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Magnesiumandmagnesiumalloyshavebeenin vestigatedashydrogenstoragematerialsforseveralde cadesbecausefarmorehydrogenbyweightcanbestoredinthemthaninmostoftheothercurrentlyknownhydrogenstoragealloys .Moreover ,thehighnaturalabundanceofMg ,itslightmassandenviron mentalcompatibilitypotentiallymakemagnesiumoneofthemostprospectivecandidatesforfuturehydrogenstoragematerials .Unfortunately ,thepracticalappli cationofMganditsalloyshasbeenlimitedonlytocertainstoragedevicebecauseoftheirpoorhydriding dehydr… 相似文献
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本文研究了纤维体积分数对三维编织芳纶纤维增强铸性尼龙(简称K3D/MCPA)复合材料力学性能的影响。研究表明,K3D/MCPA复合材料有优异的抗冲击性能,冲击强度比三维编织芳纶纤维增强铸性尼龙(简称C3D/MCPA)和纯基体均有大幅度的提高,且随着纤维体积的提高而升高。K3D/MCPA复合材料剪切强度随纤维体积比的增大而增大,其纵向剪切强度低于纯基体和C3D/MCPA复合材料,但其横向剪切强度高于它们。K3D/MCPA复合材料弯曲强度与弯曲模量随纤维体积比的提高而提高,但与相同体积比的C3D/MCPA相比,K3D/MCPA的弯曲强度与弯曲模量均较低。 相似文献
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Two studies examine complementarity (vs. mimicry) of dominant and submissive nonverbal behaviors. In the first study, participants interacted with a confederate who displayed either dominance (through postural expansion) or submission (through postural constriction). On average, participants exposed to a dominant confederate decreased their postural stance, whereas participants exposed to a submissive confederate increased their stance. Further, participants with complementing responses (dominance in response to submission and submission in response to dominance) liked their partner more and were more comfortable than those who mimicked. In the second study, complementarity and mimicry were manipulated, and complementarity resulted in more liking and comfort than mimicry. The findings speak to the likelihood of hierarchical differentiation (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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Crystalline Behavior and Magnetic Properties of Nd60Fe30-x Al10Cox(x = 0,5,10) Bulk Amorphous Alloys
Crystalline behavior and magnetic properties of Nd60Fe30-xAl10Cox( x = 0, 5, 10) bulk amorphous alloys were investigated by differential scanning calorimeter (DSC), X-ray diffraction (XRD) and the vibrating sample magnetometer (VSM). Neither glass transition nor supercooled liquid region before crystallization was observed for the as-cast Nd60Fe30-xAl10Cox ( x = 0,5,10) bulk amorphous alloys. The glass forming ability can be improved significantly by the addition of Co. The as-cast Nd60Fe30-xAl10Cox (x = 0,5,10) alloys show hard magnetic behavior. With the addition of Co content, intrinsic coercivity (iHc) increases while the saturation magnetization(σs) and remanence (σr) decrease. The Curie temperature for the as-cast Nd60Fe30-xAl10Cox alloys increases from 451 K for x =0 to 468 K for x = 10. Some pre-cipitation of crystalline phases does not affect the hard magnetic properties of Nd60Fe30-xAl10Cox(x = 0,5,10) alloys, while the hard magnetic behavior disappears quickly after the alloys being completely crystallized. 相似文献
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Review of book: Media violence and its effects on aggression: Assessing the scientific evidence, by Jonathan L. Freedman. Toronto: ON: University of Toronto Press, 2002, 227 pp. Hardcover. ISBN 0-8020-3553-1. Reviewed by Claire Crooks. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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The ability to accurately and reliably predict whether an older adult will commit suicide has eluded clinicians and researchers. A random national sample of psychologists who work with older adults was surveyed regarding their perception of 36 risk factors for completed suicide and indirect self-destructive behavior in older adults. This study produced a profile of psychologists' assessment and treatment practices when working with suicidal older adults. Determining what psychologists consider to be the most salient risk factors for completed suicide is important in identifying a minimum standard that clinicians should follow when assessing older adults. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献