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Full-Text Articles in Entire DC Network
Exploring Technological Strategies For Valorization Of Solid Sisal Waste: A Research Review, Amelia Kivaisi, Anthony Mshandete
Exploring Technological Strategies For Valorization Of Solid Sisal Waste: A Research Review, Amelia Kivaisi, Anthony Mshandete
Tanzania Journal of Science
The sisal industry in Tanzania generates large amounts of waste which is an un-tapped bioresource. Research was undertaken to establish appropriate technologies for its valorisation to mushrooms, biogas and biogas manure (BGM).Physical and biological pre-treatments achieved methane yield increments of 23-30% whereas co-digestion with fish waste achieved methane yield increments of 59-94%. Sisal fibre waste was demonstrated to be a novel biofilm-carrier for treating sisal pulp leachate. With a loading rate of 9.0 kgVS/m3/day, the packed-bed bioreactor was operated without process stress. Sisal decortication waste (SLDW) and sisal boles (SBW) were found to be suitable for oyster mushroom cultivation. With …
Design Of A Small Scale Wind Generator For Low Wind Speed Areas, Ra Msuya, Rrm Kainkwa, Mi Mgwatu
Design Of A Small Scale Wind Generator For Low Wind Speed Areas, Ra Msuya, Rrm Kainkwa, Mi Mgwatu
Tanzania Journal of Science
Most small scale level wind turbine generators are directly driven system, variable speed, and partially connected power electronic converter system. Choice of such system is to avoid costs associated with gearbox. However, due to low wind speed in most of the tropical countries, synchronous generators with smaller or medium speed Permanent Magnet (PM) generator design found to be important and given high performance efficiency. In order to be able to harvest wind energy in off-grid population efficiently, there was a need to design a synchronous generator that can be able to operate under low wind speed, directly connected to the …
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 …
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, …
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 …
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 …
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 …
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 …
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 …
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.
Formation Of Cell Masses In The Myelencephalon Of The Clawed Frog, Xenopus Muelleri, Flora Stephano
Formation Of Cell Masses In The Myelencephalon Of The Clawed Frog, Xenopus Muelleri, Flora Stephano
Tanzania Journal of Science
An important process in the organization of developing nervous system is the clustering of neurons with similar properties to form nuclei. The development of myelencephalon of Xenopus muelleri, a pipid frog that retains a lateral line system throughout life, was studied in Nissl stained serial sections. The results showed that density of neurons increases as the animal develops. Cell masses were formed in the latter half of larval stages (stage 48 to 59). Large neurons migrate first before small neurons. Raphes and reticular formation nuclei and Mauthner cells were the earliest neurons that could be distinctly recognized on the ventral …
Synthesis And Physico-Chemical Studies Of Azo Dyes From Anacardic Acid, An Inexpensive Renewable Resource, John Mkungu, Quintino Mgani, Stephen Mdachi
Synthesis And Physico-Chemical Studies Of Azo Dyes From Anacardic Acid, An Inexpensive Renewable Resource, John Mkungu, Quintino Mgani, Stephen Mdachi
Tanzania Journal of Science
(3AP) and 4-aminophenol (4AP) with both unsaturated (UA) and saturated (SA) anacardic acidsand the calcium salt (CA) of the unsaturated acid. The six prepared dyes are, thus, given theacronyms 3APSA, 3APUA, 3APCA, 4APSA, 4APUA, and 4APCA depending on the source of thediazonium salt and the form of anacardic acid used. The dyes were characterized using UV-Visand FT-IR spectroscopic techniques. The UV-Vis absorption spectra of the dyes were found tohave maximum peaks at 520 nm for the dyes of 3AP origin and at 295 nm for the dyes of 4APorigin. The FT-IR spectra for the dyes indicated presence of the azo …
Population Dynamics Of Pseudo-Nitzschia Species (Bacillariophyceae) In The Near Shore Waters Of Dar Es Salaam, Tanzania, Charles Lugomela
Population Dynamics Of Pseudo-Nitzschia Species (Bacillariophyceae) In The Near Shore Waters Of Dar Es Salaam, Tanzania, Charles Lugomela
Tanzania Journal of Science
The genus Pseudo-nitzschia is a chain-forming diatom comprising about 30 species some of which are known to produce domoic acid (DA) that causes amnesic shellfish poisoning (ASP). The current study aimed at assessing the population dynamics of Pseudo-nitzschia in the near shore waters of Dar es Salaam. Samples were collected between August 2008 and July 2009 from two stations. The first station was located in the open waters off Mbudya Island and the second was located at a point in-between Kunduchi and Mbudya Island. Three Pseudo-nitzschia species, i.e., Pseudo-nitzschia pungens, Pseudo-nitzschia seriata and Pseudo-nitzschia cuspidata were encountered with Pseudo-nitzschia pungens …
Salt Lakes Of The African Rift System: A Valuable Research Opportunity For Insight Into Nature’S Concenrtated Multi-Electrolyte Science, Jyn Philip, Dms Mosha
Salt Lakes Of The African Rift System: A Valuable Research Opportunity For Insight Into Nature’S Concenrtated Multi-Electrolyte Science, Jyn Philip, Dms Mosha
Tanzania Journal of Science
