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STUDY OF THE INFLUENCE OF pH ON THE ELECTROCRYSTALLIz.TION OF z.NC

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Acta Metallurgica Sinica(English Letters) 2005年第4期18卷 497-504页

作者： z. zhang.W.H. Leng j. Q. zhang Department of Chemistry Zhejiang University Hangzhou 310027 China State Key Laboratory for Corrosion and Protection Institute of Metal Reseach The Chinese Academy of Sciences Shenyang 110016 China

The influence of pH value of the electrolyte solution on the z.nc electroplating process was studied by means of cyclic voltammetry and chronoamperometry approaches. The results shown that, under this experimental conditions and at high overpotentials, the nucleation of z.nc is instantaneous, and the nuclear densities N increase with the overpotentials. While at low potentials, no distinguished nucleation current can be observed. High pH promotes the deposition either by drifting the initial depositing potential positively, or by increasing the depositing current through the change of the total charge of the adsorption process Qads, i.e., thevstructure of electrochemical double layer.

关键词： z.nc electroplating nucleation growth mechanism

Numerical investigation on the flowfield of “swallowtail” cavity for supersonic mixing enhancement

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Acta Mechanica Sinica 2009年第1期25卷 37-44页

作者： C. Wang z. j.ang z. Hu j. Lu Institute or Mechanics. Chinese Academy of Sciences 100190 Beijing China ReCAPT Gyeongsang National University JinjuKyeongnam 660-701 South Korea

A ＂swallowtail＂ cavity for the supersonic combustor was proposed to serve as an efficient flame holder for scramj.ts by enhancing the mass exchange between the cavity and the main flow. A numerical study on the ＂swallow- tail＂ cavity was conducted by solving the three-dimensional Reynolds-averaged Navier-Stokes equations implemented with a k-e turbulence model in a multi-block mesh. Turbu- lence model and numerical algorithms were validated first, and then test cases were calculated to investigate into the mechanism of cavity flows. Numerical results demonstrated that the certain mass in the supersonic main flow was sucked into the cavity and moved spirally toward the combustor walls. After that, the flow went out of the cavity at its lateral end, and finally was efficiently mixed with the main flow. The comparison between the ＂swallowtail＂ cavity and the conventional one showed that the mass exchanged between the cavity and the main flow was enhanced by the lateral flow that was induced due to the pressure gradient inside the cavity and was driven by the three-dimensional vortex ring generated from the ＂swallowtail＂ cavity structure.

关键词： Supersonic mixing - Flame holder "Swallowtail" cavity - Combustion ignition Numerical simulation

HOT DEFORMATION AND MARTENSITIC TRANSFORMATION BEHAVIORS OF Fe-32%Ni ALLOY

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Acta Metallurgica Sinica(English Letters) 2006年第2期19卷 133-138页

作者： j. Huang z. Xu Cold Rolling Mill Baoshan Iron ＆ Steel Co. Ltd Shanghai 201900 China Key Laboratory for High Temperature Materials and Tests of Ministry of Education Shanghai Jiaotong University Shanghai 200030 China

The Hot deformation and martensitic transformation behaviors of Fe-32%Ni alloy was investigated by measurements of electrical resistance and X-ray diffraction. With the increase in strain, the austenite goes through from the work-hardened to the partial dynamcally re-crystalliz.d and then to the completed dynamically re-crystalliz.d. The martensitic transformation characteristics depend on the austenite states. The work-hardening in small strain is helpful to martensitic transformation due to the low dislocation density and little lattice distortion, while the high dislocation density and severe lattice distortion by the increase in strain will hinder the martensitic nucleation. Once dynamic re-crystalliz.tion （ DRX ） takes place, the martensitic transformation will be enhanced again, which is related to the heterogeneous dynamic substructures. The growing DRX grain can enhance the martensitic nucleation due to the low dislocation density near its grain boundary.

