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Gennady P. Berman Alan R. Bishop Boris M. Chernobrod Dinh C. Nguyen Vyacheslav N. Gorshkov 《Optics Communications》2007,280(2):264-270
A new concept of a free space, high-speed (Gbps) optical communication system based on spectral encoding of radiation from a broadband pulsed laser is developed. It is shown that, in combination with the use of partially coherent laser beams and a relatively slow photosensor, scintillations can be suppressed by orders of magnitude for distances of more than 10 km. 相似文献
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In this paper we discuss a class of numerical algorithms termed one-leg methods. This concept was introduced by Dahlquist in 1975 with the purpose of studying nonlinear stability properties of multistep methods for ordinary differential equations. Later, it was found out that these methods are themselves suitable for numerical integration because of good stability. Here, we investigate one-leg formulas on nonuniform grids. We prove that there exist zero-stable one-leg variable-coefficient methods at least up to order 11 and give examples of two-step methods of orders 2 and 3. In this paper we also develop local and global error estimation techniques for one-leg methods and implement them with the local–global step size selection suggested by Kulikov and Shindin in 1999. The goal of this error control is to obtain automatically numerical solutions for any reasonable accuracy set by the user. We show that the error control is more complicated in one-leg methods, especially when applied to stiff problems. Thus, we adapt our local–global step size selection strategy to one-leg methods. 相似文献
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Oleg V. Bityukov Vera A. Vil George K. Sazonov Andrey S. Kirillov Nikita V. Lukashin Gennady I. Nikishin Alexander O. Terentev 《Tetrahedron letters》2019,60(13):920-924
It was discovered that the Kharasch peroxidation of barbituric acids proceeds both with a Cu-catalyst and without a metal catalyst. Despite the presence of possible thermal-initiated side oxidation pathways, α-tert-butylperoxybarbiturates were selectively prepared from substituted barbituric acids and tert-butyl hydroperoxide. 相似文献
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G.A. Evtugyn S.V. Belyakova A.A. Saveliev E.E. Stoikova I.I. Stoikov H.C. Budnikov 《Talanta》2010,82(2):613-574
Solid-contact ion-selective electrodes based on glassy carbon electrode covered with electropolymerized polyaniline and tetrasubstituted thiacalix[4]arene ionophores with hexyl and o-pyridylamido functional groups at the lower rim have been developed and examined in the discrimination of the brands of apple juices and herbal liqueurs. For this purpose, the liquids tested were diluted and spiked with a constant amount of Fe3+ ions. The variation of the signal toward Fe3+ ions was achieved due to their involvement in the reactions with the organic ligands and the antioxidants present. As was shown, the combination of the three electrodes with various receptors makes it possible to predict the brand of apple juices and herbal liqueurs using linear discriminant analysis in 95-100% cases. The discrimination procedure makes it possible to discriminate liquids within 20 min. Besides, the electrodes developed make it possible to detect individual antioxidants (ascorbic, malic, oxalic acids, hydroquinone, and quercetin) in the range from 5.0 × 10−6 to 1.0 × 10−2 M in direct potentiometric measurements and redox titration. 相似文献
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