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Journal of Advanced Ceramics 2018年第1期7卷 79-87页

作者： Xiaoyan PENG Boping ZHANG Lifeng ZHU Lei ZHAO Ruixiao MA Bo LIU Xiaodong WANG School of Materials Science and Engineering University of Science and Technology Beijing New Metallurgy Hi-Tech Group Co. Ltd. China Iron & Steel Research Institute Group Hebei Key Lab of Optic-Electronic Information and Materials College of Physics Science & Technology Hebei University

(1–x)K_(0.48)Na_(0.56)NbO_3–xBi_(0.5)Li_(0.5)ZrO_3(KNN–x BLZ, x = 0–0.06) lead-free piezoelectric ceramics were prepared by the conventional solid-state sintering method, and their phase structures and electric properties as well as T_C were systematically investigated. The orthorhombic–tetragonal(O–T) two phases were detected in all(1–x)K_(0.48)Na_(0.56)NbO_3–xBi_(0.5)Li_(0.5)ZrO_3 ceramics at 0.01 ≤ x ≤ 0.05. Due to the appropriate ratio between O phase and T phase(CO/C T= 45/55), high piezoelectric properties of d 33= 239 pC/N, k_p= 34%, and P_r = 25.23 μC/cm^2 were obtained at x = 0.04. Moreover, a high T_C = 348 ℃ was also achieved in KNN–x BLZ ceramic at x = 0.04. These results indicate that (1–x)K_(0.48)Na_(0.56)NbO_3–xBi_(0.5)Li_(0.5)ZrO_3 system is a promising candidate for high-temperature piezoelectric devices.

关键词： lead-free piezoelectric ceramics potassium–sodium niobate (KNN) solid-state sintering multi-phase electrical properties

multi-phase ACTIVE CONTOUR MODEL FOR IMAGE SEGMENTATION BASED ON LEVEL SETS

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Transactions of Nanjing University of Aeronautics and Astronautics 2006年第2期23卷 132-137页

作者：郑罡王惠南南京航空航天大学自动化学院

A new multi-phase active contour model is proposed for the image segmentation. It is a generalization of the C-V model with the following characteristics：（1） A key technique, called the technique of painting background （TPBG）, is developed to remove the information of the background, which blocks the detection of weak boundaries in the object; （2） The two-phase level set is applied multiple times for getting the multi-phase segmentation model （n-1 times for the n-phase model, n〉1）; （3） A scaling-based method is introduced to improve the basic model. Experimental results show that the proposed model is effective for detecting weak boundaries.

关键词： level set multi-phase technique of painting background scaling-based method

phase Transition Analysis Based Quality Prediction for multi-phase Batch Processes

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Chinese Journal of Chemical Engineering 2012年第6期20卷 1191-1197页

作者：赵露平赵春晖高福荣 State Key Laboratory of Industrial Control Technology Department of Control Science and EngineeringZhejiang University Department of Chemical and Biomolecular Engineering The Hong Kong University of Science and TechnologyClear Water BayKowloon

Batch processes are usually involved with multiple phases in the time domain and many researches on process monitoring as well as quality prediction have been done using phase information. However, few of them consider phase transitions, though they exit widely in batch processes and have non-ignorable impacts on product qualities. In the present work, a phase-based partial least squares (PLS) method utilizing transition information is proposed to give both online and offline quality predictions. First, batch processes are divided into several phases using regression parameters other than prior process knowledge. Then both steady phases and transitions which have great influences on qualities are identified as critical-to-quality phases using statistical methods. Finally, based on the analysis of different characteristics of transitions and steady phases, an integrated algorithm is developed for quality prediction. The application to an injection molding process shows the effectiveness of the proposed algorithm in comparison with the traditional MPLS method and the phase-based PLS method.

关键词： multi-phase transition partial least squares quality prediction batch process

Near-Iinear elastic deformation behavior of a novel Zr-Ti-Nb-Sn alloy with multi-phase microstructures ofβ,α"andα'phases

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Rare Metals 2023年第5期42卷 1670-1677页

作者： Wen Ma Hao Huang Wang Ding Shun Guo Hai-Xia Liu Xiao-Nong Cheng School of Materials Science and Engineering Jiangsu UniversityZhenjiang212013China China Grinm Group Co. Ltd.Bejing100088China

In this work,a multi-phase Zr-30Ti-7Nb-4Sn alloy with large near-linear elastic deformability was prepared by the solution treatment plus pre-straining(S TP)treatment,and the underlying mechanism accountable for the near-linear elastic deformation was systematically *** was found that the Zr-30Ti-7Nb-4Sn alloy was composed ofβ,α″andα′phases,and numerous dislocations were formed in the alloy specimen after STP *** the retarding effect of high-density dislocations,the stress-induced martensitic(SIM)transformation fromβtoα″phases took place homogeneously and continuously during loading,in conjunction with the occurrence of elastic deformation ofβ,α″andα′*** the entire tensile procedure,no observable phase transformation occurred betweenα′martensite andβ***,the near-linear elastic deformation capability in STP Zr-30Ti-7Nb-4Sn alloy is mainly ascribed to the coupling actions of consecutiveβ→α″SIM transformation and intrinsic elastic deformation ofβ,α″andα′*** experimental results provide a basis for designing and developing novel multi-phase Zr-based alloys that possess large near-linear deformability.

