Modern Scientific Press

ABSTRACT: Spices are widely used in Nigeria for cooking as food condiments or taste enhancing substances, some of which are locally made by different tribal groups. They are also used in many parts of the world for cooking, processing of foods or other applications. In this study, an analysis of four heavy metals: Fe, Cu, Cd, and Pb was done by FAAS technique. Eight spice samples namely: maggi star, curry powder, thyme, mr. chef, royco, ajino-motto, indomie spice and fermented locust beans were analyzed for these heavy metals. The ajino-motto sample had the highest concentration of Fe and Cu while the highest concentration of Cd was observed in the fermented locust bean sample. All the analyzed samples had Cd levels that breached the international standard by WHO. Pb however, was not found in any of the samples which is good to know. Fe and Cu fall below the maximum permissible limits by WHO. Though, some of the values of Cd are slightly above WHO limit, it generally implies that consumers of these spices should be cautious.

ABSTRACT: Analysis of limestone samples from 4 selected areas in Nigeria as a potential raw material for production of Portland cement has been carried out. By means of Thermogravimetric Analysis (TGA) and Differential Thermal Analysis (DTA) the decomposition of calcium carbonate were revealed at 853.36ºC; 827,01ºC; 796.12ºC and 545.10ºC respectively. The X-ray florescence revealed that the Kalambaina limestone has SiO2 15.31%; Al2O3 4.29%; Fe2O3 2.16%; CaO 42.85%; MgO 1.58%; CaCO3 76.50% and LOI 33.42%; Kware limestone has SiO2 24.86%; Al2O3 7.48%; Fe2O3 4.34%; CaO 31.41%; MgO 2.06%; CaCO3 56.09% and LOI 28.43%; Amanawa limestone has SiO2 41.50%; Al2O3 15.78%; Fe2O3 7.43%; CaO 15.28%; MgO 1.78%; CaCO3 27.30% and LOI 17.34% and Maiyama limestone has SiO2 48.40%; Al2O3 20.52%; Fe2O3 9.53%; CaO 6.72%; MgO 1.38%; CaCO3 12.01% and LOI 12.33%. The mineral composition Ca, Mg, Fe, Cu, Cr, Pb, Na and K were determined for the samples and it was observed that their amount were within the minimum levels for use in the industrial production of Portland cement.

ABSTRACT: The phenomenon “error” is such a sensitive phenomenon in sciences and chemistry in particular due to its impact to lives, processes and studies and so the quest to completely eradicate or minimize errors. In this work, we report some molecules whose experimental proton affinity values are suspected to have shrouded some errors. These molecules include: NO, OF, SF6, CH3Br, CH3Cl, and CH3SH. Quantum chemical calculations methods which have been used to accurately determine the proton affinity values for different molecular species in our previous studies are applied in this study to calculate the proton affinity values for theses molecular species with experimentally measured proton affinity values. In each of the systems, the large disparity between the experimentally measured PA values and the ones determined via the different quantum chemical calculation methods suggest possible errors in the experimentally reported values.