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901.
The surface tensions of liquid ternary Ni–5%Cu–5%Fe, quaternary Ni–5%Cu–5%Fe–5%Sn and quinary Ni–5%Cu–5%Fe–5%Sn–5%Ge alloys were determined as a function of temperature by the electromagnetic levitation oscillating drop method. The maximum undercoolings obtained in the experiments are 272 (0.15T L), 349 (0.21T L) and 363?K (0.22T L), respectively. For all the three alloys, the surface tension decreases linearly with the rise of temperature. The surface tension values are 1.799, 1.546 and 1.357?N/m at their liquidus temperatures of 1719, 1644 and 1641?K. Their temperature coefficients are ?4.972?×?10–4, ?5.057?×?10?4 and ?5.385?×?10?4?N/m/K. It is revealed that Sn and Ge are much more efficient than Cu and Fe in reducing the surface tension of Ni-based alloys. The addition of Sn can significantly enlarge the maximum undercooling at the same experimental condition. The viscosity of the three undercooled liquid alloys was also derived from the surface tension data.  相似文献   
902.
A study was carried out on the deformation of nanocrystalline cobalt. For cold-rolled nanocrystalline cobalt, the X-ray diffraction peaks narrowed instead of broadened on deformation. The results of transmission electron microscopy showed that grain size (17.8?nm on average) was not increased. The results can be explained in terms of the production and activity of vacancies and vacancy clusters.  相似文献   
903.
The structures of the binary ZrCr2 and ZrCr2 Laves phase with addition of V have been investigated by high-resolution transmission electron microscopy (HRTEM). The results show that annealed ZrCr2 is the cubic C15 phase with micro-twins. In contrast, annealed Zr(CrV)2 has a lamellar microstructure with a character of long-period stacking sequences. Further studies by HRTEM indicate that annealed Zr(CrV)2 is the di-hexagonal C36 with a coalescence of 5-, 6- and 8-layer long-period stacking structures. The effect of V addition on the structural stability of ZrCr2 is discussed.  相似文献   
904.
Prior research on mood management through media consumption has encountered mixed results. This study seeks to address these discrepancies by incorporating time of measurement into the examination of regulatory outcomes and by identifying trait-like cognitive moderators that presumably are involved in the regulation of negative moods. Results showed that sad mood initially fostered longer listening to mood-compatible music but such preference decreased over time, suggesting the merits of considering temporal changes in the mood-repair process. In addition, ruminative trait was found to be a significant factor in how people cope with their sad moods, whereas mood salience was not.  相似文献   
905.
The present research examined the association between belief about immutability of moral character and punitiveness toward criminal offenders. Overall, participants who believed that moral character is immutable (entity theorists) were more punitive than those who believed that it is changeable (incremental theorists). More important, the present research identified two mediational paths: Entity theorists made more internal attribution of criminal behavior and held stronger expectation of offenders' recidivism, both of which in turn led to stronger punitiveness. Also, contrary to some researchers' speculation, entity theorists did not perceive less controllability in criminal behavior. Implications for implicit theory research and criminal justice research are discussed.  相似文献   
906.
The increasing global popularity of men’s lifestyle magazines offers a unique opportunity to study how advertising constructs masculinity across cultures. This study conducted a content analysis of 636 ads from the three most popular men’s lifestyle magazines in Taiwan, China, and the United States to examine the representations of masculinity in their advertisements between 2008 and 2010. The objectives were to determine how masculinities are currently portrayed in terms of types and roles. The study found that the magazines from all three countries typically portrayed men as refined and sophisticated. The defining characteristic of global hegemonic masculinity is commodity consumption, with a particular emphasis on a trendy and refined appearance. We found no significant cross-cultural differences in the types of masculinity, namely, “Vigorous and Macho”, “Refined and Sophisticated”, and “Trendy and Cool”. The traditional preference for “Refined and Sophisticated” in Chinese and Taiwanese ads and a preference for “Vigorous and Macho” in the U.S. ads have largely disappeared. Instead, the global consumption market and its associated consumer culture are the primary determinants regarding representations of masculinity in men’s lifestyle magazine ads. This global culture may underlie the lack of differences found.  相似文献   
907.
Work flow policies are shown to induce a change in average between-workers variability (worker heterogeneity) and within-worker variability in performance times. In a laboratory experiment, the authors measured the levels of worker heterogeneity and within-worker variability under an individual performance condition, a work sharing condition, and a fixed assignment condition. The work sharing policy increased the levels of worker heterogeneity and worker variability, whereas the fixed assignment policy decreased them. These effects, along with work flow policy main effects on mean performance times and variability are examined. This article represents an initial step in understanding effects that may be important in the selection of an operating policy, the ignorance of which may lead to costly misestimates of performance.  相似文献   
908.
Attentional biases for negative interpersonal stimuli in clinical depression   总被引:14,自引:0,他引:14  
An information-processing paradigm was used to examine attentional biases in clinically depressed participants, participants with generalized anxiety disorder (GAD), and nonpsychiatric control participants for faces expressing sadness, anger, and happiness. Faces were presented for 1000 ms, at which point depressed participants had directed their attention selectively to depression-relevant (i.e., sad) faces. This attentional bias was specific to the emotion of sadness; the depressed participants did not exhibit attentional biases to the angry or happy faces. This bias was also specific to depression; at 1000 ms, participants with GAD were not attending selectively to sad, happy, or anxiety-relevant (i.e., angry) faces. Implications of these findings for both the cognitive and the interpersonal functioning of depressed individuals are discussed and directions for future research are advanced.  相似文献   
909.
This study examined the prospective relations among family history density of alcoholism (FHD), adolescent family harmony, and young adults' alcohol and drug dependence. Family harmony was rated by mothers and fathers in adolescence, and young adults' substance dependence diagnoses were obtained through structured interviews. Higher FHD predicted lower adolescent family harmony, which in turn increased young adults' odds of being diagnosed with drug dependence (with and without alcohol dependence) compared to no diagnoses or to alcohol dependence only. Family harmony also interacted with FHD such that the protective effect of family harmony on young adults' drug dependence with or without alcohol dependence decreased as FHD rose, and was nonsignificant at high levels of FHD. The findings suggest the importance of distinguishing among alcohol and drug dependence disorders and examining their differential etiological pathways, and also suggest that the protective effects of harmonious family environments on substance dependence may be limited at high levels of FHD.  相似文献   
910.
本文从冯友兰先生对"两行"的理解谈起,对"两行"的出处、思想根源和修养方法进行了分析,并据此将道家与禅宗的最高境界进行对照,得出了冯友兰先生的理解是错误的结论.  相似文献   
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