Open Access Original Research Article

On the Bernoulli Equation in the Free Atmosphere and Mechanism of Long-lived Vortex Formation

Andrei Nechayev

Physical Science International Journal, Page 1-6
DOI: 10.9734/PSIJ/2016/28055

A new universal mechanism of the formation of long-lived atmospheric vortex is proposed. It is based on the hydrodynamic pressure drop in the air stream, if air density decreases in the flow direction. The magnitude of this drop may increase with jet velocity increasing. It is assumed that jet, linking the atmospheric layers with different air density, may have a local area of low pressure which can generate the vortex. The possible conditions for the emergence and intensification of atmospheric vortices of various types are discussed.

 

Open Access Original Research Article

Natural Radioactivity and Radiation Dose Estimation in Various Water Samples in Abua/Odua Area, Rivers State, Nigeria

C. P. Ononugbo, G. Tutumeni

Physical Science International Journal, Page 1-12
DOI: 10.9734/PSIJ/2016/28033

Gamma spectroscopy was used to determine the activity concentration of 238U, 232Th and 40K and radiation dose estimates in water resources of Abua/Odual Local Government Area in Rivers State of Nigeria. A total of 19 water samples (7 borehole water, 6 river water and 6 hand dug well) were collected from 7 districts of Abua/Odua area. The concentration of 238U, 232Th and 40K were measured by direct counting using sodium iodide [NaI(Ti)] detector interphased with a multi channel analyzer (MCA). The maximum activity concentration of 238U in borehole water, river and hand dug well were 11.58, 2.12 and 26.27 Bql-1 respectively. The mean activity concentration of 232Th in borehole water, river and hand dug well water were 46.21, 8.44 and 66.27 Bql-1 respectively while the activity concentration of 40K in borehole water, river and hand dug well water were 39.22, 47.47 and 609.8 Bql-1 respectively. The mean activity concentration of 40K is higher than 238U and 232Th in all the water samples. The committed effective dose was calculated for infants and adults population of the area. The mean committed effective dose for infants and adults that utilize borehole water were 3.21 and 10.25 mSvy-1 respectively. For infant and adult that use river water, the committed effective doses were 1.13 and 2.14 mSvy-1 respectively while those that consume hand dug well water were 3.11 and 7.36 mSvy-1 respectively. The doses estimated from the activity concentrations of radionuclide showed values within safe limits. Therefore, utilization of the water resources studied would not endanger the lives of the final users.

 

Open Access Original Research Article

The Impact of a Municipal Solid Waste Dumpsite on Soil and Groundwater Using 2-D Resistivity Imaging Technique

G. O. Itota, A. O. Balogun

Physical Science International Journal, Page 1-7
DOI: 10.9734/PSIJ/2016/28080

The impact of a municipal solid waste dumpsite on soil and groundwater in Port Harcourt municipality was investigated using 2-D resistivity imaging technique. The resistivity data was acquired along six traverses, two of which was used as control line. The objective of the study was to determine the lateral and vertical limits of leachate contamination. The results of the 2-D resistivity imaging for the four profile lines investigated isolated two possible pollutants zone around the landfill sites. The zone exhibit anomalously high resistive with varying resistivities between 264 Ωm and 3459 Ωm. This anomaly is deduced to be associated with landfill gases such as Ammonia, Methane, Sulphur (IV) oxide or Carbon (IV) oxide, at depths exceeding 31 m and contaminant leachate plumes of low resistivities having values that vary between 0.203 Ωm and less than 388.5 Ωm at depths between 0.625 m to more than 31 m. This resistivity plausibly suggests that the aquifers and soil in the area haves been contaminated by leachates due to the in an un-engineered landfill. However, the soil and groundwater beneath the control lines have not been impacted by the municipal waste landfill.

 

Open Access Original Research Article

Computational Study of 19.75% UO2 Fuel for the Core Conversion of Nigeria Research Reactor-1 (NIRR-1) from HEU to LEU

D. O. Samson, M. Y. Onimisi, A. Salawu, A. D. A. Buba, J. A. Rabba

Physical Science International Journal, Page 1-13
DOI: 10.9734/PSIJ/2016/23750

SCALE 6.1 code system and VENTURE-PC code system has been used for the core conversion of Miniature Neutron Source Reactor (MNSR) from Highly Enriched Uranium (HEU) system (90.2% enriched UAl4 fuel) to Low Enriched Uranium (LEU) system (19.75% enriched UO2-zircaloy-4 fuel). All other structure materials and dimensions of HEU and LEU cores are the same except the increase in the fuel cell diameters for the proposed LEU core. Results obtained show that the peak power density of 4.310033 Watts/cc, maximum neutron density of 6.94535e-6 n/cc, total control rod worth of pcm, clean cold core excess reactivity of pcm, of , shutdown margin of  pcm and neutron flux profile of  for the potential LEU core are slightly greater than those of the current HEU core. These results also indicate that the LEU core can operate perfectly in natural convection mode which shows the accuracy of the model and precision of the transport code system used. 

 

Open Access Original Research Article

Open Access Original Research Article

Frequency and Temperature Effect on Dielectric Properties of Acetone and Dimethylformamide

M. Y. Onimisi, J. T. Ikyumbur, S. G. Abdu, E. C. Hemba

Physical Science International Journal, Page 1-8
DOI: 10.9734/PSIJ/2016/27742

The dielectric behavior of both acetone and dimethylformamide (DMF) were examined in the presence of an electric field. The electrical conductivity of both solvents was used to estimate the complex permittivity of acetone and dimethylformamide. The relaxation time of the solvents at various temperatures was estimated. The experimental static permittivity values together with the estimated complex permittivity, and relaxation time were substituted in the Debye equations to generate the dielectric constant and the corresponding loss factor at various frequencies using maple-13 programme. Result for the dielectric constant indicates that at frequency 0.1 GHz and temperature 10°C, the calculated value for acetone was 22.4637 and that of DMF was 40.3380. This shows that an increase in dielectric constant caused a corresponding decrease in the loss factor, which means an inverse relation between the frequency and temperature. The result of calculations of the dielectric constant also compared well with the experimental values for both acetone and DMF at the same frequency temperature of  and   respectively.