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Transmutation of long-lived radioactive materials such as fission products (LLFPs) is one of attractive options of fast reactors utilization, and it has some possibilities to decrease radioactive waste and to minimize long term environmental burden.Especially, transmutation of radiotoxic nuclides in LLFPs such as Tc-99(2.13x105 years) and Ⅰ-129(1.57x107 years) will enable to remove a radiotoxic risk from human surroundings effectively.In this study, two types of new moderated LLFP target pins in the subassembly were proposed for increasing transmutation rate of Tc-99 and Ⅰ-129 for fast reactor.Nuclear characteristics such as transmutation rate were evaluated for the new target pins.The possibility of fabrication of the new target pins was also studied.The target pin for Tc-99 is consisted of moderator pellets such as ZrH2 and many needle-shaped Tc-99 materials embedded in the pellets.The needle-shaped Tc-99 materials are arranged uniformly in the ZrH2 body to reduce the self-shielding effect by the neuron absorption of Tc-99.The target pin for Ⅰ-129 accommodates pellets of ZrH2 or ZrD2 mixed with BaI2.In the study, a typical fast reactor core has been assumed for transmuting LLFPs generated in its own driver fuels.The LLFP target assemblies are located at the core peripheral region.The number and the diameter of the needle materials and the diameter of the moderator pellet have been optimized with a Monte Carlo code MVP.The composition of ZrH2 or ZrD2 and BaI2.were also optimized to increase transmutation rates of Ⅰ-129.The transmutation rates of Tc-99 and Ⅰ-129 reach about 9%/year.The fabrication experiment of BaI2-ZrH2 composite has been also performed.BaI2 powder and ZrH2 powder were mixed, pressed and then heated to make a pellet-shaped composite.As the results, it is cleared that the content of BaI2 in BaI2-ZrH2 composite and the size of BaI2 powder were very important for fabrication of BaI2-ZrH2 composite.The proposed composite transmutation forms of Tc-99 and Ⅰ-129 have high potential to realize efficient transmutation of LLFPs..