Thesis (Ph. D.)--University of Hong Kong, 1984.

Thesis--Ph. D., University of Hong Kong, 1982.

Thesis (Ph. D.)--University of Hong Kong, 1988.

Thesis (Ph. D.)--University of Hong Kong, 1990.

Page 20 missing from the thesis. / <p> This work was undertaken to evaluate neutron activation analysis as a technique for simultaneous determination of Ru and Os in sulfide minerals by counting the γ radiation of 97Ru and 103Ru, and the β^-radiation of 191Os and 193Os. The samples studied were collected from the Strathcona and Frood-Stobie Cu-Ni sulfide deposits of Sudbury. Sulfide minerals, including pyrrhotite, chalcopyrite, pentlandite and cubanite were separated from samples including representatives of both ore grade and non-commercial material. The minerals were analysed for Ru and Os to determine their concentration ranges in these sulfides, the degree of geochemical coherence of the metals in sulfides from both high grade ore zones and weakly mineralized rocks and their distribution between coexisting sulfides.</p> / Thesis / Master of Science (MSc)

Yes / Metal nanocrystals offer new concepts for the design of nanodevices with a range of potential applications. Currently the formation of metal nanocrystals cannot be controlled at the level of individual atoms. Here we describe a new general method for the fabrication of multi-heteroatom-doped graphitic matrices decorated with very small, ångström-sized, three-dimensional (3D)-metal crystals of defined size. We irradiate boron-rich precious-metal-encapsulated self-spreading polymer micelles with electrons and produce, in real time, a doped graphitic support on which individual osmium atoms hop and migrate to form 3D-nanocrystals, as small as 15 Å in diameter, within 1 h. Crystal growth can be observed, quantified and controlled in real time. We also synthesize the first examples of mixed ruthenium–osmium 3D-nanocrystals. This technology not only allows the production of ångström-sized homo- and hetero-crystals, but also provides new experimental insight into the dynamics of nanocrystals and pathways for their assembly from single atoms. / We thank the Leverhulme Trust (Early Career Fellowship No. ECF-2013-414 to NPEB), the University of Warwick (Grant No. RDF 2013-14 to NPEB), the Swiss National Science Foundation (Grant No. PA00P2_145308 to NPEB and PBNEP2_142949 to APB), the ERC (Grant No. 247450 to PJS), EPSRC (EP/G004897/1 to RKOR, and EP/F034210/1 to PJS) and Science City (AWM/ERDF) for support. We thank the Wellcome Trust (Grant No. 055663/Z/98/Z) for funding the Electron Microscopy Facility, School of Life Sciences, University of Warwick. We also thank COST Action CM1105 for stimulating discussions, Thomas Wilks for supplying the micelle image for Figure 1, and the Australian Synchrotron and the University of Monash for allocation of time on the SAXS/ WAXS beamline and funding. The 2000FX Gatan Orius digital TEM camera used in this research was funded by Science City: Creating and Characterizing Next Generation Advanced Materials, with support from Advantage West Midlands and part funded by the European Regional Development Fund.