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Articles 57511 - 57540 of 294391

Full-Text Articles in Physical Sciences and Mathematics

The Telsam Protein Polymer Significantly Improves The Speed And Propensity Of Crystallization Of Target Proteins, Seyedeh Sara Soleimani Jun 2022

The Telsam Protein Polymer Significantly Improves The Speed And Propensity Of Crystallization Of Target Proteins, Seyedeh Sara Soleimani

Theses and Dissertations

While conducting pilot studies into the usefulness of fusion to TELSAM polymers as a potential protein crystallization strategy, we observed novel properties in crystals of two TELSAM–target protein fusions, as follows. (i) A TELSAM–target protein fusion can crystallize more rapidly and with greater propensity than the same target protein alone. (ii) TELSAM–target protein fusions can be crystallized at low protein concentrations. This unprecedented observation suggests a route to crystallize proteins that can only be produced in microgram amounts. (iii) The TELSAM polymers themselves need not directly contact one another in the crystal lattice in order to form well-diffracting crystals. This …

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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 …

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Empirical Assessment Of Big Data Technology Adoption Factors For Organizations With Data Storage Systems, Ahmad B. Alnafoosi Jun 2022

Empirical Assessment Of Big Data Technology Adoption Factors For Organizations With Data Storage Systems, Ahmad B. Alnafoosi

College of Computing and Digital Media Dissertations

Many organizations have on-premises data storage systems. Data storage systems are evolving in multiple ways. One way is the adoption of Big Data. Big Data is a data storage system with the ability to analyze large volumes, velocity, and a variety of data. Per the Economist, data is now the most valuable resource (Parkins, 2017). Big Data holds the promise of unlocking a substantial value of data stored. Yet many organizations are not implementing Big Data. There is a need to identify key factors affecting adoption for such organizations. The literature review revealed multiple gaps in studied adoption factors (un-studied …

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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 …

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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 …

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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 …

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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 …

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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 …

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Nuclear Fuel Cycle: Safe Management Of Spent Nuclear Fuel, Robert L. Sindelar Jun 2022

Nuclear Fuel Cycle: Safe Management Of Spent Nuclear Fuel, Robert L. Sindelar

Journal of the South Carolina Academy of Science

The aim for storage of spent nuclear fuel (SNF) either in wet or in dry storage systems is to ensure general safety objectives are met throughout a desired storage period. Staff at the Savannah River National Laboratory (SRNL), in collaborations with partners at other national laboratories, industry research organizations, and the University of South Carolina (UofSC), have performed materials aging testing and analyses, and have established nuclear materials aging management programs to support extended periods of safe storage of research reactor (RR) SNF and of commercial power reactor (PR) SNF pending ultimate disposal. Several example challenges include susceptibility of aluminum …

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Co-Microencapsulation Of Ruellia Tuberosa L. And Cosmos Caudatus K. Extracts For Pharmaceutical Applications, Choirin Annisa, Sasangka Prasetyawan, Anna Safitri Jun 2022

Co-Microencapsulation Of Ruellia Tuberosa L. And Cosmos Caudatus K. Extracts For Pharmaceutical Applications, Choirin Annisa, Sasangka Prasetyawan, Anna Safitri

Makara Journal of Science

This study aims to co-microencapsulate the Ruellia tuberosa L. and Cosmos caudatus K. extracts, with chitosan–sodium tripolyphosphate (Na-TPP) as coating material. α-Amylase inhibition and antioxidant assays were conducted to determine the potential of microcapsules used as antidiabetic agents. The microcapsules were manufactured under the influences of pH, Na-TPP concentration, and stirring time. The optimum microencapsulation conditions were selected based on the highest encapsulation efficiency. The optimum microencapsulation conditions were a pH of 4, Na-TPP concentration of 0.15% (w/v), and stirring time of 60 min. The microcapsules exhibited an IC50 (inhibitory concentration) value of 223.64 ± 0.81 µg/mL and an …

