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TRANSFORMATION OF UPPER BAINITE IN 55SiMnMo STEEL DURING TEMPERING

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Acta Metallurgica Sinica(English Letters) 1990年第2期3卷 138-141页

作者： LIAO Yuyan LIU Zhengyi south china university of technology,Guangzhou,china LIAO Yuyan Lecturer,Dept.of Mechanical Engineering No.2,south china university of technology,Guangzhou 510641,china

The transformation of upper bainite of normalized 55SiMnMo steel during tempering has been studied by optical microscopy,X-ray diffraction,transmission electron microscopy and differential scanning *** plate surface is parallel to ferrite{110}and is the coherent interface for α and γ,the crystallographic relationship is(111)_γ,∥(011)_α.The small plate surface of Fe_3C precipitated during tempering is parallel to(100).The strengthening mechanism for carbon-rich austenite in normalized condition is primarily uniform solid so- lution hardening,however,in the tempered state,it is strengthened chiefly by non-uniform one.

关键词： SiMnMo steel bainite transformation

Decentralized　Variable　Structure　Control　of　Complex　Giant　Singular　Uncertainty　Systems

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Journal of Systems Engineering and Electronics 1996年第1期7卷 23-34页

作者： Wen Xiangcai&Liu Yongqing (Department of Automation, south china university of technology Guangzhou, 510641, P. R. china.) Department of Automation South China University of Technology Guangzhou 510641 P. R. China

This paper, at the first time, considers the problem of decentralized variable structure control of complex giant singular uncertainty systems by using the property of diagonally dominant matrix and Frobenius-Person theorem. The splendid selection of switching manifold for each subsystem makes the design relatively straightforward and can be easily realized. An illustrate example is given.

关键词： Complex giant singular uncertainty systems Multiple input interconnected Decentralized variable structure control Sliding mode Completely controllable.

Characterization of bioactive ceramic coatings prepared on titanium implants by micro-arc oxidation

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Rare Metals 2006年第1期25卷 84-89页

作者： WANG Yingjun NAN Kaihui CHEN Xiaofeng NING Chengyun WANG lingyu ZHAO Naru The Key Laboratory for Specially Functional Materials and Advanced Manufacturing technology Ministry of Education South China University of Technology Guangzhou 510640 China Biomaterials Research Center College of Materials Science and Engineering South China University of Technology Guangzhou 510640 China

Micro-arc oxidation （MAO） is an enhanced chemical technology in an electrolyte medium to obtain coating structures on valve-metal surfaces. Titanium oxide films obtained by MAO in the sodium phosphate electrolyte were investigated. The films were composed mainly of TiO2 phases in the form of anatase and mille and enriched with Na and P elements at the surface. Their apafite-inducing ability was evaluated in a simulated body fluid （SBF）. When immersing in SBF for over 30 d, a preferential carbonated-hydroxyapatite was formed on the surfaces of the films, which suggests that the MAO-treated titanium has a promising positive biological response.

关键词： ceramic coatings micro-arc oxidation bio-mimetic mineralization carbonated-hydroxyapatite

Effect of Addition of Sodium Dodecyl Sulfite on Physical Properties of Wheat Gluten Films

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Journal of Wuhan university of technology(Materials Science) 2005年第2期20卷 15-19页

作者：曾瑜薇 School of Foreign Language Hubei University of TechnologyWuhan 430068China Assoc.Prof

Films were made from the wheat glutens treated with 5%,10%,15%,20%,25% and 30%(wt% of gluten) of sodium dodecyl sulfite (SDS) in order to improve the properties of the films. Glycerol was used as a *** addition of SDS in wheat glutens prior to forming films significantly increased the elongation at break(E) (P<0.05) and reduced notably the water vapor permeability(WVP) (P<0.05). In contrast,a decrease in the tensile strength(TS) of the films from gluten containing-SDS was ***,a significant decrease in P_(O_2) and P_(CO_2) of films from gluten treated with SDS was noticed. Although SDS-treated gluten film was slightly more yellow and darker than control one, it was not visually detrimental. It is indicated that the treatment with SDS prior to forming films greatly enhances the mechanical properties of wheat gluten *** obivous improvement in water vapor permeability and extensibility of gluten films means that the use of SDS is a potential choice for improving properties of gluten films. The edible film was used to preserve tomatoes. The experimental results show that the shelf life of tomatoes coated with the edible film is extended, and the nutritional quality is kept well.

关键词： wheat gluten sodium dodecyl sulfite (SDS) tensile strength (TS) elongation at break(E) water vapor permeability(WVP) tomato preservation

EFFECT OF Zr ON PHASE TRANSFORMATION IN Cu-Zn-Al SHAPE MEMORY ALLOYS

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Acta Metallurgica Sinica(English Letters) 1990年第2期3卷 93-98页

作者： XIAO Jichuang FANG Jianneng south china university of technology,Guangzhou,china XIAO Jichuang Associate Professor,Dept.of Mechanical Engineering No.2,south china university of technology,Guangzhou 510641,china

An investigation was made of the influence of Zr additive on the high temperature phase trans- formations,martensitic forward/reverse transformations,and shape memory effect of Cu-Zn-Al base alloys by means of differential scanning calorimetry(DSC),X-ray diffraction and *** was found that an addition of 0.35 wt-% Zn could effectively inhibit the precipitation of α and γ phases and hence promote the order-martensitic transformations β_2→DO_3→18RM,thus resulting in a minimum activation energy of the martensitic trans- formation and narrow temperature ranges(M_s-M_f)and(A_s-A_f);the alloy so obtained pos- sessed smooth and mobile martensite intervariant interfaces,therefore showing the best shape memory effect.

