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Uvarisesquiterpene D: A New Benzopyranyl Sesquiterpene Isolated From Uvaria Lucida Ssp. Lucida, Qa Mgani Dec 2012

Uvarisesquiterpene D: A New Benzopyranyl Sesquiterpene Isolated From Uvaria Lucida Ssp. Lucida, Qa Mgani

Tanzania Journal of Science

Hitherto unreported benzopyranyl sesquiterpene, uvarisesquiterpene D, has been isolated from the stem bark of Uvaria lucida ssp lucida. Its structure had been elucidated by spectroscopic analysis (IR, MS and NMR) and comparison of its spectral data with the known related compounds uvarisesquiterpene B and selin-11(12)-4α-ol. The latter compound was co-isolated with the new natural product as well as caryophyline oxide and lucidine.


Status Of Pesticides And Degradation Products In Soil After Clean-Up Of Stockpiles And Treatment With Sodium Hydroxide At A Former Storage Site In Korogwe, Tanzania, Jam Mahugija Dec 2012

Status Of Pesticides And Degradation Products In Soil After Clean-Up Of Stockpiles And Treatment With Sodium Hydroxide At A Former Storage Site In Korogwe, Tanzania, Jam Mahugija

Tanzania Journal of Science

The status of pesticide residues in soil samples collected from a former storage site one year after clean-up of stockpiles and treatment with NaOH was investigated. The analytes were extracted from samples by pressurized fluid extraction using n-hexane:acetone (75:25) mixture. Clean-up of extracts was conducted by using silica gel and alumina with 3% H2O and the extracts were eluted with hexane:dichloromethane (1:1). Extra clean-up was performed through C18 SPE cartridges using acetonitrile as the eluting solvent. Labelled internal standards were used for identification and quantification. Analysis of the analytes was performed using a high resolution GC–MS. The dominant contaminants detected …


Computational Chemistry Capacity Building In An Underprivileged Context: Challenges, Outcomes And Perspectives, L Mammino Dec 2012

Computational Chemistry Capacity Building In An Underprivileged Context: Challenges, Outcomes And Perspectives, L Mammino

Tanzania Journal of Science

Computational chemistry is a fast developing branch of modern chemistry, focusing on the study of molecules to enable better understanding of the properties of substances. Its applications comprise a variety of fields, from drug design to the design of compounds with desired properties (e.g., catalysts with specific actions) and to ample overlaps with nanotechnology. However, despite its relevance, the presence of computational chemistry research in Sub-Saharan Africa is still scarce, practically absent in many institutions. Bridging the gap with the other continents requires the identification of capacity building options that may enable a rapid growth. The recent experience at the …


Development Of Information And Communication Technology In Education In Tanzania: How Is Duce Playing Its Role?, Josta L. Nzilano, Ayoub C. Kafyulilo Dec 2012

Development Of Information And Communication Technology In Education In Tanzania: How Is Duce Playing Its Role?, Josta L. Nzilano, Ayoub C. Kafyulilo

Journal of Humanities and Social Sciences

This paper presents the ICT integration situation in Tanzania, and the efforts that are being made by the Dar es Salaam University College of Education (DUCE), as a teacher training institution, to have ICT integrated in the education system at the college and country at large. Over 60 articles and reports were gathered and read in the process of writing the paper. However, through rigorous review of each article only 35 were found to match best with the goal of this study. Results from literature indicate that technology integration in the country was still at an infant stage. Most educational …


The Impact Of Income Generating Programs At Tarangire National Park, Tanzania, Dylan Mcdowell Oct 2012

The Impact Of Income Generating Programs At Tarangire National Park, Tanzania, Dylan Mcdowell

Independent Study Project (ISP) Collection

Tarangire National Park (TAR) is Tanzanian’s third largest grossing park, and is surrounded by 42 villages in five districts. The park’s single Outreach Warden has undertaken many projects since the park’s creation in 1970 to engage the villagers in natural resource conservation, including wildlife. The newest pilot project at TAR is Income Generating Programs (IGP) where community groups organize themselves around an activity that earns income. From September 24-29, 2012, TAR selected 10 members from three groups in the park’s northern end and 15 members from two groups in the park’s southern end to attend an all-expenses paid business class …


