The purpose of this study is to provide groundwork for future autoradiographic investigations using 33P as a tracer.

Ninety square planar Rh(I) complexes of the type cis-[Rh(CO)₂(X)(L)], [Rh(COD)(X)(L)], [Rh(CO)₂(L)₂]ClO₄ and [Rh(COD)(L)₂]ClO₄ (X is Cl or Br; COD is 1,5-cyclooctadiene; L is aniline, pyridine, pyridine N-oxide, imidazole and ammonia), as well as their isotopically labelled derivatives (¹³CO, ²H and ¹⁵N) were prepared, characterized by microanalysis and melting point, and investigated by the following spectroscopic techniques: infrared, Raman, ultraviolet, mass spectrometry, and 1H, ¹³C and ¹⁵N nmr spectroscopy. The comprehensive isotopic labelling studies allowed unambiguous assignment of the infrared modes in the 4000-50 cm⁻¹ region. The infrared assignments are discussed with reference to their vᴰ/Vᴴ ratios, the various ligands and halogens used, the charges on the complexes, and are compared to similar compounds. The 1H, ¹³C and ¹⁵N nmr runs were performed at room and low temperatures. Fluxionality of the ligands (L) was observed and the exchange process was monitored by variable temperature nmr. The enthalpy and entropy values for the intermolecular exchange of L in the complexes cis-[Rh(CO)₂(X)(L)] were obtained by a complete computer simulated band shape analysis of the carbonyl region of the ¹³C nmr spectra. The non-equivalence, and specific assignment of the carbonyl groups in the cis- [ Rh(CO)₂(X)(L)] complexes were determined by recording the variable temperature ¹³C nmr spectra of the doubly enriched species cis[Rh(¹³CO)₂(X)(¹⁵N-ligand)]. ²J(¹³C-Rh-¹⁵N) values are reported for the first time. The ¹J(¹⁵N-¹⁰³Rh) coupling constants are rationalized in terms of the metal-nitrogen bonding, and correlate with the s-character of the bonding electron on nitrogen. While the solution electronic spectra reveal that the complexes are discrete monomeric entities in solution, there are indications of metal-metal interactions in the solid-state. The normal coordinate analysis study of the complexes cis-[Rh(CO)₂(X)(L)] involved the calculation of a general valence force field by applying the eigenvector method of Becher and Mattes. The results show that point-mass-modelling and simplified force field, as assumed in our treatment, describes, to a good approximation, the vibrational properties of the complexes. The potential energy distribution provided further support for the proposed infrared assignments of the complexes.

>Magister Scientiae - MSc / In this study a complete set of exclusive (~p; 2p) polarization transfer observables of closed-shell oxygen isotopes are calculated using both direct and inverse kinematics using the relativistic plane wave impulse approximation. The interaction matrix is written in terms of the SPVAT (scalar, pseudoscalar, vector axial vector, tensor) covariants where each amplitude is obtained directly from experimental phase shifts. A relativistic mean eld theory approximation is used to compute boundstate wave functions of the nucleons. We study the evolution of polarization transfer observables within oxygen isotopes and identify observables which may discriminate between these isotopes. The same kinematical conditions are considered for both direct and inverse kinematics: the incident energy is set at 504 MeV and coplanar angles are xed at (22:12 ;􀀀40:30 ). The results indicate that only three spin observables, namely, Ay, P and Dnn distinguish di erent oxygen isotopes at these kinematical conditions in the inverse kinematics.

Tap water supply is an essential resource for human societies. However with increasing water use and global warming, this resource needs to be monitored and managed sustainably. Here we use stable isotopes to identify potential issues associated with tap water resources in Canada. We analyze isotopes of 576 tap water samples collected from across Canada and classified them based on their supply sources including groundwater (TapGroundwater), river (TapRiver) and lake (TapLake). We found, isotopic values in tap water correlate strongly with those predicted in local precipitation across Canada, suggesting precipitation is the parent source of tap water. However, this correlation is stronger for TapGroundwater and TapRiver than TapLake. To explain this difference, we constructed a series of water balance models to predict isotopic values of surface water across Canada validated against Canadian rivers isotopes data. We then compared the tap water isotopic values to those predicted in local surface water, which improved the predictability of TapRiver and TapLake but not TapGroundwater. We suggest, TapGroundwater usually reflects isotopic values of annually averaged precipitation whereas TapRiver and TapLake reflect post-precipitation processes. We used the residuals between our observed and predicted isotope data to assess regional sources and processes influencing tap water isotopes across Canada. Regionally, snow/glacier melt from the Rockies contributes to groundwater recharge across Western Canada as well as to some rivers and lakes in Alberta and British Columbia. Also, tap water are highly evaporated across Western Canada irrespective of their sources. Across the Great Lakes and East Coast regions, lakes undergo high evaporative losses. Also, many localities in the East Coast pump and store groundwater in small lakes or ponds exposing them to evaporation. Our data and models provide a baseline for isotope monitoring of tap water resources and isotope forensic studies across Canada.

A dissertation submitted to the Faculty of Science, University of the Witwatersrand, Johannesburg, in fulfilment of the requirements for the degree of Master of Science. Johannesburg, November 2014. / Unable to load abstract.

The stable isotopes carbon and nitrogen from 18 skeletal and 51 dental samples from various burial contexts at the Bronze and Iron Age sites of Mitrou and Tragana Agia Triada are examined to understand diet in prehistoric central Greece. The samples are compared by cultural period, site, and burial type in order to determine if diet was affected by changes in society or by social status as determined by burial form. In addition, isotopic data from across Greece is compared to understand diet from the Neolithic to Iron Age and in different regions of the country. The results of the Mitrou-TAT study indicate no change in diet through time or between the two sites. No significant differences were found between diet and burial types as well. When applied to the broader aspect of societal change, these results suggest that, even with a significant societal change, diet is not significantly influenced.

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