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71.
A comparison of monoacetyldiglycerides obtained from authentic phosphatidylcholines by acetolysis with those obtained by phospholipase C-acetylation was made to examine the intermolecular acyl migration, the intramolecular acyl migration between C-1 and C-2, and the formation of 1,3-isomer in the acetolysis reaction. Egg yolk phosphatidylcholine also was used. It was revealed that is acetolysis, the intermolecular acyl migration and selective degradation of polyunsaturated fatty acids did not take place at all. The intramolecular acyl migration, including the formation of 1,3-isomer, occurred to a small extent. Appreciable difference was not found in comparison of molecular species compositions of monoacetyldiglycerides derived by both methods from egg yolk phosphatidylcholine, except small differences found in the contents of two kinds of molecular species. 相似文献
72.
Curing catalyst for epoxy resins was newly found. The catalyst consists of aluminum complex and silanol. Lack of one component of the pair does not cure epoxy resins. The epoxy resins cured with the catalyst are characterized by excellent electrical properties, especially at high temperature, due to the absence of strong acid species in the cured epoxy resin matrix. Heat-resistant property of the resin was also excellent. These properties were compared with those of epoxy resin cured with commonly used BF3 complex. 相似文献
73.
The NMR spectra of olefinic protons in the four representative conjugated fatty acid methyl esters, methylcis-9,trans-11-octadecadienoate, methyltrans-9,trans-11-octadecadienoate, methyl α eleostearate, and methyl β eleostearate, were studied. The chemical shift of each olefinic
proton in these compounds was determined by considering their intramolecular environment. Coupling constants were also obtained
as the results of spectral analysis. 相似文献
74.
R. Usuki T. Suzuki Y. Endo T. Kaneda 《Journal of the American Oil Chemists' Society》1984,61(4):785-788
The quantities of chlorophyll (CHL) A and B, and pheophytin (PHY) A and B in 10 kinds of refined edible oils were estimated
by the fluorometric method. The results revealed that CHL and PHY were present in commercial edible oils. PHY A showed the
highest content at ca. 67% in total pigments. Compositional ratios of CHL and PHY were similar in different kinds of plant
oils. Through the analysis of rapessed oils at every refining step, we determined that PHY is not formed during oil refining.
In the autoxidation of soybean oils to which various amounts of CHL mixtures had been added, the peroxide value of tested
oils increased in proportion to the total chlorophyll content. In addition, the compositional changes of the 4 components
during autoxidation were investigated. 相似文献
75.
76.
Takatoshi Tsujimura Junichi Fukawa Kiyoshi Endoh Yuuji Suzuki Kazuhiko Hirabayashi Takahiro Mori 《Journal of the Society for Information Display》2014,22(8):412-418
To come out with a successful organic light‐emitting diode (OLED) lighting business, it is very important to have clear differentiation of OLED from LEDs. Flexible OLED has merits, such as capability to be mounted on the curved wall, which is not easy for LEDs to achieve the feature. There are several approaches to make flexible OLEDs especially among those plastic barrier films that can bring high level of flexibility, which could not be achieved by any conventional lighting method. In this paper, barrier films with various water vapor transmission rate values, including 10? 6 order, are applied, and the conditions to have almost no dark spot growth under 85 °C and 85% high temperature/humidity test are shown. Flexible OLED panels are manufactured with the world's first roll‐to‐roll equipment using plastic barrier film. 相似文献
77.
Junzo Suzuki 《应用聚合物科学杂志》1976,20(1):93-103
Polyethylene glycol (molecular weight 8000) was degraded by ozone in 1% aqueous solution of pH 12. Chemical oxygen demand of the solution decreased with increasing ozone consumed. Intrinsic viscosity of the solution lowered exponentially as a result of the ozonization. The number of breaks calculated from the viscosity indicated that two molecules of ozone were consumed for one cleavage of the polymer chain. The molecular weight distribution obtained by gel permeation chromatography was very broadened and molecular weight was lower as well, and the polymer chain was found to be cleaved randomly by ozone. The production of formic ester, ethylene glycol, diethylene glycol, triethylene glycol, and hydrogen peroxide was confirmed by IR, NMR, gas chromatography, and chemical analysis. These observations could be accounted for by electrophilic attack of ozone on the ether bond. 相似文献
78.
Combustion, Explosion, and Shock Waves - Zero-dimensional computations of nanosecond-order ignition using a nanosecond discharge are performed with two constraints. The effects of these constraints... 相似文献
79.
In order to elucidate the electrochemical properties of iron rust, galvanostatic cathodic polarization of rusted steel and rust electrodes, prepared by fixing a piece of rust plate on an acrylic plate with conductive adhesive, was examined. The change in the amount of crystalline substances in the rust layer was observed by X-ray diffraction. The electrochemically active intermediate substances, could not be identified by X-ray diffraction, but their behaviour was distinguished from that of crystalline substances. The rest potential of the rust electrode was controlled by the equilibrium potential of intermediate substances. “An overlapping dual electrode” model is proposed for rusted steel in aqueous solution. Beneficial elements added to weathering steel inhibit the formation of crystalline magnetite in the cathodic reduction process of rust and increase the electrical resistance of the rust layer. 相似文献
80.
The extended X-ray absorption fine structure (EXAFS) method and transmission electron microscopy (TEM) have been used for characterizing the local structure and morphology of ferric oxyhydroxides, α-FeOOH and γ-FeOOH, with and without chromium. These ferric oxyhydroxide powders were prepared from aqueous solutions containing iron and chromium ions. Radial structural functions for iron obtained by Fe K edge EXAFS spectra showed that the linkage of structural units formed by FeO6 octahedra in γ-FeOOH is distorted by chromium addition, while such distortion in α-FeOOH is not clearly detected. On the other hand, Cr K edge EXAFS spectra showed that the local structure around chromium does not necessarily correspond to the local structure around of iron, which is observed by Fe K edge EXAFS spectra. This suggests that the structural units containing iron and chromium are heterogeneously distributed in these ferric oxyhydroxides. The local structural information was discussed coupled with morphological features of these ferric oxyhydroxides observed by TEM. 相似文献