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Distribution of phenol between aqueous and organic phases at maximal dilution in the range 283–328 K was studied chromatographically. Ten systems containing saturated and aromatic hydrocarbons were examined.Translated from Zhurnal Prikladnoi Khimii, Vol. 77, No. 11, 2004, pp. 1768–1771.Original Russian Text Copyright © 2004 by Dobryakova, Dobryakov.  相似文献   
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A program is composed to simulate the ESR spectra of Mn2+ ions (S = 5/2, J = 5/2) in polycrystalline samples at X- and Q-band frequencies taking into account nonvanishing HFS eigenwidth and the 3-rd order terms of perturbation theory for cubic crystalline field with a small axial distortion (Dg β H). Only the lines of allowed transitions (ΔM = ± 1, Δm = 0) have been considered. The probability of various HFS transitions was assumed to be the same and independent of orientation. The resonance field value Hm(θ) was determined for every component. The form of the ESR spectrum of the Mn2+ ion in a polycrystalline sample was found to depend strongly on interrelations between ΔHi, D, and H0. The analysis of the calculated spectra permits to estimate the value of D. A comparison was made between the calculated and experimental spectra of Mn2+ ion in powdered calcite. The theoretical spectrum with the parameters A = −93.5 Oe, D = 85.5 Oe, and Δ Hi, = 2.5 Oe was found to show all the peculiarities of the experimental spectrum.  相似文献   
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Procedures are developed for determining volatile sulfur-containing impurities, hydrogen sulfide, simple mercaptans, sulfides, and disulfides in air and aqueous solutions. The procedures are based on the principle’s headspace gas chromatography and equilibrium preconcentration. The procedures differ from the officially approved ones in that the operations of sampling and sample preparation to gas-chromatographic analysis considerably reduce the loss of hydrogen sulfide and mercaptans unstable in humid air. The procedures provide the determination of sulfur-containing substances at the level of their maximum permissible concentrations (MPC) in industrial emissions and natural waters and the analytical range of four orders of magnitude; they can be implemented on gas chromatographs with flame ionization and flame photometric detectors, a quartz capillary column, and a thermostated gas-sampling valve.  相似文献   
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The feasibility of an experimental study of small superconducting clusters (SC) is analyzed. Critical sizes for SC are calculated. Oscillations of the energy gap and the diamagnetic susceptibility of SC are considered.  相似文献   
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