材料期刊网

Process of Photoluminescence and Photostimulated Luminescence in BaFBr:Eu Phosphors

Wei CHEN (Lab. of Semiconductor Mater. Sci. , Institute of Semiconductor , Chinese Academy of Sciences , Beijing , 100083 , China)(To whom correspondence should be addressed)Mianzeng SU(Dept. of Chemistry , Peking University , Beijing , 100871 , China)

材料科学技术（英文）

The photoluminescence (PL) and photostimulated luminescence (PSL) of BaFBr:Eu phosphors are reported. In the photoluminescence of BaFBr:Eu, the emission of Eu2+ , e-h recombination and Eu3+ have been observed, while in the photostimulated luminescence only the emission of Eu2+ was observed. This phenomenon may be explained well by the suggestion of a two-band model for the host emission in which the host emission energy may transfer to Eu2+. The difference of excitation in those two processes results in different transfer rates which makes the PL and PSL emission different.

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Ion sputter erosion in metallic glass-A response to "Comment on: Homogeneity of Zr(64.13)Cu(15.75)Ni(10.12)Al(10) bulk metallic glass" by L-Y. Chen, Y-W. Zeng, Q-P. Cao, B-J. Park, Y-M. Chen, K. Hono, U. Vainio, Z-L. Zhang, U. Kaiser, X-D. Wang, and J-Z Jiang J. Mater. Res. 24, 3116 (2009)

Journal of Materials Research

The morphology of the dark and bright regions observed by transmission electron microscopy for the Zr(64.13)Cu(15.75)Ni(10.12)Al(10) bulk metallic glass strongly depends on the ion beam parameters used for ion milling. This indicates that the ion beam could introduce surface fluctuation to metallic glasses during ion milling.

关键词: room-temperature

CLAS+FROST: new generation of photoproduction experiments at Jefferson Lab.

中国物理C

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The effect of fiber inclusions in toughened plastics - Part II: determination of micromechanical parameters

Composites Science and Technology

Short glass fiber-reinforced nylon 6,6 with and without rubbery inclusions were injection molded into standard specimens. The mechanical properties and the residual fiber length distribution were measured. The macro-to-micro model proposed by Bowyer and Bader [J. Mater. Sci., 7 (1972) 1315] was used to determine the interfacial shear strength (IFSS). The IFSS in the toughened nylon 6,6-based composites was found to be superior to that in the untoughened nylon 6,6-based composites. This indicates that the presence of rubbery phase in the composite system contributed to the interfacial bonding between nylon 6,6 and glass fibers (GF). Back-scattered electron imaging taken on a plane perpendicular to the mold filling direction for fiber-reinforced toughened nylon 6,6 showed that the rubbery phase adhered to the GF surface. This morphological feature was regarded as a main factor responsible for the improvement of IFSS in the reinforced toughened nylon 6,6 composites. (C) 2004 Published by Elsevier Ltd.

关键词: glass fiber;nylon 6,6;reinforced polymers;glass;strength;behavior;microstructures;thermoplastics

Fatigue crack initiation and fracture behavior of a copper bicrystal with a perpendicular grain boundary

Materials Science and Engineering a-Structural Materials Properties Microstructure and Processing

By cyclically deforming a [(5) over bar 913]perpendicular to[(5) over bar 79] copper bicrystal with a perpendicular grain boundary (GB), the fatigue crack initiation and fracture behavior were investigated. It was found that only the primary slip systems were activated on both G1[(5) over bar 913] and G2[(5) over bar 79] grains including the vicinity of the GB at axial plastic strain range of 1.8 x 10(-4)-2.56 x 10(-3). By observing the surface and fractography, it was confirmed that the fatigue cracks always nucleated and propagated along the GB, and displayed an obvious tendency on different surfaces. On the front surface of the bicrystal, the intergranular cracking was more preferential than that on the lateral surface, even though the geometrical conditions among PSB, GB and stress axis on the lateral surface claimed to enhance cracking are more close to those proposed by Christ (Mater. Sci. Eng. A117 (1989) L25). Based on the experimental results above, the effect of the interaction of PSB with GB and stress axis on intergranular fatigue cracking in the bicrystal is discussed. It is suggested that Christ's geometrical conditions for intergranular cracking might be further developed and the plastic strain incompatibility near the GB should play a more important effect on intergranular fatigue cracking. (C) 1999 Elsevier Science S.A. All rights reserved.

