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Mineralogy And Geochemistry Of The Asanje Iron Ore Deposit Within The Mayamaya-Hombolo Belt, Dodoma Region, Central Tanzania, Yusto J. Shine, Michael M. Msabi, Jagarlamudi Seetharamaiah Sep 2022

Mineralogy And Geochemistry Of The Asanje Iron Ore Deposit Within The Mayamaya-Hombolo Belt, Dodoma Region, Central Tanzania, Yusto J. Shine, Michael M. Msabi, Jagarlamudi Seetharamaiah

Tanzania Journal of Science

This paper presents the mineralogy and chemical composition including iron ore impurities to ascertain its suitability for industrial applications. The Asanje iron ore deposit is hosted in Precambrian volcano-sedimentary rocks in the Mayamaya-Hombolo Belt in Dodoma region, within the Lake Nyanza Superterrane. Iron ores are found in two parallel ridges trending NW-SE. Ridge I occurs as vein and banded hematite-type ore and Ridge II as massive-type ore. A total of 24 ore samples were analysed for major and trace elements by XRF and petrographic studies by optical microscopy and XRD. The XRD results revealed that hematite and goethite are the …


Modelling The Impacts Of Immigrants On Covid 19 Transmission Dynamics With Control Measures, Alfred K. Hugo, Goodluck M. Mlay, Moses B. Kabigi Sep 2022

Modelling The Impacts Of Immigrants On Covid 19 Transmission Dynamics With Control Measures, Alfred K. Hugo, Goodluck M. Mlay, Moses B. Kabigi

Tanzania Journal of Science

The COVID-19 pandemic began in Wuhan City in the Hubei province of China in December 2019. The disease spread quickly in many countries around the world due to mobility of people from one location to another. As a result, a COVID-19 mathematical model with the impacts on immigrants was proposed to study its transmission dynamics and possible control measures. The reproduction number was determined by using the next-generation technique and found to be 0.636, indicating that the transmission could be minimized in the community if all immigrants were effectively controlled. The Pontryagin's Maximum Principle was applied in analysing control strategies …


Dynamical Analysis And Control Strategies For Capturing The Spread Of Covid-19, Mutairu K. Kolawole, Kazeem A. Odeyemi, Adedapo I. Alaje, Asimuyu O. Oladapo, Kehinde A. Bashiru Sep 2022

Dynamical Analysis And Control Strategies For Capturing The Spread Of Covid-19, Mutairu K. Kolawole, Kazeem A. Odeyemi, Adedapo I. Alaje, Asimuyu O. Oladapo, Kehinde A. Bashiru

Tanzania Journal of Science

In this paper, a study of preventive measures capable of curbing the spread of COVID 19 pandemic to avoid its second wave was carried out. The existence and uniqueness of the proposed mathematical model is assured, the basic reproduction number is established, the local and global stability of the disease free equilibrium are well obtained and the variational iteration method is applied to solve the mathematical model. Numerical simulation of the included control parameters are carried out. The obtained results and outcomes are presented graphically. It was revealed that enlightenment to vaccination awareness should be encouraged as vaccination is a …


Evaluation Of Enzymatic Activity During Growth Of Pleurotus Hk 37 On Saba Comorensis Exocarp, Isse I. Molobele, Rose J. Masalu, Prosper R. Mosha, Cyprian B. Mpinda Sep 2022

Evaluation Of Enzymatic Activity During Growth Of Pleurotus Hk 37 On Saba Comorensis Exocarp, Isse I. Molobele, Rose J. Masalu, Prosper R. Mosha, Cyprian B. Mpinda

Tanzania Journal of Science

Mushrooms degrade lignocellulosic biomass by releasing lignolytic and hydrolytic enzymes which convert lignocellulosic material into soluble and low molecular weight compounds which are then absorbed as nutrients. In the present study, enzymatic activities of Pleurotus HK 37 during growth on Saba comorensis exocarps were evaluated. It was observed that, Pleurotus HK 37 has ability to produce lignolytic enzyme (Laccase) and hydrolytic enzymes (Carboxymethyl cellulase, xylanase and filterpaperase). Maximum laccase activity of 3.33 ± 0 UmL-1 was observed during colonization period and the activity dropped during fruitification phase. Similar to hydrolytic enzymes, the activity was observed during colonization period and decreased …


