Stability of cesium loaded iron phosphate glass : Simulation for nuclear waste immobilization: An FTIR study
The disposal of radioactive wastes generated by the nuclear fuel cycle is among the most pressing and potentially important environmental problems facing the nuclear industry. These wastes will have to be immobilized in suitable host matrices prior to their deposition in geological repositories.
Positron annihilation studies on ODS steel
Oxide dispersion strengthened ferritic/martensitic steels are the candidate structural materials for next generation fission reactors as well as for fusion reactors. As a model system, we have investigated Y2O3 nanoclusters in bcc Iron. Experimental positron annihilation studies on this system showed positrons probing vacancies at interface of Y2O3 and Fe matrix. We have carried out preliminary ab initio computer simulations to obtain energy minimized configuration of a 1nm dia`meter Y2O3 cluster embedded in a bcc-Fe matrix using VASP DFT code. The super cell is constructed with 621 Fe, 13 Y and 24 O atoms along with 20 Fe vacancies at the interface. Figure 1 shows the positron trapping at the relaxed interfacial vacancy cluster, as sketched by yellow globules.