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Mapping Of The Geological Structures Using Digital Elevation Model (Dem)-Derived Flow Direction: A Case Study Of Rungwe Volcanic Province, Southwest Tanzania, Elisante Elisaimon Mshiu
Mapping Of The Geological Structures Using Digital Elevation Model (Dem)-Derived Flow Direction: A Case Study Of Rungwe Volcanic Province, Southwest Tanzania, Elisante Elisaimon Mshiu
Tanzania Journal of Science
This study aimed to assess the potentiality of Digital Elevation Model (DEM)-derived flow direction in mapping geologic structures, specifically in areas with thick overburden of soil or volcanic materials such as in the Rungwe Volcanic Province, SW Tanzania. Clustering of flow directions based on trends of structure sets found in the study area was applied and it successfully revealed a large number of geological structures through demarcated tectonic blocks from patterns created by flow directions. Northwest–southwest (NW-SE) and NE-SW- trending lineaments are the dominant structural sets in the area whereas N-S and E-W-trending lineaments constitute the minor sets. Moreover, the …
Monodisperse Polystyrene Microspheres: Studies On The Effects Of Reaction Parameters On Particle Diameter And Colloidal Stability, Ikhazuagbe H. Ifijen, Esther U. Ikhuoria
Monodisperse Polystyrene Microspheres: Studies On The Effects Of Reaction Parameters On Particle Diameter And Colloidal Stability, Ikhazuagbe H. Ifijen, Esther U. Ikhuoria
Tanzania Journal of Science
The synthesis of highly monodisperse polystyrene (PS) microspheres via surfactant-free emulsion polymerization process was successfully carried out. Various reaction conditions such as initiator amount, monomer amount, reaction temperature and stirring speed were varied with a view to studying the effects of these polymerization parameters on the particle diameter and colloidal stability of the synthesized PS microspheres. Microscopic analysis revealed that the as-synthesized particles are spherical in shape without any form of agglomeration. Thermo-gravimetric analyzer (TGA) analysis revealed that the prepared PS sample completely degrades at 465 °C. DLS analysis showed a reduction in the average particle diameters of the as-synthesized …
Mammals Inventory Of The Kihansi River Gorge In Udzungwa Mountains, Tanzania, Dennis K. Ikanda, Samuel N. Mtoka, Mustafa Hassanali, Anna Mshanga
Mammals Inventory Of The Kihansi River Gorge In Udzungwa Mountains, Tanzania, Dennis K. Ikanda, Samuel N. Mtoka, Mustafa Hassanali, Anna Mshanga
Tanzania Journal of Science
The Kihansi gorge montane forest in Udzungwa Mountains forms part of the Eastern Arc Mountains (EAM) which contain some of the most biologically diverse and endemic montane ecosystems in all of Africa. The Kihansi river gorge was opened up for hydroelectric development in the late 1990s, attracting hundreds of farming communities whose activities lead to environmental degradation and hence presumed biodiversity loss in the montane forest which is not understood. Using camera traps, an inventory of mammals of the area was conducted for 24 consecutive days. About 14 mammal species were photo captured, indicating diverse assemblage of large and medium …
Crop Pests, Control Measures And Potential Impacts In Kihansi Catchment Area, Beatrice Pallangyo, K. Mdily, C. Mkondo, A. Kibola
Crop Pests, Control Measures And Potential Impacts In Kihansi Catchment Area, Beatrice Pallangyo, K. Mdily, C. Mkondo, A. Kibola
Tanzania Journal of Science
A baseline survey which covered 349 households in Bomang’ombe and Masisiwe (Kilolo district), Kibengu and Mapanda (Mufindi district) and Chita and Chisano (Kilombero district) was conducted to identify major pests, control measures and potential impacts in Kihansi catchment area. Maize was the most predominant crop being cultivated by 55% of the total respondents in all the study districts. Pests and diseases were the major constraints to crop production, whereby cereal stem borers were the most serious pests being reported by 88.2% of respondents. Application of synthetic pesticides was the major pest control measure, being applied by 66% of the respondents. …
Understorey Bird Communities 8 And 18 Years After River Diversion In Kihansi Gorge, Udzungwa Mountains In The Eastern Arc Mountains, Tanzania, Chacha Werema, Charles A. Msuya
Understorey Bird Communities 8 And 18 Years After River Diversion In Kihansi Gorge, Udzungwa Mountains In The Eastern Arc Mountains, Tanzania, Chacha Werema, Charles A. Msuya
Tanzania Journal of Science
