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Heavy Metal Contamination And Potential Ecological Risks In Surface Sediments Along Dar Es Salaam Harbour Channel, Benard Mwakisunga, Harishchandra B. Pratap, John F. Machiwa, Flora Stephano
Heavy Metal Contamination And Potential Ecological Risks In Surface Sediments Along Dar Es Salaam Harbour Channel, Benard Mwakisunga, Harishchandra B. Pratap, John F. Machiwa, Flora Stephano
Tanzania Journal of Science
Investigation of heavy metal contamination along Dar es Salaam harbour channel was carried out in order to determine their current concentrations, sources and potential ecological risks to benthic biota. Sampling was carried out from January to May 2019 and samples analysed using ICP-OES and C-H-N-S analyser. Analysis of heavy metal relationships showed that, Cu, Zn, Cr, As, Ni, Co, Fe, Cd had strong relationships with each other, while Pb only related to Zn. Principal component analysis partitioned metals into two groups; PC1: Ni, Cr, Fe, Co, As, Cu, Cd, and Zn explaining 73.6% variance and PC2: Pb, Zn, and Cd …
Effects Of Ripeness And Blending Speed On The Extraction Yield And Physical Chemical Properties Of Low Viscosity Banana Juice, Oscar Kibazohi, Victor V Matabura
Effects Of Ripeness And Blending Speed On The Extraction Yield And Physical Chemical Properties Of Low Viscosity Banana Juice, Oscar Kibazohi, Victor V Matabura
Tanzania Journal of Science
Low viscosity banana juice can be extracted from banana by blending and pressing the resulted semi-solid pulp to separate the juice. This juice extraction technology is relatively new and further studies to understand key parameters for juice release is vital for scaling up production and commercialisation. This study, investigated the influence of blending speed and ripeness stage on banana juice yield using two banana cultivars; the East African highland banana (Mbile) and the exotic banana (Pisang awak). Types of sugars and organic acids in the juice were analysed using an HPLC. Changes with ripening of fruit firmness, juice pH and …
Analogue Sandbox Scaled Modelling Of Oblique And Orthogonal Extension Rifting In Rukwa Rift Basin, Tanzania, Tonny Ojok, John Bk Duot, Majorine Namaganda, Nasra Sadiki, Michael Msabi
Analogue Sandbox Scaled Modelling Of Oblique And Orthogonal Extension Rifting In Rukwa Rift Basin, Tanzania, Tonny Ojok, John Bk Duot, Majorine Namaganda, Nasra Sadiki, Michael Msabi
Tanzania Journal of Science
Fault evolution in oblique and orthogonal rift systems in the brittle upper crust of the Rukwa rift basin was simulated using scaled sandbox modelling by varying the angle between the rift axis and the extension direction, α, through 45° and 90°, over a 10 cm displacement. The 45° oblique model exhibits a half-graben architecture bounded by a planar fault, intra-rift faults and a conjugate fault in some vertical sections. The map view of the model’s basin trends in the NW-SE direction, and is comparable with the Rukwa rift basin orientation. The 90° oblique model forms a basin structure which is …
Critical Analysis Of Material Consumption And Cost Reduction Techniques For The Apparel Cutting Processes, Ismael Taifa, Ibrahim Twaha, Mboka A Mwakibambo
Critical Analysis Of Material Consumption And Cost Reduction Techniques For The Apparel Cutting Processes, Ismael Taifa, Ibrahim Twaha, Mboka A Mwakibambo
Tanzania Journal of Science
Revenues generation in the garment industry is synonymous with material consumption. This study thus analysed material consumption and cost reduction techniques in the Tanzanian garment industry. The research employed quantitative (experimentation) and qualitative approaches (document review and observation technique) in the apparel cutting processes. Experimental results of material consumption from ten tests averaged efficiency of 78.67%, the wasted pieces (19.2%), and unnoticed waste (2.03%). Essential considerations to reduce material waste include: digitalising the fabric cutting processes; providing workers training; deploying appropriate practices in the cutting room (e.g. pattern engineering and pattern accuracy); considering the quality of the procured fabric and …
