Electric properties of mixed anionic-nonionic surfactant systems in aqueous solutions above the cmc have been studied in term of pNa values, electrical conductivities, and dielectric constants; these systems were sodium 3, 6, 9-trioxaicosanoate (ECL) -hexadecyl poly (oxyethylene) ethers (POEn, n=10, 20, 30, and 40). The degree of ionic dissociation of mixed micelle decreases with increasing the number of oxyethylene groups in the nonionic surfactant. The electrical conductivity decreases with increasing the number of oxyethylene groups in the nonionic surfactant, in spite of the decrease of activation energy for conduction. The sizes of mixed micelles also decrease. This may be attributed to the fact that an ideally mixed micelle is easier to form for a nonionic surfactant including shorter poly (oxyethylene) chains than for that including longer poly (oxyethylene) chains.

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Using the seed of two kind of soybeans, peanut, sunflower, corn and Brassica chinensis var. Komatsuna, comparative examinations were made for changes in the content and composition of tocopherols in lipid of their seeds during the initial stage of growth from germinating to just before expanding cotyledons.
1) Total tocopherol content in lipid component of soybeans decreased rapidly at early germination, and after a following temporary increase tended to decrease gradually. That of peanut, sunflower and corn tended to increase gradually after a rapid decrease at early germination. However, that of Komatsuna tended to increase gradually during germination without a rapid decrease at early period.
2) As to tocopherol composition, in general, the percentage of α-tocopherol tended to increase during germination while that of γ-and δ-tocopherol tended to decrease, this tendency being parti-cularly prominent in Komatsuna.
3) Fatty acid composition changed little during germination in all seeds examined. Total sterol content in lipid component of seed tended to increase gradually during germination, but its composition did not change so clearly as that of tocopherols, except the percentage of brassicasterol decreased gradually in Komatsuna.

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It was reported in a previous paper that a small amount of hydroperoxide (2×10^-2μeq) could be determined by potentiometry with excellent accuracy and reliability.
In the present work, the electric potential of a sample prepared for potentiometric determination of peroxide value (POV) is shown to be proportional to a logarithmic amount of hydroperoxide in a sample solution, which enables us to measure POV directly from its potential without titration.
Indeed, the calibration curve obtained for determination of hydroperoxide showed good lineality (correlation coefficient γ=0.998) from 0.25 to 10μeq of peroxide and POV determined by this calibration curve method agreed fairly well with those by potentiometric titration demonstrating the usefulness of this method.
As it is not necessary to titrate with sodium thiosulfate, this method enables the rapid determination of a small quantity of hydroperoxide appearing in a small amount of natural triglycerides, phospholipids, and also of natural lipids extracted from biological materials and food products. Especially this method is advantageous for the analysis of lipid extracts because the sample solution, which is obtained by Bligh and Dyer or Folch method, is directly subjected to this procedure without evaporation.

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The rolling-up mechanism on the removal of oily soil mixture of liquid paraffin (Nujol) and oleic acid from polyester (PET) substrate in aqueous surfactant solutions was studied by measuring the contact angle and the interfacial tension. Surfactants used were nonylphenyl poly (oxyethylene) ether (EO : 11) (NP-11) and sodium dodecylsulfate (SDS).
In the NP-11 solution, Nujol alone placed on PET as a droplet, the contact angle of which was about 110°, was not rolled up, however, Nujol mixed with oleic acid was removed easily from PET by rolling-up. The addition of 5% oleic acid into Nujol resulted in the most efficient removal.
As for the effect of surfactants on the interfacial tension at Nujol containing 5% oleic acid/water interface, the NP-11 lowered the interfacial tension markedly almost to 0dyn/cm, while the SDS lowered only to about 3dyn/cm. Furthermore, the equilibrium contact angle of Nujol with 5% oleic acid on PET increased in NP-11 solution and decreased in SDS solution as compared with those of Nujol alone.
The calculated residual works of detergency (W_{R, v}) in the system of Nujol with 5% oleic acid on PET were 0.09dyn/cm in 5×10^-3% NP-11 solution and 3.3dyn/cm in 5×10-1% SDS solution, respectively. Therefore, in both NP-11 and SDS systems, W_{R, v} decreased in the presence of 5% oleic acid in Nujol.
From these results, it is concluded that the addition of small amount of oleic acid into Nujol is effective for increasing the equilibrium contact angle and especially for lowering the oil/water inter-facial tension to facilitate the removal of Nujol by rolling-up.