On the most south-western slopes of the Udzungwa Mountains in Tanzania lies Kihansi River. The river was diverted underground in 2000 to run electric turbines for electricity generation. Using mist netting, pre-diversion (in 1998 and 1999) and short term post-diversion (in 2001) effects of the river diversion on understorey birds were undertaken before and year after river diversion, respectively. Intermediate and long-term effects of river diversion on understorey birds at the same transects are non-existent. In September 2008 and August and September 2018, using mist nets, birds were surveyed at the same transects to assess whether or not there have …
The Dynamics Of Re-Introduced Kihansi Spray Toad Nectophrynoides Asperginis And Other Amphibians In Kihansi Gorge, Udzungwa Mountains, Tanzania, Wilirk Ngalason, Cuthbert L. Nahonyo, Charles A. Msuya
The Dynamics Of Re-Introduced Kihansi Spray Toad Nectophrynoides Asperginis And Other Amphibians In Kihansi Gorge, Udzungwa Mountains, Tanzania, Wilirk Ngalason, Cuthbert L. Nahonyo, Charles A. Msuya
Tanzania Journal of Science
The dynamics of the reintroduced Kihansi spray toad Nectophrynoides asperginis and other amphibian species that occur in the Kihansi gorge, Udzungwa Mountains were studied. The area is a home for the endemic toad that became extinct before individuals bred in captivity were reintroduced. Previous studies on the biology of amphibians conducted in the gorge focused on a few aspects but none has dealt with the dynamics of both the reintroduced Kihansi spray toad (KST) and other amphibians. Information on species richness and the abundance of amphibian species occurring in the gorge have not been dealt with in depth. Time-constrained audio-visual …
Land Cover Change Detection In The Urban Catchments Of Dar Es Salaam, Tanzania Using Remote Sensing And Gis Techniques, Philip Mzava, Joel Nobert, Patrick Valimba
Land Cover Change Detection In The Urban Catchments Of Dar Es Salaam, Tanzania Using Remote Sensing And Gis Techniques, Philip Mzava, Joel Nobert, Patrick Valimba
Tanzania Journal of Science
In this study, the Maximum Likelihood (ML) classification, Normalized Difference Vegetation Index (NDVI) and Artificial Neural Network (ANN) methods were applied to three (3) Landsat images collected over time (1979, 1998 and 2014), that contained historical land cover features for the urban catchments of Dar es Salaam. Five major land cover classes were identified, mapped, and the land cover changes investigated. The major land cover changes observed from post-classification comparisons of the classified images are: the forest land losing 17.09% of its area in the period 1979-1998 to other land covers, mainly turning to grassland, and from 1998 to 2014, …
Target-To-Target Interaction In Through-The-Wall Radars Under Path Loss Compensated Multipath Exploitation-Based Signal Model For Sparse Image Reconstruction, Emmanuel K. Kokumo, Baraka Maiseli, Abdi T. Abdalla
Target-To-Target Interaction In Through-The-Wall Radars Under Path Loss Compensated Multipath Exploitation-Based Signal Model For Sparse Image Reconstruction, Emmanuel K. Kokumo, Baraka Maiseli, Abdi T. Abdalla
Tanzania Journal of Science
Multipath caused by reflections from interior walls of buildings has been a long-standing challenge that affects through-the-wall radar imaging. Multipath creates ghost images that introduce confusion when detecting desired targets. Traditionally, multipath exploitation techniques under the compressive sensing framework have widely been applied to address the challenge. However, the multipath component emanating from target-to-target interactions has not been considered–a consequence that may, under multiple target scenarios, lead to incorrect image interpretation. Besides, far targets experience more attenuation due to free space path loss, hence resulting into target undetectability. This study proposes a signal model, based on multipath exploitation techniques, by …
On Scalar Multiples Of Hypercyclic Operators On Non-Normable And Separable Fréchet Spaces, Melkiory M. Aloyce, Santosh Kumar, Marco Mpimbo
On Scalar Multiples Of Hypercyclic Operators On Non-Normable And Separable Fréchet Spaces, Melkiory M. Aloyce, Santosh Kumar, Marco Mpimbo
Tanzania Journal of Science
In this paper, we proved that if F is a non-normable and separable Fréchet space without a continuous norm, then there exists an operator T L (F) such that λ T is hypercyclic for any λ {0} of modulus 1 and has similar set of hypercyclic vectors as T. An illustrative example to the main theorem is also provided.
