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A Comparative Study Of Species Diversity Of Migrant Birds Between Protected And Unprotected Areas Of The Hadejia-Nguru Wetlands, Nigeria, As Ringim, Fj Magige, Rm Jasson
A Comparative Study Of Species Diversity Of Migrant Birds Between Protected And Unprotected Areas Of The Hadejia-Nguru Wetlands, Nigeria, As Ringim, Fj Magige, Rm Jasson
Tanzania Journal of Science
Among the most complex and fascinating behaviour in birds is their long, non-stop migration. Despite Hadejia-Nguru Wetlands (Ramsar site) being an important wintering ground for migratory birds, little is known about the diversity while density is completely lacking. This study assessed the status of migratory birds in the wetland’s Protected Areas (PAs) and Unprotected Areas (UPAs). A total of 99 census points spaced 400 m apart with radius of 100 m were surveyed from 14 wetlands (48 point count stations in the PAs and 51 in the UPAs). A total of 54 migrant bird species belonging to 13 orders and …
Conservation Efforts Of Kihansi Spray Toad Nectophrynoides Asperginis: Its Discovery, Captive Breeding, Extinction In The Wild And Re-Introduction, Cuthbert Nahonyo, Ezekiel Goboro, Wilirk Ngalason, Severinus Mutagwaba, Ichard Ugomba, Mohammed Nassoro, Emmanuel Nkombe
Conservation Efforts Of Kihansi Spray Toad Nectophrynoides Asperginis: Its Discovery, Captive Breeding, Extinction In The Wild And Re-Introduction, Cuthbert Nahonyo, Ezekiel Goboro, Wilirk Ngalason, Severinus Mutagwaba, Ichard Ugomba, Mohammed Nassoro, Emmanuel Nkombe
Tanzania Journal of Science
Species conservation depends on the initiatives to restore or retain and sustainably use the environment in which the species live. This paper highlights how development projects can affect biodiversity conservation and the challenges in achieving sustainable development. The paper discusses a case study of the Kihansi Spray Toad (KST) (Nectophrynoides asperginis) from its discovery, extinction in the wild, captive breeding and subsequent reintroduction to its native habitat; focusing on events, challenges, approaches in addressing issues, future prospects and achievements in the conservation of this endemic species. There has been considerable success in KST husbandry in captivity and reintroduction trials of …
Effect Of Natural Blue-Green Algal Cells Lysis On Freshwater Quality, Kessy Kilulya, Titus Msagati, Bhekie Mamba
Effect Of Natural Blue-Green Algal Cells Lysis On Freshwater Quality, Kessy Kilulya, Titus Msagati, Bhekie Mamba
Tanzania Journal of Science
Blue-green algae grow in freshwater bodies when they are provided with suitable factors such as nutrients and appropriate weather conditions. Their cell lysis occurs naturally when they encounter unfavourable conditions. This study reports on the types and amounts of fatty acids added into freshwater due to the algal cell lysis. The investigation on the amount of fatty acids released into water due to algal cells lysis was performed by placing samples in two compartments, one with no light allowing the algae cells to die while the other compartment was kept in favourable conditions enough to sustain the life of algae. …
Nuclear Analytical Techniques In Tanzania: A Review, Yusufu Koleleni
Nuclear Analytical Techniques In Tanzania: A Review, Yusufu Koleleni
Tanzania Journal of Science
It has been a tradition to perceive that Nuclear/Atomic radiations are only related to Nuclear/Atomic bombs, heavy ammunitions and consequently applications for human and non-peaceful destructions. In this paper the questions on how the Nuclear/Atomic radiations may be used for peaceful applications and specifically to Tanzanian situations are presented. Methods like Energy Dispersive X-Ray fluorescence (EDXRF), Particle Induced X-Ray Emission (PIXE), Electron probe Micro-Mass Analysis (EPMA), Neutron Activation Analysis (NAA) for investigations of different types of samples in geology; environmental, medical, biological and chemical are discussed.