Correlation Between Morphological, Optical And Electrical Properties Of Zno:Al/Zno Double Layers And The Cu(In,Ga)Se2 Solar Cell Efficiencies, Pd Nsimama Jul 2012

Correlation Between Morphological, Optical And Electrical Properties Of Zno:Al/Zno Double Layers And The Cu(In,Ga)Se2 Solar Cell Efficiencies, Pd Nsimama

Tanzania Journal of Science

The morphological, optical and electrical properties of magnetron sputtered ZnO:Al/ZnO double layers are reported and their correlations with their respective Cu(In,Ga)Se2 (CIGS) solar cell efficiencies are presented. The ZnO:Al/ZnO double layers were produced by using the established baseline RF process and plasma emission monitoring (PEM) DC reactive sputtering. The scanning electron microscope (SEM) and atomic force microscope (AFM) were employed for the surface morphological measurements. The charge carrier concentrations, mobilities and AC resistivities were deduced from Drude’s model. The DC resistivities were determined from the four-point probe measurements. Transmittance and reflectance measurements were done by using the UV-VIS-NIR Lambda 900 …


Paleoseismic Investigations Along The Bubu Fault, Dodoma-Tanzania, As Macheyeki, D Delvaux, Md Batist, A Mruma Jul 2012

Paleoseismic Investigations Along The Bubu Fault, Dodoma-Tanzania, As Macheyeki, D Delvaux, Md Batist, A Mruma

Tanzania Journal of Science

The central part of Tanzania, Dodoma, was hit by an Mw= 5.5 earthquake in November 4, 2002. It was part of a swarm of moderate earthquakes that affected the area. This paper, reports the first attempt to investigate significant past earthquakes along one of the known seismically active riftfaults (Bubu fault, Gonga segment) by paleoseimological trenching. The trench revealed over 3 episodes of faulting (2 of which correspond to Mid-Holocene faulting). The magnitude of the largest earthquake illustrated in the trench is estimated at Mw = 6.3-6.4 and the slip rate between two recent faulting events is about 0.11 to …


Performance Of Subsurface Flow Constructed Wetland For Domestic Wastewater Treatment, Jp Mairi, Tj Lyimo, Kn Njau Jul 2012

Performance Of Subsurface Flow Constructed Wetland For Domestic Wastewater Treatment, Jp Mairi, Tj Lyimo, Kn Njau

Tanzania Journal of Science

Constructed wetlands (CW) have recently emerged as efficient technology for secondary treatment of wastewater in developing countries because of its low cost, ease operation, maintenance and generally good performance. At present there are a number of small scale units of CW for wastewater treatment in Tanzania but information on their performance is scarce. This study investigated the removal efficiency of fecal bacteria indicators, inorganic nutrients and Biochemical Oxygen Demand (BOD) from wastewater by a CW at the University of Dar es Salaam. The CW received wastewater from a primary facultative pond and was a monoculture system planted with Phragmites mauritianus …


Electrical Properties Of Dc Reactive Magnetron Sputtered Zno:Al Films From Optical Spectra, Pd Nsimama, Me Samiji Jul 2012

Electrical Properties Of Dc Reactive Magnetron Sputtered Zno:Al Films From Optical Spectra, Pd Nsimama, Me Samiji

Tanzania Journal of Science

Reactive direct current (DC) sputtered ZnO:Al films were prepared using the plasma emission monitoring (PEM) system. Films were deposited using PEM setpoints ranging from 50 to 80%. Transmittance and reflectance of the films were measured by using the UV-VIS-NIR Lambda 900 double beam spectrophotometer. The sheet resistance was measured using the four-point probe. Films optical spectra were fitted with the Drude model to determine their charge carrier concentration, mobility and the alternating current (AC) resistivity. The highest values of mobility and charge carrier concentration were 8.31cm2/Vs and 2.14 x 1021cm-3 respectively. The lowest value of the AC resistivity was given …


Wet Oxidation Of Maleic Acid By A Pumice Supported Copper (Ii) Shiff Base Catalyst, Jeg Mdoe, Raj Minja, L Daniel Jul 2012

