The mutual diffusion coefficients, activation energy for diffusion, surface concentration and surface tension of the liquid Cd-Ga alloys have been calculated throughout the concentration range using energetics obtained from the theoretical model fits of the experimental thermodynamic data. Our calculations show that Cd-Ga liquid alloys showed immiscibility at a temperature of 723 K between 0.4 and 0.5 atomic fraction of Cd. Within this concentration region and temperature, the mutual diffusion coefficients approached zero values and the activation energy for diffusion reached high peak values of 220 J/mol. It was also observed that within the region of immscibility, the diffusion coefficients do not obey Arrhenius relation over a wide range of temperature.

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Gross alpha and beta activity concentrations in soil, cassava and fluted pumpkin (leaf and stem) were investigated using a gas flow proportional counter. The gross alpha activity concentrations for the fluted pumpkin were between 3.55 and 13.95 Bq/Kg and 3.53 and 3.61 Bq/Kg for the leaves and stems, respectively. The gross alpha activity concentrations for cassava and soil samples ranged from 0.07 to 0.60 Bq/Kg and 0.35 to 0.53 Bq/Kg, respectively while the gross beta activity concentrations ranged from 0.43 to 0.89 Bq/Kg and 0.46 to 1.04 Bq/Kg for the cassava and soil samples, respectively. The gross alpha and beta activity concentrations in cassava, fluted pumpkin and soils samples have been determined using alpha/beta spectroscopy. The result of thestudy showed that the Iva-valley coal mine area has lower gross alpha and beta activity concentrations compared to other areas of the country. This shows that the coal mining activities in the area may not have increased the radiation burden of the area.

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The influence of the strong heterocoordination tendency of the Li-Pb liquid alloy on its surface properties has been studied using a statistical thermodynamic model based on compound formation and that based on the layered structure near the interface. In addition to the already proposed saltlike structure Li 4 P b compound formed in the liquid alloy, the study shows that the compound Li 3 P b also has a profound influence on the thermodynamic properties of the liquid alloy. The surface study suggests that the formed compounds in the liquid alloy segregates to the surface about 0.8 atomic fraction of Li. The calculated surface tension of the liquid alloy exhibits a pronounced hump above equiatomic composition.2