Levels Of Formaldehyde And Acetaldehyde In Selected Bottled Drinking Water Sold In Urban Areas In Tanzania, Esther H.J. Lugwisha, John A.M. Mahugija, Christopher Mwankuna
Levels Of Formaldehyde And Acetaldehyde In Selected Bottled Drinking Water Sold In Urban Areas In Tanzania, Esther H.J. Lugwisha, John A.M. Mahugija, Christopher Mwankuna
Tanzania Journal of Science
The levels of formaldehyde and acetaldehyde in bottled drinking water and the effect of storage time and storage conditions on their levels were determined. A total of 144 samples of six brands of bottled drinking water were purchased from Dar es Salaam, Iringa, Mwanza and Arusha regions in Tanzania. Analysis was performed using HPLC on the 1st day and after 14 and 42 days of storage in a refrigerator, at room temperature and exposure to sunlight. The levels of formaldehyde and acetaldehyde in the refrigerated samples ranged from 2.46 to 19.25 μg/L and from not detected (ND) to 58.70 μg/L, …
Naturally Occurring Mellein-Type 3,4-Dihydroisocoumarins And Related Lactones: Synthetic Approaches - A Review, Stephen Jm Mdachi
Naturally Occurring Mellein-Type 3,4-Dihydroisocoumarins And Related Lactones: Synthetic Approaches - A Review, Stephen Jm Mdachi
Tanzania Journal of Science
Mellein and its derivatives are the most common 3,4-dihydroisocoumarins and are known to exhibit an array of biological activities such as antibacterial, antifungal, antimalarial, antiallergic, antitumor, anti-inflammatory, antiulcer, pheromonal, plant growth-promoting and antileukemic activities. Other mellein derivatives are recognized phytotoxins, neurotoxins, hepatotoxins, nephrotoxins and teratogens. Consequently, considerable efforts have been directed at studying these natural products. While most of the reported studies have focused on the isolation, characterization and bioassay studies of melleins, a number of synthetic studies have also been reported. This paper focuses on synthetic approaches towards these biologically active and, thus, potentially useful natural products. The aim …
Petrographic And Geochemical Characteristics Of The Kiejo, Rungwe And Ngozi Volcanic Rocks, Southern Tanzania: Implication For Tectonic Activities And Magmatic Differentiation, Athanas S. Macheyeki
Petrographic And Geochemical Characteristics Of The Kiejo, Rungwe And Ngozi Volcanic Rocks, Southern Tanzania: Implication For Tectonic Activities And Magmatic Differentiation, Athanas S. Macheyeki
Tanzania Journal of Science
Rock samples were collected from the Kiejo, Rungwe and Ngozi volcanoes, southern Tanzania. Results show that, in the Ngozi and Rungwe volcanoes, magma cooled relatively fast. After large part of the magma had crystallized, nucleation of crystals at a relatively slow rate crystallized from interstitial fluids of the primary magma that had already crystallized fine grained minerals resulting into large grains of minerals. In the Kiejo volcano, both zoned and unzonned olivine crystals exist; unzoned crystals being primary and the zoned ones are secondary. Such observations also indicate that the magma responsible for these rocks had interstitial fluids that crystallized …
Identification Of Tanzanian Saprophytic Edible Mushrooms By Amplification And Sequencing Of Its/Lsu Regions Of Ribosomal Rna Operon, Ibrahim Juma, Anthony Manoni Mshandete, Donatha Damiani Tibuhwa, Amelia Kajumulo Kivaisi
Identification Of Tanzanian Saprophytic Edible Mushrooms By Amplification And Sequencing Of Its/Lsu Regions Of Ribosomal Rna Operon, Ibrahim Juma, Anthony Manoni Mshandete, Donatha Damiani Tibuhwa, Amelia Kajumulo Kivaisi
Tanzania Journal of Science
