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1.
Summary Optically pure (+)-beta-eudesmol is a possible starting material for the synthesis of several termite defense compounds. A
two step procedure for the isolation of gram quantities of (+)-beta-eudesmol from commercially availableAmyris balsamifera oil (syn. West Indian sandalwood oil), containing 8% beta-eudesmol, was developed. Step one consisted of an efficient vacuum
distillation of the total oil. Step two was a medium pressure LC separation with an AgNO3 impregnated silica gel stationary phase. Several other separation procedures failed due to the presence of many closely related
sesquiterpene alcohols (75% of the oil). 相似文献
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Travkin V. F. Glubokov Yu. M. Mironova E. V. Yakshin V. V. 《Russian Journal of Applied Chemistry》2001,74(10):1664-1667
The effects of the concentrations of sulfuric acid and arsenic in the aqueous phase, concentration of the extractant in the organic phase, temperature, and time of phase contact on arsenic(V) extraction with hexabutylphosphoric triamide were studied, and the arsenic(V) extraction constant was calculated. 相似文献
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Medvedev VV Yakshin AE van de Kruijs RW Krivtsun VM Yakunin AM Koshelev KN Bijkerk F 《Optics letters》2012,37(7):1169-1171
An extreme ultraviolet multilayer mirror with an integrated spectral filter for the IR range is presented and experimentally evaluated. The system consists of an IR-transparent B4C/Si multilayer stack which is used both as EUV-reflective coating and as a phase shift layer of the resonant IR antireflective (AR) coating. The AR coating is optimized in our particular case to suppress CO2 laser radiation at a wavelength of 10.6 μm, and a suppression of more than two orders of magnitude is demonstrated. The method allows high suppression over a large angular acceptance range, relevant for application in lithography systems. 相似文献
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Kaganovich Boris M. Zarodnyuk Maxim S. Yakshin Sergey V. 《Journal of Thermal Analysis and Calorimetry》2018,133(2):1225-1232
Journal of Thermal Analysis and Calorimetry - The paper is concerned with the problem of macroscopic (unrelated with probability theory) construction of trajectories of irreversible physicochemical... 相似文献
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V. V. Yakshin O. N. Vilkova N. A. Tsarenko S. V. Demin V. I. Zhilov A. Yu. Tsivadze 《Russian Journal of Coordination Chemistry》2006,32(2):77-81
The distribution coefficients of the alkaline and alkali-earth metal nitrates are determined for the processes of extraction from nitric acid solutions with crown ethers, which differ in sizes of their cycles (from 18 to 22 atoms) and in side phenyl and cyclohexyl substituents, but have unchanged number of the O atoms in a cycle. The phenyl and cyclohexyl derivatives of 18-crown-6 are found to be more efficient extractants of alkali metals as compared with unsubstituted crown ethers. However, the selectivity of separation of a pair Cs-Na remains low. The 18-crown-6 derivatives with one and two cyclohexyl fragments selectively extract Sr, which can be used to separate it from the remaining alkali and alkaline-earth metals. An increase in the size of a macrocycle from 18 to 20 and 22 atoms leads to a reduction in the extraction efficiency for all alkali and alkaline-earth metals, insignificantly improves separation of a pair Cs-Na, but noticeably deteriorates Sr-Na separation. 相似文献
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