Wet Oxidation Of Maleic Acid By A Pumice Supported Copper (Ii) Shiff Base Catalyst, Jeg Mdoe, Raj Minja, L Daniel

Tanzania Journal of Science

Pumice supported Cu (II) Schiff base catalysts were prepared by surface chemical modification followed by complexation with Cu (II) acetate. The resulting materials were characterised by Diffuse Reflectance Fourier Transform Spectroscopy (DRIFTS) to confirm the modification. The materials were tested in a wet oxidation of maleic acid using air or hydrogen peroxide as an oxidant. Results indicate that up to 80% degradation of maleic acid could  be achieved in the presence of the catalyst using hydrogen peroxide as an oxidant. The degradation was found to depend on the type of oxidant, temperature and whether the parent pumice was acid pre-treated …


Ni Mineralization And Pge Characterization In The Kabanga And Luhuma Ni-Cu Sulfide Deposits, North West Tanzania, As Macheyeki Jul 2012

Ni Mineralization And Pge Characterization In The Kabanga And Luhuma Ni-Cu Sulfide Deposits, North West Tanzania, As Macheyeki

Tanzania Journal of Science

Nickel mineralization in the Kabanga sulfide ores is found associated with (1) peripheral veins in the country-rock metapelites, (2) contact type massive sulfide mineralization, and (3) disseminated and vein mineralization. This work, apart from giving general highlight of the Ni mineralization (and other associated elements) in the Kabanga and Luhuma, intends to assess the PGE content in both areas. Cores (mafic-ultramafic and metasedimentary rocks as well as ore sections) from both Kabanga and Luhuma areas were sampled, cut, crushed, pulverized and analyzed for both major and trace elements. Results show that all the Iridium Platimum Group Elements (IPGEs) have very …


Simplified Models Of Vector Control Impact Upon Malaria Transmission By Zoophagic Mosquitoes, Samson S. Kiware, Nakul Chitnis, Sarah J. Moore, Gregor J. Devine, Silas Majambere, Stephen Merrill, Gerry F. Killeen May 2012

Simplified Models Of Vector Control Impact Upon Malaria Transmission By Zoophagic Mosquitoes, Samson S. Kiware, Nakul Chitnis, Sarah J. Moore, Gregor J. Devine, Silas Majambere, Stephen Merrill, Gerry F. Killeen

Mathematics, Statistics and Computer Science Faculty Research and Publications

Background

High coverage of personal protection measures that kill mosquitoes dramatically reduce malaria transmission where vector populations depend upon human blood. However, most primary malaria vectors outside of sub-Saharan Africa can be classified as “very zoophagic,” meaning they feed occasionally (

Methods and Findings

We extended a published malaria transmission model to examine the relationship between transmission, control, and the baseline proportion of bloodmeals obtained from humans (human blood index). The lower limit of the human blood index enables derivation of simplified models for zoophagic vectors that (1) Rely on only three field-measurable parameters. (2) Predict immediate and delayed (with …


How Does Climate Change Affect Agricultural Stability In Southeast Unguja? An Assessment Of The Threats To Agriculture And Food Security From Rising Temperature And Changes In Predictability And Intensity Of Rainy Seasons., Eloise Reid Apr 2012

How Does Climate Change Affect Agricultural Stability In Southeast Unguja? An Assessment Of The Threats To Agriculture And Food Security From Rising Temperature And Changes In Predictability And Intensity Of Rainy Seasons., Eloise Reid

Independent Study Project (ISP) Collection

The relationship between climate change, agriculture, and food security on the island of Unguja was studied. Informal interviews were carried out in the south-eastern coastal communities of Bwejuu, Paje, and Jambiani in order to gain perspective and awareness of local knowledge concerning changes in climate and it's affects on crop production. Formal interviews were conducted in Stone Town with the Ministry of Agriculture, the Department of Environment, the Sustainable Management of Land and the Environment office, private climate change experts and environmental consultants, and local NGO's to gain insight on what aspects of climate change are most detrimental in the …


Assessing The Viability Of Desalination For Rural Water Supply In Chwaka, Zanzibar, Roy Yu, Daniele Packard Apr 2012

Assessing The Viability Of Desalination For Rural Water Supply In Chwaka, Zanzibar, Roy Yu, Daniele Packard