In this study, ten wild saprophytic edible mushrooms samples, collected from Tanzania natural forests and planted trees, and their two domesticated forms were characterized by in-vitro/in-vivo amplification and sequencing of ITS/LSU regions. Mushroom genomic DNA was extracted by ZR Fungal/Bacterial DNA MniPrep Kit. ITS and LSU regions were amplified using ITS-4/ITS-5 and LR16/LROR primers, respectively and sequenced. The amplicons with messy sequences were cloned. For analyzing recombinant E. coli DH5α cells, colony PCR and sequencing were done using M13-F/M13-R primers. The studied mushrooms were identified as Amylosporus sp. IJ-2014, Polyporales sp., Polyporus tenuiculus, Pleurotus cystidiosus, Laetiporus sp. IJ-2014, Lentinus sajor-caju, …
Performance Of Water Filters Towards The Removal Of Selected Pollutants In Arusha, Tanzania, Beatrice Kiagho, Revocatus Machunda, Askwar Hilonga, Karoli N. Njau
Performance Of Water Filters Towards The Removal Of Selected Pollutants In Arusha, Tanzania, Beatrice Kiagho, Revocatus Machunda, Askwar Hilonga, Karoli N. Njau
Tanzania Journal of Science
This paper presents the findings of a study carried out to investigate the efficiency of selected common water filters in the removal of Escherichia coli, organic matter and fluoride. Additionally, the Total Suspended Solids, Turbidity and colour were also considered for assessing the performance of the filters in ensuring safe water provision. The results showed that various filters performed differently at particular retention times. Removal of Escherichia coli, was found to be 100%, 75%, 96%, 96.5, 98.5%forbio-sand, slow sand, ceramic, bone char and membrane purifier respectively. Organic matter removal was found to be 47%, 43%, 53%, 43.4% for bio-sand, slow …
Spread Of Tylodelphys Mashonense (Digenea: Diplostomidae) By Grey Heron Ardea Cinerea And Great White Egret A. Alba In Lake Victoria, Tanzania, Fred D. Chibwana, Gamba Nkwengulila
Spread Of Tylodelphys Mashonense (Digenea: Diplostomidae) By Grey Heron Ardea Cinerea And Great White Egret A. Alba In Lake Victoria, Tanzania, Fred D. Chibwana, Gamba Nkwengulila
Tanzania Journal of Science
Despite the fact that Tylodelphys mashonense, parasites of the cranial cavity of the catfish Clarias gariepinus, are ubiquitous in freshwater systems, little is known on their spread. As such, we examined a total of 152 piscivorous birds, belonging to 6 species; 43 great cormorant Phalacrocorax carbo, 33 grey heron Ardea cinerea, 26 hamerkop Scopus umbretta, 22 great white egret Ardea alba, 15 marabou stork Leptoptilos crumeniferus and 13 pied kingfisher Ceryle rudis foraging in the Lake Victoria. Out of the six bird species only A. cinerea and A. alba were found infected by T. mashonense with prevalence of 42.4% and …
Variation Of Small Mammal Populations Across Different Habitat Types In The Serengeti Ecosystem, Flora J Magige
Variation Of Small Mammal Populations Across Different Habitat Types In The Serengeti Ecosystem, Flora J Magige
Tanzania Journal of Science
This study investigated the abundance and diversity of small mammals in cultivated land (unprotected area) and wooded grassland in the Serengeti National Park (protected area) in the Serengeti ecosystem. Small mammal populations were sampled through capture-mark-recapture trapping techniques in March-April 2010. A total of 896 trap nights covering wet season, 9 species of rodents and 1 species of soricomorphs (shrew family) were captured. Overall, Multimammate rat Mastomys natalensis (Smith) was by far the most abundant rodent in cultivated land (28%) while inside the park, shrew Crocidura sp., was high in numbers (8%). A significantly higher abundance (trap success) of small …
Assessment Of Dairy Wastewater Treatment And Its Potential For Biogas Production At Tanga Fresh Limited, Anna S. Nyaki, Karoli N. Njau
Assessment Of Dairy Wastewater Treatment And Its Potential For Biogas Production At Tanga Fresh Limited, Anna S. Nyaki, Karoli N. Njau
Tanzania Journal of Science
