Conjugated carbonyls with a hydroxypentanone ring produced during autoxidation of methyl γ-linolenate were examined by GC-MS. They were separated successively by gel chromatography on Sephadex LH-20 and by silicic acid chromatography. Following NaBH₄ or NaBD₄ reduction and subsequent trimethylsilylation, two types of carbonyls, as predicted, were detected. One was identified as methyl 5- [2- (2-formylvinyl) -3-hydroxy-5-oxocyclopentyl] pentanoate. Prostaglandin-like substances, that were considered as precursors of the carbonyls, were also detected.

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Interactions between humic acids and anthraquinone disperse-dyes were studied. A humic acid extracted from a marine sediment and a commercial one were used to solubilize dyes sparingly soluble in water. The solubility of dyes in humic acid solution was measured by the shake-flask method. The dye solubility in humic acid solution increases with humic acid concentration and enhancement was marked for solution of Aldrich humic acid. The addition of salts decreased the solubility of the dye but the effects were complicated. Differences in salts appeared to affect the solubility of dye little in both marine and commercial humic acids. Dye solubility increased with temperature, especially in the case of a 0.1% solution of marine humic acid at high temperature. The spectrum of the dye solubilized in humic acid solution changed and a twin peak characteristic of 1, 4-isomers of polyaminoanthraquinone disappeared and a broad peak appeared. The dye solubilized by humic acid may thus possibly exist as a solid state as a deposit on quartz. From the effects of temperature and change in the spectrum, it is suggested that interactions of the dye and humic acids may be attributable to a partition like process but structural and compositional factors of humic acid should also be considered.

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To clarify the tempering mechanism in solid-fats products, we measured solid content, average size and number of particles by the permeability method developed by us. In this study, we used margarine, shortening and standard sample before and after tempering treatment. Also, the microscopic structures of fats products were observed with a scanning electron microscope. The following results were obtained.
(1) The solid particles in the fats before tempering were agglomerates of fine particles and fine particles dispersed in a certain temperature range, resulting in rapid decrease in average size of particles and increase in solid particle number.
(2) Tempering caused marked changes in size and number of solid particles in solid-fats products, and these changes corresponded well to those of fats before tempering at certain temperature, as mentioned in (1).
(3) The dispersion of constituent fine particles in agglomerates induced by tempering was caused by the change of fat crystals to more stable polymorphism.

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Silica gels modified by alkoxyalcohols were prepared by refluxing silica gel and alkoxyalcohols in n-decane. Characterization of the modified silica gels was performed by FT-IR, DTA and elemental analysis.
Benzyl bromide, n-hexyl bromide and dibromoethane reacted with potassium acetate in the presence of the modified SiO₂ to give the corresponding acetates. Reduction of acetophenone, cyclohexanone, 1-indanone and 2-octanone with NaBH₄ proceeded smoothly in the presence of the modified SiO₂.

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An isolated surfactant phase (microemulsion, D′) appeared near a water-surfactant axis in a water/dodecyl octaethylene glycol ether/1-dodecanol system. The D′ phase formed two types of three-phase triangles with excess water, lamellar liquid crystalline and reversed micellar solution phases. The solubilization of 1-decanol in the D′ phase was rather small. The composition in the D′ phase is independent from the temperature, whereas the composition in a surfactant phase (middle phase microemulsion, D) in a hydrocarbon system was changed from water-to oil-rich regions with increase in temperature. Judging from the electrical conductivity measurement, the structures of aggregates appear to be three-dimensional continuous bilayers in the D′ phase.
A lamellar liquid crystal extended towards a water corner between the single D′ phase region and aqueous micellar solution phase region. The liquid crystals dispersed in water as vesicles in the dilute region. The correlation between the formation of the D′ phase and water-swollen lamellar liquid crystal is discussed.

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Molecular dynamic simulations were carried out for liquid-vapor interface of n-pentane. Interactions among n-pentane molecules are represented by the Lennard-Jones potential function. In this calculation, the Gibbs surface is adopted. To simulate thermodynamic quantities at a liquid-vapor interface, 216 n-pentane molecules were set in a cubic box. At first, the surface energy (U) was calculated, and then surface tension (γ). Surface energy was obtained from the difference between surface potential energy (17 replicas) and bulk potential energy (26 replicas). Surface tension was determined using the equation U=γ-T (dγ/dT).
In this calculation, the condition that γ=0 at critical temperature (470K) is introduced. From values of surface energy and surface tension, surface entropy was obtained. Surface energy was 50.80erg/cm² and surface tension, 19.13dyn/cm. Deviation in surface tention from the experimental value was ca. 19.8%. Surface entropy was 0.108erg/K cm².

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A high-performance liquid chromatographic method with high sensitivity and selectivity for analysis of anionic surfactants (ASF) is described. ASF such as alkylbenzenesulfonate (LAS), alkanesulfonate (SAS), α-olefinsulfonate (AOS), alkyl sulfate (AS) and poly (oxyethylene) alkyl ether sulfate (ES) were separated by reversed-phase chromatography using ODS-silica (Hitachi gel 3053) as a stationary phase and 1mM sodium perchlorate in acetonitrile-water (30 : 70) as a mobile phase and were detected with non-suppressor type conductive detector. The calibration curve was linear in the range from 0.005 to 17μg for C₁₂ AS-Na and the relative standard deviation with five measurements was 0.31% for 1.0μg C₁₂ AS-Na. The results of homolog analysis of LAS by the proposed method showed good agreement with those by the UV detection. Nonionic, cationic and amphoteric surfactants did not interfere with the analysis of ASF. By the proposed method, ASF in commercial household and cosmetic products were analyzed with high sensitivity and selectivity. Better separations were achieved by the gradient elution method.

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High-performance liquid chromatographic separation of diacid-1, 2-diacylglycerol isomers having different acyl groups in reversed positions as their 3, 5-dinitrobenzoates were carried out on a silver-loaded ion exchange column prepared by Christie's method using mixtures of n-hexane/1, 2-dichloroethane/ethanol as the mobile phase. Separation of diacylglycerol (DG) reversed isomers synthesized from palmitic, oleic, linoleic and linolenic acids with glycerol (1-16 : 0, 2-18 : 1-and 1-18 : 1, 2-16 : 0-DGs), (1-16 : 0, 2-18 : 2-and 1-18 : 2, 2-16 : 0-DGs), and (1-16 : 0, 2-18 : 3- and 1-18 : 3, 2-16 : 0-DGs) were achieved.

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