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991.
992.
Localised shear deformation of a material is usually identified as a particular feature of deformation inhomogeneity. Here, we show two different types of shear deformation-behaviour that occurred in Au–Cu multilayers subjected to microindentation load, namely, a cooperative-layer-buckling-induced shear banding in a nanoscale multilayer and a direct localised shearing across a layer interface along a shear plane in a submicron-scale multilayer. Theoretical analysis indicates that the formation of the two different types of shear deformation in the multilayers depends on a competition between the dislocation-pile-up-induced stress concentration at the layer interface and the barrier strength of the layer interface for glissile dislocation transmission. 相似文献
993.
Cyclic deformation has been performed at ambient temperature on ultrafine-grained copper processed by equal channel angular pressing. Observations by electron channelling contrast in a scanning electron microscope revealed that pronounced recrystallization occurred and several distinct dislocation configurations such as dislocation walls and labyrinth structures were found within the recrystallized regions. A model is proposed to account for the evolution of recrystallization, emphasizing that its development results from an interaction between the cyclic deformation and the growth of recrystallized regions. The formation of recrystallized regions of different sizes is discussed. 相似文献
994.
The light yield of Y3+-doped PbWO4 crystals increases after low-dose-rate irradiation with?γ?rays, and the radiation hardness is sensitive to annealing temperature. In the PWO growth procedure, an excess of PbO in the starting materials is a convenient method of compensating for PbO volatility. The relationship between the excess of PbO and the abnormal radiation behaviour has been investigated. The mechanism of the normal excess of PbO in the growth of PWO: Y3+ is discussed. 相似文献
995.
Nanometre-sized kinks and cracks formed in 6H SiC under ball milling (BM) at room temperature have been observed and characterized on the atomic scale using high-resolution electron microscopy (HREM). Observations of the kinks show that numerous positive and negative partials are aligned at either of the kink boundaries, and the stacking sequences in the kink band are considerably different from those in the other areas. It was also observed that the (0001) lattice planes in the kink band are kinked, indicating that microplasticity occurs in the normally brittle material SiC under BM even at room temperature. HREM observations of cracks show that cracks previously observed by transmision electron microscopy are not completely open but are at the initiation stage of fracture. Inside a crack, one residual kink region can be clearly observed, which indicates a correlation between kink and crack, that is a crack evolves from a kink. 相似文献
996.
This cross-sectional study applied self-determination theory to understand the relationship between coaching behaviors, psychological need satisfaction, and intrinsic motivation among young Chinese athletes from 2 universities in Macao, China (N = 208). In the path model with the demographics adjusted, coaching behaviors (training instruction, democratic behaviors, autocratic behaviors, social support, and positive feedback) and need satisfaction (perceived autonomy, competence, and relatedness) explained 44% of the variance in intrinsic motivation. We also found indirect effects of some coaching behaviors on intrinsic motivation through satisfying the psychological needs. Furthermore, independent self-construal significantly moderated the relationship between perceived relatedness and intrinsic motivation. 相似文献
997.
Mark H. C. Lai Maggie Y. W. Ren Anise M. S. Wu Eva P. W. Hung 《Journal of community & applied social psychology》2013,23(2):128-142
Although there is a large volume of research on the relationship between social identity and volunteerism, little attention was given to national identity in volunteerism research. This study examined the role of national identity in motivating people to volunteer in the Chinese culture and its role in differentiating those who showed no interest in voluntary work (i.e. non‐volunteers) from those who wanted to volunteer but did not (i.e. potential volunteers). Two hundred ninety‐nine participants (age, M = 34.14 years) filled out a questionnaire on their demographics, experience of volunteering, intention to volunteer, volunteer motivations, and national identity. Results showed that a stronger national identity was associated with greater volunteer motivations. Mediation analyses further supported the positive indirect effect of national identity on intention to volunteer through strengthening volunteer motivations. Marital status was the only significant factor that differentiated current volunteers from potential volunteers. We concluded that citizens’ volunteer motivation increases with national identity, yet concrete measures to bring potential volunteers to actual volunteering need to be further explored. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
998.
Nan Wu 《Journal of cognition and development》2013,14(2):302-313
Individual social differences have been addressed in recent studies, and the oxytocin receptor gene (OXTR) is the major candidate in explaining various social phenotypes. To study the association between a well-known haplotype (rs53576) of OXTR and children's prosocial behavior and its relationship with theory of mind (ToM) ability, 87 children (aged 3 to 5 years old) participated in 3 prosocial tasks and ToM performance experiments. Participants who were homozygous for the G allele (GG) exhibited more prosocial behaviors than did those with 1 or 2 copies of the A allele (AA), and GG carriers also displayed better ToM ability than did AA individuals. Further tests showed differences between genotypes in helping and comforting, albeit not in sharing. The results demonstrated that OXTR rs53576 was related to individual differences in ToM and was associated with prosocial behavior. 相似文献
999.
Yue Qi Fen Wu Xiaofeng Peng Ralph E. Steuer 《Journal of Multi-Criteria Decision Analysis》2013,20(3-4):127-139
In this paper, we study corporate social responsibility (CSR) in China through the prism of investments. We work with large stocks and assess their CSR performance from agency CSR data. We formulate Chinese CSR by a multiple objective extension of a traditional portfolio selection model and analytically solve the extension. We also solve the extension by a genetic algorithm and directly evaluate the algorithm's performance against the analytical solution. The multiple objective formulation is tested by randomly choosing nondominated portfolios with out‐of‐sample data to identify nondominated portfolios that outperform the 1/n portfolio (equally weighted portfolio). Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
1000.