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81.
82.
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83.
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
84.
Sigrist M Fuhrer A Ihn T Ensslin K Ulloa SE Wegscheider W Bichler M 《Physical review letters》2004,93(6):066802
The Aharonov-Bohm effect is measured in a four-terminal open ring geometry. Two quantum dots are embedded in the structure, one in each of the two interfering paths. The number of electrons in the two dots can be controlled independently. The transmission phase is measured as electrons are added to or taken away from the individual quantum dots. Although the measured phase shifts are in qualitative agreement with theoretical predictions, the phase evolution exhibits unexpected dependence on the magnetic field. Phase lapses are found only in certain ranges of the magnetic field. 相似文献
85.
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
86.
P. Salgado‐Figueroa P. Jara‐Ulloa A. Alvarez‐Lueje J. A. Squella 《Electroanalysis》2013,25(6):1433-1438
In this work, a new method to quantify nitrofurantoin in aqueous media using a flow injection system connected to commercially available screen‐printed carbon nanofibers was developed. A pretreatment of the screen‐printed carbon nanofibers electrode with Britton? Robinson buffer/N,N‐dimethylformamide was applied to enhance the nitrofurantoin peak current signal in one step. The developed method was demonstrated to be sensible, reproducible, easy, and inexpensive. With a low detection limit, it is applicable to real samples. The results indicate that it is highly applicable for the detection of nitrofurantoin in several matrices. When urine samples without any pretreatment were analyzed, the method proved reproducible and sensible and had a low detection limit. The use of screen‐printed electrodes has advantages over other modified electrodes as a glassy carbon due to its versatility. 相似文献
87.
Novel liquid crystal materials based on 3,4-di-n-alkoxybenzoylthiosemicarbazides (3a–h, n = 5–10, 12, 14) were synthesised. The mesomorphic properties of these compounds were characterised and studied by differential scanning calorimetry, polarising optical microscopy and X-ray diffraction. Compound 3a did not show mesomorphic properties; 3b shows a monotropic hexagonal columnar (Colh) phase. Compounds 3c–h display an enantiotropic Colh phase. The mesomorphic properties were found to be dependent on the length of alkoxy side chains. In N,N-dimethylformamide solution, all the compounds displayed a room temperature emission with λmax at 361–332 nm. A thermogravimetric analysis also was performed. 相似文献