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N- (2-Hydroxyethyl) alkanamides were prepared by the reaction of methyl esters of fatty acids (C⁸-C¹⁴) with 2-aminoethanol and the corresponding sodium sulfates were obtained according to the usual method.
Using the aqueous solutions of those salts, surface tension, critical micelle concentration, Krafft point, wettability, foaming power, solubilizing power, lime dispersing power, and emulsifying power were determined and compared to each other in connection with the carbon numbers of starting fatty acids.
Thus, judging from the general features of properties, the surfactant derived from methyl laurate was recognized to be superior to others.

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The synergistic antioxidant effect of tocopherol (Toc) and citric, malic or succinic acid in lard and palm oil was investigated. The acids were dissolved homogeneously in a commercial distilled monoglyceride and then added to the fats.
1) The monoglyceride manufactured from cotton seed oil was selected as the medium because of lower melting point and higher dissolubility for citric acid than that manufactured from beef tallow.
2) The monoglyceride showed a little antioxidant effect in the lard.
3) The antioxidant effect of Toc in the lard was little affected by the addition of citric acid. It seemed that few pro-oxidant metals such as iron, copper, etc, were contained in the fat. Also no synergistic effect of the acid was observed in the palm oil. These results suggested that current oils and fats with the progress of oil-refining technique contained a smaller amounts of metal compounds than previous oils and fats.
4) Malic and succinic acids in the lard did not show the synergistic effect with Toc and neither did citric acid.
5) In the case of lard containing 4.4 ppm of iron, the addition of citric acid to the substrate remarkably improved the antioxidant effect of Toc. The results lead to the conclusion that the effect is indicated on the basis of the function of citric acid as metal deactivator.

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Alkylation of mesityl oxide (7) with 1-chloro-3-methyl-2-butene (1) using potassium or sodium hydroxide in an aprotic solvent afforded a mixture of isopentenyl mesityl oxide, (4), (5) and (9) in 83% yield, which were hydrolytically decomposed to 6-methyl-5-hepten-2-one (3) in 95% yield in an autoclave.

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Six chelate-resins of which main-chains were composed of the polyesters from ethylenediamine tetraacetic acid (EDTA) and 2, 2-bis [4- (2, 3-epoxypropyloxy) phenyl] propane were prepared. The main-chain was cross-linked by EDTA dianhydride or by diethylenetriaminepentaacetic acid (DTPA) dianhydride in three different molar-ratios. The chelate-resins obtained were designated E-resins, and D-resins, respectively.
These chelate-resins prepared had the remarkable pH-dependence on the adsorptivity of metal ions. A copper ion was adsorbed on E-and D-resins up to 0.55mmol/g even at pH 1, whereas Ca²⁺, Mg²⁺, Mn²⁺ and Cr³⁺ were negligibly adsorbed under the same condition. The maximal Cu²⁺-adsorption capacities of both E- and D-resins were found at around pH 4. The Cu²⁺-adsorption capacities increased with an increase of the copper concentration up to at 0.06M and kept constant to be 1.4mmol/g at the copper concentration above 0.06M. The amount, 1.4mmol/g, corresponds to about 80% of the theoretical value which is calculated by assuming that all chelating ligands of EDTA-and DTPA moiety in the resin form the (1 : 1) chelate with the metal ion.

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