The extent of pollution of dairy wastewater treated in a septic tank and its potential for biogas production was investigated. Performance of the existing treatment system was assessed through characterization of both raw and treated effluents. From the analysis parameters like Chemical Oxygen Demand (COD), Biochemical Oxygen Demand (BOD5), Total Suspended Solids (TSS), alkalinity, turbidity, color and phosphorus disclosed inadequate system performance with treated effluent displaying higher values of organic matter than the allowed discharge limits according to the national standards. Optimal conditions for biogas production such as temperature, pH and type of inoculum were determined through batch experiments. The …
Ligninolytic Enzymes Of The Fungus Isolated From Soil Contaminated With Cow Dung, Rose J. Masalu
Ligninolytic Enzymes Of The Fungus Isolated From Soil Contaminated With Cow Dung, Rose J. Masalu
Tanzania Journal of Science
Lignin is the complex polymer and very few microorganisms are able to degrade it. The study aimed at isolating lignin degrading fungi from soil contaminated with cow dung using ligninolytic screening media. The study was able to isolate one ligninolytic fungus by using lignin media. The strain was screened for production of ligninolytic enzymes using Rhemazol Brilliant blue R (RBBR) dye, 2,2-azino-bis (3- ethylbenzthiazoline)-6-sulfonate (ABTS) and guaiacol in a semi-solid medium. The isolate decolourized RBBR dye, ABTS and guaiacol in a semi solid media. The strain was further tested for lignin peroxidase (LiP), manganese peroxidase (MnP) and laccase (Lac) enzymatic …
Assessment Of Concentrations Of Trace And Toxic Heavy Metals In Soil And Vegetables Grown In The Vicinity Of Manyoni Uranium Depositin Tanzania, F.A. Kapile, In Makundi
Assessment Of Concentrations Of Trace And Toxic Heavy Metals In Soil And Vegetables Grown In The Vicinity Of Manyoni Uranium Depositin Tanzania, F.A. Kapile, In Makundi
Tanzania Journal of Science
This study reports on determination of concentrations of trace and toxic heavy metals in soil and vegetables grown near of Manyoni uranium deposit. Soil and vegetable samples were collected from five sites namely Mitoo Mbuga, farming area, Miyomboni, Tambukareli and near water pump. The concentrations of heavy metals in soil and edible vegetables samples were analyzed using Energy Dispersive X-ray Fluorescence Spectrometry (EDXRF).All vegetable samples were found to have higher concentrations (in μg/g) of trace elements such as Ni (67.3) in pea leaves, Cu (14.9) in pumpkin leaves, Fe (478.6), (200.5) and (337.1) in pea, pumpkin and spinach leaves respectively, …
Establishment Of Background Radiation Dose Rate In The Vicinity Of The Proposed Manyoni Uranium Project, Singida, Joyce Elisadiki, Ismael Makundi
Establishment Of Background Radiation Dose Rate In The Vicinity Of The Proposed Manyoni Uranium Project, Singida, Joyce Elisadiki, Ismael Makundi
Tanzania Journal of Science
The absorbed dose rate in air in the vicinity of the proposed Manyoni uranium mining project located in Singida region, Tanzania, was determined so as to establish the baseline data for background radiation dose rate data prior to commencement of uranium mining activities. Twenty stations in seven villages were selected and monitored for six months from June 2012 to November 2012. The absorbed dose rate in air was measured by means of CaF2:Dythermoluminescent dosimeters (TLD-200). The annual effective dose was estimated using outdoor occupancy factor of 0.2 and conversion coefficient factor of 0.7 SvG y-1. The mean dose rate was …
Removal Of Heavy Metal Ions From Aqueous Solution Using Rice Husks-Based Adsorbents, Fanuel J Ligate, James E.G Mdoe
Removal Of Heavy Metal Ions From Aqueous Solution Using Rice Husks-Based Adsorbents, Fanuel J Ligate, James E.G Mdoe
