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Item Open Access Development of an institutional-based community power pooling model for seamless renewable energy integration(Federal University of Technlogy, Owerri, 2023-10) Opara, Raymond OkechukwuIn recent times, educational institutions were provided with sources of power, that were able to cater for their needs, cognizance of the low demand for knowledge economy was not high. As a result, the available energy was able to suffice for the limited schools, departments, and units within the university system that was available as at that time. As technology continues to improve, the quest for knowledge increases thereby giving needs for expansion in the educational institutions, which cut across creating of more administrative sections, departments and courses. This expansion came with the need for more energy consumption, which calls for a more robust technology with enabling energy integration. The universities were not taking into consideration using energy resources within their operating environments for optimal utilization. And even when there is any consideration to the use of renewable energy resources, standalone energy systems were readily attracted without consideration to network, and integration model, with a fear of un-seamless nature of renewable energy resources. To mitigate the aforementioned shortcoming, this project proposes an institutional-based community power pooling model with seamless renewable energy integration. This involves the formulation and development of an institutionalized local distribution network forming a mini – grid. Then appropriate dc and ac Load Flow (LF) model were applied to determine an optimal balance between locally available distributed energy resources (DERs) and co – located load centers with the referenced institution – in this case, FUTO. The model simulations reveal that the system is capable of synchronizing the renewable energy resources within the university in a single network bus, alongside with public power supply and diesel generators. This could guarantee efficient and optimal utilization of the energy potentials within the university community, with excess energy of 8,603,334 KWh/yr. available for sales to the neighbouring energy users from the formulated model. This model could be utilized in other universities across the nation with the view of tailoring its architecture to suit each institutions special peculiarities in terms of energy resources and load demand.Item Open Access Development of intelligent master controller for hydridized power pool system applications(Federal University of Technlogy, Owerri, 2022-11) Kufre, Esenowo JackThe development of an intelligent master controller model for hybridized power pool system applications has become necessary in the contemporary society where much resources are allocated in a decentralized scenario which does not encourage high productivity. Many metropolitan cities are endowed with several scattered energy resources within its locality and when aggregated in a power pool, its energy resources aggregation for continuous energy supply in order to curtail energy wastage may likely be posed with the challenges associated with uncoordinated system. In view of this therefore, an Intelligent Master Controller (IMC) is proposed to oversee and regulate the unified energy potentials in some metropolitan cities in order to ensure efficiency, reliability, and optimal utilization. In the conceptual framework deployed in this study, Afikpo Metropolis was used as a case study to demonstrate a typical power pool architecture with the intelligent master controller. The network voltage level for the five experimented communities were used with respect to the available energy sources. Programmable Logic Controller (PLC) was adopted for the renewable energy synchronization and hybridization through virtual demonstration; the integration of their hybridized renewable energy sources with other available sources like the public power supply and the generating system were made possible through intelligent master controller. The intelligent master controller operation sequence was simulated with proteus software. The hardware was implemented with electronics components, whereas the remote monitoring and control was achieved with Hypertext Mark Language (HTML), Cascaded Style Sheet (CSS), JavaScript and Hypertext Preprocessor (PHP) design. The HTML, CSS and JavaScript provide an app for human and machine interactivity, and MongoDB gives the data documentation platform, whereas the ThingSpeak gave the real time analytical scheme for the system. The result from the software simulation conformed with that of the hardware implementation which reveals that energy from metropolitans’ cities could be centrally monitored and controlled using intelligent master control model. This model was demonstrated remotely through the web/Android App, and the energy generated and consumed by the pooled communities were documented in the cloud. The system performance was validated within 6hours of operation, and the system reliability prediction was carried out to ascertain the model functionalities. The developed intelligent master controller model was stable, observable and controllable from the MATLAB simulation result.Item Open Access Development of an intelligent traffic management system using dynamic time allocation technology(Federal University of Technlogy, Owerri, 2024-06) Nwaogwugwu, Nnanyereugo Kelechi ClintonConsidering the increase rate at which traffic congestion occur in urban cities which is associated with longer waiting time of vehicles on traffic queues as well as loss of productivity, fuel, time, fatigue and other health-threatening conditions; it is imperative to apply innovative, fully functional and affordable technologies to curb this challenge. Unfortunately, state-of-the-art traffic management systems are not able to solve this problem as they do not employ intelligent traffic control techniques at road junctions. This research developed an intelligent road traffic management system using Dynamic Time Allocation Technology (DTAT). In doing this, Modelio, an open-source Unified Model Language (UML) tool, was utilized in conjunction with object-oriented system analysis and design in analysing and modelling of typical traffic scenario at road junctions. A sensor network for the detection of vehicular presence and movement was designed using motion sensors and IP cameras. Furthermore, a camera system for capturing vehicle plate number of offending drivers, as well as traffic offence SMS gateway for communicating with offenders and appropriate authorities was developed. Fuzzy Logic and Artificial Neural Network (ANN) techniques as well as load balancing and remote procedural call (RPC) were applied in implementing the fundamental operations of the system. The system was simulated using Proteus 8 Professional in which a microcontroller was used to run the fuzzy logic operations, while the ANN runs on the data storage server and was used to analyse the patterns of stored data so that the system can learn traffic situations of the road with time. Results obtained indicate that the frequency at which traffic flows at a particular lane of the road within a period of time is a function of the number of vehicles that enter and