Applied Chemistry

This study is aimed at assessing & comparing the levels of some heavy metals in most commonly sold and/or consumed soft and alcoholic drinks in Iwo, Osun State, Nigeria. Three brands each of soft drink (Coke, 7Up & Maltina) and alcoholic drinks (Orijin, Trophy & Goldberg) were bought and analyzed for copper, chromium & lead using Flame Atomic Absorption Spectrophotometric technique. 30 mL of each of the sample was digested, after allowing the sample to stand for 24 hrs for gas evaporation, using dry ashing method; 10 mL of concentrated HNO3 was added to the ash, filtered and made up to 30 mL mark with 0.1 M HNO3. The digested samples were analyzed for Cu, Cr & Pb using Buck Scientific Model 210VGP Flame Atomic Absorption Spectrophotometer. Results showed that overall mean levels of Cu were 0.05 ± 0.03 mg/L and 0.09 ± 0.04 mg/L for soft & alcoholic drinks respectively. Chromium was below detection limit of the FAAS and can be inferred to be below tolerance limit set by NIS (0.05mg/L). Lead was detected in both sampled drinks at a concentration ranging from 0.010 - 0.140 mg/L for soft drinks and

The polymeric membrane using naturally occurring aloe-vera pulp as host and for filler, fine powdered natural waste egg shell was used which served the purpose of second component of the composite. The ratio of the aloe pulp and egg shell (ES) was kept 90:10. The membrane was characterized by different spectroscopic methods, viz., X-ray diffraction, Fourier transformed infra-red spectroscopy and conductivity by impedance spectroscopy. There is a sharp increase in the resistivity with temperature around melting temperature of the crystalline polymer. The attraction of this work is that the ingredients used for constructing the polymer matrix are natural , biocompatible and fully biodegradable.

The synthesis and Biological activity of 2,4,5-trimethoxy benzaldehyde Thiosemicarbazone ligands have been reported. The Infrared and Elemental analysis have been assigned. The data agree quite well with the proposed structures. The group sensitive fundamentals are compared with those of similar molecules already reported in the literature. Ligand were screened for antimicrobial activities by the disc diffusion technique using DMSO as solvent. These Schiff base has been studied for their anti-bacterial ,anti-fungal, and anti oxidant activity. The antifungal activity of the said ligand has been screened against Aspergillus flavus, Asperjillus niger and Antibacterial activity tested against Vibrio harveyi , VibrioVulnificus, Escherichia Coli, Bacillus pumilus.The anti oxidant activity againt catalase assay.

The Corrosion inhibition of a inhibitor namely Zn complex of 1-(8-hydroxy quinolin-2yl-methyl) urea (Zn-HUF) in controlling corrosion of mild steel immersed in aqueous solution containing 60 ppm Cl- has investigated using weight loss method. The corrosion inhibition efficiency offered by 50 ppm of Zn-HUF is 74 %. The corrosion inhibition was observed due to the formation of more stable and compact protective film on the metal surface. Fluorescence spectral analysis was used to detect the presence of iron-inhibitor complex. Polarization study and Electrochemical Impedance spectra confirm the formation of a protective film formed on the metal surface.

A new heteropolyacid-based cation exchanger [Bismuth(III) tungstomolybdate (BTM)] has been synthesized and characterized using chemical stability, pH titration, distribution studies, thermal stability, FTIR, X-Ray analysis and TGA curve analysis. It exhibits 1.05 meq/g ion exchange capacity for sodium ions. The chemical stability of the material has been tested in acidic, neutral and basic media. Its distribution behaviour for nine metal ions has been studied. Ion exchanger column was used for binary separation and hardness causing metal ions removal.

