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Qualitative And Numerical Observations Into The Career Trajectories Of Early Career Academics: A Mathematical Model Approach, Oluwatayo M. Ogunmiloro Jan 2026

Qualitative And Numerical Observations Into The Career Trajectories Of Early Career Academics: A Mathematical Model Approach, Oluwatayo M. Ogunmiloro

Tanzania Journal of Science

This study develops and analyzes a mathematical model that describes the interplay among different researcher groups within academia by focusing on how variables such as mentorship, access to funding, and academic peer influence affect the career trajectories of early-career, experienced, redundant, and successful researchers. Using stability theory and relevant theorems of differential equations, this study ensures the existence, uniqueness, positivity, and boundedness of the model's solutions. Additionally, the model’s equilibrium states, are analyzed to determine the local asymptotic stability. Numerical simulations using the Runge-Kutta fourth-order (RK4) method, implemented in Python, are performed to illustrate issues related to career growth within …


Thermal Performance And Specific Energy Consumption Of Traditional Tobacco Curing Barns In Tanzania, Seuri S. Kilakoi, Baraka Kichonge, Thomas Kivevele, Mtaki T. Maagi, Jacob B. Lisuma Jan 2026

Thermal Performance And Specific Energy Consumption Of Traditional Tobacco Curing Barns In Tanzania, Seuri S. Kilakoi, Baraka Kichonge, Thomas Kivevele, Mtaki T. Maagi, Jacob B. Lisuma

Tanzania Journal of Science

Traditional tobacco curing barns remain the dominant technology in Tanzania due to their low construction cost and accessibility, particularly in major producing regions such as Tabora. However, their thermal inefficiency results in excessive firewood use and environmental degradation. This study presents a field-based performance evaluation of a traditional flue-curing barn at the Tobacco Research Institute of Tanzania. Environmental parameters and fuel consumption were monitored at 15- minute intervals throughout the yellowing, leaf drying, and stem drying stages. The curing process handled 429 kg of fresh tobacco using 1,016 kg of firewood, equivalent to 16,256 MJ of energy input. The specific …


Cross-Temporal Statistical Approaches For Evaluating Predictor-Outcome Relationships, Jeff Joseph Jan 2026

Cross-Temporal Statistical Approaches For Evaluating Predictor-Outcome Relationships, Jeff Joseph

Dartmouth College Ph.D Dissertations

Central auditory function is linked with cognitive deficits, but few research projects use existing statistical approaches or develop new ones to forecast cognitive deficits using the results of central auditory tests. To address this limitation, we use a series of statistical learning frameworks for predicting a child’s cognitive abilities based on his/her central auditory performances and demographic factors. Two key challenges exist. First, children may start the study at a time when they are unable to perform the central auditory tests or cognitive tests. Second, cognitive performance is age-dependent, particularly in the early formative years of childhood and adolescence. To …


Geochemical Fingerprinting Of Tanzanian Uranium Deposits: The Insights Of Ree Ratios (La/Ce, Nd/Ce, And Sm/Nd) As A Provenance Tool, Lazaro H. Meza, John W. Kondoro, Iyabo T. Usman, Najat K. Mohammed, Titus A. Msagati, Mwingereza John Kumwenda, Mohamed S. Mazunga Dec 2025

Geochemical Fingerprinting Of Tanzanian Uranium Deposits: The Insights Of Ree Ratios (La/Ce, Nd/Ce, And Sm/Nd) As A Provenance Tool, Lazaro H. Meza, John W. Kondoro, Iyabo T. Usman, Najat K. Mohammed, Titus A. Msagati, Mwingereza John Kumwenda, Mohamed S. Mazunga

Tanzania Journal of Science

Accurate uranium provenance determination is crucial for nuclear non-proliferation and environmental protection, yet a forensic-level geochemical framework for Tanzanian uranium deposits has been lacking. This study establishes a robust analytical method using forty-five samples from three major deposits (Mkuju, Manyoni, and Bahi), analyzing elemental compositions, particularly Rare Earth Elements (REEs), via ICP-MS, and validating results using Principal Component Analysis (PCA) and Hierarchical Cluster Analysis (HCA). Despite their proximity, the deposits exhibit distinct geochemical signatures as revealed by key REE ratios and anomalies. Mkuju (mean La/Ce 1.17, Nd/Ce 0.62, Sm/Nd 0.56) is characterized by a positive Europium (Eu) anomaly and heavy …


