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91.
Beardsley Patrick M.; Aceto Mario D.; Cook Charles D.; Bowman Edward R.; Newman Jennifer L.; Harris Louis S. 《Canadian Metallurgical Quarterly》2004,12(3):163
Despite oxycodone's (4,5-epoxy-14-hydroxy-3-methoxy-17-methylmorphinan-6-one) history of clinical use and the attention it has received as a drug of abuse, few reports have documented its pharmacology's relevance to its abuse or its mechanism of action. The purposes of the present study were to further characterize the analgesic effects of oxycodone, its mechanism of action, and its effects in terms of its relevance to its abuse liability. The results indicate that oxycodone had potent antinociceptive effects in the mouse paraphenylquinone writhing, hot-plate, and tail-flick assays, in which it appeared to be acting as a μ-opioid receptor agonist. It generalized to the heroin discriminative stimulus and served as a positive reinforcer in rats and completely suppressed withdrawal signs in morphinedependent rhesus monkeys. These results suggest that the analgesic and abuse liability effects of oxycodone are likely mediated through μ-opioid receptors and provide the first laboratory report of its discriminative stimulus, reinforcing, and morphine cross-dependency effects. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
93.
Louis Kruh 《Cryptologia》2013,37(2):78-82
The third Britisher who, in addition to Alastair Denniston and Dillwyn Knox, met the Poles near Pyry in 1939 to to receive a copy of the Enigma machine has been wrongly identified as Stewart Menzies, head of the British foreign Intelligence service. In fact he was Humphrey Sandwith, head of the Admiralty's interception and direction-finding service. 相似文献
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The equations that govern the various transport phenomena occurring in a polymer electrolyte membrane fuel cell (PEMFC) were formulated and implemented in a commercial finite element software, in order to predict the fuel cell current density with respect to the operating conditions. The numerical model showed polarization curves in accordance with literature. The catalyst utilization was then improved by optimizing the platinum distribution (design variable) in the fuel cell, so as to maximize current density (objective function) for a fixed total amount of platinum (constraint). The first analysis showed that, for equal anode and cathode catalyst layer thicknesses, maximal current density was achieved by placing more catalyst in the cathode than in the anode. The second analysis showed that, for equal anode and cathode catalyst layer density, maximal current density was achieved by using a catalyst layer that is thicker on the cathode side than that on the anode side. Finally, a topological optimization of the platinum density within the cathode catalyst layer was performed with a gradient based algorithm, and the results showed that at a high stoichiometric ratio, the best design has most of its platinum placed where the reaction rate is the highest, i.e., close to the membrane layer. 相似文献
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Bert J. Campo David Bevk Jurgen Kesters Jan Gilot Henk J. Bolink Jun Zhao Jean-Christophe Bolsée Wibren D. Oosterbaan Sabine Bertho Jan D’Haen Jean Manca Laurence Lutsen Guy Van Assche Wouter Maes René A.J. Janssen Dirk Vanderzande 《Organic Electronics》2013,14(2):523-534
The introduction of functional moieties in the donor polymer (side chains) offers a potential pathway toward selective modification of the nanomorphology of conjugated polymer:fullerene active layer blends applied in bulk heterojunction organic photovoltaics, pursuing morphology control and solar cell stability. For this purpose, two types of poly(3-alkylthiophene) random copolymers, incorporating different amounts (10/30/50%) of ester-functionalized side chains, were efficiently synthesized using the Rieke method. The solar cell performance of the functionalized copolymers was evaluated and compared to the pristine P3HT:PCBM system. It was observed that the physicochemical and opto-electronic characteristics of the polythiophene donor material can be modified to a certain extent via copolymerization without (too much) jeopardizing the OPV efficiency, as far as the functionalized side chains are introduced in a moderate ratio (<30%) and that preference is given to side chains with a small molar volume. A range of complementary techniques – UV–Vis spectroscopy, (modulated temperature) differential scanning calorimetry, transmission electron microscopy and X-ray diffraction analysis – indicated that variations in polymer crystallinity, while maintaining a high level of regioregularity, are probably the main factor responsible for the observed differences. 相似文献
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Louis Sica 《Journal of Modern Optics》2013,60(16-18):2461-2468
Abstract Violation of Bell inequalities is widely regarded as a definitive test for non-locality. However, Bell correlational inequalities must always be satisfied by all jointly present, cross-correlated data. The correlations of variable pairs obtained in repeated runs are not cross-correlated in this way and are not required to satisfy the Bell inequality. In addition, by using information regarded as non-local, proper joint correlations may be computed among counterfactual and measured variables. These correlations satisfy the Bell inequality, but are spatially non-stationary in angle. By using a simple symmetry condition, such considerations may be extended to inequalities in probabilities. The latter may be derived directly from correlational inequalities developed by Clauser, Horne, Shimony and Holt (CHSH). Violation of either correlational or probabilistic Bell inequalities then implies that the Bell correlation cannot be accounted for by a stochastic process that is spatially stationary in angle coordinates. However, other processes may still be allowed. 相似文献
100.