leave the traffic zone at that point. Performance of the developed system shows that there is a balance in the flow of traffic for different lanes of the road intersecting at a point.Item Open Access Optimization and control of solar-powered telecommunication network base stations in Nigeria using standalone bifacial photovoltaic system(Federal University of Technology, Owerri, 2025-10) Osuji, Christopher UcheThis thesis compared the potentials of using two different configurations of photovoltaic systems; Monofacial Photovoltaic (MFPV) Panel, and Standalone Bifacial Photovoltaic (BFPV) panel to generate electricity that will meets energy requirement of a mobile telecommunication base based on theoretical mathematical modelling, simulation, and optimization using PVsyst version 7.4.8 and Hybrid Optimization Model for Electric Renewables (HOMER) software. In achieving this, six off-grid telecommunication base station sites at different geographical site were selected which include; Imo (Umuagwo, 4.33 kWh/m2/day), Kwara (Oje, 5.97 kWh/m2/day), Sokoto (Kiso, 5.81 kWh/m2/day), Rivers (Chokocho, 4.76 kWh/m2/day), Lagos (Kwame, 4.50 kWh/m2/day), and Borno (Baje,5.51kWh/m2/day). Research gaps covered are: space constrains, poor power output, and CO2 emission etc. associated with MFPV, generator, and battery system. Therefore, different configurations of standalone systems of MFPV panel with generator and battery backup and the proposed BFPV module with battery backup were studied and compared for energy optimization to determine the most economically feasible system that conforms to less Carbon IV Oxide (CO2) emission and cost minimisation. The Net Present Cost (NPC) and total CO2 generated were used as indices for measuring the optimization level of each energy configuration, and the option with the highest optimal value was considered to be the best energy solution for telecom base station. Results obtained shows that the installation cost of the MFPV panel, Battery, and the generator is N1, 288,000.00/Wp and the total yearly cost is N483, 200.00/Wp/Yr. The used energy cost is N4, 597,964,800.00/kWh which is the Levelized cost of energy (LCOE). The net present value of the project is –N7, 731,200.00 and the return on investment is -750.3%. On the other hand, the LCOE for installing BFPV panel system is N95,184.64.00/kWh. The net present value of the project is N266, 895,136 and the return on investment is 55191.3%. This shows that the adoption of BFPV panel installation at TBs is profitable. This result is a validation of the objective of this research. Environmentally, CO2 emission in using BFPV systemen is 0.25tons/W while that of installing MFPV system is 102tons/W. Consequently, there is a reduction of CO2 emission (101. 75) by adopting the BFPV system.Item Open Access Design and modelling of smart home technologies for the aged persons(Federal University of Technlogy, Owerri, 2021-07) Okorafor, Godfrey NwajiSmart home technology for the aged persons here is a wireless sensor-based home system that provide the aged persons a safe, sound and secure home environment, while enabling them to live independently in their own homes as long as possible. The aged persons here are that population within the ages of 65 years and above. Nowadays, the rapid increase in the number of aged persons, including those with disabilities, the decrease in the number of family care-givers as a result of youths` migration to cities in search of white-collar jobs, and inability of government to provide adequate infrastructural needs to these aged persons has resulted in a miss-match on the caring facilities in Nigeria. These have contributed to the problem of these aged persons, since neither families nor government are able to meet their needs, especially in Africa due to high level of mass poverty, illiteracy and corruption in governance. Therefore, the task of this proposed system here is to design and model a voice activated home control system that will utilize the natural voice of the aged home occupants, to provide a more convenient, easier to install and use, user friendly home technologies for the aged persons. This will enable them maneuver assistive wheelchair, and manage home appliances through voice commands. This assistive wheelchair developed is embedded with collision detection and avoidance. The tools used to realize this proposed system are; The Personal Computer (PC), HC-SR04 ultrasonic sensor, and Voice Recognition (VR) module in a PC used for voice processing and recognition, Microphone for voice signal acquisition, C-language with the help of C# for coding. Bluetooth and Radio Frequency (RF) transceivers wirelessly link the input module to the controller module (microcontroller) which selects the appliances/assistive device to be controlled according to the input voice command. Proteus Virtual System Modelling (VSM) was used for developing smart home technology system schematic model and carried out the animated simulation to validate the system`s performance within the home. The designed system was tested on Dead Home (a home with closed curtains, carpet, an air-conditioner, and other leaving home appliances switched off) and Live Home (a home with opened curtains, carpet, an air-conditioner, television, and other leaving home appliances, switched on, and with background music or noise from a stereo people) conditions, and the effective result was 92.93% for dead home and 75.85% for live home respectively. This showed that the realized system controlled the devices with voice, though, the level of this system response is higher in dead home than in a live home, hence, the level of the system performance is lower in a noisy environment.Item Open Access Detection and prevention of amorphous cyber-attacks in process control networks of oil and gas installations(Federal University of Technlogy, Owerri, 2023-09) Obonna, Ugochukwu OnyekachiAmorphous cyber-attacks in process control networks (PCN) of oil and gas installations have posed a major cyber security challenge to the industry, due to the consistent deployment of unpredictable dynamic attack strategies by the attackers, which has made it difficult to predict their next attack modes. The aim of this dissertation is to monitor, detect, prevent and mitigate the effect of these malicious attacks on PCN. To achieve this, standard engineering structured methods, tools and techniques were applied by developing and analyzing mathematical models of the attacks, designing secured, centralized and distributed process control network architecture, designing a defense system capable of detecting false data injection attacks. The engineering materials, principles and concepts applied in the simulation, testing and validation of the developed models include: top-down structural approach, block diagrams, Machine learning algorithms, Deep learning toolkits, structured programming languages and simulation packages, such as: Python 3.0 Libraries, MATLAB, Allen Bradley PLC RSLogix 5000 emulator software, flowcharts and algorithmic representations of normal as well as compromised plant operations. Modelling and simulation of a 3-phase separator under attack was used to showcase attacks on PCN, predictions and forecasting using different machine learning algorithms. Real-time 68,722 SCADA dataset used in this research helped to overcome