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Science China(Technological Sciences) 2009年第2期52卷 324-331页

作者： WANG WeiDa Research Laboratory for Conservation & Archaeology, shanghai Museum, shanghai 200050, China Research Laboratory for Conservation & Archaeology Shanghai Museum Shanghai China

The pre-dose technique is important for thermoluminescence (TL) dating of porcelain. The principle of pre-dose dating is based on two characteristics: thermal activation and radiation quenching of the porcelain. Based on these principles, two measurement methods, "the activation method" and "the quenching method", respectively, have been developed for evaluation of the porcelain paleodose. The paleodose values obtained are the same for the ages in the range of 100―1000 a BP for porcelains measured by these two methods. But for dating at lower age limits (less than 100 a BP), the activation method is more accurate; conversely, at higher age limits (greater than 1000 a BP) the quenching method is more accurate. In addition, two specific calculating methods are described for a few porce-lains having anomalous activation and quenching characteristics that make these two methods invalid.

关键词： porcelain thermoluminescence dating pre-dose technique thermal activation radiation quenching

Kinetic Process and Conductivity of Ag^+ Ion Exchange for Polycrystalline Na-β"-Al_2O_3

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Journal of Materials Science & Technology 1996年第4期12卷 315-317页

作者： Jianhua YANG(shanghai Institute of Ceramics, Chinese Academy of Scieoces, shanghai 200050, China) shanghai Institute of Ceramics Chinese Academy of Sciences Shanghai 200050 China

This paper reports the kinetic process of Ag ion exchange for the polycrystalline Na-β'-*** interdiffusion coefficients in the process of Ag+ and Na+ ion exchange have been calculated with an 'one dimensional double side diffusion model'. Microstructures of the samples were observed and analysed by XRD, EMPA, SEM. The results of the conductivity measurements for samples with Na+, Ag+ and Na+-Ag+ mobile ions are presented and explained

关键词： Kinetic Process and Conductivity of Ag Ion Exchange for Polycrystalline Na Al2O3

Study and progress of the thermoluminescence dating of the ancient pottery and porcelain

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Science China(Technological Sciences) 2009年第6期52卷 1613-1640页

作者： WANG WeiDa Research Laboratory for Conservation & Archaeology,shanghai Museum,shanghai 200050,China Research Laboratory for Conservation & Archaeology Shanghai Museum Shanghai China

Two standard methods,the "fine-grain technique" and the "quartz inclusion technique",and a new method,the pre-dose saturation exponential technique in thermoluminescence(TL)dating of ancient pottery and porcelain were reviewed,especially for the measurement of the paleodose and the annual *** two standard methods have been acknowledged in domain of TL dating and are used widely for age determination in archaeology and *** a dating tool the TL technique has been of great success in authentication of ancient ceramic art ***,a few complicated factors limit the precision and accuracy in age *** complicated factors are analyzed and ***,although ceramic TL dating can in general solve the problem of authentication of ancient ceramics,there are still complexities that require further research and study.

关键词： thermoluminescence dating pottery porcelain

Evaluation for the paleodose in thermoluminescence dating of porcelain

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Science China(Technological Sciences) 2008年第3期51卷 260-267页

作者： WANG WeiDa Research Laboratory for Conservation & Archaeology, shanghai Museum, shanghai 200050, China Research Laboratory for Conservation & Archaeology Shanghai Museum Shanghai China

Sources, components and calibration of paleodose were studied for proper evalua- tion of the paleodose of porcelain in thermoluminescence (TL) dating. In the TL dating of porcelain using the pre-dose technique, the β dose from the internal natural radiation in the body of porcelain is the first, the environmental dose the second, and the α dose negligible. Sample thickness of 0.2―0.5 mm was used in the paleodose calibration. For a porcelain sample of such thickness, the distribu- tion of β dose inside the sample was nonlinear when the sample (aluminium re- places porcelain in this experiment) was irradiated by a laboratory 90Sr-90Y β source. Therefore, the β dose used was only an average value. A distribution curve of β dose and the calculation of average β dose in the sample were obtained, according to the build-up and attenuation effects of β dose in the sample. The results showed that a sample thickness of 200 μm resulted in an average dose increment of about 4% compared to the surface whereas for a sample with a thickness of 400 μm, the average dose reduced by the same percentage, and that for a sample of 300 μm in thickness the average dose is equal to surface dose approximately. The average β dose in samples with various thickness can be obtained by the provided equations.

