Study of binary systems of long chain alcohols and acids

1974 ◽  
Vol 51 (5) ◽  
pp. 229-233 ◽  
Author(s):  
M. A. Al-Mamun
Keyword(s):  
2013 ◽  
Vol 63 ◽  
pp. 108-115 ◽  
Author(s):  
A. Bagheri ◽  
A. Abolhasani ◽  
A.R. Moghadasi ◽  
A.A. Nazari-Moghaddam ◽  
S.A. Alavi

1949 ◽  
Vol 2 (3) ◽  
pp. 405
Author(s):  
RL Meakins

Experimental work on the dielectric properties of solid systems of long-chain polar and non-polar compounds has been performed by Jackson(l), Sillars(2), and Pelmore(3) with dilute solutions of esters in paraffin wax. In subsequent theoretical studies in this field Fr�hlich(4) adopted, as a model, a crystalline long-chain paraffin in which a small proportion of the molecules were assumed to be replaced by long-chain polar molecules. Taking Debye's theory of dielectric absorption in polar solids as a basis, this led to the derivation of a relationship between the relaxation time and the number of links in the polar molecule. In order to obtain experimental results more closely related to the theory, electrical measurements have now been made with symmetrical long-chain ketones in pure crystalline hydrocarbon solvents. The variation of dielectric constant and loss angle with frequency for these systems is found to be approximately in agreement with the Debye theory of dielectric absorption. For ketones of chain-length shorter than that of the hydrocarbon solvent the relationship between relaxation time and chain-length is of the type expected from Fr�hlich's theory, but displaced towards lower frequencies. The results show that, in applying the theoretical relationship to systems of long-chain polar and non-polar compounds, it would be necessary to determine new constants for each different type of polar compound and for each different solvent. The results of electrical measurements of ketone-hydrocarbon systems with ketones of varying chain-length (both less and greater than that of the solvent) are in accordance with conclusions from previous X-ray studies of long-chain hydrocarbons. The effects of dipole interaction on the dielectric absorption of systems of laurone and n-hexacosane, are discussed in relation to the solid-liquid phase diagram. The results of dielectric measurements with pure crystalline compounds suggest that dipole interaction and electrical cooperative effects are larger in ketones than in esters of similar chain-length.


1965 ◽  
Vol 5 ◽  
pp. 120-130
Author(s):  
T. S. Galkina

It is necessary to have quantitative estimates of the intensity of lines (both absorption and emission) to obtain the physical parameters of the atmosphere of components.Some years ago at the Crimean observatory we began the spectroscopic investigation of close binary systems of the early spectral type with components WR, Of, O, B to try and obtain more quantitative information from the study of the spectra of the components.


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