Independent Study Project (ISP) Collection

Zanzibar has been struggling with water scarcity issues over the last few decades due to an increase in consumption on the island and a deterioration of existing supply infrastructure. Poor distribution has affected rural communities most, due to their absence of tourism development, which has gone hand in hand with infrastructure establishment. Foreign aid has begun to address the issue by investing in alternative forms of water supply. On November 15, 2011, The Minister for Housing, Lands, and Water, Ali Juma Shamhuna inaugurated the Mörk desalin® RO 100 SW desalination machine, a solar and wind powered desalination unit in Chwaka …


Synthesis Of Organoamine-Silica Hybrids Using Cashew Nut Shell Liquid Components As Templates For The Catalysis Of A Model Henry Reaction, Sc Msigala, Jeg Mdoe Mar 2012

Synthesis Of Organoamine-Silica Hybrids Using Cashew Nut Shell Liquid Components As Templates For The Catalysis Of A Model Henry Reaction, Sc Msigala, Jeg Mdoe

Tanzania Journal of Science

Organoamine-silica hybrids were prepared by a co-condensation of tetraethoxysilane (TEOS) and different aminoalkoxysilanes, namely, 3-aminopropyltrimethoxysilane, N-(3(trimethoxysilyl)propyl)-ethylenediamine and 3[2(2-amino)ethylamino]propyl trimethoxysilane, at different ratios using cashew nut shell liquid (CNSL) components as templates. Of the major components of CNSL tested, only cardanol was found to be efficient as a template as it yielded 66% of the hybrid. The prepared materials were characterized by diffuse reflectance Fourier Transform Infrared (FTIR), Atomic Force Microscopy and acid titration. Results indicated that indeed the organoamine groups were attached onto the silica surface, with a maximum loading of 2.9 mmol organic group per g silica. The materials …


Environmental Status At Samunge Village (Tanzania) Following A Sharp Increase In Visitors, R Senzota Mar 2012

Environmental Status At Samunge Village (Tanzania) Following A Sharp Increase In Visitors, R Senzota

Tanzania Journal of Science

Starting early 2011, people from all over Tanzania, Africa and overseas flocked Samunge Village in northern Tanzania, to drink a cup of Carissa spinarum concoction claimed to treat diseases hitherto known to be incurable by conventional medicine including HIV-AIDS, hypertension and diabetes. The big number of visitors resulted into vivid environmental impacts including trampling on plants and animals, unplanned discarding of drink and food containers, haphazard sanitation undertakings and overall change in panorama. The present study made some quantification on environmental status in the village during the peak visitor days in March 2011. There was widespread trampling and denudation of …


Mg-Rich Metabasalts From The Southern Musoma –Mara Greenstone Belt: Possible Evidence For Mantle Plume Activity In The Tanzania Craton?, S Manya Mar 2012

Mg-Rich Metabasalts From The Southern Musoma –Mara Greenstone Belt: Possible Evidence For Mantle Plume Activity In The Tanzania Craton?, S Manya

Tanzania Journal of Science

Mg-rich metabasalts from the Simba Sirori to Majimoto segment of the southern Musoma-Mara greenstone belt are the most magnesian lavas reported in the Archaean Tanzania Craton. The lavas yielded a Sm-Nd isochron age of 2768 ± 38 Ma (MSWD = 1.2) and corresponding !Nd(2.7 Ga) values in the range of + 0.66 to + 2.81. The lavas exhibit high MgO contents of up to 16 wt %, Cr (140 – 1590 ppm), Ni (80 – 510 ppm), values which are higher than those of primitive NMORB, but are comparable with those of Archaean komatiitic basalts and modern oceanic plateau basalts. …


Improving Propagation Success Of Dalbegia Melanoxylon (African Blackwood) In Tanzania (I): Characterization Of Mycorrhizal Associated With D. Melanoxylon (African Blackwood) In Tanzania, Wba Washa, Ams Nyomora, Hvm Lyaruu Mar 2012

Improving Propagation Success Of Dalbegia Melanoxylon (African Blackwood) In Tanzania (I): Characterization Of Mycorrhizal Associated With D. Melanoxylon (African Blackwood) In Tanzania, Wba Washa, Ams Nyomora, Hvm Lyaruu