Adaptive Sliding Mode Contouring Control Design Based On Reference Adjustment And Uncertainty Compensation For Feed Drive Systems, Mathew Renny Msukwa, Santos Kihwele
Adaptive Sliding Mode Contouring Control Design Based On Reference Adjustment And Uncertainty Compensation For Feed Drive Systems, Mathew Renny Msukwa, Santos Kihwele
Tanzania Journal of Science
Industrial feed drive systems, particularly, ball-screw and lead-screw feed drives are among the dominating motion components in production and manufacturing industries. They operate around the clock at high speeds for coping with the rising production demands. Adversely, high-speed motions cause mechanical vibrations, high-energy consumption, and insufficient accuracy. Although there are many control strategies in the literature, such as sliding mode and model predictive controls, further research is necessary for precision enhancement and energy saving. This study focused on design of an adaptive sliding mode contouring control based on reference adjustment and uncertainty compensation for feed drive systems. A combined reference …
Pair Distribution Function Analysis And Electrochemical Performance Of Mesoporous Carbon Nanomaterials Synthesized Through Koh And Zncl2 Activation, Talam E. Kibona, Sarah Frisco, Maxwell W. Terban
Pair Distribution Function Analysis And Electrochemical Performance Of Mesoporous Carbon Nanomaterials Synthesized Through Koh And Zncl2 Activation, Talam E. Kibona, Sarah Frisco, Maxwell W. Terban
Tanzania Journal of Science
Mesoporous carbon has been synthesized by activating carbonized biogas slurry residues with ZnCl2 and KOH simultaneously. The carbon to activating agent mass ratios were kept at 1:4, while the ZnCl2 to KOH mass ratio varied from 4:0, 3:1, 2:2, 1:3, to 0:4. The highest BET specific surface area of 361 m2 g-1, micropore surface area of 231 m2 g‒1, mesopore surface area of 125 m2 g‒1, and total pore volume of 0.23 cm3 g‒1 which amounted to 78% mesopore content, were obtained for the sample with 3:1 ZnCl2 to KOH mass ratio. Scanning electron microscope (SEM) images were acquired to …
Analysing Climate Change Mitigation Policy Options In The Renewable Energy Sub-Sector In Tanzania, Ladislaus Kyaruzi, Patrick M Ndaki, Richard Ym Kangalawe
Analysing Climate Change Mitigation Policy Options In The Renewable Energy Sub-Sector In Tanzania, Ladislaus Kyaruzi, Patrick M Ndaki, Richard Ym Kangalawe
Tanzania Journal of Science
Public policies influence reduction of greenhouse gas emissions. Also the extent to which policies are developed and implemented can influence the achievement of the national, regional and international climate change mitigation policy framework in the renewable energy sub-sector. This paper provides a critical overview of key policy options influencing the development of renewable energy sub-sector through climate change mitigation policy options in Tanzania. Questionnaire surveys were used to collect primary data from 100 relevant experts who represented 64 organizations in Tanzania. Secondary data were collected by literature review. The state of climate change mitigation policy options in the renewable energy …
Advances In Nanomaterials Sciences And Nanotechnology For Sustainable Development: A Review, Gervas E. Assey, Wilhelm S. Malasi
Advances In Nanomaterials Sciences And Nanotechnology For Sustainable Development: A Review, Gervas E. Assey, Wilhelm S. Malasi
Tanzania Journal of Science
