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Effects of welding parameters and post-heat treatment on mechanical properties of friction stir welded AA2195-T8 Al-Li alloy

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journal of Materials science & Technology 2018年第1期34卷 219-227页

作者： j. Zhang X.s. Feng j.s. Gao H. Huang Z.Q. Ma L.j. Guo Technical Center Shanghai Aerospace Equipments Manufacturer Shanghai 200245. China

In this study, the effects of main welding parameters （rotation speed （ω） and welding speed （υ）） on the microstructure, micro-hardness distribution and tensile properties of friction stir welded （FsW） 2195-T8 Al-Li alloy were investigated. The effects of T6 post-treatments at different solution and aging conditions on the mechanical properties and microstructure characteristics of the FsW joints were also investigated. The results show that with increasing to and v, both strength and elongation of the joints increase first, and then decrease with further increase of ω and υ. All the joints under varied welding parameters show significant strength loss, and the strength reaches only 65% of the base metal, The effect of T6 post-heat treatment on the mechanical properties of the joints depends on the solution and aging conditions. Two heat treatment processes （480 ℃×0.5 h quenching＋ 180 ℃× 12 h, 520 ℃× 0.5 h quenching＋ 180 ℃×12h aging） are found to increase the joint strength. Furthermore, low temperature quenching （480℃） is more beneficial to the joint strength. The joint strength can reach 85% of the base metal. Whereas both low temperature aging （140 ℃× 56h） and stepped aging （ 100 ℃× 12 h ＋ 180 ℃× 3 h） processes decrease the joint strength. After heat treatment all the joints show decreased ductility due to the obvious grain coarsening in the nugget zone （NZ） and thermo-mechanically affected zone （TMAZ）.

关键词： 2195-T8 Al-Li alloy Friction stir welding Welding parameters Post-heat treatment

Property enhancement of cast iron used for nuclear casks

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International journal of Minerals,Metallurgy and Materials 2016年第1期23卷 40-48页

作者： R.K. Behera B.P. Mahto j.s. Dubey s.C. Mishra s. sen Department of Metallurgical and Materials Engineering National Institute of Technology Rourkela Odisha 769008 India Bhaba Atomic Research Centre (Post Irradiation Examination Division) Mumbai 400085 India

Ductile iron （DI） is a preferred material for use in various structural, automotive, and engineering fields because of its excellent combination of strength, toughness, and ductility. In the current investigation, we elucidate the relationship between the morphological and mechanical properties of DI intended for use in safety applications in the nuclear industry. DI specimens with various alloying elements were subjected to annealing and austempering heat treatment processes. A faster cooling rate appeared to increase the nodule count in austempered specimens, compensating for their nodularity value and subsequently decreasing their ductility and impact strength. The ductility and impact energy values of annealed specimens increased with increasing ferrite area fraction and nodularity, whereas an increase in the amounts of Ni and Cr resulted in an increase of hardness via solid solution strengthening. Austempered specimens were observed to be stronger than an- nealed specimens and failed in a somewhat brittle manner characterized by a river pattern, whereas the ductile failure mode was character- ized by the presence of dimples.

关键词： ductile iron nodularity mechanical properties failure modes nuclear industry

DIRECTION AMBIGUITY REsOLUTION FROM sAR IMAGERY: A NEW APPROACH

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journal of Hydrodynamics 2001年第1期13卷 99-102页

作者： Yang, j.s. Huang, W.G. Zhou, C.B. state Oceanic Administration Hangzhou 310012 China

Ambiguity problem is inherent in synthetic aperture radar (sAR) images of ocean waves. A new method is developed based on the propagation theory of gravity waves to remove this kind of ambiguity from a single frame of... 详细信息

关键词： Oceanographic instruments Water waves

Reply to Letter by Dr. Christoph Kupferschmid： Commentary on ＂Countries with high circumcision prevalence have lower prostate cancer mortality＂

