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Surface characteristics of rapidly solidified nickel-based superalloy pow-ders prepared by PREP

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Rare Metals 2003年第4期22卷 309-314页

作者： CHEN Huanming , HU Benfu , and LI Huiying1) school of Materials Science and Engineering, university of Science and Technology Beijing, Beijing 100083,{2.2. school of Physics and Electrical Information Engineering, ningxia university, yinchuan 750021,{2. school of Materials Science and Engineering University of Science and Technology Beijing 北京 100083

The surface microstructure and the surface segregation of FGH 95 nickel-basedsuperalloy powders prepared through plasma rotating electrode processing (PREP) have beeninvestigated by using SEM and AES. The results indicate that the surface microstructure of powderschanges from dendrite into cellular stricture as the particle size of powders decrease, and thepredominant precipitates solidified on the particle surfaces were identified as MC' type carbidesenriched with Nb and Ti. It was also indicated that along with the depth of particle surfaces, thesegregation layer of S, C and O elements are thick, and that of Ti, Cr elements are thin for largesire powders while they are in reverse for median size particles.

关键词： FGH 95 nickel-based superalloy powders surface characteristics microstructure plasma rotating electrode processing

Analysis of Protoscoleces-specific Antigens from Echinococcus Granulosus with Proteomics Combined with Western Blot

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Biomedical and Environmental Sciences 2012年第6期25卷 718-723页

作者： LI Zong Ji and ZHAO WeiDepartment of Medical Genetics and Cell Biology, ningxia Medical university, {2. 750004, ningxia Hui Autonomous Region, china Center of Scientific Technology of ningxia Medical university, {2. 750004, ningxia Hui Autonomous Region, china The medical scientific institute of ningxia, {2. 750004, ningxia Hui Autonomous Region, china Department of Medical Genetics and Cell Biology Ningxia Medical University Yinchuan 750004 Ningxia Hui Autonomous Region China Center of Scientific Technology of ningxia Medical university Yinchuan 750004 Ningxia Hui Autonomous Region China The medical scientific institute of ningxia Yinchuan 750004 Ningxia Hui Autonomous Region China

Objective To establish and optimize the proteomic analysis of protoscoleces-specific antigens from Echinococcus granulosus. To provide a foundation for identifying specific antigens in the soluble proteins of E. granulosus protoscoleces for further research. Methods Brood capsules were collected aseptically from fertile E. granulosus cysts from the livers of an infected patient. The fertile E. granulosus cysts were fractured, and protoscoleces were collected by centrifugation. The soluble proteins of protoscoleces were acquired using the 2. Quant kit according to the manufacturer＇s instructions. We employed two-dimensional electrophoresis （2.DE） combined with immunoblot assay （Western blot） to analyze the soluble components of E. granulosus protoscoleces antigens. The 2.DE and immunoblot maps obtained were analyzed with PDQuest 8.0 image analysis software. Results About 2.3 soluble protein spots were identified with Coomassie-stained gels. Most of the proteins had a molecular weight of 16 000 Da to 117 000 Da, and an isoelectric point value of 3.0 to 10.0. 2.DE immunoblot was conducted and 57 specific antigen spots were observed, among which 2. spots were identified. Conclusion 2.DE combined with Western blot is the key to successful proteomic analysis and presents a new possibility for searching the specific E. granulosus protoscoleces antigens.

关键词： Echinococcus granulosus protoscoleces Proteomics Specific antigen Two-dimensionalelectrophoresis (2.DE) Western blot

Numerical calculation on temperature field of FGH95 alloy droplet during rapid solidification

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Journal of university of Science and Technology Beijing 2003年第3期10卷 51-54页

作者： Huanming Chen and Benfu Hu Materials Science and Engineering school, university of Science and Technology Beijing, Beijing 100083,{2. Physics and Electrical Information Engineering school, ningxia university, yinchuan 750021,{2. Univ Sci & Technol Beijing Sch Mat Sci & Engn Beijing 100083 Peoples R China ningxia Univ Phys & Elect Informat Engn Sch Yinchuan 750021 Peoples R China

The temperature field of FGH95 alloy droplet atomized by plasma rotatingelectrode processing (PREP) during solidification has been calculated through numerical analysisbased on equivalent sensible heat capacity method. And thus the relational curves among temperaturegradient of solid-liquid interface, moving velocity of solid-liquid interface and solid fractionduring solidification have been presented. The results indicate that the relation between averagetemperature gradient of solid-liquid interface and droplet size, and the relation between averagemoving velocity of solid-liquid interface and droplet size can be expressed during solidification.