Tanzania Journal of Science

Dalbergia melanoxylon is a plant with valuable wood in the world and therefore is over harvested for timber while its regeneration is very low. The propagation efforts by techniques such as tissue culture or mycorrhiza have not been investigated which instigated conduction of this study. Soil and cuttings were collected from Kilwa, Kilosa and Babati for rooting test, potting media and soil characterization. The results showed that fresh soil improved rooting characteristics while sterilized soil did not due to the presence of mycorrhiza in fresh soil compared to none in sterilized media. The overall rooting in fresh soil in non-mist …


The Influence Of Aliphatic Side Chain Of Anacardic Acid On Molecular Recognition Properties Of Imprinted Polymers, Jyn Philip, J Buchweishaija, Ll Mkayula, L Ye Mar 2012

The Influence Of Aliphatic Side Chain Of Anacardic Acid On Molecular Recognition Properties Of Imprinted Polymers, Jyn Philip, J Buchweishaija, Ll Mkayula, L Ye

Tanzania Journal of Science

The objective of this work was to determine the influence of the aliphatic side chain of anacardic acid on molecular recognition properties of imprinted polymers made from anacardanyl methacrylate (AnMcr). Salicylic methacrylate (SaMcr), a structural analog of AnMcr, was synthesized and used as a functional monomer to prepare imprinted polymers for comparison with AnMcr-based polymers. Using divinylbenzene (DVB) as a cross linker and racemic propranolol as a model template, irregular monolithic particles of poly(SaMcr-co-DVB)m were synthesized in toluene, and spherical beads of poly(SaMcr-co-DVB)b and poly(AnMcr-co-DVB)b weresynthesized in acetonitrile by precipitation polymerization. Although imprinted irregular monolithic particles, poly(SaMcr-co-DVB)m, tested in toluene …


Spectral Analysis Of Ground Magnetic Data In Magadi Area, Southern Kenya Rift, Jg Githiri, Jp Patel, Jo Barongo, Pk Karanja Mar 2012

Spectral Analysis Of Ground Magnetic Data In Magadi Area, Southern Kenya Rift, Jg Githiri, Jp Patel, Jo Barongo, Pk Karanja

Tanzania Journal of Science

The area surrounding Lake Magadi in the southern Kenya rift is characterized by hot springs that issue from fractures distributed along the shores of the lake. Presence of earthquake swarms that cluster in northern margin of Lake Magadi strongly indicate magmatic activity in the area. This study was done as a follow-up to investigate depth to the heat source possibly causing high seismic activity and high heat flow in the area. A ground magnetic survey was conducted to investigate geothermal potential of the area and a magnetic anomaly contour map prepared. Spectral analysis involving determining power spectrum was applied to …


A Perspective On Sea Level Rise And Coastal Storm Surge From Southern And Eastern Africa: A Case Study Near Durban, South Africa, Andrew A. Mather, Derek D. Stretch Mar 2012

A Perspective On Sea Level Rise And Coastal Storm Surge From Southern And Eastern Africa: A Case Study Near Durban, South Africa, Andrew A. Mather, Derek D. Stretch

East Africa

Recent coastal storms in southern Africa have highlighted the need for more proactive management of the coastline. Within the southern and eastern African region the availability of coastal information is poor. The greatest gap in information is the likely effects of a combination of severe sea storms and future sea level rise (SLR) on the shoreline. This lack of information creates a barrier to informed decision making. This research outlines a practical localized approach to this problem, which can be applied as a first order assessment within the region. In so doing it provides a cost effective and simple decision …


Effect Of Temperature And Relative Humidity On The Development And Fecundity Of Chilo Partellus (Swinhoe) (Lepidoptera: Crambidae), A. Tamiru, E. Getu, B. Jembere, T. Bruce Feb 2012

Effect Of Temperature And Relative Humidity On The Development And Fecundity Of Chilo Partellus (Swinhoe) (Lepidoptera: Crambidae), A. Tamiru, E. Getu, B. Jembere, T. Bruce