The fields of materials sciences have great opportunities to address the challenges of sustainable development of modern societies. The sub-disciplines of materials sciences of interest in this review are nanomaterials sciences and nanotechnology. Nanomaterials possess one external dimension measuring 1-100 nm. They have larger surface area for the same mass than their bulk materials. They are more reactive with effects on their electrical, optical and magnetic properties. Thus, nanomaterials are promising for sustainable development in the areas of energy, water, chemicals, electronics, medical and pharmaceutical industries, CO2 mitigation and agriculture. To this end, this review explores the advances in nanomaterials …
Impacts Of Wood Fuel Uses On Forest Cover: The Case Of Semiarid Areas In Northern Tanzania, Debora J Mahushi, Revocatus L Machunda, Talam E Kibona
Impacts Of Wood Fuel Uses On Forest Cover: The Case Of Semiarid Areas In Northern Tanzania, Debora J Mahushi, Revocatus L Machunda, Talam E Kibona
Tanzania Journal of Science
Satellite images for the years 1987, 1997, 2002 and 2017, and questionnaire surveys were used to assess energy sources and demands as well as the impacts of wood fuel use to forest cover changes in Meru and Mwanga Districts. The major energy sources identified include cow dung cake, firewood, charcoal, liquefied petroleum gas and biogas. The total energy demands from these sources were 1400 (in Meru), 6289, 724 and 21 kg per day, respectively. The amount of biogas was not quantified since the reactors were constructed locally with no reading meter. Analysis from Landsat images showed variations in forest cover. …
Inversion–Free Iterative Method For Finding Symmetric Solution Of The Nonlinear Matrix Equation X-A^* X^Q A=I (Q≥2), Chacha Stephen Chacha
Inversion–Free Iterative Method For Finding Symmetric Solution Of The Nonlinear Matrix Equation X-A^* X^Q A=I (Q≥2), Chacha Stephen Chacha
Tanzania Journal of Science
In this paper, we propose the inversion free iterative method to find symmetric solution of the nonlinear matrix equation where is an unknown symmetric solution, is a given Hermitian matrix and is a positive integer. The convergence of the proposed method is derived. Numerical examples demonstrate that the proposed iterative method is quite efficient and converges well when the initial guess is sufficiently close to the approximate solution. Keywords: Symmetric solution, nonlinear matrix equation, inversion free, iterative method.
Vulnerability And Responses Of Smallholder Farmers To Climate Change Effects In Semiarid Areas Of Bahi And Kongwa Districts, Tanzania, Helena Elias Myeya
Vulnerability And Responses Of Smallholder Farmers To Climate Change Effects In Semiarid Areas Of Bahi And Kongwa Districts, Tanzania, Helena Elias Myeya
Tanzania Journal of Science
This study examined the vulnerability and responses of smallholder farmers to climate change effects in Semiarid Areas of Bahi and Kongwa Districts. A total of 366 household heads were involved in this study. The study employed questionnaire, interviews and documentary review as data collection techniques. Archival data for temperature, rainfall and crop yields were collected for trend analysis. Descriptive and inferential statistics were used to analyse quantitative data, content analysis was employed to analyse qualitative data. Simple linear trend analysis and Mann Kendall were used to establish trends. The findings indicate that smallholder farmers in the study area have noted …
Automated Detection Of Bilingual Obfuscated Abusive Words On Social Media Forums: A Case Of Swahili And English Texts, Geofrey Njovangwa, Godfrey Justo
Automated Detection Of Bilingual Obfuscated Abusive Words On Social Media Forums: A Case Of Swahili And English Texts, Geofrey Njovangwa, Godfrey Justo
