Kerr constant-dispersion measurements on benzene and carbon tetrachloride

1968 ◽  
Vol 21 (7) ◽  
pp. 1703 ◽  
Author(s):  
RJW Le Fevre ◽  
SC Solomons
Keyword(s):  
Carbon Tetrachloride ◽  
Kerr Constant ◽  
Empirical Equations ◽  
Kerr Constants

The electric birefringences displayed by the above two liquids have been measured photometrically at wavelengths between 375 and 625 mμ, and Kerr constants Bλ computed relatively to benzene, for which B589 is 0.410 x 10-7 at 25�. Empirical equations connecting Bλ values and refractive indexes with X are developed, and compared in applicability with others from the literature. Data necessary for the determination of molar Kerr constants of coloured solutes in the named solvents are also recorded.

scholarly journals Kerr constant-dispersion measurements on cyclohexane

1972 ◽  
Vol 25 (2) ◽  
pp. 413 ◽  
Author(s):  
FFvre RJW Le ◽  
RK Pierens
Keyword(s):  
Carbon Tetrachloride ◽  
Wavelength Range ◽  
Kerr Constant ◽  
Inert Medium ◽  
Chemical Changes ◽  
Kerr Constants ◽  
Hydrogen Bondings ◽  
Basic Substances

Le Fbre and Solomons recorded the Kerr constants Bγ of carbon tetrachloride and benzene over the wavelength range 375-625 nm to make possible the use of these solvents in examining the anisotropic polarizabilities of coloured solutes. Since, however, unsuspected hydrogen bondings may occur between π-electrons of benzene and protons from a dissolved molecule, and/or because of the various risks of chemical changes when basic substances are studied in carbon tetrachloride, an additional and more inert medium became desirable. Cyclohexane seemed to be the least reactive of the liquids which are available in quantity and easily purified, but no information on the variation of its B constant with wavelength was in the literature; the present measurements were therefore made to fill this gap.

Molecular susceptibility. The determination of molar Cotton-Mouton constants at infinite dilution in benzene or cyclohexane

1966 ◽  
Vol 19 (8) ◽  
pp. 1315 ◽  
Author(s):  
RJW Le Fevre ◽  
DSN Murthy
Keyword(s):  
Carbon Tetrachloride ◽  
Infinite Dilution ◽  
Empirical Equations

Reliable measurements of the small incremental Cotton-Mouton constants encountered at low solute concentrations with solutions in which the magnetic birefringences of solute and solvent do not differ widely cannot be made with equipment at present available. Five such systems are examined in this paper. It is shown that the larger incrementa easily observable among stronger solutions can be fitted to empirical equations containing ascending powers of the concentrations and hence estimates of ΔC/w2 as w2 approaches zero become accessible. Values of ∞(mC2) obtained by this device agree reasonably with others directly drawn from much weaker solutions of the same solutes in carbon tetrachloride or cyclohexane, i.e, in media for which C1 = 0.

Determination of Temperature Dependence of Kerr Constant for Nematic Liquid Crystal

2011 ◽  
Vol 544 (1) ◽  
pp. 227/[1215]-231/[1219] ◽  
Author(s):  
M. H. Majles Ara ◽  
S. H. Mousavi ◽  
M. Rafiee ◽  
M. S. Zakerhamidi
Keyword(s):  
Liquid Crystal ◽  
Temperature Dependence ◽  
Nematic Liquid Crystal ◽  
Kerr Constant

Dipole moments, Kerr constants and solution-state conformations of di(pyridin-4-yl), di(pyridin-3-yl) and di(pyridin-2-yl) ketone

1980 ◽  
Vol 33 (12) ◽  
pp. 2597 ◽  
Author(s):  
PH Gore ◽  
IG John ◽  
RK Pierens ◽  
GLD Ritchie
Keyword(s):  
Carbon Tetrachloride ◽  
Dipole Moments ◽  
Strong Preference ◽  
Trans Conformation ◽  
Solution State ◽  
Kerr Constants

Experimental dipole moments and molar Kerr constants are reported and analysed for di(pyridin-4-yl), di(pyridin-3-yl) and di(pyridin-2-yl) ketone as solutes in carbon tetrachloride or cyclohexane at 298 K. The preferred conformation of di(pyridin-4-yl) ketone is found to be very similar to those previously deduced for benzophenone and several 4,4'- disubstituted benzophenones. For di(pyridin-3-yl) and di(pyridin-2-yl) ketone three analogous conrotatory structures having different relative dispositions of the nitrogen atoms are considered. In the case of di(pyridin-3-yl) ketone the cis-trans and trans-trans arrangements are approximately equally abundant, but for di(pyridin-2-yl) ketone there is a strong preference for the trans-trans conformation.

