Abstract A modification of Biot's pornelastic differential equi~tionsis made to include nrarrix-fluid interaction mech~ismsw hich assume n solid-fluid relaxation hnction coiipli~igc c~eflicient. Vulucs of physical propcrtics of scdi~iicntsn .rc incorporuted'into cqilationswhicl~d cfinc phnsc yelocity nnd attei~uatibnf or pcirous media which are dependent on the co~~posidteen sities of various medin (silt, and lnediu~na nd coqfse sand). The results enable us to coinpare tlie .atenuation and ve...
ABSTRACT Ionizing radiations resulting from either natural or artificial radioactivity are useful but associated with them are health risks which increase with exposure. The natural radioactivity levels in soils of some locations in Jos and Abeokuta are significantly higher than the world average. Enhanced internal and external radiation exposures to man may result from physical presence in, and ingestion of food items grown in these areas. Scientific data are sparse on the radionuclide conte...
Abstract Thls artlcle introduces Monte Carlomethds which are duerent from conrentio~nl ~mieticanl lethods andshow bow some of the methods can be applled in Physlcs,ro simrclate or solve physical proble~its. thtwr~hco rrilvrrer ~vrgrrrr>rr' (wrltten In FORTRAN In thls ca.r@, by ruing a few cxnml~lrrt oltchinff ,n doi.11 arid c/ns.~l[:olI 'lr~!!:ricrsh r~t~.rrr~s ~g r~lrfihess. A functional approach to probab//ity and statisticscl is describeJJor the p,1rynre o/tbn work r*.st~nd of comp/eto tre...
ABSTRACT Clays have some properties which make them good adsorbents. The adsorption of heavy metal ions by clay usually affects its thermal properties and these properties have direct influence on seed germination and crop growth. In this study, the variation of thermophysical properties of clay with adsorption of some heavy metal ions at different concentrations was investigated. An Atomic Absorption Spectrophotometer (AAS) was used to determine the concentrations in the samples. A known mas...
Abstract Reliable estimates of petroleum reserves are invaluable in reservoir management decisions and economic evaluation. Classical decline curve analysis techniques have been routinely used and are generally accepted in the industry to reliably estimate developed reserves up to a predetermined economic limit qec in oil wells. However Decline curve analysis techniques are based on the assumption that past production trends and their controlling factors will continue in the future and theref...
ABSTRACT A transition length is normally observed when fluid flows through a conduit before laminar flow is accomplished. This work examined a situation whereby porous materials were filled into the conduit and fluid was made to flow through. An attempt was made to determine this transition length for flow of water through riverbed sand of varying porosities filled into a horizontal cylindrical pipe of diameter 0.345 x m with piezomefric water head, set at 0.06m. The transition length was obs...
Abstract Presently, there are deep concerns over the environmental consequences and the consumption of non-renewable energy sources, with the accelerated greenhouse effect which triggered enormous interest in the use of renewable energy sources e.g. solar, hydropower, wind and geothermal. However, the intermittent nature of harvesting renewable energy sources has recently gained considerable attention in the alternative, reliable, cost effective and environmentally friendly energy storage de...
Abstract The High-Energy Stereoscopic System (H.E.S.S.) is an array of five imaging atmospheric Cherenkov telescopes located in the Khomas Highland in Namibia, dedicated to very-high-energy (VHE, 100 GeV – 100 TeV) gamma-ray astronomy. It consists of four identical 12 m diameter telescopes (H.E.S.S.-I) which started operating in 2003 and a large 28 m diameter telescope (H.E.S.S.-II) which was brought online in 2012 [1]. The H.E.S.S.-I camera upgrade project was aimed to increase the stabil...
ABSTRACT The hydrogeological system of the Ga East and Adentan Districts of the Greater Accra Region of Ghana was studied using numerical modelling on the Groundwater Modelling System platform (version 10.0). Historical hydrogeological data and groundwater monitoring data on twenty wells drilled in 2012 were relied on in conceptualising the hydrogeological system of the study area. A single aquifer system made up of quartzite-schist formation was identified. The borehole logs reveal four lith...
Abstract Pristine and transition metal (Fe, Mn, Co and Ni) doped ZnO powders were synthesised us- ing a hydrothermal method, and characterised by x-ray powder diffraction, ultraviolet-visible absorption spectroscopy, and photoluminescence (PL) emission spectroscopy. Synthesis was carried out at pH 3 and pH 5, and the powders annealed at 280 ◦C and 600 ◦C. Doping was done at concentrations of 1, 2, 4 and 8 mol %. Computational studies were also carried out on undoped and transition metal (...
ABSTRACT Microwave signal attenuation due to harmattan and rainfall are two of the major constraints in selecting microwave bands in Ghana. With customer complaints of signal loss during these seasons, telecommunication companies compensate for sudden losses in signal strength by amplifying the signal wave. This study investigates the effect of harmattan and rainfall on communication link for frequencies ranging from 10 to 100 GHz for two locations in Ghana, namely Axim and Tamale. Visibility...
Abstract This study concerns the application of a model-based approach for problem solving and conceptual understanding, in the context of kinematics, relating to the “foundation” component of an introductory physics course designed for students who are academically and scientifically underprepared. A new method for portraying objects in motion, “freeze frame” representation, was introduced. The particular visual conceptual model was employed as a representational bridge for translati...
ABSTRACT Refractive index is an important optical parameter that exhibits the optical properties of materials. Single-Diffraction Method (SDM) and Abbe’s Refractometer Method (ARM) have been used for the measurements of refractive indices of twelve water samples collected from different surface water sources in Namibia. SDM employs a diffraction grating, rectangular glass cell and Ne-He laser emitting a monochromatic light of 632.5 nm. Refractive indices of water samples were measured with...
ABSTRACT Aeromagnetic data of Nsukka and Udi areas were analyzed qualitatively and quantitatively. The study was aimed at mapping mineral deposits in a sedimentary basin, delineating susceptibility of rocks in the area, dip, plunge and type of body causing the magnetic anomaly and their trends as well as estimating the depth to magnetic source bodies. Spectral Analysis, Source Parameter Imaging (SPI), and Forward and Inverse modelling methods were used in the quantitative interpretation...
INTRODUCTION The physics design of nuclear reactors requires the determination of the gross statistical behaviour of the neutron population in the reactor system. This in turn calls for the solution of the Boltzmann equation of neutron transport theory which forms the subject matter of reactor theory. It is however not easy to solve this equation by a direct discretization process even on the largest computers because of the presence of too many independent variables, complicated energy varia...