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Background
Recently several studies have shown that people use contextual information to make predictions about the rest of the sentence or story as the text unfolds. Using event related potentials (ERPs) we tested whether these on-line predictions are based on a message-level representation of the discourse or on simple automatic activation by individual words. Subjects heard short stories that were highly constraining for one specific noun, or stories that were not specifically predictive but contained the same prime words as the predictive stories. To test whether listeners make specific predictions critical nouns were preceded by an adjective that was inflected according to, or in contrast with, the gender of the expected noun. 相似文献65.
Microwave heating of ceramic composites 总被引:1,自引:0,他引:1
The microwave heating of a ceramic composite is modelled andanalysed. The composite consists of many small ceramic particlesembedded in a ceramic cement. The composite is assumed to bewell insulated, and each particle is assumed to be in imperfectthermal contact with the surrounding cement. Based on thesetwo assumptions an asymptotic theory exploiting the small Biotnumber and small non-dimensional contact conductance is developed.Our asymptotic theory yields a set of nonlinear partial differentialequations which govern the temperature in the composite. Theseare reduced to a set of coupled nonlinear ordinary differentialequations in which the surface area of each particle entersas a parameter. Recent experiments with such composites haveshown that the steady-state temperature of the composite isstrongly dependent upon the radii of the embedded particles.Our model captures this effect. In fact, our analysis showsthat the assumption of imperfect thermal contact between theparticles and the ceramic cement is essential for this trendto be established. 相似文献
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Harding JR King CD Perrie JA Sinnott D Stachulski AV 《Organic & biomolecular chemistry》2005,3(8):1501-1507
We report a study of the glucuronidation of a number of important steroidal secondary alcohols. The alcohols studied are androsterone 7, epiandrosterone 8, 17-acetoxy-androstane-3alpha,17beta-diol 9, 11alpha-hydroxyprogesterone 10, and 3-benzoylestradiol 11. These were first glucuronidated using the Schmidt trichloroacetimidate method with variations in acyl substituent (viz. derivatives 2 and 3), Lewis acid catalyst and order of addition. The results are contrasted with those obtained using our recently described glycosyl iodide donor 4, catalysed either by N-iodosuccinimide (NIS) or various metal salts. 相似文献
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A two-photon laser-induced fluorescence study on the transport of ground-state atomic hydrogen in a supersonic plasma jet, generated from an Ar-H (2) mixture, reveals an unexpected shock pattern. Whereas both the axial-velocity profile and the temperature profile of hydrogen atoms along the jet centerline can be interpreted in terms of a supersonic expansion of an Ar-H gas mixture, the H-atom density profiles do not satisfy the well established Rankine-Hugoniot relation leading to a nonconservation of the forward flux. The experimental results show that H atoms escape from the supersonic expansion by a diffusion process due to strong density gradients between the core of the jet and its vicinity. 相似文献
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A. Baum S. Abdalah A. Geltrude M. Locatelli W. Perrie A. Taranu 《Optics Communications》2011,284(12):2771-2774
We report on the fabrication of optical Bragg type phase gratings in polymethyl methacrylate substrates by a femptosecond Ti: Sapphire laser. As for their optical characterization, a spatially resolved microscopy interferometric technique is used to investigate the two-dimensional distribution of the refractive index change produced by the irradiation process. The technique gives a direct and quantitative two-dimensional profile of the index of refraction in irradiated PMMA, providing information on how the fabrication process depends on the laser irradiation. 相似文献