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Sol-Gel Synthesis And Microstructure Characterization Of Nio-Tio2 Semiconductor, Godlisten N. Shao Apr 2024

Sol-Gel Synthesis And Microstructure Characterization Of Nio-Tio2 Semiconductor, Godlisten N. Shao

Tanzania Journal of Engineering and Technology (TJET)

NiO-TiO2 is a fascinating p-n semiconducting binary metal oxide with unique electronic and optical properties. The NiO-TiO2 has been synthesized using complicated preparation methods and expensive precursors that hamper their large-scale production. The present study reports the preparation of NiO-TiO2 semiconductor with improved physicochemical properties. NiO-TiO2 samples were prepared through one-pot sol-gel synthesis process followed by sintering of the as-synthesized materials at temperatures ranging from 600 to 1000 °C. The role of thermal treatment and NiO content on the microstructures was exquisitely studied. The microstructure of the NiO-TiO2 samples was examined by Raman spectroscopy, XRD, XRF, SEM-EDAX, high resolution TEM, …


General Hydrogeochemical Characterization Of Groundwater In Coastal Aquifers Of Kilwa Kisiwani Oceanic Island, South East Tanzania, Simon R Melchioly Apr 2024

General Hydrogeochemical Characterization Of Groundwater In Coastal Aquifers Of Kilwa Kisiwani Oceanic Island, South East Tanzania, Simon R Melchioly

Tanzania Journal of Engineering and Technology (TJET)

The main objective of this study was to determine the hydrogeochemical processes controlling the groundwater chemistry on the Island and assess its suitability for human consumption and irrigation. The methodology used in the study include hydrogeological assessment of the study area and laboratory analysis for general physico-chemical parameters of groundwater. Other parameters such as Soluble sodium percentage (SSP) or % Na+, Sodium Adsorption Ratio (SAR), Magnesium adsorption ratio (MAR), Residual sodium carbonate (RSC), hydrochemical facies classification, and Water Quality Index (WQI) were calculated using empirical formulae. The effects of salinization of groundwater were classified using the chloride-Bicarbonate (Cl/HCO3) and the …


Optimal Load Shedding During Service Restoration In Electrical Secondary Distribution Network Based On Reinforcement Learning, Rukia J. Mwifunyi Apr 2024

Optimal Load Shedding During Service Restoration In Electrical Secondary Distribution Network Based On Reinforcement Learning, Rukia J. Mwifunyi

Tanzania Journal of Engineering and Technology (TJET)

Increased stress in traditional power systems results in blackouts due to voltage instability attributed to a mismatch between available capacity and load demand, especially in distribution networks. Service restoration schemes are designed to return power supply to the affected parts of the networks. The availability of insufficient supply is a complex problem that requires operational experience or an automatic system. The stochastic nature of load demand significantly impacts service restoration as it results in increased restored demand in case a fault occurs during off-peak hours and helps reduce overload if the fault occurs during peak hours. The study adopts an …


Assessment Of Risk Factors Related To Body Pain Complaints In Tanzania Construction Industry, Fatma K. Mohamed Apr 2024

Assessment Of Risk Factors Related To Body Pain Complaints In Tanzania Construction Industry, Fatma K. Mohamed

Tanzania Journal of Engineering and Technology (TJET)

The construction industry is associated with risks that can result in musculoskeletal diseases. Although young male workers who are presumed to be healthy dominate the industry in Tanzania, body pain complaints have been widely reported. The aim of this study is to assess the prevalence and causes of body pains in workers. A cross-sectional study involving 396 workers was conducted. A chi square test was used for testing association of independent categorical variables and binary logistic regression analysis was used to determine predictors for body pain complaints. The results show that all study participants complained of at least one form …


Study Of The Effects Of Thermal Aging Coupled With Shot-Peening Treatment Of Carbonitrided Din 1.6587 Low Alloy Steel On Retained Austenite And Residual Stresses, Richard J. Katemi Apr 2024

Study Of The Effects Of Thermal Aging Coupled With Shot-Peening Treatment Of Carbonitrided Din 1.6587 Low Alloy Steel On Retained Austenite And Residual Stresses, Richard J. Katemi

Tanzania Journal of Engineering and Technology (TJET)

