No description available.

No description available.

No description available.

No description available.

No description available.

No description available.

There has been a strong international interest in using pyroprocessing to close the fast nuclear reactor fuel cycle and reprocess spent fuel efficiently. To commercialize pyroprocessing, safeguards technologies are required to be developed. In this research, the use of Self-Interrogation Neutron Resonance Densitometry (SINRD) has been investigated as a method to safeguard the process and more precisely quantify the 239Pu content of pyroprocessing materials. This method uses a detector array with different filters to isolate the low-energy resonance in 239Pu neutron fission cross section. The relative response of the different detectors allows for the quantification of the amount of 239Pu in the pyroprocessing materials. The Monte-Carlo N-Particle (MCNP) code was used to design a prototype SINRD instrument. This instrument is composed of a neutron source pod and a SINRD detector pod. Experimental measurements were also performed to validate the MCNP model of the instrument. Based on the results from simulations and experiments, it has been concluded that the MCNP model accurately represents the physics of the experiment. In addition, different SINRD signatures were compared to identify which of them are usable to determine the fissile isotope content. Comparison of different signatures allowed for reduction in the uncertainty of the 239Pu mass estimate. Using these signatures, the SINRD instrument was shown to be able to quantify the 239Pu content of unknown pyroprocessing materials suitable for safeguards usage.

This thesis reports the functionalization of metal nanoparticles to allow for solubility in organic solvents used in solar cell fabrication. Functionalization of the nanoparticles using poly(ethylene glycol) methyl ether thiol (PEG-SH) allows for the phase transfer of the nanoparticles from aqueous solution to organic solvents. Once functionalized it was found that nanoprisms will undergo a shape change. This change in morphology was investigated using UV-Vis measurements, transmission electron microscopy (TEM), and X-ray Absorption Near Edge Structure (XANES) measurements and a mechanism for the shape degradation is presented. The PEG functionalization procedure can be applied to other types of metal nanoparticles and once soluble, these particles were incorporated into the active layer of the BHJ cells. It has been found that the PEG functionalized particles do not improve the cell efficiency, but they do affect the cell performance. The addition of the particles does not influence the open circuit voltage, but it does affect the current density of the devices. This suggests that the particles may be acting as electron traps, not allowing current to flow efficiently through the device. This shows that while the PEG-ylation of the particles is effective at solubilising them into useful organic solvents, the thickness of the PEG layer on the nanoparticles may not provide protection from electrons and allow for effective charge transfer throughout the solar cell.

No description available.

No description available.