Climate Change Increasing Threats On Non-Conserved Mangroves Forests Of Micheweni, Zanzibar–Tanzania, Haji M. Hamad, Islam S.S. Mchenga, Mariam I. Hamisi
Climate Change Increasing Threats On Non-Conserved Mangroves Forests Of Micheweni, Zanzibar–Tanzania, Haji M. Hamad, Islam S.S. Mchenga, Mariam I. Hamisi
Tanzania Journal of Science
Overutilization of mangroves has been reported as the factor for mangrove declining across the globe. However, currently, the global climate change has been claimed to pose significant threats to the survival of mangroves. This study analysed the impacts of climatic variability (sea level rise, temperature and precipitation) to the mangroves of Micheweni (non reserve) and Ngezi-Vumawimbi (nature forest reserve). Multi-disciplinary approach was employed to collect information on community perceptions. Secondary time series data of up to 30 years for temperature, rainfall and sea level rise were collected and analysed. Inquiry results on how local communities perceived climate change showed that …
Mixed Mode Device-To-Device Communication Scheme For Congestion Reduction And Channel Usage Optimization In 5g Cellular Networks, Chiza M. Christophe, Omar F. Hamad, Libe V. Massawe, Abdi T. Abdalla
Mixed Mode Device-To-Device Communication Scheme For Congestion Reduction And Channel Usage Optimization In 5g Cellular Networks, Chiza M. Christophe, Omar F. Hamad, Libe V. Massawe, Abdi T. Abdalla
Tanzania Journal of Science
Device-to-Device (D2D) communication schemes have gained more attention in cellular networks particularly in normalization process of the upcoming 5G networks. They have been investigated in core network offloading, congestion reduction and channel usage optimization. The two last cases are among the major constraints in current cellular networks and are the main concerns of this paper. The paper presents a mixed mode D2D communication scheme to decentralize data collection between devices and the base station in order to reduce the number of direct connections at the base station of ultra-dense cells characterized by different levels of channel utilizations or target data …
Preliminary Palynology Of The Karoo Equivalent Tanga Beds, Coastal Tanzania: Insights On Preservation, Age And Depositional Environments, Stephen Peter Magohe
Preliminary Palynology Of The Karoo Equivalent Tanga Beds, Coastal Tanzania: Insights On Preservation, Age And Depositional Environments, Stephen Peter Magohe
Tanzania Journal of Science
The major challenge to the current understanding of the stratigraphy of the Tanga Basin is scarcity of biostratigraphy age-control data. A number of palynomorphs retrieved from core samples of the Tanga Beds and analysed for palynology are here presented. These include bisaccate pollen grains belonging to the Alisporites-Falcisporites complex, making about 55% average of the total assemblage. The rest of the assemblage comprises other palynomorphs (pollen and spores) and phytoclasts. The miospores documented from the studied samples have poor to fairly good preservation; the organic residues (non-pollen palynomorphs) are excellently preserved. Based on palynologic evidences, and the presence of fossil …
Quantitative Assessment Of Resistivity Anisotropy In Evaluation Of Laminated Shaly Sand Hydrocarbon Reservoirs–A Case Study In The Barents Sea, Norway, Ernest S. Mulaya
Quantitative Assessment Of Resistivity Anisotropy In Evaluation Of Laminated Shaly Sand Hydrocarbon Reservoirs–A Case Study In The Barents Sea, Norway, Ernest S. Mulaya
Tanzania Journal of Science
Resistivity anisotropy in shaly sand lamination sequences affects the hydrocarbon evaluation in multiple dimensions of petrophysical logs. Currently, vertical resistivity (Rv) and horizontal resistivity (Rh) from 3D triaxial induction measurements can be applied simultaneously to resolve these petrophysical impacts. In this paper, an extensive analysis is offered with a focus on the hydrocarbon evaluation based on advanced petrophysical logs from a well. A critical analysis is done on the three comparable cases including clean formation as a base case, shaly sand case and laminated shaly sand case towards resolving resistivity anisotropy in a typical shaly sand laminated reservoir. The analysis …
