The Experts below are selected from a list of 4485 Experts worldwide ranked by ideXlab platform
Hiroshi Sekimoto - One of the best experts on this subject based on the ideXlab platform.
-
Radiotoxicity hazard of inert matrix fuels after burning minor actinides in light water reactors
Progress in Nuclear Energy, 2001Co-Authors: Afroza Shelley, Hiroshi Akie, Hideki Takano, Hiroshi SekimotoAbstract:Abstract Ingestion Radiotoxicity hazard index of inert matrix spent fuels are investigated after burning minor actinide (MA) isotopes in LWRs and compared with the hazard index of MOX and MA burning MOX (MOX+MA) spent fuels. As U-free fuels, ROX: (PuO 2 +ZrO 2 ) and TOX: (PuO 2 +ThO 2 ), are considered, in which MA's are added as oxides. The Radiotoxicity hazard index of ROX+MA spent fuel is less than that of TOX+MA and MOX+MA spent fuels due to the lower density of actinides in spent fuel. Some of cooling years the toxic yield of ROX+MA spent fuel is even less than that of MOX spent fuel, if the initial loaded MA in ROX is about 0.5 at %.
-
Radiotoxicity hazard of u free puo2 zro2 and puo2 tho2 spent fuels in lwr
Progress in Nuclear Energy, 2000Co-Authors: Afroza Shelley, Hiroshi Akie, Hideki Takano, Hiroshi SekimotoAbstract:Abstract The Radiotoxicity hazard of U-free Rock-like oxide: ROX (PuO 2 +ZrO 2 ) and Thorium oxide: TOX (PuO 2 +ThO 2 ) LWR spent fuels is investigated and Radiotoxicity hazard of MOX spent fuel is considered as a reference case. The long-term ingestion Radiotoxicity hazard of ROX spent fuel is one third and nearly one fourth of that of TOX and MOX spent fuels, respectively. This is because the discharged Pu and long lived Np in ROX fuel is less than that of TOX and MOX fuels. In TOX fuel, discharged Pu and MA are lower than that of MOX fuel but the long-term Radiotoxicity hazard of spent fuel is nearly the same as MOX spent fuel. At the cooling 10 5 years, the Radiotoxicity hazard of TOX spent fuel is approximately ten and three times higher than that of ROX and MOX spent fuels, respectively due to higher toxic contribution of 229 Th in TOX spent fuel.
-
Radiotoxicity hazard of U-free PuO2+ZrO2 and PuO2+ThO2 spent fuels in LWR
Progress in Nuclear Energy, 2000Co-Authors: Afroza Shelley, Hiroshi Akie, Hideki Takano, Hiroshi SekimotoAbstract:Abstract The Radiotoxicity hazard of U-free Rock-like oxide: ROX (PuO 2 +ZrO 2 ) and Thorium oxide: TOX (PuO 2 +ThO 2 ) LWR spent fuels is investigated and Radiotoxicity hazard of MOX spent fuel is considered as a reference case. The long-term ingestion Radiotoxicity hazard of ROX spent fuel is one third and nearly one fourth of that of TOX and MOX spent fuels, respectively. This is because the discharged Pu and long lived Np in ROX fuel is less than that of TOX and MOX fuels. In TOX fuel, discharged Pu and MA are lower than that of MOX fuel but the long-term Radiotoxicity hazard of spent fuel is nearly the same as MOX spent fuel. At the cooling 10 5 years, the Radiotoxicity hazard of TOX spent fuel is approximately ten and three times higher than that of ROX and MOX spent fuels, respectively due to higher toxic contribution of 229 Th in TOX spent fuel.
-
Effect of decontamination factor of recycled actinide and FP on the characteristics of SCNES
Progress in Nuclear Energy, 1998Co-Authors: Naoyuki Takaki, Ryuzo Takagi, Hiroshi SekimotoAbstract:Abstract Effect of the decontamination factor (DF) of nuclides to be confined in the closed fuel cycle was examined in terms of the system characteristics. Two kinds of indices, equilibrium mass and equivalent Radiotoxicity, were used to determine the recovery perfectivity of the nuclides. By using the equilibrium mass, extremely high DF had to be attained. The required values of DF were 10 8 for LLFP and 10 12 for actinides. On the other hand, using the Radiotoxicity, inferior perfectivity of recovery, DF=10 6 , could be acceptable for actinides and there is no necessity of LLFP recycling for transmutation because they only have comparable Radiotoxicity with the supplied uranium to the system. The required DF which provide ignorable loss of waste to the outside of the system depends on what index we use. Generalization of index to quantify the hazard or nuisance of nuclear waste and setting the criteria remains unsettled questions.
