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PARTICLE SIZE AND MICROSTRUCTURE OF Ni NANOPOWDERS PREPARED BY ANODIC ARC PLASMA

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Acta Metallurgica Sinica(English Letters) 2005年第3期18卷 209-216页

作者： Z.q.Wei H.X.qiao j.F.Dai W.j.Feng q.Wang P.X.Yan SchoolofSciences LanzhouUniversityofTechnologyLanzhou730050China CollegeofCivilEngineering LanzhouUniversityofTechnologyLanzhou730050China SchoolofPhysicalScienceandTechnology LanzhouUniversityLanzhou730000China

Pure Ni nanopowders were successfully prepared by the method of anodic arc disch arged plasma with homemade experimental apparatus. The particle size, mircostruc ture and morphology of the particles by this process were characterized via X-ra y powder diffraction (XRD), transmission electron microscopy (TEM) and the corre sponding selected area electron diffraction (SAED); The specific surface area an d pore parameters were investigated by multi-point full analysis of nitrogen ads orption-desorption isotherms at 77K by Brunauer- Emmett-Teller (BET) surface are a analyzer; The chemical composition were determined by X-ray energy dispersive spectrometry (XEDS) equipped in SEM and element analyze instrument. The experime nt results indicate that the samples by this method with high purity,the crystal structure of the particles is as same as the bulk material, is fcc structure, w ith average particle sizes about 47nm, ranging from 20 to 70nm, and distributed uniformly in spherical chain shapes, the specific surface areavis 14.23m2/g, po re volume of pore is 0.09cm3/g and average pore diameter is 23nm.

关键词： anodic arc plasma Ni nanopowder particle size structure composition.

支架特异性脂肪衰减指数与PCI术后靶血管血运重建相关

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国际医学放射学杂志 2024年第2期 251-252页

作者： F.Xu C.C.Wang q.Tao j.Zhang M.M.Zhao S.W.Shi 潘红利

摘要目的探讨支架特异性血管周围脂肪衰减指数（FAI）在支架植入病人中的临床相关性。方法回顾性纳入162例在支架植入后接受连续冠状动脉CT血管成像

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Laser ablation and structuring of CdZnTe with femtosecond laser pulses

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journal of Materials Science & Technology 2020年第13期47卷 180-185页

作者： j.j.j.Nivas E.Allahyari A.Vecchione q.Hao S.Amoruso X.Wang Dipartimento di Fisica“Ettore Pancini” Universitàdi Napoli“Federico II”Via CintiaI-80126 NapoliItaly CNR-SPIN UOS NapoliVia CintiaI-80126 NapoliItaly CNR-SPIN UOS SalernoVia Giovanni Paolo II132I-84084 Fisciano(SA)Italy North China Research Institute of Electro-Optics Beijing 100015China School of Remote Sensing and Information Engineering Wuhan UniversityWuhan 430072China

We report an experimental investigation on laser ablation and associated surface structuring of CdZnTe by femtosecond Ti:Sa laser pulses(laser wavelengthλ≈800 nm,≈35 fs,10 Hz),in *** exploiting different static irradiation conditions,the fluence threshold and the incubation effect in CdZnTe are ***,surface treatment with a low laser fluence(laser pulse energy E≈5-10_μj)and number of shots(5j)results in the formation of welldefined laser-induced periodic surface structures(LIPSS)in the outskirts of the main crater,where the local fluence is well below the material ablation *** low spatial frequency and high spatial frequency LIPSS perpendicular to the laser polarization are found together and separately depending on the irradiation *** are ascribed to a process of progressive aggregation of randomly distributed nanoparticles produced during laser ablation of the deep crater in the region of the target irradiated by a fluence below the ablation threshold with many laser pulses.

关键词： Laser ablation Femtosecond laser surface processing CdZnTe Laser induced periodic surface structures Laser processing

Secondary relaxation and dynamic heterogeneity in metallic glasses：A brief review

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Chinese Physics B 2017年第1期26卷 32-41页

作者： j C qiao[[ q Wang D Crespo Y Yang j M Pelletier School of Mechanics Civil Engineering and Architecture Northwestern Polytechnical University Xi＇an 710072 China Centre for Advanced Structural Materials Department of Mechanical and Biomedical Engineering City University of Hong Kong Kowloon Tong Kowloon Hong Kong China Universite de Lyon MATEIS UMR CNRS5510 Bat. B. Pascal INSA-Lyon F-69621 Villeurhanne cedex France Key Laboratory for Structures Institute of Materials Science Shanghai University Shanghai 200444 China Departament de Fisica EETAC Universitat Politecnica de Catalunya 08860-Castelldfels Barcelona Spain

Understanding mechanical relaxation, such as primary（α） and secondary（β） relaxation, is key to unravel the intertwined relation between the atomic dynamics and non-equilibrium thermodynamics in metallic glasses. At a fundamental level, relaxation, plastic deformation, glass transition, and crystallization of metallic glasses are intimately linked to each other, which can be related to atomic packing, inter-atomic diffusion, and cooperative atom movement. Conceptually, βrelaxation is usually associated with structural heterogeneities intrinsic to metallic glasses. However, the details of such structural heterogeneities, being masked by the meta-stable disordered long-range structure, are yet to be understood. In this paper, we briefly review the recent experimental and simulation results that were attempted to elucidate structural heterogeneities in metallic glasses within the framework of β relaxation. In particular, we will discuss the correlation amongβ relaxation, structural heterogeneity, and mechanical properties of metallic glasses.

