ABSTRACT The NaI(TI) gamma-ray spectrometer was employed to determine the concentration of the naturally occurring Potassium(K-40). Uranium(U-238) and Thorium(Th-232) vis-a-vis the radiogenic heat production in soil samples from Idi-Omo farmland area of Akinyele Local Government area of Oyo state. The farmland which is at Latitude 070 30' 26.3" and Longitude 003" 5 7' 2 1.9" covers an area of about 80,000 square meter, and is at an average elevation of 240m above mean sea level (msl). The s...
Abstract Diurnal variation of vertical total electron content (VTEC) over Lagos, Nigeria (6.52° N, 3.399 E, dip latitude 3.03° S) during low solar activity period (2010) and a comparison with NeQuick-model-derived VTEC, are presented in this paper. VTEC generally increases from 0600 h LT and reaches its maximum value at approximately 1400 to 1700 h LT during all months considered. Our result shows that NeQuick model provide a good prediction during daytime and nighttime at Lagos, although s...
ABSTRACT Wave velocities in sand stones are greatly influenced by porosity and clay contents.
ABSTRACT This work considered the unsteady state drainage of fluid from a vertical column of porous material of varying porosities in an attempt to verify 'variation of drawn dawn surface with porosity and time using riverbed sand. Kerosene was used as the flowing fluid: Mathematical assumptions ware made in connection with Ducy's law.
ABSTRACT Experimental investigations have shown that variation of porosity and hydraulic gradient are responsible for the deviations from Darcy's law, which is perfectly obeyed only when the fluid flow is laminar in porous media. Previous attempts to modify this equation considered only the effects of porosity of surface-active materials such as clay in causing deviations from Darcy's law. In this study, both the effect of porosity of any porous medium and hydraulic gradient from recent exper...
ABSTRACT This paper presents the relationship between thermo f7hysical properties (thermal conductivity and thermal diffusivity) and heavy metal concentration of some surface clay from six local governments in Ibaaun, oyo state, Nigeria. An atomic absorption spectrometer (AAS) 1i1i)as used in analping the concentration of heavy metals present in each sample by .measuring the intensity of external radiation absorbed by the atom produced from the same sample at a wavelength characteristic to th...
ABSTRACT The movement of contaminated fluid from a solid waste landfill into a portable water aquifier located beneath is an example of underground flow.
ABSTRACT The phenomenon of detection of flow of water in porous media of different porosities with porosity ratio, is similar to the fact that there is deviation in fluid flow in a pair of media of different densities.
ABSTRACT Geophysical method was used to investigate the effects of Aba-Eku public refuse dumpsite in Ibadan on groundwater quality.
Abstract. We briefly present the motivation, architecture and usage experience as well as proof statistics for a new Rodin Platform proof back-end based on the Why3 umbrella prover. Why3 offers a simple and versatile notation as a common interface to a large number of automated provers including all the leading SMT-LIB and TPTP compliant tools. The plug-in can function either in a local mode when all the provers are installed locally, or remotely as a cloud service. We discuss the experience ...
Abstract An entry length is always observed before laminar flow is achieved in fluid flowing in a conduit. This depends on the Reynolds number of the flow and the degree of smoothness of the conduit. This work examined this region and the point where laminar flow commences in the context of flow through conduit packed with porous material like beads, of known porosity. Using some theoretical assumptions, it is demonstrated that permeability varies from zero at wall–fluid boundary to maximu...
ABSTRACT Many practical seepage and drainage problems can be studied by constructing flow nets for section with a single permeability, however many natural soil deposits are more or less stratified often with horizontal bedding that make horizontal permeability much greater than the vertical.
ABSTRACT This work presents the adsorption capacities of some heavy metals in clay soil and its application in medical field. Nitrate of lead solution of different concentrations were prepared (400ppm, 800ppm… 6400ppm). Each concentration of lead nitrate solutions was mixed with a known volume of clay. Slabs of regular dimensions were formed from the residue after it had gone through filtration. Each slab (dried) was irradiated with x-ray radiation at different energies; 40kev, 60kev, 80kev...
ABSTRACT Almost two thirds of the world's population lives within 400 km of the ocean shoreline; just over half live within 200 km, an area only taking up 10% of the earth's surface. As the world's population continues to grow at an alarming rate, fresh water supplies are constantly being depleted, bringing with it issues such as saltwater intrusion and increasing the importance of groundwater monitoring, management, and conservation. Constant monitoring of the fresh/salt water interface is n...
ABSTRACT The occupational exposure due to RF radiation leaks inside the base station cabin, when working on the Base station Transceiver (BTS) Radios and TX cables and during active radio communication was measured. A total of number 30 base stations Cabins were studied in the eastern part of Nigeria, using a Broad band TES-90 Electrosmog meter. The maximum instantaneous electric field strength obtained from GSM 1800 radio was 3.72 V/m, 16.56 V/m for GSM 900 radio and 11.29 V/m for the Tx ca...