Tanzania Journal of Science
The usage of social media has exponentially grown in recent years leaving the users with no limitations on misusing the platforms through abusive contents as deemed fit to them. This exacerbates abusive words exposure to innocent users, especially in social media forums, including children. In an attempt to alleviate the problem of abusive words proliferation on social media, researchers have proposed different methods to help deal with variants of the abusive words; however, obfuscated abusive words detection still poses challenges. A method that utilizes a combination of rule based approach and character percentage matching techniques is proposed to improve the …
Stocking Density, Growth And Survival Rate Of Post-Settled Juveniles Of Holothuria Scabra (Jaeger 1833) Reared In An Ocean-Based Floating Hapa, Yussuf S Yussuf, Saleh As Yahya
Stocking Density, Growth And Survival Rate Of Post-Settled Juveniles Of Holothuria Scabra (Jaeger 1833) Reared In An Ocean-Based Floating Hapa, Yussuf S Yussuf, Saleh As Yahya
Tanzania Journal of Science
Ocean-based nursery system using floating hapa have proved to be the best option for raising early sandfish juveniles. However, the nursery system can be further improved by providing key information that will support their application. The present study provides information on the effect of stocking density on growth and survival of sandfish juveniles reared in floating hapa (1 x 0.5 x 1 m). Three densities were tested, 100, 200 and 400 early juveniles (5 mm; 0.093 g) per hapa net in a randomized set-up. Initial density of 100 and 200 showed significant higher growth rate and final size (0.082–0.074 g/day; …
Josephson Effect In Mgb2/Pd/Nb Trilayer Josephson Junctions, Anayesu B Malisa
Josephson Effect In Mgb2/Pd/Nb Trilayer Josephson Junctions, Anayesu B Malisa
Tanzania Journal of Science
This paper reports fabrication techniques and results of MgB2/Pd/Nb trilayer Josephson junctions. The MgB2 bottom electrode was co-evaporated by molecular beam epitaxy (MBE) technique from both magnesium and boron sources at a low substrate temperature ~ 300 °C, while the interlayer and the top niobium electrode (Pd/Nb bilayer) were deposited ex-situ using RF sputtering. The junctions exhibited and Josephson effect as well as a modulation of the critical current in a magnetic field applied in a direction normal to the junction plane. Fractional and integer Shapiro steps were observed at voltages corresponding to the frequency of the applied microwave radiation …
Synthesis Of 1-(2,4-Dinitrophenyl)-3,5-Diphenyl-1h-Pyrazol-4-Ol Via Trans-1,3-Diphenyl-2,3-Epoxy-1-Propanone, Oluwaseyi B Ovonramwen
Synthesis Of 1-(2,4-Dinitrophenyl)-3,5-Diphenyl-1h-Pyrazol-4-Ol Via Trans-1,3-Diphenyl-2,3-Epoxy-1-Propanone, Oluwaseyi B Ovonramwen
Tanzania Journal of Science
The trans-1,3-diphenyl-2,3-epoxy-1-propanone was synthesized from benzaldehyde and 2-bromoacetophenone in 20 min which is more economical. The presence of ethanol and Br in 2-bromoacetophenone facilitated the reaction. The vicinal diaxial coupling constant of trans-1,3-diphenyl-2,3-epoxy-1-propanone was zero, an indication of trans configuration for a rigid 3-membered ring at ~90o dihedral angle. 1-(2,4-Dinitrophenyl)-3,5-diphenyl-1H-pyrazol-4-ol was synthesized from trans-1,3-diphenyl-2,3-epoxy-1-propanone and 2,4-dinitro phenylhydrazine in glacial CH3COOH to give 85.5% yield and characterized using FTIR, 1H, 13C NMR, DEPT 135 and MS spectra. The 1-(2,4-dinitrophenyl)-3,5-diphenyl-1H-pyrazol-4-ol can be exploited for unique biological activities and in the synthesis of synthetic fibers. Keywords: 1-(2,4-dinitrophenyl)-3,5-diphenyl-1H-pyrazol-4-ol, trans-1,3-diphenyl-2,3-epoxy-1-propanone, synthesis, 2,4-dinitro phenylhydrazine.