关键词： metallic glass structural heterogeneity mechanical property secondary relaxation

Synthesis of Single-Crystal TiO_2 Nanowire Using Titanium Monoxide Powder by Thermal Evaporation

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journal of Materials Science & Technology 2012年第5期28卷 385-390页

作者： Z.G.Shang Z.q.Liu P.j.Shang j.K.Shang Shenyang National Laboratory for Materials Science Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China

TiO 2 nanowires were synthesized successfully in a large quantity by thermal evaporation using titanium monoxide powder as precursor. X-ray diffraction results showed that all the products were pure rutile phase of TiO 2 . According to microstructural observations, the nanowires have two typical morphologies, a long straight type and a short tortuous type. The straight nanowires were obtained at a wide temperature range of 900–1050 ℃, while the tortuous ones were formed below 900 ℃. Transmission electron microscopy characterization revealed that both the straight and the tortuous nanowires are single-crystal rutile TiO 2 . The preferential growth direction of the nanowires was determined as [110] orientation according to electron diffraction and high-resolution image analyses. The morphological change of TiO 2 nanowires was discussed by considering the different atomic diffusion rates of Ti atoms caused by the phase transformation in Ti substrate at around 900 ℃.

关键词： Rutile-TiO 2 Alloy nanowires Transmission electron microscopy (TEM) characterization Crystal structure identification Growth mechanism Thermal evaporation

American government The Essentials james q. Wilson, john j. Dilulio 8th ed.; postinaugural ed.

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American government The Essentials James Q. Wilson, John J. ...

Self-induced birefringence of white-light continuum generated by interaction of focused femtosecond laser pulses with fused silica

2001年

作者： james q. Wilson john j. Dilulio

来源：畅想之星图书光盘版（南... 评论

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畅想之星图书光盘版（南通市图书馆镜像）

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High Power Laser Science and Engineering 2020年第2期8卷 71-76页

作者： j.qian G.D.Wang K.Y.Lou D.Y.Shen q.Fu q.Z.Zhao State Key Laboratory of High Field Laser Physics Shanghai Institute of Optics and Fine MechanicsChinese Academy of SciencesShanghai 201800China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100049China

White-light continuum can be induced by the interaction of intense femtosecond laser pulses with condensed *** using two orthogonal polarizers,a self-induced birefringence of continuum is observed when focusing femtosecond laser pulses into bulk fused *** is,the generated white-light continuum is synchronously modulated anisotropically while propagating in fused ***-resolved detection confirms that self-induced birefringence of continuum shows a growth and saturation feature with time *** adjusting laser energy,the transmitted intensity of continuum modulated by self-induced birefringence also varies *** analysis with time evolution indicates that it is the focused femtosecond laser pulses that induce anisotropic microstructures in bulk fused silica,and the anisotropic structures at the same time modulate the generated continuum.

关键词： femtosecond laser pulses fused silica self-induced birefringence white-light continuum

ELECTROCHEMICAL NOISE ANALYSIS OF THE INFLUENCE OF THE Zn^(2+)IONS CONCENTRATION ON ZINC ELECTROPLATING

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Acta Metallurgica Sinica(English Letters) 2005年第2期18卷 137-144页

作者： Z.Zhang C.S.Wu q.Y.Cai F.H.Cao j.q.Zhang DepartmentofChemistry ZhejiangUniversityHangzhou310027China DepartmentofChemistry ZhejiangUniversityHangzhou310027China／／StateKeyLaboratoryforCorrosionandProtectionInstituteofMetalResearchTheChineseAcademyofSciencesShenyang110016China

The influence of the concentration of Zn2+ ions on zinc electroplating process was investigated by means of electrochemical noise (EN) and cyclic voltammetry methods in conjunction with the scanning electron microscopy (SEM) technique. It was found that the EN generated during the electroplating of dentritic or large polymeric zinc deposit has large potential oscillation amplitude and positive potential drift while the compact zinc deposit possesses small noise amplitude and little potential drift. With the change of rate determining step from diffusion-control through mixed-control to activation-control, the maximum relative energy obtained from wavelet analysis defined from the region with larger scales to those with smaller scales, and the EDP (relative energy distribution plot) can be us, as 'fingerprints' of EN to characterize the electroplating process and the deposit structure. The results also showed that electrochemical noise technique can give more information about the electrodeposit structure than other normal electrochemical measurements, such as linear potential sweep method and cyclic voltammetry technique.

关键词： zinc electroplating zinc ions concentration electrochemical noise electrodeposit structure

MAKING DUCTILE CAST IRON WITH ESR PROCESS

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Acta Metallurgica Sinica(English Letters) 1998年第3期11卷 169-174页

作者： S.j.Chu H.H.Lou q.Niu Univ of Science and Technology Beijing Beijing China

Making ductile cast iron with ESR process under D.C. condition without adding spheroidizing inoculant alloys has been studied in laboratory. The key operation of ESR for cast iron is increasing the silicon content in unrefined consumable electrodes of flake graphite cast iron and using CaF2-based slags containing rare-earth or basic oxides and magnesium fluoride. The samples excel ductile cast iron produced by general technological process in fatigue strength and sealing performance.

关键词： ductile cast iron electroslag remelting nodulizing element