Journals National University of Science and Technology (NUST)
Not a member yet
174 research outputs found
Sort by
Membrane technology in tannery wastewater management: A review
Get PDFThe leather industries is a key and viable sector of the economy of many emergent countries, but it is also recognised as one of the highest polluting industries. This is as a result of the discharge of vast amounts of chemical containing water employed in the leather making process into the environment with little or no treatment. Nearly 40-45 litres of water are used per kilogramme of raw hide processed into finished leather. However, of the total amount of water employed in the leather making process approximately 90% is discharged into the environment as effluent. As such, a large amount of noxious effluent is produced having huge chemical oxygen demand and biochemical oxygen demand, suspended and dissolved solids, chromium, surfactants and other toxicities. It is therefore vital to adequately treat/detoxify the tannery wastewater for environmental safety. Various methods are available for the treatment of tannery wastewater. The numerous physiochemical techniques used for wastewater treatment can also be applied to tannery wastewater (to the entire process or to individual step in the process). However, conventional treatment methods have certain limitations in real field of tannery wastewater treatment arena. Membrane technologies gain importance in this regard. This paper provides an insightful review on the environmental pollution and toxicity characteristics of tannery wastewater and chemicals. Moreover, traditional treatment methods, their advantages and disadvantages, for tannery wastewater are briefly discussed. Membranes, their classifications and available preparation techniques are briefly reviewed. Finally, advances in the membrane treatment approaches used for the treatment and/or detoxification of tannery wastewater at both laboratory and pilot/industrial scale are evaluated. In addition, integrated membrane treatment approaches alone or in combination with physicochemical and biological treatment approaches are also considered
High Temperature Creep Measuring Apparatus
Get PDFA high temperature creep measuring apparatus capable of operating over a wide range of temperatures, humidities and stress levels was developed. To assess its reliability, the apparatus was used to measure the creep behaviour of nylon6.6 tyre materials, under different temperature and humidity operating modes. At all operating conditions, cords exhibited instantaneous extensions on loading followed by steady creep over time with aneventual failure. The results obtained using the apparatus tallied well with results by other researchers, and this indicates that the apparatus can be used as a reliable measuring instrument
Foreword Editorial for First Issue
No full textThe Southern African Journal of Communication and Information Science (SAJCIS) is an outcome of eight successfully hosted conferences by the Faculty of Communication and Information Science at the National University of Science and Technology (NUST). The 7th and 8th ICCIS produced peer reviewed proceedings and there was determination not only to produce peer reviewed proceedings but an accredited journal. The SAJCIS is a peer-reviewed journal that aims to provide research on current developments in the management of information. The journal aims to understand policies and practices in the broader themes of Records and ArchivesManagement, Journalism and Media Studies, Library and Information Science and Publishing Studie
SENSITIVITY OF SOME PATHOGEN ISOLATES TO FUNGICIDES COMMONLY USED IN VEGETABLE GREENHOUSES IN ZIMBABWE
Get PDFThe adoption of greenhouse technology for the production of high value vegetables is on the increase in Zimbabwe. This production system is chemical intensive in pest, disease and mineral nutrition management. This study sought to survey the prevalence of fungal diseases in greenhouse grown tomatoes, cucumber and green pepper in and around Bulawayo and to investigate the sensitivity of the isolated fungal pathogens to commonly used fungicides. Infected plant parts were collected for laboratory analyses from clearly diseased plants. Six fungal pathogens, namely Phytophthora infestans, Fusarium oxysporum f. Sp lycopersici, Peronospora, Botrytis cinerea, Leveillula taurica and Spaerotheca fuliginea, were isolated from these crops in the laboratory. These fungal isolates were evaluated for their susceptibility to the following commonly used fungicides: Copper Oxychloride, Chlorothalonil, Dithane M-45, Saaf and Didecyl Dimethyl Ammonium Chloride (DDAC – Spore Kill), using the broth macro-dilution method. The fungal isolates showed varied sensitivity to the test fungicides. All fungal isolates were completely inhibited by all the concentrations of Copper Oxychloride and Chlorothaloni used, except for Phytophthora infestans, which showed resistance at all the concentrations of these fungicides used, and Fusarium oxysporium which was resistant to 0.075 % Chlorothalonil. Both Dithane and Saaf were able to inhibit fungal growth at the recommended