Effects Of Climate Changes On Water Resources: A Case Of Mindu Dam In Morogoro Municipality, Tanzania, Simon R Melchioly
Effects Of Climate Changes On Water Resources: A Case Of Mindu Dam In Morogoro Municipality, Tanzania, Simon R Melchioly
Tanzania Journal of Science
This paper presents the findings of the research conducted in Morogoro Municipality, central Tanzania. The main objective of the research was to assess the climate change impacts on water resources, taking the Mindu Dam as the case study. The study methodology involved collection, processing and analysis of both primary and secondary data. Data collection involved acquisition of Dam water level data, climate data, and Landsat 8 satellite imagery. Research findings showed that the maximum air temperature increased at a rate of 0.045% on a span of 30 years, while rainfall has been decreasing with time. Also there has been a …
Physicochemical And Bacteriological Water Quality Parameters In Relation To Land-Use Practices At A Rural Catchment, Mbinga District, Tanzania, Harieth Hellar-Kihampa, Patrick Isdory Ndunguru
Physicochemical And Bacteriological Water Quality Parameters In Relation To Land-Use Practices At A Rural Catchment, Mbinga District, Tanzania, Harieth Hellar-Kihampa, Patrick Isdory Ndunguru
Tanzania Journal of Science
Data on physicochemical water quality parameters and contamination levels is crucial for protection and sustainable utilization of water resources. This study assessed the physicochemical water quality parameters, faecal coliform bacteria and nutrient loads in water at a catchment used for municipal supply in Mbinga District, Tanzania. Samples were seasonally collected from three areas characterized by distinct geographical features, settlement patterns and land-use practices, and analyzed using standard analytical protocols. Data were subjected to paired-sampled t-test and cluster analysis. The parameters varied as follows: pH (4.75–6.83); temperature (16.4–26.2 ºC); electrical conductivity (14.6–121.1 µS/cm); total dissolved solids (7.0–23.2 mg/L); total suspended solids …
Assessment Of Groundwater Quality In Areas Surrounding Thundulu Phosphate Mine, Phalombe District, Malawi, Philip Jailos, Peter J. Chimtali, Ephraim Vunain
Assessment Of Groundwater Quality In Areas Surrounding Thundulu Phosphate Mine, Phalombe District, Malawi, Philip Jailos, Peter J. Chimtali, Ephraim Vunain
Tanzania Journal of Science
Water is one of the renewable resources essential for sustaining all forms of life and quality of drinking water is very fundamental for human health. Human activities such as mining act as sources of water contamination which consequently lead to ecological, environmental and health problems. To the best of our knowledge, no study has been conducted around the Thundulu Phosphate Mine to establish the quality of drinking water. In this regard, this study was carried out to evaluate the physico-chemical water quality parameters of areas surrounding the Thundulu Phosphate Mine in Phalombe District. Groundwater samples from the villages surrounding the …
Assessment Of Farm Households’ Vulnerability To Desertification In Rural Dry Lands Of Katsina State, Nigeria, Olanrewaju Yusuf Yahaya
Assessment Of Farm Households’ Vulnerability To Desertification In Rural Dry Lands Of Katsina State, Nigeria, Olanrewaju Yusuf Yahaya
Tanzania Journal of Science
The purpose of this study was to use a Vulnerability Index (VI) to assess farm households' vulnerability to desertification in Northern Katsina's dry land ecosystem. The specific objectives were to identify socio-economic characteristics of farm households; and determine the degree of their vulnerability to desertification. A systematic random sampling technique was used to select 633 respondents from 18 rural communities across six Local Government Areas (LGAs). Data from 21 indicators for the three components of vulnerability (exposure, sensitivity and adaptive capacity) were used to measure the degree of vulnerability and thus, classify households into less, moderate and highly vulnerable. The …
