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到家之后,利用家里的大屏幕电视无疑更能发挥视频的震撼效果。我们需要什么设备?是最近炒得火热的电视盒子?还是利用手头不用的笔记本电脑?或者DIY一台小巧精致的HTPC?要不就干脆直接购买智能电视?电视的视频最佳搭档,究竟是谁? 相似文献
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Jerzy Jedlinski Jean Luc Grosseau Poussard Jarosław Dabek Kazimierz Kowalski Marek Nocun Grzegorz Smola Zbigniew Żurek 《Oxidation of Metals》2017,88(3-4):371-382
The very early stages of the oxidation of an Fe20Cr2Al alloy, unmodified and ion-implanted by aluminium, yttrium and a combination of both elements, Al and Y, were studied at 1100 °C in oxygen using two-stage-oxidation exposures with 18O2 as a tracer and subsequent characterisation of the scales using SIMS analyses of distribution of oxygen isotopes and oxide-related negative ion clusters, SEM observations of the surface morphology and photoluminescence spectroscopy analysis of the phase composition. The scales formed in all cases, except for the Al-implanted alloy, exhibited layered structures, with the outer part comprising Fe- and Cr-rich oxide, and the inner part being Al2O3, which grew due to a mixed outward–inward mechanism . The alumina sub-layers contained the transient oxides and α-Al2O3. Implanted Al significantly affected the mechanism of the scale growth, providing that the scale consisted essentially of α-Al2O3, and grew via a mixed inward-outward mechanism typical for scales on alumina formers. 相似文献
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A sequence S is nonrepetitive if no two adjacent blocks of S are the same. In 1906 Thue proved that there exist arbitrarily long nonrepetitive sequences over 3 symbols. We consider the online variant of this result in which a nonrepetitive sequence is constructed during a play between two players: Bob is choosing a position in a sequence and Alice is inserting a symbol on that position taken from a fixed set A. The goal of Bob is to force Alice to create a repetition, and if he succeeds, then the game stops. The goal of Alice is naturally to avoid that and thereby to construct a nonrepetitive sequence of any given length.We prove that Alice has a strategy to play arbitrarily long provided the size of the set A is at least 12. This is the online version of the theorem of Thue. The proof is based on nonrepetitive colorings of outerplanar graphs. On the other hand, one can prove that even over 4 symbols Alice has no chance to play for too long. The minimum size of the set of symbols needed for the online version of Thue?s theorem remains unknown. 相似文献
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Susanne Struck Doris Jaros Charles S. Brennan Harald Rohm 《International Journal of Food Science & Technology》2014,49(9):1963-1976
This review presents the state‐of‐the‐art concerning the application of natural and artificial high‐intensity sweeteners, fructans and bulking agents such as polyols as sugar replacers in sweet‐baked goods and their effects on product characteristics. The recent much publicised attention given to weight gain of the population and its consequences on the occurrence of diet‐related diseases in developed countries has influenced the food manufacturers attempts to provide the consumer with reduced energy products. The replacement of sucrose in sweet bakery products by alternative natural or artificial sweeteners can be a challenging issue. Sucrose as a main ingredient in sweet bakery products contributes, aside from providing sweetness, to numerous processing and product characteristics. Intense sweeteners have a high sweetness compared with sucrose but lack in their contribution to the body of the product, whereas the replacement of sucrose with bulking sweeteners may result in products with a similar body but a lack in taste and flavour. 相似文献
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