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[en] A technique is described which enables one to obtain detailed dose characteristics of 90Sr beta-ray ophthalmic applicators. A radiochromic radiation detector which is a solid-state solution of hexahydroxyethyl pararosaniline cyanide in a nylon polymer (i.e., thin foil), has been used to determine the surface dose rate and dose distribution of these sources. The detectors are rugged, easily handled, have an equivalent response (optical density per unit absorbed dose) to photons and electrons, and produce high-resolution images. They have been found useful for this application due to the high surface dose rates [0.10-1.0 Gy (H2O)/s] and their low sensitivity (approximately 10(4) Gy for an optical density of 1.0). The foils have been evaluated on a He-Ne scanning laser densitometer with a resolution of 0.3 mum. Comparison with NIST (formerly NBS) extrapolation ionization chamber measurements indicates surface dose-rate agreement within 6%. Spectral dosimetric characteristics are presented and discussed
Journal
[en] Increased cost of lead is promoting enhanced usage of common building materials for shielding in diagnostic medical and dental facilities where only a few half-value layers (HVLs) are needed. Attenuation of primary beam X-ray photons in gypsum wallboard as a function of kVp, filtration, and wallboard thickness have been measured. Findings, obtained using a Victoreen 555 with an 0.1 DAS probe in poor geometry, are substantially in agreement with the sparse data in the literature but extend to thicker wall configurations and different kVp and filtration parameters. These findings are of value in maximizing the benefit/cost ratio for diagnostic shielding, and strengthen the conviction that, where used for shielding purposes, common building materials must be installed carefully and HVL-depth dependence considered thoroughly. (author)
Journal
Health Physics; ISSN 0017-9078; 
; v. 36(5); p. 595-600
; v. 36(5); p. 595-600
[en] RF strain female mice four months of age were used to determine LD3050 values for fission neutrons delivered at dose rates of 10 rad/min and 2 x 108 rad/min. The LD3050 was found to be independent of dose rate under the conditions of this experiment. The relative biological effectiveness (RBE) of fission neutrons with respect to gamma and X-rays was 3.83 and 3.29, respectively, when gamma and X-rays were delivered at a dose rate of 8 rad/min. (author)
[fr]
On a utilisé des souris femelles de souche RF, âgées de quatre mois, pour déterminer les valeurs de la LD3050 pour des neutrons de fission délivrés avec des débits de dose de 10 rad/min et de 2 * 108 rad/min. On a constaté que, dans les conditions de l'expérience, la valeur de la LD3050 ne dépendait pas du débit de dose. L’EBR des neutrons de fission par rapport aux rayons gamma et aux rayons X était de 3, 83 et 3,29 respectivement, lorsque les rayons gamma et les rayons X étaient délivrés avec un débit de dose de 8 rad/min. (author)[es]
Los autores utilizaron hembras de ratón de 4 meses, de la raza RF, para determinar los valores de la dosis letal LD3050 para los neutrones de fisión, con intensidades de dosis de 10 rad/min y 2 * 108 rad/min, respectivamente. Comprobaron que la LD3050 es independiente de la intensidad de dosis, en las condiciones del experimento. La eficacia biológica relativa (EBR) de los neutrones de fisión con respecto a los rayos gamma y los rayos X era 3, 83 y 3,29 respectivamente, cuando estas radiaciones se aplicaban a razón de 8 rad/min. (author)[ru]
Dlja opredelenija LD50/30 nejtronov delenija pri moshhnosti dozy 10 rad/min i 2 * 108 rad/min ispol'zovali chetyrehmesjachnyh samok myshej linii RF. Okajea los', chto LD50/30 v uslovijah dannogo jeksperimenta ne zavisit ot moshhnosti dozy. Otno sitel'naja biologicheskaja jeffektivnost' (OBJe) nejtronov delenija po sravneniju s gamma- i rentgenovymi luchami ravnjalas' sootvetstvenno 3,83 i 3,29 pri moshhnosti dozy gamma- i rentgenovyh luchej 8 rad/min. (author)Source
International Atomic Energy Agency, Vienna (Austria); 460 p; May 1964; p. 267-273; Symposium on Biological Effects of Neutron Irradiations; Upton, NY (United States); 7-11 Dec 1963; IAEA-SM--44/13; ISSN 0074-1884; ; 14 refs., 3 tabs., 1 fig.
; 14 refs., 3 tabs., 1 fig.