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Asian journal of Andrology 2016年第6期18卷 950-951页

作者： Mitchell s Wachtel shengping Yang Brian j morris Texas Tech University Health sciences Center Lubbock Texas USA school of Medical sciences University of Sydney Sydney New South Wales Australia

Dear Editor, We thank Dr. Kupferschmid for his interest in our study, which examined male circumcision （MC） and prostate cancer mortality〉2 Considerable strong evidence has been accumulated since 1951.3 Most of his references4-10 do not address MC and the risk of death from prostate cancer. That is a different question than MC and the risk of developing prostate cancer, which none of his references validly assess. One reference addressed bacterial colonization,6 not prostate cancer. Another7 concerned sexually transmitted infections and prostate cancer.

关键词： @@

MICROWAVE PERMEABILITY sPECTRA OF sPUTTERED Fe-Co-B sOFT MAGNETIC THIN FILMs

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维普期刊数据库

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Acta Metallurgica sinica(English Letters) 2008年第6期21卷 419-424页

作者： j.s. Liao Z.K. Feng j. Qiu Y. Q. Tong Department of Electronic science and Technology Huazhong University of Science and Technology Wuhan 430074 China

Permeability characteristics of sputtered soft magnetic Fe40Co40B20 thin films are investigated in the range of O. 5 to 5 GHz by a shortened microstrip transmission line perturbation method. Excellent microwave permeability is achieved at 0.4 Pa argon pressure： fr is 3.32 GHz, the real and imaginary part of permeability at 0.5 GHz are 104 and 61, respectively. In addition, the thickness effect on permeability is also studied. The minimum damping can be achieved at the thinnest film. Different sources contributed to in-plane anisotropy are discussed briefly. The deviation between the peak frequency of the imaginary part and the zero-crossing frequency of the real part of permeability is also presented.

关键词： Fe-Co-B In-plane anisotropy Magnetic thin films Permeability

EFFECT OF HEAT TREATMENTs ON THE MICROsTRUCTURE AND TRANsFORMATION CHARACTERIsTICs OF TiNiPd sHAPE MEMORY ALLOY THIN FILMs

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Acta Metallurgica sinica(English Letters) 2005年第6期18卷 707-713页

作者： C.C. Zhang C.s. Yang G.F. Ding s. Q. Qian j.s. Wu National Key Laboratory of Nano/Micro Fabrication Technology Key Laboratory for Thin Film and Microfabrication of Ministry of Education Institute of Micro and Nano Science and Technology Shanghai Jiaotong University Shanghai 200030 China school of Material science and Engineering Shanghai Jiaotong University Shanghai 200030 China

Microstructure and phase transformation behaviors of the film annealed at different temperatures were studied by X-ray diffractometry （XRD）, transmission electron microscopy and differential scanning calorimeter （DsC）. Also tensile tests were examined. For increasing annealed temperature, multiple phase transformations, transformations via a B19-phase or direct martensite/austenite transformtion are observed. The TiNiPd thin film annealed at 750℃ had relatively uniform martensite/austenite transformtion and shape memory effect. Martensite/austenite transformtion was also found in strain-temperature curves. subsequent annealing at 450℃ had minor effect on transformation temperatures of Ti-Ni-Pd thin films but resulted in more uniform transformation and improved shape memory effect.

关键词： Ti-Ni-Pd thin films microstructure martensitic phase transformation,shape memory effect

sTRUCTURE IMPROVEMENT AND TEMPERATURE FIELD sIMULATION OF PREPARING NANOPOWDER BY EVAPORATION-CONDENsATION METHOD

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Acta Metallurgica sinica(English Letters) 2008年第3期21卷 178-182页

作者： j.s. Bao Y. Yin T.G. Liu Z.Y. Yang school of Mechanical and Electrical Engineering China University of Mining and Technology Xuzhou221116 China