关键词： FGH95 alloy droplet temperature field numerical calculation

IRC analysis of methanol carbonylation reaction catalyzed by rhodium complex

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Science china Chemistry 2004年第1期47卷 41-49页

作者： HAO Maorong, FENG Wenlin, Jl Yongqiang & LEI MingFaculty of Science, Beijing university of Chemical Engineering, Beijing 10002., china Faculty of Chemical Engineering,{2., yinchuan 750021, china Faculty of Science Beijing University of Chemical Engineering Beijing China Faculty of Chemical Engineering Ningxia University Yinchuan China

In the reaction cycle for methanol carbonylation catalyzed by Rh complex, the structure geometries of the reactant, intermediates, transition states and product of each elemental reaction have been studied by using the energy gradient method at HF/LANL2.Z level, and the changes of their potential profiles have also been calculated. Through IRC analyses of the transition states for each elemental reaction, it is confirmed that the various structure geometries obtained are stationary points on the cycle reaction pathway of methanol carbonylation catalyzed by Rh complex, and the changes are given in energies and structure geometries of the reactant molecules along the reaction pathway of lowest energy. It has been proposed that the geometrical conversions of intermediates play an important role during the cycle reaction. Through analyses of structure geometries, it has been suggested that, in addition to cis- and transstructure exchange linkage of catalysis reactive species, the two pathways, cis- and frans-catalyzed cycle reactions, can also be linked through geometrical conversion of intermediates, of which the activation energy is 49.79 kJ/mol. Moreover, the reductive elimination elemental reaction may be neither c/s-cycle nor trans- one, showing that the cycle reaction can be achieved through various pathways. However different the pathway, the oxidative addition elemental reaction of CH3I is the rate-controlling step.

关键词： rhodium complex catalyst, methanol carbonylation, ab initio method, homogeneous catalysis.

Synthesis and Efficiency of a SphericalMacroporous Epoxy-dicyandiamide ChelateResin for Preconcentrating and SeparatingTrace Au, Hg, Pd and Ru from Samples

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Chemical Research in Chinese Universities 2001年第2期17卷 168-174页

作者： GONG Bo-lin, LI Xue-qiang and WANG Feng-rong (Department of Chemistry, ningxia university, yinchuan 750021,{2.) CHANG Xi-jun (Department of Chemistry, Lanzhou university, Lanzhou 730000,{2.) 宁夏大学宁夏银川 750021 兰州大学甘肃兰州 730000

A novel spherical macroporous epoxy-dicyandiamide chelate resin was synthesized simply and rapidly from epoxy resin and used for the preconcentration and separation of trace amounts of Au (Ⅲ ), Hg (Ⅱ ), Pd (Ⅳ) and Ru (Ⅲ) ions from solution samples. The analyzed ions can be quantitatively concentrated by the resin at a flow rate of 2. 0 mL/min at pH 4, and can also be desorbed with 15 mL of 4 mol/L HCl + 0. 3 g thiourea from the resin column with recoveries of 96. 5%-99. 0%. After the chelate resin was reused for 7 times, the recoveries of these ions were still over 92., and 400-1 000 times of excess of Fe(Ⅲ ), Al(Ⅲ ), Ni( II), Mn( Ⅱ ), Cr (Ⅲ ), Cu ( Ⅱ ), Cd (Ⅱ ) and Pb (Ⅱ ) caused little interference with the determination of these ions by an inductively coupled plasma optical emission spectrometer (ICP-OES ). The capacities of the resin for the analytes are in the range of 0. 35~0. 92.mmol/g. The RSDs of the proposed method are in the range of 1. 1 % ~4. 0% for each kind of the analyzed ions. The recoveries of a standard added in real solution samples are between 96. 5% and 98. 5%, and the results for the analyzed ions in a powder sample are in good agreement with their reported values.

关键词： Concentration Separation Macroporous epoxy-dicyandiamide chelate resin Gold Mercury Palladium and ruthenium.

