Nigerian Journal of Technology最新文献

{"title":"Filter media enhanced electrokinetic remediated crude oil contaminated soil: investigation of its engineering properties and its suitability for road construction","authors":"K. Adebayo, G. Moses, J. S. Engbonye, B. Ibrahim, F. Balarabe","doi":"10.4314/njt.v42i2.3","DOIUrl":"https://doi.org/10.4314/njt.v42i2.3","url":null,"abstract":"Research have shown how electrokinetic remediation (EKR) technology attempts to tackle the challenge of soil contamination by crude oil. However, the suitability of the resulting remediated soils for use in road construction have not been well reported. This work investigates the engineering properties of filter media enhanced electrokinetic remediated crude oil contaminated soil (COCS) with a view to ascertain its suitability for use in road construction by comparing the performance of charcoal and active carbon as filter materials. COCS collected at a depth of 1m from the Nigerian Pipeline and Storage Company, Kaduna was remediated by using graphite electrodes to pass 1V DC/cm across EKR setups enhanced by incorporating a 1cm thick charcoal and active carbon separately as filter materials across the setups. Average removal efficiencies of 81.4% and 84.6% were obtained against the 78,600 mg/kg oil content of the COCS from charcoal and active carbon filter media enhancements respectively. This showed that active carbon, with higher removal efficiency, is a better filter medium for COCS than charcoal. The compaction and California bearing ratio (CBR) properties of the COCS also improved with the filter media enhanced EKR. However, the CBR values for the filter media enhanced EKR soils only meet the 20% minimum requirements for Type 2 sub-base course materials specified for light trafficked Nigeria roads. As such, charcoal or active carbon filter media enhanced EKR technology can be adopted for remediating COCS for light trafficked Nigeria road construction in areas not subjected to flooding.","PeriodicalId":33360,"journal":{"name":"Nigerian Journal of Technology","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-08-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42223128","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Assessment of solid waste management in Ota, Ogun State, Nigeria","authors":"A. David, O. O. Odagbodo, O. Opafola, G. Amusan, A. A. Badejo, O. Olaniyan, O. Onabanjo","doi":"10.4314/njt.v42i2.18","DOIUrl":"https://doi.org/10.4314/njt.v42i2.18","url":null,"abstract":"The rapid rate of population growth and urbanization has impacted the management of municipal solid wastes (MSW) and is increasingly becoming a major concern in many cities in developing countries. Insufficient area coverage for wastes collection, processing system, and unsuitable disposal all appear to be the causal factors. This paper discussed the current situation of solid waste management in Ota municipality as well as the challenges and associated problems. Structured questionnaires, interviews and on-site observations were used for data generation, and subsequently analyzed using descriptive statistics. Results indicated that 28.6% of the respondents incinerate their wastes, while 27.6% of the respondents dispose theirs to public waste bins. About 11.4% deposit their wastes by the road side, while 6.4% dump their wastes in drainages and water bodies. Most respondents incinerate their wastes which would impact negatively on the ozone layer. Results also indicated that 54.3% of the respondents have their wastes disposed regularly, while 66% do not sort their wastes which make them difficult to manage. The city's single dump site was visited in order to have a better understanding of the existing solid waste management measures in place. Other illegal waste dumps in the town were also visited. In order to address the difficulties of solid waste management in the municipality, it is recommended that the state government engage additional Private Service Provider (PSP) operatives to assist with waste collection and transportation, provide suitable facilities, machinery, and equipment, and launch a public awareness campaign","PeriodicalId":33360,"journal":{"name":"Nigerian Journal of Technology","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-08-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41983871","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Synthesis and characterization of mehtylammonium bismuth iodide via solvent engineering","authors":"B. Abdulkareem","doi":"10.4314/njt.v42i2.10","DOIUrl":"https://doi.org/10.4314/njt.v42i2.10","url":null,"abstract":"Hybrid organic–inorganic halide perovskites (OIHPs) are an emerging class of photovoltaic materials that have gained tremendous attention in the field of optoelectronics. This work aims to investigate the characteristics of bismuth-based halide perovskite via solvent engineering for solar cell application. A