Optimized Beamforming And Network Slicing For Dense Urban 5g Deployments, Kwame S. Ibwe Dec 2025

Optimized Beamforming And Network Slicing For Dense Urban 5g Deployments, Kwame S. Ibwe

Tanzania Journal of Science

Optimizing beamforming and network slicing is critical for enhancing spectral efficiency, energy efficiency, and resource distribution fairness in dense urban 5G networks. This paper proposes a hybrid genetic algorithm particle swarm optimization (GA-PSO) method to jointly optimize beamforming weights, bandwidth allocation, and power distribution, balancing computational efficiency with near optimal performance. The hybrid approach uses GA for global exploration and PSO for fast convergence, overcoming the limitations of standalone heuristic and exact optimization methods. Simulation experiments in a dense urban 5G network with massive MIMO base stations show that proposed method achieves up to 15% higher spectral efficiency and 18% …


Implementation Of A Carbon-Neutral Pv+Bess System - A Case Study Of Knauf Gypsum Tanzania, Santos Kihwele Dec 2025

Implementation Of A Carbon-Neutral Pv+Bess System - A Case Study Of Knauf Gypsum Tanzania, Santos Kihwele

Tanzania Journal of Science

This study presents a decarbonization pathway for Tanzania’s industrial sector by integrating a 2.966 MWp solar photovoltaic (PV) system with a 2 MW/8 MWh battery energy storage system (BESS) at KNAUF Gypsum Tanzania. A comprehensive techno- economic analysis was conducted using PVSyst simulations software. The simulation integrated site-specific meteorological data, component specifications and the factory’s electricity load profile to model annual generation patterns, system losses and battery charging and discharging cycles. The model accounted for system degradation to ensure realistic long-term performance projections. The PV+BESS solution reduces the energy-related carbon footprint to 64% and cuts annual energy costs by 65%, …


Mathematical Modeling Of Awareness-Driven Interventions For Gender-Based Violence Control In A Closed Population, Furaha M. Chuma, Edward K. Ngailo, Zubeda S. Mussa Dec 2025

Mathematical Modeling Of Awareness-Driven Interventions For Gender-Based Violence Control In A Closed Population, Furaha M. Chuma, Edward K. Ngailo, Zubeda S. Mussa

Tanzania Journal of Science

Gender-based violence (GBV) remains a critical global health issue with profound social, economic, and psychological implications. Despite concerted efforts to address this challenge, traditional intervention approaches often fall short of effectively mitigating its prevalence. In recent years, there has been growing recognition of the potential impact of awareness-based interventions in addressing various social and health crises. This paper introduces a modeling framework to explore the efficacy of awareness-based interventions in influencing the dynamics of the GBV epidemic within a closed population. A detailed sensitivity analysis, utilizing a normalized sensitivity index method, reveals that the violence transfer rate between perpetrators and …


Modelling The Impact Of Multiple Control Strategies On The Spread Of Phyllody Disease In Sesame, Augustino I. Msigwa, Furaha M. Chuma Dec 2025

Modelling The Impact Of Multiple Control Strategies On The Spread Of Phyllody Disease In Sesame, Augustino I. Msigwa, Furaha M. Chuma

Tanzania Journal of Science

Phyllody disease, caused by phytoplasma and transmitted by insect vectors such as leafhoppers, poses a serious threat to the productivity of sesame (Sesamum indicum) as it has caused substantial yield and oil-quality losses worldwide, with documented seed-yield reductions ranging from 38% to as high as 80% in severe outbreaks, particularly in Africa and India. Understanding phyllody dynamics is therefore critical to safeguard yields and trade. While some modeling efforts exist for sesame phyllody (for example, statistical and prediction-focused approaches), mechanistic transmission models (SEIR) assessing its full impact remain scarce. This study therefore develops and analyses impact of multiple control strategies …


Modeling And Forecasting Wholesale Gasoline Prices In Tanzania Using Arima And Neural Network Autoregressive Models, Thadei D. Sagamiko, Edward K. Ngailo Dec 2025

Modeling And Forecasting Wholesale Gasoline Prices In Tanzania Using Arima And Neural Network Autoregressive Models, Thadei D. Sagamiko, Edward K. Ngailo