Effects Of Small-Scale Mining Activities On Fisheries And Livelihoods In The Birim River In Atiwa District, Eastern Region Of Ghana, Elliot Haruna Alhassan, Samuel Opoku Dandi, Sandra Akugpoka Atindana Sep 2022

Effects Of Small-Scale Mining Activities On Fisheries And Livelihoods In The Birim River In Atiwa District, Eastern Region Of Ghana, Elliot Haruna Alhassan, Samuel Opoku Dandi, Sandra Akugpoka Atindana

Tanzania Journal of Science

The socioeconomic importance of small-scale mining in Ghana is of great interest to the country. It provides employment, supports the livelihood of poor rural areas, and also contributes to national income. Despite all these importance, it has a great influence on the surroundings, with surface and groundwater bodies being the most affected. The study was conducted to determine the effects of small-scale mining activities on fisheries and livelihoods along the Birim River in Atiwa District of Ghana, and also, to ascertain the nature of mining in the catchment and the current status of fisheries in the river. Data were collected …


A Decade Review Of Disease Surveillance Research Trends In The International Journal Of Health Geographics (2009 To 2018), Rose Jimenez, Paradorn Wongchanapai Aug 2022

A Decade Review Of Disease Surveillance Research Trends In The International Journal Of Health Geographics (2009 To 2018), Rose Jimenez, Paradorn Wongchanapai

Publications and Research

The field of health geographics is rapidly growing in its methods and epistemologies. This is a review of the open-source journal International Journal of Health Geographics, and the trends in disease surveillance over ten years (2009-2018). Drawing from research review methodologies, we wrote a Python script to quantify research trends within the field of geographic disease surveillance, finding many articles focusing on population health, techniques of GIS, qualitative techniques, and geospatial technology for health monitoring. This was foundational in conducting an in-depth qualitative lexical analysis of article content and epistemologies. Overall, we concluded that over the time period, the …


28 Ghz Patch Antenna Array With Reduced Mutual Coupling For 5g Communications Systems, Rahabu F. Mwang’Amba, Hashimu Uledi Iddi Aug 2022

28 Ghz Patch Antenna Array With Reduced Mutual Coupling For 5g Communications Systems, Rahabu F. Mwang’Amba, Hashimu Uledi Iddi

Tanzania Journal of Engineering and Technology (TJET)

A 28 GHz patch antenna array with reduced mutual coupling for 5G communication systems is presented in this paper. Two elements antenna array was simulated with a periodic boundary to represent an infinity array. The antenna array is attached with a pair of the coupled directional coupler with a coupling value of -3.47 dB, and transmission lengths of 3.40 mm and 7.62 mm depending on the antenna array's magnitude and phase coefficient were designed and simulated. A reduced mutual coupling of -31.86 dB compared to -10.75 dB for an array without a decoupling network was observed. The wide scanning angle …


Machine Learning Approach For Classifying Power Outage In Secondary Electric Distribution Network, Stephan Mgaya, Hellen Maziku Jul 2022

Machine Learning Approach For Classifying Power Outage In Secondary Electric Distribution Network, Stephan Mgaya, Hellen Maziku

Tanzania Journal of Engineering and Technology (TJET)

Power outage is the problem that hinders social and economic development especially for developing countries like Tanzania. Frequent power outages damage electric equipment, and negatively affect the industrial production process. Power outages cannot be completely eradicated due to uncontrolled cause like natural calamities but technical challenges can be managed and hence reducing power outages. The existing manual methods used to locate power outage like customer calls is inefficient and time consuming. On the other hand, modern method like the Advanced Metering Infrastructure (AMI) still faces a challenge in effectively classifying power line outage due to the nature of imbalanced datasets. …


Big Data Analytics Framework For Effective Higher Education Institutions, George Matto Jul 2022

Big Data Analytics Framework For Effective Higher Education Institutions, George Matto

Tanzania Journal of Engineering and Technology (TJET)