This work investigated the effects of thermal aging and shot-peening of carbonitrided 1.6587 steel grade on retained austenite and residual stresses. After carbonitriding samples contained maximum of 0.87% carbon, 0.34% nitrogen and 50 mass. -% retained austenite. Thermal aging conditions investigated were -30°C, 90°C and 150°C while the aging period were 14, 96 and 720 hours. After thermal aging, some of the samples were subjected to shot-peening treatment using standard cut wire shots StD – G3 - 0.6 mm VDFI 8001 with intensity in the range of 0.25 to 0.30 mmA and coverage of 1.00 to 1.24 x 98%. It …


Geological Structure And Possible Mineralized Zones In Ikungi – Manyoni Area, Tanzania: Delineated From High-Resolution Aeromagnetic Data, Raymond K. Pius, Michael M. Msabi Apr 2024

Geological Structure And Possible Mineralized Zones In Ikungi – Manyoni Area, Tanzania: Delineated From High-Resolution Aeromagnetic Data, Raymond K. Pius, Michael M. Msabi

Tanzania Journal of Science

Understanding geological structures is important in mineral exploration. Delineating subsurface geological structures, structural intersections, and complexities of potential geological settings for the formation of hydrothermal mineral deposits, such as gold requires using magnetic data, particularly, high-resolution aeromagnetic data. To define possible targets for mineral exploration, this study used linear detection and the Centre for Exploration Targeting (CET) techniques on high-resolution aeromagnetic data for structural delineation and interpretation. The study's conclusions indicate that the majority of geological features, such as faults, shears, fault intersections, and fracture systems, trend NE-SW, N-S, and occasionally NW-SE. These structures create potentially large areas that have …


Extraction Of Natural Dyes From Delonix Regia Flowers For Cotton Fibres, Lutamyo Nambela, Liberato V Haule Apr 2024

Extraction Of Natural Dyes From Delonix Regia Flowers For Cotton Fibres, Lutamyo Nambela, Liberato V Haule

Tanzania Journal of Science

Textile colouration is among the major industry that pollutes the environment with effluents rich in dye chemicals. Most of the dyes used are synthetics which possess health and environmental impacts. Potentially, the use of bio-based dyes and other chemicals can lessen the environmental challenges of the textile effluents. This study reports on sustainable extraction and dyeing of cotton fabric using extract of Delonix regia flowers. The extraction process was done using acidified water as a solvent and the dyeing process was free from hazardous auxiliary chemicals. To improve the dyeing performance, banana sap was used as an affordable and eco-friendly …


The Effects Of Algal Blooms On Oxygen Levels In Lakes Babati And Eyasi, Tanzania, Amelia S. Buriyo, Nyatwere D. Mganga, Mary Melchiory Apr 2024

The Effects Of Algal Blooms On Oxygen Levels In Lakes Babati And Eyasi, Tanzania, Amelia S. Buriyo, Nyatwere D. Mganga, Mary Melchiory

Tanzania Journal of Science

Globally aquatic ecosystems are reportedly overwhelmed by algal blooms due to excessive deposition of nutrients which ultimately cause hypoxia, leading to massive fish death. This study aimed at assessing the relationship between algae contents and dissolved oxygen (DO) in Lake Babati which is threatened by anthropogenic activities, whereas Lake Eyasi was used as a control. Algae contents (chlorophyll a), DO and surface water temperature were measured using standard methods. Results revealed that the mean algae content was significantly higher (4.47±0.88 mg/L) in Lake Babati than in Lake Eyasi (1.6±0.45 mg/L) (P < 0.05) and was beyond the standard permissible levels for domestic water supply and healthy ecosystem. Conversely, DO was significantly lower in Lake Babati than in Lake Eyasi (P < 0.05). There was no significant difference in water temperature in the two lakes (P > 0.05). Furthermore, there was an inverse relationship between algae …


Angular Distribution Of Bremsstrahlung Spectral Temperature Measured In A Full Dimension Of Ecr Ion Source Using Nai(Ti) Detector, Mwingereza J. Kumwenda Apr 2024

Angular Distribution Of Bremsstrahlung Spectral Temperature Measured In A Full Dimension Of Ecr Ion Source Using Nai(Ti) Detector, Mwingereza J. Kumwenda

Tanzania Journal of Science

Measurement of angular distribution (AD) of the bremsstrahlung spectral temperature from a full dimension of the Electron Cyclotron Resonance Ion Source (ECRIS) along the beam axis is challenging. To overcome some challenges, this paper presents the AD of the bremsstrahlung spectral temperature measured in a full dimension of the ECRIS along the beam axis using data obtained from the Busan Center of Korea Basic Science Institute (KBSI). The bremsstrahlung spectral temperature from 28-GHz ECR Ion source at the KBSI was measured in six, three, and nine azimuthal angles at the injection, centre, and extraction sides of the ECRIS using three …


