The concentration of several gases contained in a YAG laser induced smog was measured, and an improved gas scavenging system was tested for cleaning the smog. The YAG laser was practiced at its power of 80w for a few minutes, and the gas analysis was followed by an analogous way described in out previous paper.Judging from the figures shown in our previous two papers, the concentrations of NO_X, CO and CO_2 were not assumed so high as to be taken in account for pollution, too, by YAG laser; analysis for these gases was omitted.The concentrations of HCHO and CH_3COOH were 6 and 5 ppm, respectively, at their maximum. Those of H_2S and CH_3SH were 3 and 2 ppm, respectively, and that of CH_3NH_2 exceeded 60 ppm. The figures of HCHO, CH_3SH and CH_3NH_2 are beyond the standards for working room air : moreover, all of those observed are quite enough to be sensible as offensive smell.The experimentally tested ges scavenging system wax composed of a inlet cone, a inlet tube and a suction pump with a device of catalytically gas cleaning function. A filter inserted in the cone caught a considerably much quantity of micro-particle and tar like material. The gases to be detected in the off air from the pump were not found except trace of CH_3NH_2.
The microbial burden and dose setting for radiation sterilization of tampon for menstrual hygiene were examined, and the following results were obtained.1. The maximum and minimum contaminants per a tampon were 100 and 0,and the average was 46.1.2. The 91.2% of the 125 strains isolated from the tampon was identified as bacilli by the microbiological and biochemical activites, and Bacillus pumilus compried 35.2% of the srains. B. pumilus and B. megaterium spores indicated the highest radioresistance among those contaminants and both D- values were 0.22 Mrad.3. The difference in the D-value was not found for the radioresistance of standard strain carried on a tampon and a glass fiber filter.4. The sterilization dose (SD) was calculated to be 1.10 Mrad by the formula SD=D x log (No/N), while the SD was 0.90 and 0.76 Mrad, respectively, for the microbial burden in formations and steility tests.From above ressults, it is supposed that the sterility assurance level in 10^<-3> can be achieved by irradiating the dose less than 1 Mrad.
The degradation during storage after electron beam and γ-ray irradiation on to polymers for disposables syringes was investigated in connection with the decay curves of chemiluminescence amounts.The degradation during storage of homopolypropylene was relatively small, large part of polymers having been degraded during irradiation. The degradation during storage of copolypropylene occurred at earlier stage up to three months, while in later stage, it hardly proceeded. The degradation during atorage of electron beam irradiated samples were far smaller than that γ-ray irradiated ones. Irradiation of 2.5 Mrad with electron beam caused degradation only a little during storage. It was suggested that the degradation during storage depend on degree of oxidation during irradiation. The degradation during storage was not observed for radiation resistant polylpropylene and polymethylpentene. The degradation during storage of coprolypropylene was affected by atmosphere, being smaller in vacuo than in air.