bismuth-based organo-inorganic perovskite was synthesized and characterized for solar cell application via solvent engineering using Gamma Butyrolactone (GBL) as the based solvent and enhanced with Methylamine (MA) and acetonitrile (ACN). A solution processing facile method was adopted in the synthesis of the perovskite. The solvent engineering aims to tune its band gap and a remarkable band gap of 1.58eV which is within the range of an ideal band gap (1.5-1.6) required for solar cell application. The XRD micrograph exhibited several narrow sharp peaks which indicated crystallinity formation of the synthesized sample with 86% crystallinity. The FESEM/EDS micrograph indicated nature of the formed crystals and the chemical composition of the sample. A multilayer heptagonal crystal was observed. The TGA result showed that the sample is thermally stable at a temperature of 200oC before degradation occurred.","PeriodicalId":33360,"journal":{"name":"Nigerian Journal of Technology","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-08-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43168352","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Determination of reference service life for reinforced concrete multistorey residential buildings: case study of Akure, Nigeria","authors":"J. O. Ilevbaoje, C. Arum, A. Omoare","doi":"10.4314/njt.v42i2.7","DOIUrl":"https://doi.org/10.4314/njt.v42i2.7","url":null,"abstract":"The Service life of a building is the period from commencement of service to the time just before costly maintenance becomes necessary for continued meeting of minimum performance requirements. Knowledge of service life determines whether to demolish and replace a building or major repairs are required and the absence of information on this has led to many building failures. This research therefore aimed to determine the Reference Service Life (RSL); a parameter required for the evaluation of a building’s Service Life. Twenty reinforced concrete multistorey residential buildings around the Federal University of Technology Akure (Nigeria) were assessed via visual inspection, material testing, and structural analysis. Information obtained from the assessment was used to develop a comprehensive open-ended service life database. Non-destructive tests were conducted on the buildings’ structural elements and the results used to determine the service life of each of the buildings with the aid of Life 365 Software. Weighted factors which depend on the quality characteristics, operational conditions and the environment of the buildings were used as a grading system for the assignment of sub-factors for the adjustment of the Life 365 service life values, leading to a value of 29 years as the Reference Service Life (RSL) for the study area. The result obtained will benefit construction professionals and appropriate regulatory authorities in the study area while the procedure can be adopted for service life assessment in other locations lacking appropriate database.","PeriodicalId":33360,"journal":{"name":"Nigerian Journal of Technology","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-08-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48237128","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Incorporating grain detection and speed control mechanisms in hammer mill operations","authors":"A. Oyelami, A. Oluwole","doi":"10.4314/njt.v42i2.9","DOIUrl":"https://doi.org/10.4314/njt.v42i2.9","url":null,"abstract":"The traditional way of achieving different grain particle sizes in hammer mills is by manually changing the screen to the desired size. This manual process is a production procedure that is time-consuming, demanding, and resource-draining. This study incorporated a grain identification and speed control mechanism into a hammer mill machine. The grain detection mechanism is a system that recognizes a grain type through an RGB (Red, Green, Blue) colour sensor. The system has been programmed and trained to vary the speed of a 2hp electric motor with a maximum speed of 2800rpm based on the colour-matching result obtained when the grain is scanned on the colour sensor. The machine was evaluated using performance parameters such as power consumption and grain sieve analysis of milled grains using three crops (yellow corn, white corn, and cowpea). The Three crops were programmed for milling at three motor speeds (2800rpm, 2200rpm, and 1800rpm), and the result is presented. This paper showed that fine, medium and coarse aggregates were obtained for all three-grain types by varying motor speeds, eliminating the need to manually change the screen. The system was responsive to grain identification and speed selection as programmed.","PeriodicalId":33360,"journal":{"name":"Nigerian Journal of Technology","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-08-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41437583","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Opto-electronic