The labile d₂₀₀ of the C form, d₀₂₀ of the B form, and d₁₀₀ of the A form for stearic and lauric acids by the changes in temperature were measured from -40°C to near their melting points by the X-ray powder diffraction method. Plots of the side spacing against the temperature showed distinct discontinuities corresponding to the existence of the second order transitions in long chain fatty acids rather than the polymorphic transition. These discontinuities in the coefficients of thermal expansion were observed at the following temperatures : stearic acid-C form, 30°C ; B form, 20°C and lauric acid-C form, 15°C ; A form, 8°C. The coefficients of expansion above the discontinuous points were equal to 1.5 to 2.7 times as great as those below.

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A technique of high-performance liquid chromatography (HPLC) was applied to the analysis of triglycerides of soybean oil. The triglycerides were clearly separated into six peaks by HPLC on a column packed with, μ-Bondapack C₁₈ using methanol-chloroform mixture as a solvent. From the fatty acid compositions of the triglycerides of these six peaks, it was found that the separation of triglycerides by HPLC under the conditions used was governed by the degree of their unsaturation in addition to carbon number ; that is, the higher the degree of unsaturation of the triglyceride, the earlier the elution. From the results obtained, the possible triglyceride compositions of soybean oil were estimated.
As a result, it was suggested that the use of HPLC in combination with GLC and TLC can provide more detailed information concerning triglyceride structure.

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The phase behavior of lithium soap/hydrocarbon oil and lithium soap/synthetic oil greases has been investigated using DTA. The change in the shape and size of soap micelle in the grease was examined with an electron microscope. It has been found that the phase behavior and the shape and size of the soap micelles in the grease are greatly affected by the oxidation stability of the base oil used. For the lithium stearate/squalane grease, the phase transition temperature and the L/D value of the fibers formed by the soap micelles decreased with the oxidation time. However those of the grease prepared with pentaerythritol tetraoctanoate which was stable for oxidation were hardly affected. These facts may be rcduced to a small amount of the polar compounds produced by the oxidation of a base oil.

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With a total of 10 kinds of synthesized 1-monoglycerides, seven of even-numbered monoglycerides of C₁₀ to C₂₂ (Carbon numbers of fatty acid) and odd-numbered monoglycerides of C₁₅ C₁₇ and C₁₉, examinations were made on the presence of Sub- α₂, and their correlation to modification numbers, transition temperature, enthalpy and entropy by difference in length of the molecular chain and even-odd number of carbons.
1) Sub- α₂ was observed not only in C₁₈, C₂₀ and C₂₂, but also in C₁₉, but not in those below C₁₇. Comparison of the IR spectrum of Sub- α₂ with that of Sub- α₁ showed that they are quite similar with the exception of a slight difference in the OH absorption band. Transition from Sub- α₂ to Sub- α₁ is reversible. 2) Transition temperature (below 310 K, 37°C) of monoglycerides with a short chain of below C₁₅ showed a difference from the values reported in literature when in metastable state (α, Sub α₁). Regarding its correlation to the number of carbons, transition temperature of α→ fusion and α → fusion increased β → regulary with increase in the number of carbons, and there was no alternation between even and odd number of carbons. However, such alternation was seen in the transition of Sub- α₁ to α and of Sub- α₂ to to Sub- α₁, and this phenomenon was entirely reverse of that in triglycerides.
3) With respect to the correlation of enthalpy and entropy to the number of carbons, enthalpy and entropy of α → fusion and Sub- α₁→α of manoglycerides with above C₁₇ chain showed the same tendency as the transition temperature. Alternation appeared in the case of β→ fusion, differing from the transition temperature. This may be due to the difference in the optically active L and DL compounds of monoglycerides. In the transition of Sub-α to α in monoglycerides of less than C₁₆, transition enthalpy increased in inverse proportion to the decrease in the number of carbons. This may be due to the occurrence of a competitive action between the fatty acid group and glycerol group at the time of transition, resulting in the increasing action of the glycerol group with shortening of the molecular chain and in a metastable state. The enthalpy and entropy per methylene group were R/2 and Rln 3, respectively, agreeing well with theoretical values.

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Synthesis and surface activities of the N^ε -acyl-L-lysine and their derivatives were investigated. The N^ε -acyl-L-Lys were selectively obtained from fatty acid salts of Lys by the thermal dehydration. This method is superior in selectivity and convenience to the usual methods for the selective acylation of the ε-amino group in Lys, because the usual methods need to protect the α-amino group against the acylation and also to use special acylating agents such as acyl chloride or p-nitrophenyl ester of fatty acid.
The N^ε lauroyl-L-Lys was less soluble into water in spite of its amphoteric structure, and ethylene oxide (EO) was added to increase the solubility.
Wetting power, foaming power, emulsifying powe rand detergency of EO adducts of N^ε -lauroyl-L-Lys were measured. Wetting power varied with pH like usual amphoteric surfactants, but the variation decreased with increasing of the number of EO.

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The tests for acute toxicity to fish were carried out on nine commercial surfactants of various chemical structures including secondary alcohol derivatives.
The tests were extended to study the toxicity of biodegradation intermediates of some surfactants in river water. It was found that the TLm (48 h) values of alcohol ethoxylates and nonylphenol ethoxylates after 4 days biodegradation in river water were 91 mg/l and 3.7 mg/l, respectively, based on the initial concentration.
The tests were also extended to see the relationship between changes in surface tension and changes in toxicity. In the case of alcohol ethoxylates, surface tension of 48 dyn/cm after 4 days biodegradation was found to be high enough for fish to be alive, while in the case of nonylphenol ethoxylates, 51 dyn/cm was found to be too low for fish to be alive.

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An ultraviolet absorption spectroscopic method has been used generally for the determination of ferulate content in rice bran oil. However, the analytical accurate results are not obtainable, because of the presence of some substances interfering the above method. Moreover, another method using both TLC and ultraviolet spectroscopy takes a long time for the analysis.
In this work, the quantitative estimation of ferulates in rice bran oil by high performance liquid chromatography (HPLC) was investigated. It was found that operating conditions shown in Table-2, were optimum for the separation of ferulate from other components in rice bran oil. The peak of separated ferulate in the chromatogram was measured, and the calibration curve of the relation between the weight of ferulate and peak area was used to calculate the f erulate content. In this case, β-sitosteryl ferulate was used as the external standard sample.
Since the interfering substances for the ultraviolet spectroscopy were removed and the ferulates were separated by HPLC the results acquired by the method mentioned above are more accurate as compared with that were determined directly by ultraviolet spectroscopy. In addition, the analytical procedure takes less than 15 minutes in almost cases. It is apparent that the time needed for the analysis per one sample by HPLC is shorter than that by the method using both TLC and ultraviolet spectroscopy.

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