http://repository.unn.edu.ng/handle/123456789/448 Wed, 02 Sep 2026 18:14:24 GMT 2026-09-02T18:14:24Z http://repository.unn.edu.ng/handle/123456789/7839 Effect of Some Organic Wastes on the Biogas Yield From Carbonated Soft Drink Sludge Uzodinma, E.O; Ofoefule, A.U; Eze, J.I; Mbaeyi, I; Onwuka, N.D Biogas, a relatively cheap energy source, was produced from carbonated soft drink sludge (CS) and its blends. The carbonated soft drink sludge was blended with organic wastes such as palm oil sludge (POS), soybean cake waste (SW), powdered rice husk (RH) and pig dung (PD). The wastes were combined in the ratios of CS:POS (1.2:1), CS:SW (2.6:1), CS:RH (1.2:3) and CS:PD (1: 1.8). They were subjected to anaerobic digestion for 25 days. The mean biogas yield of CS alone was 7.1 L/ total mass of slurry input. while those of CS:SW, CS:PD, CS:RH and CS:POS were 11.6, 9.7, 7.7 and 3.5 L/ total mass of slurry input respectively. Results of the investigation indicated that there was increased biogas production from the combinations of CS:SW, CS:PD and CS:RH though the increase in yield of the CS:RH was not significant (p 0.05). The biogas yield from CS:POS was very low. Quantitative analysis of the flammable biogas from some of the blends indicated high methane contents. The CS:POS had methane (76.5%), CO2 (20.1%), CO (2.2%), H2S (1.2%), CS:SW had methane (71.9%), CO2 (20.8%), CO (7.1%) and H2S (0.2%) and CS:RH had methane (73.6%), CO2 (18.4%), CO (7.5%) and H2S (0.2%). The overall results indicate that the low yield of flammable biogas from carbonated soft drink sludge could be enhanced significantly when blended with either soybean cake waste or pig dung. Mon, 01 Sep 2008 00:00:00 GMT http://repository.unn.edu.ng/handle/123456789/7839 2008-09-01T00:00:00Z http://repository.unn.edu.ng/handle/123456789/7838 Experimental and Quantum Chemical Studies on the Corrosion Inhibition Potential of Phthalic Acid for Mild Steel in 0.1 M H2SO4 Ameh, P. O; Koha, P.U; Eddy, N.O The corrosion inhibition potential of phthalic acid for mild steel in 0.1 M sulphuric acid was studied using experimental (weight loss, gasometric, FTIR and Scanning electron microscopy) and theoretical (semi empirical, Ab initio and DFT) approaches. Results obtained from weight loss measurements indicated that phthalic acid inhibited the corrosion of mild steel and recorded average and instantaneous maximum inhibition efficiencies of 55.48 and 87.34% at 303 K and at a concentration of 0.1 M respectively. Thermodynamic/adsorption considerations revealed that the adsorption of the inhibitor is exothermic, spontaneous and supported the mechanism of physical adsorption. The adsorption behaviour of the inhibitor was best described by the Langmuir adsorption model. FTIR spectra obtained from the corrosion product of mild steel in the absence and presence of the inhibitor revealed the existence of interaction between the inhibitor and the metal surface due to some shifts in the functional groups of the compound after adsorption. Scanning electron micrographs of the corroded metal (in the absence and presence of the inhibitor) revealed that phthalic acid prevented the corrosion of mild steel by forming protective coverage on the surface of the metal. Calculated quantum chemical parameters were found to be in good agreement with those reported for some good corrosion inhibitors. Although results obtained from Ab initio calculations for condensed Fukui functions were slightly at variance with those obtained from DFT calculations, considerations of Huckel charges on the atoms of the molecule, bond length, HOMO and LUMO molecular orbital plots clearly supported DFT results which indicated that the sites for nucleophilic and electrophilic attacks corresponded to atoms O(11) and C(4) respectively. Sun, 01 Mar 2015 00:00:00 GMT http://repository.unn.edu.ng/handle/123456789/7838 2015-03-01T00:00:00Z http://repository.unn.edu.ng/handle/123456789/7834 Kinematic Model for Asymmetry: Projected Hotspot/Lobe Advance Speed Onuchukwu, C. C.; Ubachukwu, A.A; Odo, F. C. We present a kinematic model for asymmetries in radio sources, which enabled an estimation of the projected hotspot/lobe advance speed for high-luminosity radio sources using the arm-length ratio (Q) and apparent flux ratio (R). We obtain a mean projected speed along the line of sight h i = 0.15±0.05 for all the sources in our sample, using the Q parameter and hi 0.12 − 0.32 for = 2 + 1 (where is the electron energy spectrum index) using the R parameter. Our results indicate that the adopted model of brightness evolution of plasma element affects the values of projected speed. Regression analyses indicate that the estimated speeds using the Q and R parameters show some correlation with distance (L) and luminosity (P), especially for quasars. Tue, 17 Dec 2013 00:00:00 GMT http://repository.unn.edu.ng/handle/123456789/7834 2013-12-17T00:00:00Z http://repository.unn.edu.ng/handle/123456789/7832 Potential Health Risk Assessment of Heavy Metals [Cd, Cu And Fe] Concentrations in Some Imported Frozen Fish Species Consumed in Nigeria Ukoha, P.O; Ekere, N.R; Udeogu, U.V; Agbazue, V.E The concentrations of three heavy metals [Cd, Cu and Fe] were determined in three species of imported frozen fish widely consumed in Nigeria. Appropriate weights of the dried pulverized fish samples were digested following FAO/SIDA wet digestion method with HNO3 and H2O2 [1 : 1]. The accuracy and precision of the determinations in the study were evaluated using LOD, LOQ and certified standard reference material [DORM-1 for Dog fish]. The human health risk of consumption of the fishes was assessed by calculating the daily exposure rates (D), hazard quotients (HQ) and the total hazard indices (THI) of the metallic toxicants. The chemical analysis results showed that the concentration levels of the elements are of the ranges of 0.001-0.150 mg/Kg; 1.05-12.06 mg/Kg and 8.21 to 85.06 mg/Kg for Cd, Cu and Fe, respectively. Also results of the potential health risk assessment showed that the total hazard index of all the toxicants indicated no risk status from the consumption of the fish species studied. Tue, 01 Apr 2014 00:00:00 GMT http://repository.unn.edu.ng/handle/123456789/7832 2014-04-01T00:00:00Z