An Investigation Of The Potentials Of 2-[(2-Hydroxyphenyl) Methylidene] Hydrazine-1-Carbothioamide And Its Mn(Ii) And Zn(Ii) Complexes As Antimicrobial Agents, Umar Sani, Musbahu Yahaya, Dailami S. Adam
An Investigation Of The Potentials Of 2-[(2-Hydroxyphenyl) Methylidene] Hydrazine-1-Carbothioamide And Its Mn(Ii) And Zn(Ii) Complexes As Antimicrobial Agents, Umar Sani, Musbahu Yahaya, Dailami S. Adam
Tanzania Journal of Science
Antibiotic resistance as a result of misuse, overuse or abuse of drugs is an issue of serious concern world over. The quest for more active and robust antimicrobial agents remains a scientific challenge and requires multimillion-dollar investment in the area of drug design and development. Here in, we report the synthesis and characterisation of a tridentate thiosemicarbazone (2-[(2-hydroxyphenyl)methylidene]hydrazine-1-carbothioamide) (HL) from salicylaldehyde and thiosemicarbazide. Its complexes with Mn(II) and Zn(II) were prepared following similar technique and characterised by melting point, FT-IR, UV –visible spectrophotometry, and elemental analysis. The Mn(II) complex showed paramagnetism with a magnetic moment value of 5.80 BM while …
Synthesis Of Semiochemicals And Related Fine Chemicals From Cashew Nut Shell Liquid, Godfrey Pius, Quintino A Mgani
Synthesis Of Semiochemicals And Related Fine Chemicals From Cashew Nut Shell Liquid, Godfrey Pius, Quintino A Mgani
Tanzania Journal of Science
This paper reports on syntheses of 3-hydroxybenzaldehyde (1) and tetradecanal (2) from the same renewable starting material (cashew nut shell liquid or CNSL), thus demonstrating the potential of the agro-waste cashew nut shells (CNS) as a source of valuable fine and industrial chemicals. The strategy employed in accomplishing the synthesis started with extraction of CNSL followed by isolation of anacardic acid (4) and decarboxylation to give cardanol (5). Compound 5 was hydrogenated followed by protection of phenolic group to give 3-pentadecylphenyl acetate (7). Benzylic oxidation of compound 7 followed by reduction and dehydration resulted into formation of 3-(pentadec-1-en-1-yl)phenol (9). Ozonolysis …
Generation Of Highly Ordered 3d Vivid Monochromatic Coloured Photonic Crystal Films Using Evaporative Induced Technique, Ikhazuagbe H. Ifijen, Esther U. Ikhuoria
Generation Of Highly Ordered 3d Vivid Monochromatic Coloured Photonic Crystal Films Using Evaporative Induced Technique, Ikhazuagbe H. Ifijen, Esther U. Ikhuoria
Tanzania Journal of Science
Structural coloured crystal films have attracted immense attention because of numerous applications like optical sensing, anti-counterfeiting and photonic fabrics. Herein, we successfully generated highly periodic three-dimensional (3D) monochromatic structural crystal films with brown, turquoise, blue and yellow colourations from as-synthesized poly(styrene-methyl methacrylate-acrylic acid) or P(St-MMA-AA) colloidal latex via the evaporative induced self-assembly technique. The colours were controlled through the modulation of their crystal lattice by varying their microspheres diameter from 180 nm, 120 nm, and 260 nm to 150 nm. Scanning electron microscope and atomic force microscope (SEM/AFM) analyses showed that the photonic crystal particles readily assembled into an impeccable …
Improved Hybrid Blind Papr Reduction Algorithm For Ofdm Systems, Kwame Ibwe
Improved Hybrid Blind Papr Reduction Algorithm For Ofdm Systems, Kwame Ibwe
Tanzania Journal of Science