concentration, i.e. 0.2 %. Spore Kill (DDAC) completely inhibited all the fungal isolates at all the concentrations used. The best fungicidal activity was obtained with Spore kill, followed by Copper Oxychloride and then Chlorothalonil. Phytophthora infestans displayed resistance to all the fungicides except to Spore Kill, followed by Fusarium oxysporium. Botrytis cinerea was the most susceptible isolate to all the fungicides tested. All fungicides were effective at, or just below, their recommended concentration levels, except for Spore Kill which was effective across the board. Even though Spore Kill is a recent addition to the fungicides currently in use in greenhouses in Zimbabwe, the results of this study show that it can be adopted as a preventative fungicide in greenhouses with high levels of success
Determination of sedimentation thickness within the Eastern part of Benue Trough, Nigeria from high resolution aeromagnetic data
Get PDFThe estimation of basement depth within the eastern part of Lower Benue Basin was based on both Source Parameter Imagingand Spectral method of analysis of the high resolution Aeromagnetic data covering the study area. The total area covered is18,150 km2 which include Markudi, Gboko, Otukpo Agena, Akwana, and Katsina-Ala, all in Benue state of Nigeria. The areaisbounded by latitude 70.00' and 80.00' and longitude 80.00’and 90.50’. The aeromagnetic data was subjected to Vertical derivative, Analytical signal, Source parameter imaging SPI) and spectral depth analysis. These derivatives help demarcate regions of relatively thick sedimentation and regions of basement rock outcrop and intrusions into sedimentary formations at shallow depth. Maximum depth of sedimentation from SPI method is 4.146 Km which is located at the Eastern edge below Akwana, depth in the range of 3 Km were also obtain at the Western edge below Gboko, Makurdi and around Agena. Shallow sedimentations were observed at the South Eastern and North Eastern corner of the study area. Result from the spectral depth analysis give depth values that varies from 2.36 Km to 5.42 Km. Results from these two methods correlate in location and value. Regions with depth estimate above 4 Km could be explored for hydrocarbon and gas exploration. The South-Eastern corner and the North-Eastern corner of the study area which depict consolidated lithology at relatively shallow depths can serve as locations for water reservoirs at the height of rainy seasons to avoid flooding
Leadership in food security: African traditional and humanitarian organisations’ leadership perspectives in food aid delivery. A case of Matabeleland in Zimbabwe
Get PDFRelief food aid delivery has failed in Africa to create beneficiary resilience in recurring drought and famine disasters. The deliveries of food aid to starving recipients delay or the food quantities delivered never match the amount and type of food needed. The traditional leadership participation is lacking at designing, planning and very limited at the implementation of the emergency response. Humanitarian relief aid leadership focuses onfulfilling the donor mandates and the rights of beneficiaries to adequate food. It is oblivious to the needs of the food recipients due to the leadership’s ignorance of beneficiaries’ traditional and indigenous coping methods against famine disasters. African traditional leadership has, however, had household and community coping mechanisms against drought and famine disasters, but the leadership is ignorant about the operations of contemporary humanitarian relief food aid leadership. This research assesses traditional and relief aid NGOs leadership mechanisms that can increase food aid beneficiaries’ resilience against progressive drought andfamine disasters. The study was qualitative and semi-structured interviews were used to collect data that was analysed using MAXQDA (2018) that generated leadership thematic classifications in response to drought and famine disasters. The traditional and relief aid nongovernmental organisations’ leadership mechanisms contrasts in the study of food security resulted in three main leadership outcomes, namely Knowledge, creativity and adaptation for traditional leadership and limited outcomes and focus for the non-governmental organisations’ leadership. The research also highlights that the basis of the success of the traditional leadership model in ensuring food security is the relationship with and dependence on the natural environment produce
Fatty acids composition and oil characteristics of nut kernel oil of cashew (Anarcadium occidentale L.)) from Nsukka, Nigeria
