Browsing by Author "Azeez, Taofik Oladimeji"
Now showing 1 - 13 of 13
Results Per Page
Sort Options
Item Open Access Diffusivity and kinetics model for biodegradation of PAHs in a saturated porous matrix(Scholarlink Research Institute Journals, 2014) Azeez, Taofik Oladimeji; Arinkoola, Akeem Olatunde; Salam, Kazeem Kolapo; Nwakaudu, Madueke StanleyThe commercial implementation of biodegradation of polycyclic aromatic hydrocarbons (PAHs) as a bioremediation technique against physical process was due to lack of its effective and efficient diffusivity model with reaction parameters in a saturated porous matrix. The development and simulation of diffusivity model which involve reaction kinetics was aimed to provide quantitative insight on biodegradation of PAHs. The developed model obtained from the principle of conservation of matter, concepts of Fick’s law of diffusion, Malthus equation and Monod kinetics expression under isothermal condition was simulated with experimental data. The result showed that Corynebacterium sp and Pseudomonas putida were effective and PAHs exhibits pseudo first order reaction. Though, the effective diffusivity of PAHs decreases as degradation of PAHs proceeds with increased microbial mass concentration at increased penetration depth. The developed diffusivity model has been shown to be effective and not only providing quantitative insight into biodegradation of the PAHs but serves as an alternative option in the selection of microbes capable of facilitating the restoration of PAHs contaminated sites.Item Open Access Effect of chemical agents on morphology, tensile properties and water diffusion behaviour of hibiscus sabdariffa fibers(IISTE, 2016) Azeez, Taofik Oladimeji; Onukwulii, Dominic OkechukwuEffective utilization of Hibiscus sabdariffa fibers in composites applications as a reinforcing fibers in polymer matrix have been a major concern due to its poor mechanical and hydrophilic properties. It will be of benefits to environmental and technological advancement, if its properties are properly handled. In this study, the morphological, tensile and water absorption characteristics of H. sabdariffa fibers was aimed to be investigated. H. sabdariffa fibers was modified using sodium hydroxides, sodium lauryl sulphate and ethylene diamine tetraacetic acid. The morphology using scanning electron microscopy, tensile properties (strength, modulus, elongation and energy at break), water absorption and water diffusion behaviours were studied. Chemical modifications improved fiber surface and roughness, tensile strength and modulus, elongation and energy at break with reduced water absorption of H. sabdariffa fibers. The water diffusion behaviour is less - Fickian controlled by water penetration rate. Hence improved the hydrophobic nature of H. sabdariffa fibers.Item Open Access Effects of the chemical treatment of avocado pear wood filler on the properties of LDPE composites(Carl Hanser Verlag GmbH & Co. KG, 2019) Government, Rabboni Mike ; Ani, Kingsley Amechi; Azeez, Taofik Oladimeji; Onukwuli, Dominic OkechukwuItem Open Access Improving the unsaturated polyester matrix through commingled with chemically treat cissus populnea fibers(U. P., 2017) Azeez, Taofik Oladimeji; Onukwuli, Dominic OkechukwuThe extent of improvement of chemically treated Cissus populnea fiber on morphology, mechanical, adhesion, and water sorption behaviors in Cissus populnea fiber/UPE composites was aimed to be investigated. Fibers were treated with sodium hydroxide (NaOH) and sodium lauryl sulphate (SLS), respectively. The composites were prepared by hand laying techniques of treated and untreated fibers with unsaturated polyester matrix (UPE) using response surface methodology with central composites design of DoE software. The mechanical properties (tensile strength, tensile modulus, flexural strength, flexural modulus, hardness and impact strength) were optimized. The interfacial shear stress (IFSS) using fiber pull-out method, scanning electron microscopy (SEM), density, and water sorption behavior using power law with Fickian diffusion law were studied at optimum level. The optimization of mechanical properties as dependent with factors (weight fraction of the fiber and weight fraction of the matrix) using RSM with CCD technique was done to avoid waste of materials and confusion on properties of the composites. Treatment of Cissus populnea fiber with NaOH and SLS, respectively, improved the