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Journal of Materials Science & Technology 1996年第6期12卷 439-444页

作者： Chuanfang YANG and Jiayong CHEN (institute of Chemical Metallurgy, chinese academy of sciences, beijing 100080,{3.)(To whom correspondence should be addressed) institute of Chemical Metallurgy Chinese Academy of Sciences Beijing 100080 China

Zr(IV) was extracted by tri-n-butyl phosphate in kerosene from concentrated nitric acid solutions and the formation of the third phase during extraction was experimentally investigated. Zirconia powders were prepared by using the loaded organic phase as the bulk solution precipitated with aqueous ammonia or NaOH solution. The powder prepared was characterized with TEM, XRD,EDAX and TG-DTA. Effects of some conditions on powder preparation were studied and it was shown that nanosized particles could be obtained from this extraction system but conditions should be carefully controlled for powder purity and particle size.

关键词： Zirconia

Microstructure of Pd_(77.5)Au_6Si_(16.5) Alloy Droplet Solidified in a Drop Tube Process

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Journal of Materials Science & Technology 1996年第5期12卷 385-388页

作者： Liling SUN Qi WU Liwei SUN and Wenkui WANG (institute of Physics, chinese academy of sciences, beijing 100080,{3.) institute of Physics Chinese Academy of Sciences Beijing 100080 China

The microstructure development of Pd77.5Au6Si16.5 alloy droplet solidified in a drop tube process was studied. It was found that two distinct microstructures, i.e. (Pd,Au)3.i primary phase and Pd+(Pd,Au)3.i eutectic can be obtained when the droplet diameter is within the range between 2.3.0.4 mm. The morpologies of the (Pd,Au)3.i developed from dendrite trunk-like with single branching only into dendrite cluster-like with ternary branching with the decrease of the droplet diameter. When the droplet diameter is about 0.25 mm, the primary phase (Pd,Au)3.i almost disappears and the microstructure mainly shows Pd+(Pd,Au)3.i eutectic. The morphology of the eutectic transforms from fiber-like to plate-like with the decrease of the droplet diameter in the range between 2.3.0.25 mm. When the droplet diameter is about 0.19 mm, the microstructure is only the single phase of Pd solid solution

关键词： Microstructure of Pd Au6Si Alloy Droplet Solidified in a Drop Tube Process

Integrated precise orbit determination of Shenzhou IV unmanned spacecraft

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Science china(Technological sciences) 2004年第5期47卷 518-525页

作者： L Congmin1,2, GU Yidong3. LIN Baojun3.& GUO Jiong3.1. Center for Space Science and Applied Research, chinese academy of sciences, beijing 100080, china 2. Graduate School of the chinese academy of sciences, beijing 10003., china 3. General Establishment of Space Science and Application, chinese academy of sciences, beijing 100080, china Correspondence should be addressed to L Congmin General Establishment of Space Science and Application Chinese Academy of Sciences

Considering the characteristic orbit of Shenzhou IV spacecraft and the advantages and disadvantages of several types of domestic orbit measurements, a scheme of IPOD is determined, which uses GPS, SLR and USB observation data jointly plus precise ionosphere corrections to GPS observation data. IPOD system and mathematic models of OD are introduced. The results of different joint OD are analyzed using true observation data, and show that radial accuracy is better than 2 m.

关键词： Shenzhou IV unmanned spacecraft integrated precise orbit determination GPS SLR USB.

THE PRIMAL-DUAL POTENTIAL REDUCTION ALGORITHM FOR POSITIVE SEMI-DEFINITE PROGRAMMING

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Journal of Computational Mathematics 2003年第3期21卷 339-346页

作者： Si-ming Huang(institute of Policy and Management, academy of Mathematics and System sciences,{3., beijing 100080, china) institute of Policy and Management Academy of Mathematics and System Sciences Chinese Academy of Sciences 北京 100080

In this paper we introduce a primal-dual potential reduction algorithm for positive semi-definite programming. Using the symetric preserving scalings for both primal and dual interior matrices, we can construct an algorithm which is very similar to the primal-dual potential reduction algorithm of Huang and Kortanek [6] for linear programming. The complexity of the algorithm is either O(nlog(X0 · S0/ε) or O(nlog(X0· S0/ε) depends on the value of ρ in the primal-dual potential function, where X0 and S0 is the initial interior matrices of the positive semi-definite programming.

关键词： Positive semi-definite programming Potential reduction algorithms Complexity.

Fiducial inference in the pivotal family of distributions

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Science china Mathematics 2006年第3期49卷 410-432页

作者： XU Xingzhong & LI Guoying Department of Mathematics, beijing institute of Technology, beijing 100081,{3. academy of Mathematics and Systems Science, chinese academy of sciences, beijing 100080,{3. Department of Mathematics Beijing Institute of Technology Beijing China academy of Mathematics and Systems Science Chinese Academy of Sciences Beijing China

In this paper a family, called the pivotal family, of distributions is considered.A pivotal family is determined by a generalized pivotal model. Analytical results show that a great many parametric families of distributions are pivotal. In a pivotal family of distributions a general method of deriving fiducial distributions of parameters is proposed. In the method a fiducial model plays an important role. A fiducial model is a function of a random variable with a known distribution, called the pivotal random element, when the observation of a statistic is *** method of this paper includes some other methods of deriving fiducial distributions. Specially the first fiducial distribution given by Fisher can be derived by the method. For the monotone likelihood ratio family of distributions, which is a pivotal family, the fiducial distributions have a frequentist property in the Neyman-Pearson view. Fiducial distributions of regular parametric functions also have the above frequentist property. Some advantages of the fiducial inference are exhibited in four applications of the fiducial distribution. Many examples are given, in which the fiducial distributions cannot be derived by the existing methods.

