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The study investigated the effect of feeding high and low saturated fatty acid based diets to feed female albino rats (Rattusnorvegicus) with a view to evaluating the effects of the fatty diets on the feeding patterns, weight and body composition of the rats. Seven months old female Rattus norvegicus were used for the experiment. The weights of the rats were taken for twelve weeks using Salter balance (Model 250). Four experimental diets were formulated which were made up of 2.5 and 5.0 g of margarine (blue band), 2.5 and 5.0 g canola oil each mixed with the basal diet. The control diet was grower feed and the resultant experimental diets were fed to the experimental rats kept in cages at the rate of 12 rats per cage. The rats were fed with the diets at the rate of 3% of body weight for a period of twelve weeks. The highest weight gain was recorded in the group fed with 5.0 g margarine, followed by 5.0 g canola, 2.5 g margarine, 2.5 g canola and least in the rats fed the control.The mean weight gain of the rats fed with 5.0 g margarine and 5.0 g canola were significantly different (p<0.05) from the mean weight of 2.5 g margarine, 2.5 g canola and the control. The food intake of the rats fed 5.0 g margarine and 5.0 g canola was also significantly different (p<0.05) from the food intake of rats fed 2.5 g margarine, 2.5 g canola and the control. The proximate composition of the carcass of the rats fed the different experimental diets showed that fat content of the rats fed 5.0 g margarine was higher than in the rats fed the other diets. The histology of the liver of rats fed 5.0 g margarine and 5.0 g canola showed greater fat accumulation in the rat’s liver compared to rats fed 2.5 g margarine, 2.5 g canola as well as the control. Rats with the highest body weight gain were considered obesity-prone; those with the lowest body weight were regarded as obesity-resistant while others were considered intermediate. The study concluded that the kind of fat consumed contributes to the weight gained by the rats.

This work synthesized and characterized chitosan-silica based hybrid fiber from cowry shell and rice husk respectively with the aim of studying the behavior of a hybrid polymer-silicate composite via the electrospinning technique to produce nanofibers from natural polymer and agro waste, from which scaffolds can be produced which can be used for culturing and wound healing application in the biomedical field. The samples obtained were subjected to the following analyses: Energy Dispersive X-ray Florescent (ED-XRF), Fourier Transform Infrared Spectroscopy (FTIR), X-Ray Diffraction (XRD), Scanning Electron Microscopy (SEM) and Thermogravimetic Analysis (TA).It was observed from the ED-XRF analysis that the major constituent of rice husk ash is silica (SiO2) with some associate metallic oxides. The peaks obtained from the FTIR analysis of the polymer confirm the characteristics features for the polysaccharide structure of chitosan while the characteristic and positions of the peaks observed in the extracted silica spectra showed similar position with that of the commercially available silica obtained from BDH chemicals UK. The Chitosan-silica hybrid has Si AOH and Si AO ASi with the respective bands within the regions of 3270-3400cm-1 and 989-1300cm-1.The X-ray diffraction analysis indicates the presence of crystallite in polymers which usually results to improve mechanical properties, unique thermal behavior, and increased fatigue strength. These attributes make crystalline polymers desirable materials for biomedical applications. Also, amorphous components of the hybrid composite would present an improved biodegradation behavior of a biomedical material. It was observed from the morphological analysis that there was good interfacial interaction between the chitosan and the dispersion of the silica reinforcement material. The TA of the sample was carried out to investigate the effect of silica reinforcement on the thermal stability of the hybrid composite. It was discovered that the reinforcement of the silica matrix and its reaction with the polymer makes the thermal resistance of the hybrids to increase and hence, increase in thermal decomposition temperature.

