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Effect of Interfacial Bonding on the Toughening of Al_2O_3/Ni Ceramic Matrix Composites

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Journal of Materials science & Technology 1996年第1期12卷 29-34页

作者： Xudong SUN(dept. of Materials science and Engineering, Northeastern University, Shenyang 110006, China)J.A. Yeomans(dept. of Materials science and Engineering, University of Surrey, Guildford, Surrey GU2 5XH, UK) dept. of Materials science and Engineering Northeastern University Shenyang 110006 China dept. of Materials science and Engineering University of Surrey Guildford Surrey GU2 5XH United Kingdom

The main Iimitation to the toughening of the α-Al2O3/Ni composite is the poor bonding atthe interface. which causes the nickel particles to be pulled-out during crack propagation with-out obvious plastic deformation. A proper control of oxygen content at the Al2O3-Ni interfacecan promote wetting at the intedece, and produce a mechanically interlocked and chemically strengthened intedece, causing most of the nickel particles to be stretched to failure and to expe-rience severe plastic deformation during crack propagation in the composite. Fracture toughnesstesting using a modified double cantilever beam method with in situ observation of crack prop-agation in a scanning electron microscope shows that the composite with the strengthenedinterface has a more desirable R-curve behaviour and a higher fracture toughness value than thenormal composite.

关键词： Al Effect of Interfacial Bonding on the Toughening of Al2O3/Ni Ceramic Matrix Composites Ni

Effect of Wetting and NiAl_2O_4 Spinel Formation on the Bonding between Al_2O_3 and Ni

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Journal of Materials science & Technology 1996年第6期12卷 421-426页

作者： Xudong SUN and J.A. Yeomans (dept. of Materials science and Engineering, University of Surrey Guildford, Surrey GU2 5XH, UK (To whom correspondence should be addressed Present address: dept. of Materials science and Engineering, Northeastern University, dept. of Materials science and Engineering University of Surrey Guildford Surrey GU2 5XH United Kingdom dept. of Materials science and Engineering Northeastern University Shenyang 110006 China

Al2O3-Ni interface formed under vacuum condition is non-wetting and weak. Severe instantaneous intedecial reaction (i.e. wetting) at the Al2O3-Ni interface promoted by oxygen can create a strengthened interface. The NiAl2O4 spinel-Ni intedece is weak and growth of the spinel interphase is detrimental to the Al2O3-Ni intedecial bonding. A proper control of the oxygen partial pressure can achieve wetting while avoiding the existence of spinel at the interface, producing stronger interfaces by both mechanical interlocking and more intimate chemical bonding in an Al2O3-20 vol pct Ni composite.

关键词： NiAl Effect of Wetting and NiAl2O4 Spinel Formation on the Bonding between Al2O3 and Ni IFI Figure

Preparation and characterization of polyimide/silica hybrid films

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Journal of Harbin Institute of Technology(New Series) 2006年第4期13卷 439-443页

作者：张明艳曾恕金董铁权周胜范勇张晓虹雷清泉 dept. of Material science and Engineering Harbin University of science and Technology

A kind of hybrid polyimide films was prepared by synthesizing poly(amic acid)/Silica matrix resin through sol-gel technique and then followed by positing it on a silex glass plate and drying at high temperature. The effect of silica content on the corona-resistant property of the films was studied. The miscibility between the organic and inorganic phases and its effect on the corona-resistant property were investigated with aminopropyltriethoxysilane, which served as a coupling agent, added into the polyimide composite system. The chemical structure and the surface morphology of the films were characterized by FTIR and AFM respectively. The corona-resistant property of the films was tested by a rod-plate electrode. It proved that the corona-resistant property was enhanced with silica content. It also turned out that the improvement of the miscibility between the two phases due to the presence of covalent force as a result of the addition of the coupling agent had, to some extent, effect on the corona-resistant property of the films. Furthermore, a theory on the corona-resistant property was put forward preliminarily.

关键词： polyimide morphology corona-resistant property

Identification and elucidation of anthropogenic source contribution in PM_(10) pollutant: Insight gain from dispersion and receptor models

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Journal of Environmental sciences 2016年第10期28卷 69-78页

作者： Debananda Roy Gurdeep Singh Pankaj Yadav dept. of Environmental science & Engineering Marwadi Education Foundation & Group of Institutions Centre of Mining Environment /Department of Environmental science & Engineering Indian School of Mines dept. of Physics Marwadi Education Foundation & Group of Institutions

Source apportionment study of PM10 （Particulate Matter） in a critically polluted area of Jhafia coalfield, India has been carried out using Dispersion model, Principle Component Analysis （PCA） and Chemical Mass Balance （CMB） techniques. Dispersion model Atmospheric Dispersion Model （AERMOD） was introduced to simplify the complexity of sources in Jharia coalfield. PCA and CMB analysis indicates that monitoring stations near the mining area were mainly affected by the emission from open coal mining and its associated activities such as coal transportation, loading and unloading of coal. Mine fire emission also contributed a considerable amount of particulate matters in monitoring stations. Locations in the city area were mostly affected by vehicular, Liquid Petroleum Gas （LPG）＆ Diesel Generator （DG） set emissions, residential, and commercial activities. The experimental data sampling and their analysis could aid understanding how dispersion based model technique along with receptor model based concept can be strategically used for quantitative analysis of Natural and Anthropogenic sources of PM10.

