要写书评

暂无评论

Chinese Chemical Letters 2014年第6期25卷 907-911页

作者： Ying-Xia Wang Tie-Hong Chen Institute of New Catalytic Materials Science Key Laboratory of Advanced Energy Materials Chemistry(MOE)College of ChemistryCollaborative Innovation Center of Chemical Science and Engineering(Tianjin)Nankai University

Pt：Pd：Co ternary alloy nanoparticles were synthesized by sodium borohydride reduction under nitrogen, and were supported on carbon black as catalysts for methanol and formic acid electro-oxidation. Compared with Pt0.65C00.35/C, Pt/C, Pd0.65C00.35/C, and Pd/C catalyst, Pt0.35Pd0.35Co0.30/C exhibited relatively high durability and strong poisoning resistance, and the Pt-mass activity was 3.6 times higher than that of Pt/C in methanol oxidation reaction. Meanwhile, the Pt0.35Pd0.35Co0.30/C exhibited excellent activity with higher current density and higher CO tolerance than that of Pt0.6sCo0.35/C, Pt/C, Pd0.65C00.35/ C, and Pd/C in formic acid electro-oxidation.

关键词： Fuel cell ternary alloy Formic acid oxidation Methanol electro-oxidation