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An Integrated Model For Technology Assessment And Choice For Rural Development In Developing Countries, Abdallah Chungu

Tanzania Journal of Engineering and Technology (TJET)

Abstract

Evaluation Of Pollution Loading Into Msimbazi River By Rapid Assessment And Direct Measurement Methods, J. H. Y. Katima

Tanzania Journal of Engineering and Technology (TJET)

This paper assesses the suitability of Rapid Assessment (RA) methodology as a tool for making an environmental pollution inventory in data poor situation. The RA method was applied to estimate Biological Oxygen Demand (BOD), nitrogen and phosphorous loading into the Msimbazi River in Dar es salaam, Tanzania. The Direct Measurement (DM) was done to validate the results obtained from RA. The methodology is based on estimating waste loads from function variables such as production rate, population, etc. and pollution intensities from domestic, industry and agricultural sources. The incorporation of penetration factors for waste loads reduction refines the assessment procedure. The …

Prediction Of The Response Of Rectangular Cladding Panels To Wind Loading In The Time Domain, Ambrose Shirima

Tanzania Journal of Engineering and Technology (TJET)

The analysis and subsequent design of cladding panels is traditionally based on quasi-static calculation of the wind loads. Pressure coefficients, which are derived from wind tunnel measurements and a design wind speed, are used to compute the wind loading. The codes of practice give the pressure coefficients and the guidelines of deriving the design wind speed from factors, which are specific to the site namely basic wind speed, topography, ground roughness and height above the ground. The concept of design wind speed is simple but it overlooks the resonant vibrations caused by the wind. The paper discusses a procedure for …

Surface Titration Of Colloidal Alpha-Alumina, J. W. Ntalikwa

Tanzania Journal of Engineering and Technology (TJET)

The surface charge density (σ₀) of colloidal alumina (α-Al₂O₃) suspended in 1:1 electrolytes (NaCl, NaNO₃, CsCl and CsNO₃) at different electrolyte concentration (c₀) was determined using acid-base titration. The data were described in terms of the Triple Layer Model (TLM) of electric double layer. It was observed that the polarity of σ₀ could be varied through a point of zero charge (PZC) by varying the pH of the suspension. The PZCs were observed to occur at pH = 7.8 ± 0.1, 7.6 ± 0.2, 8.5 ± 0.1 and 8.3 ± 0.1 in NaCl, NaNO₃, CsCl and CsNO₃, respectively. It was …

A System Thinking Approaching Maintenance, Production And Quality, E. A. M. Mjema

Tanzania Journal of Engineering and Technology (TJET)

The concepts of system thinking and its applicability in maintenance management was analysed in this article. The author analysed various maintenance policies, which have inclination to the concept of system thinking. The maintenance policies revisited include the Integration of Maintenance (IM), Total Quality Maintenance (TQMain), Failure Mode and Effect Analysis (FMEA), and Total Productive Maintenance (TPM). All these strategies are aimed at utilising effectively the maintenance personnel by giving some of the responsibilities of maintenance to production personnel. It was found that, although the founder of these techniques did not mention the concepts of system thinking in their methods, however, …

Centrifugal Extraction Of Avocado Oil From The Pulp, J. W. Ntalikwa

Tanzania Journal of Engineering and Technology (TJET)

Absract

Load Flow Solution For Three-Phase Mv Radial Distribution Connected Network Supplying Different Line Topologies, B. J. Kundy

Tanzania Journal of Engineering and Technology (TJET)

In this paper, a load flow solution for the Medium Voltage (MV) three-phase radial distribution in delta-delta (Δ–Δ) connected network supplying different line topologies such as three phase, phase to phase and single-wire earth return (SWER) networks is presented. The general voltage related network equations are developed using Kirchhoff’s voltage and current laws. Development of a solution to the load flow analysis applying the developed general voltage related network equations is proposed in order to evaluate the network voltage profile. Various numbers of arrays are developed for the identification of the network under study. The proposed method is a new …

The Inclusion Behaviothe Inclusion Behavior Of Sodium Compounds In Sub-Micron Particles Formed During Coal Combustionr Of Sodium Compounds In Sub-Micron Particles Formed During Coal Combustion, Iddi Mkilaha

