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Much research has explored how spoken word recognition is influenced by the architecture and dynamics of the mental lexicon (e.g., Luce and Pisoni, 1998; McClelland and Elman, 1986). A more recent question is whether the processes underlying word recognition are unique to the auditory domain, or whether visually perceived (lipread) speech may also be sensitive to the structure of the mental lexicon (Auer, 2002; Mattys, Bernstein, and Auer, 2002). The current research was designed to test the hypothesis that both aurally and visually perceived spoken words are isolated in the mental lexicon as a function of their modality-specific perceptual similarity to other words. Lexical competition (the extent to which perceptually similar words influence recognition of a stimulus word) was quantified using metrics that are well-established in the literature, as well as a statistical method for calculating perceptual confusability based on the phi-square statistic. Both auditory and visual spoken word recognition were influenced by modality-specific lexical competition as well as stimulus word frequency. These findings extend the scope of activation-competition models of spoken word recognition and reinforce the hypothesis (Auer, 2002; Mattys et al., 2002) that perceptual and cognitive properties underlying spoken word recognition are not specific to the auditory domain. In addition, the results support the use of the phi-square statistic as a better predictor of lexical competition than metrics currently used in models of spoken word recognition.  相似文献   
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We have searched for the production by virtual photons of short-lived particles that exhibit muonic decay. We used Brookhaven's 10.5 GeV/c muon beam and examined the two and three-muon final states. The sample of 158 trimuon events is due almost entirely to QED tridents. The sample of 673 dimuons can be accounted for in part by asymmetric tridents and in part by the decay of π and K mesons. We obtain an upper limit for the production of other short-lived particles of the order of < 150 pb/nucleon, where B is the branching ratio for muonic decay. From the trident sample we establish that muons obey Fermi-Dirac statistics at the level of 8 standard deviations.  相似文献   
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Zusammenfassung Acetylaceton und Benzoylaceton bilden mit elektronegativ substituierten Phenylhydrazinen, selbst mit 2,4-Dinitrophenylhydrazin, und selbst wenn die Reaktion bei Zimmertemperatur durchgeführt wird, 1,3,5-tri-substituierte Pyrazole ohne nachweisbare Mengen von Zwischenprodukten (Monophenylhydrazone).5-Methoxypentan-2,4-dion bildet mit p-Nitrophenylhydrazin bei Zimmertemperatur ein Monophenylhydrazon. Bei höherer Temperatur wird aber auch hier das entsprechende Pyrazol gebildet.
Summary Acetylacetone and benzoylacetone react with electro-negatively substituted phenylhydrazines to form 1,3,5-trisubstituted pyrazoles, also with 2,4-dinitrophenylhydrazine and even if the reaction is performed at room temperature. There are no detectable quantities of intermediate products (monophenylhydrazones).5-Methoxypentane-2,4-dione is forming with p-nitrophenylhydrazine at room temperature a monophenylhydrazone, but at higher temperature the corresponding pyrazole is also formed.


Wir möchten nicht unterlassen, dem Carlsbergfond unseren Dank für eine finanzielle Unterstützung auszusprechen.  相似文献   
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Platinum‐based catalytic materials have received significant attention, particularly in the shape and size control of faceted materials for catalysis. More recently, there has been a rapid increase in the number of reports of successful preparations in this field; however, a fundamental understanding of controlled growth towards catalytic material design is essential for future implementation and broad application. In this review, we provide an overview of the recent findings reported since 2009, focusing on methods for shape control as well as the effects of exposed surface facets on select catalytic reactions. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   
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