The Tanzanian rift system salt lakes present significant cultural, ecological, recreational and economical values. Beyond the wealth of minerals, resources of these rift salt lakes include unique wildlife, for instance Lesser Flamingo (Phoenicopterus minor) and Cichlids (Alcolapia spp), which adapted chemically aggressive environments like that of Lake Natron. The general hydrochemical equilibria of these salt lakes is governed by Na+ > K+ >> Ca2+ ~ Mg2+ : (CO32- + HCO3-) > Cl- > SO42-~ F- ionic concentration pattern. Salt accumulation mechanism in these endorheic lakes is considered to base on thermo-mechanical disintegrative stress of the geochemistry sourcing. The rains chemically interact with rift terrains, …
Determination Of Lipophilic Extractives In Ionic Liquid Extracts Of Eucalyptus Pulp By Gas Chromatography - Mass Spectrometry, Kf Kilulyaa, Tam , Msagati, Bb , Mamba, Jc Ngila, T Bush
Determination Of Lipophilic Extractives In Ionic Liquid Extracts Of Eucalyptus Pulp By Gas Chromatography - Mass Spectrometry, Kf Kilulyaa, Tam , Msagati, Bb , Mamba, Jc Ngila, T Bush
Tanzania Journal of Science
Lipophilic wood extractives composition is currently a big concern of pulp and paper industries as well as for the environmentalists due to their negative impacts on the quality of pulp and the environment. Because of the shortcomings of different extraction procedures using volatile organic solvents in capturing residual lipophilic extractives in pulp, this study reports on the use of ionic liquids as an effective approach for such extraction. The capacity of two ionic liquids; 1- butyl-3-methylimidazolium acetate and 1-butyl-3-methylimidazolium chloride to recover wood extractives was compared and it was observed that ionic liquid with chloride anion recovered a higher amount …
Molecularly Imprinted Polymer Technology: A Powerful, Generic, Facile And Cost Effective Alternative For Enantio-Recognition And Separation: A Glance At Advances And Applications, Jyn Philip, Dms Mosha
Molecularly Imprinted Polymer Technology: A Powerful, Generic, Facile And Cost Effective Alternative For Enantio-Recognition And Separation: A Glance At Advances And Applications, Jyn Philip, Dms Mosha
Tanzania Journal of Science
The emerging Molecularly Imprinted Polymer (MIP) technology has yielded proof of concept, harnessing nature’s fundamentals to yield recognition receptor mimics from the miniaturized basics, borrowing on the ground rules, but conveniently avoiding the complexity, fragility, instability, costs and ethics of animal based bio-affinity matrices. Thus, the impact of bio-sciences on the future of technology is not via direct use of the molecules, but rather the lessons learned. Molecular imprinting is a powerful specialty representing the generic, cost effective and facile alternative for preparation of synthetic custom-tailored receptors. It achieves this via creation of specific selective recognition sites for a pre-determined …
Theoretical Study Of Physiochemical Properties Of Insulin-Like Growth Factor 1, A Ilkhani
Theoretical Study Of Physiochemical Properties Of Insulin-Like Growth Factor 1, A Ilkhani
Tanzania Journal of Science
The computational approach to studying structural changes in a wide range of physical and biological problems, the empirical force fields, have great difficulty in simulating folding of Insulin-like Growth Factor 1 (IGF-1). In an effort to understand the conformational preferences that may be attributed to stereoelectronic effects, a number of computational studies were carried out. Monte Carlo, Molecular Dynamics and Langevin simulation methods by MM+, AMBER and OPLS force fields of calculations have been performed on IGF-1 as growth factors. The parameters of a minimized structure of IGF-1, calculated potential energy for important dihedral angles and the effect of temperature …
Probing The Cob(Ii)Alamin Cond Uctorhhypothesis With Glutamate Mutase From Clostridium Cochlearium, Fe Lyatuu, A Parthasarathy, K Zhou, K Zelenka, Fh Zelder, W Buckel
Probing The Cob(Ii)Alamin Cond Uctorhhypothesis With Glutamate Mutase From Clostridium Cochlearium, Fe Lyatuu, A Parthasarathy, K Zhou, K Zelenka, Fh Zelder, W Buckel
Tanzania Journal of Science
It had been proposed that during reversible coenzyme B12 dependent rearrangements, cob(II)alamin is not merely present as a spectator but also acts as a conductor by stabilizing the methylene radical intermediates. Density functional theory (DFT) calculations suggested a hydrogen bond between C19-H of the corrin ring and the 3'-OH moiety (O3RL) of the 5'- deoxyadenosyl radical resulting in a decrease of the activation energy by about 30 kJ mol-1. We tested this hypothesis with glutamate mutase and artificial coenzyme B12 derivatives. The assembly of coenzyme B12 (adenosylcobalamin) with recombinant components GlmS and GlmE of glutamate mutase from Clostridium cochlearium reconstitutes …
Effects Of Temperature On The Physicochemical Properties Of Traditionally Processed Vegetable Oils And Their Blends, Fn Ngassapa, Ss Nyandoroa, Tr Mwaisaka
Effects Of Temperature On The Physicochemical Properties Of Traditionally Processed Vegetable Oils And Their Blends, Fn Ngassapa, Ss Nyandoroa, Tr Mwaisaka
Tanzania Journal of Science
The quality and stability of traditionally processed palm, sunflower and sesame oils and their blends as affected by temperature were evaluated by analyzing their physicochemical properties which included acid, saponification, peroxide, iodine values and refractive indices.. The initial quality of traditionally processed oils studied was found to be within the specifications of TZS and Codex requirements. The results further indicate that the quality of both unblended and blended traditionally processed vegetable oils deteriorate significantly at elevated temperatures (p < 0.05). However, the blends showed relatively better quality and stability than the unblended ones whereby the formulations of palm oil (PO) and sesame oil (SSO) appeared to be more stable than those of PO and sunflower oil (SO). This work suggests that blending of traditionally processed PO, SO and SSO improves the quality and stability of these oils.
