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1.
V. I. Evreinov V. E. Baulin Z. N. Vostroknutova Z. V. Safronova I. B. Krashakova V. Kh. Syundyukova E. N. Tsvetkov 《Russian Chemical Bulletin》1991,40(9):1759-1766
Stability constants of complexes of alkali-metal cations with oligoethylene glycol diethers RO(CH2CH2O)nR (n=1–5), where R=2-Ph2P(O)C6H4 and 2-Ph2(O)-4-t-BuC6H3P, have been determined conductometrically in a tetrahydrofuran-chloroform mixture (41 by volume). The dependence of complexing ability on a number of monopodand donor centers for Li+ and Na+ has multiple extrema. For K+, Rb+, and Cs+ the complexing abilities steadily increase with the length of the ligand polyether chain. Monopodands based on triethylene glycol and its pyrocatechol analog are highly effective (log K=6.7–7.0) with respect to Li+. The synthesis of ligands with a lipophilic tert-butyl substituent in the terminal group is described.For previous communication, see [1]. The number of the communication in [2] is 5, not 4 as printed in error.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 9, pp. 1992–2000, September, 1991. 相似文献
2.
Conclusions Both the nucleophilic and the free radical addition of n-butyl mercaptan to acetylenic-hydroxy ketones (1,1-disubstituted derivatives of 2-pentyn-1-ol-4-one) lead to the formation of the corresponding 1,1-disubstituted derivatives of 2-butylthio-2-penten-1-ol-4-one in 41–65% yield.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 7, pp. 1669–1670, July, 1973. 相似文献
3.
G. I. Sarapulova M. V. Andreev L. P. Safronova A. S. Medvedeva 《Russian Journal of Organic Chemistry》2001,37(12):1688-1692
The specific features of molecular and electronic structure of trimethylsilylpropiolic acid amides were studied by means of IR spectroscopy and quantum chemistry (AM1). The competition between p,-conjugation in the amide fragment and ,-conjugation in the ethynylcarbonyl group CC-C=O was established. The prevailing conformers were revealed, their geometrical parameters were established, the barriers to internal rotation around the amide C-N bond were calculated for acyclic (13 kcal mol-1) and heterocyclic (8.12 kcal mol-1) amides. 相似文献
4.
On the basis of the S-matrix approach, a theory of perturbations in 1/Z is developed; the energy of a multielectron system is written in the form of a double series in powers of andZ and a method of determining the coefficients of this series in a j-j coupling scheme is given. The method is applied to configurations of the type
, and numerical results are given for the wavelength of transitions between several states of the isoelectronic as sequence of carbon, illustrating the good agreement between experiment and theory.Translated from Izvestiya Vysshikh Uchebnikh Zavedenii, Fizika, No. 8, pp. 59–63, August, 1978. 相似文献
5.
U. I. Safronova A. N. Ivanova V. N. Kharitonova 《Theoretical and Experimental Chemistry》1969,5(3):209-216
Transition probabilities and oscillator strengths are calculated for the configurations 1s2 2sn1 and 1s2 2sn1-1 2pn2+1, which are, respectively, of the form P=a/Z (1+/Z+) andf=/Z (1+/Z+). Numerical values are given fora, ,, and. 相似文献
6.
It is shown that the near order in the relative position of different types of atoms is preserved in a Mg-In (30 at.% In) solid solution at temperatures close to the melting point. Diffuse scattering from this alloy is measured in a Cu K irradiated high-temperature vacuum chamber. The diffusion maximum in the region of the first superlattice lines decreases in intensity with increasing temperature. The tape diffraction pattern shows that at 440C the structure lines become a blurred scattering maximum, similar to that observed in any liquid or amorphous body. A rather intense maximum is simultaneously observed at the same angles at which the maximum due to the near order in a solid solution is observed.Translated from Izvestiya Uysshikh Uchebnykh Zavedenii, Fizika, No. 1, 18–22, January, 1976. 相似文献
7.
A. N. Yarkevich Z. V. Safronova L. N. Petrova A. V. Gabrelyan V. L. Zamoyski V. V. Grigor’ev S. O. Bachurin N. S. Zefirov 《Russian Journal of General Chemistry》2013,83(1):41-45
Bis(dialkylamides) of phosphoryl-substituted α,ω-dicarboxylic acids were synthesized and their biological activity was studied. 相似文献
8.
M. Yu. Artyushenko A. A. Baldin A. I. Berlev O. V. Bukhal V. A. Voronko K. V. Gusak I. V. Zhuk I. V. Kudashkin M. Paraipan A. S. Potapenko A. A. Safronova V. V. Sotnikov S. I. Tyutyunnikov 《Physics of Particles and Nuclei Letters》2016,13(4):466-470
The cross sections for the spallation of the heavy-metal nuclei 181Ta, 197Au, 207Pb, 209Bi, 232Th, and 238U induced by relativistic deuterons with energies of 2, 2.94, and 3.5 GeV per nucleon are measured using the deuteron beam from the Nuclotron accelerator of the JINR Laboratory of High Energy Physics in Dubna, Russia. The cross-section measurements employ a combined experimental technique involving the solidstate nuclear-track detectors and the activation gamma spectrometry. Adding our measurements to the database of experimental nuclear data will make it possible to test the computer codes used for selecting the parameters of the ADS-type facilities. 相似文献
9.
10.
We discuss the notion of spin squeezing considering two mutually exclusive classes of spin-s states, namely, oriented and non-oriented states. Our analysis shows that the oriented states are not squeezed while non-oriented
states exhibit squeezing. We also present a new scheme for construction of spin-s states using 2s spinors oriented along different axes. Taking the case of s=1, we show that the ‘non-oriented’ nature and hence squeezing arise from the intrinsic quantum correlations that exist among
the spinors in the coupled state. 相似文献