Accumulation of enriched 235U-UO2F2 in the body had injurious effects on theimmune function of central and peripheral immune cells. After an intravenousinjection of beaU--UO,F,, the spontaneous ’H--TdR incorporation ...Accumulation of enriched 235U-UO2F2 in the body had injurious effects on theimmune function of central and peripheral immune cells. After an intravenousinjection of beaU--UO,F,, the spontaneous ’H--TdR incorporation in thymocytes andbone marrow cells decreased, with the thymocytes damaged more markedly. Theproliferation ability of spleen T and B lymphocytes were both inhibited, with Blymphocytes inhibited more severely. In spleen B lymphocytes the IL-- 1 production andIL--2 consumption were diminished. The inhibition of spleen B lymphocyteproliferation by 'U-- UOZFZ was partially restored by adding exogenous IL-- 1 or IL--2to the cultured lymphocytes obtained from 'U injected mice.展开更多
Nuclear fuel based on uranium metal alloys is utilized in research and test reactors. For the purpose of the reduction of fuel enrichment, high densities of uranium-235 in this kind of fuel are needed. This can be ach...Nuclear fuel based on uranium metal alloys is utilized in research and test reactors. For the purpose of the reduction of fuel enrichment, high densities of uranium-235 in this kind of fuel are needed. This can be achieved when uranium alloys are used containing elements such as Zr, Mo and Nb. The construction of fuel element with high-uranium density requires materials with low cross sections for neutron absorption, stability under irradiation and absence of the chemical interactions between the fuel and cladding elements. In case of U-Zr-Nb alloys, Zry (zircaloy) cladding is a better option due to the fact that they have a higher chemical compatibility when compared with the use of aluminum alloys. This study aims to develop plate type nuclear fuel using the U-2.5Zr-7.5Nb alloy dispersed in Zry. Powders of this uranium based alloy and Zry were obtained by hydriding-dehydriding process. These powders were homogenized, compacted in pellet that was sandwiched in plates and frame of Zry. This assembly was hot rolled forming the dispersion fuel miniplate.展开更多
文摘Accumulation of enriched 235U-UO2F2 in the body had injurious effects on theimmune function of central and peripheral immune cells. After an intravenousinjection of beaU--UO,F,, the spontaneous ’H--TdR incorporation in thymocytes andbone marrow cells decreased, with the thymocytes damaged more markedly. Theproliferation ability of spleen T and B lymphocytes were both inhibited, with Blymphocytes inhibited more severely. In spleen B lymphocytes the IL-- 1 production andIL--2 consumption were diminished. The inhibition of spleen B lymphocyteproliferation by 'U-- UOZFZ was partially restored by adding exogenous IL-- 1 or IL--2to the cultured lymphocytes obtained from 'U injected mice.
文摘Nuclear fuel based on uranium metal alloys is utilized in research and test reactors. For the purpose of the reduction of fuel enrichment, high densities of uranium-235 in this kind of fuel are needed. This can be achieved when uranium alloys are used containing elements such as Zr, Mo and Nb. The construction of fuel element with high-uranium density requires materials with low cross sections for neutron absorption, stability under irradiation and absence of the chemical interactions between the fuel and cladding elements. In case of U-Zr-Nb alloys, Zry (zircaloy) cladding is a better option due to the fact that they have a higher chemical compatibility when compared with the use of aluminum alloys. This study aims to develop plate type nuclear fuel using the U-2.5Zr-7.5Nb alloy dispersed in Zry. Powders of this uranium based alloy and Zry were obtained by hydriding-dehydriding process. These powders were homogenized, compacted in pellet that was sandwiched in plates and frame of Zry. This assembly was hot rolled forming the dispersion fuel miniplate.