Comparison Of Chemical Nano Structure, Rheological And Mechanical Properties Of Long Oil Alkyd Resin Synthesized Using Polybasic Acids Catalyst, Ar Ilkhani
Tanzania Journal of Science
In this research, chemical nano structures, rheological and mechanical properties of long oil alkyd resin which was synthesized using different polybasic acid catalysts have been studied. These catalyst were phosphoric acid, 1,2,4-benzene tricarboxylic acid and succinic acid. The new compounds were compared with reference formula of long oil alkyd resin. For this idea, same formula of clear air drying varnishes were prepared based on different long oil resins which have been synthesized using different catalysts and reference long oil alkyd resin. FTIR spectroscopy was employed to investigate the nano chemical structures of the resins and varnishes. The rheological properties of …
Evaluation Of Patterns And Spatial Trends Of Pesticide Residues From Vikuge Farm, Coast Region, Tanzania By Principal Components Analysis, Kf Kilulya, Gs Mhinzi
Evaluation Of Patterns And Spatial Trends Of Pesticide Residues From Vikuge Farm, Coast Region, Tanzania By Principal Components Analysis, Kf Kilulya, Gs Mhinzi
Tanzania Journal of Science
This paper reports on the analysis of organochlorine pesticides pollution data obtained from samples collected from Vikuge farm, Coast Region, Tanzania between 2000 and 2003 by principal component analysis (PCA). PCA of the data sets for pesticide residues in water, soil and sediments samples from Vikuge has shown that the obsolete pesticides dumped at Vikuge pasture farm for a number of years undergo degradation with time and the distribution pattern of the pesticides in the three environments is similar. Strong outliers were also identified in the data by the use of PCA score plots. Further analysis of the data by …
Biorecognition Ability Of Polysaccharides As Piezo Quartz Biosensors, En Kalmykova, Ca Mgina
Biorecognition Ability Of Polysaccharides As Piezo Quartz Biosensors, En Kalmykova, Ca Mgina
Tanzania Journal of Science
Piezoquartz biosensors (PQB) which are analytical devices for recognition of biochemical interactions have recently attracted increasing interest from different researchers such as analysts, immune-chemists, medical doctors, environmentalists, etc. This is due to the advantages of PQB for having high detection sensitivity (at ng and mg level depending on the mass of sorbates or micro-organisms) and the ability to monitor biochemical reactions in turbid or highly coloured liquids (including in biological fluids) in real time. The use of additional markers and preliminary sample preparation are not required in this biorecognition process. This paper reports on the principle of the PQB and …
Polyphenoloxidase And Perioxidase Activity During Open Air Ripening Storage Of Pineapple (Ananas Comosus L.), Mango (Mangifera Indica) And Papaya (Carica Papaya) Fruits Grown In Dar Es Salaam, Tanzania, Oc Othman
Tanzania Journal of Science
Polyphenoloxidase (PPO) and perioxidase (POD), the enzymes responsible for causing browning and change in texture and flavor of fruits and vegetables, were extracted and measured in harvested mature pineapple (Ananas comosus L.), mango (Mangifera indica) (Viringe and Dodo varieties) and papaya (Carica papaya) fruits during off vine, open air, room temperature ripening storage. The initial (at harvest) average PPO activity values in Δ Optical Density (OD) per minute per cm3 of enzyme solution were 0.00074, 0.00083 and 0.0010 for early, mid and late season pineapple fruits respectively. The initial average PPO activity values in ΔOD/min/ cm3 of enzyme solution were …