Tanzania Journal of Science
This study reports on the preparation and characterization of rice husks-based adsorbents and their application in the removal of heavy metal ions from aqueous solution. Three different adsorbents were developed: rice husks ash (RHA), rice husks ash-derived silica (RHS) and triaminopropyl-silica hybrid (TSH-R). The prepared materials were characterized by acid titration, Attenuated Total Reflectance Fourier Transform Infrared (ATR-FTIR) spectroscopy, Scanning Electron Microscopy-Energy Dispersive X-ray (SEM-EDX) spectroscopy and nitrogen physisorption analysis. Results from the ATR-FTIR analysis indicated that pure silica was obtained from RHA and that after surface modification the triaminopropyl group was successfully attached onto the silica framework with a …
Exploring Differences Among Illegal Activities In The Ugalla Game Reserve Of Western Tanzania, Paulo Wilfred
Exploring Differences Among Illegal Activities In The Ugalla Game Reserve Of Western Tanzania, Paulo Wilfred
Tanzania Journal of Science
Conservation efforts in Tanzania rarely assess the extent to which different resource user activities are related. This study aimed to explore the differences among various illegal activities occurring in Ugalla Game Reserve, western Tanzania. The study used a combination of ranger–collected data, from 2003 to 2010, and foot surveys of illegal activity signs in the reserve. Illegal activity signs were recorded for five different types of offence: illegal fishing, bushmeat hunting, illegal logging, other activity (any sign that indicated any other type of unauthorised user presence) and honey gathering. The most frequent activity was logging (602 signs; 58% of offenders …
Comparison Of Accuracies In Techniques For Evaluating Wind Power Density, Reuben Kainkwa, John Kumwenda
Comparison Of Accuracies In Techniques For Evaluating Wind Power Density, Reuben Kainkwa, John Kumwenda
Tanzania Journal of Science
Wind power is among important renewable sources of energy. In order to know the magnitude of wind power, appropriate techniques for evaluating it need to be investigated. Apart from the standard formula that can be used to evaluate wind power density at a site there are two more techniques namely power law exponent and Weibull two-parameter density function. However the accuracy of the latter two methods relative to the standard one has not yet been investigated. The main objective of this paper is to compare accuracies of these techniques. The wind power densities were calculated using standard formula, Weibull model …
Assessment Of Heavy Metal Concentration In Water Around The Proposed Mkuju River Uranium Project In Tanzania, Firmi P. Banzi, Peter K. Msaki, Najat K. Mohammed
Assessment Of Heavy Metal Concentration In Water Around The Proposed Mkuju River Uranium Project In Tanzania, Firmi P. Banzi, Peter K. Msaki, Najat K. Mohammed
Tanzania Journal of Science
Effective verification for compliance with water quality standards in uranium mining in Tanzania requires data sensitive to monitor heavy metal concentration in water around the Mkuju River Uranium Project before mining commences. The area susceptible for pollution by the project was estimated using AERMOD dispersion model and found to cover about 1300 km2. Thirty one surface and groundwater samples were collected and analysed for heavy metals and physicochemical properties using ICP-MS and standards techniques, respectively. The physicochemical properties for water samples analysed ranges from 5.7 to 7.8 for pH, 2.8 to 80.2 mg/L for TDS and 15 to 534.5 mS/cm …
Effects Of Target Composition On The Optical Constants Of Dc Sputtered Zno:Al Thin Films, B. Samwel, M. E. Samiji, N.R. Mlyuka
Effects Of Target Composition On The Optical Constants Of Dc Sputtered Zno:Al Thin Films, B. Samwel, M. E. Samiji, N.R. Mlyuka
