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161.
The effects of pressure on the mechanical and dynamical stability of NaAlSi have been fully investigated by first-principles calculations within the generalised gradient approximation (GGA). The obtained results show that the optimised lattice constants, atomic positions and elastic constants at ambient pressure are in good agreement with the available experimental and theoretical data. The lattice constants decrease monotonically with increasing pressure. The elastic constant C11, C12, C13, C33 and C66 increase while C44 decreases with increasing pressure. It is found that NaAlSi is mechanically unstable when the pressure is above 25.97?GPa. The phonon-dispersion curves along several high symmetry lines are obtained. The phonon frequencies at the Z point decrease with increasing pressure and completely soften to zero at 27.52?GPa, further confirming the structural instability of NaAlSi.  相似文献   
162.
从契约制定过程角度,探究个体制定契约参与度对人际信任的影响及其机制。现场研究结果表明参与制定宿舍契约能提升宿舍人际信任,认同感在其中起中介作用。实验室实验结果表明:契约参与度不但能提升被试对其他被试的情感(善心)和认知(依赖)信任,而且能提升被试在信任游戏中对其他被试的信任行为; 并且认同感在前者的关系中起中介作用。综合两个研究结果,契约参与度能提高对共同参与制定契约的同伴的信任,且社会认同能解释这种影响。  相似文献   
163.
为考察安全感和社会比较倾向在羞怯与攻击之间关系的中介作用,采用大学生羞怯量表、社会比较倾向量表、安全感量表和攻击问卷对543名大学生进行测量。结果发现(1)羞怯、攻击和社会比较倾向三者之间呈显著两两正相关,且三者分别与安全感呈显著负相关;(2)羞怯对攻击的直接效应显著;(3)安全感和社会比较倾向在羞怯与攻击关系间起完全中介作用。  相似文献   
164.
Double‐discount is an effective format for promoting purchase decisions. However, extant literature has overlooked how temporal order of discounts applied affects consumers’ purchase decisions. In this paper, we show that the sequence of discount magnitude (e.g., 10% followed by 40% vs. 40% followed by 10%) leads to biases in consumer judgment and influences the perceived appeal and purchase intention of the deal. We term this the double‐discount sequence effect. Using four experiments, we showed that double‐discount in an ascending sequence (e.g., taking 10% off, then an additional 40% off) is preferable over that in a descending sequence. We also found that discount application sequence—but not the presentation order—matters to consumers. Consumers anchor on the first discount they encounter and evaluate the second discount with respect to this first one.  相似文献   
165.
Associations between first-year maternal employment and mother—and youth-reported externalizing behavior at age 15 were examined paying attention to potential mediating roles of home and child care environments by 36?months, effortful control at 54?months, and externalizing behavior at 54?months and middle childhood. We used data from the NICHD Study of Early Child Care and Youth Development (n?=?922 non-Hispanic White children) which is a prospective birth cohort study that followed children from birth to age 15. Full-time first-year maternal employment was associated with higher levels of externalizing behavior at age 15 through higher maternal depressive symptoms by 36?months, lower effortful control at 54?months, and higher externalizing behavior at 54?months and middle childhood. Part-time first-year maternal employment was not associated with higher externalizing behavior at age 15.  相似文献   
166.
以参与网络课堂的387名大学生为被试,考察自我效能感、内隐智力信念和动机调节等学习者特征对网络学习环境中学习投入的影响及其作用机制。结果表明:(1)网络学习者的自我效能感、动机调节、内隐智力信念均能正向预测学习投入;(2)动机调节在自我效能感和学习投入的关系中起部分中介作用;(3)"自我效能感→动机调节→学习投入"这一中介效应的后半路径受到学习者内隐智力信念的调节。相较于智力实体论者,动机调节的中介效应在智力增长论者中更强。  相似文献   
167.
Attention, the mechanism by which a subset of sensory inputs is prioritized over others, operates at multiple processing stages. Specifically, attention enhances weak sensory signal at the perceptual stage, while it serves to select appropriate responses or consolidate sensory representations into short-term memory at the central stage. This study investigated the independence and interaction between perceptual and central attention. To do so, I used a dual-task paradigm, pairing a four-alternative choice task with a visual search task. The results showed that central attention for response selection was engaged in perceptual processing for visual search when the number of search items increased, thereby increasing the demand for serial allocation of focal attention. By contrast, central attention and perceptual attention remained independent as far as the demand for serial shifting of focal attention remained constant; decreasing stimulus contrast or increasing the set size of a parallel search did not evoke the involvement of central attention in visual search. These results suggest that the nature of concurrent visual search process plays a crucial role in the functional interaction between two different types of attention.  相似文献   
168.
The nexus between religion and mental health in the East has been understudied, where the coexistence of multiple religions calls for scholarly attention to religious identification. This article investigates the impact on self‐reported depression of an individual's identification with Christianity in a non‐Judeo‐Christian and religion‐regulating social setting. Taking advantage of the Chinese General Social Survey 2010, our empirical analyses suggest that people who explicitly identify with Christianity report a significantly higher level of depression compared with both religious nones and self‐claimed Buddhists. In contrast, there is no significant difference in self‐reported depression between religious nones and self‐identified Buddhists. This study supplements current literature on the connection between religious affiliation and mental health with a particular interest in East Asia, suggesting that the consequence on mental health of religious identification is contingent on a religion's social status, and a religion's marginal position may turn religious identification into a detrimental psychological burden.  相似文献   
169.
Xingming Hu 《Ratio》2017,30(3):255-269
Veritism claims that only true beliefs are of basic epistemic value. Michael DePaul argues that veritism is false because it entails the implausible view that all true beliefs are of equal epistemic value. In this paper, I discuss two recent replies to DePaul's argument: one offered by Nick Treanor and the other by Kristoffer Ahlstrom‐Vij and Stephen Grimm. I argue that neither of the two replies is successful. I propose a new response to DePaul's argument and defend my response against a possible objection. 1  相似文献   
170.
The aim of the present study is to reveal the most critical underlying factor influencing the mechanical properties of metal matrix composites (MMCs). It is shown that the mechanical properties of MMCs are essentially governed by the degree of strain localisation during plastic deformation. In other words, the MMCs exhibit superior mechanical performance only if the strain localisation is obviously inhibited and the accumulated stresses can be effectively transferred out. The work provides a new perspective in guiding the design of next-generation high-performance MMCs by suppressing the strain localisation as far as possible.  相似文献   
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