Get PDFThe lack of information on the fatty acid content and physicochemical profile of nut kernel oil from the eastern part of Nigeria, necessitated the present study. The physicochemical properties and fatty acid profile of kernel oil obtained from cashew nuts from Nsukka community, in Enugu State, Nigeria, was investigated using standard methods. The properties of the oil were: colour (yellow), moisture impurity (1.09%), refractive index (1.86), specific gravity (0.90), acid value (19.58 mg KOH g-1), saponification value (230.01 mg KOH g-1), iodine value (119.72 mg iodine g-1), peroxide value (0.00 mmol kg-1 of active oxygen), free fatty acid value (98.0 g·kg-1), unsaponifiable matter (23.0 g·kg-1), total lipid content of kernel (425.0 g·kg-1), fatty acid content of kernel (340.0 g·kg-1), saturated (74.4 g·kg-1) and unsaturated (265.6 g·kg-1) fatty acid content of kernel. Fatty acid profiling showed the oil to be very rich in oleic (59.95%), linoleic (17.33%), palmitic (14.72%) and stearic (6.78%) acids, with a linoleic to linolenic acid ratio of 84.99. The oil contained 77.70% unsaturated fatty acids, 29.15% of which were polyunsaturated. This result indicates that the oil is of good quality, relatively rich and safe for consumption; is semi-drying and may be suitable for soap making
Statistical Analysis of Road Traffic Accidents Fatality Using Poisson and Negative Binomial Regression (Case Study of Osun State Frsc)
Get PDFThis study focuses on investigating the effectiveness of water melon rind in phenol removal from aqueous solution. The effects of various parameters (pH, initial phenol concentration, biosorbent dosage and contact time) on phenol adsorption were investigated. The pH of 2, initial phenol concentration of 40 mg/L, biosorbent dosage of 0.6 g and contact time of 6 h also deduced to be the optimum conditions for the adsorption process. The maximum phenol removal under optimized conditions was 85%. The sorption data fitted to the Freundlich isotherm with a regression coefficient of 0.9824. The kinetics was best described by the intraparticle diffusion model and Elovich equation with regression coefficients of 1 and 0.8461 respectively showing that the reaction is chemisorption on a heterogeneous surface and the intraparticle diffusion rate only is the rate determining step. The study revealed that water melon rind have a potential of removing phenol from industrial wastewaters
Pesticide residues in ginned cotton and gin motes. Case study of Zimbabwe
Get PDFPesticides that are applied by farmers on cotton can find their way to further processes such as ginning. The contamination of cotton lint and cotton waste (such as gin motes) from the ginning process with pesticides leads to a compromise in the cotton lint quality for lint intended to be sold to the export market and may also be a source of health risk due to exposure to pesticide residues. This study therefore set forth to determine the levels of endosulfan, carbaryl, dimethoate, lambda cyhalothrin and fenvalerate in ginned cotton and gin motes. Samples were obtained from two local ginneries and soxhlet extraction was used for isolation of the pesticide residues followed by sample clean-up using solid phase extraction (SPE). The analytical procedure was done using gas chromatography with electron capture detector (GC/ECD) for endosulfan and liquid chromatography tandem mass spectrometry (LC/MS/MS) for carbaryl, dimethoate, fenvalerate and lambda cyhalothrin. Results indicated that concentrations of carbaryl and dimethoate in all samples were below detection limits. In ginned cotton maximum concentrations of endosulfan, fenvalerate and lambda cyhalothrin were 0.93ppm, 0.37ppm and 0.06ppm respectively and for gin motes 0.33ppm, 0.33ppm and 0.09ppm respectively. The presence of pesticide residues in ginned cotton and gin motes was attributed to intensive application of pesticides during cotton farming and use of persistent pesticides such as endosulfan at later stages of the plant growth
Preparedness of the book sector in Zimbabwe for the development of e-learning materials for the new curriculum
Get PDFPurpose: In January 2017, the Zimbabwean government implemented a new curriculum for the primary and secondary school education level emphasizing e-learning. This has implications on the publishing sector, producing the new curriculum's necessary teaching and learning resources. However, there is no e-learning policy in Zimbabwe and the availability of infrastructure for elearning is of concern. The study sought to explore the e-readiness of the local textbook publishers for the new curriculum by establishing the availability of e-content, ascertaining schools’ capacity to implement e-learning and ascertain the availability of skilled e-content producers.
Methodology: This was a qualitative case study that adopted open-ended questionnaires and interviews for data collection. The study participants were purposively drawn from educational publishers and primary schools in the Bulawayo Metropolitan Province.
Findings: The findings revealed a lack of stakeholder preparedness to implement the e-learning initiative and inadequate e-learning infrastructure.
Implications: The study will influence policy and practice in developing textbooks and other teaching and learning materials for the new curriculum, emphasising e-learning.
Originality: The unplanned implementation of the new curriculum for the primary and secondary education system in January 2017, coming on the heels of the curriculum review consultations which had just ended in the mid-year of 2016, prompted the need to establish the preparedness of developers of textbooks and other learning materials for this move