Influence Of Stacking Order On The Structural And Optical Properties Of Cu2znsns4 Absorber Layer Prepared From Dc-Sputtered Oxygenated Precursors, January S Gwaydi, Hezekiah B Sawa, Egidius R Rwenyagila, Nathanael R Komba, Talam E Kibona, Nuru R Mlyuka, Margaret E Samiji, Lwitiko P Mwakyusa Apr 2024

Influence Of Stacking Order On The Structural And Optical Properties Of Cu2znsns4 Absorber Layer Prepared From Dc-Sputtered Oxygenated Precursors, January S Gwaydi, Hezekiah B Sawa, Egidius R Rwenyagila, Nathanael R Komba, Talam E Kibona, Nuru R Mlyuka, Margaret E Samiji, Lwitiko P Mwakyusa

Tanzania Journal of Science

Several studies have attempted to overcome the sudden volume expansion of the precursor during sulfurization by the use of oxygen-containing precursors when growing the CZTS absorber. This work demonstrates the influence of precursor stacking orders on the properties of the CZTS thin film absorber layer from DC-sputtered oxygenated precursors for solar cell applications. CZTS absorber layers were prepared from three types of DC-sputtered stacks, namely, Zn-O/Sn/Cu, Sn/Zn-O/Cu, and Sn/Cu/Zn-O. The precursors were sequentially deposited on a soda lime glass (SLG) using DC-magnetron sputtering and annealed in a sulfur and nitrogen ambient. X-ray diffractometry (XRD) and Raman spectroscopy analyses reveal the …


Green And Blue Water Footprints Of Major Crops In The Wami/Ruvu Basin, Tanzania: Implications For Water Scarcity And Sustainability, Benson Hm Lazaro, Martine M. Hagai, Rubhera Ram Mato Apr 2024

Green And Blue Water Footprints Of Major Crops In The Wami/Ruvu Basin, Tanzania: Implications For Water Scarcity And Sustainability, Benson Hm Lazaro, Martine M. Hagai, Rubhera Ram Mato

Tanzania Journal of Science

Accurate estimation of the blue and green water requirements of the various crops cultivated in a water basin is essential for planning specific plant/crop irrigation schedules. In this study, the crop water requirements of the major crops grown in the Wami/Ruvu basin were determined using the FAO-CROPWAT model based on meteorological parameters: monthly maximum and minimum temperature, wind speed, mean relative humidity, sunshine hours, rainfall data, and effective rainfall for 23 hydro-meteorological stations distributed in the study area. The studied crops are rice, maize, beans, tomatoes, and sugarcane. The crop reference evapotranspiration (ETo) and actual evapotranspiration (ETc) for each crop …


An Assessment On The Influence Of Aridity And Vegetation Cover On Land Surface Temperatures: Case Of Dodoma Urban District, Tanzania, Carolyne Vincent Mbirika Apr 2024

An Assessment On The Influence Of Aridity And Vegetation Cover On Land Surface Temperatures: Case Of Dodoma Urban District, Tanzania, Carolyne Vincent Mbirika

Research, Papers & Creative Work

This study examines the influence of aridity and vegetation cover on land surface temperature (LST) in Dodoma Urban District, Tanzania, a semi-arid environment experiencing rapid urban growth. Using Landsat 9 satellite imagery (30 m resolution) for October 2023, key environmental variables including the Normalized Difference Vegetation Index (NDVI), Normalized Difference Moisture Index (NDMI), and LST were derived and analyzed using ArcGIS Pro. The study applies remote sensing techniques and spatial analysis to examine the relationships between vegetation, moisture availability, and surface temperature patterns. The results reveal substantial spatial variation across the study area, with NDVI values ranging from -0.17 to …


Socioecological Assessment Of Birds In Ngezi-Vumawimbi Nature Forest Reserve, Eli Taub Apr 2024

Socioecological Assessment Of Birds In Ngezi-Vumawimbi Nature Forest Reserve, Eli Taub

