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No authorship indicated 《Canadian Metallurgical Quarterly》2004,59(8):673
Provides the biography of Sheldon Cohen and announces that he has received the APA Award for Distinguished Scientific Contributions (2004) for his elegant research in psychoneuroimmunology. The award citation and a selected bibliography are also provided. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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J. Gegner 《Materialwissenschaft und Werkstofftechnik》2003,34(3):290-297
Chemical Composition and Microstructure of Polymer‐Derived Glasses and Ceramics in the Si–C–O System. Part 2: Characterization of microstructure formation by means of high‐resolution transmission electron microscopy and selected area diffraction Liquid or solid silicone resins represent the economically most interesting class of organic precursors for the pyrolytic production of glass and ceramics materials on silicon basis. As dense, dimensionally stable components can be cost‐effectively achieved by admixing reactive filler powders, chemical composition and microstructure development of the polymer‐derived residues must be exactly known during thermal decomposition. Thus, in the present work, glasses and ceramics produced by pyrolysis of the model precursor polymethylsiloxane at temperatures from 525 to 1550 °C are investigated. In part 1, by means of analytical electron microscopy, the bonding state of silicon was determined on a nanometre scale and the phase separation of the metastable Si–C–O matrix into SiO2, C and SiC was proved. The in‐situ crystallization could be considerably accelerated by adding fine‐grained powder of inert fillers, such as Al2O3 or SiC, which permits effective process control. In part 2, the microstructure is characterized by high‐resolution transmission electron microscopy and selected area diffraction. Turbostratic carbon and cubic β‐SiC precipitate as crystallization products. Theses phases are embedded in an amorphous matrix. Inert fillers reduce the crystallization temperature by several hundred °C. In this case, the polymer‐derived Si–C–O material acts as a binding agent between the powder particles. Reaction layer formation does not occur. On the investigated pyrolysis conditions, no crystallization of SiO2 was observed. 相似文献
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介绍了选针片式小提花横机常见选针故障的各种原因,并对不同原因导致的选针故障提出了针对性解决方法。 相似文献
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No authorship indicated 《Canadian Metallurgical Quarterly》2004,59(8):728
Provides the biography of Dante Cicchetti and announces that he has received the APA Award for Distinguished Senior Career Contributions to Psychology in the Public Interest (2004) for his seminal role in bridging theory, research, and practice by fostering the emergence and coalescence of the field of developmental psychopathology. A selected bibliography is also provided. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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No authorship indicated 《Canadian Metallurgical Quarterly》2004,59(8):787
Provides the biography of Cortney S. Warren and announces that she has received the APA Psi Chi/APA Edwin B. Newman Graduate Research Award (2004) for an outstanding research paper whose findings examine the potential for ethnicity to protect against body image disturbance by moderating the relationships between awareness and internalization of a thin physical ideal and body dissatisfaction. A selected bibliography is also provided. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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采用微波高压制样技术,快速提取饲料中的氟元素,结合氟离子选择性电极标准添加和电位极差测试方法,能够快速、准确地测试饲料中的含氟量 相似文献
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创建选区是Photoshop中最基本,也是最重要的技法之一。该文归纳了Photoshop中选区的多种方法和思路,阐明了各种方法的优势和特点,探讨如何综合运用各种工具和命令,充分发挥各工具特点,从而快速精确的建立选区。 相似文献
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具有多约束QoS动态组播路由选择问题,实质上是一个NP完全问题.在参见文献[1-2]的基础上,提出了一种改进的遗传算法.在初始化群体阶段采用改进的深度优先搜索机制,克服了局部搜索能力差的缺点,在交叉、变异阶段采用类似罚值函数的方法,加快了收敛速度,同时用C 编程语言实现了遗传算法在多约束QoS动态组播路由选择问题. 相似文献