Strahlenchemische Veränderungen an Polyvinylchlorid bei Einwirkung von Kobalt-60-Gammastrahlung
The role of air oxygen in the radiochemical changes of polyvinyl chloride was investigated. A polyvinyl chloride emulsion polymeride with a K value of 60 to 65 was used as a sample. It was radiated in the form of powder, films, and massive cylinders in high vacuum and in air. The total viscosity of the powders undergoes, after irradiation in vacuum, a slight deterioration at doses up to 5 x 10/sup 6/ r but at higher doses a lattice-like polymerization occurs. In irradiation in air the color of the sample does not vary, but in vacuum a brown color occurs. The behavior of massive cylinders is quite different from that of powders after irradiation. There is no variation in the total viscosity after irradiation in air and vacuum. Decomposition was observed up to doses of 5 x 10/sup 5/ r, then an increasing lattice-life polymerization and insolubility occurred. A red color is observed after doses of 3 x 10/sup 5/ r and it deepens with increasing irradiation doses. Film irradiated in air was not colored, but coloration occurred in vacuum irradiation. (J.S.R.)
Änderung einiger Eigenschaften des Polyvinylchlorids durch ionisierende Strahlung
Various polyvinyl chlorides were exposed to x and gamma radiation from 1O/sup 2/ io 1O/sup 6/ r in air. One series of samples was irradiated in vacuum. The viscosity of dissolved samples, the dieleciric properties, and the breakdown voltage of the irradiated polymers were determined. (J. S. R.)
Simulating the Illuminance and Efficiency of the LEDs Used in General Household Lighting
Abstract The advantage of the LEDs illumination in general household lighting was proposed. High efficiency white LED as the light source was provided the energy saving illumination of the general household lightings. Different spaces in general household with different standards of average illuminance were designed and simulated by LightTools and DIALux software. The power consumptions and efficiency of traditional illuminated light sources and LED light source in lighting the household environment were analyzed and compared with each other at the same standard of average illuminance. Finally, it provided the advantage of using white LEDs in different spaces of the general household lighting.