Independent Study Project (ISP) Collection

Effective management of natural resources requires consideration of the environment through both a physical and a sociological lens. In this study, the birds in Ngezi-Vumawimbi Nature Forest Reserve were examined through both a biological mist-net survey and a socioecological series of interviews with people living in the surrounding villages. The mist-net survey compared the understory species in undisturbed and disturbed area of the forest, as well as analyzing birds caught for biologically meaningful information on subspecies and sexual dimorphism. While the mist-net survey was largely unsuccessful, highlighting the need for alternative bird capture methods in Ngezi, it found a decrease …


Joint Environmental And Social Benefits From Diversified Agriculture, Laura Vang Rasmussen, Ingo Grass Apr 2024

Joint Environmental And Social Benefits From Diversified Agriculture, Laura Vang Rasmussen, Ingo Grass

Earth and Environmental Sciences Faculty Publications

Agricultural simplification continues to expand at the expense of more diverse forms of agriculture. This simplification, for example, in the form of intensively managed monocultures, poses a risk to keeping the world within safe and just Earth system boundaries. Here, we estimated how agricultural diversification simultaneously affects social and environmental outcomes. Drawing from 24 studies in 11 countries across 2655 farms, we show how five diversification strategies focusing on livestock, crops, soils, noncrop plantings, and water conservation benefit social (e.g., human well-being, yields, and food security) and environmental (e.g., biodiversity, ecosystem services, and reduced environmental externalities) outcomes. We found that …


Mushroom Composition Across An Elevational Gradient During The 2024 Wet Season In Mazumbai Forest Reserve, Tanzania, Christopher Brady Apr 2024

Mushroom Composition Across An Elevational Gradient During The 2024 Wet Season In Mazumbai Forest Reserve, Tanzania, Christopher Brady

Independent Study Project (ISP) Collection

Mushrooms are key bioindicators that contribute greatly to ecological health, and their diversity is indicative of a healthy ecosystem. However, even with the vital role they play in ecological health, there are few studies which measure the diversity of mushrooms in Mazumbai Forest Reserve (MFR), Tanzania, Africa, and none which focus on diversity along the elevational gradient within the reserve (1300-1900m). This study measures the diversity and equitability of mushrooms growing in six elevational zones within MFR during the rainy season of 2024. A species checklist of mushrooms growing in MFR during the 2024 rainy season was created, tracking the …


Early Report Of A Microcosm Of The Fourth Major Global Bleaching Event: A Comprehensive Survey Of Coral Bleaching At Chumbe Island Coral Park, Zanzibar, Christian Boudreaux Apr 2024

Early Report Of A Microcosm Of The Fourth Major Global Bleaching Event: A Comprehensive Survey Of Coral Bleaching At Chumbe Island Coral Park, Zanzibar, Christian Boudreaux

Independent Study Project (ISP) Collection

Coral reefs harbor a wealth of the biodiversity present in the ocean. They provide an array of ecological and economic services that make them crucial to the function of a healthy ocean and prosperous coastal communities. Due to an array of anthropogenic stressors, including an increase in ocean temperatures as a result of climate change, reefs have been devastated worldwide. This is, in large part, due to the process of coral bleaching, the expelling of symbiont algae which the coral needs to produce energy, for an extended period until death. This study surveyed bleaching and death at a deeper and …


A Study Of Anthropogenic Impacts On Echinoderms In The Jambiani Intertidal Area, Zanzibar, Amaury O. Halley Apr 2024

A Study Of Anthropogenic Impacts On Echinoderms In The Jambiani Intertidal Area, Zanzibar, Amaury O. Halley

Independent Study Project (ISP) Collection

The coastal region of Jambiani, Unguja, hosts a rich diversity of marine life within its extensive intertidal zones. Despite its ecological significance, this area is increasingly exposed to anthropogenic disturbances due to increased human activities. This study examines the impacts of these disturbances on the biodiversity, zonation, and species abundance of echinoderms in the intertidal habitats of Jambiani. Through a comprehensive field study involving fifteen transects and detailed substrate analysis, the project evaluated the distribution and abundance of echinoderm species and assessed the influence of human activities such as seaweed farming, anchor damage, and beach trampling on these communities. The …


Absorbance Enhancement Of A Treated Tanzanian Kaolin For Removal Of Synthetic Dyes From Water, Samwel Paul Mziray Feb 2024

Absorbance Enhancement Of A Treated Tanzanian Kaolin For Removal Of Synthetic Dyes From Water, Samwel Paul Mziray

Tanzania Journal of Engineering and Technology (TJET)

