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Ionic Conduction in Cubic Zirconias at Low Temperatures

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Journal of Materials Science & Technology 2004年第1期20卷 52-54页

作者： yingli YunfaCHEN JianghongGONG InstituteofProcessEngineering ChineseAcademyofSciencesBeijing100080ChinaD~:::--~1NNNQA DepartmentofMaterialsScienceandEngineering TsinghuaUniversityBeijing100084China

The ac conductivities of Y2O3 or CaO-stabilized cubic zirconias were obtained from complex impedance measurements in the temperature range from 373 to 473 K. By analyzing the temperature-dependence of the resultant dc conductivities, it was shown that the activation energies for conduction are lower than those reported previously for the same materials at high temperatures. Comparing the activation energy data with the theoretically estimated values revealed that there may exist a certain, although very small, amount of free oxygen vacancies in the test samples at low temperatures and the conduction in the test samples is a result of the migration of these free oxygen vacancies.

关键词： Ionic conductivity Solid electrolyte Zirconia Activation energy

A Study on Alnico Permanent Magnet Powders Prepared by Atomization

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Journal of Materials Science & Technology 2004年第3期20卷 347-349页

作者： ChangbinSONG BocksooHAN yingli DivisionofMaterialsEngineering KongjuNationalUniversityKongjuKorea DivisionofmechanicalEngineering HanbatNationalUniversityTaejonKorea InstituteofMaterials ShanghaiUniversityShanghai200072China

Alnico powders were prepared by gas atomization process. Composition of the Alnico powders was Fe37.1 A18.2Ni17.6-Co26.6 Cu3.3 Ti7.2 (wt pct) which was the same as that of commercially available Alnico magnets. Averageparticle size of the powders was 119μm. Effects of heat treatment in magnetic field on magnetic properties of thepowders were investigated. The optimum process of heat treatment was found as follows, heated at 870℃ for 1min first, then cooled down to 700℃ at cooling rate 0.3℃/s in magnetic field, and finally aged isothermally for 4 h.Magnetic properties of the Alnico powders were measued and the results were that intrinsic coercivity i_H_c was 1.0kOe and remanence M_r was 36.5 emu/g.

关键词： Gas atomization Alnico magnetic powder

Investigation on a Non-cyanide Plating Process of Ni-P Coating on Magnesium Alloy AZ91D

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Journal of Materials Science & Technology 2005年第3期21卷 301-306页

作者： BonianHU GangYU Jueling yingli LiyuanYE CollegeofChemistryandChemicalEngineering HunanUniversityChangsha410082China CollegeofChemistryandChemicalEngineering HunanUniversityChangsha410082China//HunanCollegeofBuildingMaterialsHengyang421008China

In this research we presented a non-cyanide plating process of Ni-P alloy coating on Mg alloy AZ91D. By applying a new process flow of electroless nickel plating in which zinc coating is used as transition of Ni-P coating on Mg alloy AZ91D, the process of copper transition coating plated in the cyanides bath can be replaced. A new bath composed of NiSO4 was established by orthogonal test. The results show that zinc transition coating can increase the adhesion and protect the Mg alloy substrate from the bath corrosion. The optimal plating bath composition is NiSO4·6H2O 20 g/L, NaH2PO2·H2O20g/L and C6H8O7·H2O 2.5 g/L, and optimal bath acidity and optimal plating temperature are pH 4.0 and 95℃, respectively. The present process flow is composed of ultrasonic cleaning→alkaline cleaning→acid pickling→activation→double immersing zinc→electroplating zinc→electroless nickel plating→passivation treatment. The present non-cyanide process of electroless nickel plating is harmless to our surroundings and Ni-P coating on Mg alloy AZ91D produced by present process possesses good adhesion and corrosion resistance.

关键词： Mg alloy AZ91D Ni-P alloy coating Zinc transition coating Non-cyanide plating process

Chlorine-radical Induced Oxidation of Glyoxal and Glyoxal-S(IV) Adducts in the Aqueous Phase

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Chinese Chemical Letters 2005年第1期16卷 119-122页

作者： yingli YunTANG JiaQiangWANG DepartmentofAppliedChemistry YunnanUniversityKunming650091／／DepartmentofChemistryHongheCollegeMengzi661100 YunnanJiehuaChemGroupCo. Ltd.Kaiyuan661600 DepartmentofAppliedChemistry YunnanUniversityKunming650091

A laser flash photolysis study of the reactivity of Cl˙with glyoxal, glyoxal mono- and dibisulfite adducts, 1-hydroxy-2, 2-diol-ethanesulfonate and 1, 2-dihydroxy-1, 2-ethanedi sulfonate in the aqueous phase was ca... 详细信息

关键词： Chlorine-radical glyoxal glyoxal mono- and dibisulfite adducts aqueous phase rate constants.

