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Tanzania Journal of Science

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Uplift And Erosion Of The Livingstone Basin Rift Flanks, Malawi (Nyasa) Rift, East Africa: Apatite Fission Track Analysis, Mbede E. I Dec 1995

Uplift And Erosion Of The Livingstone Basin Rift Flanks, Malawi (Nyasa) Rift, East Africa: Apatite Fission Track Analysis, Mbede E. I

Tanzania Journal of Science

Apatite fission track (AFT) dating is a method applied in neotectonic studies of sedimentary basin and in constraining uplift histories of rift flanks. Dating of 20 AFT samples of basement rocks flanking the Livingstone (Karonga/Tukuyu) basin on the northern edge of the Malawi (Nyasa) rift is used to analyse the uplift and erosionofthe basin flanks. Results suggest that in the Livingstone basin, rift-related uplift and erosion of the flanks has modified the topographic patterns. The high elevation of the Livingstone Mountains is related to regionally distributed isostatic rebound, whereas the topography of the hanging wall flank has probably been severely …

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Gravity Data Interpretation Of The Usangu Baisin Tanzania, I.M. Marobhe, E.I. Mbede Dec 1995

Gravity Data Interpretation Of The Usangu Baisin Tanzania, I.M. Marobhe, E.I. Mbede

Tanzania Journal of Science

The shape and geometry of Rift of basins is best expressed by looking at the depth to basement maps. It is now an accepted idea that the Rift basins are spoon shaped bounded on one side by a border fault (BF) which is normally the side of maximum sediment deposition. Gravity data from Usangu Basin collected by Amoco in 1985 are here interpreted to decipher the shape and the geometry of the Basin. Results suggest that the Usangu basin shape is similar to the other Rift Basins within the East African Rift System (EARS). The basin, is however, traversed by …

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Natural Zeolites For Pollution Control An Overview, M.M. Makweba Dec 1995

Natural Zeolites For Pollution Control An Overview, M.M. Makweba

Tanzania Journal of Science

Natural zeolites are minerals characterized by a framework of alumino-silicate whose structure contains channels occupied by water and exchangeable cations. The common known zeolites which occur in sedimentary rocks of volcanic origin include analcime, clinoptilolite, heulandite laumontite, philipsite, chabazite, erionite and mordenite. The zeolites have been studied in detail on their physical and chemical propertied. The ability of zeolite minerals like clinoptilolite to remove Cs-137 and Sr-90 from radioactive waste waters and to remove ammonium ions from municipal waste waters has been a milestone for zeolites to be applicable in pollution control. In Tanzania, zeolites occurrences have been reported in …

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Algal Stromatolites From The Late Permian Lacustrine Sediments Of Tanzania, C.Z. Kaaya Dec 1995

Algal Stromatolites From The Late Permian Lacustrine Sediments Of Tanzania, C.Z. Kaaya

Tanzania Journal of Science

Thin bed of algal stromatolites and oolites occur within a distinct stratigraphic unit (60-120 m thick) in the Late Permian (Karoo) lacustrine sedimetns of the Ruhuhu Basin in SW Tanzania. The stromatolites vary from a few centimeters to 50 cm high and exhibit 4 morphotypes: 1) bulbous or domal 2) columnar. Branching and non-branching varieties are common in the two morphotypes. The other two are : 3) laminated mats and 4) oncolites. All four types may occur in one bed. Filamentous algae were responsible for the building up of the stromatolites in which there was more precipitation of calcite than …

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Determination Of Tine In Geological Samples By Energy Dispersive X-Ray Fluorescence With A Secondary Target, J. M. J. Kahatano, M. Mwambeule Dec 1995

Determination Of Tine In Geological Samples By Energy Dispersive X-Ray Fluorescence With A Secondary Target, J. M. J. Kahatano, M. Mwambeule

Tanzania Journal of Science

Tin has been determined in seven international geochemical reference samples with energy-dispersive X-Ray Fluorescence using an X-ray tube with a secondary target, after optimization of the working parameters and instrument settings. The tin values obtained in this work quite satisfactorily lie within ranges reported in the literature or recommended by the suppliers of the reference samples. The method can therefore be applied to supplement other analytical techniques in the elemental analysis of geochemical samples.