The ever growing demand for high data rate communication services has resulted into the development of long-term evolution (LTE) technology. LTE uses orthogonal frequency division multiplexing (OFDM) as a transmission technology in its PHY layer for down-link (DL) communications. OFDM is spectrally efficient multicarrier modulation technique ideal for high data transmissions over highly time and frequency varying channels. However, the transmitted signal in OFDM can have high peak values in the time domain due to inverse fast Fourier transform (IFFT) operation. This creates high peak-to-average power ratio (PAPR) when compared to single carrier systems. PAPR drives the power amplifiers to …
Microstructure And Materials Characterization Of Sol-Gel Synthesized Zro2 Systems, Sungsoo Park, Godlisten Shao
Microstructure And Materials Characterization Of Sol-Gel Synthesized Zro2 Systems, Sungsoo Park, Godlisten Shao
Tanzania Journal of Science
The roles of pH and thermal treatment on the microstructures of sol-gel synthesized mesoporous ZrO2 systems have been investigated. In order to control the crystal structures and particle sizes of the final products, the pH values of the reaction mixtures were controlled between 5 and 12 followed by calcination at temperatures ranging from 450 to 1000 °C. The microstructures of the zirconia systems were then examined by XRD, TEM, TGA, UV-visible DRS and nitrogen physisorption study analyses. It was found that pH values and calcination temperatures have significant influence on the crystallization temperature, phase transformation and particle size of the …
Decision Rules For Supplier Selection Using Intuitionistic Fuzzy Topsis, Dickson Omorogbe, Sunday Omosigho
Decision Rules For Supplier Selection Using Intuitionistic Fuzzy Topsis, Dickson Omorogbe, Sunday Omosigho
Tanzania Journal of Science
This paper provides a methodology for addressing contradictions in the ranking of suppliers when more than one metric functions are adopted in intuitionistic fuzzy TOPSIS (Technique for Order Preference by Similarity to the Ideal Solution) for supplier selection. Our literature search revealed contradictions when more than one metric functions are adopted in the method. Two types of contradictions were addressed: (i) contradiction of the best supplier, and (ii) contradiction at the middle of the park. Decision rules algorithms were developed to address the problems.Worked examples were given to illustrate the rules for resolving the contradiction. A major thrust of this …
Geological Modeling Of Hydrocarbon Reservoir Rocks In The Mafia Basin, Offshore Tanzania, Bahati Mohamed, Elisante Mshiu, Ernest Mulaya
Geological Modeling Of Hydrocarbon Reservoir Rocks In The Mafia Basin, Offshore Tanzania, Bahati Mohamed, Elisante Mshiu, Ernest Mulaya
Tanzania Journal of Science
This study presents a 3D geological model of reservoir rocks in the Mafia Basin based on interpretation of 2D seismic and well data towards understanding the hydrocarbon prospectivity. 2D seismic data were used to generate surface maps and therefore the subsurface configuration of the reservoir complemented with petrophysical analysis to determine lithology and reservoir properties. Structural and petrophysical properties modeling were distributed stochastically within the constructed 3D grid using Sequential Indicator Simulation (SIS) and Gaussian Random Function Simulation (GRFS) algorithms. Results from well log analysis and petrophysical models classify the reservoir under a moderate reservoir quality with 19% to 20% …
Assessment Of The Effect Of Acid Activation Of Kaolin From Malangali On Water Defluoridation, Hosea Shuma, Lupituko Mkayula, Yahya Makame
Assessment Of The Effect Of Acid Activation Of Kaolin From Malangali On Water Defluoridation, Hosea Shuma, Lupituko Mkayula, Yahya Makame
Tanzania Journal of Science
Malangali kaolin clay was activated by means of an acid for defluoridation studies. The Acid Activated Malangali Kaolin (AAMK) clay and the Untreated Malangali Kaolin (UMK) were both characterized using spectroscopic and adsorption techniques. BET analysis of AAMK and UMK showed that both clays have mesoporosity characteristics with surface areas ranging from 55 to 58 m2/g. Spectroscopic studies showed that in both clays the major mineral forms are kaolinites and albites with high amounts of SiO2 and Al2O3. AAMK and UMK are endowed with surface functional groups such as OH, Si–O–Si, and Al–O–Al all of which being suitable for adsorption …
