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61.
Felix Waldmeier Silvio De Bernardini Colin A. Leach Christoph Tamm 《Helvetica chimica acta》1982,65(8):2472-2475
Zinc bromide has been shown by several groups of workers to be a useful reagent in the removal of trityl protecting groups from nucleotides. An attempt is made here to establish optimum conditions for the reaction, a strange observation is reported, and a novel workup via a soluble, lipophilic zinc complex is described. 相似文献
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64.
Vats Bal Govind Pius I. C. Noronha D. M. Kannan S. 《Journal of Radioanalytical and Nuclear Chemistry》2018,317(1):227-234
Journal of Radioanalytical and Nuclear Chemistry - A new approach for the extraction of plutonium and americium from aqueous media containing complexing ligands has been investigated using a new... 相似文献
65.
The hydrothermal reactions of uranium trioxide, uranyl acetate, or uranyl nitrate with 1,4-benzenebisphosphonic acid in the presence of very small amount of HF at 200 °C results in the formation of three different uranyl diphosphonate compounds, [H3O]2{(UO2)6[C6H4(PO3)(PO2OH)]2[C6H4(PO2OH)2]2[C6H4(PO3)2]}(H2O)2 (Ubbp-1), [H3O]4{(UO2)4[C6H4(PO3)2]2F4}·H2O (Ubbp-2), and {(UO2)[C6H2F2(PO2OH)2(H2O)}2·H2O (Ubbp-3). The crystal structures of these compounds were determined by single crystal X-ray diffraction experiments. Ubbp-1 consists of UO7 pentagonal bipyramids that are bridged by the phosphonate moieties to form a three-dimensional pillared structure. Ubbp-2 is composed of UO5F2 pentagonal bipyramids that are bridged through the phosphonate oxygen atoms into one-dimensional chains that are cross-linked by the phenyl spacers into a pillared structure. The structure of Ubbp-3 is a three-dimensional open-framework with large channels containing water molecules with internal dimensions of approximately 10.9×10.9 Å. Ubbp-1 and Ubbp-2 fluoresce at room temperature. 相似文献
66.
Secure transmission in wireless networks is a big critical issue due to the broadcast nature of the wireless propagation environment. In this paper, the physical layer security performance in a mixed radio frequency (RF)/free space optical (FSO) system under multiple eavesdroppers is investigated. The RF links and FSO link within the system are assumed to respectively undergo Nakagami-m and Gamma–Gamma fading distributions. The two practical eavesdroppers scenarios considered includes: Colluding and Non-colluding in which their channel state information is unavailable at the source. The closed-form expressions for the lower bound security outage probability and the strictly positive secrecy capacity under both scenarios are derived by utilizing the system end-to-end cumulative distribution function and eavesdroppers’ probability density function. The results show that the increase in the number of eavesdroppers under both scenarios profoundly degrades the system secrecy performance. Moreover, it is demonstrated that both the atmospheric turbulence and pointing errors affect the concerned system secrecy and the impact of RF fading parameters is also presented. The accuracy of the numerical results obtained is validated by Montel-Carol simulations. 相似文献