This work investigated the suitability of the utilization of cowry shell-based hydroxyapatite (HA) in orthopaedic and dental applications. HA was synthesized via aqueous precipitation process and sintered at different temperatures. The pH and density of the synthetic HA were determined before subjecting the samples to mechanical characterization. The chemical analysis of the HA was carried out with the aid of Energy Dispersive X-ray Florescence (ED-XRF), Atomic Absorption Spectrophotometer (AAS), Fourier's Transform Infrared Spectroscopy (FTIR) and X-ray Diffraction (XRD) while the microstructural analysis was evaluated using Scanning Electron Microscopy (SEM) and Energy Dispersive Spectroscopy (EDS).The weight of the precipitate produced at pH 9 and 10 are similar to the theoretical HA which is 8.17 g per precipitation batch assuming complete transformation of Calcium (Ca) to HA while the weight recovered at the pH 10 to 12 are greater than the theoretical value and this might be due to the presence of adsorbed water layers on the surface of the powder at the corresponding pH. The density of the synthetic HA is in the range of 2.66-3.75 glcm3 which falls within the theoretical density of HA. The HA has the optimum hardness value of 742 HV at 900oC. The compressive strength obtained ranges from 252.20-452.5 MPa while the optimum compressive strength is 452.5 MPa at 1200oC. The tensile strength obtained is in the range of 55.84 to 86.41 MPa. The optimum value being 86.41 MPa was obtained at 1200oC and this falls within the range of the tensile strength of dense HA. The range of the elasticity of the synthetic HA is 30.83-65.05 G Pa and it was observed that the elasticity of the material increases as the sintering temperature increases. The value obtained is higher than the modulus of bone and that of human tooth but falls within the range of value of a dense HA. The fracture toughness obtained ranges from 0.65 -2.55 MPam1/2. The optimum value of the fracture toughness which is 2.55 MPam1/2 at 1200oC is within the range of the fracture strength of human compact bone. The ED-XRF and AAS reveal that the main component of the synthetic HA powder are calcium and phosphorus. It can be deduced from the FTIR that the synthetic sample is hydroxyapatite. Observation from the XRD patterns shows that the material is a crystalline single phase with large amount of amorphous phase which is good because amorphous components present an improve biodegradable attributes. Pure HA and other phases in minute concentration were observed in the XRD results. The SEM analysis of the HA material shows that the particle size of the material has a high dispersion. It can be observed that the images of the synthesized hydroxyapatite are porous in nature and this porous nature is a good desirable property of material for bone substitute. The EDS technique reveals that the elemental constituent of the synthesized HA was obtained to be Ca 55.25 wt%, P 26.91 wt% and O 17.84wt% which implies high purity of the calcium phosphate produced through th...

This study investigated the de-phosphorization, de-sulphurization and de-mineralization of roasted pre-treated Koton-karfe iron ore by atmospheric organic acid leaching with the aim of upgrading the iron ore to concentrate and super-concentrate for use in indirect and direct iron making processes, respectively. The work involved chemical and mineralogical characterization, roasting pre-treatment and particle size analysis of the iron ore as-received, as-roasted and as-leached. The ore as-received and as-roasted at 750˚C was subjected to factorial design based atmospheric organic acid leaching at fine and coarse particle sizes of 75 and 475µm; low and high contact times of 30 and 90 minutes were observed. Operation carried out at concentrations of 0.2 and 1.0 M at temperatures of 30 and 90˚C. The leaching was carried out in single and multistage. XRF analyses were carried out on all the samples. The leaching sequence of H2O-HCOOH-H2O was found to produce the highest grade of the iron ore concentrate in the multistage leaching. The results of the XRF analysis showed that as-received Koton-karfe iron ore contains; 43.45, 0.0246, 0.098 weight % of iron, phosphorus, Sulphur respectively. The as-roasted Koton-karfe iron ore contains; 46.91, 0.012, 0.05 weight % of iron, phosphorus, Sulphur, respectively and roasted-leached with formic acid in multistage contains; 67.89, 0.00123, 0.001 weight % of iron, phosphorus, and Sulphur. The results obtained indicates that the % purity of the iron content in the roasted-leached Kotonkarfe iron ore was increased by 56.25 weight %, while the deleterious phosphorous, Sulphur and silica contents were drastically reduced by 95.00, 98.98 and 80.85 weight %, respectively. The iron content of the roasted-leached sample of 67.89 weight % satisfy the specifications of 63 and 67% Fe minimum content for iron ores for both in-direct and direct iron making processes, respectively. The research has thus shown that hydrometallurgical leaching process is an efficient beneficiation route for the separation of iron oxide from other gangue oxides in the Koton-karfe iron ore. It can also be deduced that the roasting process significantly enhanced the leaching removal of sulphur, phosphorus and other gangue materials in the ore. Thus, the pre-roasting leaching process has significantly reduced the undesirable phosphorus, sulphur and silica content in the ore and increased the iron metal value in the ore rendering it suitable for both the blast furnace process in Ajaokuta and the Midrex reduction operation at Aladja.