关键词： Zr-based alloy multi-phase Near-linear deformation behavior Martensitic transformation

Heavy metals in a typical city-river-reservoir system of East China:multi-phase distribution,microbial response and ecological risk

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Journal of Environmental Sciences 2022年第2期34卷 343-354页

作者： Jun Yang Mingrui Zhou Kaifeng Yu Karina Yew-Hoong Gin Muhammad Hassan Yiliang He School of Environmental Science and Engineering Shanghai Jiao Tong UniversityShanghai 200240China NUS Environmental Research Institute National University of Singapore1-Create Way#15-02 Create TowerSingapore 138602Singapore China-UK Low Carbon College Shanghai Jiao Tong UniversityShanghai 200240China Department of Civil and Environmental Engineering National University of Singapore1 Engineering Drive 2Singapore 117576Singapore Ecology and Chemical Engineering Department South Ural State UniversityLenin Prospect 76Chelyabinsk 454080Russian Federation

The rapid construction of artificial reservoirs in metropolises has promoted the emergence of city-river-reservoir systems *** study investigated the environmental behaviors and risks of heavy metals in the aquatic environment of a typical system composed of main watersheds in Suzhou and Jinze Reservoir in *** shown that Mn,Zn and Cu were the dominant metals detected in multiple ***,Mn and Zn were mainly presented in exchangeable fraction and exhibited high *** proportion and high mobility of metals were found in suspended particulate matter(SPM),suggesting that SPM can greatly affect metal multi-phase distribution ***,city system(Ci S)exhibited more serious metal pollution and higher ecological risk than river system(Ri S)and reservoir system(Re S)owing to the diverse emission *** S and Re S were regarded as critical pollution source and sink,respectively,while Ri S was a vital transportation *** community in sediments exhibited evident spatial variation and obviously modified by exchangeable metals and *** particular,Bacteroidetes and Firmicutes presented significant positive correlations with most exchangeable *** assessment implied that As,Sb and Ni in water may pose potential carcinogenic risk to human ***,Re S was in a fairly safe *** was the main risk contributor in SPM,while Cu,Zn,Ni and Sb showed moderate risk in ***,Hg,Sb and Ci S were screened out as priority metals and system,*** attention should be paid to these priority issues to promote the sustainable development of the watershed.

关键词： Heavy metal multi-phase Chemical fraction City-river-reservoir system Microbial community

Optimization study of a PEM fuel cell performance using 3D multi-phase computational fluid dynamics model

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2007年第2期8卷 285-300页

作者： AL-BAGHDADI Maher A.R. Sadiq AL-JANABI Haroun A.K.Shahad Department of Mechanical Engineering International Technological University

An optimization study using a comprehensive 3D, multi-phase, non-isothermal model of a PEM （proton exchange membrane） fuel cell that incorporates significant physical processes and key parameters affecting fuel cell performance is presented and discussed in detail. The model accounts for both gas and liquid phase in the same computational domain, and thus allows for the implementation of phase change inside the gas diffusion layers. The model includes the transport of gaseous species, liquid water, protons, energy, and water dissolved in the ion-conducting polymer. Water is assumed to be exchanged among three phases： liquid, vapottr, and dissolved, with equilibrium among these phases being assumed. This model also takes into account convection and diffusion of different species in the channels as well as in the porous gas diffusion layer, heat transfer in the solids as well as in the gases, and electrochemical reactions. The results showed that the present multi-phase model is capable of identifying important parameters for the wetting behaviour of the gas diffusion layers and can be used to identify conditions that might lead to the onset of pore plugging, which has a detrimental effect on the fuel cell performance. This model is used to study the effects of several operating, design, and material parameters on fuel cell performance. Detailed analyses of the fuel cell performance under various operating conditions have been conducted and examined.

关键词： Optimization PEM fuel cell multi-phase Water transport CFD (computational fluid dynamics)

multi-phase helical CT in diagnosis of early hepatocellular carcinoma

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Hepatobiliary & Pancreatic Diseases International 2003年第1期2卷 73-76页

作者： Wen-Ya Liu Yong Jin Run-Huan Rong Xi Ta Xin-Sheng Zhu the CT Department, First Affiliated Hospital of Xinjiang Medical University, Urumqi 830054, China CT Department First Affiliated Hospital of Xinjiang Medical University Urumqi 830054 China. wenyaliu@***

OBJECTIVES: To analyze the characteristics of early hepatocellular carcinoma by using multi-phase helical CT and assess the value of this method. METHODS: multi-phase helical CT findings were reviewed double-blindly by radiologists. RESULTS: Altogether 24 lesions were found in 21 patients. In plain CT, the lesions were seen as hypodense or isodense areas. After contrast enhancement, 87.5% of the lesions showed regular or irregular hyperdense enhancement, whereas 12.5% demonstrated tumor vessels in arterial phase, which became hypodensed or isodensed nodules in portal phase or the hypodensed in delayed phase. The prevalence of density changes showed a hypo-hyper-hypo and hypo-hypo pattern. CONCLUSIONS: multi-phase helical CT could reflect the blood supply of early hepatocelluar carcinoma, and is also convenient for the differential diagnosis of hepatic cavernous angioma, metastatic tumor, hepatic nodulous hyperplasia, and hepatic inflammatory granuloma.

