Results 241 to 250 of about 2,596,520 (293)

Introduction to pyrolysis–capillary gas chromatography

Journal of Chromatography A, 1999
By breaking large molecules into characteristic smaller fragments, analytical pyrolysis extends the use of gas chromatography to the analysis of polymeric materials, including natural polymers such as cellulose as well as synthetics. An understanding of the chemistry involved permits interpretation of the information present in these molecular ...
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Stochastic Model of Gas Capillary Chromatography

Communications in Statistics - Simulation and Computation, 2012
The delayed passage of a gas through a narrow cylindrical tube is considered on the basis of delayed reflection of a diffusion process from boundaries of a segment. The Laplace image of the delayed first exit time from the tube of a given length is derived.
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Capillary gas chromatography of carbolines

Journal of Chromatography A, 1982
Abstract A method was developed for the gas chromatographic analysis of carbolines (pyridoindoles) on fused-silica glass capillary columns, coated with SuperoxTM-4. Separation characteristics are presented for all four possible isomers of carboline and several methyl-, methoxy- and dihydro-derivatives fo β-carboline (norharman).
M.E. Snook, O.T. Chortyk
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Capillary gas chromatography of lupin alkaloids

Journal of Chromatography A, 1983
The resolution and identification of twelve lupin alkaloids are demonstrated using capillary gas chromatography and gas chromatography-mass spectrometry. The quantitative capabilities of capillary gas chromatography are illustrated by specific reference to the four major alkaloids of lupinus angustifolius, namely lupanine, 13-hydroxylupanine ...
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Ammonia as carrier gas in capillary gas–liquid chromatography

Journal of Chromatography A, 2001
Influence of helium and ammonia as carrier gases on retention of neutral solutes on polyethylene glycol has been studied theoretically and experimentally. It was shown that the influence of ammonia on the retention varied significantly depending on the solute's nature.
V G, Berezkin, V R, Alishoev, A A, Korolev, I V, Malyukova   +3 more
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Pulse circulation gas chromatography on capillary columns

Talanta, 1987
The method and equipment for pulse circulation high-resolution gas chromatography on glass capillary columns have been developed. The separation of a mixture of C(6)H(6), C(6)H(5)D, C(6)H(3)D(3) and C(6) D(6) on carbonized columns coated with squalane has been taken as an example to show the advantages of the method.
V P, Chizhkov, S S, Pavlov, N V, Sterkhov, V M, Ravikovich, E F, Litvin, E A, Varyvonchik   +5 more
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Wetting Phenomena in Gas Chromatography Capillary Columns

Nature, 1962
IN some instances poor efficiency with capillary columns has been reported, especially when glass capillaries were used. This may be due to two quite different phenomena : bad liquid-phase distribution on the smooth wall of the capillary caused by non-uniformity of radius, or non-wetting properties of the stationary phase.
F, FARRE-RIUS, J, HENNIKER, G, GUIOCHON
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Capillary gas-solid chromatography

Russian Chemical Reviews, 1996
The current state of gas adsorption chromatography on open tubular capillary columns is analysed. The history of the development of this method and its role in gas chromatography are considered. The preparation of open tubular adsorption capillary columns, fundamentals of the theory of retention and of broadening of chromatographic zones, and the use ...
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Identification of polysaccharides in pharmaceuticals by capillary gas chromatography

Journal of Pharmaceutical and Biomedical Analysis, 1989
A sensitive method for the identification of polysaccharides in pharmaceuticals is described. Polysaccharides are isolated by gel filtration and subsequently hydrolysed. The monomeric carbohydrates obtained are transformed into oxime-trimethylsilyl derivatives and analysed by capillary gas chromatography.
G, Vanlaeke, H, Cuppens, L, Leyssens, J, Raus   +3 more
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Determination of Urinary Succinylacetone by Capillary Gas Chromatography

Journal of Chromatographic Science, 1984
The average analytical recovery of succinylacetone added to urine and separated by capillary gas chromatography was 69% for solvent extraction and 72% for anion exchange separation. Treating succinylacetone with hydroxylamine hydrochloride at a pH of less than 5 caused formation of a derivative separated by capillary gas chromatography into two isomers:
M, Tuchman, C B, Whitley, M L, Ramnaraine, L D, Bowers, K D, Fregien, W, Krivit   +5 more
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