关键词： Cu-Zn-Al alloy Zr differential scanning calorimetry phase transformation

Effects of NaNbO_3-Co_2O_3 Co-additive on the Properties of PZN-PZT Ceramics

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Journal of Wuhan university of technology(Materials Science) 2007年第4期22卷 722-724页

作者：邓毅华 College of Material Science and Engineering South China University of Technology Department of Electronic Science and technology Huazhong University of Science and TechnologyWuhan 430074China

NaNbO3-Co2O3 co-added PZN-PZT （PZCNNT） ceramics were prepared using conventional solid state reaction. The piezoelectric and dielectric properties were measured. The experimental results show that the addition of 0.3mo1% Co2O3 leads to low dielectric loss （tgδ） in PZCNNT ceramics and the proper addition of NaNbO3 not only improves piezoelectric properties but also decreases intensively dielectric loss and mechanical loss. The optimal ceramic having d33=310 pC/N, kp=0.59, εr=985, tgδ=0.0034, Qm=1380 was obtained.

关键词： PZN-PZT piezoelectric constant dielectric constant dielectric loss

Coexisting hidden attractors in a 4D segmented disc dynamo with one stable equilibrium or a line equilibrium

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Chinese Physics B 2017年第8期26卷 14-23页

作者：鲍江宏陈丹丹 School of Mathematics South China University of TechnologyGuangzhou 510641China

This paper introduces a four-dimensional （4D） segmented disc dynamo which possesses coexisting hidden attractors with one stable equilibrium or a line equilibrium when parameters vary. In addition, by choosing an appropriate bifurcation parameter, the paper proves that Hopf bifurcation and pitchfork bifurcation occur in the system. The ultimate bound is also estimated. Some numerical investigations are also exploited to demonstrate and visualize the corresponding theoretical results.

关键词： coexisting hidden attractors 4D segmented disc dynamo pitchfork bifurcation Hopf bifurcation,ultimate bound estimation

Synthesis and Photocatalytic Property of the ZrO_2/TiO_2 Pillared Laponite

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Journal of Wuhan university of technology(Materials Science) 2011年第5期26卷 852-856页

作者：林英光 College of Materials Science and Engineering South China University of Technology

The ZrO2/TiO2 pillared laponite （Ti-Zr-lap） photocatalysts were prepared with intercalation reaction by supercritical fluid drying （SCFD）,and characterized by XRD,TEM,SEM and BET surface area analysis,and the photocatalytic properties of Ti-Zr-lap were investigated by degradation of azo dye acid red B （ARB）.The results showed that the ZrO2/TiO2 pillared structures in laponite could be formed,with the mass fraction of （Zr4＋＋Ti4＋）/laponite （Xm） increasing,the basal spacing and the BET surface area of Ti-Zr-lap significantly *** Ti-Zr-lap used as photocatalyst had the advantages of stable and porous layered structure,large surface area with the anatase type *** with the Ti-Zr-lap dried by air drying,the Ti-Zr-lap dried by SCFD showed better photocatalytic property which was very close to that of P25 *** the Ti-Zr-lap as photocatalyst with the optimum Xm of 0.16 and the calcination temperature of 500 ℃,under the conditions of the initial concentration of ARB 20 mg/L,photocatalyst concentration of 1.5 g/L and irradiation time 60 min,the decoloring rate of ARB could achieve 98.3%,indicating that the Ti-Zr-lap had excellent photocatalytic property.

关键词： ZrO2/TiO2 pillared laponite photocatalytic property intercalation reaction supercritical fluid drying

Direct gray-scale extraction of topographic features for vein recognition

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Science china(Information Sciences) 2010年第10期53卷 2062-2074页

作者： KANG WenXiong 1, LI HuaSong 2 & DENG FeiQi 1 1 College of Automation Science and Engineering, south china university of technology, Guangzhou 510640, china 2 School of Information Engineering, Wuyi university, Jiangmen 529000, china 1. College of Automation Science and Engineering South China University of Technology Guangzhou 510640 China2. School of Information Engineering Wuyi University Jiangmen 529000 China

Binarization processing is a key step in most vein pattern recognition, but may create flaws such as leakage of some feature information. In order to overcome this problem, a new approach is explored in this paper which can extract topographic features directly from gray-scale vein images without binarization processing. First, an extreme graph of directional fields (EGDF) is calculated according to neighborhood information of every pixel, and then the intravenous main ridge of the image can be separated step by step from EGDF with the defined constraint template sets. After that, the sub-ridge is extracted from end points of the main ridge in range constraint image with the tracing method of maximal neighboring point. According to contrast experiment the proposed method is better than the traditional processing (performing binarization first and then skeletonization), in that it can overcome the problem that some separate vein lines are extracted incorrectly, and it can avoid extracting two neighboring vein lines as one ridge. As such, the proposed method is an effective way to extract topographic features for vein recognition

关键词： vein recognition feature extraction directional fields