Tanzania Journal of Science

Fluctuations in wholesale gasoline prices significantly impact the economy of import-dependent countries like Tanzania, making accurate forecasting essential for policymakers and market participants. This study forecasts monthly wholesale gasoline prices in Dar es Salaam by comparing the Autoregressive Integrated Moving Average (ARIMA) model with a Neural Network Autoregressive (NNAR) model. Using data from January 2015 to December 2024 from the Energy and Water Utilities Regulatory Authority (EWURA), the models were evaluated. The ARIMA(1,1,1) model was identified as the best-fitting linear model, but the NNAR(11,7) model demonstrated superior accuracy. On the holdout test set, the NNAR model achieved a lower Mean …


Aquifer Distribution In Lukobe Ward, Morogoro Municipality, Tanzania: Mapped Resources For Sustainable Water Access, Kelvin K. Kayuni Dec 2025

Aquifer Distribution In Lukobe Ward, Morogoro Municipality, Tanzania: Mapped Resources For Sustainable Water Access, Kelvin K. Kayuni

Tanzania Journal of Science

In response to the ongoing challenges posed by the scarcity of reliable fresh-water sources in Lukobe Ward, Morogoro Municipality, Tanzania, this study applied an integrated approach that combines geospatial and geophysical datasets to identify previously undocumented aquifers. The datasets utilized include an apparent density map generated from high-resolution GGMPlus satellite gravity data, a geological map (Quarter Degree Sheet 183), a water drainage map, and a slope map created from a digital elevation model (DEM). The analysis successfully identified four unconfined, saprolitic aquifers in the study area, designated as aquifers A, B, C, and D. These aquifers span areas of 12.2 …


Synergistic Use Of Sentinel-1 And Sentinel-2 Data For Mapping Of Degradation In Coastal Forests And Miombo Woodlands Of Tanzania, Daria C. Kimaro Dec 2025

Synergistic Use Of Sentinel-1 And Sentinel-2 Data For Mapping Of Degradation In Coastal Forests And Miombo Woodlands Of Tanzania, Daria C. Kimaro

Tanzania Journal of Science

Forest degradation is one of the leading sources of carbon emission globally. In Africa, particularly in Tanzania, forest degradation is driven by selective logging and forest fires. Monitoring degradation over large areas is very challenging due to the lack of accurate and reliable methods. This study assessed degradation in miombo woodlands and coastal forests using a synergy of remotely sensed data acquired from sentinel-1 and sentinel-2 achieved by integrating their complementary strength where sentinel-1 enhanced detection of structural changes and sentinel-2 provided spectral insight into vegetation. The 3I3D, unsupervised algorithm analysing trends for three vegetation indices (3I) in a three-dimensional …


Performance Comparison Of Kriging Models Used For Estimation Of Rainfall Variability In The Northern Coast Of Tanzania, Salma Suleiman, Clement Mromba Dec 2025

Performance Comparison Of Kriging Models Used For Estimation Of Rainfall Variability In The Northern Coast Of Tanzania, Salma Suleiman, Clement Mromba

Tanzania Journal of Science

Accurate rainfall estimation underpins effective disaster preparedness and sustainable socioeconomic planning. The performance of Ordinary Kriging (OK), Universal Kriging (UK), and Simple Kriging (SK) in estimation of rainfall variability were assessed across eight stations in the northern coast of Tanzania for the period from 1960 to 2020. Using ArcGIS 10.3, each method was evaluated and cross-validated using six performance metrics, namely; Mean Error (ME), Mean Square Error (MSE), Root Mean Square Error (RMSE), Root Mean Standardized Square Error (RMSSE), Average Standardized Error (ASE), and the Coefficient of Determination (R²). Performance comparison results indicate OK to have achieved the lowest bias, …


Simulation Based Model For Canine Distemper Virus In Prey-Predator Dynamics, Mussa A. Stephano Dec 2025

Simulation Based Model For Canine Distemper Virus In Prey-Predator Dynamics, Mussa A. Stephano

Tanzania Journal of Science

This study investigates the dynamic interactions of a prey-predator ecosystem infected with Canine Distemper Virus (CDV), focusing on predation and disease transmission. A deterministic model, coupled with Monte Carlo simulations (MCS), employed to capture both stochastic variability and environmental fluctuations. The findings indicate that classical prey-predator cycles provide the baseline for population dynamics, but the introduction of CDV and environmental noise fundamentally alters system behavior. Initially, populations exhibit oscillations that gradually stabilize into dynamic equilibria. However, the disease persists within both prey and predator populations, suggesting endemicity rather than extinction. Predation plays a dual role in disease dynamics, while it …


