Examination was made of the preparation and properties of new types of water-based cutting fluids additives derived from various materials. Attention was directed to synthetic additives classified according to their functional groups : carboxylic acids, esters, dibasic acids, ethers, amides, substituted fatty acids and others. Methods for examining water-soluble cutting fluids additives for laboratory and practical use are described in detail.

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The denaturation of bovine serum albumin (BSA) by mixed surfactant systems was studied by examining surfactant adsorption on BSA. Polyoxyethylenealkylether (alcohol ethoxylate : AE) inhibited SDS-binding to BSA with consequent denaturation of BSA. The higher the concentration of AE or the larger the adduct number of oxyethylene (EO), the greater was the inhibitory effect of AE on SDS-induced denaturation of BSA. The adsorption of AE on an electrostatic surface significantly increased when SDS was present. The enthalpy of adsorption of the SDS-AE mixed system on BSA as determined with a microcalorimeter clearly differed from that of pure SDS or AE. The AE effect on SDS-induced BSA denaturation is thus due to the adsorption of AE on the alkyl chain of SDS electrostatically bound to BSA. The adsorption of AE apparently stabilizes the alkyl chain of SDS electrostatically bound to BSA, with a consequent decrease in the binding of SDS to BSA.

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Molecular interactions between L-α-dipalmitoylphosphatidylcholine (DPPC) and steroids differing in the number of double bonds in a monolayer and bilayer were examined by measurement of surface pressure, permeability and microviscosity. The steroids used were 7-dehydrocholesterol (7-DHC), cholesterol (Chol) and β-cholestanol (β-Chol) along with Vitamin D₃ (VD₃) having an opened steroid B-ring. The limiting molecular area for the steroids in the DPPC-steroid mixed monolayer increased with the number of double bonds in the steroid ring in the order β-Chol<Chol<7-DHC. Liposomes were formed with steroids at steroid mole fractions less than 0.5 and VD₃ less than 0.3. The permeability of the liposomes containing steroids decreased with the number of double bonds in the steroid ring and steroid limiting molecular area. That of liposomes containing VD₃ with limiting molecular area exceeding that of steroids was higher than for liposomes containing steroids. The effects of steroids or VD₃ on the permeability of Liposomal bilayer membranes cannot be adequately explained based on the number of double bonds or limiting molecular area, although Demel et al. have shown a correlation between the effects of sterols on the permeability of liposomes and molecular area of sterols in monolayers. The permeability of liposomal bilayer membranes containing steroids or VD₃ was found in this study straightly decrease with microviscosity near the bilayer center. The permeability of liposomal bilayer membranes may thus be considered to related to microviscosity near the bilayer center, which can be evaluated based on fluorescence polarization determined with the fluorescent probe, 12AS.

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The flotation of Hg²⁺ ions using chitosan derivative (chitopearl) as an adsorbent, polyacrylamide (PAA) as a coagulant and hexadecyltrimethyl-ammonium chloride (HTAC) as a frother was carried out. The floatability exceeded 98% at pH 410, and showing a maximum of nearly 100% was obtaind for 2.03×10^-7 mol dm^-3 Hg²⁺ ion solution by bubbling nitrogen gas with the addition of 1000ppm chitosan derivative, 10ppm PAA and 10ppm of HTAC. Hg²⁺ ions may possibly form a strong coordination bonds with amine groups of chitosan derivative. A tentative structure of the sublate is proposed to explain the action of the adsorbent, coagulant, and frother to promote the flotation of Hg²⁺ ions.

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In this study, amphiphiles possessing two equivalent ammonium groups substituted with one methyl and two dodecyls, and a connecting chain were synthesized; the connecting chain consisting of such hydrophilic group that hydroxyl group and ether linkage were introduced on and into the alkanediyl chain. This paper reports the structural effects of a segment connecting two quaternary ammonium salts on the recognition of amino acids in the hydrolysis of amino acid esters using bis-quaternary ammonium salts as catalysts. The hydrophilic nature of the connecting chain was found to have effect on substrate recognition. A connecting chain with high HLB (Hydrophile-Lipophile Balance) increased the hydrolyzing rate of a hydrophilic substrate but decreased that of a hydrophobic substrate. From the relationship between the rate constant k₂ and Michaelis constant K_m in the hydrolysis of amino acid esters, clearly shows that the uptake process of substrate is a rate-determining step, that is, a substrate is recognized by connecting chain in the uptake step. The connecting chain may thus be considered to form a pocket capable of discerning the hydrophilic nature of a substrate.

