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Crystallization Mechanism of Na_2O-CaO-Al_2O_3-SiO_2-F Glass Containing Cr_2O_3

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International Journal of Minerals,Metallurgy and Materials 1999年第3期13卷 214-218页

作者： Lidong Teng Fuming Wang Wenchao Li(Department of inorganic Materials, shandong institute of Light Industry, jinan 250100, china)(Applied Science School, university of Science and Technology Beijing, Beijing 100083, china) Department of Inorganic Materials Shandong Institute of Light Industry Jinan 250100 China Applied Science School University of Science and Technology Beijing Beijing 100083 China

The effect of Cr2O3 on the nucleation and crystallization of Na2O-CaO-Al2O3-SiO2-F- glass has been investigated by means of ESR(Electron Spin Resonance), SEM(Scanning Electron Microscope), EDS(Energy Dispersive Specrometer) and so on. Computer pattern recognition is applied to optimize the heat-treatment schedules. The experimental results show that the base glass containing more than 1 .5 % (mass fraction) Cr2O3 can be nucleated internally and converted to spheroidal crystal glass materials. The spheroidal crystal consisted of fibrous wollastonite crystals radiating from a center. The residual glass phase filled in the interstices between the fibers and between the spherulites. During heat treatment process, the valence states ofchromium changed from Cr6- to Cr3-, and the Cr-spinel solidsolution [CaCr2O4] precipitated followed this valence change. At the primary stage of crystallization, the Cr-spinel could act as a nucleating center on which the principal or}stalline phase β-CaSiO3 grew epitaxially.

关键词： crystallized glass Na_2O-CaO-Al_2O_3-SiO_2 Cr_2O_3 pattern recognition

Repetitious-Hot-Pressing Technique in Hot-Pressing Process

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Journal of Materials Science & Technology 2003年第5期19卷 486-488页

作者： Shixue SONG, Xing AI, Wei GAO and Jun ZHAO1)School of Mechanical Engineering, shandong university, jinan 250061, china2)School of Science, jinan university, jinan 250022, china School of Mechanical Engineering Shandong University Jinan 250061 China School of Science Jinan University Jinan 250022 China

A new pressing method was proposed for hot-pressing process. Experimental results indicated that the porosity in Al2O3/TiC/ Ni/Mo (hereafter called AI2O3/TiC composite) composite compacts decreases by 6% after adopting this new technique, compared to traditional hot-pressing technique under the same sintering temperature. The flexural strength and Vicker hardness increase from 883 MPa to 980 MPa and from 16 GPa to 21.1 GPa, respectively. A theoretical model was given to analyze the densification mechanism of the composite in the process of repetitious-hot-pressing.

关键词： Hot-pressing sintering Repetitious-hot-pressing sintering Composite

On an attack on RSA with small CRT-exponents

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Science china(Information Sciences) 2010年第8期53卷 1511-1518页

作者： HAN LiDong 1,2 , WANG XiaoYun 3 & XU GuangWu 3,4 1 Key Laboratory of Cryptologic Technology and Information Security, Ministry of Education, shandong university, jinan 250100, china 2 School of Mathematics, shandong university, jinan 250100, china 3 institute for Advanced Study, Tsinghua university, Beijing 100084, china 4 Department of Electrical Engineering and Computer Science, university of Wisconsin-Milwaukee, Milwaukee, WI 53201, USA 1. Key Laboratory of Cryptologic Technology and Information Security Ministry of Education Shandong University Jinan 250100 China2. School of Mathematics Shandong University Jinan 250100 China3. Institute for Advanced Study Tsinghua University Beijing 100084 China4. Department of Electrical Engineering and Computer Science University of Wisconsin-Milwaukee Milwaukee WI 53201 USA

This paper concerns the RSA system with private CRT-exponents. Since Chinese remainder representation provides efficiency in computation, such system is of some practical significance. In this paper, an existing attack to small private CRT-exponents is analyzed. It is indicated that this attack makes nice use of lattice in RSA analysis, but some argument does not hold in general. Several counterexamples are constructed. Refinements and more precise statements of the attack are given.