some of the shortfalls of previous researchers who used identical and repeated datasets that affected the learning ability of their algorithms and their final outcome. Several other machine learning algorithms and analytical tools were explored using the same dataset, but the Coarse Tree algorithm produced the best results with 100% accuracy, zero False Alarm Rate, one million observations per second prediction speed and 0.45488 seconds computation time. The results obtained showed the quality and precision of attack detections, hence the model’s robust performance in detecting network intrusions. The various units and system's tests conducted showed highly improved results of about 95% comparatively with previous industry research results, thereby confirming the probability of useful contributions made in ameliorating theft in Oil and Gas sector of the economy. The successful integration of the developed models to the developed PCN architecture, shows that the cyber-attacks vulnerabilities on Oil and Gas infrastructures could be detected, prevented and reduced to barest minimum, thereby preventing production downtime, with adverse impact on the economy of the country, in general.Item Open Access Characterization of multiple log-periodic array antennas for surveillance systems using a novel array-factor(Federal University of Technlogy, Owerri, 2023-11) Okoye, Arinze ChristianThis research endeavors to comprehensively characterize Multiple Log-Periodic Array (MLPA) antennas, specifically in the context of surveillance systems, using a novel array factor. This array factor streamlines the numerical characterization of MLPA antennas, regardless of the number of elements involved. The study employs a rigorous analytical approach, incorporating the Magnetic Vector Potential (MVP) model and pattern multiplication approach through a top-down methodology. The MVP model was chosen for its auxiliary function, which greatly simplifies the analytical processes. In practical terms, experimental Multiple Log Periodic Array antennas were designed and evaluated for this study. The parameters of these antennas were numerically assessed in the far field using the newly developed Array Factor. MatLab R2010a software played a pivotal role in simulating various parameters of the Multiple Log-Periodic Array antennas, including Array Antenna patterns, Electric/Magnetic fields, Average Poynting Vector, Radiation Intensity, Radiated Power, Directivity, and Directive Gain. The results demonstrated that the array antennas had a Directivity/Gain of 15.68dB or 45.68dBm, at the operating frequency range of 1.350GHz to 2.690GHz. The collective array patterns generated by the MLPA antennas were in line with expectations, relying on the corresponding field of single element. Multiple Log-Periodic Array antennas expanded the function of Single Log-Periodic Array (SLPA) antennas by significantly enhancing radiation gain and signal coverage. Thus, the novel Array Factor accelerates the process of characterizing array antenna parameters, thereby alleviating the bottleneck in computing antenna losses. This marks a significant advancement in the field of antenna technology.Item Open Access Utilization of musa paradisiaca leaf extract-based inhibitor for corrosion protection of carbon steel in 3.5% Nacl(Federal University of Technology, Owerri, Nigeria, 2025-05) Idema, Osuani FynefaceThe utilization of musa paradisiaca leaves (MPL) extract-based inhibitor on carbon steel protection in marine environment has been studied using gas chromatography mass spectroscopy (GC-MS), Fourier transform infrared spectroscopy (FT-IR), gravimetric method (GM), Atomic force microscopy (AFM), Contact angle measurement (Ө), potentiondynamic polarization (PDP), electrochemical impedance spectroscopy (EIS), density functional theory (DFT) and molecular dynamics (MD) simulations. Firstly, the GCMS analysis showed the presence of compounds with heteroatoms in the MPL inhibitor. Likewise, the FT-IR analysis showed the presence of polar functional groups. The GM showed MPL extract-based inhibitor having optimum inhibition efficiency of 91% at a concentration of 100g/L and immersion time of 120 hours which led to a decrease in corrosion rate from 0.8817 mm/y to 0.0823 mm/y. Also, the weight loss experienced by the test specimen decreased from 0.0986g to 0.0091g. AFM morphology revealed thin film adhesion showing firm adsorption of Langmuir films on the metal/inhibitor interface, with root mean square roughness values for uninhibited and inhibited substrates 71.2722Rq and 33.6773Rq respectively. Likewise, contact angle measurement showed high contact angle of 152.42●with a hydrophobic metal/inhibitor interface for inhibited substrate hence not prone to corrosive species and low contact angle of 76.20● for the uninhibited substrate with hydrophilic surface which is prone to invasive corrosive species. The potentiodynamic polarization (PDP) via Tafel plots showed a cathodic slope capable of controlling both activation (oxidation) and diffusion (oxygen reduction) reactions. Also EIS via Nyquist, Bode plots and Phase angle showing high polarization resistance thereby reducing corrosion rate. Further, Density functional theory (DFT) analysis correlated the results by affirming the contributions of the isolated compounds of the MPL inhibitor molecule to the inhibition efficiency of 91%. In addition, MD results showed planer orientation of MPL inhibitor molecules over the surface of the substrate as such enhancing larger surface coverage, hence better inhibition effectiveness. Also, the high adsorption energy of -184.954cal/kJ is indicative of chemisorption. Radial distribution function (RDF) showed presence of short bond lengths of between 2.97-3.49 atom thick, confirming the presence of strong covalent bonding. Test of adsorption isotherms reveal conformance of the Langmuir modelItem Open Access Environmental air pollutants as risk factors in the occurrence of respiratory conditions in some selected LGAs of Bayelsa State Senatorial Zones(Federal University of Technology, Owerri, 2025-05) Ekiyor, Christopher PeresAmbient (outdoor) air pollution is a major cause of disease and death globally. Poor ambient air quality occurs when pollutants reach high enough concentrations to affect human health and the environment. Long-term exposure to air pollution reduces life expectancy, as an after effect of respiratory diseases such as lung cancer which is associated with exposure to air pollution. The present study was primarily aimed at establishing the level of risk of respiratory conditions that are contributed by the various environmental air pollutants which affect the residents of Bayelsa State. The study was designed as a population-based survey study performed in Bayelsa State Nigeria. The study involved measurement of some targeted air pollutants and their ambient concentrations which were compared with the WHO‘s permissible standards and the Federal Ministry of Environment recommended limit. In addition, a questionnaire was used to assess 428 adult residents of Bayelsa State on the level of knowledge of the respondents about respiratory conditions, specifically on causes, prevention and control. The respondents were recruited from several communities across different local government areas in two senatorial zones in the State representing (Bayelsa Central and Bayelsa West). The two zones were purposively selected to represent the two types of environments in Bayelsa State (fresh water and salt water activities). Further, purposive sampling technique was also used to purposively select LGAs the fall within the fresh water and salt water activities in each of the two study zones. The mean ambient air quality level of the study area was compared with the WHO permissible limit and also with Ministry of Environment recommended standard for each pollutant using t-test method. Also, t-test was used to compare the mean ambient air quality level between Bayelsa West and Bayelsa Central while ANOVA test was used to compare the mean ambient air quality level across the study LGAs, The respiratory condition of the study participants was measured using PEFR and the outcome was classified as normal or poor respiratory conditions. The relationship between exposure to air pollutants and respiratory conditions were assessed in a logistic regression method. The result shows that the knowledge was high on some of the common respiratory symptoms such as persistent cough (93.3%), wheezing (92.8%) and Fatigue and weakness (72.7%). Just 53.7% (230 out of 428), showed good knowledge of respiratory conditions rom ambient air pollutants within their environment. The mean ambient level was high and exceeded WHO and FMOEnv permissible limit for all the pollutants SO2 (78.53 ± 22.32 μg/m3), NO2, (62.59 ± 17.78), C0 (8.47 ± 4.66), NH (0.37 ± 0.23), PM 2.5 (51.58 ± 17.17) and PM 10 (170.19 ± 44.42).Southern Ijaw contained the highest level of SO2 and NH (0.94μg/m3), The NO2 was found highest in Yenagoa (152.1 μg/m3), while CO also high in Ekeremor LGA (23.4μg/m3). The average PEFR was 451.6 ± 77.6 l/min for the study group. The mean PEFR was significantly lower in Bayelsa West (429.8 ± 73.4 l/min) than in Bayelsa Central (473.3 ± 87.5 l/min) (p < 0.0001). Common respiratory symptoms in the area were wheezing (25.7%), pneumonia (18.1%), 54 (11.6% for asthma (11.6%), COPD (11%), bronchitis (5.1%) and others. Association was found between exposure to air pollution and poor respiratory conditions (P <0.000). The study concluded that the study area is well polluted and required urgent attention to enforcement of protective measures against ambient air pollutants.Item Open Access Isolation, characterization and radical-scavenging potentials of bioactive components of combretum dolichopentalum leaves(Federal University of Technology, Owerri, 2016-04) Ujowundu, Favour NtiteThe present study isolated, identified and characterized the bioactive components of Combretum dolichopentalum leaves and determined the antioxidant potentials of the extracts of the leaves on some biochemical and physiological parameters. Biochemical methods such as ion exchange chromatography, column chromatography, thin layer chromatography, gas chromatography (GC), gas chromatography-mass spectrometry (GC-MS), spectrophotometric analyses, atomic absorption spectrometry and Fourier transform infra red (IR) were used. Preliminary phytochemical analyses showed the presence of flavonoids, alkaloids, saponins, tannins, oxalate and phytate. Further screening show the presence of flavonoids: kaempferol, luteolin, isorhamnetin and apigenin; alkaloids: akuamidine, undulantine, powelline and their hydroxylated compounds, voacangine and buphranidine; saponins: hicogenin, sapogenin, tribuloin and tannic acids. The use of GC-MS aided the identification of organic acids: (heptedecanoic acid), organic esters (ethyl octadecanoate), ketones (6,10-dimethyl-2- undecanone), alcohols (3,7,11,15-tetramethyl-2-hexadecen-1-ol) and phenol derivatives (Phenol-2,6-bis (1,1-dimethyl)-4 -methyl, methyl carbamate). Also, the eluates obtained from column and thin layer chromatography were analysed with IR and phenol-2,6-bis (1,1- dimethyl)-4-methyl, methyl carbamate, nitrocyclohexane, fluorodecane and others were identified. Proximate analysis showed the presence of carbohydrates, proteins, lipids, sodium, potassium, phosphorus, vitamins A, E and B-vitamins. Amino acid profile using the technicon sequential multi-sample amino acid analyser (TSM) showed the presence of essential and non essential amino acids. The effects of isolates such as flavonoids, saponins, alkaloids and tannins were determined for in vitro hydrogen peroxide scavenging ability. The effects of the extract in comparison with a standard drug (silymarin) on animal organ/tissue functions and on serum concentrations of electrolytes, beneficial transition minerals, lipids, antioxidants and markers of lipid peroxidation were determined. The effects of the crude extract in comparison with standard plant antioxidant (quercetin) and butylated hydroxyl toluene (BHT), for in vitro scavenging potentials showed dose dependent scavenging potentials on nitric oxide, hydroxyl radical, H2O2 induced lipid peroxidation and reducing power. Intoxication with CCl4 after pre-treatment with the ethanol extract and crude flavonoid, saponin, alkaloid and tannin fractions indicated hepatoprotective and antinephrotoxic potentials except saponins isolate which showed a significant (P˂0.05) adverse effect as indicated by some biochemical and physiological parameters. Flavonoid and alkaloid extracts are the major fractions that elicited biochemical and physiological benefits in CCl4 intoxication. The in vitro and in vivo radical scavenging properties of extracts of C. dolichopentalum make a promising drug with strong antioxidant potentials and inhibitory against Escherichia coli and Salmonella typhi.The present study isolated and characterized the phytochemicals in C. dolichopentalum leaves which could be further exploited for the treatment of oxidative stress and microbial induced disorders and diseases especially in lightItem Open Access Effects of some indigenous plant extracts on carbon tetrachloride-induced hepatic fibrosis in male wistar rats(Federal University of Technology, Owerri, 2017-11) Ukairo, Doris IfeyinwaPlant-derived drugs and antioxidants are widely used in the management of chronic liver diseases and cirrhosis. Methanol extracts of raw (R) and cooked (C) samples of Sphenostylis stenocarpa (SS), Chromolaena odorata (CO), Buccholzia coriacea (BC) and Monodora myristica (MM), at doses of 250 mg and 500 mg per kilogram body weight of male Wistar rats were evaluated for their effects on carbon tetrachloride (CCl4)-induced hepatic fibrosis. One hundred and sixty (160) rats (155 ± 20 g) were distributed into twenty groups of eight rats each; representing normal control, olive oil control, negative control, positive control (silymarin) and various groups treated with raw and cooked extracts of the samples at the stated doses (RSS250, RSS500, CSS250, CSS500, RCO250, CCO250, etc.). The extract-treated groups were pre-treated with their respective extracts twice a week for four weeks before the introduction of toxicant. All the groups except normal and olive oil controls were intraperitoneally injected with 1 mg/kg of CCl4/olive oil (1:1 v/v) mixture twice a week for four weeks with continued extract-treatment. Liver and kidney damage were assessed using various biochemical parameters, such as the enzymes; alanine aminotransferase (ALT), aspartate aminotransferase (AST), alkaline phospatase (ALP), lactate dehydrogenase (LDH) activities, as well as