A first-order transition between the liquid-expanded and the liquid-condensed phases in insoluble monolayers of fatty acid esters as detected by measurement of equilibrium spreading pressure

Kinetics of the title reactions has been studied, using nickel(II) 2,4-pentanedionate/triethylaluminium system as a model catalyst. Initial rate measurements showed that in both cases the hydrogenation is first order in hydrogen, zero order in the octadecanoate and a fractional order (close to one) in the catalyst. Both hydrogenations have similar activation energies (30.2 ± 2.3 kJ mol-1 and 28.9 ± 2.6 kJ mol-1 for the (Z)- and (E)-9-octadecenoate, respectively). Based on these data and the results of competition experiments, two models have been proposed to describe isomerization of the octadecenoates (either direct or via an intermediate).

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Hydrogenation of Fatty Acid Esters. III. Hydrogenation of Methyl (9Z,12Z)-Octadecadienoate and Methyl (9Z,12Z,15Z)-Octadecatrienoate

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19922593 ◽

1992 ◽

Vol 57 (12) ◽

pp. 2593-2604 ◽

Cited By ~ 1

Author(s):

Jana Krupičková ◽

Jaroslav Včelák ◽

Jiří Hetflejš

Keyword(s):

Fatty Acid ◽

Rate Constants ◽

Initial Rate ◽

Product Distribution ◽

Fatty Acid Esters ◽

Product Analysis ◽

First Order ◽

Time Changes ◽

Acid Esters

The title hydrogenation catalyzed by nickel(II) 2,4-pentanedionate-triethylaluminium system has been studied with the use of combination of initial rate measurements with time changes of product distribution. It was found that the hydrogenation of methyl (9Z,12Z)-octadecadienoate is first order in the octadecadienoate. Similar results were obtained also for (9Z,12Z,15Z)-octadecatrienoate. The course of both reactions has been described by models involving set of parallel and consecutive hydrogenation steps and reversible isomerizations. Computed rate constants for hydrogenation of methyl (9Z,12Z)-octadecadienoate support qualitative conclusions deduced from the product analysis.

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Development of the determination methods of fatty acid esters of chloropropanediols in fat-rich foods

Chinese Journal of Chromatography ◽

10.3724/sp.j.1123.2012.09002 ◽

2014 ◽

Vol 31 (2) ◽

pp. 95-101

Author(s):

Xiaobo YAN ◽

Shaoming WU ◽

Nan LI ◽

Huadong LV ◽

Wusheng FU

Keyword(s):

Fatty Acid ◽

Fatty Acid Esters ◽

Determination Methods ◽

Acid Esters

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Mesomorphic Behaviour of Saturated and Monounsaturated C18 and C22 Fatty Acid Esters of Cholesterol

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19940833 ◽

1994 ◽

Vol 59 (4) ◽

pp. 833-840

Author(s):

Slavomír Pirkl

Keyword(s):

Phase Transitions ◽

Fatty Acid ◽

Fatty Acid Esters ◽

Aliphatic Esters ◽

Acid Esters

The phase transitions and effective optical rotary power of saturated and monounsaturated aliphatic esters of cholesterol with 18 and 22 carbon atoms in the chain have been described. The effect of cis/trans isomerism on these properties is discussed.

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First-order transition features of the triangular Ising model with nearest- and next-nearest-neighbor antiferromagnetic interactions

Physica A Statistical Mechanics and its Applications ◽

10.1016/j.physa.2007.04.051 ◽

2007 ◽

Vol 383 (2) ◽

pp. 351-371 ◽

Cited By ~ 14

Author(s):

A. Malakis ◽

N.G. Fytas ◽

P. Kalozoumis

Keyword(s):

Ising Model ◽

Nearest Neighbor ◽

Order Transition ◽

First Order ◽

First Order Transition

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The occurrence of long chain polyprenols in leaves of plants of Rosaceae family and their isolation by time-extended liquid chromatography

Biochemistry and Cell Biology ◽

10.1139/o92-068 ◽

1992 ◽

Vol 70 (6) ◽

pp. 448-454 ◽

Cited By ~ 9

Author(s):

Ewa Świeżewska ◽

T. Chojnacki ◽

W. J. Jankowski ◽

K. Singh ◽

J. Olsson

Keyword(s):

Liquid Chromatography ◽

Fatty Acid ◽

Large Scale ◽

Fatty Acid Esters ◽

Large Scale Preparation ◽

Scale Preparation ◽

Wet Weight ◽

Rosaceae Family ◽

Acid Esters ◽

Long Chain

The long chain polyprenols composed of 30 and more isoprene units from leaves of plants belonging to the genera Potentilla and Rosa have been described. They occur in the form of fatty acid esters. The composition of polyprenol mixture was species dependent and its content reached ca. 0.5% wet weight. Large scale preparation of individual polyprenols from a natural polyprenol mixture was performed using time-extended liquid chromatography on the hydrophobic gel Lipidex-5000.Key words: long chain polyprenols, Rosaceae.

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Separation of Fatty Acid Dimethyl Esters on an Ionic Liquid Gas Chromatographic Column

Journal of Chromatographic Science ◽

10.1093/chromsci/bmaa097 ◽

2020 ◽

Author(s):

R E Pauls ◽

B Pease

Keyword(s):

Ionic Liquid ◽

Fatty Acid ◽

Stationary Phases ◽

Carbon Number ◽

Fatty Acid Esters ◽

Reaction Products ◽

Isomer Separation ◽

Metathesis Reaction ◽

Polydimethyl Siloxane ◽

Acid Esters

Abstract An ionic liquid (IL) 111 column was compared with other commonly employed stationary phases including polydimethyl siloxane and polyethylene glycol for the separation of fatty acid monomethyl and dimethyl esters. The fatty acid esters employed in this study were derived from metathesis reactions of vegetable oils both with and without olefins. The IL 111 column demonstrated enhanced performance compared with conventional columns for the separation of these esters. These advantages included significantly enhanced retention of dimethyl esters relative to monomethyl esters, excellent cis/trans isomer separation and the ability to analyze higher carbon number dimethyl esters. As a result, these columns are highly suited for the analysis of mixtures of mono- and dimethyl fatty acid esters found in lipid metathesis reaction products or to determine monofunctional impurities in samples of commercial dimethyl esters.

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