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881.
    
Edge misfit dislocations (MDs) formed as result of reactions between 60° glissile threading dislocations and 60° MDs lying on an intersecting glide plane were found in strained GeSi-on-Si(001) and Ge-on-InGaAs/GaAs films. It was demonstrated that dislocations penetrating from the InGaAs buffer layer to the strained Ge film can provoke formation of not only 60° MDs, but also edge MDs on the interface even at minor mismatch of the lattice parameters of the film and the InGaAs/GaAs virtual substrate.  相似文献   
882.
    

In this letter we employ high-precision Monte Carlo simulations to investigate tracer diffusion kinetics for diffusion via divacancies in the bcc lattice. We utilize the mechanisms originally identified by Mehrer in which the divacancy can move by nearest-neighbour jumps with stable first-nearest-neighbour, second-nearest-neighbour and fourth-nearest-neighbour configurations of the divacancy. The tracer correlation factor and the 'impurity-form' correlation factor were found to be some 4-6% lower than those found by the matrix method. The tracer diffusion data and isotope effect for sodium were revisited in terms of monovacancy and divacancy contributions. The main change is a revision upwards from 0.55 to 0.61 of the j K kinetic factor for divacancies.  相似文献   
883.

The nature of impurity-dislocation interactions is one of the key questions governing the strength and plasticity of solid-solution materials. To investigate the influence of impurities on the mechanical properties of intermetallic NiAl, the electronic structure and energy of NiAl with a <100>{010} edge dislocation and transition-metal impurities was calculated using the real-space tight-binding linear muffin-tin orbital method. The localized electronic states, appearing in the core of the dislocation, are found to lead to strong impurity-dislocation interactions via two mechanisms: firstly, chemical locking, due to strong hybridization between impurity electronic states and dislocation localized states; secondly, electrostatic locking, due to long-range charge oscillations caused by the electron localization in the dislocation core. The results obtained explain qualitatively why the solid-solution hardening effect in NiAl correlates with the electronic structure of impurities rather than with size misfit, as expected according to traditional views.  相似文献   
884.
The influence of ferritic steel samples with different case-depths on the distortion behaviour of magnetic excitation voltage has been investigated. The systematic changes in the height and position of the peak and the trough on the ((dVE/dt) vs. VT) profile (distortion analysis of the magnetic excitation, DAME profile) reflect the difference in the magnetization process and hence the effect of distortion of VE in samples with different case-depths. This study shows the potential of this simple DAME method for evaluation of ferromagnetic steel components.  相似文献   
885.
    
Social cognition research investigates the way information present in the social environment is represented and used in adaptively guiding behavior. Representations of persons and of social relationships form the basic building blocks of social cognition, and we review what is known about how such representations are constructed and constituted. In particular, we review a range of mechanisms whereby observers can infer the psychological qualities of the actors they encounter, including relatively automatic processes as well as more thoughtful and deliberative ones. Prominent approaches for situating person representations within the context of interpersonal relationships are also reviewed. Copyright © 2010 John Wiley & Sons, Ltd. This article is categorized under:
  • Psychology > Reasoning and Decision Making
  相似文献   
886.
887.
    
This article presents information on the development and initial validation of the 16-item Response to Intervention (RTI) Beliefs Scale. The scale is designed to measure the extent to which educators working in schools hold beliefs consistent with the tenets of RTI. The authors administered the instrument to 2,430 educators in 62 elementary schools in the fall of 2007 and 2,443 educators in 68 elementary schools in the spring of 2008. Exploratory, single-level confirmatory, and multilevel confirmatory factor analysis procedures were used to examine construct validity. Results supported a correlated 3-factor model (Academic Abilities and Performance of Students with Disabilities, Data-Based Decision Making, and Functions of Core and Supplemental Instruction) at both the school and educator levels of analysis. Furthermore, the factor scores derived from the model demonstrated significant, positive relations to RTI implementation. Reliability estimates for two of the three factor scores exceeded.70. Implications for research on educator beliefs and implementation of RTI as well as implications for school psychologists supporting RTI implementation are discussed.  相似文献   
888.
889.
    
Laypersons' chains of reasoning in explaining recent influenza outbreaks are investigated. Drawing on social representations theory, fundamental worldviews, that is, the belief in a dangerous world (BDW), are postulated to anchor explanations of disease origins, which in turn affect perceived effectiveness of protection measures. Our study, based on a longitudinal survey among the general public in Switzerland, showed that the lower people's BDW scores, the more they appeal to natural origins to explain outbreaks and the more they perceive official protection measures as effective. The higher people's BDW scores, the more they explain outbreaks via hygienic origins, which are linked with out‐group discrimination measures, and conspiracy origins, which are linked with lower perceived effectiveness of aid intervention measures. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   
890.
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