Densification Behaviour And Structural Properties Of Niobium And Lanthanum-Doped Lead Zirconate Titanate And Lead Barium Zirconate Ferroelectrics For Low-Donor Dopants Concentrations, David Bahati, Ismael Makundi
Densification Behaviour And Structural Properties Of Niobium And Lanthanum-Doped Lead Zirconate Titanate And Lead Barium Zirconate Ferroelectrics For Low-Donor Dopants Concentrations, David Bahati, Ismael Makundi
Tanzania Journal of Science
In this paper we report the densification behaviour and structural properties of niobium and lanthanum-doped lead zirconate titanate (PZT) and lead barium zirconate (PBZ) ferroelectrics for low additive concentrations (0–2%). The PZT materials were calcined at 800 °C and sintered at 1200 °C while the PBZ materials were calcined at 850 °C and sintered at 1250 °C. Densification behaviour revealed that materials with lanthanum or niobium additives of greater than 0.5% for PZT and 0.2% for PBZ achieved complete densification. A strong distortion was observed in lattice parameters for lower dopants in which PBZ doped materials showed higher lattice distortions …
Multivariate Assessment Of Metal Contamination In Mtoni Sedimentary Environment, Tanzania, Matobola Mihale
Multivariate Assessment Of Metal Contamination In Mtoni Sedimentary Environment, Tanzania, Matobola Mihale
Tanzania Journal of Science
Enrichment factor, geo-accumulation factor, contamination factor, degree of contamination, modified degree of contamination and potential contamination index were applied to assess the contamination of metals (Al, Cr, Mn, Fe, Ni, Cu, Zn, As, Cd and Pb ) in the Mtoni estuary sediments in Dar es Salaam, Tanzania. The sediment samples were sampled as appropriate, treated using established methods and analysed using inductively coupled plasma-high resonance mass spectrometry. The calculated enrichment factor values indicated contamination varying from minor (EF > 1) to severe contamination (EF > 50). The determined geo-accumulation index, contamination factor, degree of contamination, modified degree of contamination and potential contamination …
Evaluation Of The Influence Of Additional Beam Filtration On Image Quality And Patient Dose In X-Ray Fluoroscopy Procedures, Justin Ngaile, Peter Msaki, Ramadhani Kazema, Jerome Mwimanzi, Mechris Mango
Evaluation Of The Influence Of Additional Beam Filtration On Image Quality And Patient Dose In X-Ray Fluoroscopy Procedures, Justin Ngaile, Peter Msaki, Ramadhani Kazema, Jerome Mwimanzi, Mechris Mango
Tanzania Journal of Science
The aim of the study was to evaluate the influence of additional filtration on radiation dose and image quality for patients during hysterosalpingography (HSG) and retrograde urethrography (RUG) procedures. The influence of filtering on image quality for each phantom thickness was made using a combination of different filter thicknesses. Entrance surface air kerma (ESAK) rates to Perspex phantom were measured using a solid state detector for various added combination of filter materials. Fluoroscopic image contrast was assessed using a Leeds TOR-18FG test object with a range of filter materials and phantom thicknesses. Phantom studies demonstrated that the use of additional …
Performance Of A Customized Cryo-Cooling System Designed For The Measurement Of The Lifetime Of Nuclear Excited States At Cryogenic Temperatures, Innocent J. Lugendo
Performance Of A Customized Cryo-Cooling System Designed For The Measurement Of The Lifetime Of Nuclear Excited States At Cryogenic Temperatures, Innocent J. Lugendo
Tanzania Journal of Science
