[en] The presence of a satellite peak on the wavelength axis was shown in the spectral distribution of scattered laser light due to electrons in high pressure arcs. The method of direct electron density measurement only from its location in the wavelength axis was thus contrived. Its features are as follows. (1) There is no need of obtaining the absolute intensity of scattered light. (2) The satellite peak being sharp, only this limited portion needs to be oserved, no need for the overall spectral distribution. (3) The satellite peak is over several nm away from the central laser wavelength, so the stray light in the vicinity presents no problem. The detection apparatus is simple in configuration, being of optical fiber, PMT, coaxial cable and synchroscope. (Mori, K.)

[en] Gamma-radiolosis of D-glucose in aqueous solution under anaerobic condition was investigated. D-glucose was significantly decomposed by action of a hydroxyl radical, a primary radiolytic product of water. Under anaerobic condition, glucose radicals formed by hydrogen abstraction of hydroxyl radical were dehydrated to give deoxygenated sugars, and a part of the radicals followed disproportionation reaction to afford dicarbonyl sugars. Among the products formed through these reactions, 2-deoxy-D-arabinohexono-1, 4-lactone (G in N₂=0.6, G in N₂O=0.8), 3-deoxy-D-erythrohexosulose and other 3-deoxy sugars as deoxygenated compounds, and D-arabinohexosulose and D-xylohexos-5-ulose as dicarbonyl compounds were identified. From these results, the radiolytic scheme of D-glucose in the absence of oxygen was proposed. (auth.)

[en] Gamma-radiolysis of fructose in aqueous solution under aerated conditions formed various oxidized products, such as dicarbonyl hexoses, lower molecular aldoses and aldonic acids. Among these radiolytic products, D-arabinohexosulose (1, G = 2.2) and D-threo-2,5-hexodiulose (2, G = 1.5) were identified as major hexose derivatives, and D-threo-2,3-hexodiulose (3) and D-lyxo-hexos-5-ulose (4) as minor products. The radiolytic processes were found to be derived through fructose radicals, similarly to anaerobic radiolysis of fructose. The mechanism of radiolysis was proposed to be initiated by hydrogen abstraction with hydroxyl radical, followed by formation and degradation of fructose hydroperoxy radicals. (author)

[en] The measurement of the decrease of electron density in the positive column of an arc remaining between electrodes after the arc has finally extinguished is considered as a measure for deciding the limit of breaking capacity in power breakers. However, it is no exaggeration to say that this measuring technique is not yet developed. In the thermal plasma in a region of several thousand degrees of gas temperature at 1 atm or more, electron collision frequency reaches tens of GHz, therefore, if microwaves having an equivalent frequency is irradiated, its change of absorption coefficient becomes gentle around the cut-off electron density, thus clear cut-off phenomena are lost. In this paper, it is clarified that the inner electron density was able to be measured only by the attenuation of irradiated microwave transmission through plasma, utilizing this adverse effect in an opposed sense. The fact that the particle composition and the electron collision frequency are uniquely definite as the functions of temperature in a thermal plasma at several thousand degrees and 1 atm permits the above measurement. In the paper, the method is shown to calculate the electron density corresponding to the thickness of high temperature air layer taken as a parameter for substantial cut-off and complete transmission. This permits intuitive judgement whether transmitted microwaves exceed or are below the two electron density levels depending on frequency and thickness only by simply transmitting microwaves through high temperature air layer. Microwaves used are 70 GHz and 20 GHz. (Wakatsuki, Y.)

[en] The inductive energy storage system (IES system) has been developed for the energy source of a fusion reactor. This paper presents the characteristics of circuit breaker units which will be used for the IES system. A small scale parallel breaking test circuit, in which two vacuum circuit breaker units are used, was constructed. The power source for the circuit was a condenser bank of 730 microfarad. The relation between arc voltage and arc current, and current wave forms in both vacuum valves operated in parallel were observed. Simulation calculation for the small scale circuit was performed. The obtained wave forms were similar to the measured forms. It was found that the current through both breakers was nearly balanced when the difference of breaking time of both breakers was small. Simulation calculation method for large scale parallel breakers was developed. Use of a series inductance of 100 microhenry will save the difference of breaking time. (Kato, T.)

[en] Irradiated D-fructose solution exhibited marked enhancement in browning reaction with amino acid, and this effect depended on some radiolytic products of fructose. The radiolytic products formed in solution under aerated and anaerobic conditions were fractionated by column chromatography on Sephadex G-10, LH-20 and ion-exchange resin and by TLC on silica gel. The browning activity of each fraction was determined by reaction with glycine. The browning active products in the fraction were identified by GLC, GC-MS and TLC; they were: 6-deoxy-D-threo-2,5-hexodiulose, D-threo-2,5-hexodiulose, D-arabino-hexosulose and 4-deoxy-L-glycero-2,5-hexodiulose from irradiated solution under anaerobic conditions and D-threo-2,5-hexodiulose and D-arabinohexosulose from solution under aerated conditions. The browning reactions of the model compounds with glycine also indicated that D-threo-2,5-hexodiulose and 6-deoxy-D-threo-2,5-hexodiulose were more active than D-arabinohexosulose and 3-deoxy-D-erythrohexosulose. (author)

No abstract available

No abstract available