关键词： Fe-32%Ni alloy hot deformation work hardening dynamic re-crystalliz.tion martensitic transformation

Particle shape characterisation and classification using automated microscopy and shape descriptors in batch manufacture of particulate solids

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Particuology 2016年第1期14卷 61-68页

作者： Yang zhang.j.ng j. Liu Lei zhang.j.rge Calderon De Anda Xue z. Wang School of Chemistry and Chemical Engineering South China University of Technology 381 Wushan Road Guangzhou 510641 China School of Bioscience and Bioengineering South China University of Technology Guangzhou Higher Education Mega Centre Panyu District Guangzhou510006 China Institute of Particle Science and Engineering School of Chemical and Process Engineering University of Leeds Leeds I52 9JT UK

It is known that siz. alone, which is often defined as the volume-equivalent diameter, is not sufficient to characteriz. many particulate products. The shape of crystalline products can be as important as siz. in many applications, Traditionally, particulate shape is often defined by several simple descriptors such as the maximum length and the aspect ratio. Although these descriptors are intuitive, they result in a loss of information about the original shape. This paper presents a method to use principal component analysis to derive simple latent shape descriptors from microscope images of particulate products made in batch processes, and the use of these descriptors to identify batch-to-batch variations. Data from batch runs of both a laboratory crystalliser and an industrial crystallisation reactor are analysed using the described approach. Qualitative and quantitative comparisons with the use of traditional shape descriptors that have nhwical meanings and Fourier shape descriptors are also made.

关键词： Batch-to-batch variation Classification Principal components analysis Shape descriptors

Decoloriz.tion of Direct Black 22 by Aspergillus ficuum

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j.urnal of Environmental Sciences 2001年第4期13卷 472-475页

作者： Dong, X.-j. Du, z.-y. Chen, z. Dept. of Biology/Environmental Sci. Wenzhou Normal College Wenzhou 325003 China

The decoloriz.tion of Direct Black 22 by Aspergillus ficuum has been studied. It was found that Aspergillus ficuum could effectively decoloriz. Direct Black 22 especially when grown as pelleted mycelia. Results showed that the media containing Direct Black 22 at 50 mg/L could be decoloriz.d by 98.05% of the initial color in 24 h. The optimum pH and temperature of decoloriz.tion are 4.0 and 33 °C respectively. Aeration was quite beneficial to decoloriz.tion. Medium composition and the concentration of Direct Black 22 could affect the rate of decoloriz.tion. The dye degraded products assayed by UV-visible spectrophotometer and macroscopic observation showed that the decoloriz.tion of Direct Black 22 by mycelial pellets includes two important processes: bioadsorption and biodegradation. The degradation experiment agree with the Michaelis-Menten kinetics equation.

关键词： Bioassay Biodegradation Color Concentration (process) Dyes pH Ultraviolet spectrophotometers

INTERMETALLICS AS SUBSTITUTES FOR SUPERALLOYS

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Acta Metallurgica Sinica(English Letters) 2005年第4期18卷 463-467页

作者： j. zhang.D. Feng z. Y. z.ong High Temperature Materials Division Central Iron and Steel Research Institute Beijing 100081China

The application advances of TiAl, Ti3Al and Ni3Al base aUoys were denumstrated by Central Iron and Steel Research Institute, China. The recent research progresses on improving the reliability of cast TiAI were mainly presented and discussed. The characteristics of the self-oriented lamellar microstructure in cast TiAI were investigated in both as cast and as HlPed states. Based on the mechanical anisotropy of the cast lamellar microstructure, the component specific microstrueture design was proposed for a better performance and reliability of cast TiAl.

关键词： intermetallic application TiAl alloy microstructure design

Development and application of functional gene arrays for microbial community analysis

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中国有色金属学会会刊：英文版 2008年第6期18卷 1319-1327页

作者： z. L. HE j. D. VAN NOSTRAND L.Y. WU j. z. z.OU Institute for Environmental Genomics Department of Botany and Microbiology University of Oklahoma Norman OK 73019 USA

功能的基因标记能关于功能的基因差异和微生物引起的社区的潜在的活动提供重要信息。尽管 microarray 技术成功地被使用了为纯文化学习基因表示，简单、人工的微生物引起的社区，改编如此的一种技术分析复杂微生物引起的社区仍然以设计... 详细信息