Theoretical predictions that the lifetime of nuclear excited states can be varied if the nucleus is subjected to a condition that allows multiple coherent emission and re-absorption of gamma photons by the nucleus is of much interest to the nuclear physicists. Therefore, an experiment has been designed to study the possibility of lifetime variation. Based on the theory requirements, lifetime variations can be observed when the nucleus is cooled to cryogenic temperatures. Both the cryo-cooling system and the fast timing system have been developed. In the current work, the design, operation and performance of the developed cryo-cooling system is discussed. …
Statistical Analysis Of Ambient Conditions And Water Temperature On Standard Achievement Of Volume Calibration Of Small Laboratory Glassware, Lazaro Revocatus, Nyimvua Shaban, Isambi S. Mbalawata
Statistical Analysis Of Ambient Conditions And Water Temperature On Standard Achievement Of Volume Calibration Of Small Laboratory Glassware, Lazaro Revocatus, Nyimvua Shaban, Isambi S. Mbalawata
Tanzania Journal of Science
Volumetric apparatus calibration is a very sensitive matter in metrological institutions. Identification and evaluation of the uncertainty factors affecting volume calibration of volumetric apparatus such as small laboratory glassware is a critical issue to investigate in order to increase accuracy in calibration.This studyinvestigates the contributions of ambient conditions and water temperature in volume calibration of small laboratory glassware. The study used existing empirical data from the Tanzania Bureau of Standards.The multiple linear regression modelwas used to establish better relationship between explanatory variables and response variable. The model analyzedthree predictor variables namely ambient temperature, pressure and relative humidity. Water temperature was …
Status Updates On Plastics Pollution In Aquatic Environment Of Tanzania: Data Availability, Current Challenges And Future Research Needs, Dativa J. Shilla
Status Updates On Plastics Pollution In Aquatic Environment Of Tanzania: Data Availability, Current Challenges And Future Research Needs, Dativa J. Shilla
Tanzania Journal of Science
Plastics are the most useful materials invented by man, and have brought great convenience to our daily lives but not without problems. Inappropriate disposal of wasted plastics has caused serious environmental problems. Over the past decade, microplastic debris in both marine and freshwater systems have become an emerging issue. A literature review was conducted to summarize the current state of knowledge of plastic pollution in Tanzanian aquatic systems. Although, Tanzania has vast coastlines and world’s largest freshwater lakes, the extent of microplastics presence in the aquatic environment remains largely unreported. Data from volunteer beach cleanups in Dar es Salaam areas …
Assessment Of Oyster Mushroom Production And Profitability In Harare Urban Andperiurban Areas (Ruwa), Zimbabwe, Memory Mutema, Kiswell Basira, Dexter Savadye, Wilson Parawira
Assessment Of Oyster Mushroom Production And Profitability In Harare Urban Andperiurban Areas (Ruwa), Zimbabwe, Memory Mutema, Kiswell Basira, Dexter Savadye, Wilson Parawira
Tanzania Journal of Science
The study is an evaluation of the profitability of oyster mushroom production by small scale producers in urban and peri-urban settings with particular attention on trends in production and revenue during the period of 2014–2017. The Net Present Value (NPV), Discount rate and Benefit Cost Ratio (BCR) and Internal Rate of Return (IRR) were used to evaluate profitability. The average values of NPV, BCR and IRR for the year 2014–2017 were 13036.46, 15.75 and 141.42%, respectively. These values show that mushroom production has been very profitable during the period. Furthermore, production decreased between 2014 and 2015 before rising exponentially from …
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
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
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 …