There has been an increased dependency on Information and Communication Technologies (ICTs) in undertaking various activities in Higher Education Institutions (HEIs) ecosystems. Because of that, huge volumes of data have increasingly been generated. There have been, for instance, considerable amounts of data generated through electronic platforms involved in students’ admission and registration process, students’ academic records management, teaching and learning data, curriculum related data, and several other administrative data. Analysis of data generated from these platforms stands to give students, lecturers, HEIs Management, policy makers and implementers, and other stakeholders useful insights that would help in improving HEIs’ effectiveness. Unfortunately, …


An Iot Based Worker Safety Helmet Using Cloud Computing Technology, Yuthriya Iddi Khamis, Mahmoud Alawi, Waheed Muhammad Sanya Jul 2022

An Iot Based Worker Safety Helmet Using Cloud Computing Technology, Yuthriya Iddi Khamis, Mahmoud Alawi, Waheed Muhammad Sanya

Tanzania Journal of Engineering and Technology (TJET)

Miner safety and security is a major challenge around the world due to the exposure to toxic gases that are frequently released in underground mines. Miners' health is adversely affected primarily by toxic gases, which endanger the workers' lives. Furthermore, human sensory abilities do not detect these dangerous gases. As a result, this paper proposes a safety monitoring system that includes a temperature sensor, humidity sensor, and gas sensors to detect harmful gases and alert miners to those harmful gases using the smart helmet they wear. These gases are transmitted to the control station via the cloud using Internet of …


Group-Based Data Offloading Techniques Assisted By D2d Communication In 5g Mobile Network, Juma S Ally Jun 2022

Group-Based Data Offloading Techniques Assisted By D2d Communication In 5g Mobile Network, Juma S Ally

Tanzania Journal of Engineering and Technology (TJET)

Machine type communication devices proposed as one of the substantial data collections in the 5G of wireless networks. However, the existing mobile communication network is not designed to handle massive access from the MTC devices instead of human type communication. In this context, we propose the device-to-device communication assisted a mobile terminal (smartphone) on data computing, focusing on data generated from a correlated source of machine type communication devices. We consider the scenario that the MTC devices after collecting the data will transmit to a smartphone for computing. With the limitation of computing resources at the smartphone, some data are …


Real-Time Data Analytics For Monitoring Electricity Consumption Using Iot Technology, Waheed Muhammad Sanya, Gaurav Bajpai, Omar Haji Kombo, Evariste Twahirwa Jun 2022

Real-Time Data Analytics For Monitoring Electricity Consumption Using Iot Technology, Waheed Muhammad Sanya, Gaurav Bajpai, Omar Haji Kombo, Evariste Twahirwa

Tanzania Journal of Engineering and Technology (TJET)

Rising electricity bills as a result of climate variability and new home electrical and electronic appliances are becoming a major source of concern for most end users. Consumers are typically unaware of their household electricity consumption patterns and the costs associated with them, making proper planning and budgeting difficult. Monitoring and controlling energy consumption on appliances can reduce energy costs for end-users. The Internet of Things (IoT) has the potential to provide remote monitoring and control of devices via automated monitoring and control. In this study, we propose an IoT-enabled system for monitoring and controlling energy consumption in homes to …


Digital Skills And Self-Employment Among Graduates Of Technical Higher Education Institutions In Tanzania, Charles Raphael Jun 2022

Digital Skills And Self-Employment Among Graduates Of Technical Higher Education Institutions In Tanzania, Charles Raphael

Tanzania Journal of Engineering and Technology (TJET)

Digital skills are the driving forces for innovative, inclusive and sustainable growth through innovations and digitalization which in turn stimulate job creation, alleviate poverty, reducing inequality, facilitating the delivery of goods and services. However, large number of graduates is shown to be weak in digital skills in the industry hence affect their employability including self-employment. Recently, the Technical Higher Education Institutions (THEIs) took some initiatives to instill the digital skills to their respective students. This study therefore assessed the level of competence of digital skills among graduates following the initiatives taken by the THEIs and their influence on self-employment. It …


Implementation Of Digital Transformation In The Technical Higher Education Institutions In Tanzania, Charles Raphael Jun 2022

Implementation Of Digital Transformation In The Technical Higher Education Institutions In Tanzania, Charles Raphael

Tanzania Journal of Engineering and Technology (TJET)