关键词: copper bicrystal;cyclic deformation;grain boundary;fractography;intergranular cracking;nucleation

热烈祝贺ActaMetallurgicaSinica（EnglishLetters）被SCI收录

中国腐蚀与防护学报

由中国金属学会主办、中国科学院金属研究所承办的英文期刊ActaMetallurgicaSinica（EnglishLettersl于近日通过ThomsonReuters的评审，入选SCI数据库。该刊自2009年起出版的论文被ThomsonReuters旗下的ScienceCitationIndexExpanded（alsoknownasSeiSeareh），JournalCitationReports／ScienceEdition和CurrentContents@／EngineeringComputingandTechnol-ogy所收录。这是继（《金属学报》和《材料科学技术（英文版）》之后，金属所承办的又一被SCI收录的期刊。

关键词: SCI , 中国科学院金属研究所 , 中国金属学会 , 英文期刊 , 材料科学技术 , 数据库

热烈祝贺ActaMetallurgicaSinica（EnglishLetters）被SCI收录

中国腐蚀与防护学报

由中国金属学会主办、中国科学院金属研究所承办的英文期刊ActaMetallurgicaSinica（EnglishLettersl于近日通过ThomsonReuters的评审，入选SCI数据库。该刊自2009年起出版的论文被ThomsonReuters旗下的ScienceCitationIndexExpanded（alsoknownasSeiSeareh），JournalCitationReports／ScienceEdition和CurrentContents@／EngineeringComputingandTechnol-ogy所收录。这是继（《金属学报》和《材料科学技术（英文版）》之后，金属所承办的又一被SCI收录的期刊。

关键词: SCI , 中国科学院金属研究所 , 中国金属学会 , 英文期刊 , 材料科学技术 , 数据库

LaB6功能陶瓷材料的研究现状

郑树起 , 闵光辉 , 于化顺 , 韩建德 , 王维倜 , 张树玉

材料导报

综述了目前国内外LaB6功能陶瓷材料的研究概况及应用,综合了制备LaB6粉末、多晶、单晶的各种工艺.

关键词: LaB6 , 功能陶瓷 , 制备工艺

Chen系统的状态变量周期性反馈控制

李开明 , 李亚洲 , 冯维贵 , 林长

量子电子学报 doi:10.3969/j.issn.1007-5461.2007.05.014

采用非线性反馈控制,用附加了带参数的正弦项对Chen系统进行了有效的控制.随着参数k的逐渐增大,系统的动力学行为呈现出一系列的变化.数值研究结果表明:随控制参数的增大,驱动信号的强度渐大,混沌系统由混沌运动到周期轨道,最终到一相点.

关键词: 混沌 , Chen系统 , 不动点 , Lyapunov指数 , 反馈控制

A convenient phase transfer route for Ag nanoparticles

Physica E-Low-Dimensional Systems & Nanostructures

Generally, phase transfer of metal nanoparticles between aqueous phase and organic phase need two reagents at last. One is stabilizer of nanoparticles, the other is phase-transfer agent (Chem. Lett. 21 (1992) 1527; J. Colloid Interface Sci. 161 (1993) 471; J. Phys. Chem B 101 (1997) 9876; Chem. Commun. (1997) 537; Langmuir 14 (1998) 602; J. Phys. Chem B 103 (1999) 7238; Chem. Mater. 13 (2001) 4692; Langmuir 17 (2001) 733; Langmuir 16 (2000) 9775; Langmuir 18 (2002) 3364; J. Am. Chem. Soc. 123 (12001) 11148). In this paper, Ag nanoparticle prepared by tannic acid reduction of AgNO3 in aqueous medium were transferred to chloroform solution via a remarkably simple one-step route under the effect of phase-transfer inducer dimethyldioctadecylammonium chloride (DDAC), where no special stabilizer was required. Monolayer of Ag nanoparticles is obtained on carbon film by self-assembly using chloroform organosol. The effect of the inducer DDAC concentration is checked, and it was found that 5 x 10(-3) mol dm(-3) of DDAC was the optimum concentration for phase transfer of Ag nanoparticles. The organosol, Ag nanoparticle self-assembled monolayer and phase transfer were characterized by UV-vis spectra, TEM, ED and TF-IR. (C) 2004 Elsevier B.V. All rights reserved.

关键词: silver;nanostructures;UV-Vis spectroscopy;DDAC;organosol;modified gold nanoparticles;shape-controlled synthesis;silver;nanoparticles;colloidal gold;aspect-ratio;nanorods;toluene;nanodisks;platinum;water