The study includes the determination of Ni (II) using azo reagent Benzenesulfonate, 4,4’-[3-(2-pyridinyl)-1,2,4-triazine-5,6-diyl]bis-, hydrogen sodium salt (1:1:1) spectrophotometric at (?max 562 nm) wave length. The effect of different parameters on determination is evaluated. The study shows that best PH=(7±0.1). The study includes obey concentration of Beer-Lambert law to determination of the calibration graph of Ni(II) by reagent. From this graph we note obey the concentration of law was between (2-50) µg of Ni(II) after this values the absorbance increased. The stoichiometry of complex Nickel ion determined by molar ratio method. Result indicated reagent to metal ratio was (1:2) the stability constant of the complex determination through mole ratio method and its value indicated good stability. The UV-Vis spectra and the IR spectra of the complex and reagent were measured. From all mentioned studies proposed structural formula of Ni(II) complex.

The ligand 2,5-bis(phenylcarbamoyl)terephthalicacid (bpctpa) was synthesized and characterized. Novel co-ordination polymers were prepared by using ligand (bpctpa) and transition metal ions viz. Mn(II), Co(II), Ni(II), Cu(II), and Zn(II). The co-ordination polymers and parent ligand were characterized by elemental analysis, spectral studies, thermogravimetry, number-average molecular weights ( ), diffuse reflectance spectral studies and magnetic susceptibilities. The biological activity of all the samples has also been monitored against plant pathogens.

The individual use of these pharmacologically active substances which generate great but underappreciated levels of other toxicologically potent and associated bioactive metabolites through purposeful and inadvertent discharge to the environment via excreta and by illegal disposal has become a global issue. This work reviews aspects of drugs occurrence, metabolism, transport routes, stability, analysis and environmental distribution of these emerging contaminants and highlights current developments in investigating and monitoring their fate and potential effects in aquatic environments. Gas chromatography-mass spectrometry (GCMS) and high performance liquid chromatography are the preferred methods for trace drugs analysis in wastewaters as their measurements depend largely on successful application of a fast and reliable method for qualitative and quantitative determination. The application of this method to the actual influents, effluents, sludge and environmental sediments from sewage treatment works (STWs) allows the assessment of drugs content and the extent at which STW helps in the transport of these pollutants (via different media) into the environment. The capability is also outlined for furthering our understanding of fate and behaviour of drugs with particular reference to illicit drugs, abused pharmaceuticals and environmental processes in our quest to understand the overall issues of drugs and make available exposure data for the aquatic realm.

The inhibitive action of Tagetes erecta-leaves (TEL) extract on mild steel in 1M HCl has been studied using weight loss, electrochemical polarization and AC impedance measurements and The extract shows a very good inhibition in the hydrochloric acid medium and inhibition efficiency of the extract was found to vary with the extract concentration and immersion time. The maximum inhibition efficiency of 96% was obtained at 0.3%v/v concentration of the extract at 24h immersion time at room temperature. The potentiodynamic polarization data showed that the extract is of mixed type. EIS measurements showed that the dissolution process occurs under activation control. The protective film formed on the surface of mild steel by the adsorption of phytochemical constituents present in the extract was confirmed by SEM studies

Direct and rapid procedures for the electrothermal atomic absorption spectrophotometric determination of Bi, Sb, and Cd in different biological samples using a multi-element electrothermal atomic absorption spectrometer (Perkin-Elmer SIMAA 6000) are described. Two kinds of modifiers; Pd(NO3)2 + Mg(NO3)2 mixture modifier and Ir-permanent modifier were tested. For Seronorm urine, Lyphocheck urine, Bovine liver, Pig kidney, Pork liver, and Tea, the samples were diluted (1:4, v/v), (1:1, v/v), (1:9, v/v), (1:29, v/v), (1:3, v/v), (1:4, v/v), respectively, with 0.2% HNO3 which were then introduced directly into the furnace. The detection limits were 0.90-1.5 µg.l-1 for Bi, 0.79-1.3 µg.l-1 for Sb, and 0.01-0.025 µg.l-1 for Cd. The Characteristic masses were 73.3-88 pg for Bi, 46.3-67.7 pg for Sb, and 1.7-3.3 pg for Cd. The reliability of the procedures is checked by analyzing certified reference materials. A standard additions method was used to determine Bi, Sb, and Cd in the samples simultaneously. Results of analysis of standard reference materials were in agreement with certified values.