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Construction Of A High Temperature (~ 200 °C) Oil Pump For Solar Thermal Energy Storage System For Cooking Applications, Jimmy Chaciga, Nyeinga Karidewa, Denis Okello, Benard Tabu

Tanzania Journal of Science

In this study, a positive displacement (PD) oil pump capable of operating at temperatures about 200 °C was constructed using locally available materials. The oil pump was tested to circulate pre-heated refined sunflower oil in Thermal Energy Storage (TES) tank comprising of an oil only and rock pebble-oil system and cooking application. The oil pump was constructed of harden steel and mild steel materials driven by AC/DC electric motor rated 8000 rpm. Standard gear teeth cutting tool was employed to produce the spurs and the pumps’ speed was varied using variable AC transformer connected to 220V AC main source. The …

Electrophoretic Deposition Of Tio2 Thin Films For Photocatalytic Degradation Of Organic Pollutants In Water, Francis W Nyongesa, Bernard O Aduda, Wilson G Nyaga

Tanzania Journal of Science

In this study, electrophoretic deposition (EPD) technique was used to deposit titanium dioxide (TiO2) thin films on conducting glass substrates for application in photocatalytic degradation of organic pollutants in water. Phenol was used as a model pollutant. The EPD suspension related parameters and deposition conditions were first optimized for good quality film deposits. The suspension stability and deposition conditions that result in good adherence of TiO2 particles to the substrate with homogeneous film coatings  are ethanol, a TiO2 solid loading of 4 wt%, a 0.2 wt% iodine concentration in the solvent and a deposition voltage of 20 V in a …

Effects Of Aluminium And Tungsten Co-Doping On The Optical Properties Of Vo2 Based Thin Films, Cephas J Lyobha, Nuru R Mlyuka, Margaret E Samiji

Tanzania Journal of Science

Aluminium and tungsten co-doped vanadium dioxide (VO2:W:Al) thin films were deposited by DC reactive magnetron sputtering technique. In this work we report on the effects of aluminium and tungsten co–doping on the optical properties of vanadium dioxide (VO2) based thin films with a view of combining both increased luminous transmittance (Tlum) and lowered transition temperature (τc). The effect of aluminium and tungsten co-doping on semiconductor-metal transition of vanadium dioxide films was investigated and compared with tungsten doped and undopedVO2films. Spectral transmittances of the films were obtained using Shimadzu SolidSpec-3700 DUV UV-VIS-NIR spectrophotometer. The results revealed that the transmittance of tungsten …

Hall Effect Parameters Of Aluminium And Tungsten Co-Doped Vo2 Thin Films, Mohamed Mussa, Nuru R Mlyuka, Margaret E Samiji

Tanzania Journal of Science

The Hall Effect parameters of Al and W co-doped VO2 thin films were studied in order to explain the effect of co-doping on the electrical properties of thermochromic VO2 films. The carrier concentrations and conductivity of the films were found to increase with increase in temperature while carrier mobility decreased reaching a minimum around the transition temperature then slightly rose and became stable at high temperatures. Tungsten doped films displayed higher carrier concentrations and conductivity on both sides of the metal insulator transition and lower mobility compared to undoped and Al and W co-doped VO2 thin films.

Effects Of Selenized Dc Sputtered Precursor Stacking Orders On The Properties Of Cu2znsnse4 Absorber Layer For Thin Film Solar Cells, Hezekiah B Sawa, Margaret E Samiji, Nuru R Mlyuka

Tanzania Journal of Science

This study investigated the effects of selenized DC sputtered precursor stacking orders on the structural, electrical and optical properties of copper zinc tin selenide (CZTSe) absorber layer for thin film solar cells. The precursors were deposited sequentially on the soda lime glass substrate at room temperature by DC magnetron sputtering. The precursors were selenized by annealing in an atmosphere containing selenium pellets and nitrogen gas. The structural, morphological, optical and electrical properties were respectively characterized using X-Ray Diffractometer (XRD), atomic force microscopy (AFM), UV/VIS/NIR lambda 9/19 spectrophotometer, Hall Effect measurement system (HMS 3000) and a four point probe system. CZTSe …

Optimization Of Zinc To Tin Ratio In A Sol Gel Precursor Solution On The Growth And Properties Of Annealed Czts Thin Films, Justine John Tibaijuka, Margaret E Samiji, Nuru R Mlyuka