Chromatic number and subtrees of graphs

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Frontiers of Mathematics in China 2017年第2期12卷 441-457页

作者： Baogang XU yingli ZHANG Institute of Mathematics School of Mathematical Sciences Nanjing Normal UniversityNanjing 210023 China

Let G and H be two induced subgraph isomorphic to conjectured that, for every tree function, depending only on T graphs. We say that G induces H if G has an H. A. Gyarfas and D. Sumner, independently, T, there exists a function fT, called binding with the property that every graph G with chromatic number fT（ω（G）） induces T. A. Gyarfas, E. Szemeedi and Z. Tuza confirmed the conjecture for all trees of radius two on triangle-free graphs, and H. Kierstead and S. Penrice generalized the approach and the conclusion of A. Gyarfas et al. onto general graphs. A. Scott proved an interesting topological version of this conjecture asserting that for every integer k and every tree T of radius r, every graph G with co（G） ≤ k and sufficient large chromatic number induces a subdivision of T of which each edge is subdivided at most O（14^r-1（r - 1）!） times. We extend the approach of A. Gyarfas and present a binding function for trees obtained by identifying one end of a path and the center of a star. We also improve A. Scott＇s upper bound by modifying his subtree structure and partition technique, and show that for every integer k and every tree T of radius r, every graph with ω（G） ≤ k and sufficient large chromatic number induces a subdivision of T of which each edge is subdivided at most O（6^r-2） times.

关键词： Chromatic number clique number induced tree subdivision

Properties of TiO_2 Thin Films Prepared by Magnetron Sputtering

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Journal of Materials Science & Technology 2002年第2期18卷 101-107页

作者： WenjieZHANG yingli 等 StateLaboratoryforCorrosionandProtection InstittuteofMetalReserachTheChineseAcademyofSciencesShenyang110016China StateLaboratoryforCorrosionandProtection InstittuteofMetalReserachTheChineseAcademy

With rapid progressive application of TiO2 thin films, magnetron sputtering becomes a very interesting method to prepare such multi-functional thin films. This paper focuses on influences of various deposition processes and deposition rate on the structures and properties of TiO2 thin films. Anatase, rutile or amorphous TiO2 films with various crystalline structures and different photocatalytic, optical and electrical properties can be produced by varying sputtering gases, substrate temperature, annealing process, deposition rate and the characteristics of magnetron sputtering. This may in turn affect the functions of TiO2 films in many applications. Furthermore, TiO2-based composites films can overcome many limitations and improve the properties of TiO2 films.

关键词： TiO2 thin film magnetron sputtering deposition process composite film.

A simulation-based emergency force planning method for social security events

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Journal of Systems Engineering and Electronics 2023年第1期34卷 141-148页

作者： YANG Xuesheng WANG yingli GUAN Yong War Studies Institute Academy of Military ScienceBeijing 100091China Strategic Assessments and Consultation Institute Academy of Military ScienceBeijing 100091China

The occurrence of social security events is uncertain, and the distribution characteristics are highly complex due to a variety of external factors, posing challenges to their rapid and effective handling. The scientific and reasonable requirement evaluation of the emergency force to deal with social security events is very urgent. Based on data analysis, this paper uses the neural network, operational research, modelling and simulation to predict and analyze social security events, studies the usage rule of emergency force and deployment algorithm, and conducts simulation experiments to evaluate and compare the different force deployment schemes for selection.

关键词： social security emergency force simulation force deployment

Plasma Nitriding of Low Alloy Sintered Steels

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材料热处理学报 2004年第5期25卷 325-329页

作者： ShivaMansoorzadeh FakhreddinAshrafizadeh Xiao-yingli TomBell DepartmentofMaterialsEngineering IsfahanUniversityofTechnologyIsfahanIran SchoolofEngineering MetallurgyandMaterialsTheUniversityofBirminghamBirminghamUK

Fe-3Cr-0.5Mo-0.3C and Fe-3Cr-l.4Mn-0.5Mo-0.367C sintered alloys were plasma nitrided at different temperatures. Characterization was performed by microhardness measurement, optical microscopy, SEM and XRD. Both materials had similar nitriding case properties. 1.4% manganese did not change the as-sintered microstructure considerably. It was observed that monophase compound layer, formed with increasing temperature. Compound layer thickness increased with increasing temperature while nitriding depth increased up to a level and then decreased. Core softening was more pronounced at higher temperature owing to cementite coarsening.

关键词：等离子渗氮烧结钢锰显微硬度 SEM XRD

Preparation and characterization of ultrafine Fe-Cu-based catalysts for CO hydrogenation

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Journal of Natural Gas Chemistry 2008年第4期17卷 327-331页

作者： Yunlai Su yingli Wang Zhongmin Liu Department of Chemistry Institute of Industrial Catalysis Zhengzhou University Zhengzhou 450052 Henan China Applied Catalysis Laboratory Dalian Institute of Chemical Physics Chinese Academy of Sciences Dalian 116023 Liaoning China

The ultrafine particles of a new style Fe-Cu-based catalysts for CO hydrogenation were prepared by impregnating the organic sol of Fe（OH）3 and Cu（OH）2 onto the activated Al2O3, in which the organic sol of Fe（OH）3 and Cu（OH）2 were prepared in the microemulsion of dodecylbenzenesulfonic acid sodium（S）/n-butanol（A）/toluene（O）/water with V（A）/V（O） = 0.25 and W（A）/W（S） = 1.50. This catalyst was characterized by particle size analysis, XRD and TG. The results of particle size analysis showed that Fe（OH）3 particles with a mean size of 17.1 nm and Cu（OH）2 particles with an average size of 6.65 um were obtained. TG analysis and XRD patterns suggested that 673 K is the optimal calcination temperature. CO hydrogenation produced C＋OH with a high selectivity above 58 wt% by using the ultrafine particles as catalyst, and the total alcohol yield of 0.250 g·ml^-1 ·h^-1 was obtained when the contents of Al2O3 and K were 88.61 wt% and 1.60 wt%, respectively.

关键词： microemulsion conductivity ultrafine Fe-Cu-based catalyst CO hydrogenation