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Physical Controls Of Mud Deposition In A Backbarrier System, Spiekeroog Island German Wadden Sea, N. Nyandwi Dec 1995

Physical Controls Of Mud Deposition In A Backbarrier System, Spiekeroog Island German Wadden Sea, N. Nyandwi

Tanzania Journal of Science

The areal distribution of the mean grain size of the sand fraction indicates presence of a shore-normal energy gradient with a shoreward fining from a mean grain size of 2.0 phi (0.25 mm) on Spiekeroog island to 3.5 phi (0.09) mm) near the dyke which forms the landward boundary of the tidal flat. This energy gradient is also reflected by the shoreward increase in the mud content of the sediment. Until recently, the relation of the mud distribution to the energy level variation in the Wadden Sea was not clearly known. Purely mud zones (˃ 50% mud) occur in the …

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Stratigraphy And Tectonic Evolution Of The Palaeoproterozoic Usagaran Belt In South-Eastern Tanzania, A.H. Mruma Dec 1995

Stratigraphy And Tectonic Evolution Of The Palaeoproterozoic Usagaran Belt In South-Eastern Tanzania, A.H. Mruma

Tanzania Journal of Science

The palaeoproterzoic Usagaran Belt is bordered by the Archaean Tanzanian Craton to the NW and the Mozambique Belt to the east. It is made up of the following three stratigraphic units:- (i) The lithodemic sillimanite, kyanite and cordierite gneiss lithodemes and pyroxene-garnet amphibolite lithodemes (ii) The lithostratigraphic Konse Group : greenschist to lower amphibolite facies metasedimentary and metavolcanic formations. (iii) The metavolcanic Ndembera Group; a possible lateral equivalent of the konse. Furthermore, the belt contains a post-tectonic gabbro-granitoid suite. The mutual stratigraphic relationship of the konse and Isimani has been a matter of dispute. However, the field observations described in …

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The Mozambique Of Eastern Tanzania: Evidence For Pan-African Reactivation Of Early Proterozoic Usagaran Basement, M.A.H. Maboko Dec 1995

The Mozambique Of Eastern Tanzania: Evidence For Pan-African Reactivation Of Early Proterozoic Usagaran Basement, M.A.H. Maboko

Tanzania Journal of Science

The high grade metamorphic rocks of Eastern Tanzania belong to two distinct tectonothermal belts; the early Proterozoic Usagaran Belt and the late Proterozoic (Pan–African) Mozambique Belt. Rocks of the Usagaran Belt, which locally sow evidence of eclogite facies metamorphism, experienced peak metamorphic conditions at ⁓ 2000 Ma. Tectonic activity in the Usagaran added at ⁓ 1800 Ma with the emplacement of post-organic granites. In contrast, the Mozambique Belt, which is characterized by extensive granulite complexes, experienced peak metamorphic conditions at about 700 Ma. Due to the similarity of both structural trends and metamorphic grade, the boundary between the two belts …

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Weathering On The Alkaline Rocks Of The Mbozi Gabbro Syenite Complex Sw–Tanzanian, East Africa, M.K.D. Mutakyahwa Dec 1995

Weathering On The Alkaline Rocks Of The Mbozi Gabbro Syenite Complex Sw–Tanzanian, East Africa, M.K.D. Mutakyahwa

Tanzania Journal of Science

The Mbozi gabbro syenite complex is about 800 Ma and is associated with the Bukoban tectonic episode. Tectonically it follows the regional strike direction of the Ubendian System, which is a part of the polycyclic Mozambique mobile belt. The complex is a typical ring structure with the central part down-faulted. Deep weathering profiles on the ring structure were developed on a peneplain and as a result of uplift intersected hilly landscape of early tertiary times. The truncated 5-15m thick weathering profiles occur on three rock types, olivine gabbro, pyroxenite and nepheline perthite syenite (pethoste). The chemical and mineralogical processes of …