tensile and flexural properties of the composites. NaOH treatment gave the best tensile strength while best flexural properties was achieved with SLS treatment. SEM images revealed the morphological changes caused by NaOH and SLS, respectively, at optimal composites production to corroborate interfacial adhesive between Cissus populnea fiber and UPE matrix on composite properties. NaOH and SLS treatments, respectively, reduced the water saturation point with less Fickian behaviour and increased water diffusion coefficient of the composite.Item Open Access Influence of chemical surface modifications on mechanical properties of combretum dolichopetalum fibre-high density polyethylene (HDPE) composites(U. P., 2018) Azeez, Taofik Oladimeji; Onukwuli, Okechukwu Dominic; Walter, Peter Echeng; Menkiti, Mathew ChukwudiMaximizing the use of natural fibres as ecofriendly materials in polymer composite applications reduces its threat posed to human through increased biomass in the environment. In this study, the effect of chemical surface modifications using acetic anhydride and sodium hydroxide solution on the mechanical properties of Combretum dolichopetalum fibre-HDPE composites was aimed to be investigated. Fibres were treated with 6 % acetic anhydride and 12 % NaOH solutions for 30 minutes at room temperature based on optimum treatment conditions after water retting extraction process, then, the composites were prepared. The mechanical properties (tensile strength, tensile modulus, flexural strength, flexural modulus, hardness and impact strength) of the C. dolichopetalum fibre reinforced HDPE matrix composites and scanning electron microscope analysis were studied. C. dolichopetalum fibre was not only effective as reinforcement of HDPE matrix but mercerization and acetylation of C. dolichopetalum fibre ultimately enhanced the mechanical properties of HDPE composites. Scanning electron microscope analysis revealed that HDPE matrix possess better adhesive interaction with acetylated and mercerized C. dolichopetalum fibre compared with untreated C. dolichopetalum fibre at ultimate tensile strength.Item Open Access Kinetics of degradation of anthracene by the activity of corynebacteria sp and pseudomonas putida in contaminated water(Bio IT Journals, 2012) Azeez, Taofik Oladimeji; Owabor, C. Ngozi; Nwacha, RichardThe environmental threat of anthracene to humans on exposure through industrial effluent discharged and other combustion activities into the environment with expensive nature of the physical and chemical remediation techniques initiates this research. The kinetics of degradation of anthracene by the activity of Corynebacterium sp and Pseudomonas putida for the liberation of the anthracene contaminated water was aim to be investigated. The enriched inoculums of Corynebacterium sp and Pseudomonas putida was separately inoculated into anthracene contaminated water at room temperature of 280C under an optimum pH of 7.2 for 96hours, thereby decreased the anthracene content in the water. About 95.2% of anthracene was degraded by Corynebacterium sp while about 93.5w/w% of anthracene was degraded by Pseudomonas putida. The biodegradation kinetics parameter evaluated indicates that both Corynebacterium sp and Pseudomonas putida were favourable for bioremediation of anthracene contaminated water but Corynebacterium sp was preferred due to higher proportion of anthracene utilized.Item Open Access Mercerized milletia sp fiber epoxy composites: Fiber loading, aspect ratio and mechanical properties(U. P., 2018-06) Uzondu, Francis Nnamuzie; Onukwuli, Dominic Okechukwu; Azeez, Taofik Oladimeji; Osoka, C. Emmanuel; Obibuenyi, John IfeanyiThe fiber loading capacity and poor adhesion between fibers and matrix remains an area of concern in fiber polymer composites. The fiber loading capacity and aspect ratio of mercerized milletia sp fiber on mechanical properties (tensile strength, tensile modulus, tensile toughness, elongation, flexural and impact strength) of Milletia sp fiber epoxy composites was investigated. Milletia sp fiber was extracted using water retting approach. The extracted fiber was mercerized at optimum treatment conditions of 5.84 wt% NaOH and 42.58mins. The epoxy composite samples were prepared using hand layup method for epoxy 103 and amine hardner in a ratio 2: 1 and commingled with untreated and treated fiber, respectively, at optimum treatment conditions. The fiber loading of 10 – 50 wt% and aspect