Afroza Shelley - One of the best experts on this subject based on the ideXlab platform.
-
Radiotoxicity hazard of inert matrix fuels after burning minor actinides in light water reactors
Progress in Nuclear Energy, 2001Co-Authors: Afroza Shelley, Hiroshi Akie, Hideki Takano, Hiroshi SekimotoAbstract:Abstract Ingestion Radiotoxicity hazard index of inert matrix spent fuels are investigated after burning minor actinide (MA) isotopes in LWRs and compared with the hazard index of MOX and MA burning MOX (MOX+MA) spent fuels. As U-free fuels, ROX: (PuO 2 +ZrO 2 ) and TOX: (PuO 2 +ThO 2 ), are considered, in which MA's are added as oxides. The Radiotoxicity hazard index of ROX+MA spent fuel is less than that of TOX+MA and MOX+MA spent fuels due to the lower density of actinides in spent fuel. Some of cooling years the toxic yield of ROX+MA spent fuel is even less than that of MOX spent fuel, if the initial loaded MA in ROX is about 0.5 at %.
-
Radiotoxicity hazard of U-free PuO2+ZrO2 and PuO2+ThO2 spent fuels in LWR
Progress in Nuclear Energy, 2000Co-Authors: Afroza Shelley, Hiroshi Akie, Hideki Takano, Hiroshi SekimotoAbstract:Abstract The Radiotoxicity hazard of U-free Rock-like oxide: ROX (PuO 2 +ZrO 2 ) and Thorium oxide: TOX (PuO 2 +ThO 2 ) LWR spent fuels is investigated and Radiotoxicity hazard of MOX spent fuel is considered as a reference case. The long-term ingestion Radiotoxicity hazard of ROX spent fuel is one third and nearly one fourth of that of TOX and MOX spent fuels, respectively. This is because the discharged Pu and long lived Np in ROX fuel is less than that of TOX and MOX fuels. In TOX fuel, discharged Pu and MA are lower than that of MOX fuel but the long-term Radiotoxicity hazard of spent fuel is nearly the same as MOX spent fuel. At the cooling 10 5 years, the Radiotoxicity hazard of TOX spent fuel is approximately ten and three times higher than that of ROX and MOX spent fuels, respectively due to higher toxic contribution of 229 Th in TOX spent fuel.
-
Radiotoxicity hazard of u free puo2 zro2 and puo2 tho2 spent fuels in lwr
Progress in Nuclear Energy, 2000Co-Authors: Afroza Shelley, Hiroshi Akie, Hideki Takano, Hiroshi SekimotoAbstract:Abstract The Radiotoxicity hazard of U-free Rock-like oxide: ROX (PuO 2 +ZrO 2 ) and Thorium oxide: TOX (PuO 2 +ThO 2 ) LWR spent fuels is investigated and Radiotoxicity hazard of MOX spent fuel is considered as a reference case. The long-term ingestion Radiotoxicity hazard of ROX spent fuel is one third and nearly one fourth of that of TOX and MOX spent fuels, respectively. This is because the discharged Pu and long lived Np in ROX fuel is less than that of TOX and MOX fuels. In TOX fuel, discharged Pu and MA are lower than that of MOX fuel but the long-term Radiotoxicity hazard of spent fuel is nearly the same as MOX spent fuel. At the cooling 10 5 years, the Radiotoxicity hazard of TOX spent fuel is approximately ten and three times higher than that of ROX and MOX spent fuels, respectively due to higher toxic contribution of 229 Th in TOX spent fuel.
Hiroshi Akie - One of the best experts on this subject based on the ideXlab platform.
-
Radiotoxicity hazard of inert matrix fuels after burning minor actinides in light water reactors
Progress in Nuclear Energy, 2001Co-Authors: Afroza Shelley, Hiroshi Akie, Hideki Takano, Hiroshi SekimotoAbstract:Abstract Ingestion Radiotoxicity hazard index of inert matrix spent fuels are investigated after burning minor actinide (MA) isotopes in LWRs and compared with the hazard index of MOX and MA burning MOX (MOX+MA) spent fuels. As U-free fuels, ROX: (PuO 2 +ZrO 2 ) and TOX: (PuO 2 +ThO 2 ), are considered, in which MA's are added as oxides. The Radiotoxicity hazard index of ROX+MA spent fuel is less than that of TOX+MA and MOX+MA spent fuels due to the lower density of actinides in spent fuel. Some of cooling years the toxic yield of ROX+MA spent fuel is even less than that of MOX spent fuel, if the initial loaded MA in ROX is about 0.5 at %.
