Nnamdi Azikiwe University Journals
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Prediction of tensile strain in mild steel tig weld using artificial neural networks
No full textTensile strain is the relative length of deformation exhibited by a specimen subjected to a tensile force. An artificial neural network (ANN) was employed to predict the tensile strain of the weldment. One hundred welded specimens of mild steel, measuring 60mm x 40mm x10mm, were prepared and calculated using the VWACgauge. The results were employed to train ANN. The research produced an R2 of 86% in comparison to the experimental result on a fitted line plot using regression analysis, while correlation analysis obtained in the training and validation exercise from ANN was over 90%. Results of the study have shown that ANN is a robust predictive tool in welding, which could help reduce trial and error in welding processes
Electro Deposition of silver sulphide (Ag2S) and cerium doped silver sulphide (Ce: Ag2S) thin films for structural properties investigation
No full textIn this research, Ag2S and Cerium doped Ag2S thin film were successfully synthesized and characterized for structural properties analysis for optoelectronics devices application. Deposition of thin film made from cerium-doped silver chalcogenide (Ce:Ag2S) was conducted at room temperature. Crystal structural analysis of the deposited thin film was done using x – ray diffractometer machine. Various bath parameters including deposition time, pH level, and molar concentration of the cerium precursor were adjusted to optimize their impact on the structural characteristics of this thin film. The effects of percentage concentration of cerium dopant, deposition time and pH on the structural properties of Ag2S and Cerium doped Ag2S thin films were reported in this work. From the experimental investigation, increase in intensity of the diffraction spectra was observed as dopant concentration increased from 5% to 10%. The diffractogram exhibits distinct peaks corresponding to specific crystallographic planes, indicating changes in lattice parameters due to varying deposition times which shows that that longer deposition times lead to better crystal quality with fewer lattice defects and larger crystallites. The investigation also revealed that lowest pH tested leads to a good balance of structural properties. The obtained results in this study revealed good results which are comparable with results obtained by other researchers in literature. These results obtained suggest the possibility of using the material in optoelectronics devices like LEDs, solar cells, transducers, and photodetector
A cost-effective multi-objective optimization technique for automatic voltage regulator placement in radial distribution power network
No full textOptimizing distribution network operations has emerged as critical priority with a key focus on leveraging distribution system network enhancement to drive improvement in network performance. This study aims to determine the optimal placement of Automatic Voltage Regulators (AVRs) in radial distribution networks to achieve superior performance. A comparative analysis of conventional and non-conventional approaches revealed the efficacy of the Adaptive and Dynamic Inertia Weight acceleration Coefficient (ADIWACO) Particle Swarm Optimization (PSO) algorithm in optimizing AVR placement. Notably, the loss sensitivity factor and ADIWACO PSO variant achieved significant percentage error reductions of 50% and 51%, respectively. Furthermore, the ADIWACO variant demonstrated superior optimal searching capabilities, with a standard deviation error of 0.000426. Economic analysis validated the results, confirming that the real power loss reduction achieved through optimal AVR placement yields substantial economic benefit
Synthesis of clay, and iron oxide nanocomposites for the removal of anionic dye from aqueous media
No full textThis experimental investigation was conducted to study the synthesis of a clay/iron oxide nanocomposite for the removal of anionic dyes from aqueous media. Batch adsorptive performance tests at various temperatures were evaluated at the optimum conditions of the adsorption parameters for the Clay/Fe3O4 nanocomposite adsorbent of pH, initial dye concentration, temperature, adsorbent dosage, and contact time. From the batch adsorption study, the optimum percentage removal of the anionic RR 198 dye for the Clay/Fe3O4 nanocomposite was obtained at pH 6. The novelty of this study is seen in the unique properties and high removal efficiency of the clay nanocomposite, combined with an iron oxide nanocomposite, with both magnetic and catalytic properties necessary for wastewater purification. The adsorption kinetic data were analyzed using several kinetic models, namely, the pseudo-first-order, pseudo-second-order, and Elovich equations. It was established that the adsorption data fitted well for the pseudo-second-order kinetic model, while the Langmuir isotherm was the best fit for the isotherm models. The evaluation of thermodynamic parameters such as the free energy ∆Gº, enthalpy ∆Hº, and the change of entropy ∆Sº gave negative values, indicating a feasible, exothermic, and spontaneous nature of the reaction
Carbonate Facies and Depositional Environment of the Kalambaina Formation, Sokoto Basin, Northwestern Nigeria