关键词： RSA CRT cryptanalysis continued fraction lattice reduction

Micromechanical analysis of interaction energy for SMA reinforced composite

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Science china(Technological Sciences) 2009年第3期52卷 610-616页

作者： ZHU YuPing1,2, DUI GuanSuo1 & DUO Liu3 1 institute of Mechanics, Beijing Jiaotong university, Beijing 100044, china 2 Department of Engineering Mechanics, Jiangsu university, Zhenjiang 212013, china 3 State Key Lab of Crystal Materials, shandong university, jinan 250100, china institute of Mechanics Beijing Jiaotong University Beijing 100044 China Department of Engineering Mechanics Jiangsu University Jiangsu Zhenjiang 212013 China State Key Lab of Crystal Materials Shandong University Jinan 250100 China

The energy of the interaction between the matrix and the inclusions in shape memory alloy (SMA) re- inforced composite is one of the most important and complicated parts in thermodynamic constitutive theory. In this paper, the interaction energy is derived based on the classical theory of micromechanics and the thermodynamic theory. The SMA composite is treated as three phases, namely the austenitic phase, the martensite phase and the matrix phase. The interaction among the three phases is analyzed in a way close to the fact. The present expression is used to calculate the interaction energy of a typical SMA composite with attentions paid to understand of the effects of the matrix material, the fiber ge- ometry, and the fiber/matrix volume ratio. It is shown that the method developed in this paper is credible compared with the references. Some useful conclusions are obtained.

关键词： shape memory alloy interaction energy SMA composite micromechanics thermodynamics

Error analysis of the semi-discrete local discontinuous Galerkin method for semiconductor device simulation models

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Science china Mathematics 2010年第12期53卷 3255-3278页

作者： LIU YunXian 1, & SHU Chi-Wang 2 1 School of Mathematics, shandong university, jinan 250100, china 2 Division of Applied Mathematics, Brown university, Providence, RI 02912, USA 1. School of Mathematics Shandong University Jinan 250100 China2. Division of Applied Mathematics Brown University Providence RI 02912 USA

In this paper we continue our effort in Liu-Shu (2004) and Liu-Shu (2007) for developing local discontinuous Galerkin (LDG) finite element methods to discretize moment models in semiconductor device simulations. We consider drift-diffusion (DD) and high-field (HF) models of one-dimensional devices, which involve not only first derivative convection terms but also second derivative diffusion terms, as well as a coupled Poisson potential equation. Error estimates are obtained for both models with smooth solutions. The main technical difficulties in the analysis include the treatment of the inter-element jump terms which arise from the discontinuous nature of the numerical method, the nonlinearity, and the coupling of the models. A simulation is also performed to validate the analysis.

关键词： local discontinuous Galerkin method error estimate semiconductor

Selective Modification of β-Cyclodextrin on the Secondary Side 4:Preparation of Arylated β-Cyclodextrins with a Flexible Chain

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Chinese Chemical Letters 1998年第1期9卷 13-16页

作者： Ai You HAO Lin Hui TONG Min ZHU (College of chemistry, shandong university, jinan 250100)(Lanzhou institute of Chemical Physics, Chinese Academy of Sciences, Lanzhou 730000) shandong Univ Coll Chem Jinan 250100 Peoples R China Chinese Acad Sci Lanzhou Inst Chem Phys Lanzhou 730000 Peoples R China

Mono 3 -deoxy-(N' -benzoyl-ethylenediamino)-β -CD, mono 3 -deoxy-(N' -benzimidoyl -ethylamino)-β-CD, and mono 3 -deoxy-(N' - salicylidene-ethylenediamino)- β -CD, each of which has a flexible chain that bonds the aryl moiety on the secondary side of β-CD, were prepared inthis research. The reaction processes might involve the formation of mono(2, 3 -manno-epoxide )- β -CD as an intermediate in our reaction conditions.