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Palynostratigraphy Of Cretaceous Sediments, Rufiji Basin, Tanzania, E. Msaky Dec 1995

Palynostratigraphy Of Cretaceous Sediments, Rufiji Basin, Tanzania, E. Msaky

Tanzania Journal of Science

Cretaceous sediments from Luhio - 1 borehole drilled in the Rufiji basin yielded a palynomorph assemblage of spromorphs and dinoflagellate cyst species. The age of the sediments penetrated ranges from Early Cretaceous (Albian) to Late Cretaceous (Senonian). The Early Cretaceous is characterized by presence of the following dinocyst key species: Litosphaeridium arundum, Dinopterygium tuberculatum, Florentinia Cooksoniae, Systematophora cretacea and Oligosphaeridium pulcherrimum. The Late Cretaceous (Senonian) is characterized by the presence of the following dinocyst key species: Cannosphaeropsis utinensis, Dionogymnium pustulicostatum, Florentinia ferox, Odontochitina porifera, Odontochitina operculata, Xenascus sarjeantii and Xiphophoridium asteriforme …

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Silica Spherules In Chrysoprase From Haneti-Itiso Area, Cental Tanzania, E.P. Malisa Dec 1995

Silica Spherules In Chrysoprase From Haneti-Itiso Area, Cental Tanzania, E.P. Malisa

Tanzania Journal of Science

Apple green gem quality chrysoprase from haneti-Itiso area, central Tanzania was studied. Under the microscope the chrysoprase shows highly disordered spherules which are concentric. Composed of bipyramidal quartz, chalcedony quartzite and opal-A. The spherules were classified into four main types according to the shell arrangement. The diameter of the spherules ranged from 40 μm 77 μm. Fluid inclusion types in bipyramidal quartz were monophasic low temperature type. Mineralogical properties indicated refractive indices to be 1.548 to 1.553 (±0.002), mean specific gravity 2.56, hardness about 7 on Moho’s scale, inert to ultraviolet radiation, green though Chelsea filter, and absorption in the …

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Temperature-Based Predictions Of Wind Speed, Relative Humidity, Rainfall, Absolute Humidity, Vapour Pressure And Dew Point, E. C. Njau Dec 1993

Temperature-Based Predictions Of Wind Speed, Relative Humidity, Rainfall, Absolute Humidity, Vapour Pressure And Dew Point, E. C. Njau

Tanzania Journal of Science

We derive from first principles analytical expressions that give each of the following meteorological parameters in terms of (air) temperature: wind speed, relative humidity, rainfall, absolute humidity, vapour pressure and dew point. The practical validity of these expressions has been clearly ascertained using past meteorological records. Since air temperature is one of the easiest meteorological parameters to predict (Njau, 1991, 1994), the derived analytical expressions are simple and convenient tools by means of which wind speed, absolute humidity, rainfall, relative humidity, vapour pressure and dew point may be predicted. In this paper we demonstrate and explain how the derived analytical …

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Aerosol Composition As A Function Of Particles Size, Y. I. A. Koleleni, R. Van Grieken Dec 1993

Aerosol Composition As A Function Of Particles Size, Y. I. A. Koleleni, R. Van Grieken

Tanzania Journal of Science

Analysis of air particulate matter for various particle diameters 0.25-0.5 mm: 0.5-1 mm; 1-2 mm; 2-4 mm; and 4-8 were performed to investigate the contribution of both fine and coarse particles in environmental content. The abundance in the highest percentage concentration relative to particle diameters has shown interesting diagonal pattern with most of the elements ranging within 0-2%; 0.20%; 20-40%; 40-70%: and 70-100% respectively for different particle sizes. For the lowest percentage concentration range it is within 0-20%. In general the sum of elemental concentration provides a significant important result as far as pollution studies are concerned.

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Mathematical Analysis Of Marketing Costs Of Agricultural Crops: The Case Of Coffee, C.B. Alphonce Dec 1993

Mathematical Analysis Of Marketing Costs Of Agricultural Crops: The Case Of Coffee, C.B. Alphonce

Tanzania Journal of Science

This paper describes a case study in which a zero one mixed integer linear programming model was formulated and used to analyze marketing costs of coffee marketed by Kagera Co-operative Union. The solution of the model indicated a potential decrease of about 18% in the marketing costs. It is hoped that the model can be applied to other crops.

