• Bulletin of the Korean Chemical Society
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• 제32권6호
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• pp.1965-1969
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• 2011

1,2,4,5-tetraoxane, mono and dinitrate glycerol carbonate ester derivatives of stearic acid were synthesized along with the known 9(10)-keto methyl sterate, methoxy mono-nitrate and dinitrate of methyl stearate. Their cetane numbers (CNs) were investigated to evaluate their viability for use as CN improvers. The CN performances of tetraoxane and all of the nitrate derivatives were investigated at 500 and 1000 ppm concentrations and compared to that of a traditional CN improver 2-ethylhexyl nitrate (2-EHN). The experimental results suggest that all derivatives evaluated in this study showed better CN improvement than base diesel fuel. Specifically, the 1,2,4,5-tetraoxane derivative of stearic methyl ester was superior to all derivatives studied, also being superior to 2-EHN. We also discussed the correlations between the observed CN trends and thermo-analytical data resulted from thermo gravimetric analysis curves (TGA) and differential scanning calorimetry (DSC).

• Bulletin of the Korean Chemical Society
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• 제7권2호
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• pp.120-124
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• 1986

In order to investigate effective solar energy conversion system, the light-induced electron transfer reactions have been examined across single-lamellar liposomes incorporated organic photosensitizers such as anthracene and naphthalene derivatives. We have observed photosensitized reduction of methyl viologen (1,1'-dimethyl-4,4'-$bipyridinium^{2+}$) dissolved in the exterior aqueous phase of the pigmented phospholipid liposomes when EDTA, as electron donor, is dissolved in the enclosed aqueous phase of the liposomes. The anthroyl stearic acid incorporated in the hydrophobic bilayer of liposomes leads to much less quantum yield for the photosensitized reduction of $MV^{2+}$ than the anthracene carboxylate incorporated in the outer hydrophilic layer. However, ${\beta}$-carotene with anthroyl stearic acid incorporated into the bilayer enhances the quantum yield significantly (${\Phi}{\simeq}0.2-0.3$), preventing the reverse reaction of electron transfer ($MV^+_\ {\rightarrow}MV^{2+}$) so that it might be useful for solar energy conversion into chemical energy. A naphthalene derivative, octadecyl naphthylamine sulfonic acid incorporated into the outer layer of liposomes results in less efficiency of $MV^{2+}$ reduction than anthroyl stearic acid. These results have been also tested with respect to lipid components of liposomes.

• 한국작물학회지
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• 제47권
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• pp.140-149
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• 2002

Sesame (Sesamum indicum L.) is probably the most ancient oilseed crop known in the world. Sesame seed is known for its high nutritional value and for having oil (51%) and protein (20%) content. The fatty acid composition of sesame oil is palmitic acid (7.8%), stearic acid (3.6%), oleic acid (45.3%), and linoleic acid (37.7%). Sesame oil is characterized by a very high oxidative stability compared with other vegetable oils. Two lignan-type compounds, sesamin and sesamolin, are the major constituents of sesame oil unsaponifiables. Sesamol (a sesamolin derivative) can be present in sesame seeds and oils in very small amount. Other lignans and sesamol are also present in sesame seeds and oils in very small amount as aglycones. Lipid oxidation activity was significantly lower in the sesamolin-fed rats, which suggests that sesamolin and its metabolites contribute to the antioxidative properties of sesame seeds and oil and support that sesame lignans reduce susceptibility to oxidative stress. Sesaminols strongly inhibit lipid peroxidation related to their ability to scavenge free radical. The sesame seed lignan act synergistically with vitamin I in rats fed a low $\alpha$-tocopherol diet and cause a marked increase in a u-tocopherol concentration in the blood and tissue of rats fed an $\alpha$-tocopherol containing diet with sesame seed or its lignan. The authors are reviewed and discussed for present status and prospects of quality evaluation and researched in sesame seeds to provide and refers the condensed informations on their quality.

• KIEE International Transactions on Electrophysics and Applications
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• 제11C권3호
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• pp.49-52
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• 2001

The derivatives of spironaphthooxazine gause photoisomerization when they are illuminate with UV light. We investigated the photoisomerization of spironaphthooxazine derivatives for holographic memory. Langmuir-Blodgett (LB) films contain amphiphile spironaphthooxazine derivatives which can be applied in molecular devices by a change of molecular level energy and a refractive index. In order to investigate the photoisomerization of spironaphthooxazine derivatives at the air/water energy and a refractive index. In order to investigate the photoisomerization of spironaphthooxazine derivatives at the air/water interfaces, spironaphthooxazine derivatives with side alkyl chains were synthesized. The films of the spironaphthooxazine derivatives were characterized by the measurement of UV/vis spectroscopy, Brewster Angle Microscopy (BAM) and Atomic Force Microscopy (AFM). The monolayers of the spironaphthooxazine derivatives mixed with stearic acid were stable at the air/water interface and visualized by the measurement of BAM. The spironaphthooxazine derivative monolayers on the glass surface showed the maximum efficiency of diffraction as 0.99% by the measurement of holography.