Applied Chemistry

Oxovanadium(IV) and Dioxouranium(VI) complexes of Schiff bases derived from 3-substituted-4-animo-5-mercapto-1,2,4-triazole and glyoxal/biacetyl /benzyl have been synthesized and characterized on the basis of analytical and spectroscopic studies. The elemental analysis agrees well with the 1:1 stoichiometry of the type VO.L.So4 and UO2.L.(CH3COO)2 respectively. The IR data suggests that, ligands have coordinated to the metal ion through azomethine nitrogen atoms in a bidentate fashion by keeping sulphur atom of mercapto groups away from coordination. Thermograimetric measurements and XRD pattern have also been done on some oxovanadium (IV) complexes. Some of the VO(IV) and UO2(IV) complexes have been screened for their antimicrobial and antifungal activity. One of the VO(IV) complex has been evaluated for its oxytocic and antihistaminic activity.

The physiochemical properties of the leaf extract of four Nigeria medicinal plants were investigated in order to ascertain their level of safety for human consumption. The results obtained from the analysis show a range of temperature 25.50 + 0.003 , 26.00+0.0020C, as against 30.000C obtained for the water used for the extraction, pH range 5.50+0.003 - 8.0+0.002. All the other extracts showed greenish coloration except Eremomastex polysperman extract that appears bluish purple. Electrical conductivity 24.00+0.012-145.20+ 0.053uscm-1. Suspended solid ranged between 1.60+0.001-3.60+0.008, dissolved solid 12.00+0.003-98.20+0.005, titratable alkalinity and acidity ranged 25.34+0.003-500.00+0.0012 and 40.44+0.005-900.00+0.128mg/l respectively. Biochemical oxygen demand BOD and dissolved oxygen DO values ranged 118.00+0.008-360.00+0.025 and 1.26+0.007-1.50+0.008 respectively. Total hardness ranged from 31.61+0.012 to 48.00+0.015. Finally sulphate, nitrate and chlorides values ranged within 2.10+0.003-24.20+0.004, 2.10+0.005-4.32+0.005 and 30.74+0.025-309.41+0.043 (mg/l). Respectively. The extraction of these leaves in water has strongly altered the entire physiochemical parameter of drinkable water. These variations does not show any definite correlation. However when compared with the WHO permissible level despite the variations over 85% of the values were within the permissible limits. Thus these extract may not pose any danger with respect to physicochemical properties except for acidity. Thus one may apply caution when consuming these extract.

This research studies the surface modification of poly (ethylene terephthalate) (PET) fabric that was induced by DC plasma discharge for nanosiliver treatments. At first, DC plasma discharge was employed systematically as a function of plasma device parameters under different operating conditions including different time, different current and different hydrostatic pressure employing chemically inert argon or nitrogen as a working gas. The optimization of the best of these parameters were performed by the measurements and evaluation of mechanical properties, air permeability and water absorbency, Electron Spin Resonance (ESR) and the surface morphological changes of pretreated polyester fabrics were observed by Scanning Electron Microscope (SEM) photographic analysis , Then the pretreated PET fabric with plasma by the best conditions are subjected to nanosilver treatment by two different silver concentrations .The antibacterial activity of plasma treated and /or nanosilver treated PET against gram positive bacteria (Staphylococcus aurous) and gram negative bacteria(Escherichia coli) were examined. The results obtained showed that both the hydrophilicity and antibacterial behaviours against gram positive bacteria (Staphylococcus aurous) and gram negative bacteria(Escherichia coli) were highly improved by the treatment of fabric by either individual or combined DC cold plasma or nanosilver treatments.

Recent research has shown that the role of food has gone beyond serving as fuel, providing energy needed to perform daily functions, and to maintain the normal metabolic process, but it now provides an opportunity to improve health, reduce the risk of chronic disease and reduce health care cost. Such foods are known as Functional Foods; they provide more than simple nutrition by supplying additional physiological benefits and promoting health to the consumer. In the past decades, the traditional process of isolating bioactive compounds from food is usually very long, tedious and slow , which takes years before tangible results are obtained. The advent of bioinformatics has helped researchers to improve on the purity, yield, time and cost of their search especially in the drug industry but unfortunately not in the food industry, due to lack of specific bioinformatics coded mining tools. A combination of experimental mining and an integrated computational bioinformatics database approach is herein illustrated for the mining of novel bioactive peptides from functional foods.