Tanzania Journal of Science

CZTS thin films were deposited by sol–gel spin coating method using precursor solutions prepared by dissolving copper acetate dihydrate, zinc acetate dihydrate, tin chloride and thiourea in methanol and monoethylamine then annealed in RTP furnace at 500 °C. Sol–gel precursor solutions were prepared with different Zn/Sn in a precursor solution and were annealed at different time intervals; and their effects on the optical and electrical properties of CZTS (Cu2ZnSnS4) films were investigated. The optical band-gap values were estimated to be between 1.30 and 1.88 eV while the absorption coefficients were in the range of 104 cm–1 in the visible region. …

Compositional And Thickness Effects On The Optical Properties Of Zinc–Doped Selenium–Antimony Thin Films, Austine A Mulama, Julius M Mwabora, Andrew O Oduor, Cosmas M Muiva

Tanzania Journal of Science

Chalcogenide system of antimony (Sb)-selenium (Se)-zinc (Zn) system is a promising semiconductor for phase change memory devices due to its thermal stability and low power consumption. The study investigated the effect of film thickness and zinc content on the optical properties of thermally evaporated Sb10Se90-xZnx (x = 0, 5, 10 & 15 at. %) thin films. It was found that transmittance (T~ 85-40%) and optical band gap energy (Eopt ~ 1.60 eV – 1.22 eV) decreased but absorption coefficient (α~0.840–2.031 104 cm–1) increased with increase in zinc content. Furthermore, as the film thickness increased from 53 ± 5 nm to …

Effects Of Thickness Variation In The Multilayer Thin Film On The Performance Of Eta Solar Cell, Robinson J Musembi

Tanzania Journal of Science

A highly structured eta solar cell of the type TiO2/In(OH)xSy/Pb(OH)xSy/PEDOT:PSS/Au with different layer thickness has been fabricated using various deposition techniques for each layer in the stack. The solar cell parameters, Uoc, FF and  have been extracted from current- voltage characteristics measurements. The buffer layer and the hole collector layer have been kept constant while the window and the absorber layer have been varied. The thickness of either of the two layers being varied has been observed to affect the performance of the solar cells. The difference in thickness has been attributed to affect the charge lifetime in the space …

Thermal Performance Of Selected Oils In Uganda For Indirect Solar Domestic Cooking Applications, Benard Tabu, Karidewa Nyeinga, Jimmy Chaciga, Denis Okello

Tanzania Journal of Science

This study experimentally evaluated the thermal performance of selected oils in Uganda for indirect solar domestic cooking applications. The oil samples used were refined sunflower oil, refined palm oil and thermia B. These oils are locally available in Uganda. Thermal stratification, energy and exergy analysis were performed for each oil to determine their suitability for Thermal Energy Storage (TES) using a thermosiphon principle. The results showed that thermal stratification of refined sunflower oil was higher as compared to refined palm oil and thermia B during the first one hour. The stored energy and exergy for refined sunflower oil was generally …

Effects Of Substrate Radial-Position Relative To The Sputter-Gun Axis On The Electrical, Optical And Structural Properties Of Zno Thin Films Deposited By Reactive Direct Current Magnetron Sputtering, John Paul Eneku, Tom Otiti, Julius Mwakondo Mwabora, David Horwat

Tanzania Journal of Science

ZnO thin films were deposited using reactive direct current (dc) magnetron sputtering on glass substrates placed at seven variable radial positions (-1, 0, 1, 2, 3, 4 and 5 cm)  relative to the sputter-gun (target) axis. A pure zinc target was used and sputtering carried out in argon and oxygen atmosphere with flow rates of 50 sccm and 6 sccm, respectively. XRD characterization showed that, all films crystallized homogeneously in the wurtzite phase with a strong (002) and a weak (004) orientations. Film crystallinity was very low at substrate positions located less than or equal to 1 cm from the …

Tense Sensitivity Of Shambala Relative Markers, Salehe Kaoneka

Journal of Humanities and Social Sciences

This article goes a step ahead from the focus of relative clause formation strategies in Shambala provided in previous Shambala studies (c.f. Besha, 200; and Riedel, 2009). It describes relative formation strategies in the Shambala Bantu language (G.23) by focusing on the analysis of the constraints posed by relative markers on tense systems of the language. The study reveals three important issues: first, the positioning of the Shambala relative markers is highly constrained by tense; second, in unmarked situations, every relative marker is restricted to a particular tense; and third, when marked, some relative markers may refer to other tenses …

