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261.
In this article, we propose an efficient atomic packing cluster-based composition protocol to help design Al-based metallic glasses. Its validity is verified by some typical experimental data from the literatures. Furthermore, with this understanding, the Al–Ni–Y alloy system is re-evaluated. As a result, the best glass former Al86Ni9Y5 in this system, with the critical thickness of about 500 µm, is successfully fabricated by wedge casting. 相似文献
262.
Solubility criterion for sequential disordering in metal-metal multilayers upon solid-state reaction
An n-body Ni-Ti potential is derived and applied in a molecular dynamics simulation to study the maximum supersaturated solubility of the terminal solid solutions and solid-state reaction in a Ni/Ti bilayer. It reveals that during interfacial reaction of the Ni/Ti bilayer the Ti lattice reaches its maximum solubility by dissolving Ni earlier than Ni does through dissolution of Ti, which results in a sequential disordering of first Ti and then Ni, although Ti has a higher melting point than Ni. In the Ni-Zr, Ni-Mo and Ni-Ta systems, however, the Ni lattice collapses more rapidly because it reaches a maximum solubility earlier than its partners, which have higher melting points than Ni. A solubility criterion is thus relevant for all the above cases; the lower the maximum solid solubility the less stable is the lattice of the metal upon solid-state reaction. 相似文献
263.
J.J. Wang S. Bhattacharyya Q. Li T.W. Heo X.Q. Ma Long-Qing Chen 《Philosophical Magazine Letters》2013,93(7):327-335
An efficient numerical algorithm is proposed to accurately compute the elastic fields in two-dimensional (2D) or three-dimensional (3D) microstructures with arbitrary elastic inhomogeneity and anisotropy. It combines the equivalent inclusion method of Eshelby, the microelasticity theory of Khachaturyan, and the spectral iterative perturbation method of Hu and Chen. Its efficiency is compared with those of existing approaches in the literature. The method can be conveniently implemented in phase-field modeling of stress-dependent microstructure evolution and/or of mass/electrical transport. 相似文献
264.
265.
ResumenEn este trabajo, que conjuga la tradición psicométrica con la perspectiva de procesamiento de información, se estudió si las diferencias en rendimiento observadas en los tests están asociados a diferencias individuales en gasto atencional. Fueron seleccionados 4 grupos extremos de sujetos en función de dos factores de inteligencia (verbal y espacial), los cuales realizaron una tarea de verificación de frases (tarea primaria) aisladamente o en conjunción con una de emparejamiento perceptivo (tarea secundaria). Se utilizaron como variables dependientes el número de aciertos de la tarea primaria, en ambas condiciones, y en la tarea secundaria, con tiempo limitado; y el número de errores en ambas tareas, sin límite de tiempo. Los sujetos altos verbales tuvieron más aciertos que los bajos verbales al ejecutar la tarea primaria en solitario, e iguales diferencias se encontraron entre altos y bajos espaciales; no se observaron diferencias en el número de errores. Al realizar ambas tareas concurrentemente, los altos verbales tienen mayor número de aciertos y cometen menos errores, en la tarea primaria, que los bajos verbales; los altos y bajos espaciales se diferencian únicamente en el número de aciertos. Estos resultados son discutidos y comparados con estudios diferenciales recientes. 相似文献
266.
ABSTRACTSelf-referential processing has been proven to be effective in improving source memory. However, it is unclear whether different types of source information would be consistently enhanced when an item is self-referentially processed. In two experiments, the authors examined the influence of the self (compared with other-referencing and semantic processing) as well as learning intention (incidental/intentional learning) on memory for two types of source information (spatial location and colour) that differ in the amount of cognitive resources they require to be encoded in memory. Results show that self-referencing has enhanced memory for spatial location of words whatever this information is learned intentionally or incidentally, whereas it cannot facilitate memory for the colour of words under the intentional learning condition, nor can it under the incidental condition. These findings suggest that self-referential processing is beneficial in memory improvement but not all-powerful, a source self-reference effect is subject to source information type. 相似文献
267.