Digital transformation has been prioritized recently in this era of fourth industrial revolution by various organizations for maintaining strong competitive advantage, especially in the fourth industrial revolution. The higher education institutions must likewise adopt and implement digital transformation to enrich their students with the knowledge, experience and the skills they need for a very different future. Technical higher education institutions are inevitable in the given transformation. However, very little is known regarding adoption of digital transformation in the given institutions. This study therefore examined the level of adoption of digital services in the technical higher education institutions in Tanzania. It …


Efficient And Simple Heuristic Algorithm For Portfolio Optimization Collether John, Collether John Jun 2022

Efficient And Simple Heuristic Algorithm For Portfolio Optimization Collether John, Collether John

Tanzania Journal of Engineering and Technology (TJET)

Markowitz model considers what is termed as standard portfolio optimization. The portfolio optimization problem is a problem which based on asset allocation and diversification for maximum return with minimum risk. Thus, the standard portfolio optimization problem happens when the constraints considered are budget and no-short selling. In reality however, portfolio optimization has realistic constraints to be incorporated such as holding sizes, cardinality and transaction cost. When realistic constraints are added into portfolio optimization problem, it becomes too complex to be solved by standard optimization methods which in this case turns to be an extended portfolio optimization problem. Markowitz solution and …


Analyzing The Influence Of Smart-Device Visual Features, Viewing Distance And Content Factors On Video Streaming Qoe, Alex Frank Mongi Jun 2022

Analyzing The Influence Of Smart-Device Visual Features, Viewing Distance And Content Factors On Video Streaming Qoe, Alex Frank Mongi

Tanzania Journal of Engineering and Technology (TJET)

Quality of experience (QoE) over wireless networks has attracted attention from industry and academia due to an increase in video streaming applications. Several researchers have attempted to understand the factors affecting QoE and design appropriate quality control strategies. Normally, video streaming is initiated by a user who accesses video content over a network using a smart device that may be held at various viewing distances. Each aforementioned factor has the potential to affect QoE. However, several studies explore the behavior of wireless networks on video streaming QoE. To understand the effects of other factors on QoE, this paper investigates the …


Cyber Security Challenges, Its Emerging Trends On Latest Information And Communication Technology And Cyber Crime In Mobile Money Transaction Services, Hakeem J. Pallangyo Jun 2022

Cyber Security Challenges, Its Emerging Trends On Latest Information And Communication Technology And Cyber Crime In Mobile Money Transaction Services, Hakeem J. Pallangyo

Tanzania Journal of Engineering and Technology (TJET)

This paper investigates the challenges emerging trends on latest Information and Communication Technology and cybercrime in mobile money transaction services in Tanzania. The objective of this is to evaluate the challenges associated with this rapid growth in ICT and to determine factors influencing Cybersecurity readiness and Cybercrimes in mobile money transaction services. Cyber Security plays a significant role in the field of Information and Communication Technology especially on mobile money transaction services. The study recognizes the provision of mobile money services by both telecommunication companies and local banks, the fact is that whenever we think about the cyber security, the …


Evaluation Of Natural Radioactivity And Radiation Hazards Of Soils Around Petroleum Products Marketing Company Using Gamma Ray Spectrometry, Dayo A. Ayeni, Festus M. Adebiyi Jun 2022

Evaluation Of Natural Radioactivity And Radiation Hazards Of Soils Around Petroleum Products Marketing Company Using Gamma Ray Spectrometry, Dayo A. Ayeni, Festus M. Adebiyi

Tanzania Journal of Science

This study aimed at evaluating natural radioactivity and radiation hazards of soils around a petroleum product marketing company due to anthropogenic influences using gamma ray spectrometry. Top soils (5 cm deep) were collected from diverse locations inside the premises of the Company using standard analytical technique, while control samples were acquired at approximately 200 m from the study area. Mean activity concentrations of the radionuclides in the test soils were 89.36 Bq/kg for 40K, 92.1 Bq/kg for 238U and 10.95 Bq/kg for 232Th, which are more than that of control samples with statistically significant differences. Assessment of the radiological levels …


