Increase of photographic sensitivity by the latent image intensification (latensification) technique was studied at β-radiation autoradiography. Well-known post-exposure latensification, gold latensification, gold hypersensitization and prolonged development treatments were used, and new simultaneous red-light exposure treatment was also examined according to the latent image formation theory. Each single treatment increased the sensitivity a little. Combination of the treatments, especially with the prolonged development was effective. Large increase of sensitivity was obtained with a combination of the simultaneous red-light exposure and the prolonged development, although some fog appeared. The dispersion of latent image specks was intense at the β-radiation, and so many small and undevelopable silver specks were formed. They could not get the developability with the single treatment, but could do with the combination. The simultaneous red-light exposure would reorganize those specks to large and developable specks.
Experimental adsorption isotherms for H2O and D2O on dehydrated cobalt complex [Co (en) 3] Cl3at 10, 25 and 35°C, showing equilibrium vapor pressure plateaus, could be closely approximated by an error functional dinomial expression proposed here. Relationships of its parameters with temperature were examined, and temperature-dependent characteristic equations common to H2O and D2O were then obtained. The isotope effect is recognized in the differences between H2O and D2O in their coefficients. Therefore, the adsorption isotherms for both waters on the cobalt complex can be estimated at various temperatures around 10-35°C. The examined complex has the satisfactory capacity of adsorption for water compared with popular adsorbents. Its unique water adsorption characteristics would be applicable to techniques for treatment of tritiated water vapor.
99mTc-GSA scintigraphy was performed to evaluate reserved hepatic function in 32 patients with hepatobiliary tumor. Each parameters; HH15, LHL15 and T1/2 showed good correlation with ICG15 in patients without obstructive jaundice. Contrary, each indices did not significantly correlate with ICG15 in cases including obstructive jaundice. Each indices obtained from99mTc-GSA scintigraphy was useful parameters to reflect liver functional reserve which was not affected by hyperbilirubinemia. New index, T1/2 was more useful than other indices for differentiating hepatic dysfunctional state from normal condition.
We constructed an automatic operation system of air-conditioners and ventilators in a radiation controlled area to minimize electric consumption. The system operates the airconditioner and the ventilator of each ventilation unit when someone is staying in rooms belonging to the unit based on information from an access control system to the controlled area and lighting switches in front of individual room. For understanding of operation conditions and confirmation of radioactive concentration in air lower than the legal limit at the ventilation stack, we also constructed an automatic ventilation monitoring and recording system, which makes complete operation records of each ventilator automatically. These systems enabled to achieve sharp energy-saving compatible with radiation protection.
Dose distribution in the oral region of a subject treated by radiation therapy for cancer of the epipharynx was determined retrospectively by ESR measurements of 38 tooth enamel samples using a calibration curve prepared previously. The result is considered to agree well with the prescribed doses. Doses to ten of the above samples were determined by the additive re-irradiation method as well as the calibration curve method. Both methods yielded almost identical dose values in the range of 3 to 20Gy.