Tanzania Journal of Science
Al-doped ZnO thin films were deposited from ZnO:Al ceramic and Zn:Al metal alloy targets in Ar and Ar + O2 atmospheres respectively, using Direct Current (DC) magnetron sputtering. The samples exhibited transmittance T > 80% in visible region with good NIR shielding. The results indicated that, band gap energy ranged from 3.34 to 3.44 eV and 3.39 to 3.46 eV for films prepared from alloy and ceramic targets, respectively. Films obtained from alloy target at a substrate temperature of 200 oC showed low electrical sheet resistance of 10 Ω/sq, and highest values of mobility (15.9 cm2/Vs) and carrier concentration (2.98 × …
Properties Of Multilayered Zno/Al/Zno Transparent Film Electrodes: Models And Experiments, E. R. Rwenyagila, M. E. Samiji
Properties Of Multilayered Zno/Al/Zno Transparent Film Electrodes: Models And Experiments, E. R. Rwenyagila, M. E. Samiji
Tanzania Journal of Science
ZnO/Metal/ZnO multilayers have been recognized as good candidates for transparent conductive thin films for applications in solar cells and optoelectronic devices. One of the important challenges in the experimental designs of such structures is the lack of optimum metal thickness range such as Al in ZnO/Al/ZnO multilayers. The present work overcomes this limitation by investigating how Al thickness affects the optical properties of such multilayered films. In this paper, optical simulations are used to explore the possibility of ultrathin, high transparent ZnO/Al/ZnO multilayer films. Multilayered ZnO/Al/ZnO film with mid-Al layer thicknesses between 1 and 10 nm are shown to have …
Traditional Medicinal Uses Of Small Mammal Products: A Case Study Of The African Savannah Hares, Crested Porcupines And Rock Hyraxes In Serengeti District, Tanzania, Flora John Magige
Traditional Medicinal Uses Of Small Mammal Products: A Case Study Of The African Savannah Hares, Crested Porcupines And Rock Hyraxes In Serengeti District, Tanzania, Flora John Magige
Tanzania Journal of Science
Traditional medicines, both plant and animal products, have been used to cure various diseases since time immemorial especially in rural areas worldwide. Many studies have focused on traditional plant products, but little research has been conducted on animal traditional medicines. This study investigated the use of small mammal products for medicinal purposes in three villages bordering Serengeti National Park in Serengeti District, Tanzania. A total of 71 respondents were interviewed in Kisangura, Nyamburi and Machochwe villages in November 2010, using questionnaires. Villagers hunted small mammals mainly by dogs for cultural and ornamental reasons. Products of African savannah hare (Lepus microtis), …
Spatio-Temporal Analysis Of Wetland Change In Port Harcourt Metropolis, Olatunde Sunday Eludoyin, Olalekan Akinola
Spatio-Temporal Analysis Of Wetland Change In Port Harcourt Metropolis, Olatunde Sunday Eludoyin, Olalekan Akinola
Tanzania Journal of Science
The study assessed changes of wetland in Port Harcourt Metropolis using geo-information techniques between 1984 and 2015. Landsat images of 1984, 2000 and 2015 of 30m x 30m resolution were used. Supervised classification was used for image classification using Maximum Likelihood Algorithm in Erdas Imagine 9.1 whereby five major landuse classes were identified namely thick vegetation, built up area, farmland/sparse vegetation, wetlands and waterbodies. Areas in squared kilometers of each landuse were calculated in ArcGIS 9.3 and simple arithmetic was used to compute the percentage change. Probability of landuse change in the next 10, 20 and 30 years was determined …
Luminous Transmittance And Phase Transition Temperature Of Vo2:Ce Thin Films Prepared By Dc Reactive Magnetron Sputtering, S Ambonisye, M E Samiji, N R Mlyuka
