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921.
922.
M. F. Bundule A. F. Mishnev V. K. Lusis D. Kh. Mutsenietse A. Z. Zandersons G. Ya. Dubur 《Chemistry of Heterocyclic Compounds》1991,27(9):995-998
The molecular crystal structure of 4-phenyl-3,5-diethoxycarbonyl-1,2,6-trimethyl-1,2-dihydropyridine has been investigated by x-ray structural analysis. The three-dimensional structural properties of the molecule have been compared against the large observed reactivity of the 3-ethoxycarbonyl group with respect to nucleophilic substitution reactions.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 9, pp. 1236–1239, September, 1991. 相似文献
923.
A single isomer of a monofunctionalised C70 fullerene is isolated and characterised using variable temperature NMR spectroscopy. Pendant methylene bromide groups allow for further cycloaddition reactions and a C60-C70 asymmetric fullerene dimer is thus prepared. 相似文献
924.
The anti-Parkinson’s agent SIB-1508Y was prepared in six steps from (S)-nicotine in 20% overall yield. The strategy involves a regioselective formylation at C-5 of a 1,4-dihydronicotine intermediate. 相似文献
925.
The synthesis of chiral oxazolidinedione derived bicalutamide analogs has been discussed. 相似文献
926.
Specific features of the formation of local and statistical polarization structures of laser radiation scattered in phase-inhomogeneous layers (PIL) of biological tissue (BT) were studied. The distribution of azimuth and eccentricity of boundary field polarization was found to correlate with the orientation-phase structure of multifractal PIL. A method of polarization phase reconstruction of BT architectonics was suggested. 相似文献
927.
F. Kulcsár D. Teherani H. Altmann 《Journal of Radioanalytical and Nuclear Chemistry》1982,68(1-2):161-168
It is pessible to study experimentally Cherenkov light spectra in a liquid scintillation spectrometer with colour filters.
Cherenkov light spectra of60Co,198Au,115Cd,143Ce,140La,32P,86Rb,76As,42K and an external standard were studied in a Packard 3375 type liquid scintillation spectrometer, using 11 various Kodak Wratten
filters. The absorption maxima of the filters ware in the 410–796 nm interval. 相似文献
928.
T. Gühne V. Gottschalch G. Leibiger H. Herrnberger J. Kovác J. Kovác Jr. R. Schmidt-Grund B. Rheinländer D. Pudis 《Laser Physics》2006,16(3):441-446
In this paper, we report on the design and optical properties of laser diodes with an emission wave-length of ~1170 nm based on an (InGa)As/GaAs double quantum well active layer. The back and front facet of the laser diodes were coated with SiOx dielectric films that influence the output optical power by enhancing or lowering the facet reflectivity. The measurements show improvement of the facet-coated laser diode properties in the threshold-current-density reduction along with light output power enhancement. Furthermore, a narrow far field pattern and high side mode suppression have been observed. 相似文献
929.
930.