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Seasonality Of Salinity, Temperature And Dissolved Oxygen In The Inshore Waters Of Zanzibar In Response To The Local Meteorological Conditions, S. M. Mohamed Dec 1993

Seasonality Of Salinity, Temperature And Dissolved Oxygen In The Inshore Waters Of Zanzibar In Response To The Local Meteorological Conditions, S. M. Mohamed

Tanzania Journal of Science

Salinity, temperature and dissolved oxygen of the coastal surface waters off the coast of Zanzibar were investigated. The water showed an annual variation in properties reaching their maximum temperature and minimum salinity towards the end of the northeast monsoon and their minimum temperature and maximum salinity towards the end of southeast monsoon. However, results also show that local meteorological conditions have a profound impact on the hydrography of the area.

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Meteostat Wefax Image Data Acquisition From The Weather Satellite Receiver, A. J. Mwambela, A. Purvis Dec 1993

Meteostat Wefax Image Data Acquisition From The Weather Satellite Receiver, A. J. Mwambela, A. Purvis

Tanzania Journal of Science

This paper describe the development and implementation of satellite image data acquisition interface board using a programmable peripheral interface device, the intel 8255 PPI, to be used between a secondary data weather satellite receiver and an IBM PC. Brief details of both hardware and software design implementation, to transfer and store data are given.

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Effect Of Various Control Regimeson Insect Pests And Seed Yield Of Beans, Chipungahelo G.S.E, A.K. Karel Dec 1992

Effect Of Various Control Regimeson Insect Pests And Seed Yield Of Beans, Chipungahelo G.S.E, A.K. Karel

Tanzania Journal of Science

The effect of various control regimes on insect pests and seed yield was studied in common (Phaseolis vulgaris L.) beans. Two varieties namely Selian Wonder and Canadian Wonder were used. Four treatments of insecticide were used namely, full control (control throughout the growing seasons), control before flowering, after flowering, and no insecticide application. Endosulfan 35EC was sprayed at the rate of 800 g A.l. per 500 l of water per application. In this study both pre-flowering and post flowering pests were important. They included Ootheca bennigseni, Maruca testulalis, Heliothis armigera and Anoplocnemis curvepes. In addition a number of less …

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Theoretical Analysis Of Thermodynamic Consistency Of A Reiner-Rivlin Fluid, V.G. , Masanja Dec 1992

Theoretical Analysis Of Thermodynamic Consistency Of A Reiner-Rivlin Fluid, V.G. , Masanja

Tanzania Journal of Science

The thermodynamically admissibility of a Reiner-Rivlin fluid undergoing a two dimensional axisymmetric flow process has been investigated analytically. The Clausius-Duhem inequality shows dependence of the viscosity coefficients on kinematical quantities, hence no general restrictions can be made on the non-Newtonian viscosity coefficient. However specific restrictions have been made by considering a cubic degree fluid. It is concluded that the rheological equation of state is an approximate model of the constitutive behavior of a real fluid and that the thermodynamic consistency of a flow process can basically be proved numerically.

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An Account Of Sandbank Depositional Modes, Menai Strait U. K, N. Nyandwi Dec 1992

An Account Of Sandbank Depositional Modes, Menai Strait U. K, N. Nyandwi

Tanzania Journal of Science

Grain size distribution on the seabed and in the suspension were determined on an intertidal sandbank in Menai Strait, U.K. to establish both the mode of deposition and its stability against the strong tidal flows prevailing in the strait. Granulometric analysis showed typically three sediment population (log plot of cumulative curve) in the size range 4.0-3.0 phi and 1.5-1.0 phi with the middle on making the largest in all the samples. A probability plot of the cumulative curves however revealed on the average the lower (coarse) and upper (fine) truncation points to be lying at 1.5 phi and 3.0 phi …

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Surface Carbon Formation On Pt/ˠ-A12o3 From C3 And C4 Hydrocarbons Part 1: Kinetics Of Carbon Formation, L.L. Mkayula Dec 1992