功能的基因标记能关于功能的基因差异和微生物引起的社区的潜在的活动提供重要信息。尽管 microarray 技术成功地被使用了为纯文化学习基因表示，简单、人工的微生物引起的社区，改编如此的一种技术分析复杂微生物引起的社区仍然以设计，样品准备，和数据分析提出很多挑战。这个工作集中于功能的基因数组(FGA ) 的开发和应用程序为微生物引起的社区研究指向关键功能的基因标记。一些与 FGA 有关明确地给问题调音，例如 oligonucleotide 探查设计， nucleic 酸抽取和纯化，数据分析，特性，敏感，和量的能力详细被讨论。最近的研究证明了 FGA 能从许多自然环境关于微生物引起的社区提供特定、敏感、潜在地量的信息并且控制生态系统。这种技术被期望革命化微生物引起的社区的分析，并且连接微生物引起的结构到生态系统工作。

关键词：微数列应用函数基因标记微生物种群

Large eddy simulation of turbulent diffusion flame combustion using a conserved scalar methodology

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航空动力学报 2007年第7期22卷 1106-1117页

作者： K. Wang z. Yang j. j. McGuirk Department of Aeronautical and Automotive EngineeringLoughborough University Loughborough Leicestershire LE11 3TU UK

The present paper describes an LES prediction of turbulent diffusion flame combustion in a simplifled axi-symmetric combustor *** calculations are carried out using a well-tested finite volume incompressible LES code which has been modified to handle variable density and reacting *** basic mixture fraction conserved scalar method *** with the chemical state relationships described by fast *** turbulence-chemistry interaction is modelled by a sub-grid PDF method and the PDF is assumed to follow a Beta-function *** LES predictions have been time-averaged over 3.5 flow-through times to generate the mean radial profiles of mixture fraction,product mass fraction,temperature,axial velocity and axial *** agreement of the LES predictions with the experimental data is good for all the above quantities at four different axial positions with largest differences at the first measurement *** LES method also provides information on the unsteady nature of turbulent diffusion *** turbulent reacting flows with large density ratio,it was found necessary to use a relaxation method in order to remove unphysical high-frequency fluctuations and to maintain numerical stability.

关键词：大涡模拟湍流扩散数量方法论弛豫法燃烧理论

ELECTROCHEMICAL STUDY ON THE LOCALIz.D CORROSION OF TWO DIFFERENT TEMPER LY12 ALLOYS

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Acta Metallurgica Sinica(English Letters) 2005年第5期18卷 609-619页

作者： F.H. Cao L. Guo L.j. zhang.z. zhang.j. Q. zhang Department of Chemistry Yuquan Campus Zhejiang University Hangzhou 310027 China State Key Laboratory for Corrosion and Protection of Metals Institute of Metal Research The Chinese Academy of Sciences Shenyang 110016 China

The corrosion behavior of two different aged LY12 alloys in EXCO （234g/L NaCl, 50g/L KNO3 0.1M HNO3） and MIL-H-600 （35g/L NaCl, 5g/L （NH4）2SO4） solutions were studied using electrochemical impedance spectroscopy （EIS） in conj.nction with SEM technique respectively, and the pH variation of the above accelerated corrosion solution during materials corroding was also measured to characteriz. the corrosion processes. At the beginning of corrosion, EIS plots exhibited two capacitive arcs in the high frequency range （Cd） and mediate frequency range （ Cf） originating from the original corroded surface and the newly formed interface respectively, and a low frequency inductive loop due to the relaxation phenomenon of reaction intermediates. In the EXCO,solution, the EIS results showed that once the exfoliation corrosion occurred, the inductive loop disappeared. The results also showed that the exfoliation corrosion susceptibility of state T6 is much higher than that of state T3, but the intergranular corrosion susceptibility has a reverse order. Based on the relationship of EIS results with SEM and metalloscopy morphologies of the corroding substrates and physic-chemical meaning of EIS parameters, an index （Cf/Cd） has been proposed to characteriz. the extent of the localiz.d corrosion, which variation tallies with the real corrosion extent correctly. Meanwhile, good agreement was found between the experimental results and the electrochemical model proposed and, good coherence between the electrochemical features and the distribution type of constituent particles of corroding material was observed.

关键词： electrochemical impedance spectroscope LY12 alloy exfoliation corrosion intergranular corrosion