Variations In Physicochemical Properties, Microbiological Profiles, And Nutrient Dynamics In The Temi River, Arusha, Tanzania: Sources And Implications, Aldo J. Kitalika Dec 2025

Variations In Physicochemical Properties, Microbiological Profiles, And Nutrient Dynamics In The Temi River, Arusha, Tanzania: Sources And Implications, Aldo J. Kitalika

Tanzania Journal of Science

This study thoroughly investigates the physicochemical properties, microbiological profiles, and nutrient dynamics of the Temi River in Tanzania. The sources and implications of fluctuations in dissolved organic carbon (DOC) and nutrients during the wet and dry seasons are carefully analysed. Water samples were collected from various geographically referenced points along the river, and analyses were performed using the APHA Standard Methods for Water and Wastewater Testing. The results show that most parameters increased downstream in both seasons, with the highest DOC levels reaching 352.11 mg/L in the wet season, followed by a significant decrease to 126.00 mg/L during the dry …


A Comparative Analysis Of Complete Streets And Multimodal Transport Approaches: Implications For Sustainable Urban Mobility In Lincoln, And Global Contexts, Oliva Richard Kilyenyi Dec 2025

A Comparative Analysis Of Complete Streets And Multimodal Transport Approaches: Implications For Sustainable Urban Mobility In Lincoln, And Global Contexts, Oliva Richard Kilyenyi

Department of Civil and Environmental Engineering: Dissertations, Theses, and Student Research

Movement of people and goods in urban areas through different modes of transportation including walking, cycling, public transit and by autos is termed as urban mobility. Urban mobility presents significant environmental, social, and economic challenges for cities worldwide as they grapple with the impacts of conventional transportation systems, particularly in North America context where car-centric planning approaches has dominated urban developments since 1950s. Car-centric dominance is 80% in North American Metropolitan areas (Manaugh et al., 2015). The impacts of these conventional systems include greenhouse gas emission emissions contributing approximately 24% of global carbon dioxide (CO2) emissions, air pollution …


The Role Of Marine Spatial Planning (Msp) In Managing Conflicts Between Marine Resource Users In Tanzania, Ramadhani Juma Shausi Nov 2025

The Role Of Marine Spatial Planning (Msp) In Managing Conflicts Between Marine Resource Users In Tanzania, Ramadhani Juma Shausi

World Maritime University Dissertations

No abstract provided.


Fahp-Topsis Model In Ranking Critical Success Factors Of E-Learning: A Comparative Analysis Of Normalization Methods, Judith R. Pande, David Koloseni, Septimi Kitta Oct 2025

Fahp-Topsis Model In Ranking Critical Success Factors Of E-Learning: A Comparative Analysis Of Normalization Methods, Judith R. Pande, David Koloseni, Septimi Kitta

Tanzania Journal of Science

The teaching and learning process has become effective and explicit due to the progressive development of e-learning. This has significantly transformed the education framework. As a result, evaluating the usefulness of e-learning requires a detailed understanding of the critical success factors that impact the success of e-learning environments. This study ranked these factors using Multi-Criteria Decision-Making techniques. Specifically, the Fuzzy Analytical Hierarchy Process was used to determine the weight of each factor, while the Technique for Order of Preference by Similarity to Ideal Solution was used to rank the factors of e-learning. The study also examined and compared four normalization …


Assessment Of Tumour Control Probability And Equivalent Uniform Dose In Conventional 3d-Crt Vs. Hypo-Fractionated Imrt, Jumaa D. Kisukari, Mwingereza J. Kumwenda, Khamis O. Amour, Ehab M. Attalla, Emmanuel Lugina Oct 2025

Assessment Of Tumour Control Probability And Equivalent Uniform Dose In Conventional 3d-Crt Vs. Hypo-Fractionated Imrt, Jumaa D. Kisukari, Mwingereza J. Kumwenda, Khamis O. Amour, Ehab M. Attalla, Emmanuel Lugina