关键词： thermoluminescence dating porcelain paleodose build-up attenuation average beta dose

Valence Distribution in AT_xV_(6-X)O_(11) Compounds

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Journal of Materials Science & Technology 1999年第6期15卷 551-554页

作者： Hongchao LIU and Changlin KUO(shanghai Institute of Ceramics, Chinese Academy of Sciences, shanghai 200050, China) shanghai Institute of Ceramics Chinese Academy of Sciences Shanghai 200050 China

The distribution of trivalent and tetravalent cations in several ATxV6-xO11 compounds was quantitatively studied by the bond valence method. In SrV6O11, the M(3) sites were mainly occupied by trivaient cations; while M(1) and M(2) sites were shared by trivalent and tetravalent cations, the relative content of tetravalent at M(1) sites was higher than at M(2) sites. During substitution process, the trivalent cations preferred to occupy M(3) sites, tetravalent ones preferred to occupy M(2) sites. The occupancy of trivalent and tetravalent cations at M sites would change with the substitution

关键词： AT X)O Valence Distribution in AT_xV Compounds

X-ray Powder Diffraction Pattern of Bi_4(SiO_4)_3

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Journal of Materials Science & Technology 1997年第2期13卷 145-148页

作者： Hongchao LIU Changlin KUO (shanghai Institute of Ceramics, Chinese Academy of Sciences, shanghai 200050, China) shanghai Institute of Ceramics Chinese Academy of Sciences Shanghai 200050 China

In cooperation with figure-of-merits the Rietveld analysis can appraise both angular and intensity data of powder diffraction. In this work, X-ray diffraction pattern of Bi4(SiO4)3 was redetermined with intensity figure-of-merits, which qualify agreement between observed and calculated relative intensities. F30 is 158.90 (0.0059, 32), intensity figure of merit Rint is 8.7, I20(17), 8.0. The values of figure-of-merits show that the data of JCPDS cards are distorted. Both the experimental and calculated peak positions and heights are listed in detail.

关键词： SiO4 X-ray Powder Diffraction Pattern of Bi4 Bi

Formation and Oxidation Resistance of Silicide Coatings for Mo and Mo-Based Alloys

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Journal of Materials Science & Technology 2001年第4期17卷 479-481页

作者： Yu WANG , Yunpeng LI and Xingfang HU shanghai Institute of Ceramics, Chinese Academy of Sciences, shanghai 200050, China shanghai Inst. of Ceramics Chinese Acad. of Sci. Shanghai 200050 China

The forming process of silicide coatings on pure Mo and Mo-base alloys, obtained by the gas- phase deposition method. has been studied by examining the microstructure of coatings and the relationship between coating thickness and process parameters. It was shown that the growth of coatings was diffusion-controlled, the diffusion of silicon to be coated into Mo or Mo-base alloys was mainly responsible for the formation of silicide. The relationship between initial silicide thickness and oxidation resistance was also investigated, and the equation of service life of the coatings at high temperature in air is presented.

关键词： Mo Formation and Oxidation Resistance of Silicide Coatings for Mo and Mo-Based Alloys

COMPUTER　SIMULATION　OF　STRUCTURE　OF　MOLTEN　DyF_3－BaF_2－LiF　SYSTEM　BY　MONTE　CARLO　METHOD

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中国有色金属学会会刊：英文版 1996年第4期6卷 31-34页

作者： Xu Chi Su Hang Chen Nianyi(shanghai Institute of Metallurgy,Chinese Academy of Sciences,shanghai 200050) shanghai Institute of Metallurgy Chinese Academy of Sciences Shanghai 200050 China

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关键词： rare-earth fluoride molten salt computer simulation Monte Carlo method local structure

Densification and Microstructure of β-sialon/Nano-size SiC Composites

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Journal of Materials Science & Technology 1997年第4期13卷 339-341页

作者： Cheng ZHANG Danyu JIANG Qiang LI and Weiying SUN (shanghai Institute of Ceramics, Chinese Academy of Sciences, shanghai 200050, China) shanghai Institute of Ceramics Chinese Academy of Sciences Shanghai 200050 China

β-sialon/nano-size SiC composite ceramic with DyAG(Dy3Al5O12) as grain boundary phase was fabricated through hot-pressing. The effect of nano-size SiC on densification, phase composition, microstructure and mechanica... 详细信息

关键词： Nano SiC Densification and Microstructure of sialon/Nano-size SiC Composites

Tape Casting of Al_2O_3-TiB_2/Al_2O_3-Nano-TiC Multilayer Composites

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Journal of Materials Science & Technology 1997年第4期13卷 324-326页

作者： Yuping ZENG Dongliang JIANG Shouhong TAN and Jingkun GUO(shanghai Institute of Ceramics, Chinese Academy of Sciences, shanghai 200050, China) shanghai Institute of Ceramics Chinese Academy of Sciences Shanghai 200050 China

Ceramic tapes, containing Al2O3-25 wt pct TiB2(B) and Al2O3-25 wt pct nano-TiC (c), have been obtained by tape casting process. Numerous tapes (about 60～80 tapes) were prepared by stacking in turn the composition (B) and (C), laminating under 10 MPa pressure, eliminating the solvent and burning out the polymer additives. The final green bodies were hot pressed at 1750℃ and 30 MPa. The composite has a bending strength of 568 MPa and a fracture toughness of 5.8 M Pa·m1/2. SEM analysis exhibits that Al2O3 particle growth was inhibited by TiC particles in C. but TiB2 particles could not hinder Al2O3 growth in B. The curves of GTA indicates that all organic additives could be removed completely above 600℃

关键词： Nano TiB Al Tape Casting of Al2O3-TiB2/Al2O3-Nano-TiC Multilayer Composites TiC