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Phytochemical, Antibacterial, Antifungal, And Hemagglutination Screening Of Quercus Agrifolia Nee Root Extracts, Abdul Wahab, Arshad Farid, Muhammad Muzammal Jun 2022

Phytochemical, Antibacterial, Antifungal, And Hemagglutination Screening Of Quercus Agrifolia Nee Root Extracts, Abdul Wahab, Arshad Farid, Muhammad Muzammal

Makara Journal of Science

In the current study, the roots of Quercus agrifolia Nee were subjected to phytochemical analysis to determine the presence of various compound groups. To explore the effect of Quercus agrifolia Nee roots, we evaluated four solvent extracts, namely, crude ethanolic extract (CEE), n-hexane, chloroform (CHCl3), and ethyl acetate (EtOAc), for their antibacterial, antifungal, and hemagglutination activities. Agar well diffusion and agar tube dilution methods were used to determine the antibacterial and antifungal effects, respectively, and hemagglutination activity was measured against human erythrocyte blood groups. The qualitative phytochemical analysis of the solvent extracts of Quercus agrifolia Nee roots …

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Preparation Of Zn/Al-Chitosan Composite For The Selective Adsorption Of Methylene Blue Dye In Water, Risfidian Mohadi, Patimah Mega Syah Bahar Nur Siregar, Neza Rahayu Palapa, Aldes Lesbani Jun 2022

Preparation Of Zn/Al-Chitosan Composite For The Selective Adsorption Of Methylene Blue Dye In Water, Risfidian Mohadi, Patimah Mega Syah Bahar Nur Siregar, Neza Rahayu Palapa, Aldes Lesbani

Makara Journal of Science

Layered double hydroxide (LDHs) are widely used adsorbents for methylene blue removal. However, LDHs have a perishable structure that cannot be used repeatedly. Modifying LDHs with chitosan produces a strong material with a large surface area for methylene blue adsorption. Adsorption conditions were optimized by determining the adsorption isotherms and the adsorbent regeneration process. Results showed that the adsorption process was balanced in 90 min with maximum adsorption capacities of 86.207 mg/g, 35.336 mg/g, and 98.039 mg/g for Zn/Al, chitosan, and Zn/Al-chitosan, respectively. The adsorption in this study followed the Freundlich isotherm model. Regeneration analysis of the adsorbent showed that …

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Silver Nanoparticles’ Biosynthesis And Characterization With The Extract Of Jatropha Curcas Leaf: Analysis Of Corrosion Inhibition Activity, Talabi Henry Kayode, Talabi Justina Yetunde, Adewuyi Benjamin Omotayo Jun 2022

Silver Nanoparticles’ Biosynthesis And Characterization With The Extract Of Jatropha Curcas Leaf: Analysis Of Corrosion Inhibition Activity, Talabi Henry Kayode, Talabi Justina Yetunde, Adewuyi Benjamin Omotayo

Makara Journal of Science

The plant-mediated nanoparticles synthesis process is gaining popularity because of its effective cost, eco-friendliness, and nontoxic nature. The current study presents the silver nanoparticles (AgNPs) which synthesized with AgNO3 as precursor salt and Jatropha curcas leaf extract. J. curcas leaf extract has phytochemicals that could reduce the precursor metal salt to nanoparticles and act as a capping agent surround the nanoparticles to enhance its stability. Phytochemical screening on J. curcas leaf extract showed that alkaloids, saponins, tannins, flavanoids, steroids, philobatannins, phenols, and cardiac glycosides are contained in the sample. The biosynthesized nanoparticles were investigated by UV-visible (UV-vis) spectroscopy, X-ray …

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Jatropha Tanjorensis A Flora Of Southeast Nigeria: Isolation And Characterization Of Naringenin And Validation Of Bio-Enhanced Synergistical Activity Of Α- Tocopherol Toward Clinical Isolates Of Resistant Bacterial, Ikechukwu Kingsley Ijoma, Vincent Ishmael Egbulefu Ajiwe Jun 2022