All Peer-Reviewed Publications

The spotted stemborer, Chilo partellus (Swinhoe) (Lepidoptera: Crambidae), is one of the most important insect pests attacking maize and sorghum in Ethiopia. Recent studies have indicated that the pest is spreading to new locations where it was not reported before. In the current study, laboratory investigations were carried out to determine the combined effect of different levels of relative humidity and temperature regimes on the development and fecundity of C. partellus, as these physical factors are known to play an important role in the life cycle of insects and adaptability to local climate. Developmental time, longevity, potential fecundity and realized …


Calling For Justice In The Goldfields Of Tanzania, Madoshi H. Makene, Jody Emel, James T. Murphy Jan 2012

Calling For Justice In The Goldfields Of Tanzania, Madoshi H. Makene, Jody Emel, James T. Murphy

Geography

Tanzania is the third largest gold exporter in Africa, thanks in part to the liberalization of the mining sector which started in the early 1990s. Neoliberal mining reforms promised a win-win situation in which government, investors and local host communities would benefit through export earnings, profits, local employment, andcorporate social responsibility initiatives (e.g., the building of schools and clinics). While the rising price of gold and foreign investments in mining activities have delivered on some of these promises, many residents in mining regions have not benefited socioeconomically. Worse still, their communities have unjustly borne the brunt of the environmental, social, …


Landsat Remote Sensing Data As An Alternative Approach For Geological Mapping In Tanzania: A Case Study In The Rungwe Volcanic Province, South-Western Tanzania, E. E. Mshiu Dec 2011

Landsat Remote Sensing Data As An Alternative Approach For Geological Mapping In Tanzania: A Case Study In The Rungwe Volcanic Province, South-Western Tanzania, E. E. Mshiu

Tanzania Journal of Science

Rungwe Volcanic Province (RVP) is mostly covered by extrusive rocks that overlain the Precambrian basement. The use of Landsat data in this area has revealed the need of effective use of these data in geological mapping programs in Tanzania. Landsat band ratios 5/1, 3/7, 5/7 and 5/4 as well as R: G: B composite images 7:4:1, 7:5:4, 1/3:5/7:3/5 and 4/5:6/7:4/6 played an important role in identifying different rock types in the study area. Ratio images managed clearly to distinguish between mafic and felsic rocks whereby two lithological blocks were identified, Block 1 covers a combination of intrusive and metamorphic rocks …


Variability In Parasites’ Community Structure And Composition In Cat Fish With Respect To Level Of Pollution In Mwanza Gulf, Lake Victoria, Tanzania, C. J. Mwita Dec 2011

Variability In Parasites’ Community Structure And Composition In Cat Fish With Respect To Level Of Pollution In Mwanza Gulf, Lake Victoria, Tanzania, C. J. Mwita

Tanzania Journal of Science

This study investigated the composition and structure of the parasite communities in Cat fish with respect to levels of water pollution in Lake Victoria. A total of 1071 Clarias gariepinus with mean TL range of 19 to 27 cm were analyzed from three localities in Mwanza Gulf (Kirumba, 298 fish infected with 15 parasite species), Nyegezi (376 fish, with 15 parasites species) and Malimbe (397 fish, with 16 parasites species). Trematodes and nematodes dominated the population with six (35.3%) and five (29.4%) species, respectively. Mean species richness and heteroxenous/monoxenous ratio showed significant changes (Fr = 8.000; p = 0.0046), being …


Two Phase Heuristic Algorithm For The University Course Timetabling Problem: The Case Of University Of Dar Es Salaam, A. R. Mushi, A. R. Mushi Dec 2011

Two Phase Heuristic Algorithm For The University Course Timetabling Problem: The Case Of University Of Dar Es Salaam, A. R. Mushi, A. R. Mushi

Tanzania Journal of Science

University course timetabling is the problem of scheduling resources such as lecturers, courses, and rooms to a number of timeslots over a planning horizon, normally a week, while satisfying a number of problem-specific constraints. Since timetabling problems differ from one institution to another, this paper investigated the case of the University of Dar Es salaam, based on the combination of Simulated Annealing (SA), and steepest descent in a two-phase approach. Solutions have been generated which greatly outperform the manually generated ones. Furthermore, the method compares well with previous work on Tabu Search but with faster execution time and higher quality …


