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排序方式: 共有1340条查询结果,搜索用时 15 毫秒
941.
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Eric J. Bosze Justin Carver Sheila Singson Joanna McKittrick Gustavo A. Hirata 《Journal of the American Ceramic Society》2007,90(8):2484-2488
White-light emission was achieved by activating yttrium oxyorthosilicate with two rare-earth elements, (Y1− m − n Ce m Tb n )2 SiO5 . Ce3+ strongly absorbs at λ ex =358 nm and produces a broad, mainly blue emission with a tail that extends out to 600 nm (orange), and transfers energy efficiently to Tb3+ , which produces strong green-line emissions at 550 nm and some red emission around 650 nm. At λe x =358 nm, chromaticity coordinates of the optimally activated (Y0.9625 Ce0.0075 Tb0.03 )2 SiO5 were found to be x =0.266, y =0.365 with a color temperature 8512 K. Upon mixing in another red-emitting phosphor, (Y0.955 Bi0.005 Eu0.04 )2 O3 , the chromaticity and color rendering index values were improved. 相似文献
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Pronin Emily; Kruger Justin; Savtisky Kenneth; Ross Lee 《Canadian Metallurgical Quarterly》2001,81(4):639
People, it is hypothesized, show an asymmetry in assessing their own interpersonal and intrapersonal knowledge relative to that of their peers. Six studies suggested that people perceive their knowledge of their peers to surpass their peers' knowledge of them. Several of the studies explored sources of this perceived asymmetry, especially the conviction that while observable behaviors (e.g., interpersonal revelations or idiosyncratic word completions) are more revealing of others than self, private thoughts and feelings are more revealing of self than others. Study 2 also found that college roommates believe they know themselves better than their peers know themselves. Study 6 showed that group members display a similar bias—they believe their groups know and understand relevant out-groups better than vice versa. The relevance of such illusions of asymmetric insight for interpersonal interaction and our understanding of "naive realism" is discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
945.
Modeling and characterization of fiber-reinforced plastic honeycomb sandwich panels for highway bridge applications 总被引:5,自引:0,他引:5
Julio F. Davalos Pizhong Qiao X. Frank Xu Justin Robinson Karl E. Barth 《Composite Structures》2001,52(3-4):441-452
Fiber-reinforced plastic (FRP) composite decks have been increasingly used in highway bridge applications, both in new construction and rehabilitation and replacement of existing bridge decks. Recent applications have demonstrated that FRP honeycomb panels can be effectively and economically used for highway bridge deck systems. This paper is concerned with design modeling and experimental characterization of a FRP honeycomb panel with sinusoidal core geometry in the plane and extending vertically between face laminates. The analyses of the honeycomb structure and components include: (1) constituent materials and ply properties, (2) face laminates and core wall engineering properties, (3) equivalent core material properties, and (4) apparent stiffness properties for the honeycomb panel and its equivalent orthotropic material properties. A homogenization process is used to obtain the equivalent core material properties for the honeycomb geometry with sinusoidal waves. To verify the accuracy of the analytical solution, several honeycomb sandwich beams with sinusoidal core waves either in the longitudinal or transverse directions are tested in bending. Also, a deck panel is tested under both symmetric and asymmetric patch loading. Finite element (FE) models of the test samples using layered shell elements are further used to correlate results with analytical predictions and experimental values. A brief summary is given of the present and future use of the FRP honeycomb panel for bridge decks. The present simplified analysis procedure can be used in design applications and optimization of efficient honeycomb structures. 相似文献
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Ohne Zusammenfassung 相似文献
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Examines a situation that embodies the entire spectrum of perceived control ranging from extreme helplessness to extreme domination. The authors consider sexual trauma from the perspective of the victim. From the actor's perspective, an important distinction is made between choice and prediction. This shows that, even in situations of apparent helplessness, perceived control may be legitimate from the actor's perspective. From this perspective, current theoretical frameworks on control may have distorted the actor's reality. It is suggested that future research on perceived control should be guided by the actor's perspective. (French abstract) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献