植物油を原料に用いた輸送用代替燃料製造法として固体触媒存在下におけるトリンのオゾンによる分解を行ったところ，トリンが完全に分解し，約10％の炭化水素（C9～C17）およびラクトン等の含酸素化合物の混合物が得られた。この反応は，触媒の種類や反応条件によって分解物の生成量やその分布が大きく異なることがわかった。

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植物油を用いた輸送用代替燃料製造法として固体触媒存在下におけるトリンのオゾン分解を行ったところ、トリンが完全分解し約10％の炭化水素（C9からC17）およびラクトン等の含酸素化合物が得られた。この反応において、触媒の種類やオゾン分解反応条件によって分解物の生成量やその分布が大きく異なることがわかった。また、オゾン分解反応経路についても検討を行った。

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【目的】加熱中の食材内部の熱移動を遅延現象を考慮した指数式で表せることを既報¹⁾で明らかにしているが、食材中の成分は加熱により固体脂の融解、たん白質の熱凝固、でん粉の糊化、ゲル・ゾル転移などの相変化が生じるため、熱移動を単純に定式化し得ない場合が考えられる。そこで、加熱下で相変化がみられる上記成分を含むモデル系を対象に、一次元方向の加熱中の内部温度を追跡し、相変化近傍点での遅延時間定数(τ_ｘ)を算出し、熱移動に及ぼす種々の要因を検討した。
【方法】試料はトリン（固体脂）、寒天ゲル、ゼラチンゲル、でん粉懸濁液とした。それらを加熱用金属容器で、試料底部を105℃に加熱し、一次元方向の内部温度の経時変化を測定した。さらにトリン、寒天、ゼラチン試料に小麦でん粉を5_から_60%添加したモデル系を調製し、加熱中の相変化点の観察と遅延時間定数(τ_ｘ)を算出、比較した。
【結果】トリンは油脂の融解による相転移が見られ、急激な温度低下が観察された。この試料に小麦でん粉を添加していくと徐々に温度曲線は滑らかになり、60%添加でほぼ相転移点はみられなくなった。寒天・ゼラチン系でも同様の現象が見られ、ゲル・ゾル転移による温度降下が、小麦でんぷん量が増すにつれ消失した。これらの食材の相変化点近傍での遅延時間定数(τ_ｘ)にはモデル系により違いが見られ、いずれも相変化による吸熱現象が影響すると推測された。しかし、上記でん粉のみの系においては糊化現象の影響が温度上昇曲線には観察されなかった。でん粉を添加することで相転移が消失していく機構については今後の検討課題である。1) K.Nagao et al., J.Home Econ. Jpn, 52, 241(2001)

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Benzene solution of tristearin at various temperatures segregates tristearin in single crystals, needle-like crystals or in amorphous state depending on circumstances. The crystals are examined under polarizing and electron microscopes for their shape and microstructure, and they are found. to be of R-form with long spacing of 45Å and short spacing of 4.61Å from their X-ray diffraction patterns. The solution at 20°C gives single crystals of plate form when the concentration is low, but crystals of needle form when the concentration is high. At especially low concentrations, the grown single crystals have screw dislocations in steps of 40Å high. The crystals that grew in needles have also steps which are however 300Å_??_450Å in height suggesting that there are 8-10 molecular layers in every one of these steps.

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The phase transition of the polymorphic forms in the binary system, tristearin-tripalmitin, has been studied by X-ray diffraction.
(1) The lowest melting form α was obtained by melting and chilling the mixtures, and the next form β' and β was obtained by transition form α-form. All three forms in this binary system formed solid solutions of which long spacings varied with composition of the system.
(2) Using the continuously variable specimen-temperature devise, it was observed that α-form in this system transformed into subα-form at -50°C or so and that this phase trasition was reversible.
(3) Using the same devise, X-ray diffraction pattern of β' and β-forms at elevated temperature was obtained up to its melting point. It was observed that the specific lattice spacing in β' and β-forms changed at elevated temperatures and authors called β' and β at near its melting point as β'* andβ* respectively. This β'* and β*-forms transformed reversibly into β' and β near at room temperature.
(4) Using the same devise, it was observed the α-form transformed into β* in the pure glyceride by heating. In the solid solution, it was concluded that α-form transformed into β'* (or β'), deformed β*, and β* successively. It was suggested that the deformed β* might be imperfectly β* in which the specific crystal face of β* yet developed. It would be concluded that the intermediate pattern named by Hoerr was attributed to mixture of β'* and deformed β*.
(5) The value of side spacings of each polymorphic form is summarized as follows :
(1) β 4.58, 3.85, 3.69Å (room temp.)
β* 4.58, 3.85, 3.75Å (near its mp)
It is observed that the last lattice spacing often changed a little in the solid solutions.
(2) deformed β* 4.58, broad 3.8 Å (near its mp)
(2) β' 4.19, 3.80Å (room temp.)
β'* 4.19, 3.85Å (near its mp)
(4) α 4.14 Å (room temp.)
sub α 4.12, broad 3.7 Å (below -50°C)

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We investigated difference of lubricity of triolein, tristearin and rapeseed oil as a reference under high temperature conditions for acceleration of oxidation degradation. Though the triolein consisting of the monounsaturated fatty acid showed superior oxidation durability and oiliness to the rapeseed oil including the polyunsaturated fatty acid, phenomena which might be caused by corrosion and elimination of adsorbed film were observed on both lubricants. On the other hand, there was a possibility that the tristearin consisting of the saturated fatty acid has a superior forming capability of adsorbed film and not be related to corrosion.