ratio of 42.68 – 213.38 mm/mm were used. The mechanical properties of mercerized milletia sp fiber epoxy composite were determined and optimized using RSM of MATLAB statistical tool box. The tensile strength, tensile modulus, toughness, elongation, flexural strength and impact strength for epoxy resin was 44.2 MPa, 1.9716 GPa, 0.8177 MPa, 3.1%, 85.4 MPa and 360 Kj/m2, respectively. At optimum aspect ratio and fiber loading, the mercerized milletia sp fiber increased the tensile strength, tensile modulus, toughness, elongation, flexural strength and impact strength of the epoxy resin by 46.38, 77.75, 97.99, 18.81, 125.06 and 217.78%, respectively. Thus, mercerized Milletia sp fiber enhanced the mechanical properties of epoxy composites.Item Open Access Nutritional and electrolyte values of cnidoscolus aconitifolius (Chaya) leaves consumed in Niger Delta, Nigeria(U. P., 2013) Iwuji, Samuel Chidi; Nwafor, Arthur; Azeez, Taofik Oladimeji; Nwosu, Emmanuel Chibuike; Nwaokoro, Joakin Chidozie; Egwurugwu, Jude; Danladi, Nygan BalaEvaluation of the nutritive and electrolyte values of edible plants is currently essential for human nutrition and safety. This work assessed the proximate and mineral composition of the leaves of Chaya plant (Cnidoscolus aconitifolius) consumed in Niger Delta Nigeria for medicinal and nutritional purposes. Chaya is commonly known in this southern area of Nigeria as ‘hospital is too far’ or ‘ogwu obala’. The study showed that the dried leaves of the plant contain 47.03 ±1.02% of nitrogen free extract; 33.04± 3.14% of crude fibre; 7.03±0.23% of crude fat; 4.03±0.67% of crude protein, while moisture and ash made up 6.10±1.10% and 3.04±0.32%, respectively. A gram of the dried leaves yielded (in mg) 10±1.2, 20±1.6, 0.01±0.1, 100±5.3, 85±4.32, 18±2.1 and 50±2.3 of Iron, Phosphorus, Sodium, Potassium, Magnesium, Manganese and Calcium, respectively. The energy yield of the leaves was 258±4.5kcal/100 mg. These results suggested the comparative richness of the leaves in fibre, high nitrogen free extract (carbohydrate) and essential minerals. Properly prepared leaves are therefore recommended for daily consumption in order to supplement the recommended daily intake of nutrients and minerals and hence prevent nutritional and electrolyte deficiency disorders.Item Open Access Optimization and characterization of the properties of treated avocado wood flour-linear low density polyethylene composites(Elsevier B.V. on behalf of Faculty of Engineering, Alexandria University, 2019) Government, Rabboni Mike; Onukwuli, Okechukwu Dominic; Azeez, Taofik OladimejiAbstract The research was carried out to investigate the optimization of surface modification for avocado wood flour (ACWF) and the characterization of the treated and untreated of avocado wood flour–linear low density polyethylene composite (ACWF-LLDPE). The variation of treated filler on the mechanical and water sorption properties was investigated. The untreated and treated ACWF-LLDPE composite was characterized using scanning electron microscopy (SEM) and Fourier transform infrared (FTIR). Central Composite design of response surface model (RSM) was used to forecast the mechanical and water sorption properties of ACWF-LLDPE composite. The properties of ACWF-LLDPE composite was statistically analysed and found to be significant. The optimal treatment was particle size of 100 mesh and filler content of 22.97%. At optimum particle size and filler content, the mechanical properties were 24.972 MPa tensile strength (TS), 6.195% elongation (E), 0.863 GP a tensile modulus (TM), 62.664 MPa flexural strength (FS), 0.809 GP a flexural modulus (FM), 699.918 Pa Brinell hardness (BH), and 91.619 kJ/m2 impact strength (IM). The corresponding water sorption (WS) at this condition was 3.338%.Item Open Access Optimization of biodegradation of anthracene by corynebacterium sp and psuedomonas putida(U. P., 2015-05) Azeez, Taofik Oladimeji; Owabor, Chiedu Ngozi; Nwakaudu, Madueke Stanley; Usondu, Nnamuzie FrancisThe carcinogenic potential of industrial effluent discharged of anthracene on the ambient environment with contamination to soils and aquifers is not only environmental concern but difficulty in implementation of biodegradation of anthracene due to inability to optimizing the process parameters. The optimization of process parameters for biodegradation of anthracene with the activity of Corynebacterium sp and Pseudomonas putida using response