In case when the the partial pressure of oxygen above its minimum value, it is revealed that the consumption rate of o-xylene is represented by the equation half order with respect to the substrate as well as given the kinetic equation for the rate of accumulation of products of the ammoxidation of xylene on V-Sb-Bi-Cr / ?-Al2O3-oxide catalyst. The kinetic model of process describing the rate of reaction products formation and consumption of reaction products is developed as a result. Constants of the model are calculated.

Coating formulations were developed with diluent or modifiers that remained incorporated as a minority discontinuous phase. Epoxy resins were formed from a DGEBA (diglycidyl ether of bisphenol A), prepolymer (Epikote 828) and MXDA, (m-Xylylenediamine). Butyl laurate (BL) and clay (montmorillonite) were used as the modifier and the filler, respectively. The epoxy network forming systems were prepared by mixing the DGEBA with BL and/or clay and degassed, followed by addition of the MXDA and further degassing. Polymerisation kinetics during epoxy network formations were obtained using Differential Scanning Calorimetry (DSC) on samples of quenched reaction mixtures pre-reacted isothermally at 60 oC at 5 min intervals up to 1 h. The results showed a step-wise increase in Tg and conversion with time. The exothermic process in the clay-filled resins was controlled by the catalytic activity of the clay surface with the resin system.

In this study, a hydrometallurgical treatment for valuable metals recovery from rinsing water of electroplating industries is reported. This water contains high contents of Copper, Nickel, Lead, Zinc and Chromium ions. Copper is recovered by leaching in hydrochloric acid solution. The effects of acid concentration, temperature and treatment time were investigated. Lead and Nickel are removed by adsorption onto activated carbon from artificial binary-component aqueous solutions. The effects of pH, time, temperature, and amount of adsorbent were investigated. Maximum Lead adsorption was obtained at pH 5.5-6 and 80?C for 30 min., while for Nickel at pH 7 and room temperature for 60 min.

To understand the structural and electrical characteristics of Au and thiol substituted tetracene, a quantum chemical calculation has been carried out with Density Functional Theory (DFT) coupled with the Bader’s AIM theory. The various levels of applied electric field (0 – 0.21 VÅ-1) altered the geometrical conformation as well as the electronic energy levels of the molecule. Variations in MPA and NPA atomic charges of the molecule for the applied fields have been compared. The field polarizes the molecule and hence the dipole moment of the molecule increases from 0.0002 to 14.65 D. For the zero bias, the HOMO–LUMO gap is1.752 eV, as the field increases this gap decreases to 1.03 eV, which reveals that it exhibits charge transfer ability for the applied field.

Recently, the synthesis of 2-hydroxybenzoinhydrazone, 2-hydroxybenzoinphenylhydrazone and 2-hydroxybenzoinsemicarbazone with hydrazine hydrate, phenyl hydrazine and semicarbazide hydrochloride in presence of aqueous sodium hydroxide in DMF-water (80%) medium respectively. Similarly, furoinhydrazone, furoinphenylhydrazone, furoinsemicarbazone were synthesized by the interactions of furoinbenzoin with hydrazine hydrate, phenyl hydrazine and semicarbazide hydrochloride in presence of aqueous sodium hydroxide in DMF-water (80%) medium respectively. The synthesis of 2-hydroxybenzoin and furoinbenzoin were carried out by the known literature method. The structure of all the synthesized compounds were justified on the basis of chemical characteristics, elemental and I.R. and NMR spectral analysis.Benzoin hydrazone and its metal complexes were synthesized from substituted benzoinhydrazone. They were characterized by elemental analysis and spectral analysis. The synthesized complexes were screened for antimicrobial activity. At a concentration of 1000µgm/ml. Which was serially diluted to determine their MIC value .

Methyl-2-dihydroxyphenylsulfide was synthesized with the aim of characterizing antioxidant action. Its ability to break off oxidation chain in the reaction with peroxide radicals, as well as parameter of f•k which characterizes inhibiting activity of inhibitor, were studied.