Tanzania Journal of Science

Hypo-fractionated (HF) radiotherapy offers a promising solution to improve access to cancer treatment in resource-limited settings, such as developing countries, by reducing the number of treatment sessions compared to conventional fractionation (CF). For effective implementation, evaluating Equivalent Uniform Dose (EUD) and Tumour Control Probability (TCP) is essential to ensure treatment efficacy across different radiotherapy techniques. This study compares treatment plans generated using Three-Dimensional Conformal Radiation Therapy with Conventional Fractionation (3D-CRT CF) and Intensity Modulated Radiation Therapy with Hypo-fractionation (IMRT HF) in patients with localized prostate cancer. A total of 50 patients were CT-simulated, and their images were imported into a …


A Comparative Study For Classical Machine Learning Models For Swahili Social Media Sentiment Analysis, Mahadia Tunga, Davis David Oct 2025

A Comparative Study For Classical Machine Learning Models For Swahili Social Media Sentiment Analysis, Mahadia Tunga, Davis David

Tanzania Journal of Science

Despite sentiment analysis being one of the most popular applications in Natural Language Processing (NLP), most studies are skewed towards languages with a rich corpus (language database). Less emphasis has been placed on low-resource languages like Swahili. Swahili is the official language of the African Union and of 4 countries in East Africa, and is spoken by many people on the African continent. This study performed sentiment analysis using 3,000 tweets hosted on the Zindi Africa platform. Data was processed using a term frequency-inverse document frequency vectorization method, and five classical machine learning algorithms (RandomForest, XgBoost, and CatBoost, HistogramGradientBoost, LightGradientBoos) …


Evaluating Weather Research And Forecasting Model In Simulating March-May Rainfall In Tanzania: Implications Of Selecting Parameterization Schemes, Mohamed H. Mohamed, Makungu James Ng'oga Oct 2025

Evaluating Weather Research And Forecasting Model In Simulating March-May Rainfall In Tanzania: Implications Of Selecting Parameterization Schemes, Mohamed H. Mohamed, Makungu James Ng'oga

Tanzania Journal of Science

The current study evaluates the performance of the Weather Research and Forecasting (WRF) model in simulating seasonal rains of March-May (MAM) in Tanzania, based on the implication of selecting parameterization scheme combinations. The model was configured into two domains with horizontal resolutions of 36 km and 12 km and the initial and lateral boundary conditions were provided by the Climate Forecast System Version 2 at 00 UTC. However, only the inner domain of 12 km was used for analysis, which has a fine horizontal resolution that accounts for small scale features such as terrains. Twelve simulations have been performed using …


Mathematical Analysis Of Toxicants And Diseases Impact On A Prey-Predator System With Control Interventions, Nuru Yazidi Juma, Thadei Damas Sagamiko, James Philbert Mpele Oct 2025

Mathematical Analysis Of Toxicants And Diseases Impact On A Prey-Predator System With Control Interventions, Nuru Yazidi Juma, Thadei Damas Sagamiko, James Philbert Mpele

Tanzania Journal of Science

This study developed a generic prey-predator mathematical model incorporating logistic growth for prey and a Holling Type I functional response for predator consumption. Prey-predator interactions form the foundation of ecological balance, but in recent decades these systems have been increasingly threatened by toxicants and infectious diseases. The combined effect of these challenges can lead to severe population declines, biodiversity loss, and ecosystem instability, making their study important for conservation and environmental management. The model includes the effects of diseases and toxicants on prey and toxicants only on predators, and explores optimal control strategies to mitigate these threats. Without considering time …


Design Of High-Performance Synchronous Reluctance Motor For Hybrid Electric Vehicle Application, Fred Loita, Jackson Justo Oct 2025

Design Of High-Performance Synchronous Reluctance Motor For Hybrid Electric Vehicle Application, Fred Loita, Jackson Justo

Tanzania Journal of Science

This paper presents the simulation-based design of a synchronous reluctance motor (SynRM) coupled electromechanical system suitable for the hybrid electric vehicle. The study considers SynRM with a 75kW power rating with the capability to produce up to 125kW maximum power for the electric vehicle. The focus is mainly on rotor and stator design; the angles of the flux-barrier ends are considered to reduce the torque ripple due to the slot harmonics. Reluctance machines are indeed competitive for applications requiring high efficiency at low cost. However, it is a challenging task to find design solutions that ensure structural integrity of the …


Rainwater Harvesting For Domestic Use In Suburb Areas Of Dar Es Salaam, Tanzania: A Case Study Of Wazo Hill, Scholastica S. Ishengoma, Mahir Mohammed Said, Neema O. Msuya Oct 2025