Luminous Transmittance And Phase Transition Temperature Of Vo2:Ce Thin Films Prepared By Dc Reactive Magnetron Sputtering, S Ambonisye, M E Samiji, N R Mlyuka
Tanzania Journal of Science
Vanadium dioxide (VO2) and cerium-doped vanadium dioxide (VO2:Ce) thin films were prepared by DC reactive magnetron sputtering from vanadium metallic target and V-Ce alloy targets. Luminous transmittance and phase transition temperatures of the films were studied. The Shimadzu SOLIDSPEC-3700 DUV-VIS-NIR spectrophotometer was used to measure the transmittance and reflectance of the films. The phase transition temperature (τc) of the films was obtained from both the transmittance and sheet resistance against temperature curves. A change in sheet resistance of 2 to 3 orders of magnitude was observed for both undoped and Ce-doped VO2 films. Comparison between undoped and doped VO2 films …
Agro-Waste As Source Of Fine And Industrial Chemicals: Synthesis Of 2-Formyl-6-Hydroxybenzoic Acid And 4-Methoxyisobenzofuran-1,3-Dione From Cashew Nut Shell Liquid, Lydia Kisula, Stephen J.M. Mdachi, Charles De Koning, Quintino A. Mgani
Agro-Waste As Source Of Fine And Industrial Chemicals: Synthesis Of 2-Formyl-6-Hydroxybenzoic Acid And 4-Methoxyisobenzofuran-1,3-Dione From Cashew Nut Shell Liquid, Lydia Kisula, Stephen J.M. Mdachi, Charles De Koning, Quintino A. Mgani
Tanzania Journal of Science
This paper reports on the synthesis of 2-formyl-6-hydroxybenzoic acid (8) and 4-methoxyisobenzofuran-1,3-dione (10) from a renewable natural material Cashew Nut Shell Liquid (CNSL) achieved in five and seven steps, respectively. Anacardic acid was isolated from CNSL, dimethoxylated into (E)-methyl 2-methoxy-6-(pentadec-8-enyl)benzoate which was subsequently hydrogenated into methyl 2-methoxy-6-pentadecylbenzoate. Benzylic bromination of the methoxyester, and dehydrobromination afforded (E)-methyl 2-methoxy-6-(pentadec-1-enyl)benzoate which upon ozonolysis gave methyl 2-formyl-6-methoxybenzoate. Oxidation and dehydration of 8 formed methoxyphthalic anhydride (10). The work reported in this paper has further demonstrated the resourcefulness of cashew nut shell liquid as a renewable natural resource for synthesis of fine and industrial chemicals.
Determination Of Radioactivity In Maize And Mung Beans Grown In The Neighborhood Of Minjingu Phosphate Mine, Tanzania, Leonid L. Nkuba, Najat K. Mohammed
Determination Of Radioactivity In Maize And Mung Beans Grown In The Neighborhood Of Minjingu Phosphate Mine, Tanzania, Leonid L. Nkuba, Najat K. Mohammed
Tanzania Journal of Science
Two staple foods (maize and mung beans) which were cultivated in Minjingu village, where there are phosphate deposits in Tanzania, were collected directly from the farms. The activity concentrations of 226Ra, 228Th and 40K were determined in the maize and mung beans samples using γ-ray spectrometry employing HPGe detector of relative efficiency of 51.0%. The mean radioactivity levels in the food samples were found to be 21.01 ± 0.8 Bq/kg (mung beans), 25.6 ± 0.7 Bq/kg (maize) for 226Ra, 62.6 ± 1.1 Bq/kg (mung beans), 72.9 ± 1.0 Bq/kg (maize) for 228Th and 542.9 ± 8.6 Bq/kg (mung beans), 434.6 …
Determination Of Radon Gas And Respirable Ore Dust Concentrations In The Underground Merelani Tanzanite Mines, Evarist M. Kahuluda, Ismael N. Makundi
Determination Of Radon Gas And Respirable Ore Dust Concentrations In The Underground Merelani Tanzanite Mines, Evarist M. Kahuluda, Ismael N. Makundi
Tanzania Journal of Science
