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951.
An enhancement of the UV-visible optical absorption spectra of Ag nanoparticles (NPs) deposited on indium tin oxide (ITO) surfaces of different resistance by a seed-mediated growth technique is presented. A bicolour coherent beam, obtained from a pulsed Nd:YAG laser providing a 1060-nm fundamental wavelength and a double-frequency one at 530?nm, was used. A significant change in the optical density is observed for Ag NPs on low-resistance ITO surfaces (≈4?Ω/square), while almost nothing occurs with high-resistance (≈50?Ω/square surfaces). The spectral position of the maximal absorption at 440?nm is almost preserved in both cases. This result is explained in terms of a local photoinduced static field and surface-plasmon polaritons interacting with photoexcited phonons. A grating effect, arising from the coherent bicolour light forming a superstructure as for quantum crystals, could be another contribution. 相似文献
952.
It is known that the binary Cu–2?wt.% Be alloy can be strengthened by ageing its supersaturated solution at 523?K. The increase in the strength arising from ageing is because of the formation of GP zones. The same level of strength is achieved by ageing the supersaturated solid solution of a dilute binary Cu–4?wt.% Ti alloy at 723?K. In contrast to Cu–2?wt.% Be alloy, the increase in strength in this alloy occurs on account of spinodal decomposition of the as-quenched microstructure through the mechanism of clustering and ordering. In the present study, decomposition of a supersaturated solid solution of the ternary Cu–4?wt.% Ti–2?wt.% Be alloy was studied. Whereas ageing of this alloy at 523?K resulted in the formation of GP zones like in a Cu–2?wt.% Be alloy, ageing at 723?K resulted in a spinodally decomposed microstructure as in a Cu–4?wt.% Ti alloy. The decomposition of the ternary alloy at the two temperatures by two different mechanisms indicates that Be and Ti in solution in Cu act, more or less, independently of each other during ageing. 相似文献
953.
954.
Fergus I.M. Craik 《Memory (Hove, England)》2013,21(5-6):305-318
In this article I first briefly survey some enduring legacies of the Craik and Lockhart (1972) article on levels of processing (LOP) and address some common criticisms. In the next section I discuss whether memory can be regarded as “pure processing”, the role of short-term memory in an LOP framework, measurement of “depth” in LOP, encoding-retrieval interactions, the concept of consolidation, and the reality of “levels” of processing. In the final section I offer some speculations on future directions, discussing the notion of levels of representation and a possible continuing role for LOP in memory research. 相似文献
955.
Prospective memory (PM) refers to remembering to perform an action in the future. One hundred and twenty-nine students completed a laboratory event–based PM task as well as depression and anxiety questionnaires. The data were analysed with the beta-MPT version of the multinomial processing tree model of event-based PM. Thereby, the prospective and retrospective components of PM were estimated for each participant and were then correlated with depression and anxiety. State anxiety was negatively correlated with the prospective component of PM. Neither depression nor trait anxiety were related to either component of PM. 相似文献
956.
In this article we outline a “sub-process view” of working memory capacity (WMC). This view suggests that any relationship between WMC and another construct (e.g., reading comprehension) is actually a relationship with a specific part of the WMC construct. The parts, called sub-processes, are functionally distinct and can be measured by intrusion errors in WMC tasks. Since the sub-processes are functionally distinct, some sub-process may be related to a certain phenomenon, whereas another sub-process is related to other phenomena. In two experiments we show that a sub-process (measured by immediate/current-list intrusions) is related to the effects of speech on prose memory (semantic auditory distraction), whereas another sub-process (measured by delayed/prior-list intrusions), known for its contribution to reading comprehension, is not. In Experiment 2 we developed a new WMC task called “size-comparison span” and found that the relationship between WMC and semantic auditory distraction is actually a relationship with a sub-process measured by current-list intrusions in our new task. 相似文献
957.
Abstract Hintzman (1991; 1992) has claimed that the reason data points approximate the recognition failure function discovered by Tulving and Wiseman (1975) is that they are mathematically constrained to do so, and the reason that a few data points do not approximate the function, but are exceptions to it, is that these data points are less subject to mathematical constraints. He has additionally argued that such exceptions are more likely with low levels of recall and strong underlying sources of positive covariance. We provide empirical evidence relevant to this mathematical model using 301 observations from a database of all relevant experimental conditions published between 1973 and 1992 (Nilsson & Gardiner, 1993). We conclude that mathematical constraints have only a minor influence on the function, not the causal role assigned to them in Hintzman's (1992) model. By our account, both the function and exceptions to it reflect a single psychological principle, the functional effectiveness of contextual cues. 相似文献
958.
In creativity, there is scant evidence of significant racial and gender differences, and when such differences are found, there is no consistency regarding which groups perform best. There has been little work focusing on racial and gender biases and/or stereotypes within creativity assessment. It is study these issues by using a modified version of the Consensual Assessment Technique in which the judges are provided with information about the creators' gender and/or race. A total of 455 undergraduates assigned ratings for creativity, writing ability, and enjoyment to 60 poems downloaded from a poetry Web site. These poems either had no attribution or had (fictional) stereotypical Black, White, and Crossover names for each gender. Results suggest that novice raters using CAT methodology display little evidence of bias in their ratings of creativity, writing ability, and poem enjoyment. Very slight preference was found for poems assigned names of White females. 相似文献
959.
The present article reports a controlled intervention study concerning the effects of a nondirected use of pictures of works of art as a way of stimulating creativity in elderly institutionalized women. Participants were randomly allocated either to the intervention (n = 20) or to the control (n = 20) group. After the intervention significant improvement in ratings between the groups was measured, with the intervention group more open and flexible and with a stronger deposition to a creative behavior than subjects in the control group. They also showed greater freedom and variation than the control group in drawing circles and making pictures. In puzzle tests the intervention group constructed increasingly imaginative, irregular, and open alternatives with colored patterns. The control group constructed closed and black forms. Importantly, the status of increased creativity continued to exist four months after the intervention. No changes were seen in the control group. This group showed a rational and precautious personality. 相似文献
960.
Morris I. Stein 《创造力研究杂志》2013,25(3):294-300
What role does emotion play in helping youth reach their creative potential? Does it alter how they process ideas, and how many ideas they can generate? By varying the levels of arousal associated with low, medium, and high levels of exertion in the video game Dance Dance Revolution, and inducing a positive or negative mood, this study offers evidence that emotion significantly affects creativity through the interaction of arousal and valence. Faced with the cognitive demand of creativity, lower arousal levels resulted in higher creativity scores when coupled with a negative mood. At high arousal levels, a positive mood resulted in greater creative potential than a negative mood. These results are discussed here in light of theories of emotion as a prime, as information, and as a moderator of attention. 相似文献