Collaborative Study Using a ZDBT Colorimetric Method for the Determination of Copper in Alcoholic Products

1967 ◽  
Vol 50 (2) ◽  
pp. 334-338
Author(s):  
Duane H Strunk ◽  
A A Andreasen
Keyword(s):  
Sulfuric Acid ◽  
Carbon Tetrachloride ◽  
Collaborative Study ◽  
Colorimetric Method ◽  
Good Precision ◽  
Determination Of Copper

Abstract Results are given on a collaborative study in which a zinc dibenzyldithiocarbamate (ZDBT) colorimetric method is used to measure copper in alcoholic products such as high wine, spirits, gin, whisky, brandy, rum, and wine. In this method, the sample is made ca 0.SN with sulfuric acid, and carbon tetrachloride containing 0.2% ZDBT is added. The colored copper-ZDBT complex is extracted in the carbon tetrachloride and measured at 438 mμ against a similar carbon tetrachloride extract of a blank. Data show good precision, and it is recommended that the ZDBT method be adopted as official, first action.

Determination of Small Bone Particles in Meat

1968 ◽  
Vol 51 (6) ◽  
pp. 1175-1177 ◽  
Author(s):  
Robert M Hill ◽  
B D Hites
Keyword(s):  
Carbon Tetrachloride ◽  
Meat Products ◽  
The Other ◽  
Small Particles ◽  
Bone Content ◽  
Bone Particles ◽  
Small Bone ◽  
Good Agreement

Abstract Very small particles of bone can be separated from ground meats and meat products by the following procedure: The bulk of the meat is solubilized by digestion with papain and the bone is separated from the other nondigestible material according to its ability to settle in a carbon tetrachloride: acetone mixture. Turkey samples with widely varying bone content were analyzed, with good agreement between duplicate samples.

Improved Codistillation Method for Determination of Carbon Tetrachloride, Ethylene Dichloride, and Ethylene Dibromide in Grain and Grain-Based Products

1985 ◽  
Vol 68 (4) ◽  
pp. 759-762
Author(s):  
Jonathan W Devries ◽  
Paul A Larson ◽  
Raymond H Bowers ◽  
Joyce A Keating ◽  
James M Broge ◽  
...  
Keyword(s):  
Carbon Tetrachloride ◽  
Internal Standard ◽  
Ethylene Dichloride ◽  
Standard Mixture ◽  
Ethylene Dibromide ◽  
Acetone Water ◽  
Relative Standard ◽  
The Common ◽  
Hexane Solution

Abstract A method is described for the determination of the common fumigants carbon tetrachloride (CC14), ethylene dichloride (EDC), and ethylene dibromide (EDB) in grain and grain-based products. A properly prepared sample is mixed with water and hexane, an internal standard mixture of 1,2-dichloropropane (DCP) and 1,2-dibromopropane (DBP) is added, and the fumigants are codistilled with the hexane into an appropriate receiver. After the hexane solution is dried over sodium sulfate, the quantities of fumigants present are quantitated on a gas chromatograph (GC) equipped with an electron capture detector (ECD). For the matrices investigated, the relative standard deviation of the method was 6.0,9.7, and 23.1% for CC14, EDC, and EDB, respectively. Recoveries of added fumigants were 107, 95, and 101%, respectively. Comparison with an acetone-water soak extraction method gave a correlation of 0.967 between methods for EDB with odds of a difference between methods of 35%.

Rapid Thin Layer Chromatographic Determination of Aflatoxin M1 in Powdered Milk

1985 ◽  
Vol 68 (5) ◽  
pp. 952-954
Author(s):  
Maria Luisa Serralheiro ◽  
Maria Lurdes Quinta
Keyword(s):  
Aqueous Solution ◽  
Carbon Tetrachloride ◽  
Thin Layer ◽  
Limit Of Detection ◽  
Chromatographic Determination ◽  
Methanol Solution ◽  
Aflatoxin M1 ◽  
Powdered Milk ◽  
Layer Chromatography

Abstract A method has been developed for the detection of aflatoxin Mi in milk. The toxin is extracted with chloroform, the extract is evaporated, and the residue is partitioned between carbon tetrachloride and an aqueous saline-methanol solution. The toxin is once again extracted with chloroform from the methanol solution and analyzed by thin layer chromatography. The limit of detection of Mi in powdered milk is 0.5 μg/ kg; recoveries of added Mj are about 83%. The limit of detection can be improved to 0.3 μg/kg if the plate is sprayed with an aqueous solution of H2S04 after development.

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