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261.
This article proposes a factor, the critical electronegativity difference Δx cri, to correlate alloy composition with thermal stability and glass-forming ability of Al–Ni–RE (RE: Rare Earth element) ternary metallic glasses. The Al-rich metallic glasses with Δx > Δx cri exhibit glassy behavior, whereas alloys with Δx < Δx cri are nanocrystalline. Nanoglassy alloys occur when Δx ≈ Δx cri. The best glass formers are located near Δx cri. Furthermore, an equation has been deduced to calculate Δx cri with varying RE covalent atomic radius.  相似文献   
262.
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   
263.

Transmission electron microscopy has been used to reveal the microstructure of metastable C40 MoSi 2 thin films produced by annealing amorphous magnetron-sputtered deposits at 700°C. The films contain nanoscale acicular grains elongated parallel to (0001), with extensive basal faulting. The faults are intrinsic with R ´ 1/3[0001] and correspond to thin slabs of the equilibrium C11 b phase. It is proposed that these faults may act as nuclei for the subsequent transformation from C40 to C11 b by a process akin to discontinuous coarsening.  相似文献   
264.
After receiving knowledge regarding some topic, people usually overestimate their prior topic knowledge. Two experiments investigated whether people would claim less prior knowledge if they worked to earn their present knowledge. In Study 1, students finishing a psychology course claimed less precourse psychology knowledge if they reported devoting more effort toward the course. In Study 2, the knew-it-all-along effect was stronger for participants who were simply given the answers to questions than for participants who studied for 20 minutes to learn the answers. Both cognitive and motivational factors can account for the observed effects of effort investment on retrospective knowledge judgments.  相似文献   
265.
Lee (1999) argued that there would be two possible confounding variables in the word length effect. This study attempted to control those two variables. A possible confounding variable in the word-length effect is the neighborhood size. A shortword usually has more neighbors than a long word.Another confounding variable is different perceptual availability between inside and outside letters in a long word. Inside letters are easier to perceive than outside letters. Controlling of these two confounding variables in the two experiments eliminated the wordlength effect.  相似文献   
266.
A considerable amount of research in hope is driven by Snyder's (1994) model which proposes that hope is positively associated with agency thinking and pathways thinking. However, the current research suggests that hope as understood by the layperson (Hope) is only associated with agency thinking and not with pathways thinking. This was found over four studies using different agency and pathways variables, different Hope variables, different methods, and different cultures. Implications of these findings for Snyder's model are discussed.  相似文献   
267.
Inhibition of return (IOR) refers to the delay in responses to previously cued locations. Whether IOR influences perceptual and/or motor processes has been controversial. To determine IOR effects on perception and action, this study examined IOR in spatially directed hand reaching (Experiment 1) and spatial localization of targets with a mouse cursor (i.e., an indirect visuomotor mapping/perceptual task; Experiment 2). The reaction times showed delayed responses for targets appearing within the whole cued hemifield for both tasks. However, hypometric spatial biases were consistently found only with directed reaching. Spatial biases in the mouse localization task were indirectly influenced by IOR and distinct from those in the reaching task. The dissociation in spatial characteristics for directed reaching vs. perception suggests that the effects of IOR are task dependent, but may be more directly linked to the dorsal motor system.  相似文献   
268.
This study has established a relationship model encompassing such aspects as consumer values, consumer involvement, purchase behavior, and consumer satisfaction. Furthermore, taking counterfeit goods as an example, this study employs factor analysis, reliability analysis, and the structural equation model to verify the relationship between the research aspects. Another major discovery of this study was that teenagers' behavioral purchasing mentality is graphic, hyperlinked, and is geared toward useful situations and functional needs. When they consider their degree of need, they inevitably incorporate many emotional needs. However, their attitude toward counterfeit goods is rational, which is confirmed by the fact that Hypothesis 1 was not supported.  相似文献   
269.
This study explored the relationships between psychological contract types and innovative behavior. We focused on the mediating effect of work engagement and the moderating effect of job resources (organizational and social resources). Participants were 267 dyads of research and development engineers and their supervisors from 30 high‐tech companies. Moderated path analysis was used to test the hypotheses. Findings showed that: (a) work engagement fully mediated the negative relationship between transactional contracts and innovative behavior; in addition, it also fully mediated the positive relationship between relational contracts and innovative behavior; and (b) job resources attenuated the former and strengthened the latter mediating effects. These findings contribute to understanding how, why, and when psychological contract types lead to innovative behavior via work engagement.  相似文献   
270.
研究加工通道的差异以及减法和乘法心算的编码特征,选择100道心算算式,在视觉和听觉两种输入通道下记录并分析了14例正常人的脑事件相关电位(ERP)。结果发现,视觉和听觉通道引发了趋势相反的早中期成分,在额区和中央区产生了显著分离。在慢波阶段,听觉通道下更多激活了颞区,而视觉通道下更多激活了顶-枕区,且慢电位的ERP特征也表现出通道差异。减法和乘法运算以左半球激活为主,但听觉通道下的顶区和颞区出现了显著的右半球优势。减法在视觉通道下优势较大,说明其主要依赖视空间表征;而乘法在听觉通道下更具优势,则主要是由于其以听觉的言语表征方式为主。  相似文献   
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