The absorbance efficiency of local kaolin clay from Tanzania (Pugu kaolin) has been enhanced to improve its utilization in removal of textile dyes from water. The clay was acid-activated using H2SO4, after calcination at 750oC. Characterization by XRF, XRD, ATR-FTIR and Porosimeter showed kaolinite [Al2Si2O5(OH)4], silica (SiO2) and microcline [KAlSi3O8] as the main phases. Upon acid treatment, silica increased from 44.18% to 58.81% due to the appearance of tridymite, and alumina decreased from 26.70% to 12.74% due to disappearance of the kaolinite. Surface area increased from 15.36 to 149.61 m2/g due to removal of acid-soluble impurities. The chemical composition showed …


Comprehensive Survey On Applications Of Internet Of Things, Machine Learning And Artificial Intelligence In Precision Agriculture, Paul Stone Stone Brown Macheso S.B. Feb 2024

Comprehensive Survey On Applications Of Internet Of Things, Machine Learning And Artificial Intelligence In Precision Agriculture, Paul Stone Stone Brown Macheso S.B.

Tanzania Journal of Engineering and Technology (TJET)

A comprehensive, multidisciplinary analysis of the latest developments in digital agriculture is conducted with the use of artificial intelligence (AI), machine learning (ML), and the Internet of Things. By automation and the use of modern, scalable technology solutions that reduce risks, support sustainability, and give farmers predictive advice, traditional agricultural processes are being updated and improved to maximize production. In this paper, the applications of AI, IoT, and ML in agricultural production systems are discussed in detail. The applications that have been explored can be broadly categorized into three areas: soil management, livestock management, and crop management. Weed detection, disease …


A Two-Stage Based Life Cycle And Principal Component Analysis For Decision Support Of Potential Municipal Solid Wastes Management Scenarios, Case Study Dar Es Salaam, Tanzania, Edwin Richard Ndibalema Dr Feb 2024

A Two-Stage Based Life Cycle And Principal Component Analysis For Decision Support Of Potential Municipal Solid Wastes Management Scenarios, Case Study Dar Es Salaam, Tanzania, Edwin Richard Ndibalema Dr

Tanzania Journal of Engineering and Technology (TJET)

In most of the urban areas of Tanzania, poor and inadequate solid waste management is a growing environmental and public health concern. Despite an array of solid waste management options, choosing an appropriate one remains a challenge. This study applied a novel two-stage-based approach to assess the environmental impacts and sustainability performance of the 27 scenarios for municipal solid wastes (MSW) management of Dar es Salaam City, Tanzania. In the first stage, the study utilized a life cycle analysis (LCA) to quantify the environmental impacts of MSW scenarios. In the second stage, the study used the principal component analysis (PCA) …


An Overview Of Maternity Healthcare Monitoring In Developing Nations, Godphrey Kyambille Feb 2024

An Overview Of Maternity Healthcare Monitoring In Developing Nations, Godphrey Kyambille

Tanzania Journal of Engineering and Technology (TJET)

A healthcare monitoring arrangement is essential for frequently monitoring a patient's health status. Specifically, maternal healthcare systems for tracking are utilized to evaluate the clinical status and monitor any abnormal condition changes during all three trimesters. This paper's objective is to conduct an extensive literature review and acknowledge earlier initiatives and studies conducted previously in maternal health care monitoring. This review focuses on accumulating information from earlier work and presents a general overview of previous studies concerning maternal health care monitoring (MHCM). The paper focuses on the maternal healthcare systems in developing countries accessed by pregnant women during the antenatal …


Stack For Computational Science, Mathematics And Engineering E-Learners, Idrissa S. Amour Feb 2024

Stack For Computational Science, Mathematics And Engineering E-Learners, Idrissa S. Amour

Tanzania Journal of Engineering and Technology (TJET)

Petroleum economic evaluation involves estimating revenues from forecasted production profiles and field costs including capital expenditures (CAPEX), drilling expenses (DRILLEX), and operating expenses (OPEX). The existing cost-estimating tool requires several inputs making it time-intensive and difficult to use with few data during the early stages of projects. Majority of the previously developed time saving cost estimations proxy models rely on unrealistic assumptions that include uniform operational costs for different fields with a different number of wells, casings, and drilled depths. This work focused at developing proxy models that consider the variability of the development costs with different parameters. The developed …