bilirubin, urea, creatinine, electrolytes and malondialdehyde (MDA) concentrations. In addition, CCl4-induced pathological changes were evaluated by histopathological studies and the expression of collagen as evidence of induced fibrosis confirmed by immunohistochemistry. Treatment with methanol extracts of SS, BC and MM especially at low concentrations significantly (P<0.05) ameliorated the effects of CCl4 intoxication by reducing hepatic enzymes and LDH activities and as well increased other parameters. The effects of the extracts were attributed to the phytochemical compositions of the plants. The findings provided evidence to show that methanol extracts of SS, BC and MM at low concentrations possessed antifibrotic and hepatoprotective properties against CCl4-induced liver injury in male Wistar rats through their antioxidant and anti-inflammatory activities.Item Open Access Physico-mechanical properties of natural rubber filled with treated groundnut shell powder for shoe sole production(Federal University of Technology, Owerri, 2016-03) Ayo, Mark DadaPhysico-Mechanical properties of natural rubber filled with chemically modified groundnut shells were studied. Natural rubber composites were prepared using modified fillers at varying concentrations of sodium hydroxide (NaOH) Solution and acetylating solutions respectively. The processing conditions, mechanical properties and sorption characteristics of these composites were analyzed. The cure characteristics of the compounded rubber were determined using Mosanto Rheometer (model MDR - 2000). The maximum torque and crosslinking density increases with increase in concentration of the mercerizing and acetylating agent. The fibre reinforcing efficiency of the chemically treated composites were compared with that of the untreated composite. Composites containing chemically treated fillers were found to posses improved tensile properties(from 18.30 to 31.50MPa for acetylated composites and 18.30 -28.00MPa for mercerized fillers), hardness (48 to 65 IRHD for acetylated filler and 48 to 58 for mercerized fillers) and abrasion resistance (from 31.55 t0 42.50% for acetylated filler and 31.5 to 39.30 for mercerized filler). These properties increases with increase in mercerizing and acetylating agent up to 20% concentration and starts decreasing. At higher concentration, the fibre is destroyed hence reduction in properties. These results were in agreement with empirical analysis. The sorption properties of the composite also decrease with the concentration of the mercerizing and acetylating agent. The improved properties observed were as a result of the increase in affinity between the rubber matrix and the chemically treated groundnut shell fillers. From this research work, it is recommended that chemically treated groundnut shell powder, particularly at 20% concentration can be employed for articles such as shoe soles, footmats and hoses that require less stress during service life.Item Open Access Production and characterisation of biodegradable biofilm from plantain peel, eggshell and cassava starch(Federal University of Technology, Owerri, 2025-01) Okeyahweh, Chinyere SimchaBiodegradable films are made from natural polymeric materials such as starch, vegetable oil, cellulose, lignin, and also materials derived from animals such as proteins and lipids. They are easily degraded by microbes, and the degradation process does not take a long time. The present study investigated the use of ripe plantain peels as a source material for producing biodegradable biofilms; using powdered ripe plantain peels, eggshell powder, acetic acid – vinegar - and cassava starch produced in the study. The biofilms synthesized were plantain peel-based biodegradable biofilms: P-BF, and non-plantain peel biofilm: N-BF, which served as control. The synthesized biofilms were characterized using FTIR, GC-MS, morphology test, water absorption property, biodegradation test, solubility test and swelling test and mechanical test; ultimate tensile test, flexural, hardness test, % elongation and thermo gravimetric analysis. The results of the FTIR analysis of the P-BF and N-BF showed 8 functional groups: ether, ethene, amine, carboxylic acid, nitriles, methylene, cyclic ester, primary, secondary and tertiary alcohols common to hydrocarbons. The results of the biodegradability test showed that both P-BF and NBF biofilms degraded completely on the 12th day. The results of the thermo gravimetric analysis showed that the P-BF biofilm decomposed at the temperature of 29.920C-500°C leaving 44.19% residue and compared to the N-BF biofilm which decomposed at the temperature of 22.170C - 500°C leaving 11.9% residue. This implies that, P-BF matrices, started degrading at 130 °C, while N-PF fibers start degrading at 139 °C. Therefore, the processing temperature for ripe plantain peels was set to below 137 °C to avoid unwanted degradation of the material. Furthermore, the results of the mechanical tests for P-BF showed ultimate tensile test, flexural test, hardness test, and % elongation; 2.87±0.02 Nmm^2, 0.41±0.01 Nmm^2, 22.00±1.78 Nmm^2 and 6.29±0.01 Nmm^2 respectively. while, the result of the mechanical test of N-BF showed ultimate tensile test, flexural test, hardness test and % elongation; 5.45±0.02 Nmm^2, 0.41±0.01 Nmm^2, 49.00±1.78 Nmm^2 and 13.85±0.03 Nmm^2 respectively. The solubility test of P-BF showed partial solubility in acetone, sulfuric acid and ethyl alcohol while the N-BF were completely insoluble in ethyl alcohol but partially soluble in sulfuric acid and acetone. The result showed that the biofilm was not completely soluble. The results of the swelling test for P-BF showed a mean of 0.04±0.00 when soaked in chloroform; and N-BF; 0.02±0.00. When soaked in methanol, P-BF showed a mean of 0.10±0.00 while N-BF showed a mean of 0.10± 0.01.The water absorption analysis showed that P-BF had 31% engorgement while N-PF had 46 % engorgement. The P-BF have high affinity for water due to the hydrophilic nature of the cellulosic fibers in the plantain peel as well as the water absorbing property of glycerol. The biodegradability test showed the plantain based biofilm degraded completely with no toxic effect on the soil implying that the biomass may serve as a potential material for production of an ecofriendly biofilm with good mechanical properties. The study showed that biodegradable biofilms can be synthesized from plantain peel at 3 % plantain peel, 1 % acetic acid, 3 % cassava starch, 1 % eggshell and 3 % glycerol. In conclusion, the study reported that powdered plantain peel-based biofilm with good mechanical properties can be produced.Item Open Access Impacts of anthropogenic activities on soil and water quality of Kolo-Creek, Niger Delta, Nigeria(Federal University of Technology, Owerri, 2024-11) Ajayi, OlumideThis study evaluates the impact of anthropogenic activities on soil and water resources in Kolo Creek, Niger Delta, Nigeria. Hydrocarbon exploration, illegal refining, and waste disposal have significantly disrupted environmental balance, necessitating site-specific assessments and pollution evaluation for effective mitigation. Soil, surface water, and groundwater samples were collected from ten georeferenced locations, with groundwater extracted from six meters’ depth. Heavy metals (Fe²⁺, Pb²⁺, Cd²⁺, Cr³⁺, Cu²⁺, Zn²⁺) were analyzed using atomic