-
Radiotoxicity hazard of U-free PuO2+ZrO2 and PuO2+ThO2 spent fuels in LWR
Progress in Nuclear Energy, 2000Co-Authors: Afroza Shelley, Hiroshi Akie, Hideki Takano, Hiroshi SekimotoAbstract:Abstract The Radiotoxicity hazard of U-free Rock-like oxide: ROX (PuO 2 +ZrO 2 ) and Thorium oxide: TOX (PuO 2 +ThO 2 ) LWR spent fuels is investigated and Radiotoxicity hazard of MOX spent fuel is considered as a reference case. The long-term ingestion Radiotoxicity hazard of ROX spent fuel is one third and nearly one fourth of that of TOX and MOX spent fuels, respectively. This is because the discharged Pu and long lived Np in ROX fuel is less than that of TOX and MOX fuels. In TOX fuel, discharged Pu and MA are lower than that of MOX fuel but the long-term Radiotoxicity hazard of spent fuel is nearly the same as MOX spent fuel. At the cooling 10 5 years, the Radiotoxicity hazard of TOX spent fuel is approximately ten and three times higher than that of ROX and MOX spent fuels, respectively due to higher toxic contribution of 229 Th in TOX spent fuel.
-
Radiotoxicity hazard of u free puo2 zro2 and puo2 tho2 spent fuels in lwr
Progress in Nuclear Energy, 2000Co-Authors: Afroza Shelley, Hiroshi Akie, Hideki Takano, Hiroshi SekimotoAbstract:Abstract The Radiotoxicity hazard of U-free Rock-like oxide: ROX (PuO 2 +ZrO 2 ) and Thorium oxide: TOX (PuO 2 +ThO 2 ) LWR spent fuels is investigated and Radiotoxicity hazard of MOX spent fuel is considered as a reference case. The long-term ingestion Radiotoxicity hazard of ROX spent fuel is one third and nearly one fourth of that of TOX and MOX spent fuels, respectively. This is because the discharged Pu and long lived Np in ROX fuel is less than that of TOX and MOX fuels. In TOX fuel, discharged Pu and MA are lower than that of MOX fuel but the long-term Radiotoxicity hazard of spent fuel is nearly the same as MOX spent fuel. At the cooling 10 5 years, the Radiotoxicity hazard of TOX spent fuel is approximately ten and three times higher than that of ROX and MOX spent fuels, respectively due to higher toxic contribution of 229 Th in TOX spent fuel.
Hideki Takano - One of the best experts on this subject based on the ideXlab platform.
-
Radiotoxicity hazard of inert matrix fuels after burning minor actinides in light water reactors
Progress in Nuclear Energy, 2001Co-Authors: Afroza Shelley, Hiroshi Akie, Hideki Takano, Hiroshi SekimotoAbstract:Abstract Ingestion Radiotoxicity hazard index of inert matrix spent fuels are investigated after burning minor actinide (MA) isotopes in LWRs and compared with the hazard index of MOX and MA burning MOX (MOX+MA) spent fuels. As U-free fuels, ROX: (PuO 2 +ZrO 2 ) and TOX: (PuO 2 +ThO 2 ), are considered, in which MA's are added as oxides. The Radiotoxicity hazard index of ROX+MA spent fuel is less than that of TOX+MA and MOX+MA spent fuels due to the lower density of actinides in spent fuel. Some of cooling years the toxic yield of ROX+MA spent fuel is even less than that of MOX spent fuel, if the initial loaded MA in ROX is about 0.5 at %.
-
Radiotoxicity hazard of U-free PuO2+ZrO2 and PuO2+ThO2 spent fuels in LWR
Progress in Nuclear Energy, 2000Co-Authors: Afroza Shelley, Hiroshi Akie, Hideki Takano, Hiroshi SekimotoAbstract:Abstract The Radiotoxicity hazard of U-free Rock-like oxide: ROX (PuO 2 +ZrO 2 ) and Thorium oxide: TOX (PuO 2 +ThO 2 ) LWR spent fuels is investigated and Radiotoxicity hazard of MOX spent fuel is considered as a reference case. The long-term ingestion Radiotoxicity hazard of ROX spent fuel is one third and nearly one fourth of that of TOX and MOX spent fuels, respectively. This is because the discharged Pu and long lived Np in ROX fuel is less than that of TOX and MOX fuels. In TOX fuel, discharged Pu and MA are lower than that of MOX fuel but the long-term Radiotoxicity hazard of spent fuel is nearly the same as MOX spent fuel. At the cooling 10 5 years, the Radiotoxicity hazard of TOX spent fuel is approximately ten and three times higher than that of ROX and MOX spent fuels, respectively due to higher toxic contribution of 229 Th in TOX spent fuel.