Factors Influencing The Choice Of Place Of Delivery Of A First Child Among Nigerian Women, Olakiitan I Adeniyi, Nathanael B Afolabi, Adesupo A Akinrefon, Ifeyinwa V Omekam, Ifeoluwa R Olonijolu Jun 2022

Factors Influencing The Choice Of Place Of Delivery Of A First Child Among Nigerian Women, Olakiitan I Adeniyi, Nathanael B Afolabi, Adesupo A Akinrefon, Ifeyinwa V Omekam, Ifeoluwa R Olonijolu

Tanzania Journal of Science

Among the factors responsible for maternal deaths in developing countries is complications during pregnancy and childbirth, and as such, the choice of place for delivery is vital as the quality of attention received can either aid or reduce the risks attached to child bearing. This study seeks to statistically model factors that determine the place of delivery in Nigeria among women of reproductive age taking into consideration possible nesting structure in the mode of data collection. A two-level hierarchical multilevel logistic model with the individual women as the lower level and the state of residence as the second level was …


Modelling Internet Traffic Streams With Ga/M/1/K Queuing Systems Under Self-Similarity, Jumoke Popoola, Olusogo J Popoola, Oyebayo R Olaniran Jun 2022

Modelling Internet Traffic Streams With Ga/M/1/K Queuing Systems Under Self-Similarity, Jumoke Popoola, Olusogo J Popoola, Oyebayo R Olaniran

Tanzania Journal of Science

High-intensity concurrent arrivals of request packets in Internet traffic can cause dependence of event-to-event-times of the requests being served, which causes non-memoryless, modelled with heavy-tail distributions unlike common known traffics. The performance of Internet traffic can be examined using analytical models for the purpose of optimizing the system to reduce its operating costs. Therefore, our study examined a Ga/M/1/K Internet queue class (Gamma arrival processes, Ga; with memoryless-Poisson service process, M; a single server, 1, and K waiting room) and proposed specific derivations of its performance indicators. Real-life data of a corporate organisation Internet server was monitored at both peak …


A Mathematical Model And Sensitivity Analysis Of Lassa Fever With Relapse And Reinfection Rate, Latifat M Erinle-Ibrahim, Olukayode Adebimpe, Waheed O Lawal, Joshua O Agbomola Jun 2022

A Mathematical Model And Sensitivity Analysis Of Lassa Fever With Relapse And Reinfection Rate, Latifat M Erinle-Ibrahim, Olukayode Adebimpe, Waheed O Lawal, Joshua O Agbomola

Tanzania Journal of Science

In this research paper, we depict an unprecedented four-dimensional ordinary differential equation modeling the dynamic transmission of the Lassa fever virus incorporating relapse and reinfection rate. Recent studies showed that the recovered individuals from Lassa fever can again be susceptible; which contradicted the common assumptions made by different researchers on modeling of Lassa fever. So, this article corrects and states the implications of the assumptions on the population density. The numerical simulations unveil the effect of relapse, reinfection, and treatment rate in the affected population. Performing sensitivity analysis suggests all new incorporated parameters can impact the infection dynamics substantially. The …


Effects Of Feed Moisture Content, Soybean Ratio And Barrel Temperature On Physical And Functional Properties Of Extruded Maize-Soybean Flour Blends, Robert Mugabi, Stellah Byakika, Ivan Muzira Mukisa Jun 2022

Effects Of Feed Moisture Content, Soybean Ratio And Barrel Temperature On Physical And Functional Properties Of Extruded Maize-Soybean Flour Blends, Robert Mugabi, Stellah Byakika, Ivan Muzira Mukisa

Tanzania Journal of Science

The effects moisture content, temperature and soybean ratio on expanded product characteristics of extruded maize-soybean blends were studied. Response surface methodology was used to study the effects of extrusion conditions on extrudate properties taking barrel temperature (BT), feed moisture content (FM) and soybean flour ratio (SR) as factors. Expansion ratio (ER), water absorption index (WAI), water solubility index (WSI), hardness and colour (b* - (+) yellowness) of the extrudates were determined. BT and FM had significant effects on ER (p < 0.05). At low FM levels, ER increased with BT. It was observed that both FM and BT significantly affected WAI and WSI. WAI increased as FM increased. Increasing FM to 20% resulted in a decrease in WSI, beyond which an increase was observed. Hardness increased significantly as feed moisture content increased. High SR content significantly increased the extrudate hardness. FM had no significant effect on colour. Colour increased as the SR and BT increased. Significant regression models explained the effects of SR, FM, and BT on all response variables. All of the response variables' R2, were higher than 0.89. Keywords: Maize, Soybean, moisture content, extrusion


