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961.
Matthew P. Aldred Miguel Carrasco-Orozco Adam E. A. Contoret Dewen Dong Simon R. Farrar Stephen M. Kelly Stuart P. Kitney Dean Mathieson Mary O'Neill W. Chung Tsoi Panos Vlachos 《Liquid crystals》2006,33(4):459-467
We report the synthesis of a red light-emitting and photopolymerizable smectic liquid crystal (reactive mesogen). We investigate the suitability of polymer networks formed from smectic reactive mesogens for use in organic light-emitting diodes (OLEDs). The use of mixtures of smectic reactive mesogens is shown to lower the processing temperature for the fabrication of OLEDs to room temperature. We also report efficient energy transfer from a nematic polymer network host to a smectic light-emitting dopant and polarized emission from a polymer network formed from an aligned smectic reactive mesogen. 相似文献
962.
Melissa A. Denecke Boris Brendebach Wout De Nolf Gerald Falkenberg Koen Janssens Rolf Simon 《Spectrochimica Acta Part B: Atomic Spectroscopy》2009,64(8):791
Spatially resolved X-ray absorption and fluorescence investigation with a micrometer-scale resolution on actinide-containing samples provide information necessary for safety assessment of nuclear waste disposal. In this paper one example of such an experiment is presented. This example entails neptunium speciation in a fractured granite bore core from the Swedish Äspö Hard Rock Laboratory following a radiotracer experiment using µ-XAFS and µ-XRF. In order to probe micro-volumes below the surface in the granite samples and thereby avoid potential changes in the Np speciation during cutting of the bore core, a confocal irradiation–detection geometry is employed. µ-XAFS results for a selected granite bore core cross section with ~ 3 nmol Np/g reveal that Np, originally introduced as Np(V) in the tracer cocktail, is present in the granite in its reduced Np(IV) form. The Np(IV) is often present as particles, tens of µm in size. Elemental distribution maps show the tracer Np to be located in fissures and permeable channels not larger than 100 µm. The Np distribution appears often correlated with Zn also present in some fissures. We observe small granite fissures containing Fe (presumably Fe(II)), where we do not detect any Np. It is feasible that inflowing Np(V) has a shorter residence time in large fractures, while in the smaller fissures migration is slower, leading to longer residence times, i.e., reaction times, where it is reduced to less soluble Np(IV) and becomes thereby immobilized. 相似文献
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Let q be a power of a prime and n a positive integer. Let P(q) be a parabolic subgroup of the finite general linear group GL
n
(q). We show that the number of P(q)-conjugacy classes in GL
n
(q) is, as a function of q, a polynomial in q with integer coefficients. This answers a question of Alperin in (Commun. Algebra 34(3): 889–891, 2006) 相似文献
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