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191.
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193.
When the excited triplet states of disperse azo dyes with nitro groups abstract hydrogen to generate hydrazinyl (from azo groups) and nitrosyl hydroxide radicals (from nitro groups), both the radicals as H‐acceptors carry out azo scission, conversion to nitrogen dioxide via disproportionation reactions and self‐decomposition via rearrangement. A kinetic equation was formulated by the sum of these reactions, which describes the initial rates (KPA) of reductive fading. The KPA values were controlled by the rate constants of the reactions of hydrazinyl and nitrosyl hydroxide radicals as H‐acceptors, which were estimated by thermochemical analyses of the reactants, intermediates and end products using the semiempirical molecular orbital PM5 method, and by the concentrations of the reactants: H‐acceptors and H‐donors. The KPA values observed for 12 dyes were explained semi‐quantitatively by multiple routes of reactions depending upon to what extent each radical reaction was thermochemically favoured. 相似文献
194.
The microstructure development in Sb2O3-doped ZnO was studied at doping levels up to 2.0 mol%. Dopant Sb2O3 reacted with ZnO to form inclusion particles,α-Zn7Sb2O12, and inhibited the grain growth of ZnO. With increasing doping level of Sb2O3, the growth rate of ZnO decreased whereas that of inclusion particles increased. Some inclusion particles were trapped in ZnO grains at low doping levels of Sb2O3, but the volume fraction of trapped inclusion particles decreased with increasing doping level. Stereological analysis of the size and number ratios of ZnO grains and inclusion particles indicated that a compatible assumption is needed to evaluate Zener effect in two-phase sintering. 相似文献
195.
Namihira Y. Horiuchi Y. Mochizuki K. Wakabayashi H. 《Photonics Technology Letters, IEEE》1989,1(10):329-331
Highly accurate polarization mode dispersion (PMD) measurement using an interferometric detection technique with AC modulation is discussed. This technique, which searches for the interference fringe signal, was used to measure PMD in a 60 km long installed optical submarine cabled fiber 2500 m sea depth and to determine the fiber-length dependence of PMD. PMD measurement in 60-km-long installed optical submarine cabled fibers was confirmed to be less than about 0.7 ps. It was found that the fiber length dependence of the PMD measurement in the less than ~20-km-long cascaded uncabled fibers was proportional to √L ; however, the PMD data in the long-length (over ~50 km long) fibers were slightly scattered 相似文献
196.
This paper describes principles, analyses and experimental studies of a brushless and self-excited single-phase synchronous generator which was devised by one of the authors. The analyses and test results of performances of the generator system of which the armature winding is supplied with an exciting power from a transformer which is connected with the generator armature winding through a reactor or a condenser are presented. It can be found from the test results that the necessary exciting power is less in case of the armature winding supplied with DC exciting current from the transformer through the condenser. 相似文献
197.
Shiang Suo Huang Lan Hui Chih Chia Hsien Lin Long Y. Chiang Tadahiko Mashino Masataka Mochizuki Kensuke Okuda Takasi Hirota Ming-Cheng Tsai Ming Cheng Tsai 《Fullerenes, Nanotubes and Carbon Nanostructures》2001,9(3):375-395
The effects of hexasulfobutylated (FC4S), the fullerene derivative on the contraction of smooth muscle were tested pharmacologically on the circular muscle of stomach of guinea pigs. The effects of monomalonic acid C60 (MMA C60) on the same preparations were compared. The effects of those compounds on the taenia coli, portal vein and vas deferens of guinea pigs were also tested. The FC4S did, while MMA C60 did not elicit contracture of the circular muscle of stomach and taenia coli. Both FC4S and MMA C60 did not elicit contraction on the portal vein and on the vas deferens of the guinea pig. Prazosin (0.5 μM) or propranolol (0.5 μM) did not alter the FC4S elicit contracture of the circular muscle of stomach. However, atropine (0.01, 0.1 and 1 μM), tetrodotoxin (0.1 μM) or low calcium medium decreased reversibly the FC4S elicited contracture of the circular muscle of stomach. The effect of FC4S on the contracture of the gastric muscles was also tested using various muscarinic receptor subtype antagonists. 4-DAMP (1 μM), muscarinic M3 receptor antagonist, and tropicamide (1 μM), muscarinic M4 receptor antagonist, did not alter the contracture elicited by FC4S. Pirenzepine (0.1 μM), muscarinic M1 receptor antagonist, and methoctramine (0.25 μM), muscarinic M2 receptor antagonist, significantly decreased the FC4S elicited contracture of the circular muscle. Atropine (1 μM) or tetrodotoxin (0.1 μM) completely blocked the FC4S elicited contracture of the circular muscle of stomach. It is concluded that FC4S elicited contracture of the circular muscle of stomach. The effect may be due to FC4S acts on the cholinergic cells existed in the gastric muscle and indirectly activating the tetrodotoxin dependent releasing of the transmitters from the cells, then, activating the muscarinice M1, M2 receptors in the muscle eliciting the contractures. 相似文献
198.
Toshiko Mizokuro Hiroyuki Mochizuki Nobutaka Tanigaki Takashi Hiraga 《Thin solid films》2008,516(9):2411-2415
We report selective doping of vapor of yellow dye, ferrocenedimethanol into exposed (UV-irradiated) areas of novolac resin films. When vapor of the dye was contacted with micro-patterned resin films containing both exposed and unexposed areas, the dye was doped only into the exposed areas, resulting in fabrication of micro-pattern containing the dye. On the contrary, ferrocene and other ferrocene derivatives were doped both exposed and unexposed areas of the resin. A contact angle measurement of aqueous drops on each dye indicated that the chemical affinity between hydroxyl groups of ferrocenedimethanol and exposed areas of the novolac resin will enhance selective doping of the dye into the exposed areas. 相似文献
199.
Hiroyuki Mishima Mituo Kakei Toshio Yasui Saori Miyamoto Yasuo Miake Takaaki Yanagisawa 《Frontiers of Materials Science in China》2008,2(2):179-181
The present study was aimed at examining the nature of apatite crystal in the tooth apparatus of a conodont fossil using transmission
electron microscopy (TEM), scanning electron microscopy (SEM), laser Raman microprobe spectrometry and electron-probe microanalysis
(EPMA). The hard tissue of the condont consisted of 2 layers and the organization varied with the size of the crystal. Higher
magnification showed that the crystals were observed in the lattice of (100) and the central dark lines were not present.
Ca, P, and F were detected in the crystal using EPMA. Our results indicate that the apatite crystal in conodont fossils is
not hydroxyapatite but fluorapatite. 相似文献
200.