Profit Efficiency And Smallholder Sugarcane Out-Growers Under Contract Farming In Tanzania: Does Location Matter?, Thobias Nsindagi, Jennifer K. Sesabo

Journal of Humanities and Social Sciences

Tanzania is among countries that value the sugarcane sector as one of the potential crops for poverty alleviation. The sector provides direct employment to about 14,000 people, and it is an outlet for the produce of over 30,000 farming households (Nkonya & Barreiro Hurle, 2012). Likewise, it provides direct earnings and savings amounting to about US$28m annually (Sugar Board of Tanzania (SBT), 2007). However, sugarcane out-growers in Tanzania have been getting low prices relative to unit costs (Matango, 2006). This has generated substantial debate about the need and level of government support. Like other developing countries, contract farming (CF) has …

Motivation For Learning Chinese As A Foreign Language: Experiences From Duce, Emmanuel Ilonga Dr

Journal of Humanities and Social Sciences

This study explores the motivation for learning Chinese language at the Dar es Salaam University College of Education (DUCE). The major objective is to find out the reasons that motivated learners to enrol into the optional Chinese language course. The data used in the study was gathered through questionnaires and structured interviews. The presentation of findings reflected four types of motivation: intrinsic, extrinsic, integrative, and lastly, instrumental motivation. The results revealed that learners’ motivation for learning Chinese as a foreign language at the DUCE includes personal contentedness, developing base for further education abroad, integrating with the Chinese community and learning …

Literary Cartography: The Mapping Of Colonial And Post-Colonial Races In Vassanji’S The Gunny Sack, Edith Bwana

Journal of Humanities and Social Sciences

Colonialism was institutionalised by the demarcation of borders and spaces. Society was divided along racial and economic lines, separating the ruling class of Europeans and Asian middlemen from the majority Africans who were ruled. In the struggle to establish a national identity in the post-colonial era, similar demarcations were created with the purpose of establishing a unified and consolidated nation state, again dividing society along similar racial categories. In this process, minority social groupings were ignored and written out of history in favour of a homogenous national narrative. The novel The Gunny Sack, by M.G Vassanji, attempts to remap the …

Historiography Of Industrialization In Nigeria: 1914–1960, Chris. B.N Ogbogbo, Ayodele Samuel Aborisade

Journal of Humanities and Social Sciences

The historiography of industrialization in Nigeria has a rich but confused literature. Scholars from various disciplinary orientations have engaged this subject matter from perspectives that have complexified the idea and concept of industrialization in a colonial state. This study interrogates the various perspectives of intellectual inquiry on industrialization of colonial Nigeria, and argues that although industries and industrial activities existed in pre-colonial and colonial Nigeria, industrialization between 1914 and 1960, as portrayed by a number of scholars, was a farce. Thus, the interrogation of theoretical and historical explanation of industrialization by scholars as one of the important components of colonial …

A Syntactic Analysis Of Relative Clauses In The Southern Cushitic Language, Iraqw, Chrispina Alphonce

Journal of Humanities and Social Sciences

The article offers an account of the syntax of relative clauses in Iraqw, a Southern Cushitic language of the Afroasiatic Micropylum spoken in northern Tanzania. It examines the structure of relative clauses, relativization strategies, relative markers and noun phrase accessibility hierarchy (AB). Using the descriptive research design, coupled with the qualitative approach, data were generated through elicitation. 8 informants were sampled through snowball technique to inform the study. Text collection was also done to identify relative clauses. The analysis of the data obtained revealed the following: (i) Iraqw displays postnominal relative clause, the feature that is common in most of …

Acquiring Knowledge About The Use Of A Newly Developed Electronic Fetal Heart Rate Monitor: A Qualitative Study Among Birth Attendants In Tanzania, Sara Rivenes Lafontan, Johanne Sundby, Hussein Kidanto, Columba Mbekenga, Hege L. Ersdal

School of Nursing & Midwifery, East Africa

In an effort to reduce newborn mortality, a newly developed strap-on electronic fetal heart rate monitor was introduced at several health facilities in Tanzania in 2015. Training sessions were organized to teach staff how to use the device in clinical settings. This study explores skilled birth attendants’ perceptions and experiences acquiring and transferring knowledge about the use of the monitor, also called Moyo. Knowledge about this learning process is crucial to further improve training programs and ensure correct, long-term use. Five Focus group discussions (FGDs) were carried out with doctors and nurse-midwives, who were using the monitor in the labor …