surface methodology was aimed to be investigated. A 23 of full factorial central composite design was employed for developed quadratic polynomial model to achieve optimal performance of the process. Statistically, high correlation coefficient (R2) for quadratic polynomial model for biodegradation of anthracene by activity of Corynebacterium sp 0.9659 (p<0.05)and Pseudomonas putida 0.9939 (p<0.05) were obtained. The optimum conditions for anthracene degradation by Corynebacterium sp were 69.99g/L, 83.20hours and 3.4735vvm with about 98.48 percent of anthracene degraded while Pseudomonas putida were 69.989g/L, 3.58hours and 3.5vvm with 89.51percent of anthracene degraded.Item Open Access Proxy model for optimization of biodegradation of pyrene by corynebacterium sp and pseudomoas putida(U. P., 2015-11) Azeez, Taofik Oladimeji; Owabor, Chiedu Ngozi; Nwakaudu, Madueke Stanley; Opebiyi, SampsonA proxy model for optimization of operating conditions (pyrene concentration, biodegradation time and aeration) for biodegradation of pyrene by Corynebacterium sp and Pseudomonas putida was aimed to be investigated. The proxy model for biodegradation of pyrene with activity of Corynebacterium sp and Pseudomonas putida was developed from experimental data using response surface methodology (RSM) with central composite design (CCD) of the design of experiments software. Corynebacterium sp degraded 96.71 % of pyrene at optimal conditions of 68.16 mg/L of pyrene concentration, biodegradation time of 82.57 hours and aeration condition of 3.0125vvm, while Pseudomonas putida degraded 93.84 % of pyrene at optimal conditions of 69.90 mg/L of pyrene concentration, biodegradation time of 84 hours and aeration condition of 3.4995 vvm. The developed proxy model of biodegradation of hazardous pyrene disposal under the stated operating conditions is fit and acceptable for optimization.Item Open Access Recombinant phosphoinositide-3-kinase C2β C2 domain molecules(IISTE, 2017) Banigo, Alma Tamunonengiofori; Azeez, Taofik OladimejiRecombinant DNA domain remains a dependant of effective use of recombinant proteins in many applications but its production remains an area of concern due to DNA vector and production path. This work is aimed at studying the generation and replication of the recombinant DNA molecule using PI3K C2β C2 domain and glutathione s-transferase (GST) which expressed in pGEX-2T vector. The molecular cloning technique was employed to generate a recombinant DNA molecule. PI3K C2β C2 domain of isoform PI3K C2β belonging to class PI3K C2 of Phosphoinositide-3-Kinase (PI3K) family was used and the effective digestion of pGEX-2T vector was studied using restricted enzymes (RE) of EcoR I and Sma I with binding partners location. The ligated product of recombinant DNA was obtained after successful doubled digestion of pGEX-2T vector. The best transformation of competent bacterial cells was obtained at molar ratio of 5:1 for RE digested vector insert DNA and vector DNA. The recombinant DNA can be employed may be used in treatment of non – communicable diseases such as cancer and diabetes.Item Open Access The impact of mentoring programs for sustainable career development and work/life balance in Biomedical Engineering profession - Short communication(U. P., 2019) Banigo, Alma Tamunonengiofori; Iwuji, Samuel Chidi; Ezelote, Judith Chinelo; Azeez, Taofik OladimejiThe socio-economic, technological and emotional imbalance remains an issue of individual growth in career development and work-life balance. The impact of mentoring programs for sustainable career development and work and lifestyle balance in biomedical professions was examined. Career development was studied using self-assessment, career awareness, performance, skill acquisition, goal setting and work-life style balance. Career development can be achieved with pleasure if the essential routes were addressed by the parties involved in mentoring programs. Proffered solution of organizational support, social support, use of modern facilities and self-assessment were recommended as tools for mentoring programs that reduced pain, depression, friction and wear, and emotional stress of mentors and mentees. Thus, provide an outstanding strength of social, economic, technological and emotional output as well as good healthy conditions for career development and stable work-lifestyle to achieve a set goal and target in biomedical engineering profession based on action plans.