Routing neptunium to a single product in spent nuclear fuel reprocessing is a significant challenge. In this work, we have further improved the simulation of neptunium extraction in an advanced PUREX flowsheet by applying a revised model of the Np(V)-Np(VI) redox reaction kinetics, a new nitric acid radiolysis model and by evaluating various models for the nitrous acid distribution coefficient....

The gas phase and aqueous thermochemistry and reactivity of nitroxyl (nitrosyl hydride, HNO) were elucidated with multiconfigurational self-consistent field and hybrid density functional theory calculations and continuum solvation methods. The pK(a) of HNO is predicted to be 7.2 +/- 1.0, considerably different from the value of 4.7 reported from pulse radiolysis experiments. The ground-state tr...

Monte Carlo track structure simulation is a powerful method for estimating damage induced by water radiolysis products cell killing. To investigate the influence of multiple ionization formation under 1H+, 4He2+, and 12C6+ ion beams, based on Geant4-DNA was carried out. The G-value H2O2 increased monotonically with increasing linear energy transfer up to 200 eV/nm. Above eV/nm, began dropping, ...

The highest time resolution of the pulse radiolysis had remained about 30 ps since the late 1960’s. To make clear the primary processes in the radiation chemistry and physics within 30 ps, we developed a stroboscopic pulse radiolysis system for the absorption spectroscopy with the time resolution of 2.0 ps (10-90% rise time). The time resolution of 2.0 ps was estimated from the time-dependent b...

Airborne molecular contaminants (AMCs) in cleanrooms should be monitored and controlled tightly to reduce yield loss since they can converted into nanoparticles or surface haze contamination on semiconductor chips masks. Soft X-ray radiolysis was developed detect AMCs as low the ppt-level by forming secondary aerosols from under soft irradiation. However, new particle formation (NPF) using has ...

In this research, the radiation-heterogeneous processes of water decomposition on surface zirconium dioxide nanoparticles (n-ZrO2) were studied. The kinetics buildup molecular hydrogen during radiolytic was also examined. production H2 and H2O2 through radiolysis investigated to develop a computational model disclose kinetic behavior radiolysis. enthalpy ZrO2 studied at temperature range T=1200...

Polyvinyl chloride (PVC), one of the most polymeric materials present in radioactive waste, is exposed to radiooxidation process during disposal and generates many byproducts. Commercial PVC usually contain additives provide desired properties improve their stability shaping lifetime. The generally delay radiolysis limiting formation some transformation compounds, but they can indubitably gener...