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Potentiometric investigations of complexes formed by chromium (III) ion and amino acids have been carried out. The dissociation constants of the amino acids, the stepwise formation constants and the overall stability constants of the metal ions and amino acids complexes were determined. The dissociation constants of the amino acids determined are; alanine (10.29), arginine (12.02), asparagine (9.39), glycine (9.87), histidine (7.01), lysine (9.28), methionine (9.68), phenyalanine (9.61), proline (10.53), threonine (10.31), tryptophan (9.77), and valine (10.28).

The exploitation of supported metals and metallic oxides catalysts is increasingly becoming an issue of special interest in the petroleum industry. This is consistent with necessary need for mitigating separation, recycling and reusability problems coupled with increased production costs associated with free metals, unsupported or homogeneous catalyst systems.

This paper examines the interactions between two spheres in an unbounded fluid. Using bispherical coordinates, no-slip and far-field boundary conditions, an exact solution of Stokes equations for the translational motion of two spheres of arbitrary size and arbitrary orientation with respect to their directions of motion are obtained. This solution is in form of truncated infinite series. The various hydrodynamic forces exerted on the spheres are calculated.

This paper addresses the problem of reliability improvement of k -out of - n system. It first looks at how series system is improved through the improvement of individual components with most reliable components. It also used redundancy (cold and hot) to improve the series system reliability.

A study was conducted on growth and yield of cowpea (Vigna unguiculalta L) under different mulch materials on an Alfisol in the Teaching and Research farm of Ambrose Alli University, in Ekpoma, Nigeria. Mulch materials increased the soil pH, organic carbon, total nitrogen, available phosphorus and carbon exchange capacity of the soil over control. At 3 and 6 weeks after planting, cocoa husk and empty fruit bunch recorded significant higher plant height, leaf area and number of leavers of cowpea plant over cassava peels and control.

Methanolic extracts of leaf, stem and root of Acalypha wilkesiana were investigated with the goal of establishing its acclaimed potency as an anthelmintic and antimicrobial agent. Antimicrobial assay was carried out using the agar cup plate diffusion method. The extracts were tested against 8 human pathogenic microorganisms (5 bacteria and 3 fungi). The leaf and stem methanol extracts exhibited antibacterial and antifungal activities.

Methanolic extracts of the leaves of Phyllanthus amarus and stem of Phyllanthus muellerianus were studied for antileishmaniasis activity, phytotoxicity and cytotoxicity. The antileishmanial activity was evaluated in vitro using promastigote culture of Pakistani leishmanial strain (L. major) in 96 well micro titer plate bioassay, while phytotoxicity was assessed using the Lemna bioassay and cytotoxicity using brine shrimp lethality assay. Methanolic extract of stem of P.

Members of the genus Echinops are now widely used in treating brain disorders, ophthalmic problems, chronic fever, pains in the joints and inflammations. They are aphrodisiac and are used for treating pregnant women. The Nigeria species have not been discovered in this way. The plants are therefore being suggested to our scientists, chemists and agriculturists for possible screening for drug development. Cytomorphological studies on 4 taxa distributed in 3 species of the Echinops have been studied.

Comparative assessment of the soil and vegetation in a municipal dumpsite at Iguomo, Benin City, Nigeria at different distances from the dumpsite was carried out. An area of 30m2 was marked out and divided into three plots of 10 m2 each and these were designated as plots A, B and C. An area of 10 m2 was also taken at a distance of 100m away from the dumpsite, it served as the control plot or plot D. Population sampling was done to determine the species diversity across the plots. Soil samples were collected from each plot and microbial and physico-chemical analyses were carried out.

The indiscriminate discharge of the wastewater generated during the processing of Manihot esculenta Crantz into the environment or public sewers remains a source of concern. In this study, the acute toxicity (96-h LC50) of cassava effluent was evaluated using Clarias gariepinus juveniles and Egera radiata. The two organisms were exposed to different concentrations of the effluent using a renewable static bioassay with continuous aeration. The LC50 of exposed C. gariepinus juveniles was found to be 1.92 ml/L with lower and upper confidence limits of 1.35 ml/L and 2.19 ml/L, while that of E.