Petrography And Geochemistry Of Mafic Granulites Of The Ubendian Belt: Contribution To Insights Into The Lower Continental Crust Of The Paleoproterozoic, N. Boniface Dec 2011

Petrography And Geochemistry Of Mafic Granulites Of The Ubendian Belt: Contribution To Insights Into The Lower Continental Crust Of The Paleoproterozoic, N. Boniface

Tanzania Journal of Science

Mafic granulites of the Ubendian Belt have geochemical signature, trace and REE patterns, similar to that of the lower continental crustal rocks. A SHRIMP U-Pb single zircon date at 1977±40 Ma indicates that these rocks belong to the Paleoproterozoic Ubendian orogenic cycle, which was followed by the Mesoproterozoic tectonic disturbance that contributed to their exhumation. Orthopyroxene, clinopyroxene, garnet, hornblende, plagioclase and quartz is a frequent mineral assemblage for the mafic granulites of the Ubendian Belt, and garnet frequently form corona between plagioclase and clinopyroxene. Geothermobarometric calculations have revealed the equilibration of these rocks at a temperature range between 650 and …


Contact Metamorphism In The Supracrustal Rocks Of The Sukumaland Greenstone Belt In The North West Tanzania, N. Boniface Dec 2011

Contact Metamorphism In The Supracrustal Rocks Of The Sukumaland Greenstone Belt In The North West Tanzania, N. Boniface

Tanzania Journal of Science

Biotite-granite intrusions in meta-ironstones at Geita Hills and the Bukoli alkali-granite intrusion in metabasites at Mawemeru area produced heat that baked the respective country rocks through epidote-amphibolite- to amphibolite-facies. Critical and informative mineral assemblages in the metairostones of Geita Hills are garnet-grunerite-epidote-quartz and garnetferrogedrite- biotite-quartz and in the metabasites of Mawemeru is ferrotschermakite-(Naplagioclase)- quartz. Peak temperatures ranging between 438°C and 544°C were calculated from the above mineral assemblages and a pressure not exceeding 3 kbar was inferred to from the composition of magnesium-iron amphiboles (grunerite with XFe ratio of 0.83, i.e. Gru83). Hornfels textures in the metaironstones are suggested by …


Identification Of Clay Minerals Of The Eastern Southern Region Of Lake Victoria By Ethylene Glycol And Heat: X-Ray Diffraction And Infrared Spectroscopy Studies, E. H. J. Lugwisha Dec 2011

Identification Of Clay Minerals Of The Eastern Southern Region Of Lake Victoria By Ethylene Glycol And Heat: X-Ray Diffraction And Infrared Spectroscopy Studies, E. H. J. Lugwisha

Tanzania Journal of Science

The effect of glycol and heat on some clay minerals of the eastern southern region of Lake Victoria in Tanzania has been studied. First, Whole Rock Powder mount XRD analysis was carried out at the measuring range 2 # ranging between 2o – 65o. Four non-clay minerals found in samples were Na-feldspar, K-feldspar, pyrope and quartz. Oriented clay mineral XRD analysis diffractograms were developed when the air-dried samples were diffracted in measuring range 2# between 2oo – 32o. Main clay mineral groups found in the samples were kaolinite, illite and montmorillonite. After glycolating the samples, it was evident that kaolinite …


Host-Parasites Relationship For Lake Victoria Clariid Fishes And Their Parasite Fauna, C. J. Mwita Dec 2011

Host-Parasites Relationship For Lake Victoria Clariid Fishes And Their Parasite Fauna, C. J. Mwita

Tanzania Journal of Science

Host-parasite co-evolutionary relationships for the clariid fish species of the Lake Victoria basin and their parasite fauna was inferred by cytochrome b gene and the 18S rDNA using ‘a strict coevolutionary’ constrained tree method, the results of which revealed a phylogenetic incongruence between the fish hosts and their parasite fauna. The present study further indicated that the sympatric association between the clariid hosts and non-clariid fishes in Lake Victoria makes it possible for the parasites to switch from one host to another and hence the large number of shared parasites observed. The specificity of some of the parasites, e.g. Diplostomum …