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921.
922.
A. A. Berlin I. A. Novakov A. Ya. Lyapunov A. V. Nistratov E. N. Titova L. S. Bekhli S. Yu. Gugina D. V. Pyl’nov 《Polymer Science Series D》2012,5(3):133-137
The results of an investigation of the influence of stillage residues of polyfluorinated alcoholtelomeres on the properties of polydienurethane compositions and elastomers based on them are presented. It is shown that such modification allows one to raise the sedimentation stability of the compositions and increase the characteristics of physicochemical and dynamic properties of elastomers. 相似文献
923.
A semi-empirical method is proposed to calculate the ion ranges in energy region E?=?0.025–10?MeV/nucleon. The dependence of ion ranges on the projectile nuclear charge, mass and velocity is analysed. The calculations presented for ranges of ions with nuclear charges Z?=?2–10 in silicon are compared with SRIM results and experimental data. 相似文献
924.
A. G. Touryanskiy S. S. Gizha V. M. Senkov Ya. M. Stanishevskiy 《Bulletin of the Russian Academy of Sciences: Physics》2018,82(4):369-371
An energy-dispersive scheme using a bandpass filter based on pyrolytic graphite is proposed for determining the content of heavy elements from X-ray absorption spectra. The detected excitation spectrum is corrected to increase the accuracy of measurement. The initial shape of the photoabsorption jump is reconstructed in the approximation of an isolated atom by numerically solving the convolution equation. 相似文献
925.
926.
927.
Xiao‐Ya Yuan 《合成通讯》2013,43(8):1057-1062
A new enantiopure 6‐monobromo‐substituted BINAP has been prepared via a one‐step nickel‐catalyzed coupling reaction in moderate yield. It is an important intermediate for asymmetric 2,2′‐bis(diphenylphosphino)‐1,1′‐binaphthyl (BINAP) derivatives. Its structure was elucidated by NMR spectral and elemental analysis. 相似文献
928.
1,4-Nucleophilic addition reactions of 3-nitrothiochromone with indoles gave a number of novel trans-2-(indol-3-yl)-3-nitrothiochroman-4-ones in 36–89% yields. During the reactions, the thiopyrone ring underwent no opening. 相似文献
929.
Co (II)‐C12 alkyl carbon chain multi‐functional ionic liquid immobilized on nano‐SiO2 nano‐SiO2@CoCl3‐C12IL as an efficient cooperative catalyst for C–H activation by direct acylation of aryl halides with aldehydes
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Nano‐silica supported ionic liquids composed of alkyl carbon chain and transition metal chlorides anions have been prepared and successfully applied as a heterogeneous catalyst in the direct aldehyde C‐H activation. Catalytic results indicated that nano‐SiO2 supported ionic liquid consisting C12 alkyl carbon chain and CoCl3 anion nano‐SiO2@CoCl3‐C12IL showed excellent catalytic properties with good to excellent yields towards the desired aryl ketones. The excellent recyclability of the supported catalyst, mild reaction conditions, low catalyst loading, and operational simplicity are the important features of this methodology. 相似文献
930.
Baulina Т. V. Kudryavtsev I. Yu. Sykat G. Ya. Brel’ V. K. 《Russian Journal of General Chemistry》2018,88(9):1927-1930
Russian Journal of General Chemistry - A series of precursors of novel tripodal ligands (2-XCH2CH2CH2OC6H4)3PO, where X = AcO, HO, MeSO2O, Br, N3, were synthesized by the alkylation of the starting... 相似文献