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41.
42.
A. N. Vasyanin O. S. Kudryashova S. F. Kudryashov L. P. Filippova 《Russian Journal of Inorganic Chemistry》2006,51(1):131-142
The solubility in the water-salt quaternary reciprocal system Na2Cr2O7 + 2NH4Cl ⇆ (NH4)2Cr2O7 + 2NaCl-H2O has been investigated for the first time at 25, 50, and 75°C. Using a formal analytical model, the boundaries of the phase
fields have been determined, and the univariant lines and invariant points have been calculated. The experimental data have
been used to calculate the temperature and concentration parameters of the circular isohydric process of potassium dichromate
preparation with the participation of ammonium salts as intermediates. 相似文献
43.
V. I. Pavlovsky S. Yu. Bachinskii N. A. Tkachuk S. Yu. Makan S. A. Andronati Yu. A. Simonov I. G. Filippova M. Gdaniec 《Chemistry of Heterocyclic Compounds》2007,43(8):1029-1037
The condensation of 5-aryl-7-bromo-1,2-dihydro-3H-1,4-benzodiazepin-2-ones with aromatic aldehydes gives 5-aryl-3-arylidene-and
5-aryl-7-bromo-3-hetarylidene-1,2-dihydro-3H-1,4-benzodiazepin-2-ones. X-ray diffraction structural analysis yielded the molecular
and crystal structures of 7-bromo-3-(4′-methoxybenzylidene)-5-phenyl-1,2-dihydro-3H-1,4-diazepin-2-one and showed that this
compound has cis configuration. Radioligand analysis was used to study the affinity of these products toward central nervous
system and peripheral benzodiazepine receptors.
__________
Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 8, pp. 1213–1225, August, 2007. 相似文献
44.
Thermal deformations and phase transformations of evennumbered paraffins CnH2n+2(n=20, 22, and 24) have been investigated in a thermal X-ray diffraction study. In homologs with n=20 and 24, phase transformations
occur in two steps: triclinic-to-orthorhombic and orthorhombic-to-hexagonal transitions. An orthorhombic rotator phase of
even n-paraffins is described for the first time. A crystal-chemical model of the phase transformations of the homologs is
suggested.
St. Petersburg State University. Translated fromZhurnal Strukturmoi Khimii, Vol. 36, No. 5, pp. 790–798, September–October, 1995.
Translated by L. Smolina 相似文献
45.
T. M. Filippova S. D. Mikhno N. S. Kulachkina I. G. Suchkova V. M. Berezovskii 《Chemistry of Heterocyclic Compounds》1981,17(12):1174-1178
The chemical shifts and the direct carbon-proton spin-spin coupling constants for a number of cis and trans isomers of 4-amino-substituted 3-hydroxy(acyloxy)-thiophans, the configurations of the substituents in which and the conformational states were previously established by an independent method, were studied. It was found that in the spectra of the cis isomers the signals of the vicinal 13C atoms, which bear the substituents, are shifted to strong field as compared with the trans isomers ( trans-cis 1.7–4.3 ppm). Conformational effects of the substituents on the chemical shifts of the ring 13C atoms were noted. It is shown that a relationship exists between the direct carbon-proton spin-spin coupling constants and the spatial orientations of the acyloxy and acylamino substituents for five-membered saturated rings.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 12, pp. 1612–1616, December, 1981. 相似文献
46.
Yuzefovich L. Yu. Sheiman B. M. Filippova T. M. Mairanovskii V. G. 《Chemistry of Heterocyclic Compounds》1978,14(6):617-622
The kinetics of the ring—chain tautomeric equilibria of a number of p-substituted 2,3,3-trimethyl-1-aryl-2-hydroxy-5-pyrrolidones in 50% aqueous pyridine were studied by dynamic PMR spectroscopy, and the effect of substituents on the kinetic parameters of this process was determined. The free energies of activation (G) decrease regularly on passing from electron-donor to electron-acceptor substituents. A good correlation between G and the + and substituent constants is observed. On the basis of the data obtained, it was concluded that the ratedetermining step in the process is detachment of a proton under the influence of the base to give the corresponding anion.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 6, pp. 758–763, June, 1978. 相似文献
47.
G. Bouyoucos E. H. Reinau W. Shaw C. J. Schollenberger E. Jung H. Biltz W. Biltz K. Nehring S. Katakousinos A. Papadimitriou P. Pfeffer I. N. Antipov-Karatajev V. N. Filippova N. Bengtsson G. S. Fraps A. J. Sterges A. Némec und Anna Koppová 《Fresenius' Journal of Analytical Chemistry》1935,101(7-8):301-306
Ohne Zusammenfassung 相似文献
48.
49.
Alaverdian L Alaverdian S Bilenko O Bogdanov I Filippova E Gavrilov D Gorbovitski B Gouzman M Gudkov G Domratchev S Kosobokova O Lifshitz N Luryi S Ruskovoloshin V Stepoukhovitch A Tcherevishnick M Tyshko G Gorfinkel V 《Electrophoresis》2002,23(16):2804-2817
We have developed a family of high-performance capillary DNA sequencing instruments based on a novel multicolor fluorescent detection technology. This technology is based on two technical innovations: the multilaser excitation of fluorescence of labeled DNA fragments and the "color-blind" single-photon detection of modulated fluorescence. Our machines employ modern digital and broadband techniques that are essential for achieving superior instrument performance. We discuss the design and testing results for several versions of the automated single lane DNA sequencers, as well as our approach to scaling up to multilane instruments. 相似文献
50.
A difference in the electromagnetic properties of D2O and H2O ice revealed by resonance measurements
The dielectric parameters of H2O and D2O ice samples were studied by a resonance technique in the region of 6 GHz. The ratio of the resonance curve halfwidths at half maximum was measured for light and heavy ice in the temperature range from 0 to ?130°C. The temperature dependences of the resonance peak asymmetry of the two types of ice are qualitatively different. The ratio of the higher-frequency halfwidths at half maximum to the lower-frequency one plotted versus temperature exhibits a positive slope for light ice and a negative slope for heavy ice. It is suggested that the difference reflects the different quantum statistics of the hydrogen and deuterium nuclei in ice. 相似文献