Mathematical Model Of Covid-19 Transmission Dynamics With Double Dose Vaccination, Tawakalt A Ayoola, Mutairu K Kolawole, Amos O Popoola Jun 2022

Mathematical Model Of Covid-19 Transmission Dynamics With Double Dose Vaccination, Tawakalt A Ayoola, Mutairu K Kolawole, Amos O Popoola

Tanzania Journal of Science

This research attempted to investigate the effects of double dose vaccination in a non-linear mathematical model of Covid-19 infections with special compartments class termed first and second dose vaccination. The basic reproduction number was obtained, the stability of the model was analyzed, and the sensitivity analysis was also carried out. Of interest is the numerical simulation of the model where the impacts of contact rate, first and second dose vaccination were studied. The obtained results recommended how to control the corona virus keeping in mind the contact rate and vaccination. Keywords:   Covid-19, Double dose Vaccination, Basic Reproduction Number, Global Stability


Modelling And Performance Analysis Of Hydrocyclones: The Case Of Buzwagi Gold Mine, Alphonce Wikedzi, Thomas Mütze Jun 2022

Modelling And Performance Analysis Of Hydrocyclones: The Case Of Buzwagi Gold Mine, Alphonce Wikedzi, Thomas Mütze

Tanzania Journal of Science

The performance of hydrocyclones at Buzwagi Gold Mine (BGM) was investigated in three full scale survey campaigns. Thereafter, several empirical and theoretical hydrocyclone models were used for prediction of hydrocyclone performance. The survey data revealed poor performance of the grinding circuit caused by a circulating load higher than the design. Further, the poor performance of the grinding circuit had consequences on hydrocyclones overflow particle size (i.e. a much coarser product, xP,80 > 200 µm) than target (125 µm). In addition, the operation indicates overloading of the hydrocyclones due to feed rates being 10–18% above the design capacity. Apart from their deficiencies, …


Characterization Of Clay And Granite Dust Blends As Novel Materials For Energy Storage And Diffuser In Constructing Flat-Plate Solar Collector, Tajudeen Kolawole Ajiboye, Mustapha Olawale Fabiyi, Ndagi Mustapha, Sulaiman Abdulkareem Jun 2022

Characterization Of Clay And Granite Dust Blends As Novel Materials For Energy Storage And Diffuser In Constructing Flat-Plate Solar Collector, Tajudeen Kolawole Ajiboye, Mustapha Olawale Fabiyi, Ndagi Mustapha, Sulaiman Abdulkareem

Tanzania Journal of Science

Sun is the main source of solar energy, and the energy it releases to the Earth’s surface in one hour is more than what the whole planet consumes in a year. This present work is about characterizing novel material that can be used as energy storage and diffuser in constructing flat plate solar collector. Materials used are clay and granite dust obtained from Okelele and Kulende Quarry sites, both in Ilorin, Kwara State, Nigeria. The materials were sun-dried; the clay crushed before the two materials were sieved into different particle sizes. They were thereafter blended into different ratios and then …


Potential Economic And Environmental Benefits Of Faecal Sludge Derived Compost And Char Briquettes: The Case Of Dar Es Salaam, Tanzania, Isabela T Mkude, Richard Kimwaga, Sara Gabrielsson Jun 2022

Potential Economic And Environmental Benefits Of Faecal Sludge Derived Compost And Char Briquettes: The Case Of Dar Es Salaam, Tanzania, Isabela T Mkude, Richard Kimwaga, Sara Gabrielsson

Tanzania Journal of Science

The concept of resource recovery, particularly from waste has recently gained much attention and popularity. The aim of this study was to quantify the potential economic and environmental benefits of recovering nutrients and energy from faecal sludge (FS). The empirical data were collected from three unplanned settlements of Dar es Salaam City at Keko, Kipawa and Manzese. Two scenarios were developed to recover nutrients and energy. The estimations of potential amounts of compost and char briquettes were performed by using the resource value mapping (REVAMP) tool. Results from REVAMP indicated daily economic benefits across the study areas ranging between 680 …