Jatropha Tanjorensis A Flora Of Southeast Nigeria: Isolation And Characterization Of Naringenin And Validation Of Bio-Enhanced Synergistical Activity Of Α- Tocopherol Toward Clinical Isolates Of Resistant Bacterial, Ikechukwu Kingsley Ijoma, Vincent Ishmael Egbulefu Ajiwe

Makara Journal of Science

Jatropha tanjorensis is among the rich floras of Southeast Nigeria and used by ethnic people to treat infections and manage health conditions. Ethnomedicine has long been employed in the treatment of ailments caused by bacterial pathogens. Studies showed that the incorporation of synthetic α-tocopherol to an antibacterial agent improves its activity. However, knowledge about the antibacterial-enhanced activity of plant-based α-tocopherols, especially those isolated from Jatropha tanjorensis, is limited because of the different bioactivities of synthetic and natural α-tocopherols. To determine the phytochemicals in J. tanjorensis, we carried out the structural elucidation of its leaf extracts. Naringenin and α-tocopherol …

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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 …

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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 …

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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 …

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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 …

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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

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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

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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, …

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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 …

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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 …

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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 …

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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 …

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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 …

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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 …

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Charcoal Whirlwinds And Post-Fire Observations In Serengeti National Park Savannahs, Colin J. Courtney Mustaphi, Heleen C. Vos, Rob Marchant, Colin Beale Jun 2022

Charcoal Whirlwinds And Post-Fire Observations In Serengeti National Park Savannahs, Colin J. Courtney Mustaphi, Heleen C. Vos, Rob Marchant, Colin Beale

Tanzania Journal of Science

Whirlwinds and visible dust devils occur over semi-arid ecosystems and entrain particles from the ground surface. Fires produce abundant charcoal across savannahs and the resulting blackened surfaces create a large albedo contrast. Whirlwinds have been observed associated with active fires; yet, there are few published observations on post-fire landscapes. Spatiotemporal patterns of whirlwinds have been documented for a limited number of regions and have not been made for the ecosystems of eastern Africa. From field-based sightings in the Serengeti National Park, Tanzania, we report on whirlwinds over burned savannah patches that entrained large quantities of charcoal to produce black coloured …

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Ultrafast Electron Diffraction: Visualizing Dynamic States Of Matter, D. Filipetto, P. Musumed, R. K. Li, B. J. Siwick, M. R. Otto, Martin Centurion, J. P.F. Nunes Jun 2022

Ultrafast Electron Diffraction: Visualizing Dynamic States Of Matter, D. Filipetto, P. Musumed, R. K. Li, B. J. Siwick, M. R. Otto, Martin Centurion, J. P.F. Nunes

Martin Centurion Publications

Since the discovery of electron-wave duality, electron scattering instrumentation has developed into a powerful array of techniques for revealing the atomic structure of matter. Beyond detecting local lattice variations in equilibrium structures with the highest possible spatial resolution, recent research efforts have been directed towards the long sought-after dream of visualizing the dynamic evolution of matter in real-time. The atomic behavior at ultrafast timescales carries critical information on phase transition and chemical reaction dynamics, the coupling of electronic and nuclear degrees of freedom in materials and molecules, the correlation between structure, function and previously hidden metastable or nonequilibrium states of …

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The Average Number Of Divisors In Certain Arithmetic Sequences, Liubomir Chiriac Jun 2022

The Average Number Of Divisors In Certain Arithmetic Sequences, Liubomir Chiriac

Mathematics and Statistics Faculty Publications and Presentations

In this paper we study the sum p≤xτ(np), where τ(n) denotes the number of divisors of n, and {np} is a sequence of integers indexed by primes. Under certain assumptions we show that the aforementioned sum is x as x → ∞. As an application, we consider the case where the sequence is given by the Fourier coefficients of a modular form.

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