This study has estimated the concentrations of radon gas and respirable ore dust in the Merelani underground tanzanite mines. Two different portable monitors were used to measure the radon gas and respirable ore dust concentrations, respectively. The mean radon gas concentrations (disintegrations per second per cubic meter) ranged from 40.1 Bq/m3 to 4.2 x 103 Bq/m3 with the geometric mean of 118.4 Bq/m3 which is below the ICRP workplace guidance level of 500 - 1500 Bq/m3. The estimated mean annual effective dose (D) was 1.6 mSv which is significantly lower than the external exposure annual effective dose of 20 mSv …
The Impacts Of Anthropogenic Activities On The Vegetation Communities And Structure In The Western Part Of Rungwe Forest Reserve, Tanzania, Joseph Mwakosya, Cosmas Mligo
The Impacts Of Anthropogenic Activities On The Vegetation Communities And Structure In The Western Part Of Rungwe Forest Reserve, Tanzania, Joseph Mwakosya, Cosmas Mligo
Tanzania Journal of Science
Rungwe Forest Reserve is among the degraded southern Tanzania tropical montane forests. It was investigated the effects of illegal anthropogenic activities on the plant community structure on the western part of Rungwe mountain forest reserve. The study area was classified into three levels of disturbance (least disturbed, moderately disturbed and highly disturbed) and transect method was used to collect data. Two clusters (clusters A and B) of plant communities based on Two Way Indicator Species Analysis (TWINSPAN) were found. Cluster A included communities from the least and moderate disturbed sites and cluster B had plant communities from the highly disturbed …
Spatial Patterns Of Zooplankton Distribution And Abundance In Relation To Phytoplankton, Fish Catch And Some Water Quality Parameters At Shirati Bay, Lake Victoria-Tanzania, Revania K. Waya, Samwel M. Limbu, Godfrey W. Ngupula, Chacha J. Mwita, Yunus D. Mgaya
Spatial Patterns Of Zooplankton Distribution And Abundance In Relation To Phytoplankton, Fish Catch And Some Water Quality Parameters At Shirati Bay, Lake Victoria-Tanzania, Revania K. Waya, Samwel M. Limbu, Godfrey W. Ngupula, Chacha J. Mwita, Yunus D. Mgaya
Tanzania Journal of Science
Spatial patterns and abundance of zooplankton in aquatic habitats are important determinants for production of fish species, invertebrates and availability of phytoplankton. Weekly monitoring for zooplankton abundance was conducted in Shirati Bay, Lake Victoria, to explore their spatial patterns in relation to phytoplankton, fish catch and some water quality parameters. The vertical distribution of zooplankton was generally higher close to the bottom as compared to surface waters of the lake. Zooplankton vertical distribution positively correlated with water transparency (r = 0.680, p = 0.011). The horizontal abundance of zooplankton was not significantly different amongst the three stations (p = 0.5143). …
Analysis Of Body Shapes Among Barbus Trimaculatus, Barbus Paludinosus And Barbus Jacksonii (Actinopterygii: Cyprinidae) From Malagarasi And Pangani River Basins Based On Geometric Morphometric Method, Chacha J. Mwita, B.G. Kamugisha
Analysis Of Body Shapes Among Barbus Trimaculatus, Barbus Paludinosus And Barbus Jacksonii (Actinopterygii: Cyprinidae) From Malagarasi And Pangani River Basins Based On Geometric Morphometric Method, Chacha J. Mwita, B.G. Kamugisha
Tanzania Journal of Science
This study analyzed variability in body shapes among the small Barbus species of the family Cyprinidae currently occurring in the Malagarasi and Pangani River basins years after uplift of the east African topology. Fish specimens were collected from Songati, Muumbara and Nyamagoma within the Malagarasi River basin; Hale and Pangani fall located on Pangani River. It was found that although the landmarks were placed at the same anatomical regions, significant body shapes variations existed. The relative warps analysis for Barbus trimaculatus and Barbus jacksonii populations from Malagarasi and Pangani wetlands revealed intra-locality variations as for populations from other African countries. …