Back-scattering absorber materials for gamma-rays
Abstract
Abstract Back-scattering absorber materials for gamma -rays comprising a mixture consisting of 70 to 90 percent by weight of lead compound, 10 to 20 percent by weight of barium compound and 3 to 10 percent by weight of iron compound, and a vehicle. In one type of embodiment, polyvinyl alcohol in 25 percent aqueous solution of 28 to 39 percent by weight of said mixture is used as the vehicle. In another type of embodiment, the vehicle is a mixture comprising 30 parts of vinyl acetate as a film-forming agent, 0.2 part of methyl cellulose dissolved in 10 parts of water as a thickening agent, and 4 parts of ammonium salt of vinyl acetate copolymers in 25 percent solution as a dispersing and wetting agent, and said vehicle mixture being 25 to 67 percent by weight of the first principal mixture. Regardless of the type of vehicle, the back-scattering absorption characteristics of the absorber materials are substantially invariant, so far as the composition of the first said principal mixture is kept constant.
Inventors
- 👤 Masao Kato
- 👤 Goro Tanaka
- 👤 Seigoro Yamamoto
Bibliographic Details
Claims Analysis
Total Claims: 4References Cited (Backward Citations)
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