-
Radiotoxicity hazard of u free puo2 zro2 and puo2 tho2 spent fuels in lwr
Progress in Nuclear Energy, 2000Co-Authors: Afroza Shelley, Hiroshi Akie, Hideki Takano, Hiroshi SekimotoAbstract:Abstract The Radiotoxicity hazard of U-free Rock-like oxide: ROX (PuO 2 +ZrO 2 ) and Thorium oxide: TOX (PuO 2 +ThO 2 ) LWR spent fuels is investigated and Radiotoxicity hazard of MOX spent fuel is considered as a reference case. The long-term ingestion Radiotoxicity hazard of ROX spent fuel is one third and nearly one fourth of that of TOX and MOX spent fuels, respectively. This is because the discharged Pu and long lived Np in ROX fuel is less than that of TOX and MOX fuels. In TOX fuel, discharged Pu and MA are lower than that of MOX fuel but the long-term Radiotoxicity hazard of spent fuel is nearly the same as MOX spent fuel. At the cooling 10 5 years, the Radiotoxicity hazard of TOX spent fuel is approximately ten and three times higher than that of ROX and MOX spent fuels, respectively due to higher toxic contribution of 229 Th in TOX spent fuel.
G. V. Tikhomirov - One of the best experts on this subject based on the ideXlab platform.
-
Residual energy release and actinide and fission product radiotoxicities during long-term storage of high burnup spent VVÉR fuel
Atomic Energy, 2007Co-Authors: B. R. Bergel'son, T. S. Zaritskaya, A. S. Gerasimov, G. V. TikhomirovAbstract:The residual energy release and Radiotoxicity of spent high burnup VVER-1000 fuel during long-term storage is investigated as a function of time. The contributions of α, β, γradiation and Radiotoxicity-the maximum admissible activity of nuclides in air and water-are taken into account in the calculations of the energy release. The data presented can be used to develop methods for handling spent nuclear fuel from prospective power reactors.
-
Radiotoxicity and decay heat power of spent nuclear fuel of VVER type reactors at long-term storage.
Radiation protection dosimetry, 2005Co-Authors: Boris R. Bergelson, A. S. Gerasimov, G. V. TikhomirovAbstract:Radiotoxicity and decay heat power of the spent nuclear fuel of VVER-1000 type reactors are calculated during storage time up to 300,000 y. Decay heat power of radioactive waste (radwaste) determines parameters of the heat removal system for the safe storage of spent nuclear fuel. Radiotoxicity determines the radiological hazard of radwaste after its leakage and penetration into the environment.
-
Radiotoxicity at Final Transmutation of Actinides Accumulated in Transmutation Reactors
Atomic Energy, 2003Co-Authors: B. R. Bergel'son, A. S. Gerasimov, T. S. Zaritskaya, G. V. Kiselev, L. A. Myrtsymova, G. V. TikhomirovAbstract:At the final stage of the existence of nuclear power, when power reactors stop operating and the previously accumulated acitindes have been transmuted, it is necessary to transmute the actinides which were accumulated in the transmutation reactors themselves without makeup by new actinides. During transmutation in thermal reactors with moderate flux density, the Radiotoxicity in the first 10 yr of the final stage of transmutation is due primarily to ^244Cm, which is transmuted rapidly. The next main actinide remaining is ^252Cf. The contribution of ^253Es is 10 times smaller and the contribution of ^246Cm and ^254Cf is 100 times smaller than that of ^252Cf. For transmutation in a reactor with a thermal spectrum and flux density 10^14 sec^–1·cm^–2, the Radiotoxicity decreases over a period of 100 yr by a factor of 150 and by another factor of 10 over a period from 100 to 200 yr. These results show that the final stage of transmutation should be conducted using high-flux transmutation setups which give shorter transmutation times.
-
Radiotoxicity AND RESIDUAL ENERGY RELEASE OF SPENT URANIUM-PLUTONIUM AND THORIUM FUEL DURING PROLONGED STORAGE
Atomic Energy, 2001Co-Authors: B. R. Bergel'son, T. S. Zaritskaya, G. V. Kiselev, L. A. Myrtsymova, A. S. Gerasimov, G. V. TikhomirovAbstract:A computational comparison is made of the Radiotoxicity and residual energy release of spent uranium–plutonium and thorium–uranium nuclear fuel during long-term storage. The contribution of the most significant nuclides, whose primary extraction and transmutation make it possible to decrease energy release and Radiotoxicity of the remaining stored wastes, is determined. 2 figures, 4 references.