Identity, Values And Norms Of East Africa’S Youth, Alex Awiti, Caleb Orwa

East Africa Institute

With a median age estimated at 18 years, East Africa is one of the youngest regions in the world. However, relatively little research has been conducted to understand how they identify themselves and what values and norms shape or influence them. About 7,000 individuals between the age of 18 and 35 were interviewed in Kenya, Tanzania, Rwanda and Uganda. Youth constructed their identity along four dimensions; youth (age-associated); nationality; faith; family. However, country, religion, gender and age influenced the ordering of identity. With the exception of Rwanda, East African a tolerance for rule violation and corruption was prevalent among East …

Discovery From Failure: Understanding Developing Countries' Battles With Poverty And Culturally Appropriate Answers To Them, Daniel Tennant

Honors Theses

This paper is an examination of a failed research attempt, followed by examination of successful research literature on the subject of the informal economy and poverty. The research is centered on peripheral regions of the world, namely in Sub-Saharan countries such as Senegal. The informal economy continues to grow without thorough understanding or measurement of it creating greater problems in the future. The examination highlights the need for culturally appropriate questions, methodologies, and answers to issues of poverty in developing countries. Western World bias needs to be considered when creating and executing research in developing countries if the results are …

Establishing Trust In Hiv/Hcv Research Among People Who Inject Drugs (Pwid): Insights From Empirical Research, Roberto Abadie, Shira Goldenberg, Melissa Welch-Lazoritz, Celia B. Fisher

Department of Sociology: Faculty Publications

Background — The establishment of trust between researchers and participants is critical to advance HIV and HCV prevention particularly among people who inject drugs (PWID) and other marginalized populations, yet empirical research on how to establish and maintain trust in the course of community health research is lacking. This paper documents ideas about trust between research participants and researchers amongst a sub-sample of PWID who were enrolled in a large, multi-year community health study of social networks and HIV/HCV risk that was recently conducted in rural Puerto Rico.

Methods — Qualitative research was nested within a multi-year Social Network and …

Exploring The Use Of Multiliteracies Pedagogy In The Teaching Of English Language In A Secondary School In Koboko District, Uganda: Action Research, Lilian Amaniyo

Master of Education

Pedagogical approaches in educational contexts continue to evolve with emerging global trends in work, social and cultural settings, putting educators to task to choose best practices that are relevant to their learning contexts. The Multiliteracies pedagogy provides a flexible approach that is capable of negotiating the multiple cultural diversities and modes of communication and meaning making in current times. This study explored the use of Multiliteracies pedagogy in the teaching of English language in one secondary school in Koboko District in Uganda. Multiliteracies pedagogy is an approach that seeks to develop broader generic and literacy skills other than linguistic skills …

Use Of Rubric In Assessment To Support Learning, Dennis Odhiambo Ogollah

Master of Education

The study involved an intervention on use of rubrics in assessment with an aim of empowering teachers and students with skills and knowledge that would facilitate implementation of assessment for learning strategies to promote student engagement in learning. This was conducted by adopting quasi experimental design and quantitative approach that involved administering of pretest and posttest to the treatment and control group and the results analyzed using t-test analysis to establish the effect of intervention. A total of 40 students from two form three classes that formed treatment and control group by random selection, participated in the research, with control …

Exploring Effects Of Teachers‟ Perception Towards Standardized Tests: A Case Study Of Primary Schools In Soroti Municipal Council, Uganda, Agera Thomas

Master of Education

The purpose of the study was to explore the effects of teachers‟ perception towards standardized tests within government aided primary schools of Soroti Municipal Council in Eastern region, Uganda. A researcher used qualitative approach and case study design was adopted whereby data collected revealed what people thought, experienced and believed rather than prior prejudice, assumptions that bias data collection, analysis to research conclusion. Data was collected using qualitative methods and tools of survey, interview, document analysis and questionnaires, interview guide, document analysis protocol respectively. A total number of 18 respondents that comprised 02 head teachers, 08 primary seven teachers and …

Exploring Public Primary School Teachers’ Use Of Learners’ Funds Of Knowledge To Teach Literacy, Francis B. Shayo