absorption spectrophotometry (AAS), while total petroleum hydrocarbons (TPH), polycyclic aromatic hydrocarbons (PAH), and benzene, toluene, ethylbenzene, and xylene (BTEX) were measured via gas chromatography-flame ionization detection (GC-FID). Geotechnical properties (Atterberg limits, porosity, permeability) were assessed per ASTM (1975) and British Standards (BS 1377). Results indicate that apart from low pH (acidic conditions), most surface and groundwater parameters comply with WHO drinking water standards, except Fe²⁺ (125.82 mg/L), Hg²⁺ (1.05 mg/L), TPH, PAH, and BTEX, which exceed permissible limits. Multivariate statistical analysis identified six (6) principal components, while hierarchical cluster analysis (HCA) revealed two distinct pollution sources. Correlation analysis confirmed strong interrelations among contaminants, implying a common pollution origin for soil, surface water, and groundwater. Contamination factor analysis classifies Fe²⁺ (9.1) as highly contaminated in surface water, while Ca²⁺ (2.88) and Fe²⁺ (125.82) in groundwater indicate moderate to extreme contamination. Water quality index (WQI) results confirm that 100% of water samples are unfit for drinking, irrigation, or industrial use. Additionally, pollution index of groundwater (PIG >2.5) suggests severe contamination. However, irrigation suitability tests indicate that surface water meets agricultural standards based on Sodium Absorption Ratio (SAR) values. Heavy metal contamination in soil, particularly Fe²⁺ (18.97), Al³⁺ (1.02), Hg²⁺ (1.05), and Cd²⁺ (1.28), poses significant environmental risks. Geo-accumulation index (Igeo) classifies soil as moderately polluted by Cd²⁺ and heavily polluted by Fe²⁺ and Hg²⁺. Furthermore, carcinogenic risk (CR) assessment shows that average CR values exceed 10⁻⁶ (>10⁻⁶) for both adults and children, indicating a potential cancer risk. Alarmingly, children face a threefold higher cancer risk than adults. Hydrocarbon contamination has altered soil geotechnical properties, evidenced by lower permeability and plasticity index (5–9%), classifying it as low-plastic, partially cohesive silt. However, this modification suggests that affected soils could be reused for engineering applications.Item Open Access Modelling of combustion in natural draft burners for improved performance(Federal University of Technology, Owerri, 2024-02) Nwoye, Favour ChukwunonsoCombustion in natural draft burners involves the passive induction of atmospheric air into the burner mixer when a fuel jet flows through a venturi. The interaction of the fuel jet and air stream at different velocities causes shear and Kelvin Helmholtz instability that grows into turbulence and molecular mixing of both species. Modeling of flow and combustion process in natural draft burners for improved performance are presented. It involves the response of the flow to changes in the axial coordinate of the nozzle and passive alteration of the flow conditions upstream of the origin. The alteration was by varying the nozzle streamlines and installing a trip ring at the nozzle exit. The Reynolds Averaged Navier-Stokes (RANS) equation was used to model the flow physics; the turbulence modelling was done with the Reynolds Stress Model (RSM), while the standard wall function captured the near wall flow behaviour. The implementation was undertaken using ANSYS Fluent 18.1, and the model was validated with Binder and Kian experimental work. A low-fidelity model developed and implemented with a MATLAB script offered a cheap and quick alternative for the parametric investigation of jet flow and combustion processes. The flow parameters of interest are the velocity decay, pressure gradient, turbulence, ambient air entrainment, and its mixing with the fuel jet stream. The ratio of the axial distance between the nozzle exit and throat 𝑙𝑇𝑁 and the throat diameter 𝑑𝑇, 𝑙𝑇𝑁 𝑑𝑇 defined the position of the nozzle from the throat. At 𝑙𝑇𝑁 𝑑𝑇=2.0 and 𝑙𝑇𝑁 𝑑𝑇 = 0.5 as reference, the increase in the velocity decay rate and the entrainment values were over 8% and 7%, respectively. These shows that when the nozzle was closer to the air inlet, velocity decay was faster, the entrainment was higher, and the mixing was better. The modification with the trip ring involved the installation of 0.5mm thick rings at the nozzle exit. The installed ring diameters were 4.9, 4.7, and 4.5mm, concentric with the nozzle trailing edge. The wake formed behind the trip ring interacted with the streamwise vortices and suppressed the near-stream turbulence. Flow modification with a 4.9mm ring increased the turbulence at the ejector outlet by over 26.6%. The final entrainment value was 16.7% higher, but the drop in the decay rate was 9.6%. The 4.9mm ring performed best because of the delayed flow separation and reduced pressure drag. Four different nozzle streamlines (PN1, PN2, PN3, and PN4) produced by straight lines and sine function combinations yielded different streamwise sectional area. With PN4 as the reference nozzle, the decay rate, entrainment and the maximum turbulence intensity increased by approximately 1.7, 8 𝑎𝑛𝑑 16%, respectively, in the PN3 nozzle, which has the smallest streamwise sectional area and the highest momentum difference between the streams. The relationship between the near stream decay rate and the streamwise sectional area was linear. Therefore, passive modification of the jet structure improved the burner performance substantially. Pressure drag formed behind the ring adversely affected performance. An optimized streamlined ring profile can delay flow separation and reduce pressure drag, thus recommended for further investigationItem Open Access Development and performance evaluation of a diurnal passive radiative cooling system for application in buildings(Federal University of Technology, Owerri, 2024-02) Okoro, Humphery OgbonniaSpace cooling for thermal comfort consumes significant amount of energy, and this has continued to be a major global challenge. However, space cooling needs are increasing in the tropics due to increase in energy intensive lifestyles, population increases, and incessant increases in ambient temperature. Global warming and climate change issues associated with convectional energy usage are increasingly informing investments in sustainable and clean energy systems. Accordingly, the development and performance evaluation of a diurnal passive radiative cooling system for space cooling application in buildings are hereby presented. Two diurnal passive radiative coolers using dual-layer mesoporous polyethylene aerogel and ultra-white barium sulphate on silver substrates as selective reflective surfaces were designed and fabricated. This test rig is a rectangular box with two compartments in which the coolers are installed for investigation. The top of the test rig is covered with a low density polyethylene windscreen, which is transparent to radiation in all wavelengths. Thermocouples are inserted underneath and outside the coolers to record the temperatures of the coolers and the ambient respectively. Extensive field investigations were conducted with these photonic coolers under direct solar irradiance in three different locations under Nigerian climatic conditions, namely, Abuja, Afikpo, and Owerri. The experimental results for a 24- hour test show that the diurnal passive radiative system