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The objective of this paper is to evaluate the physicochemical properties of electron transfer reaction of semicarbazide and tetrakis (2, 2'-bipyridine)-µ-oxodiiron (III) complex [Fe2O4+] in aqueous acidic media at [H+] = 0.001mol dm-3, µ = 0.3 mol dm-3(NaCl), T = 27 ± 0.5, at max = 520 nm by spectrophotometric method. In the course of the reaction a mole of semicarbazide was consumed by a mole of [Fe2O4+]. The order of reaction is unity dependent on [Fe2O4+] and zero order dependent on semicabazide and is not H+ and µ dependent. Addition of cations and anions did not affect the reaction. There was no intermediate formation when a partially reacted reaction mixture and the solution of oxidant were respectively scanned within a wavelength of 400 - 700nm. Absence of spectroscopic evidence of intermediate complex formation suggests that the reaction proceeds by the outer-sphere mechanistic pathway with ion pair character. [ABSTRACT FROM AUTHOR]

An inversely quadratic Yukawa potential is an exponential-type potential that has received little attention only in the bound state to the best of our understanding. This study obtained the solution of the Schr¨odinger equation for an inversely quadratic Yukawa potential via parametric Nikiforov-Uvarov method and supersymmetric approach. Some thermodynamic properties (vibrational enthalpy, vibrational Gibbs free energy and vibrational entropy) for the Inversely quadratic Yukawa potential are examined. The study is also applied to shannon entropy as the theoretic quantity. The results obtained showed that the energy eigenvalue for the potential goes in the opposite direction with the quantum state and the screening parameter. The Shannon entropy obtained as a function of the potential strength only obeyed the Heinsenberg principle at the ground state and excited states. In both cases, the also satisfied Bialynick-Birula, Mycielski inequality. It is noted that the thermal properties studied as a function of the temperature, even though the studied potential is not a molecular potential, the results followed the trend of the molecular potential. [ABSTRACT FROM AUTHOR]

Inorganic contaminants which consist of toxic metals and salts are notable for their wide environmental dispersion and their tendency to accumulate in the tissues of the human body. Heavy metals are the major inorganic contaminants in abattoir soils. These metals, even at relatively low concentrations, are toxic. Hence the objective of this paper was to determine the concentration of Pb, Hg, Co, V, As, Fe, Cu, Cd, Cr, Mn, Ni, and Zn and their potential sources of pollution in soil from two abattoirs in Itu and Ikot Ekpene Local Government Areas of Akwa Ibom State, Nigeria using appropriate standard methods after the dry oxidation. The concentrations of heavy metals were determined using an atomic absorption spectrophotometer (AAS). The distribution of heavy metals contaminants in the Itu abattoir was of the order Hg < As < V < Cr < Co < Mn < Ni < Pb < Cd < Cu < Zn < Fe, while that of the Ikot Ekpene abattoir was Hg < As < Co < V < Cr < Mn < Pb < Ni < Cd < Cu < Zn < Fe. The mean order obtained for both abattoirs was Hg < As < V < Cr < Co < Mn < Ni < Pb < Cd < Cu < Zn < Fe. The results were subjected to some pollution indices to ascertain the level of ecological impacts on both plants and animals ecosystem around the abattoirs. The contamination factor, geo-accumulation index, degree of contamination, and pollution load index depict no pollution. Generally, all metals investigated were below the permissible limits of DUTCH, FEPA, WHO/FAO, and NESREA. [ABSTRACT FROM AUTHOR]