Master of Education

This study aimed to explore public primary school teachers’ use of learners’ FoK to teach literacy in five public primary schools in Korogwe Town council. The purpose of the study was to explore the extent to which learners’ FoK is used to teach literacy. The study used mixed approach in which both qualitative and quantitative methods were applied whereby 70 participants were sampled through purposive and random sampling procedures. The participants included 50 standards III and IV teachers and 20 pupils from the same classes. Data were collected using questionnaires, focus group discussion, class observations, and interviews. The qualitative data …

Addressing Cultural Diversity In Early Childhood Classes: What Are Teachers Competencies?, Prezy Emanuel Ramadhani

Master of Education

Addressing cultural diversity (CD) has become an issue of discussion worldwide particularly in early childhood care and education institutions, on how practitioners address the learning needs of children from a diverse cultural background (DCB) in their classrooms. In Tanzania particularly in Korogwe town, like another different part of the world, early childhood classes are populated with children from the DCB. Yet, little is on documents on how practitioners address the LNC from the DCB. The purpose of this study was to investigate the competences of early childhood practitioners (ECPs) in addressing the LNC from the DCB. The study adopted a …

Exploring Teachers’ Interventions In Enhancing Grade One School Readiness, Rawa Ghaleb Afara

Master of Education

This study investigates first-grade teacher’s intervention to support learners in grade one who are not yet ready for school. It was undertaken to give a clear insight into the intervention that grade-one teachers do to assist learners for a smooth transition in grade one. In addition it looked at the challenges that affect teacher education practices. Most research studies examined readiness by focusing on the skills which children should have before going to school. Limited studies investigated ‘readiness’ by examining the role of teachers in handling children in grade one especially those who were not ready emotionally, cognitively and behaviorally. …

Investigating The Influence Of Non-Technical Words To The Teaching And Learning Of Science: A Case Study Of A Primary School In Taveta Sub-County, Buya Yorrum Komora

Master of Education

Teaching of science has been found to be most challenging. These challenges are believed to be due to lack of apparatus used for teaching, class size, and inadequate curriculum materials but also the language used to teach science. During the process of teaching, learners face the problem of not understanding the meaning of non-technical words and how they create regular explanation of the knowledge itself. Non-technical words refer to words that have one or multiple meanings in our daily language but carry exact and specific meaning, and different when used in scientific context. Studies have shown that learners only experience …

The Roles Of Internal Instructional Supervision In Enhancing Teachers Effectiveness: A Case Study Of Two Primary Schools In Awere Sub-County Pader District, Uganda, Otto George

Master of Education

Internal instructional supervision in school is considered a vital practice in improving teacher’s instructional practice and greater academic achievement of learners. This study provides an exploration of the significant roles internal instructional supervision plays towards enhancement of teacher effectiveness. The study further seeks to establish the relationship between internal instructional activities and effective teaching at school level. The study adopted a qualitative case study design in which two schools were investigated. The respondents in this study include headteacher, deputy headteacher, head of departments, and teachers. In an attempt to gather the data required in this study, one on one semi …

An Investigation Of Primary Children’S Misconceptions On Floating And Sinking Concepts: A Survey In One Government Primary School In Soroti Municipality, Eastern Uganda, Cathy Martha Akello

Master of Education

Floating and sinking concepts are part of the science curriculum in Uganda, an important topic applicable in everyday life. Globally teaching and learning of floating and sinking concepts pose a challenge to both teachers and learners in the primary schools. This has led to a number of common misconceptions resulting to persistent errors in learners’ performance. These misconceptions tend to be difficult to remediate if not handled in children’s early years of education. A sample of one hundred learners of grade 5 aged 10-15 years participated in the study. Questionnaires were used to elicit learner’s misconceptions about the floating and …

An Examination Of The Role That Integration Plays In Promoting Teaching And Learning For Refugee Learners In Secondary Schools: Case Study Of Public Secondary Schools In Moyo District Uganda, Tiondi Patrick

Master of Education

In attempt to provide free education for all refugee children in the country, the Government of Uganda introduced Refugees Act 2006 and Refugees Regulations Act 2010 which empowered refugee children to access and enjoy basic education like any other nationals. The purpose of this study was to examine the role that integration plays in promoting teaching and learning for refugee learners in secondary schools in Uganda particularly Moyo District. The study adopted qualitative approach with case study design in one of the purposively selected public secondary school in Moyo district. Data was collected from fifteen participants namely head teacher, teachers, …