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Pure glyceryl tristearate was prepared as solid fat particles by complete hydrogenation of olive oil, and pure glyceryl trioleate was prepared as liquid oil by solvent fractionation of olive oil.
The rheological properties of mixtures of these two components were investigated in comparsion with their microstructure revealed by X-ray diffraction. The flow curves of various mixtures were measured by a Weissenberg rheogoniometer and the temperature dependence of viscoelasticity was studied by an forced oscillation apparatus. Two kinds of specimen were prepared. One is a suspension body, that is, simple mixture of triolein and tristearin which is uniformly mixed by stirring it with a glass rod at room temperature, and the other is a molten body, that is, the mixture of tristearin and triolein which is molten at 90°C and recrystallized at 0°C. In each mixture the fraction of tristearin is from 5 to 45% by weight.
All the flow curves for mixtures of 5 to 25% tristearin were typically non-Newtonian. From the relation between the apparent viscosity η and the rate of shear γ, the shear rate dependence of viscocity -(d logη/d log γ) was calculated at a high rate of shear 20sec.^-1 and at a low rate of shear 1 sec.^-1. From the relation between the fraction of tristearin and -(d log η/d log γ), it was observed that the shear rate dependence of viscosity was much larger for the suspension body and at a lower rate of shear. These results suggest that a firm texture is developed in the specimen after the melting of suspension due to the formation of network structure of crystallites of tristearin.
The temperature dependence of dynamic elastic modulus E^* and loss factor tan δ has been measured for mixtures of 25 to 45% tristearin. It has been found that the mixtures of 25 to 40% tristearin show entropy elasticity, that is, the elastic modulus increases with the rise of temperature and that on the other hand, a 45% tristearin mixture shows energy elasticity, that is the elastic modulus decreases with the rise of temperature. It is reasonably assumed that a network structure having crosslinked molecular chains such as exists in rubber in the present mixtures. A number of small crystallites of tristearin would produce the crosslinking points. The molecular weight between crosslinks was tentatively calculated from the elastic modulus at room temperature using Kuhn's theoretical equation for rubber elasticity and found to be in the same order with the molecular weight of tristearin and triolein.
The variation of E^* and tan δ was followed during the heating and cooling at a fixed rate for the same samples. Heat treatment profoundly alters the physical properties of mixtures. After a cycle of heating and cooling, E^* at room temperature increases and tan δ decreases. Observation by X-ray diffraction shows that the degree of crystallinity increases slightly after the heat treatment and also that the habit of crystals changes from β type to β' type. It is seen, however, that log E^* increases almost linearly with the degree of crystallinity for both β and β' types, and that these two lines are almost parallel in the range of crystallinity investigated less than 40%. The value of tan δ is largest at the fraction of tristearin 30 to 35 percent where the rubber-like property is observed most obviously.
The results for the present mixtures where the melting temperatures of two components are far apart would give some useful knowledge to consider the physical properties of more complicate mixures of oils and fats. The network structure formed by the small crystallites and the mobile molecules between them crosslinked by these crystallites would give an interesting model for ellucidating the mechanical properties of ordinary fats.

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Strain behavior of nylon 6 fiber and tristearin as a soil model compound under high hydrostatic pressure up to 250 MPa was studied with a piezometer at 25°C. It was obtained that the initial compressibility, κ ₀, was 1.8 × 10^-4 MPa^-1 for nylon 6, and 3.0 × 10^-4 MPa^-1 for tristearin. Furthermore, a calculation of compressibility in the amorphous region of nylon 6 was tried. These results suggested that putting the fiber under high hydrostatic pressure was effective for washing. This was supported from a microscopic observation. The experimental results were discussed in terms of the initial compressibility and the density.

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The releasing rate of poly(3-hydroxybutyrate)-P(3HB)-microapheres containing Lastet, an anticancer agent, was investigated both in vitro and in vivo. The rate of the release of Lastet from P(3HB) microspheres was very small and only 20% was released during a 15-day period. The addition of acylglycerols to P(3HB) increased the releasing rate of Lastet. P(3HB) microspheres which contained 25% glycerol tristearate (GTS) and 25% glycerol monostearate (MTS) released 100% and 50% of the Lastet during a 10-day period, respectively. In the surface of P (3HB) microspheres without acylglycerol, a number of small holes of 1 μm diameter were observed. And large holes of 5 μm diameter were observed in the surface of P(3HB) microspheres with GTS. There was no significant difference in surface property between P(3HB) microspheres with MTS and those without acylglycerol. P (3HB) microspheres which contained 25% MTS and 10% Lastet were administered intraperitoneally to rats and the change of Lastet concentration in blood and tissue was investigated. Although in low levels, Lastet was detected in the blood up to 24hr after administration. And Lastet was detected in high levels in the mediastinal tissue up to day 7. The change of the surface property of microspheres confirmed by scanning electron micrographs suggested that the decomposition of P(3HB) in vivo may be accelerated by some enzyme to increase the release of drugs.

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