Effects Of Temperature And Salinity On Incubation Time, Hatching Success, And Larvae Survival Of The Giant Tiger Prawn Penaeus Monodon Under Experimental Conditions, Sawadi Ndunguru, Marcelian Njau, Blandina Robert Lugendo Jun 2022

Effects Of Temperature And Salinity On Incubation Time, Hatching Success, And Larvae Survival Of The Giant Tiger Prawn Penaeus Monodon Under Experimental Conditions, Sawadi Ndunguru, Marcelian Njau, Blandina Robert Lugendo

Tanzania Journal of Science

Prawns are commercially one of the most important marine resources. However, in their early developmental stages, they face challenges related to physico-chemical and environmental changes. This study aimed at investigating the effects of temperature and salinity on egg incubation time, hatching success, larval and postlarval survival of the giant tiger prawn, Penaeus monodon (Fabricius 1798) obtained from the coastal waters of Tanzania. The adult females P. monodon collected off Rufiji delta were left to acclimatize and spawn at 28.5 ± 0.5 °C and 32 ppt in the hatchery. Spawned eggs were incubated at experimental temperatures of 27 °C, 31 °C …


Carbon Monoxide Oxidation On Model Planar Titania Supported Platinum Nanoparticles Catalyst, Jovine Emmanuel, Brian Hayden Jun 2022

Carbon Monoxide Oxidation On Model Planar Titania Supported Platinum Nanoparticles Catalyst, Jovine Emmanuel, Brian Hayden

Tanzania Journal of Science

A high-throughput (parallel) thermographic screening methodology was developed to enable the measurements of the particle size and support influence on heterogeneous catalysts. A high throughput screening chip has been used to establish the catalytic activity of titania supported platinum nanoparticles catalyst for CO oxidation reaction. The catalytic activity of Pt nanoparticles between 1.3 to 7.8 nm has been investigated for CO conversion at a pressure of 0.11 and 1.1 mbar with O2:CO ratio of 1:1 at 80 °C and 0.6, 1.1 and 2.4 mbar at O2:CO ratio of 1:1 at 240 °C. At these experimental conditions, there was an increase …


Impact Of Radio Operating Environments On Broadband Connectivity, Libe V Massawe, Peter J Chitamu Jun 2022

Impact Of Radio Operating Environments On Broadband Connectivity, Libe V Massawe, Peter J Chitamu

Tanzania Journal of Science

Broadband connectivity and services commonly referred to as the Internet is the key enabling facility for the modern digital economy and the driver for the Fourth Industrial Revolution (4IR or Industry 4.0). In Tanzania, there are over 49% Internet subscriptions for mobile broadband services using 3G UMTS and 4G standards infrastructure, which are predominantly available in urban areas. The non-urban areas remain mostly 2G coverage areas and lack mobile broadband connectivity and services. Transforming existing 2G mobile networks to broadband infrastructure can be achieved by swapping 2G sites with 3G or 4G sites or incrementally replacing 2G sites with 3G …


Weathering The Storm: Community Socio-Economic And Physical Vulnerability Assessment Of Informal Settlements To Disasters In Arusha City, Tanzania, Herbert Hambati Jun 2022

Weathering The Storm: Community Socio-Economic And Physical Vulnerability Assessment Of Informal Settlements To Disasters In Arusha City, Tanzania, Herbert Hambati

Tanzania Journal of Science

Urban population growth has demonstrated a synergetic relationship with the growth of informal settlements and vulnerability to disasters in urban areas. This study employed Community Participatory Vulnerability Assessment (CPVA) to analyse vulnerability in informal settlements in Arusha City, Tanzania. The results show that a plethora of factors, including socio-economic and physical realities interact in complex non-linear ways to shape vulnerability to disasters in informal settlements in the city. The study shows that coping strategies of some individuals in informal settlements reinforce their risks to disasters. This is particularly demonstrated by the stones that are positioned on weak roof structures for …