Effect Of Substrate Temperature And Deposition Power On The Surface Morphology And Optical Properties Of Zno:Mg Thin Films Deposited By Dc Magnetron Sputtering, Saidi Saidi, Margaret E. Samiji, Nuru R. Mlyuka Jan 2024

Effect Of Substrate Temperature And Deposition Power On The Surface Morphology And Optical Properties Of Zno:Mg Thin Films Deposited By Dc Magnetron Sputtering, Saidi Saidi, Margaret E. Samiji, Nuru R. Mlyuka

Tanzania Journal of Science

Magnesium doped zinc oxide (ZnO:Mg) thin films were deposited on soda lime glass slides by DC magnetron sputtering method. Atomic force microscope (AFM), and UV/VIS spectrophotometer were used to investigate the effect of sputtering power and substrate temperature on the surface morphology and optical properties of ZnO:Mg thin films. AFM images revealed that sputtering power and deposition temperature have significant influence on surface morphology of the ZnO:Mg thin films. For all sputtering powers and substrate temperatures investigated, ZnO:Mg films had peak transmittance above 85%. Samples deposited at 110 W sputtering power and 450 °C substrate temperature showed the best peak …


Heavy Metals Analysis And Physicochemical Characterization Of Groundwater At A Battery Recycling Site In South-Western Nigeria, Adeniyi T. Adeleke, Rasaki K. Odunaike, Shamsideen K. Alausa, Idris O. Olayiwola, Adetoro T. Talabi, Qasim A. Adeniji, Adejumobi C. Adeniyi Jan 2024

Heavy Metals Analysis And Physicochemical Characterization Of Groundwater At A Battery Recycling Site In South-Western Nigeria, Adeniyi T. Adeleke, Rasaki K. Odunaike, Shamsideen K. Alausa, Idris O. Olayiwola, Adetoro T. Talabi, Qasim A. Adeniji, Adejumobi C. Adeniyi

Tanzania Journal of Science

Indiscriminate dumping of battery waste is a huge issue that endangers human health and the environment. This study aimed at analysing the health impacts of exposure to pollution from spent battery recycling in Ogun State, which houses a diverse range of battery recycling industries. At this study site, forty water samples were studied over the Wet and Dry seasons to assess the impact of battery recycling waste on groundwater. Except for the TSS, the physiochemical parameters of the groundwater vary with season and are within the permissible limits. The electrical conductivity (EC), turbidity, Phosphorus, Biochemical oxygen demand (BOD), Dissolve oxygen …


Application Of Remote Sensing And Spectroradiometry In Geological Mapping: A Case Study Of Handeni (Qds 148) Block, Eastern Mozambique Belt, Tanzania, Masota M. Magigita, Elisante Mshiu, Cassy Mtelela Jan 2024

Application Of Remote Sensing And Spectroradiometry In Geological Mapping: A Case Study Of Handeni (Qds 148) Block, Eastern Mozambique Belt, Tanzania, Masota M. Magigita, Elisante Mshiu, Cassy Mtelela

Tanzania Journal of Science

This study applies remote sensing (RS) as a geologic mapping aid tool , using Handeni Block of Tanzania as a case study. To achieve the objective of this study, we have utilized various RS processing and image enhancement techniques on multispectral data, including ASTER, Landsat 5, Landsat 8, and Sentinel 2A. The method proved successful whereby both Landsat-5-data with band combination (BC) 7:4:2 and 7:5:4 and band ratio (BR) 5/3:5/1:7/5 and Landsat-8 data with BCs 5:6:7 and 7:6:4 mapped out marble units. Sentinel 2A data (with BC 8:11:3, BRs 12/2:11/2:8/11; 12/4:11/3:11/2 and 12/4:12/2:11/3) together with image enhancement decorrelation stretch on …


Micro Machining Of A Si3n4/Sio2/Ti/Pt Hotplate And Its Ir Emissivity Properties, Egidius R. Rwenyagila Jan 2024

Micro Machining Of A Si3n4/Sio2/Ti/Pt Hotplate And Its Ir Emissivity Properties, Egidius R. Rwenyagila

Tanzania Journal of Science

This paper presents the fabrication processes for a Si3N4/SiO2/Ti/Pt membrane based micro hotplate (MHP) using photolithography (PL) micro-machining techniques. The properties of the MHP filament are investigated and overall performance characteristics with regard to infrared (IR) radiation emissivity, resistance, breakdown voltage, and temperature of the fabricated Si3N4/SiO2/Ti/Pt micro heater. During characterization, the results show the device breakdown voltage of 24.24 V corresponding to the optimum operation temperature of ~ 1730.30 K. The device also showed an emissivity value of 5.2% with ~ 7% efficiency of transforming electrical power to IR thermal radiation power. The relationship between temperature and resistance, behaviour …