关键词： Source apportionment PM10 PCAReceptor modelDispersion modelJharia coalfield

Leader-following coordination of multi-agent systems with information feedback

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Journal of Systems Engineering and Electronics 2009年第4期20卷 823-828页

作者： Wang Dongmei Fang Huajing dept. of Control science and Engineering Huazhong Univ of Science and Technology Wuhan 430074 P. R. China

Based on the strategy of information feedback from followers to the leader, flocking control of a group of agents with a leader is studied. The leader tracks a pre-defined trajectory and at the same time the leader uses the feedback information from followers to the leader to modify its motion. The advantage of this control scheme is that it reduces the tracking errors and improves the robustness of the team cohesion to followers＇ faults. The results of simulation are provided to illustrate that information feedback can improve the performance of the system.

关键词： multi-agent system leader-following flocking control information feedback.

Notes on the Design of an Integrated Object-Oriented DBMS Family

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Journal of Computer science & Technology 1991年第4期6卷 389-394页

作者：商陆军许立辉 Computer science dept. Nanjing University Nanjing 210008 Computer science dept. Tianjing University Tianjin 300072

This paper summarizes the design and implementation notes of the CodDdBase system,which is a corn binative distributed database management system family based on an integrated object *** is implemented in CLUSTER 86,a general purposed object-oriented programming language designed by the *** CoDdBase environment is actually a part of the CLUSTER 86 programming environment,which offers various object-based models,supplies miscellaneous building blocks for constructing different distributed DBMS's,and provides integrated programming tools to develop new ways and new models in response to changing application needs.

关键词： In Notes on the Design of an Integrated Object-Oriented DBMS Family Design

Effects of Hyperfine and Dopant Cation Interactions on theDC-Electrical Conductivity of MnZn Ferrites

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Journal of Materials science & Technology 1997年第6期13卷 467-470页

作者： M.M.Abou Sekkina(Chem. dept., Faculty of science, Tanta University, Tanta, Egypt)A.M.El-Sayed(Inorganic Chemistry dept., National Research Centre, Dokki, Cairo, Egypt) Chem. dept. Faculty of Science Tanta University Tanta Egypt Inorganic Chemistry dept. National Research Centre Dokki Cairo Egypt

Samples of undoped, and CuO, CaO, Al2O3 as well as V2O5 doped MnZn ferrite were prepared using standard ceramic method. The X-ray diffraction results for the base and doped ferrite samples show a single phase with spinel cubic structure. The Mossbauer spectrum of the base sample indicates line broadening and overlapping due to relaxation of magnetic dipoles. The temperature dependence of DC-electrical conductivity has been discussed on the basis of electronic conduction (electron hopping) and ionic conduction mechanism.

关键词： Effects of Hyperfine and Dopant Cation Interactions on theDC-Electrical Conductivity of MnZn Ferrites

Research on robust fault-tolerant control for networked control system with packet dropout

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Journal of Systems Engineering and Electronics 2007年第1期18卷 76-82页

作者： Huo Zhihong Fang Huajing dept. of Control science and Engineering Huazhong Univ. of Science and Technology Wuhan 430074 P.R. China

A kind of networked control system with network-induced delay and packet dropout, modeled on asynchronous dynamical systems was tested, and the integrity design of the networked control system with sensors failures and actuators failures was analyzed using hybrid systems technique based on the robust fault-tolerant control theory. The parametric expression of controller is given based on the feasible solution of linear matrix inequality. The simulation results are provided on the basis of detailed theoretical analysis, which further demonstrate the validity of the proposed schema.

关键词： Networked control system (NCS) Fault-tolerant control (FTC) Asynchronous dynamical systems (ADS) Integrity design Packet dropout Time delay

Refinement and Transformation from Z Specification to C+ +

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Journal of Donghua University(English Edition) 2001年第4期18卷 97-102页

作者： Zhang Xiaoying(张晓莺) Chen Jiaxun(陈家训) dept. of Computer science and Engineering Dong Hua University Shanghai 200051 Dept. of Computer Science and Engineering Dong Hua University Shanghai 200051

As a kind of formal specification language, Z has gained a position in the field of software development, but there is still no standard way of transforming Z specification into executable code that is promising in increasing the quality, reusability and maintainability of *** the automatic programming model of software engineering, through the analysis for Z specification language, a feasible semi-automatic way of refinement and transformation is proposed, and the correctness of the procedure is also discussed.

关键词： Z specification refinement transformation C + + Class template Function template