Roberto Colom Pei Chun Shih Carmen Flores-Mendoza Ma Ángeles Quiroga 《Memory (Hove, England)》2013,21(7):804-813
Storage-oriented memory span tasks with no explicit concurrent processing are usually referred as short-term memory (STM) tasks, whereas tasks involving storage plus concurrent processing requirements are designated as working memory (WM) tasks. The present study explores a question that remains unsolved: Do STM and WM tasks clearly tap distinguishable theoretical constructs? For that purpose, a large sample of 403 participants was tested through 12 diverse memory span tasks. Half of those tasks are widely accepted as measures of STM, whereas the other half measure WM. The results show that STM and WM share largely overlapping underlying capacity limitations, suggesting that all memory span tasks tap essentially the same construct. Some implications are discussed. 相似文献
268.
Are risk-takers more likely to engage in unethical behaviors? We examined the relationship between risk-taking propensity and cheating in two experimental studies. In Study 1, we examined the relationship between subjects’ risk-taking propensity and their actual self-serving dishonesty using a gambling-like task. The results suggested that risk-taking propensity, measured using a behavioral approach, was positively correlated with actual self-serving dishonest behavior. In Study 2, we measured participants’ performances using a matrices test and found that the positive correlation still held. We found that participants with high risk-taking propensity reported a lower perceived probability of being detected, which might drive their dishonest behavior. 相似文献
269.
ABSTRACTBackground and Objectives: Little is known how coping self-efficacy (CSE) interacts with coping in dyad everyday life. The present study examined the moderating role of daily CSE in the relationship between coping and the next-day positive (PA) or negative (NA) affect in patient-caregiver dyads, following hematopoietic stem cell transplantation.Design: This intensive longitudinal study was conducted during the first 28 days after post-transplant discharge.Methods: Patients and their caregivers (N?=?200) maintained daily diaries on CSE, coping strategies, and affect.Results: Daily CSE moderated daily coping–affect relationship: Positive emotion-focused coping increased PA in patients with higher than usual emotion-related CSE, whereas a buffering effect was found at lower than usual emotion-related CSE. A positive association between negative emotion-focused coping and NA in both patients and caregivers was stronger among those with lower than usual levels of emotion-related CSE. Higher than usual instrumental coping reduced NA in patients whose caregivers had higher than usual problem-related CSE, but increased NA for those whose caregivers had lower than usual instrumental CSE.Conclusion: The findings show that daily CSE contributes to the effectiveness of daily coping within dyad, confirming its significance in effective adaptation and the role in the dyadic coping process. 相似文献
270.
Heining Cham Stephen G. West Yue Ma Leona S. Aiken 《Multivariate behavioral research》2013,48(6):840-876
A Monte Carlo simulation was conducted to investigate the robustness of 4 latent variable interaction modeling approaches (Constrained Product Indicator [CPI], Generalized Appended Product Indicator [GAPI], Unconstrained Product Indicator [UPI], and Latent Moderated Structural Equations [LMS]) under high degrees of nonnormality of the observed exogenous variables. Results showed that the CPI and LMS approaches yielded biased estimates of the interaction effect when the exogenous variables were highly nonnormal. When the violation of nonnormality was not severe (normal; symmetric with excess kurtosis < 1), the LMS approach yielded the most efficient estimates of the latent interaction effect with the highest statistical power. In highly nonnormal conditions, the GAPI and UPI approaches with maximum likelihood (ML) estimation yielded unbiased latent interaction effect estimates, with acceptable actual Type I error rates for both the Wald and likelihood ratio tests of interaction effect at N ≥ 500. An empirical example illustrated the use of the 4 approaches in testing a latent variable interaction between academic self-efficacy and positive family role models in the prediction of academic performance. 相似文献