Rainwater Harvesting For Domestic Use In Suburb Areas Of Dar Es Salaam, Tanzania: A Case Study Of Wazo Hill, Scholastica S. Ishengoma, Mahir Mohammed Said, Neema O. Msuya

Tanzania Journal of Science

Despite the increasing reliance of rainwater harvesting in semi-urban areas, there is a lack of comprehensive localized data on the safety of harvested rainwater, particularly in areas such as Wazo Hill where communities predominantly depend on it. This study evaluates the quality of harvested rooftop rainwater intended for human consumption and assesses its compliance with the World health Organization (WHO) and Draft East Africa Standards (DEAS) for drinking water. Rainwater samples were collected from various catchment surfaces and storage systems located in Wazo Hill, Tanzania. A stratified random sampling technique was employed to select the households equipped with rainwater harvesting …


Assessment Of Bacteriological Quality And Physico-Chemical Parameters Of Domestic Water Sources In Relation To Human Health Risk In Kigamboni, Tanzania, Joseph A. Mwakosya Oct 2025

Assessment Of Bacteriological Quality And Physico-Chemical Parameters Of Domestic Water Sources In Relation To Human Health Risk In Kigamboni, Tanzania, Joseph A. Mwakosya

Tanzania Journal of Science

Data on bacteriological quality and physico-chemical parameters is crucial for protection and sustainable utilization of water resources. This study determined bacteriological quality and physico-chemical parameters of well and tap water sourcesin relation to human health risk in Kigamboni, Tanzania. Thirty water samples were collected randomly and analyzed using SPSS software. The mean values for well water samples of pH, electrical conductivity (EC), total dissolved solids (TDS), turbidity, Chloride, Sulphate, Nitrate, Phosphate, and Calcium Carbonate were 7.2, 960.27 mg/L, 528.13 mg/L, 1.52 NTU, 288.00 mg/L, 30.13 mg/L, 0.05 mg/L, 0.08 mg/L, and 160.07 mg/L, respectively. The mean values for tap water …


Comparative Study On The Application Of Gra, Psi And Hybrid Psi-Gra Techniques For Optimising Turning Parameters In Multi-Criteria Problems, Mussa Iddi Mgwatu Oct 2025

Comparative Study On The Application Of Gra, Psi And Hybrid Psi-Gra Techniques For Optimising Turning Parameters In Multi-Criteria Problems, Mussa Iddi Mgwatu

Tanzania Journal of Science

The optimum turning parameters help to justify the investment in machine tools for manufacturing industries. However, solving optimisation models to achieve optimum turning parameters in multi-criteria environment is complex leading to the application of multi-criteria decision-making techniques. This paper compares three multi-criteria decision-making techniques in determining optimum turning process parameters namely spindle speed, feed rate and depth of cut. The performance criteria are material removal rate, consumed electrical energy and tool wear rate. Example data for turning process were obtained from other studies while the analyses for multi-criteria decision-making were performed using grey relational analysis (GRA), preference selection index (PSI) …


Heavy Metal Contamination And Health Risks In Katoro's Artisanal Gold Mining Soils, Tanzania, Innocent J. Lugendo, Venance Mwesiga Oct 2025

Heavy Metal Contamination And Health Risks In Katoro's Artisanal Gold Mining Soils, Tanzania, Innocent J. Lugendo, Venance Mwesiga

Tanzania Journal of Science

This study assessed heavy metal contamination in surface soils from artisanal gold mining areas in Katoro, Tanzania, evaluating ecological and human health risks. Thirty-six soil samples were systematically collected from three mining villages (Bingwa, Isenye, and CCM) at varying distances ranging from 30 to 90 m from active mining pits alongside twelve control samples from a non-mining area for comparison purposes. Concentrations of Cr, Cu, Ni, Zn, Pb, and As in soil samples were analyzed using energy-dispersive X-ray fluorescence spectrometry (EDXRF). Results revealed severe contamination, with Cr (117–1255 mg/kg), Cu (81–104 mg/kg), and Ni (89–271 mg/kg) exceeding permissible limits. The …


Spatio-Temporal Dynamics Of The Onset And Cessation Of Ond Rainy Season Across Bimodal Regions Of Tanzania, Rajabu J. Mangara, Paul Ts Limbu Oct 2025

