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131.
Magnesium oxide (MgO) films and particles have been collected by pressurised filtration of a Mg-8.6wt%Al-0.67wt%Zn (AZ91D) alloy melt. The morphology of the oxides and their interfaces with the α-Mg phase were investigated by high-resolution transmission electron microscopy. It was found that the oxide films consisted of large numbers of sub-micrometre-sized MgO particles, and that melt shearing can effectively break up the oxide films and disperse the oxide particles. For the first time, orientation relationships (ORs) of OR I: [1?1?1]MgO~2° from (0?0?0?1)α-Mg and (0?1?1)MgO?//[2?1?1?0)α-Mg; and OR II: (1?1?1)MgO//(1?1?0?1)α-Mg and [0?1?1]MgO//[1?2?1?1]α-Mg, were observed between the MgO particles and the α-Mg matrix. The calculated Bramfitt planar disregistries were 5.5% and 2.5% for the two ORs, respectively, indicating good lattice matching between MgO and α-Mg at the interface. With the evidence of grain refinement effect observed in the sheared AZ91D magnesium alloy, the possibility of MgO particles to act as potent nucleants for heterogeneous nucleation of α-Mg grains is discussed in terms of the crystallographic criterion. 相似文献
132.
This study examined the impact of changes in level of current grief over time on changes in memory for past grief. Following from previous work on the impact of current affective state on memory for past affectively salient events, bereaved individuals who underwent a greater reduction in grief over time were expected to show a similar pattern of changes in memory for past grief. A sample of conjugally bereaved participants completed measures of current grief and memory for past grief at the time of the loss of their spouse at each of the 2, 6, 13, and 30 month post-loss time periods. As predicted, those who reported greater reduction in grief over the course of the study were more likely to remember their past grief as progressively less severe relative to those who underwent less reduction in grief over time. A nonrecursive causal model analysis verified that changes in memory for past grief were explained by changes in current grief. These results were discussed in terms of contemporary reconstructive memory accounts of the effect of affective state on memory. 相似文献
133.
Mark A. Barnett Mark A. Thompson Jane Schroff 《The Journal of genetic psychology》2013,174(4):489-498
Second-grade, fourth-grade, sixth-grade, high school, and college students (N = 140) were asked to describe situations in which they would not help someone else and their reasons for not helping in those situations. Younger subjects used perceived self-incompetence as a reason for not helping more frequently than did older subjects. In contrast, older subjects more frequently cited a desire not to violate another's personal situation and/or their own internalized values, laws, and rules as reasons not to help than did their younger counterparts. For a majority of the not-helping categories, however, no significant effect of age level was found, and indeed, some individuals in even the youngest age group expressed subtle and insightful reasons for not helping. 相似文献
134.
Errol Hamarat Dennis Thompson Don Steele Ken Matheny Carol Simons 《The Journal of genetic psychology》2013,174(3):360-367
The authors examined age differences in perceived coping resources and satisfaction with life across 3 older-adult age groups (45-64, 65-74, and 75 years and older). The 98 participants represented healthy, socially active, community-residing adults. Group comparisons were made on 12 individual coping scales, and an overall coping resource effectiveness score was computed. No significant differences were found for 11 of the coping resources or for overall coping resource effectiveness. Similar consistencies in life satisfaction were found across the 3 age groups. The findings indicate that (a) for healthy adults, the oldest old cope at least as effectively as their younger counterparts, despite their likelihood of encountering increased levels of stress; and (b) psychologically, old age may be viewed as a time of resilience and fortitude. 相似文献
135.
The Role of Perspective Taking and Empathy in Children's Machiavellianism,Prosocial Behavior,and Motive for Helping 总被引:1,自引:0,他引:1
Fourth- and fifth-grade children (N = 117) were categorized into high- and low-empathy and affective-perspective-taking (APT) groups based on their scores on the Bryant (1982) empathy scale and a modified version of the Rothenberg (1970) and Silvern, Waterman, Sobesky, and Ryan (1979) APT measures. Children in the low-empathy/high-APT group had significantly higher Machiavellianism scores on Braginsky's (1970) measure than did children in the other empathy/APT groups. Highly empathic children were rated by their teachers as more helpful under certain circumstances and cited other-oriented reasons for their own helping behavior more frequently than did less empathic children. 相似文献
136.
Striving toward goals is associated with higher levels of subjective well‐being; however, many potential roadblocks to goal achievement exist. The current study extends the understanding of goal regulation processes in its examination of the relationships between dispositional and situational goal adjustment to a profound stressor and their associations with psychological adjustment. Women (N = 103; M age = 57.2 years; 82% Caucasian) with metastatic breast cancer completed semistructured interviews and self‐report measures at study entry and 3 months later. Measures of dispositional and situational goal reengagement were significantly correlated, but dispositional and situational goal disengagement were unrelated. Greater dispositional and situational goal disengagement abilities were associated with fewer cancer‐related intrusive thoughts at Time 1. Dispositional and situational reengagement were positively associated with life satisfaction and sense of purpose and negatively associated with depressive symptoms at Time 1. However, greater initial situational goal disengagement predicted an increase in depressive symptoms over time. Both how an individual typically responds to goal blockage, as well as how an individual is currently responding to a specific blocked goal, appear related to psychological adjustment. 相似文献
137.
In the present study, we investigated how well Lee's (1973/1976) typology of love characterized response data that adult subjects provided on selected items written by Hendrick and Hendrick. Results suggest that the model represents response data reasonably well and that Hendrick and Hendrick's (1986) measure ought to be valid. 相似文献
138.
We examined whether facial expressions of performers influence the emotional connotations of sung materials, and whether attention is implicated in audio-visual integration of affective cues. In Experiment 1, participants judged the emotional valence of audio-visual presentations of sung intervals. Performances were edited such that auditory and visual information conveyed congruent or incongruent affective connotations. In the single-task condition, participants judged the emotional connotation of sung intervals. In the dual-task condition, participants judged the emotional connotation of intervals while performing a secondary task. Judgements were influenced by melodic cues and facial expressions and the effects were undiminished by the secondary task. Experiment 2 involved identical conditions but participants were instructed to base judgements on auditory information alone. Again, facial expressions influenced judgements and the effect was undiminished by the secondary task. The results suggest that visual aspects of music performance are automatically and preattentively registered and integrated with auditory cues. 相似文献
139.
140.
Grain-boundary migration is demonstrated to proceed by lateral propagation of a small step in a (113), [110] symmetric Al tilt grain-boundary. In-situ high-resolution (transmission) electron microscopy (HREM) at 523K allowed the study of atomic-scale detail at video rates during the migration process. The grain-boundary translational states on both sides of the step are identical, which leads to a step dislocation. This defect can move laterally by a combination of climb and glide. Dynamic HREM images indicate considerable atomic agitation within the dislocation core. A detailed temporal analysis of the step movements shows small random displacements of the dislocation core. 相似文献