Tanzania Journal of Engineering and Technology (TJET)

During combustion of coal, biomass and sewage sludge, metallic compounds especially alkali metals such as sodium and potassium vaporize and form fumes which are emitted with the exhaust gases. These fumes are corrosive to the turbine blades of power plants. To minimize corrosion, efforts have been made to control the condensation phase of these metals. In this study, the evolution and inclusion of sodium in sub-micron particles was investigated using a drop tube furnace and a low-pressure impactor (LPI). Four types of coal with different chemical properties were tested. The results suggest that a reaction-controlled mechanism and nucleation via chemical …

Simulation Of The Communication Process In A Pin Mill, Ambrose J. M. Itika

Tanzania Journal of Engineering and Technology (TJET)

Prediction of the performance of comminution equipment by mathematical models and simulation poses a great challenge to the chemical engineer. This paper describes the simulation of grinding results obtained using an impact mill. Single particle results have been used to generate breakage and selection coefficients that were used for the evaluation of the model. Results have shown that simulation model is in good agreement with the experimental data obtained at a circumferential speed above 60 m/s. At lower speeds, the models shows only partial agreement in the middle particle size ranges. The application of the model is therefore limited for …

Using Pedotransfer Functions To Predict Saturated Hydraulic Conductivity For Layered Soil Profiles A Case Study At The Sokoine University Of Agriculture Farm, Tanzania, M. K. Mulengera

Tanzania Journal of Engineering and Technology (TJET)

Saturated soil hydraulic conductivity (SHC), is useful for land resources management. But it is difficult, time consuming, and labour intensive to measure in the field. These problems can be overcome through the use of pedotransfer functions (PTFs), which relate the SHC to readily available soil physical, chemical, and biological parameters. The existing PTFs were developed in temperate countries using homogeneous core soil samples. Thus, these PTFs are not useful for tropical soils with different properties and for layered soil profiles. In this paper, field measured SHC values are related to representative profile soil properties (RSPSPs) that are determined using horizons’ …

Insect Infestation Of Maize, Zea Mays (L.) In Indigenous Storage Structures In Morogoro Region, Tanzania, Cp Rugumamu

Tanzania Journal of Science

Insect infestations and losses of maize stored in four types of indigenous storage structures in Morogoro Region, Tanzania were investigated. Infestation levels and weight losses caused by the larger grain borer, Prostephanus truncatus (Horn) and the maize weevil, Sitophilus zeamais (Motsch.) were found to differ significantly in the four types of storage structures (Dari, Kihenge, Kichanja and Reli). Lower infestation levels by the two pests and less weight losses were observed inDari and Kihenge than in Kichanja and Reli. The infestations and weight losses exhibited a significant trend that was in the order, Dari< Kihenge < Kichanja < Reli. These findings suggest that Dari and Kihenge are more appropriate for the incorporation in Integrated Pest Management (IPM) for P. truncatus and S. zeamais in Morogoro Region.

Performance Of Pleurotus Flabellatus On Water Hyacinth (Eichhornia Crassipes) Shoots At Two Different Temperature And Relative Humidity Regimes, Ak Kivaisi, Fss Magingo, B Mamiro

Tanzania Journal of Science

Efforts are being made in Tanzania to promote mushroom cultivation, and identification of abundantly available plant biomass residues appropriate for growing mushrooms is part of the efforts. This study investigated the suitability of water hyacinth as a bulk substrate for growing a newly domesticated local oyster mushroom, Pleurotus flabellatus. The performance of the mushroom was investigated under ambient temperature and relative humidity (RH) regimes of 18-25/27-29 oC and 55-85/78-93%, respectively. The growth cycle of the mushroom was completed in 40 days with three and four flushes respectively. At the higher temperature and RH regime, the mushroom grew faster and the …

Antibacterial Activities Of Constituents From Isolona Cauliflora And Cleistochlamys Kirkii, Ac Odebode, Sjm Mdachi, Cc Joseph, Bn Irungu