Spatio-Temporal Dynamics Of The Onset And Cessation Of Ond Rainy Season Across Bimodal Regions Of Tanzania, Rajabu J. Mangara, Paul Ts Limbu

Tanzania Journal of Science

This study investigates the temporal variability of the onset, cessation, and duration of the October-November-December (OND) rainy season in the bimodal rainfall region of Tanzania. Utilizing daily precipitation data from the Multi-Source Weighted-Ensemble Precipitation dataset for the period 2014–2023, the study employs the Accumulated Daily Index method to determine the onset and cessation of rains, with the seasonal duration computed as the difference between these dates. Variability in onset, cessation, and season length was quantified using the Coefficient of Variation. The findings highlight significant spatial variability in onset, with early rains in northwestern areas (e.g., Bukoba) and coastal zones, commencing …


Comparative Evaluation Of Dicyclohexylamine And N-Methyldiethanolamine As Corrosion Inhibitors For Top Of Line Corrosion On Api X80 Carbon Steel In Saturated Carbon Dioxide Aqueous Solutions, Frida W. Andalu, Abraham K. Temu, Alfred R. Akisanya, Joseph Yn Philip Oct 2025

Comparative Evaluation Of Dicyclohexylamine And N-Methyldiethanolamine As Corrosion Inhibitors For Top Of Line Corrosion On Api X80 Carbon Steel In Saturated Carbon Dioxide Aqueous Solutions, Frida W. Andalu, Abraham K. Temu, Alfred R. Akisanya, Joseph Yn Philip

Tanzania Journal of Science

This work has evaluated the efficiency of selected volatile corrosion inhibitors in mitigation of top of line corrosion in wet gas pipeline at different temperatures. The main challenge of top of line corrosion in carbon dioxide rich environment is the ability of the volatile corrosion inhibitor to effectively mitigate corrosion at adverse conditions. Electrochemical corrosion experiments using potentiodynamic polarization method were conducted at temperatures of 20 ℃, 35 ℃ and 45 °C to evaluate the efficiency of dicyclohexylamine and n-methyldiethanolamine corrosion inhibitors for top of line corrosion inhibition on carbon steel specimens derived from API X80 natural gas pipelines. The …


Energy-Saving Simple Adaptive Recursive Terminal Sliding Mode Control For Industrial Feed Drive Systems, Haryson Johanes Nyobuya Oct 2025

Energy-Saving Simple Adaptive Recursive Terminal Sliding Mode Control For Industrial Feed Drive Systems, Haryson Johanes Nyobuya

Tanzania Journal of Science

This paper proposes a simple adaptive recursive terminal sliding mode control approach for industrial feed drive systems. The design employs a recursive sliding mode structure that eliminates the reaching phase and ensures finite-time convergence of the tracking error. To mitigate chattering, a second-order nonsingular terminal sliding mode is used and the parameters to compensate for disturbances are obtain in terms of integral form and a proportional terminal term, which enhances disturbance rejection and further guarantees finite-time convergence. The proposed controller significantly reduces the tracking error and saves energy for the feed drive system. Numerical simulations on an industrial feed drive …


Nickel (Ii) Complex Decorated Zinc-Cadmium Sulfide Type-Ii Heterojunction For Enhanced Photocatalytic Hydrogen Production, Miza Kombo, Abdul Muhamed, Suleiman Suleiman, An-Wu Xu Oct 2025

Nickel (Ii) Complex Decorated Zinc-Cadmium Sulfide Type-Ii Heterojunction For Enhanced Photocatalytic Hydrogen Production, Miza Kombo, Abdul Muhamed, Suleiman Suleiman, An-Wu Xu

Tanzania Journal of Science

The binary metal sulfide Zn0.5Cd0.5S has emerged as a promising photocatalyst for hydrogen (H2) production via visible-light-driven water splitting. However, its practical application is limited by rapid charge carrier recombination and insufficient stability. In this study, nickel (II)-(3-pyridyl) benzimidazole (NPBIm) complexes were synthesized and employed an ultrasonic-assisted method to decorate the surface of Zn0.5Cd0.5S, forming a novel metal-complex semiconductor heterostructure system (Zn0.5Cd0.5S/NPBIm). This hybrid system significantly enhances photocatalytic H2 evolution under visible light irradiation. Experimental findings reveal that the incorporation of NPBIm molecules improves the …