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Phytosterol is used medically for reducing total blood cholesterol (T-Ch). This study was conducted to examine the capacity of diacylglycerol containing phytosterol for reducing T-Ch. Following the administration of 10g diacylglycerol containing 400mg phytosterol over a 4-week period, significant reductions in T-Ch (3.4%) and low density lipoprotein (6.5%) were observed. The availability was 67%. This is the lowest dose of phytosterol ever reported. This result suggests that the coexsiting diacylglycerol might affect the reduction of T-Ch by phytosterol.

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For quantitative and metabolic examination of sitosterol in plants, deuterio-labeled sitosterol and related steroids were synthesized from stigmasterol. The base-catalyzed enolization of a 3, 6-diketone group and reduction of the diketone with lithium aluminum deuteride were conducted as key reactions for the introduction of deuterium atoms into the steroidal A/B-ring. [2, 2, 3, 4, 4, 6, 7, 7-²H₈] Sitosterol was obtained at 89% isotopic purity. The present labeling method for introducing eight deuterium atoms would appear, based on the present results, to be applicable to other sterols. Possible biosynthetic intermediate steroids from sitosterol to sitostanol were also prepared in deuterio-labeled form.

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Five organophosphorus pesticides (dichlorvos, parathion-methyl, malathion, chlorpyrifos and chlorfenvinphos) were added to crude soybean oil and the oil was refinined by degumming, alkali-refining, bleaching and deodorization. The amount of the organophosphorus pesticides in the oil were determined immediately after each process. The results are as follows :
(1) By degumming treatment, each of organophosphorus pesticides in crude oil decreased slightly.
(2) By alkali treatment, dichlorvos in the degummed oil decreased obviously, though other organophosphorus pesticides remained about 80% or more.
(3) By bleaching treatment with the absorbent, the decreased rate of dichlorvos and chlorfenvinphos was about 70% and 60%, respectively, while the decreased rate of malathion and chlorpyrifos was 30% and 5%, respectively. Parathion-methyl reduced remarkably with absorbent containing activated carbon.
(4) Each of organophosphorus pesticides were completely removed by the deodorization processing at 260°C.
(5) It was confirmed that the organophosphorus pesticides (dichlorvos, parathion-methyl, malathion, chlorpyrifos and chlorfenvinphos) in crude soybean oil were completely removed by usual refining treatment.

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The thermal oxidation rate of frying oils were determined based on in specific gravity (SG), which was found to increase linearly with heating time. The heat oxidation rate constant k_SG and heat deterioration rate constant k_RI of various frying oils were determined by simultaneous measurements of specific gravity (ΔSG) and refractive index (ΔRI). Even when heat oxidation rates of the oils were the same, the deterioration rates would differ in some cases and thought the latter were the same thermal oxidation rates would differ. Thermal oxidation and deterioration are thus differ and must be considered separately. Heat oxidation rate constants k_SG ware calculated based on following heat oxidation law of frying oils. dSG/dθ=k_SG (S/W) ·P/1013, ΔSG=k_SG (S/W) ·θ·P/1013, where k_SG (g, cm^-2, h^-1), SG : specific gravity (25/25°C or 40/25°C), S/W : specific surface (g/cm²), θ : heating time (h), P : atmospheric pressure (hPa), k_SG of the frying oils examined were in the range of 3×10^-4 to 24×10^-4.
If the point at which a frying oil is no longer suitable for frying use is 2527% polar material content, then reacted oxygen are calculated to bring increase of specific gravity 45×10^-450×10^-4 at ΔV/ΔW=0.

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