Tanzania Journal of Science

Antibacterial activities of caulindole D, a mixture of caulindole E and F, pinocembrin and an oxyheptanoid (cleistenolide), obtained from stem barks of Isolona cauliflora and Cleistochlamys kirkii, on Staphylococcus aureus and Pseudomonas phaseolicola were determined. An in vitro assay test by paper disc method showed that the caulindole D, E and F from Isolona cauliflora produced no inhibition zone on both bacteria pathogens at 100-200 ppm while cleistochlamic acid from C. kirkii showed weak to moderate inhibition zone at 100-200 ppm. At concentration above 200 ppm, the bacteria pathogens were inhibited by all the compounds isolated from the plant extracts. …

Metal Concentrations In Sediment And Fish Of Lake Victoria Near And Away From Catchments With Gold Mining Acctivities, Jf Machiwa

Tanzania Journal of Science

Concentrations of metals in sediment and fish as well as organic matter contents of sediment from Lake Victoria were investigated. The objective of the study was to compare levels of metals in sediment and fish from areas of the lake that are within and outside catchments with gold mining activities.The results showed that the concentration of As was less than 6 mg g-1 dw and Cd was below 1.9 mg g-1 dw in sediment samples. Lead, zinc and copper concentrations were highest (58.1±17.6 mg g-1 dw, 101.9±20.6 mg g-1 dw and 32.6±2.8 mg g-1 dw respectively) in sediment samples that …

Salt Balance, Fresh Water Residence Time And Budget For Non-Conservative Materials For Makoba Bay During Wet Season, As Ngusaru, Aj Mmochi

Tanzania Journal of Science

Water and salt budgets suggest that in order to balance the inflow and outflow of water at Makoba bay, there is net flux of water from the bay to the open ocean during wet season. Residual salt fluxes between the bay and the open ocean indicate advective salt export. Exchange of water between the bay with the open ocean plays a role of replacing exported salt via mixing. Calculated freshwater residence time for the bay is 63 days during wet season. Budget results for non-conservative materials indicate net DIP flux from the ocean to the bay and a net DIN …

Concentrations Of Metals In River Sediment And Wetland Vegetations In Mining, Lake Victoria Basin, Tanzania, Jf Machiwa

Tanzania Journal of Science

Levels of metals were determined in river sediment, rice and sugarcane juice from Lake Victoria basin where small-scale gold processing activities are carried out to assess levels of contamination. Concentrations of metals in river sediments were generally high in areas that were closest to gold ore processing sites. For instance, mercury was highest (36.3 ±12.8 mg/g dw) in river sediments of Tigiti River in Mugumu District. Other heavy metals (Cd, Pb, Zn and Cu) had highest concentrations (2.20±0.71, 208±19.3, 412±20.1 and 132.7±11.9mg/g dw, respectively) in sediment samples from Kagota. The concentration of arsenic was highest (985.0±67.2 mg/g dw) in Mugusu …

Synthesis Of Some Cis-4,4-Dimethyl-2-Isopropenylcyclopentane Derivatives As Potential Intermediates Towards The Protoilludane Skeleton, Sjm Mdachi

Tanzania Journal of Science

The three gem-dimethyl-substituted cyclopentane derivatives 1-(2-propionyl)-4,4-dimethyl-2-isopropenylcyclopentane, 2-isopropenyl-4,4-dimethylcyclopentanecarboxyaldehyde and 1-hydroxy- methyl-2-isopropenyl-4,4-dimethylcyclopentane have been synthesized employing a thermally induced ene reaction as a key step. Each of the three compounds has been obtained predominantly as the cis isomer. The successful synthesis of these compounds affords opportunities for their further ellaboration towards sesquiterpenes of the protoilludane skeleton.

Ammonite Biostratigraphy Of The Jurassic Of Tanzania, S Kapilima

Tanzania Journal of Science

The present paper summarizes the previous biostratigraphical researches and incorporates the recent research findings on the Jurassic rocks in the coastal basin of Tanzania. The ammonites used for the biostratigraphical classification are from two sub-basins along the coastal belt of Tanzania: Mandawa (south) and Ruvu- Tanga (north). The oldest known ammonites from these basins are of Aalenian age. The biostratigraphical classification of the Jurassic sequence, on the basis of the vertical and horizontal distributions of the ammonite assemblages, permits the erection of eight sub stages of Jurassic: Upper Aalenian (Concavum-Zone), Bajocian (Humphrieasianum-Zone), Middle Callovian (Coronatum-Jason Zone), Upper Callovian (Lamberti-Athleta Zone), …

