ISSN:0193-2691    

DOI:10.1080/01932699408943573

出版商:Taylor & Francis Group    

年代:1994

数据来源: Taylor

摘要:

Phase equilibria in systems alkanoic acid-alkylamine-water have been determined at 298.2 K. In the system hexanoic acid (A) - hexylamine (B) only one isotropic solution phase is formed. This solution phase is in eqilibrium with almost pure water. The strong A1B1complex shows catanionic surfactant properties as concluded from phase equilibria studies in the system A1B1-heptane-water. This system behaves like ordinary microemulsions. The dominant feature of the phase diagram with ethanoic acid -dodecylamine is the large D phase. In addition there exist a large solution phase, a hexagonal phase and a small cubic I phase.

ISSN:0193-2691    

DOI:10.1080/01932699408943574

出版商:Taylor & Francis Group    

年代:1994

数据来源: Taylor

摘要:

The subject of the present investigations is a ternary system (lecithin - D2O - PAE16). The methods of the small angle X-ray diffraction and NMR were used. In the region of the water swilling lamellar structure an intermediate phase as well as a room temperature hexagonal phase at low water concentrations were observed.

ISSN:0193-2691    

DOI:10.1080/01932699408943575

出版商:Taylor & Francis Group    

年代:1994

数据来源: Taylor

摘要:

In this paper a new class of multichain non-ionic surfactants based on lysine with two octyl, decyl, dodecyl or tetradecyl chains and one polydispersed polyoxyethylene diethanolamide head group are introduced. Measurements at air/water interface and bulk solution of surface-active properties such as surface tension and critical micelle concentration were made. These compounds were obtained by condensation of the corresponding long chain Nα, Nxdiacyl lysine with a polydispersed oxyethylene diethanolamine which was prepared in our laboratory. A preliminary study of their water solubility properties is also described. The surface-active properties were evaluated by measuring the variation of surface tension and the formation of a presumable CMC as a function of concentration in the aqueous solution. All compounds were soluble in water up to 0.5% (w/v). They showed normal surface tension values in water solution and presented higher CMC than classical polyoxyethylene alcohols non ionic surfactants with the same number of carbon atoms in the hydrophobic moiety. In this series when each chain is increased by four methylene units, the CMC falls to about one-hundreth of its previous value.

ISSN:0193-2691    

DOI:10.1080/01932699408943576

出版商:Taylor & Francis Group    

年代:1994

数据来源: Taylor

摘要:

Handling and storage of polyunsaturated lipids is a difficult problem due to oxidation. Oxidation products cause reduction in sensoric quality and can also have negative physiological effects, all of which obstruct the use of otherwise nutritionally important compounds. Therefore it is important to find techniques to prevent this quality deterioration. It is shown in this work that the oxidation of a fish oil can be decreased if the oil is transformed into a microemulsion with ascorbic acid and α-tocopherol used as antioxidants. Tocopherol will be localized in the hydrocarbon chain region whereas ascorbic acid is accumulated in the polar parts of the microemulsion.

ISSN:0193-2691    

DOI:10.1080/01932699408943577

出版商:Taylor & Francis Group    

年代:1994

数据来源: Taylor

摘要:

NMR spectra were recorded of the silicon species obtained in the reaction between tetraethoxysilane and calcium nitrate hydrate in ethanol.

ISSN:0193-2691    

DOI:10.1080/01932699408943578

出版商:Taylor & Francis Group    

年代:1994

数据来源: Taylor

ISSN:0193-2691    

DOI:10.1080/01932699408943579

出版商:Taylor & Francis Group    

年代:1994

数据来源: Taylor