achieved significant cooling performances with sub-ambient temperatures of about 3-5, 3-6, and 2-6 oC during the daytime and 1-2, 0-1, and 0.5-2 oC at night, for Abuja, Afikpo, and Owerri respectively for Mesoporous polyethylene aerogel cooler. For the barium sulphate cooler, sub-ambient temperatures of 2-3, 1.5-3.5, and 1-3.5oC during the daytime and 0-1.5, 0-0.5, and 0-1 oC at night were reported. Average cooling powers of 108.84, 84.99, and 101.06W/m2 were recorded in Abuja, Afikpo, and Owerri respectively with the mesoporous polyethylene Aerogel, while 120.29, 89.81, and 106.74W/m2 were recorded with the barium sulphate in Abuja, Afikpo, and Owerri, respectively, during the investigation. Also, a theoretical model was developed and used to numerically predict the thermal performances of the coolers in six locations, namely, Abuja, Yola, Afikpo, Ado-Ekiti, Kaduna, Owerri, and Warri, representing the different geopolitical zones in Nigeria. The model equations were discretized using finite element numerical scheme for ease of implementation on a digital computer. The system behaviour was simulated with the developed model using a code written with FlexPDE Finite Element Model Builder and Numerical Solver Version 7.12. The numerical results obtained from the models were compared with experimental results and other similar data from the literature. The deviations of the model and experimental temperatures were recorded as ±2.73oC for Mesoporous polyethylene aerogel and ±1.81oC for barium sulphate. Thus, for the numerical performance evaluation, the model results closely matched experimental results with total standard uncertainties of 0.64 for Mesoporous polyethylene aerogel and 0.37 for barium sulphate. These deviations are less than 1, which is a necessary condition for model accuracy. Sensitivity analyses show that the optimal performance parameters are 15mm, 30o , and 5, for the cooler thickness, orientation and number of windscreens, respectively. Therefore, further material development, extended field investigation, and possible deployment of passive radiative cooling system for use in residential buildings are recommended.Item Open Access Optimization of biogas production from some agrowastes in a batch system bioreactor(Federal University of Technology, Owerri, 2023-12) Nwaneri, Chioma BlessingThis study was carried out to co-digest and optimize biogas production from some agrowastes in a batch system bioreactor. Six substrates; Palm oil mill effluent (POME), Pig dung, Cow dung, Poultry manure, Cassava peels, and Cabbage waste were used in the investigation. The proximate analysis of each substrate and the microbiological analysis of the co-digested subsrates were obtained. The substrates were anaerobically digested as single substrate and codigested with each other to improve the nutritional composition and biodegradability. Laboratory scale 10L capacity bioreactors were used to carry out the batch system anaerobic digestion of the different substrates for substrate ratios of 1:1, 2:1, 3:1, pH range of 6.8-8.0 and a hydraulic retention time of 45days. Then Box Behnken’s design of response surface methodology of three factors; substrate ratio, pH, and hydraulic retention time at three levels; 1:1, 2:1, 3:1(substrate ratios), 5, 7, 9 (pH) and 15days, 30days and 45days (hydraulic retention time) were used in the optimization, considering the substrate with the highest biogas yield.Sodium hydroxide (NaOH) and hydrochloric acid (HCl) were used for adjusting the pH values to the required range. Compositional gas analysis of biogas produced was carried out using Gas Chromatography. The proximate analysis of the substrates showed that the C:N ratios of POME, pig dung, cow dung, poultry manure, cassava peels and cabbage waste were 10.13:1, 5.84:1, 17.50:1, 14.24:1, 46:1 and 16.90:1 respectively. It was also observed that none of the substrates had an optimium C: N ratio hence there was need for co-digestion of the substrates to improve biogas yield. The result also showed that co-digestion of cassava peels with cow dung had the highest biogas yield, flamed on the second day with bright blue flame and had the highest percentage methane content of 78.05%. The results showed the presence of these bacterial isolates; Escherichia coli, Enterobacter sp, Salmonella sp, Shigella sp, Bacillus sp, Pseudomonas sp, Staphylococcus sp, Micrococcus sp and fungal isolates were Saccharomyces sp, Aspergillus sp, Rhizopus sp, Penicillium sp, Geotrichum sp. The optimization result showed that the substrate ratio of 3:1, pH 7 and 15days hydraulic retention time had the highest biogas yield, highest methane content of 79.143% and flamed on the second day of the anaerobic digestion. Statistical analysis of the results showed significant difference (p ≤ 0.05) in biogas production in all the treatments. Further anaerobic digestion of cassava peels with cow dung using the predicted values from the computer aided Box Behnken design response surface methodology analysis showed the same trend with the experimental data. In terms of sustainable biogas production, the outstanding result showed by CP/CD 3:1 at pH 7 proves that the test parameter can be adopted for domestic biogas production.Item Open Access Tree species diversity, biomass production and carbon stock of three forest management types in Benue State, Nigeria(Federal University of Technology, Owerri, 2025) Dau, Henry JaphethCarbon stocks can be conserved or increased by the sustainable management of existing forest types. However, anthropogenic activities and poor forest management can adversely affect biomass production and carbon storage. Published information on biomass and carbon storage potentials of different forest management types is scanty, especially in the study area. To this end, this study assessed the tree species diversity, soil properties, volume estimation, biomass and carbon storage of three forest management types (Community Forest Area (CFA), Forest Reserve (FR), and Sacred Grove (SG)) in Benue State, Nigeria. A nested plot design was adopted for data collection. Each nested plot comprises 35 m x 35 m, 25 m x 25 m, 7 m x 7 m, and 1 m x 1 m square plots. The 35 m x 35 m area was the main plot within which all trees with a Dbh of 40 cm and above were measured. The 25 m x 25 m subplot was laid within the main plot, and all trees with Dbh between 20 cm and 40 cm were measured. Within each subplot, a sub-subplot of 7 m x 7 m was laid for the enumeration of trees with a Dbh range of 5 m to 20 cm. A quadrat of 2 m x 2m was laid within the 7 x 7 m plots to assess low vegetation with a diameter <5 cm. A square frame of 1 m x 1m was laid to assess all litter. An experienced forest-type management taxonomist identified all live tree species. Tree growth variables (diameters at the base, breast height, middle, and top of the tree and tree total heights) were measured on all live trees, standing dead and lying dead trees in all plots. An indirect method of biomass estimation was used in this study. Tree core samples were collected at tree breast height (1.3m) using an increment borer. Data were analyzed using descriptive (mean, frequencies, and standard deviations) and inferential (analysis of variance, T-test and Pearson correlation) statistics. A cumulative total of 1,881 individual trees were enumerated in the study area, with 