Effect Of Lowering Tube Potential And Increase Iodine Concentration Of Contrast Medium On Radiation Dose And Image Quality In Computed Tomography Pulmonary Angiography Procedure: A Phantom Study, Justin E Ngaile, Peter K Msaki, Evarist M Kahuluda, Furaha M Chuma, Jerome M Mwimanzi, Ahmed M Jusabani
Effect Of Lowering Tube Potential And Increase Iodine Concentration Of Contrast Medium On Radiation Dose And Image Quality In Computed Tomography Pulmonary Angiography Procedure: A Phantom Study, Justin E Ngaile, Peter K Msaki, Evarist M Kahuluda, Furaha M Chuma, Jerome M Mwimanzi, Ahmed M Jusabani
Tanzania Journal of Science
The aim of the study was to examine the effect of lowering tube potential and increase iodine concentration on image quality and radiation dose in computed tomography pulmonary angiography procedure. The pulmonary arteries were simulated by three syringes. The syringes were filled with 1:10 diluted solutions of 300 mg, 350 mg and 370 mg of iodine per millilitre concentration in three water-filled phantoms simulating thin, intermediate and thick patients. The phantoms were scanned at 80 kVp, 110 kVp and 130 kVp and 0.6 second rotation time using a 16 slice computed tomography (CT) scanner. The tube current was either fixed …
Mineral Liberation: A Case Study For Buzwagi Gold Mine, Alphonce Wikedzi, Thomas Leißner
Mineral Liberation: A Case Study For Buzwagi Gold Mine, Alphonce Wikedzi, Thomas Leißner
Tanzania Journal of Science
Buzwagi Gold Mine (BGM) process plant was designed such that, after secondary grinding, gold and copper are recovered by flotation. However, the flotation circuit had been inefficient, and as a result, cyanidation of flotation tailings is currently conducted to improve gold recovery. The inefficient flotation is suspected to be due to mineralogical variations of ores treated. Hence, mineral liberation characteristics of three ore blends treated by BGM were investigated by automated Scanning Electron Microscope (SEM) whereby five fractions (i.e. -1 +0.5 mm, -0.5 +0.25 mm, -0.25 +0.125 mm, -0.125 +0.063 mm and -0.063 mm) were used. It was found that …
Utilization Of Iron Filings As Partial Replacements For Sand In Self-Compacting Concrete, Simon O. Olawale, Mutiu A. Kareem, Habeeb T. Muritala, Abiola U. Adebanjo, Olusegun O. Alabi, Oluwole A. Olawuyi, Olusola O. Fadipe
Utilization Of Iron Filings As Partial Replacements For Sand In Self-Compacting Concrete, Simon O. Olawale, Mutiu A. Kareem, Habeeb T. Muritala, Abiola U. Adebanjo, Olusegun O. Alabi, Oluwole A. Olawuyi, Olusola O. Fadipe
Tanzania Journal of Science
The use of industrial by-products in concrete production is part of concerted efforts on the reduction of environmental hazards attributed to the mining of conventional aggregates. Consideration of iron filings (IF), a by-product from steel production process, is an environmentally friendly way of its disposal which is expected to yield economic concrete production. Six self-compacting concrete (SCC) mixes were made by partially substituting river sand with IF at 5%, 10%, 15%, and 20% and the mix without IF (0% IF) served as the control. The water-binder (w/b) ratio of 0.45 was adopted for all mixes. The fresh state properties of …
Analysis And Performance Evaluation Of Entropic Thresholding Image Processing Techniques For Electrical Capacitance Tomography Measurement System, Josiah Nombo, Alfred Mwambela, Michael Kisangiri
Analysis And Performance Evaluation Of Entropic Thresholding Image Processing Techniques For Electrical Capacitance Tomography Measurement System, Josiah Nombo, Alfred Mwambela, Michael Kisangiri
Tanzania Journal of Science