Surface Carbon Formation On Pt/ˠ-A12o3 From C3 And C4 Hydrocarbons Part 1: Kinetics Of Carbon Formation, L.L. Mkayula

Tanzania Journal of Science

Carbon formation on an Esso reforming type catalyst Pt/γ-A12O3 by C3 and C4 hydrocarbons has been studied at atmospheric pressure and within a temperature range of 450-6000C using a microbalance capable of detecting up to 10-6 g by weight of coke. A kinetic model initially developed by Froment has been used to analyze the transient regime of coke versus time curves. Deactivation function-reaction mechanism relations have been proposed and applied to the coking results. Carbon deposition rates are highly dependent on temperature, partial pressures of reactant, nature and composition of reactions, and …

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Surface Carbon Formation On Pt/ˠ-A12o3 From C3 And C4 Hydrocarbons Part Ii: Characterization Of Coked Samples, L.L. Mkayula Dec 1992

Surface Carbon Formation On Pt/ˠ-A12o3 From C3 And C4 Hydrocarbons Part Ii: Characterization Of Coked Samples, L.L. Mkayula

Tanzania Journal of Science

The total surface area, pore size distribution, metal surface area, particle size and topography of coked Pt/γ-12O3 catalyst samples used in in part 1 of this series were measured and compared with those of a fresh catalyst. No significant changes in total surface areas of the coked catalyst was observed despite a high coke content in some samples. This is interpreted in terms of partial narrowing of mesopores that was confirmed by pore size distributions observations of high temperature coked samples. The platinum metal surface area of high temperature coked catalysts decreased with increase in temperature and …

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On The Entropy Of Kiswahili, Luhanga M.L, T.G.B. Nyambo Dec 1992

On The Entropy Of Kiswahili, Luhanga M.L, T.G.B. Nyambo

Tanzania Journal of Science

Cover and King’s gambling approach to the estimation of the entropy of English is used to estimate the entropy of Kiswahili. Experimental results obtained show that Kiswahili has average entropy of approximately 1.76.

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A Preliminary Chemical Survey Of The Salt Deposits And Evaporates Of Lake Balangida, Hanang District, Tanzania, N. Mwakoba, D. Mosha, K. Schrøder Dec 1992

A Preliminary Chemical Survey Of The Salt Deposits And Evaporates Of Lake Balangida, Hanang District, Tanzania, N. Mwakoba, D. Mosha, K. Schrøder

Tanzania Journal of Science

Lake Balangida is a typical salt-and –soda lake sharing many common hydrochemical features with the twenty or so hypersaline dischargeless lake of the African Gregory Rift Valley (Dead Sea to Lake Malawi). Sulphate content is however, comparatively exceptionally high but the single most contrasting dissimilarity is the virtual absence of fluoride. In previous reports, we have presented findings on the chemistry of the lake brines and inflows. In the present work, the salt deposits and evaporated which cover the lake after desiccation during the September-December dry spell are chemically examined. Salt and soda appear to occur in separate locations; the …

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Influence Of Previous Liming, N And P Fertilization Of An Oxisol On Grain Yield In Navy Beans, H. O. Mongi, A. P. Uriyo Jul 1975

Influence Of Previous Liming, N And P Fertilization Of An Oxisol On Grain Yield In Navy Beans, H. O. Mongi, A. P. Uriyo

Tanzania Journal of Science

A field study was initiated towards the end of the 1973 rain season to assess some residual effects of lime, N and P applications to a moderately acid Oxisol (initial pH 5.6; LR 10 tons/ha) on grain yield in navy beans, Phaseolus vulgaris L., grown soon following maize silage. The Oxisol was a sandy clay loam (35:13:52). The design was a split-plot, confounded factorial with 4 levels of lime at 0, 7.5, 10.0 and 12.5 tons agricultural lime/ha; N at 0, 100, 200 and 300 kg N/ha as ammonium sulphate; and P at 0, 40, 80 and 120 kg P/ha …