No full textThe Kalambaina Formation, part of the Paleocene Sokoto Group in the Iullemmeden Basin, represents a critical stratigraphic unit for understanding shallow marine sedimentation in northwest Nigeria. This study aims to characterize the lithologic, stratigraphic, and petrographic features of the formation to infer its depositional environment and economic significance. Field investigations were conducted across four key localities to document lithologic successions, while thin-section petrography was performed to identify microfacies and matrix composition. Results reveal a consistent vertical sequence of phosphatic shale overlain by fossiliferous limestone at all localities, suggesting a marine transgressive system. At Locality 1, the basal phosphatic shale transitions sharply into a 1.2m fossiliferous limestone, indicating a rapid environmental shift. Locality 2 shows a gradational boundary between a 3.5m shale unit and a 3m limestone, indicative of continuous transgression. Thin-section analysis classifies the limestone as biomicrite and wackestone adapting Folk and Dunham’s classifications respectively. Micrite are micro crystalline carbonate having major or only rock component while wackestone are depositional textures that contains carbonate mud of greater than 10% grains. Fossil assemblages, including Elphidium Crispum and Endothyra, confirm deposition in low-energy intertidal to subtidal zones. The findings suggest that the Kalambaina Formation was deposited in a shallow marine carbonate platform influenced by periodic transgressive-regressive cycles. The phosphatic shales, with potential as hydrocarbon source rocks, and the porous fossiliferous limestones, indicative of reservoir potential, highlight the formation’s economic importance. Comparisons with analogous systems in the Tarim Basin and Zagros Foreland Basin reinforce its role in regional sedimentary processes. This study provides new insights into the stratigraphic and paleoenvironmental evolution of the Kalambaina Formation, offering a framework for future hydrocarbon exploration and geological research in the Iullemmeden Basin
Functional Properties of Composite Flours Produced From Blends of Fermented Maize (Zea mays L) And Fermented Soybean (Glycine max) Flour
No full textThe objective of this study was to determine the functional properties of composite flours produced from blends of fermented maize (Zea mays L) and fermented soybean (Glycine max) flour. Maize grains were sorted, cleaned, fermented for 48 h, oven dried (60 °C to constant weight), milled to flour and then sieved (250 μm) to produce maize flour. The soybean was sorted, cleaned, boiled, cooled, dehulled, and fermented for 48 h with Rhizopus oligosporus (0.4g per 100g of soybean), oven dried (60 °C to constant weight), milled and sieved (250 μm) to produce fermented soybean flour. Using mixture design, maize and soybean flour samples were blended in the ratios 90:10, 80:20, 70:30, 60:40, and 50:50 to obtain composite flours while 100% maize flour and 100% soybean flour served as controls. Functional properties of the samples were evaluated. Inclusion of fermented soybean to fermented maize flour significantly (p<0.05) increased bulk density, oil absorption capacity, swelling capacity, foaming capacity and pH while water absorption and emulsification capacities decreased. Flour sample with 90:10 – fermented maize:fermented soybean flour had the highest water absorption capacity (2.96g/mL) while flour sample with 60:40 – fermented maize:fermented soybean flour had the highest bulk density (14.67g/mL) and oil absorption capacity (4.45mL/g). These findings suggest that incorporating fermented soybean flour into fermented maize flour enhances its suitability for use in baked goods, emulsified foods, and thickening agents. It is recommended that fermented soybean inclusion levels of 40 -50% be used for baked products requiring higher bulk density and oil retention
Nutritional Assessment and Sensory Properties of Dried Pap Fortified with Soybean and Date Palm Fruit Flours
No full textThe nutritional inadequacy of exclusive breastfeeding becomes evident from six months onwards, highlighting the importance of introducing complementary foods to ensure optimal infant nutrition. This study evaluated the nutritional and sensory properties of dried pap fortified with soybean and date palm flours using face central Design. Maize grain was cleaned, washed, soaked in potable water for 72h, wet millet, sieved, dried in a cabinet dryer for 8h at 50 oC; the date palm fruit was washed deseeded, dehydrated at 50 oC for 30 min, ground and sieved with 1.19mm mesh. Soybean seed was washed soaked for 12h at 30 oC, dehulled, boiled for 2h at 80 oC, dried at 60 oC for 24h, milled and sieved using 600 µm mesh size. The moisture, ash, fat, protein, fibre and carbohydrate contents ranged from 6.20 – 7.06 %, 3.25 – 5.10%, 4.37 – 14.67%, 7.72 – 16.87 %, 12.49 – 21.97% and 35.22 – 65.48 %, respectively. Bulk density, swelling capacity and water absorption capacity ranged significantly from 0.07 – 0.79 g/c3, 0.845 – 1.060 g/g and 0.898 – 0.955 g/g respectively. The sensory attributes of the pap samples varied significantly in terms of colour, odour, flavor and overall acceptability. It was 5 g date flour plus 5 g soybean flour was the most preferred besides the control samples. The finding of this study suggest that dried pap fortified with soybean and date palm flours has the potential to improve the nutrients and sensory quality of the product