and electrochemical evaluations of particulate wo3 and sno2 in electrocodeposited Zn- tio2 nanocomposites coatings for sensor application","authors":"A. A. Daniyan","doi":"10.4314/njt.v42i2.8","DOIUrl":"https://doi.org/10.4314/njt.v42i2.8","url":null,"abstract":"This study synthesized, characterized and determined the electronic and optical properties of Zn-TiO2, Zn-TiO2-WO3 and Zn-TiO2-SnO2 nano-composite coatings on low carbon steel. It has also determined the effect of these coatings on the corrosion of mild steel in saline environment. This was with a view to produce an active coating to providing alternative to hazardous chromium coating. Active multi functional nano crystalline coatings of the composites were electrolytically fabricated on low carbon steel from Zinc bath, with its Cation and nanoparticulates of TiO2, SnO2 and WO3 were uniformly codeposited in the Zn matrix. The nano-powders were characterized with Scanning Electron Microscope/Energy Dispersive Spectrometer (SEM/EDS) analyses for confirmation of the chemical compositions and purity. The electrocodeposition bath compositions were developed with 120 gram per litre of ZnCl2, 30 gram per litre of KCl along sides with the nanopowders. Other additives including cetylpridinum chloride, 2- Butyne 1,4diol were added as surfactants and Thiourea was added as stabilizer. The coated specimens were sectioned into parts, some of which were characterized with electrical meters and solar simulator to determine the electrical conductivity and solar response of the coated samples respectively. Samples were also subjected to corrosion experiment in 3.5% NaCl (saline) media to study their corrosion resistance properties in the test media through Potentiodynamic polarization method. The results, the electrical conductivity of the generated nano-composite coatings displayed a better electrical conductivity of 2.45E-01Ω-1m-1 which made it a better sensor material and outstanding corrosion resistance with corrosion rate at 0.10116 mm/year. The study concluded that both matrices with the Nano Particulate WO3 and SnO2 can be use as sensor materials but the WO3 matrix showed a better electrical conductivity both in the presence and absence of uv light and enhanced corrosion protection under light and dark conditions, thus a better sensor’s material.","PeriodicalId":33360,"journal":{"name":"Nigerian Journal of Technology","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-08-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48323392","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Valorization of food waste for biogas production; effect of co-ensiling with maize straw at different C/N ratios","authors":"J. Undiandeye, S. Kiman, M. Abubakar, H. Mohammed","doi":"10.4314/njt.v42i2.17","DOIUrl":"https://doi.org/10.4314/njt.v42i2.17","url":null,"abstract":"Food waste (FW) contribute to emission of greenhouse gases as well as environmental pollution. One way of reducing the impact of FW on the environment is by using it for biofuel production. The yield of biofuel from FW can be improved if the substrate is pretreated. In this study, ensiling was used as a cost effective method of pretreating FW for biomethane production. Co-ensiling of FW and maize straw (MS) was carried out at carbon to nitrogen ratios (C/N) of 20, 25, 30 and 35 for 210 days at ambient temperature. Thereafter, the biomethane potential (BMP) of the silages was determined using an automatic biomethane potential test system. Results showed that ensiling reduced both structural and non-structural carbohydrate components of the silages. BMPs of 385.58, 497.39, 520.53, 551.37, 542.16 and 517.29mL/gVS from the unensiled FW, ensiled FW without MS, co-ensiled FW at C/N ratio of 20, co-ensiled FW at C/N ratio of 25, co-ensiled FW at C/N ratio of 30 and co-ensiled FW at C/N ratio of 35 respectively were obtained. A kinetic evaluation showed that the dual pool model gave a better prediction of the experimental BMP of all substrates than the first-order model and the modified Gompertz model.","PeriodicalId":33360,"journal":{"name":"Nigerian Journal of Technology","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-08-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44834484","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Evaluation of compressive strength and abrasive properties of rice husk ash – cement compressed stabilized earth bricks","authors":"A. O. Olumodeji, F. Ayodele, K. Oluborode","doi":"10.4314/njt.v42i2.5","DOIUrl":"https://doi.org/10.4314/njt.v42i2.5","url":null,"abstract":"Cement, the most utilized building material in developing countries like Nigeria, is rising daily, making it hard for low-income people to acquire a home. This study aimed at producing compressed stabilized earth bricks (CSEBs) from Rice Husk Ash (RHA) and cement. After