Preparation Of 2d Tungsten Diselenide (Wse2) Thin Films By Selenization Of Dc-Sputtered W Precursors, Lwitiko P. Mwakyusa Jan 2024

Preparation Of 2d Tungsten Diselenide (Wse2) Thin Films By Selenization Of Dc-Sputtered W Precursors, Lwitiko P. Mwakyusa

Tanzania Journal of Science

Two-dimensional layered transition metal dichalcogenides based on WSe2 films demonstrated promising properties for nano-electronics and photovoltaic applications. In this work, WSe2 films were prepared by selenization of DC-sputtered W precursors. The influence of the selenization temperature on the structural, morphology, and optical properties of the WSe2 films was investigated. The selenization temperature was varied from 350 °C to 450 °C at the interval of 50 °C. Structural, morphology and optical properties of the WSe2 were investigated using X-ray diffractometry (XRD), Atomic Force Microscope (AFM), and UV-VIS-NIR spectrophotometer, respectively. XRD analysis revealed that all WSe2 were polycrystalline and exhibited the co-existence …


Quantifying The Strength Of The El Niño Southern Oscillation And The Indian Ocean Dipole In Influencing The Ond Rainfall Season In Tanzania, Benjamin William Ongito, Paul T.S. Limbu Jan 2024

Quantifying The Strength Of The El Niño Southern Oscillation And The Indian Ocean Dipole In Influencing The Ond Rainfall Season In Tanzania, Benjamin William Ongito, Paul T.S. Limbu

Tanzania Journal of Science

The current paper examines the strength of variability between the El Niño-Southern Oscillation (ENSO) and the Indian Ocean Dipole (IOD) in influencing October to December (OND) rainfall over the bimodal rainfall regime of Tanzania. The empirical orthogonal function (EOF), correlation analysis, and composite analysis were used during the data analysis. The results show more rainfall distribution over the western part of the Lake Victoria basin and to the peripheral of the northern coast of the country, thus suggesting that, during the OND rainfall season, the onset starts in the western part of the Lake Victoria basin, then spreads to the …


Modelling Spatial Distributions Of Sediments Fingerprinting In The Ruvu Basin Of Tanzania Without Continuous Sediment Monitoring, Charles H. Kasanzu Jan 2024

Modelling Spatial Distributions Of Sediments Fingerprinting In The Ruvu Basin Of Tanzania Without Continuous Sediment Monitoring, Charles H. Kasanzu

Tanzania Journal of Science

This study investigates various hinterlands’ contribution of sediments into the sub-basin known as Ruvu that comprises Mindu, Kibungo, Mvuha and Mindu catchments of Morogoro, Eastern Tanzania. An integrated geochemical and isotopic data were used to constrain this. Strategic sampling of basement and silty-sized sediments was conducted and the data were modelled using mass-balance computations. This approach revealed that, more than 70% of suspended sediments in the Mgeta River originate from Kigalamila, Sezima, Kingule, Mafumbo and Kibuko areas. Thus, hills north of Kisaki are major contributors of sediments with less contribution from the southern terrain. After modelling of the data from …


Turmeric Dyeing Of Cotton Fabrics Using Tie-Dyeing Techniques, Pendo Bigambo, Happiness Wellah, Hadija Ngaga, Safina Kimbokota, Mbonea Mrango Jan 2024

Turmeric Dyeing Of Cotton Fabrics Using Tie-Dyeing Techniques, Pendo Bigambo, Happiness Wellah, Hadija Ngaga, Safina Kimbokota, Mbonea Mrango

Tanzania Journal of Science

Tie-dyeing is a resist-dyeing technique which for years has been used by SMEs to produce attractive textile fabrics. However, the technique is challenged by the use of synthetic dyes which are not environmentally friendly and the growing consumers’ environmental awareness. Accordingly, researchers and industrialists are forced to explore the alternative natural dyes in response to the above challenges. Among the natural source of dyes available abundantly in Tanzania, but are yet to be fully exploited for applications via tie-dyeing technique are turmeric (Curcuma longa L.) roots commonly used for food coloring. In this study turmeric roots were investigated for their …