To improve image quality generated from the electrical capacitance tomography measurement system, the use of entropic thresholding techniques is investigated in this article. Based on the analysis of the principle of Electrical Capacitance Tomography (ECT) image reconstruction and entropic thresholding, various algorithms have been proposed for easy extraction of quantitative information from tomograms generated from the ECT system. Experiments indicate that proposed algorithms can provide high-quality images at no or minimum computational cost. It is easier to implement and integrate with classical algorithms such as Linear Back Projection, Singular value decomposition, Tikhonov regularization, and Landweber. Entropic thresholding techniques present a …
Multi-Vehicle Speed Estimation Algorithm Based On Real-Time Inter-Frame Tracking Technique, Ernest Kisingo, Ndyetabura Hamisi, Hashim U. Iddi, Baraka J. Maiseli
Multi-Vehicle Speed Estimation Algorithm Based On Real-Time Inter-Frame Tracking Technique, Ernest Kisingo, Ndyetabura Hamisi, Hashim U. Iddi, Baraka J. Maiseli
Tanzania Journal of Science
Inappropriate vehicle speeding remains a central factor that causes road accidents claiming millions of lives every year. This challenge has raised concerns for vehicle speed estimation as an attempt to promote speed enforcement methods. Traditionally, radar and lidar systems have widely been used for this purpose, despite their several shortfalls: cosine error effects, need for direct line-of-sight, and inability to simultaneously and accurately measure speed from multiple vehicles. The current work proposes an algorithm and a multi-vehicle speed estimation system in a multi-lane road environment to address multi-vehicle speed estimation shortfalls. The proposed solution exploits image processing and computer vision …
Copper Slag As A Potential Waste Filler For Polyethylene-Based Composites Manufacturing, Aleksander Hejna, Paulina Kosmela, Mateusz Barczewski, Olga Mysiukiewicz, Adam Piasecki
Copper Slag As A Potential Waste Filler For Polyethylene-Based Composites Manufacturing, Aleksander Hejna, Paulina Kosmela, Mateusz Barczewski, Olga Mysiukiewicz, Adam Piasecki
Tanzania Journal of Science
The present study aimed to analyze the application of waste material from copper production– copper slag (ŻŻL) as filler for composites based on the high-density polyethylene (HDPE). Copper slag filler was introduced in the amounts of 1–20 wt%, and its influence on the appearance (color analysis), chemical structure (Fourier-transform infrared (FTIR) spectroscopy), microstructure (optical microscopy), as well as static (tensile tests) and dynamic (dynamical mechanical analysis (DMA)) mechanical properties of composites were investigated. Proper dispersion of filler implicated that the incorporation of up to 5 wt% of filler caused only slight, 5% drop of tensile strength, with the simultaneous 16% …
Upgrading Biogas Using Eburru Zeolitic Rocks And Other Adsorbent Materials To Remove Carbon Dioxide And Hydrogen Sulphide, James K Mbugua, Joseph M Mwaniki, Damaris M Nduta, Francis B Mwaura
Upgrading Biogas Using Eburru Zeolitic Rocks And Other Adsorbent Materials To Remove Carbon Dioxide And Hydrogen Sulphide, James K Mbugua, Joseph M Mwaniki, Damaris M Nduta, Francis B Mwaura
Tanzania Journal of Science
The trace amounts of carbon dioxide and hydrogen sulfide in raw biogas lower its calorific value,cause corrosion and make it hard to compress biogas into the cylinder. Raw biogas was obtainedfrom anaerobic digestion of cow dung and market wastes. The gas was stored in tubes or urine bagbefore upgrading. Natural zeolite rocks, maize cobs, steel wire, desulphurizer, and worn-out tyreswere used as the upgrade materials. The composition of biogas was recorded before and afterupgrading using a GP180 portable biogas analyzer from Henan, China. The measured level of rawbiogas was 0.0227% H2S, >20% CO2 and 52-56% CH4. The most efficient upgrade …
Thermodynamic Analysis Of A Variable Viscosity Reactive Hydromagnetic Couette Flow Within Parallel Plates, Anthony R Hassan, Olufemi W Lawal, Funmilayo F Amurawaye