749, 621, and 511 individual trees found under FR, SG, and CFA, respectively. A total of 73 tree species in 35 families were assessed in the study area, out of which CFA had 38 species from 25 families, FR had 28 species from 16 families, and SG had 35 species from 24 families. Most of the tree species were indigenous, with few exotic species (Gmelina arborea and Tectona grandis). Khaya senegalensis and Gmelina arborea were present across the three forest management types, with varied frequency of occurrence. The Family Importance Value Index (FIV) in CFA and SG indicated higher family density in these forest management types than in FR. A few families (Caesalpinioideae, Euphorbiaceae, Moraceae, and Fabaceae) were important across the forest management types. Malvaceae, Verbenaceae and Fabaceae were the most important families in CFA, FR and SG, respectively. Ty. The Shannon-Wiener index of 3.00, 2.11 and 2.97 were recorded under CFA, SG and FR, respectively and differed significantly. The Margalef richness index was highest (6.01) under CFA and lowest (4.11) under the FR. The highest evenness value of 0.55 was recorded under SG, and the lowest value (0.29) was under FR, indicating a high disparity in tree species richness. Gmelina arborea, SterculiaItem Open Access Management of insect pests of bambara groundnut (Viga subterranean (L.) Verdcourt.) with some plant oils in rain forest zone of Owerri, Imo State(Federal University of Technology, Owerri, 2023-03) Nwamkpa, Akachukwu PiusStudies were conducted from March- June for the early season and August- November for the late season of 2016 and repeated same time in 2017 at the Postgraduate Teaching and Research Farm of the Department of Crop Science and Technology, Federal university of Technology, Owerri, Nigeria. A total of 60 treatment combinations were laid out in a 5 x 4 factorial arrangement with three replications fitted into a randomized complete block design (RCBD) for the field trials to evaluate the efficacy of the plant oils (Bush tea Hyptis suaveolens. (HEO), Stool wood Alstonia boonei. (AEO), Jathropha tanjorensis (JEO,) mixed plant oils from Jathropha, Bush tea and Stool wood bark (J+A+HEO) against field insect pests of Bambara groundnut. Population dynamics of insect pests of Bambara groundnut under control measures with plant oils were also studied. The oils were tested at four rates (0.00, 2.00, 4.00 and 6.00 ml/100 ml of H2O per plot) and Cypermethrin 10EC at the rates of (0.00, 0.20, 0.40 and 0.60 ml/100 ml of water per plot). Some field insect pests including variegated grasshopper (Zonocerus variegatus), Flea beetle (Podagrica uniformis and Podagrica sjostedti), Leaf miner (Aproaerima modicella) and Aphids (Aphids crassivora) inflicted damage to the leaves of Bambara groundnut. The treatment materials provided effective protection against insect pests of Bambara groundnut at different levels when compared to the unsprayed plots. The unsprayed plots recorded highest number of damaged leaves at the vegetative phase, flowering and podding phase followed by the lowest application rates, while the highest application rates recorded the least damaged leaves by insect pests in 2016 and 2017 early and late planting seasons. The results on yield showed that the plant oils were able to reduce the population of insects which resulted in an increase in the 100 Seed and Pod weight (g), Seed and Pod yield (kg/ha, though they were not significantly different (P>0.05).Item Open Access Analysis of response capacity of rural households to selected poverty intervention programmes in Imo State, Nigeria(Federal University of Technology, Owerri, 2016-11) Ajaero, Joseph OnyewuchiThis study analysed the response capacity of rural farmers to National Fadama Development Programme (NFDP) and National Special Programme for Food Security (NSPFS) in Imo State, Nigeria. The specific objectives were to; categorize and describe response capacity of rural farmers, assess the level of knowledge of rural farmers’ to the rural poverty intervention programmes, determine the relationship between behavioural process and response capacity, determine factors that affect positive response to rural poverty intervention programmes, ascertain the rural farmers’ perception of agricultural extension effectiveness on positive response to rural poverty intervention and identify the perceived constraints to desirable response to poverty intervention programmes in the study area. Data were collected through the use of standardized questionnaire. Descriptive statistics (frequency distribution, mean score and percentages) and inferential statistics (multinomial logit regression, Chi-square and Univariate analyses) were used to analyse the data generated. The mean age was 50.7 years. Majority (57.9%) of the rural households in the study area were male with mean household size of 6 persons. The results further showed that majority (86.5%) of the rural farmers were engaged in crop production. The mean net annual farm income was N97041.63. Majority (90.6%) were members of social organisation especially cooperative societies (65.1%). A total of 97.4 percent had one form of formal education or the other. Extension agents (71.7%) were identified as their major source of agricultural information. The study found that majority (58.3%) of the rural farmers had high level of knowledge about NFDP while only 31.7% had high knowledge level about NSPFS. Majority (64%) of the rural farmers perceived extension service as not effective in activities in rural poverty intervention programme. The study also revealed that behavioural process has a positive and significant effect on response capacity at p0.05 critical level with a regression coefficient of 0.693 and R 2 of 0.894. Majority (65.7%) of the rural farmers in the study area fell within the desirable response capacity, which is a sociological prerequisite for participation in rural poverty intervention programme. The multinomial logit regression results revealed that probability of being in the desirable response category increases with net annual income (4.055) and farmers’ self esteem (0.373) while sex (4.645), level of education (9.300), extension effectiveness (38.569), number of information sources (11.772) and distance to LGA headquarters (11.111) each decreases the probability of being in desirable response category to rural poverty intervention relative to the reference category. The constraints militating against positive response to NFDP and NSPFS poverty intervention programmes included institutional bottlenecks of the programmes (M = 3.32), lack of access to credit (3.19), lack of capital (M = 3.00), stringent requirements for qualification to participate in the programmes (M = 3.16), lack of awareness of NSPFS (M = 2.98) and lack of awareness of NFDP (M = 2.56). The study recommends that government should reposition extension service to be effective in services delivery to targeted beneficiaries in future poverty intervention programmes. Also the existing public agricultural extension service, Imo State Agricultural Development Programme (IMADP) should work in synergy with programme-donor agencies in order to carry out good sensitization campaigns at the inception of any rural poverty programme to create awareness and lay the foundation for desirable response required for the programme success.