Microplastic Contamination: An Emerging Concern for the Aquatic Environment
No full textMicroplastics (MPs) are so widely dispersed and abundant throughout the globe that many scientists consider them to be important markers of the recent and current time - Plasticene. The pollution of aquatic ecosystems by plastic litter is considered a common topic of serious ecological concern. Microplastics are plastic wastes with particulates less than 5 mm in size that are absorbed by sediments, water, atmosphere, and living organisms therefore affecting environmental and human health. This review focuses on the sources, transport, fate and factors influencing the release of microplastics into aquatic ecosystems and also highlights the possible impact of these toxic micro-sized particles on aquatic lives and human health. It also discusses the available microplastic challenges, remediation and perspective for microplastic pollution management as well as green strategies for reducing microplastic contamination in water bodies. Potential ecological and health risks emanate from their ability to adsorb and transport toxic chemicals, and ease of absorption into the cells of living organisms and interfering with physiological processes. Mitigation strategies have been identified to overcome effects of the microplastics on the environment including educational campaigns aimed at improving public awareness of the plastics contamination, encouraging reuse and recycling, placing prohibitions on microplastics-free (Microbead-Free) in personal care products, putting heavy fines for plastic consumers among others. Several methods for removing microplastics, are grouped into three categories: engineered, biodegradable, and bioengineered approaches. This review promotes concise literature on microplastics and encourages further studies among researchers on this aspect of science
Influence of Social Capital Dimension on the Adoption of Organic broiler Production Practices in Anambra State, Nigeria
No full textAdoption of organic farming practices (OFP) is stimulated by adequate knowledge about the concept, resources, and access to markets. Social groups from where farmers draw their social capital play a critical role in awareness and adoption of (OFP) but have been underutilized over the years. Thus, this study examined influence of social groups on the adoption of organic broiler production in Anambra state, Nigeria. The three-stage sampling procedure was adopted to select 120 broiler farmers. Six Local Government Areas (LGAs) were selected based on their involvement in broiler production in the first stage. Two communities were randomly selected from each LGAs, and simple random sampling method was used to select ten farmers from each of the twelve selected communities. Data was collected on socioeconomic characteristics of farmers, social group participation and organic broiler production Data was analyzed using descriptive statistics and logit at α 0.05. A household belong to an average of 4.55 social groups with diversity index average of 37.73%. Meeting attendance index average was 86.74% and average monthly cash contribution was N 1,500.02/month. Years spent in school, experience, density index, training, meeting attendance index and aggregate social capital positively and significantly affect adoption of organic broiler production practices. Social capital improves the adoption of organic broiler production practices. This study therefore recommends that farmers should belong to more local level associations and attend meetings regularly
USE OF ACADEMIC SOCIAL NETWORKING SITES AND RESEARCH PRODUCTIVITY OF FEMALE ACADEMICS IN SELECTED PUBLIC UNIVERSITIES IN SOUTH-WEST, NIGERIA
No full textRegardless of gender, research productivity is paramount for career progression and prestige of academic throughout universities in the world, however, observations showed that research productivity of female academic staff in Nigerian universities is undesirably low, which is due to many reasons. This study investigated the use of academic social networking sites and research productivity of female academic staff in public universities in South-West Nigeria. Survey research design of correlative type was adopted. 1785 female academic staff in the selected universities in South-West, Nigeria comprised the population of the study. Stratified random sampling technique was used to select 536 female academic staff in the selected universities. Out of 536 copies of questionnaire distributed, 413 copies were returned. Data collected were analysed using descriptive statistics of frequency count and percentages, mean and standard deviation, while Pearson Product Moment Correlation was used to test the three hypotheses. It was found that the level of use of academic social networking sites among female academics for research productivity was moderate (= 3.61) while research productivity of female academic staff is low (= 3.15). The major purposes of use of academic social networking sites for research productivity are searching of topics/ideas for thesis, conference papers, articles 371(89.8%) and links to publish their research 344(83.3%). There is a negative relationship between use of academic social network and research productivity (r = -0.212; p = 0.000). The study among other things recommended that female academic staff should be trained by the management of the universities to improve research productivity