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Incorporation Trends Of (I-C14) Acetate In Pregnancy Lipids Of Various Organs, D.P. Sharma, T. A. Venkitasubramanian Jul 1975

Incorporation Trends Of (I-C14) Acetate In Pregnancy Lipids Of Various Organs, D.P. Sharma, T. A. Venkitasubramanian

Tanzania Journal of Science

Comparative evaluation of (I-C14) acetate incorporation was studied in ovary, adrenal, blood plasma and placenta in guinea pigs in mid pregnancy. The respective level of incorporation within the sample for total lipids did not differ in pregnancy and non-pregnant states. Placental lipids in general, and phospholipids in particular were highly incorporated in contrast to other organs/tissues. Amongst non-pregnancy total lipids, the blood plasma showed an elevated incorporation over ovarian and adrenal lipids. The ovary in pregnancy revealed depressed incorporation in general, except for esterified cholesterol which contained higher incorporation.  Phosphatidyl choline in adrenal, and phosphatidyl ethanolamine in blood plasma appeared …

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Chromosome Numbers Of Angiosperms In Tanzania, L.S. Gill, F.L. S Jul 1975

Chromosome Numbers Of Angiosperms In Tanzania, L.S. Gill, F.L. S

Tanzania Journal of Science

Chromosome Numbers of 30 taxa of angiosperms from Tanzania are reported. Of these, counts of 8 species are new. The occurrence of B-chromosome in Ornithogalum longibracteatum is reported for the first time.

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Contributions To The Knowledge Of The Mydis (Crustacea) From The Tanzanian Waters, Mihai Bacescu Jul 1975

Contributions To The Knowledge Of The Mydis (Crustacea) From The Tanzanian Waters, Mihai Bacescu

Tanzania Journal of Science

This is the first study on Mysids from the Tanzanian coast waters, in which, on the basis of material captured by himself, the author deals with some species belonging to the subfamily of Gastrosaccidae and Mysinae. Of the about 20 species identified so far in the collected material, five are new, namely: Gastrosaccus  msangii n.sp.; Anisomysis kunduchiana n.sp.; Tenagomysis tanzaniana n.sp.; Anisomysis sirielloides n.sp. and Mysidopsis coralicola n.sp. and six others are new to the area. Ecological and ethological data concerning all species mentioned are given.

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On The Field-Induced Infra-Red Absorption Of Gaas, Frederick Ngawo Onyango Jul 1975

On The Field-Induced Infra-Red Absorption Of Gaas, Frederick Ngawo Onyango

Tanzania Journal of Science

A theoretical survey of electric field–induced effects on one-and two-phonon absorption of GaAs is presented. The eigen-values and hence eigen-vectors are calculated for an external field applied along [001] and dependence of electro–absorption on the direction of radiation polarization established.

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Trials With Trickle Irrigation Equipment At Morogoro Preliminary Report, M.E. Parkes, M. E. Madata Jul 1975

Trials With Trickle Irrigation Equipment At Morogoro Preliminary Report, M.E. Parkes, M. E. Madata

Tanzania Journal of Science

The use of trickle irrigation is discussed with reference to Tanzania. A split-split plot design experiment is described in which yields of tomato, onion, and cabbage are compared for trickle and hand-irrigated plots, with different levels of fertiliser treatment. Yields for trickle-irrigated plots were significantly greater only for tomatoes. These results were achieved during July to October and a second attempt to grow the same vegetables during December to March was unsuccessful. Further trials are required to obtain a suitable rotation of vegetable crops from both a nutritional and agronomic point of view. Experience with the trickle irrigation equipment is …

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Theoretical Evaluation Of Selective Radiation–Absorbing Surface, K.R. O’Shea Jul 1975

Theoretical Evaluation Of Selective Radiation–Absorbing Surface, K.R. O’Shea

Tanzania Journal of Science

An algol computer program is described, by means of which the spectral reflectivity for any angle of incidence may be calculated for a surface consisting of up to two thin absorbing films on a bulk substrate. The values of optical constant, n and k, for the materials used and also the thickness of the films, are the only data required. Calculated reflectivities have been shown to be consistent with experimental results.

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