关键词： confidence bounds, fiducial distributions, fiducial model, frequentist prop-erty, generalized pivotal model, pivotal family of distributions, testing hypotheses.

PREPARATION OF BISPHENOL A EPOXY RESIN WATERBORNE DISPERSIONS BY THE PHASE INVERSION EMULSIFICATION TECHNIQUE

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chinese Journal of Polymer Science 2000年第1期18卷 33-38页

作者： Zhen-zhong Yang De-lu Zhao Polymer Physics Laboratory, institute of Chemistry, chinese academy of sciences, beijing 100080,{3. 中科院化学所高分子物理及化学国家重点实验室北京

The phase inversion emulsification technique (PIET) is an effective physical method for preparing waterborne dispersions of polymer resins. Some results concerning the preparation of bisphenol A epoxy resin waterborne dispersions by PIET in our laboratory were summarized. Electrical properties, rheological behavior and morphological evolution during phase inversion progress were systematically characterized. The effects of the emulsifier concentration and emulsification temperature on phase inversion progress and the structural features of the waterborne particles were studied as well. The deformation and break up of water drops in a shear field were analyzed in terms of micro-theology, while the interaction and coalescence dynamics of water drops were discussed in terms of DLVO theory and Smoluchowski effective collision theory, respectively. Based on the experimental results and theoretical analysis, a physical model of phase inversion progress was suggested, by which the effects of the parameters on phase inversion progress and the structural features of the waterborne particles were interpreted and predicted.

关键词： phase inversion emulsification waterborne dispersions epoxy resin mechanism physical model

SILICA-SUPPORTED NICKEL AND ZIRCONIUM CATALYSTS FOR BRANCHED POLYETHYLENE

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chinese Journal of Polymer Science 2003年第4期21卷 453-458页

作者：孙文华 State Key Laboratory of Engineering Plastics The Center for Molecular sciences institute of Chemistry chinese {3. of sciences beijing 100080 china State Key Laboratory of Engineering Plastics The Center for Molecular Sciences Institute of Chemistry Chinese Academy of Sciences Beijing 100080 China

8-Aminoquinoline nickel dichloride and bis(cyclopentadienyl)zirconium dichloride (Cp_2ZrCl_2) were supportedsimultaneously on silica to produce branched polyethylene successfully by combined polymerization. The supportedpolymerization results showed that the molecular weight of polyethylene increased while the molecular weight distributionbecame wider and the molecular chains of oligomers remaning in the final solution became shorter as compared to theoligomers obtained in polymerization processes with pure 8-aminoquinoline nickel dichloride catalysis, as well as theCp_2ZrCl_2 and nickel combination system. With decreasing amount of Ni catalyst in the supported catalyst, the molecular chains of oligomers in the resulting solution became shorter, while α-olefin selectivity increased.

关键词： 8-Aminoquinoline nickel dichloride, Cp_2ZrCl_2 Silica supported catalysts Branched polyethylene

A quasi-local mass for 2-spheres with negative Gauss curvature

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Science china Mathematics 2008年第9期51卷 1644-1650页

作者： ZHANG Xiao institute of Mathematics, academy of Mathematics and Systems Science, chinese academy of sciences,{3., china institute of Mathematics Academy of Mathematics and Systems Science Chinese Academy of Sciences Beijing China

We extend our previous definition of quasi-local mass to 2-spheres whose Gauss curvature is negative, and prove its positivity.

关键词： general relativity quasi-local mass positivity 53.27 53.50 83.60

NUMERICAL SOLUTION OF THE UNSTEADYINCOMPRESSIBLE NAVIER-STOKES EQUATIONS ON THECURVILINEAR HALF-STAGGERED MESHNUMERICAL SOLUTION OF THE UNSTEADYINCOMPRESSIBLE NAVIER-STOKES EQUATIONS ON THECURVILINEAR HALF-STAGGERED MESH

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Journal of Computational Mathematics 2000年第5期18卷 521-540页

作者： Lan-chieh Huang (institute of Computational Mathematics and Scientific/Engineering Computing, chinese academy of sciences, beijing 100080,{3.) 中科院计算数学与科学工程计算所北京 100080

In this paper, the Crank-Nicholson + component-consistent pressure correction method for the numerical solution of the unsteady incompressible Navier-Stokes equation of [1] on the rectangular half-Staggered mesh has been extended to the curvilinear half-Staggered mesh. The discrete projection, both for the projection step in the solution procedure and for the related differential-algebraic equations, has been carefully studied and verified. It is proved that the proposed method is also unconditionally (in t) nonlinearly stable on the curvilinear mesh, provided the mesh is not too skewed. It is seen that for problems with an outflow boundary, the half-Staggered mesh is especially advantageous. Results of preliminary numerical experiments support these claims.

关键词： Unsteady incompressible Navier-Stokes equations Curvilinear half- staggered mesh Discrete projection.

ENHANCING GOLD EXTRACTION FROM COPPER BEARING ORES

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中国有色金属学会会刊：英文版 1995年第3期5卷 25-28页

作者： Deng, Tong Ma, Yun(institute of Chemical Metallurgy,chinese academy of {3., beijing 100080) chinese Acad of sciences Beijing China

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关键词： Copper Gold Ammoniacal cyanidation