A new apparatus, with a segregable conical water cooling condenser, which is heated by an electric arc using the evaporation-condensation method to prepare carbon-coated nanopowder, has been developed by the authors. Numerical simulation of the temperature field is done by the ANsYs software, and temperature in the reaction vessel is measured with the help of an experiment, to verify the simulation result. Influence of the temperature field in the reaction vessel, on the process of preparing nanopowder is then discussed simply. It is shown that the segregable conical water cooling condenser and carbon-coated surface process can be used to prepare steady carbon-coated metal nanopowder, at a lower cost and higher yield rate than the traditional structure. simulation of the temperature field in the apparatus shows that the arc heating method can form a temperature field in the apparatus, which is quite favorable for nanopowder formation. Experiments show that the rational parameters using this apparatus, with the arc heating method to prepare carbon-coated nanopowder are electricity 60-100 A and arc length 5-8 mm.

关键词： Evaporation-condensation method Electric arc heating Temperature field Condenser structure

A systematic review of progenitor survival and maturation in Parkinsonian models

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Neural Regeneration Research 2025年第11期20卷 3172-3178页

作者： Giulia Comini Eilís Dowd Pharmacology&Therapeutics and Galway Neuroscience Center University of GalwayGalwayIreland

stem cell-based brain repair is a promising emergent therapy for Parkinson's disease based on years of foundational research using human fetal donors as a cell *** current therapeutic options for patients,this approach has the potential to provide longterm stem cell–derived reconstruction and restoration of the dopaminergic input to denervated regions of the brain allowing for restoration of certain functions to *** ultimate clinical success of stem cell–derived brain repair will depend on both the safety and efficacy of the approach and the latter is dependent on the ability of the transplanted cells to survive and differentiate into functional dopaminergic neurons in the Parkinsonian *** the pre-clinical literature suggests that there is considerable variability in survival and differentiation between studies,the aim of this systematic review was to assess these parameters in human stem cell-derived dopaminergic progenitor transplant studies in animal models of Parkinson's disease.A defined systematic search of the PubMed database was completed to identify relevant studies published up to March *** screening,76 articles were included in the analysis from which 178 separate transplant studies were *** these,graft survival could be assessed in 52 studies and differentiation in 129 ***,we found that graft survival ranged froms transplanted,with a median of 51%of transplanted cells surviving in the brain;while dopaminergic differentiation of the cells ranged from 0% to 46% of cells transplanted with a median of 3%.This systematic review suggests that there is considerable scope for improvement in the differentiation of stem cell-derived dopaminergic progenitors to maximize the therapeutic potential of this approach for patients.

关键词： cell replacement therapy differentiation embryonic stem cells graft induced pluripotent stem cells Parkinson's disease survival transplant

Re: Amparore D, Pecoraro A, Piramide F, Verri P, Checcucci E, De Cillis s, et al. Three-dimensional imaging reconstruction of the kidney's anatomy for a tailored minimally invasive partial nephrectomy: A pilot study. Asian j Urol 2022;9:263-71.: A further step towards personalized surgery through virtual clip application

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Asian journal of Urology 2023年第1期10卷 113-114页

作者： Philippe C.Grange Paul T.morris Heather L.Benz William A.Buggele Raymond s.Fryrear johnson&johnson MedTech NorderstedtSchleswig-HolsteinGermany johnson&johnson MedTech Santa ClaraCAUSA johnson&johnson MedTech CincinnatiOHUSA

Dear Editor,We have read with great interest the outstanding article authored by Amparore et al.[1].We commend the authors for their large interventional study of 222 patients observing a favorable impact on clinical outcomes after implementation of three-dimensional(3D)modeling for laparoscopic partial nephrectomy robotically assisted or not,compared to a historical group of *** authors presented convincing results and humbly acknowledge limitations of the study,notably its *** results extend growing awareness in urology that 3D modeling can enhance surgeons’case planning[2].

关键词： anatomy dimensional