On　the　Approximation　by　the　Iterates　of　Stancu　Operators　and　Its　Modified　Operators

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Chinese Quarterly Journal of mathematics 1996年第1期11卷 18-25页

作者： Xue yinchuan (Department of mathematics,{2., yinchuan )

This paper discusses the approximation of the class of function W2.and W2.p(1

关键词： Stancu operators iterate Stancu-Kantorovic operators

Microstructure evolution of an Ni-Cr-Co base superalloy heat-treated at 704 and 760℃

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Rare Metals 2003年第3期22卷 169-174页

作者： ZHAOShuangqun XIEXishan HighTemperatureMaterialsResearchlaboratories UniversityofScienceandTechnologyBeijingBeijing100083China；DepartmentofPhysicsNingxiaUniversityYinchuan750021China HighTemperatureMaterialsResearchLaboratories UniversityofScienceandTechnologyBeijingBeiiing100083China

Thermodynamic calculation, SEM (scanning electron microscopy), TEM(transmission electron microscopy), XRD (X-ray diffraction), phase extraction, and chemical analysiswere employed to study the phase stability and phase precipitation in a new Ni-Cr-Co basesuperalloy heat-treated at 704 and 760 ℃ for a long tune. The results show that the precipitates ofthis new alloy heat-treated at standard annealing condition and heat-treated at 704 and 760℃ for atime up to 2.00 h are γ′, MC, M_(2.)C_6, and M_6C, and η phase forms at grain boundaries and inmatrix of samples heat-treated at 760 ℃ as well. The mass fractions of γ′ (+η), MC, M_(2.)C_6,and M_6C in all samples have no large changes with an increase in aging time, but γ′ precipitatesgrow obviously. The γ′-to-η transformation in the samples heat-treated at 760℃ took place withincreasing aging time. The η precipitates form a Widmanstaetten pattern and the γ′ phases haveremelted partly in the samples heat-treated at 760 ℃. The alloy maintains a better microstructuralstability during prolonged aging at 704 ℃, but a worse microstructural stability during prolongedaging at 760 ℃.

关键词： Ni-Cr-Co base superalloy thermodynamic calculation microstructuralstability precipitate phase analysis

Investigation of True Ni^(2.)-Halide Distances in Alkali Halide Lattices

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Journal of Materials Science & Technology 1994年第2期10卷 154-156页

作者： Xuanrong MA(Department of Physics, ningxia university, yinchuan, {2., china)Maolu DU(Institute of Solid State Physics, Sichuan Normal university, Chengdu, 610066, china)(To whom correspondence should be addressed) ningxia Univ Yinchuan China

Using the μKα model of Ni2.-6X- cluster, the true distances between impurity Ni2. cation and halide anion in alkali halide lattices are estimated from the optical spectra data. The results suggest that the true impurity cation- ligand anion distances are close to the sum of ionic radii of the impurity cation and ligand anion but not the cation - anion distance of the perfect lattices in the case of that the ionic radius of host cation is more larger than that of impurity cation

关键词： True Cl Br Investigation of True Ni Halide Distances in Alkali Halide Lattices

TWO ITERATION METHODS FOR SOLVING LINEAR ALGEBRAIC SYSTEMS WITH LOW ORDER MATRIX A AND HIGH ORDER MATRIX B:Y=(AB)Y+Ф

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Journal of Computational mathematics 2000年第4期18卷 419-430页

作者： Shuang-suo Zhao (Depart. of Math. & Computing Engieering, ningxia university, yinchuan, {2., china) Zhang-hua Luo (Depart. of Math. & computer Science, Guangxi Normal university, Guilin, 541004, china) Guo-feng Zhang (Depart. of Math., Lanzhou Univers 宁夏大学宁夏银川 750021 广西师范大学广西桂林 541004 兰州大学甘肃兰州 730000

This paper presents optimum an one-parameter iteration (OOPI) method and a multi-parameter iteration direct (MPID) method for efficiently solving linear algebraic systems with low order matrix A and high order matrix B: Y = (A  B)Y + Φ. On parallel computers (also on serial computer) the former will be efficient, even very efficient under certain conditions, the latter will be universally very efficient.

关键词： System of algebraic equations Iteration method Iteration direct method Solution method for stiff ODEs