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51.
B. Lucas A. El Amrani M. Chakaroun B. Ratier R. Antony A. Moliton 《Thin solid films》2009,517(23):6280-11905
We have fabricated pentacene-based transistors on a transparent and flexible substrate made of polyethylene-terephthalate. We have shown that using an optical excitation at a wavelength of 365 nm photoconductivity modifies the carrier density without changing the mobility. The performance of the flexible organic phototransistors is mostly due to high-photosensitivity in the off-state with a ratio of photocurrent to dark current of about 2 104. Furthermore, the response times of the phototransistor are lower than 0.1 s. These results indicate that such transistors could be potentially used in photodetectors or amplifiers ordered by an optical gate. Moreover, we have noticed that there is no significant change in the mobility value when the transistor is bent in the direction of the current flow. 相似文献
52.
Browne A 《Neural computation》2002,14(7):1739-1754
To give an adequate explanation of cognition and perform certain practical tasks, connectionist systems must be able to extrapolate. This work explores the relationship between input representation and extrapolation, using simulations of multilayer perceptrons trained to model the identity function. It has been discovered that representation has a marked effect on extrapolation. 相似文献
53.
Rheology of methane hydrate slurries during their crystallization in a water in dodecane emulsion under flowing 总被引:1,自引:0,他引:1
Annie Fidel-Dufour 《Chemical engineering science》2006,61(2):505-515
An original experimental set-up was developed and used for studying crystallization and rheology of methane hydrate/water/dodecane system. Methane is injected in a water in dodecane emulsion at low temperature and high pressure in order to form methane hydrate crystals and to move the suspension by gas lift. It behaves as a Newtonian fluid. Dynamic viscosity and conversion of water and gas into gas hydrate crystals were measured during the process for various water contents. Experimental results were explained by means of a model including nucleation, growth and agglomeration. Due to the high value of crystal and drop concentrations, agglomeration takes place through three-body collisions between one water drop and two already formed agglomerates. Resulting agglomerates were considered as fractal-like ones. During crystallization and agglomeration, the effective volume fraction of drops and porous agglomerates is increased, and then suspension viscosity increases. When all water drops are crystallized, agglomeration stops and viscosity does not change. 相似文献
54.
Robert H. Dodds Antony R. Ingraffea Karl-Heinz Schwalbe 《Engineering Fracture Mechanics》2006,73(15):2091-2092
55.
56.
Jetten Jolanda; Spears Russell; Manstead Antony S. R. 《Canadian Metallurgical Quarterly》1998,74(6):1481
We tested the prediction, derived from an integration of social identity and self-categorization principles, that the relation between in-group distinctiveness and positive differentiation is curvilinear. Moderate distinctiveness is argued to provide the critical combination of intergroup difference (self-categorization theory) and intergroup similarity ( social identity theory ) to elicit intergroup differentiation. Intergroup distance (differences in group central tendencies) and group variability were manipulated orthogonally, resulting in different levels of intergroup distinctiveness (low, intermediate, and high). In line with predictions, in-group bias and positive differentiation were greatest, for both minimal and natural groups, when the combination of group variability and intergroup distance produced intermediate levels of group distinctiveness. The potential of this integrative model to account for disparate findings is discussed. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
57.
Antony D. Radford 《Computer aided design》1981,13(6):345-350
Designing windows in buildings is a multicriteria, multivariable design problem with many constraints. This paper examines the different natures of the window design information that can be provided through mathematical simulation and optimization models and considers some approaches to choosing a solution. 相似文献
58.
Soo EC Aubry AJ Logan SM Guerry P Kelly JF Young NM Thibault P 《Analytical chemistry》2004,76(3):619-626
A novel method employing CE-ESMS and precursor ion scanning was developed for the selective detection of nucleotide-activated sugars. By using precursor ion scanning for fragment ions specific to the different nucleotide carriers, i.e., ions at m/z 322 for cytidine monophosphate, m/z 323, 385, and 403 for uridine diphosphate, m/z 362, 424, and 442, for guanosine diphosphate, and m/z 346, 408, and 426 for adenosine diphosphate, it was possible to selectively detect sugar nucleotides involved in the biosynthesis of glycoconjugates such as glycoproteins and lipopolysaccharides. Enhancement of sensitivity was achieved using N-(2-hydroxyethyl)piperazine-N'-(2-ethanesulfonic acid) as a sample stacking buffer and provided detection limits between 0.2 and 3.8 pmol.mL(-)(1). The present CE-ESMS method provided linear dynamic ranges over the concentrations 0.2-164 nM (r(2) = 0.952-0.997) for different nucleotide sugar standards. The application of this method is demonstrated for the identification of intracellular pools of sugar nucleotides in wild type and isogenic mutants from the bacterial pathogen Campylobacter jejuni. By using product ion scanning (with and without front-end collision-induced dissociation), it was possible to determine the precise nature of unexpected sugar nucleotides involved in the biosynthesis of pseudaminic acid, a sialic acid-like sugar previously observed on the flagellin of some pathogenic bacteria. 相似文献
59.
Krumhuber Eva; Manstead Antony S. R.; Cosker Darren; Marshall Dave; Rosin Paul L.; Kappas Arvid 《Canadian Metallurgical Quarterly》2007,7(4):730
Detecting cooperative partners in situations that have financial stakes is crucial to successful social exchange. The authors tested whether humans are sensitive to subtle facial dynamics of counterparts when deciding whether to trust and cooperate. Participants played a 2-person trust game before which the facial dynamics of the other player were manipulated using brief ( 相似文献
60.
We have investigated the dephasing processes in a weak localization (WL) experiment of a two-dimensional electron system on
liquid helium. From low-field magnetoconductivity measurements we can separate the damping of WL on the dephasing of electrons
due to electron–electron interaction and the motion of the helium vapour atoms. We observe an intermediate regime where both
damping mechanisms are of comparable importance and determine the cross-over from one dominant regime to the other. 相似文献