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排序方式: 共有1411条查询结果,搜索用时 31 毫秒
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913.
In this study, we assessed the cross-cultural generalizability of the Reactive–Proactive Aggression Questionnaire (RPQ) and tested the hypotheses that boys show higher levels of proactive aggression with increasing age and that a two-factor (reactive–proactive) structure will be observed in an East Asian population. We administered the RPQ to 5,615 male and female 11- to 15-year-old schoolchildren. CFA demonstrated a good fit of the two-factor reactive–proactive model. Proactive aggression increased significantly with age in boys but not girls, whereas reactive aggression showed no gender difference and only a minimal age increase. Results suggest the presence of meaningful differences between these aggression subtypes and the generalizability of the RPQ in an East Asian population. 相似文献
914.
编制与多维自我控制理论相适应的,用于测量中国青少年多维自我控制的量表并检验其信、效度。通过查阅文献、专家评估等方式形成初测问卷; 以初中生和高中生为被试,选取1424名被试进行初测,681名被试正式施测。主动性自我控制量表包含情绪调节、目标维持和自我控制策略3个维度,抑制性自我控制量表包含注意力控制、冲动控制和情绪控制3个维度。两个量表均具有良好的结构效度、效标关联效度和信度。综上所述,青少年多维自我控制量表中的主动性、抑制性自我控制量表均符合测量学标准,可用于评估中国青少年的自我控制能力。 相似文献
915.
This article investigates how different sources of management support promote coworker helping behavior in organizations. We contend that senior management, managers responsible for Human Resource practices, and team leaders contribute to coworker assistance by encouraging employees to identify with the organization. Based on survey evidence drawn from nine Australian (N?=?1,349 employees) and six Chinese firms (N?=?828 employees), and using structural equation modeling, we show that organizational identification mediates the effects of perceived support from these three sources on coworker assistance. Differences in the strength of relationships between the variables are highlighted and discussed. 相似文献
916.
M. Yu. Gutkin A. L. Kolesnikova I. A. Ovid'Ko N. V. Skiba 《Philosophical Magazine Letters》2013,93(12):651-657
A theoretical model is presented which describes a new mechanism of plastic deformation in fine-grained materials. In the framework of the model, rotational deformation occurs via motion of dipoles of grain-boundary disclinations and is associated with the emission of lattice dislocations from grain boundaries into adjacent grain interiors. Ranges of defect system parameters are identified in which the disclination motion is energetically favourable. It is shown that the mechanism can contribute to plastic flow in fine-grained materials prepared by highly non-equilibrium methods such as ball milling, severe deformation and high-pressure compaction. 相似文献
917.
A formalism for optimized many body (OMB) potentials to describe the interatomic interactions in fcc metals is described. The OMB approach is based on the Tersoff potential, widely used to describe covalently bonded materials, and is closely related to the charge optimized many body (COMB) potential formalism for oxides. OMB extends to first nearest neighbors only, and employs a third-order Legendre polynomial to distinguish fcc and hcp structures, the strength of which can be adjusted to match the intrinsic stacking fault energy to arbitrary precision. The potential also predicts generalized stacking fault energy curves that are in very close agreement to the values determined from electronic-structure calculations. This potential is thus well-suited to investigating mechanical properties such as plastic deformation at the atomic scale. 相似文献
918.
Miao-Gen Chen Sen-Jiang Yu Zhi-Wei Jiao Ming-Zhou Yu Fu-Bing Bao 《Philosophical Magazine Letters》2013,93(3):122-127
In this article, we report an atomic force microscopy study on the microstructure and the deposition-rate dependence of granular size distribution in copper (Cu) ramified aggregates on a liquid substrate. This study shows that the ramified Cu aggregates are composed of Gaussian size distribution granules, which form immediately after the Cu atoms are deposited. The interesting phenomenon is that the mean diameter Φm of the granules exponentially decays and approaches a stable value Φc with an increase in the deposition rate f. The granular mean diameter Φm slightly changes with the time interval Δt during which the film is kept in the vacuum chamber, owing to the large diffusion coefficient of the Cu granules on the liquid substrates. The experimental behavior strongly depends on the properties of the liquid substrate. 相似文献
919.
O.Yu. Kontsevoi O. N. Mryasov Yu. N. Gornostyrev A. J. Freeman M. I. Katsnelson A. V. Trefilov 《Philosophical Magazine Letters》2013,93(5):427-433
The electronic structure of the 100 {010} edge dislocation in NiAl has been calculated using the real-space tight-binding linear muffin-tin orbital recursion method with a self-consistent treatment of electron density redistribution effects in the dislocation core. We demonstrate that quasilocalized states may exist in this metallic system as a result of specific lattice distortions in the dislocation core with 'broken bonds'. 相似文献
920.
The interaction between a glissile cluster of self-interstitial atoms and a vacancy has been studied in f -Fe by atomistic modelling and elasticity theory. It was found that vacancies can annihilate only with the cluster edge. Vacancies inside the cluster glide prism do not annihilate with interstitials but affect the cluster dynamic properties. Depending on the cluster size and ambient temperature, these vacancies reduce or even prevent cluster motion. Qualitative differences in the results of atomistic and elasticity theory approaches were found, thereby demonstrating the need for the atomistic approach. 相似文献