Bajocian Ammonites From Msata Hill (Lugoba Formation) In The Hinterland Of Dar Es Salaam, Tanzania, S Kapilima

Tanzania Journal of Science

Ammonites from the Middle Jurassic exposures of the Lugoba Formation at Msata, are described for the first time in Tanzania. Out of a number of ammonite fragments recovered from the bluish-green silty limestone (M3), only three fragments were fairly well preserved to permit their specific identification. Two species were identified: Dorsetensia cf. D. romani (OPPEL) and Oecotraustes (Paroecotraustes?) cf. angustus DOUVILLE. This ammonite assemblage is biostratigraphically correlatable with the Lower Bajocian Posidonia shale of the Kambe Limestone series in Kenya, in which similar ammonites species and other related Bajocian species have been described. Pending new discovery of ammonoid fauna and …

Petrology And Lithogeochemistry Of The Mineralized Tanzanite-Grossular Bearings Rocks In The Merelani-Lelatema Area, Northeastern Tanzania, Ep Malisa

Tanzania Journal of Science

The Merelani-Lelatema area, which is occupied by late Proterozoic metasedimentary rocks, lies along the Lelatema fault zone. The rocks are mainly pelitic and semi-pelitic gneisses, psammitic gneisses, hydrothermally altered rocks, crystalline dolostones, pegmatites and quartz veins. The occurrence of gem-quality tanzanite and grossular has been found to occur mainly in boudinaged pegmatitic veins and hydrothermal fracture fillings. These fracture fillings occur in brecciated and hydrothermally altered graphite-bearing gneiss in a mineral association containing glass-clear quartz, diopside, zoisite, graphite and calcite. The psammitic gneisses are more siliceous and enriched in feldspars. They are grouped into graphite-kyanite gneiss with thin interlayers of …

Southern Alumni, Siu Alumni Association

SIU Alumni Magazine

No abstract provided.

Postcolonial African Consciousness And The Poetry Of Agostinho Neto, Irene Marques

CLCWeb: Comparative Literature and Culture

In her paper, "Postcolonial African Consciousness and the Poetry of Agostinho Neto," Irene Marques introduces the magic words of a great poet with the question: can poetry carry enough sorrow, enough strength, enough fire, enough love, enough wisdom, enough care, and enough horror to penetrate the hearts and the souls of the oppressed and the oppressors so that both will desperately want to escape their sinister labels? For Marques, this question represents an old quandary and one that many of us wish could be answered with a simple yes. Marques analyses Neto's poetry in the context of littérature engagé: if …

The Daily Egyptian, November 07, 2003, Daily Egyptian Staff

November 2003

No abstract provided.

The Courier, Volume 37, Issue 4, October 24, 2003, The Courier, College Of Dupage

The Courier

Stories:

New President Investiture Today

It Should Not Happen Here

Books Are Relocated For Mold Removal

African Empowerment

Poor Concert Attendance Troubles SAPB

On To The Championship (women’s soccer)

People:

Sunil Chund

Aminata Tal Lo

Mark Mailer

Gus Williams

Shane Orlow

Ashley Brown

September 29, 2003 Reporter, University Of Alabama At Birmingham

eReporter (campus newsletter)

No abstract provided.

Some Remarks On The Use Of Force Against Terrorism In Contemporary International Law And The Role Of The Security Council, Jaume Saura

Loyola of Los Angeles International and Comparative Law Review

No abstract provided.

Makau Task Force Report - Overview, Truth, Justice, And Reconciliation Commission

II. Pre TJRC Documents

No abstract provided.

Makau Task Force Report, Truth, Justice, And Reconciliation Commission

II. Pre TJRC Documents

No abstract provided.

August 25, 2003 Reporter, University Of Alabama At Birmingham

eReporter (campus newsletter)

No abstract provided.

From The International Criminal Tribunal For Rwanda To The International Criminal Court: Expanding The Definition Of Genocide To Include Rape, Alexandra A. Miller

Penn State Law Review (2003 - Present)

No abstract provided.