关键词： liver neoplasm spiral CT multi-phase diagnosis contrast enhancement

THE RATE-INDEPENDENT CONSTITUTIVE MODELING FOR POROUS AND multi-phase NANOCRYSTALLINE MATERIALS

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Acta Mechanica Solida Sinica 2007年第1期20卷 13-20页

作者： Zhou Jianqiu Li Yunnling Zhang Zhenzhong Department of Mechanical Engineering Nanjing University of Technology Nanjing 210009 China Department of Material Science and Engineering Nanjing University of Technology Nanjing 210009 China

To determine the time-independent constitutive modeling for porous and multi- phase nanocrystalline materials and understand the effects of grain size and porosity on their mechanical behavior, each phase was treated as a mixture of grain interior and grain bound- ary, and pores were taken as a single phase, then Budiansky＇s self-consistent method was used to calculate the Young＇s modulus of porous, possible multi-phase, nanocrystalline materials, the prediction being in good agreement with the results in the literature. Further, the established method is extended to simulate the constitutive relations of porous and possible multi-phase nanocrystalline materials with small plastic deformation in conjunction with the secant-moduli approach and iso-strain assumption. Comparisons between the experimental grain size and porosity dependent mechanical data and the corresponding predictions using the established model show that it appears to be capable of describing the time-independent mechanical behaviors for porous and multi-phase nanocrystalline materials in a small plastic strain range. Further discussion on the modification factor, the advantages and limitations of the model developed were present.

关键词： nanocrystalline materials constitutive modeling multi-phase porosity plastic deformation

Creating super-tough and strong PA6/ABS blends using multi-phase compatibilizers

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Chinese Chemical Letters 2019年第1期30卷 149-152页

作者： Xianwei Sui Xu-Ming Xie Key Laboratory of Advanced Materials (MOE) Department of Chemical Engineering Tsinghua University

Polyamide/acrylonitrile-butadiene-styrene copolymer(PA/ABS) blends have drawn considerable attention from both academia and industry for their important applications in automotive and electronic areas. Due to poor miscibility of PA and ABS, developing an effective compatibilization strategy has been an urgent challenge to achieve prominent mechanical properties. In this study, we create a set of mechanically enhanced PA6/ABS blends using two multi-monomer melt-grafted compatibilizers, SEBSg-(MAH-co-St) and ABS-g-(MAH-co-St). The dispersed domain size is significantly decreased and meanwhile the unique "soft shell-encapsulating-hard core" structures form in the presence of compatibilizers. The optimum mechanical performances manifest an increase of 36% in tensile strength and an increase of 1300% in impact strength, compared with the neat PA6/ABS binary blend.

关键词： Melt blending multi-phase compatibilizer Morphology Tensile properties Super-tough

Guaranteed Cost Iterative Learning Control for multi-phase Batch Processes

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Journal of Shanghai Jiaotong university(Science) 2018年第6期23卷 811-819页

作者： WANG Limin WANG Runze XIONG Yuting WANG Haosen ZHU Lin ZHANG Ke GAO Furong School of Mathematics and Statistics Hainan Normal UniversityHaikou 571158China College of Sciences Liaoning Shihua UniversityFushun 113001LiaoningChina School of Automation Chongqing UniversityChongqing 400044China Department of Chemical and Biological Engineering Hong Kong University of Science and TechnologyHong KongChina

Batch process is a typical multi-phase process. Due to the interaction between the phases of the batch process, high precision control in a single phase cannot guarantee high precision control of the whole batch process. In order to solve this problem, the guaranteed cost iterative learning control(ILC) of multi-phase batch processes is studied in this paper. Firstly, through introducing the output error, the state error and the extended information, the multi-phase batch process is transformed into an equivalent 2D switched system which has different dimensions. In addition, under the measurable condition, the guaranteed cost iterative learning control law with extended information is designed. The proposed control law ensures not only the stability of the system but also the optimal control performance. Next, in order to study the stability of the system and the minimum running time under the condition of stable running, the multi-Lyapunov function method is used. By means of the average dwell time method, the sufficient conditions ensuring system to be exponentially stable are given in the form of linear matrix inequality(LMI). Finally, the injection molding process is taken as an example to make simulation, which shows the feasibility and effectiveness of the proposed method.

关键词： multi-phase batch process iterative learning control (ILC) average dwell time hybrid guaranteed cost controller