Thermodynamic Analysis Of A Variable Viscosity Reactive Hydromagnetic Couette Flow Within Parallel Plates, Anthony R Hassan, Olufemi W Lawal, Funmilayo F Amurawaye
Tanzania Journal of Science
This investigation is to consider the impact of a temperature-dependent variable viscosity of a reactive hydromagnetic Couette fluid flowing within parallel plates. The variable property of the fluid viscosity is thought to be an exponential relation of temperature under the impact of magnetic strength. The differential equations controlling the smooth movement of fluid and energy transfer are modeled and solved by using the series solution of modified Adomian decomposition technique (mADM). The outcomes are shown in tables and graphs for different estimations of thermophysical properties present in the flow regime together with the rate of entropy generation and irreversibility distribution …
Mapping Of Geological Structural Features In Lolgorien, Narok County, Kenya: Using Hillshade Analysis, Sammy O Ombiro, Akinade S Olatunji, Eliud M Mathu, Taiwo R Ajayi
Mapping Of Geological Structural Features In Lolgorien, Narok County, Kenya: Using Hillshade Analysis, Sammy O Ombiro, Akinade S Olatunji, Eliud M Mathu, Taiwo R Ajayi
Tanzania Journal of Science
Despite Lolgorien being one of the most active gold mining areas in Kenya, it is one of the most geologically understudied areas. To the best knowledge of the authors, Lolgorien geological map was last updated in the 1940s. Current technologies such as remote sensing allow new structural features such as faults to be easily identified. In this regard, this study employed remote sensed data to map structural features found in and around Lolgorien Subcounty, Narok, Kenya. This was done to identify any new structural features that might have been missed in the past. Shuttle Radar 152 Topography Mission Digital Elevation …
Coupled Effects Of Hydrophilic Nano Silica Oxide And Anatase Nano Titanium Oxide On Strengths Of Oilwell Cement, Petro E Mabeyo, Jun Gu
Coupled Effects Of Hydrophilic Nano Silica Oxide And Anatase Nano Titanium Oxide On Strengths Of Oilwell Cement, Petro E Mabeyo, Jun Gu
Tanzania Journal of Science
The life of oilwells depends on the stability of cement sheath and bond strength with the formation and casing. Extreme subsurface conditions cause substantial stresses on the cement sheath resulting in a serious impact on well integrity. The recommended API cement for oilwell fails to provide the required durability of the cemented well due to such conditions. Supplementary cementitious materials such as nanoparticles are added to improve the cement for long-lasting zonal isolation. In this study, the compressive and shear bond strengths of oilwell cement containing nano-SiO2 and nano-TiO2 were studied at 80 °C for 3, 7, 14, and 28 …
Effects Of Rapid Thermal Annealing On The Properties Of Room-Temperature Oxygenated Dc Sputtered Zinc Thin Films For Czts Solar Cells Application, Emmanuel R Ollotu, Nuru R Mlyuka, Margaret E Samiji
Effects Of Rapid Thermal Annealing On The Properties Of Room-Temperature Oxygenated Dc Sputtered Zinc Thin Films For Czts Solar Cells Application, Emmanuel R Ollotu, Nuru R Mlyuka, Margaret E Samiji
Tanzania Journal of Science
This work investigated the potential to achieve zinc oxide (ZnO) films for Cu2ZnSnS4 (CZTS) solar cells window layer at controlled annealing conditions as a potential approach to address elemental inter-diffusion in CZTS solar cells. This involved rapid thermal annealing (RTA) of room-temperature oxygenated DC sputtered zinc thin films in an ambient of nitrogen gas at different temperatures. Structural, morphological, optical, and electrical properties of these films were determined by X-ray diffractometer, Scanning Electron Microscopy, Ultraviolet-visible-near infrared spectrophotometer, and Hall Effect measurement, respectively. ZnO phases were observed after annealing the films over 150 °C. The films’ grains sizes improved with increasing …