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221.
Dafan Du Jiang Wang Yves Fautrelle Zhongming Ren Rene Moreau 《Philosophical Magazine Letters》2015,95(8):425-432
The application of a high magnetic field is capable of inducing the formation of aligned equiaxed grains in alloys during directional solidification. The alignment and refinement of the grains is enhanced as the magnetic field intensity increases. The thermoelectric power difference at the liquid/solid interface in four alloys has been measured in situ during directional solidification and it is concluded that the formation of aligned equiaxed grains in a magnetic field should be attributed to the combined action of a thermoelectric magnetic force and a magnetization force. 相似文献
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The directional solidification process of ternary Ag42.4Cu21.6Sb36 eutectic alloy within a wide growth rate range from 2 to 60 μm/s was accomplished at a constant temperature gradient of 50 K/cm. As growth rate increases, the ternary (θ(Cu2Sb) + ε(Ag3Sb) + Sb) eutectic morphology evolves from “lamellar (θ + ε) plus fibrous (Sb)” structure into “(θ + Sb) fibres in continuous ε matrix” structure. The θ and (Sb) phase spacings decrease with the increase of growth rate according to power functions with exponent values of 0.55 and 0.56, respectively. It is also found that the microhardness of directionally solidified Ag42.4Cu21.6Sb36 alloy samples is enhanced with the increase of growth rate, and the decrease of θ and (Sb) phase spacings. 相似文献
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This special issue of Memory brings together research from around the globe, from Japanese, Chinese and East Indian cultures, to American and European societies, to the Caribbean, to Turkey and to Australia and New Zealand, which examines how and why people, from childhood to old age, remember the personal past in daily life. This journey highlights the important role of the cultural context in shaping the functional usages of autobiographical memory. We illuminate six major contributions of cross-cultural research to a broader and deeper understanding of the functions of autobiographical memory, and call attention to the filed that memory research must “go global.” 相似文献
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This study investigated explicit knowledge of autobiographical memory functions using a newly developed questionnaire. European and Asian American adults (N = 57) and school-aged children (N = 68) indicated their agreement with 13 statements about why people think about and share memories pertaining to four broad functions—self, social, directive and emotion regulation. Children were interviewed for personal memories concurrently with the memory function knowledge assessment and again 3 months later. It was found that adults agreed to the self, social and directive purposes of memory to a greater extent than did children, whereas European American children agreed to the emotion regulation purposes of memory to a greater extent than did European American adults. Furthermore, European American children endorsed more self and emotion regulation functions than did Asian American children, whereas Asian American adults endorsed more directive functions than did European American adults. Children's endorsement of memory functions, particularly social functions, was associated with more detailed and personally meaningful memories. These findings are informative for the understanding of developmental and cultural influences on memory function knowledge and of the relation of such knowledge to autobiographical memory development. 相似文献
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Ameneh Shahaeian Julie D. Henry Maryam Razmjoee Ali Teymoori Cen Wang 《Developmental science》2015,18(5):671-685
Previous research has consistently indicated that theory of mind (ToM) is associated with executive control in the preschool years. However, interpretation of this literature is limited by the fact that most studies have focused exclusively on urbanized Western cultural samples. Consequently, it is not clear whether the association between ToM and executive control reflects the specific features of this particular cohort or instead reflects a universal pattern. The present study provides the first empirical assessment of these two constructs in three diverse groups of Iranian children. Participants were 142 preschoolers (4–5 years old) from high–socioeconomic status (SES) urban (n = 33), low–SES urban (n = 37) and rural villages (n = 77). The results show that there is a robust association between ToM and executive control in all three groups, and that executive control contributes significant unique variance to ToM understanding, even after controlling for a range of variables that have been proposed as potential confounders of this relationship. However, although the three groups were equated in ToM, significant differences in executive control were evident. Moreover, cluster analysis identified three distinct clusters that were relatively homogeneous with respect to executive control and SES. One of these clusters was characterized by both low SES and low executive functioning, and showed little evidence of ToM understanding. Taken together, these findings provide possibly the clearest evidence to date that the association between ToM and executive control is not dependent on children's previous experiences on the tasks, or their family and cultural background. A video abstract of this article can be viewed at https://www.youtube.com/watch?v=dxh_-3gCB8o 相似文献
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