uncontrolled calcination of rice husk, the RHA oxide compositions were assessed by X-Ray Fluorescence. Design Expert (RSM) designed mix proportions for seventeen earth brick variables. Cement-RHA-Soil was blended with 0-5% cement and 20-25% water. Box Behnken Design (BDD) of Response Surface Methodology (RSM) in Design Expert Version 6 was used to generate seventeen (17) design mix proportions (variables) for the CSEBs. After damp curing for three days, compressed stabilized earth bricks (CSEBs) were evaluated for compressive strength and abrasion at 28, 56, and 108 days. RHA was pozzolanic because its major oxides (SiO2, Al2O3, and Fe2O3) yielded 75.27%. CSEB compressive strength improved with age. RCB16- CSEBs with 2.5% RHA+2.5% Cement+21.25% WC - exhibited the best compressive and abrasion strength. Thus, RHA is a good cement replacement in CSEB production for cheaper and sustainable building.","PeriodicalId":33360,"journal":{"name":"Nigerian Journal of Technology","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-08-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43674905","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Linear programming model for scheduling bus rapid transit in Lagos State, Nigeria","authors":"A. Mogbojuri, O. Olanrewaju, A. Adeyeye","doi":"10.4314/njt.v42i2.11","DOIUrl":"https://doi.org/10.4314/njt.v42i2.11","url":null,"abstract":"The amount of time users have to wait influences their mode of transportation choice. Commuters don’t like to wait in the bus station, especially when the weather is terrible and for the purpose of keeping appointments. Scheduling buses to the various bus terminals will meet the commuter’s needs. The aim of the study is to reduce the waiting time of commuters at bus station and to assign buses to each route. A mathematical model called linear programming (LP) was developed to schedule buses to improve the smooth process of the Bus Rapid Transit (BRT) system. The linear programming model was applied to the Lagos Metropolitan Area Transport Authority (LAMATA) data in Lagos State. The proposed method generated three (3) shifts from 6 – 11am in the morning, 11 – 4pm in the midday and 4 – 9pm in the evening subject to two (2) shifts of fifteen (15) hours to reduce the number of hours buses operate per day and also allocated buses for each route for weekdays with five (5) hours per each shift instead of seven (7) hours buses operated per shift. A properly implemented strategy would significantly decrease passengers' long waits at bus stops, reduce the breakdown of buses, man-hours lost, and allows commuters to meet their various schedule for works, meetings, and other assignments.","PeriodicalId":33360,"journal":{"name":"Nigerian Journal of Technology","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-08-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43270473","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effects of sodium carbonate admixture and mix design ratios on the compressive strength of concrete","authors":"O. Andrew, O. Omotayo, C. Arum, C. Ikumapayi","doi":"10.4314/njt.v42i2.4","DOIUrl":"https://doi.org/10.4314/njt.v42i2.4","url":null,"abstract":"This study aimed to investigate the impact of sodium carbonate (Na2CO3) admixture on the acceleration and long-term compressive strength of ordinary Portland cement (OPC) concrete at different mix ratios. Concrete cube specimens (150 × 150 × 150mm3 size) were cast at three different mix ratios (1:1.5:3, 1:2:4, and 1:3:6) with sodium carbonate admixture added in increasing dosage of 0.5% from 0 to 2.0% by weight of OPC. Compressive strength tests were conducted on the cast specimens after curing under water for 7, 28, 56 and 90days. Additionally, tests were done to see how sodium carbonate would accelerate setting times of OPC paste. The results of the tests showed that Na2CO3 decreased the initial and final setting times of cement paste from 96 to 67mins and 543 to 387mins respectively. Compressive strength test results for 1:2:4 and 1:3:6 mix ratios showed an increasing trend up to 1.0% Na2CO3 admixture, after which there was a decrease. Meanwhile, 1:1.5:3 mix ratio showed a decrease in strength from 21.87 N/mm2 at 0% to 14.90 N/mm2 at 1.0% Na2CO3 addition, after which the strength increased with Na2CO3 percent addition. These results suggest that sodium carbonate has an accelerating effect on concrete setting time, and may aid its early strength development, but has negative long-term effects on concrete strength with increasing dosage. An optimal percentage of 1% Na2CO3 by weight of OPC is advised for accelerating effects in concrete, based on the results of this study.","PeriodicalId":33360,"journal":{"name":"Nigerian Journal of Technology","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-08-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45127528","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}