关键词： β-Cyclodextrin Flexible Chain

Influence of Heating Rate on Double Reversible Transformation in CuZnAlMnNi Shape Memory Alloy

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Rare Metals 2001年第2期20卷 117-120页

作者： Yujun Bai, Chengwei Lu, Xiangang Xu, Guili Geng, Longwei Yin (Mechanical Department, shandong university of Science and Technology, jinan 250031, china institute of Materials Science and Engineering, shandong university, jinan 250061, china) shandong Univ Sci & Technol Dept Mech Jinan 250031 Peoples R China shandong Univ Inst Mat Sci & Engn Jinan 250061 Peoples R China

The influence of heating rate on double reversible transformation in CuZnAlMnNi shape memory alloy was investigated by differential scanning calorimetry. It was found that rapid heating inhibits X -->M transformation but is favorable to the reverse martensite transformation, giving rise to the approach of the two transformation peaks. With the decrease of heating rate, the two transformation peaks separate gradually.

关键词： double reversible transformations heating rate CuZnAlMnNi shape memory alloy differential scanning calorimetry

Synthesis and structural characterization of Zn_3N_2 powder

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Science china(Physics,Mechanics & Astronomy) 2005年第2期48卷 201-210页

作者： ZONG Fujian1, MA Honglei1, XUE Chengshan2, ZHUANG Huizhao2, ZHANG Xijian1, MA Jin1, JI Feng1 & XIAO Hongdi1 1. School of Physics and Microelectronics, shandong university, jinan 250100, china 2. institute of Semiconductor, shandong Normal university, jinan 250014, china School of Physics and Microelectronics Shandong University Jinan 250100 China institute of Semiconductor Shandong Normal University Jinan 250014 China

Zinc nitride (Zn3N2) powder has been synthesized through the nitridation reaction of Zn powder with NH3 gas (at the flow rate of 500 ml/min) at the nitridation temperature of 600℃ for 120 min. X-ray diffraction (XRD) indicates that Zn3N2 is cubic in structure with the lattice constant being a = 0.9788 nm. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) show that Zn3N2 powder has surface morphology of various types. X-ray photoelectron spectroscopy (XPS) shows the differences in chemical bonding states between Zn3N2 and ZnO, and confirms the formation of N–Zn bonds. Observation through high resolution transmission electron microscopy (HRTEM) also indicates that the computer simulation of the structure of Zn3N2 is consistent with the structural model put forward by Partin.

关键词： nitridation, Zn3N2 powder, structure, XRD, SEM, TEM, HRTEM, XPS.

DFT and TDDFT investigations on the ground and excited states for polynuclear platinum(II) complexes containing the rigid phenylacetylide ligand

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Science china chemistry 2007年第5期50卷 599-606页

作者： ZHOU Xin1, PAN QingJiang2, LI MingXia1,2, ZHANG HongXing1 & Tang AuChin1 1 State Key Laboratory of theoretical and Computational chemistry, institute of theoretical chemistry, Jilin university, Changchun 130023, china 2 School of chemistry and Materials Science, Heilongjiang university, Harbin 150080, china State Key Laboratory of theoretical and Computational chemistry Institute ofTheoretical ChemistryJilin UniversityChangchun 130023China School of chemistry and MaterialsScience Heilongjiang UniversityHarbin 150080China

We have studied the ground and excited states of the three dendriticpolynuclear Pt(ll) complexes 1-[Cl(PH3)2PtC ident to C]-3,5-[HC ident to C]C6H3 (1),1,3-[CI(PH3)2PtCident to C]2-5-[HC ident to C]C6H3 (2),and 1,3,5-[CI(PH3)2-PtC ident to C]3C6H3 (3),by using theB3LYP and UB3LYP methods,*** approach with the PCM model was performed to predict theemission spectra properties of 1-3 in CH2Cl2 *** first predicted the excited-stategeometries for the three *** the change of the number of Pt(ll) atom,1-3 show thedifferent geometry structures in both the ground and excited states;furthermore,the increase of themetal density from 1 to 3 results in the red shift of the lowest-energy emissions along *** luminescent properties of 1 are somewhat different from those of 2 and *** emissionproperties of 2 and 3 are richer than *** conclusion can give a good support for designing thehigh efficient luminescent materials.

关键词： excited state luminescence dendritic platinum(ll) complexes DFT TDDFT