Odoi H.C.,University of Ghana |
Akaho E.H.K.,Ghana Atomic Energy Commission |
Anim-Sampong S.,University of Ghana |
Anim-Sampong S.,Center for Energy Research and Training |
And 9 more authors.
Nuclear Engineering and Design | Year: 2011
Neutronics analyses were performed on the 30 kW(th) GHARR-1 facility to investigate the effects on increased beryllium annular reflector thickness on nuclear criticality safety and on the neutron flux levels in the experimental channels. The investigative study was carried out using the Monte Carlo code MCNP on a hypothetical LEU UO 2 core theoretically enriched to 12.6% and having the same core configuration as the present 90.2% enriched HEU U-Al core. The analyses were performed on four models consisting of a reference model with 10.2 cm annular reflector thickness and three new design modification models with increased reflector thickness of 10.3, 10.4 and 10.5 cm respectively. The simulations indicated average thermal neutron fluxes of (9.80 ± 0.0017)E+11 n/cm 2 s in the inner irradiation channels for the reference model, indicating a 2% decrease with respect to the nominal flux of 1.00E+12 n/cm 2 s. Relatively lower neutron fluxes were obtained for the modification models with an average of (9.79 ± 0.0017)E+11 n/cm 2 s, representing losses of 2.01% and 0.01% with respect to the HEU core and reference LEU model. © 2011 Elsevier B.V. All rights reserved.
Raimi J.,Ahmadu Bello University |
Dewu B.B.M.,Center for Energy Research and Training |
Sule P.,Ahmadu Bello University
Arabian Journal of Geosciences | Year: 2015
The study area lies within the north-western part of the Nigerian Younger Granite province. It is bounded by latitude 10°30′N and 11°00′N and longitude 8°00′E and 9°00′E. Previous geological and geophysical studies that were carried out in the study area focused mainly on the ring complexes with surface exposure while nothing is known about those without the surface exposure. This has resulted in gap in geo-scientific knowledge which this study aimed to fulfill. First vertical derivative (FVD) and Euler deconvolution of the aeromagnetic data along with processed DEM were used to achieve this purpose. Results of the interpretation revealed a magnetic anomaly, almost circular in shape, with characteristics that are similar to the anomalies that spatially coincide with the prominent ring complexes but without the outcrops that are associated with the complexes. This anomaly is interpreted to be an unexposed ring. Lineaments revealed by the results are mainly oriented in the E–W, NE–SW and NW–SE. The lineaments in the NE–SW and its conjugate are the most developed lineament system. Presence of ring complexes on and along the lineaments favours the opinion that the emplacement sites of the complexes are influenced by the reactivated Pan-African shear zones and transcurrent faults. In particular, the cross-over of major lineaments at the non-outcropping anomaly may suggest a very weak zone that probably allowed the volcanic eruption that initiated the emplacement of the unexposed ring complex. Results of the Euler deconvolution suggest a cylindrical-like body for the unexposed ring complex, which is consistent with pluton geometry, and a depth that range from outcrop to 1,200 m for it. © 2014, Saudi Society for Geosciences.
Ahmadu U.,Minna Federal University Of Technology |
Soje A.A.,Minna Federal University Of Technology |
Usman A.B.,Minna Federal University Of Technology |
Musa A.M.,Center for Energy Research and Training |
Isaha K.U.,Minna Federal University Of Technology
Processing and Application of Ceramics | Year: 2016
Barium calcium stannate titanate (Ba0.98Ca0.12Ti0.975Sn0.025O3) ceramics, synthesized by solid state reaction method and sintered at 1100 °C/3 h, were exposed to gamma radiation dose of up to 1 kGy using a Cs-137 irradiation source at a dose rate of 100.46Gv/h. Structural analysis of the ceramics indicated a tetragonal perovskite crystalline structure for both pristine and irradiated ceramics with a minor secondary phase. However, slight changes of the lattice parameters and average crystallite size were observed for the irradiated samples. The lattice aspect ratio of the tetragonal phase (c/a) for the pristine ceramics was 1.0022 which decreased by 0.22% at maximum irradiation dose. Irradiation also causes some microstructural changes and slight decrease in grain size. Energy dispersive spectroscopic investigation of the Ba0.98Ca0.12Ti0.975Sn0.025O3 showed small variation in its chemical composition as gamma radiation dose is increased.
Arabi A.S.,Center for Energy Research and Training |
Raimi J.,A.B.U. |
Dewu B.B.M.,Center for Energy Research and Training
International Journal of Applied Environmental Sciences | Year: 2011
A geoelectric survey involving Vertical Electrical Sounding was carried out to determine sites for construction of boreholes that will provide adequate water supply for extensive irrigation work at Kan-Kurmi, Kaduna state, Nigeria. The data were acquired with symmetric Schlumberger configuration at stations chosen across the study area. The acquired data were inverted with 1D Earth Imager iterative software. Information from a borehole was used as control for delineation of realistic geologic model of the study area. The interpreted results suggest four geoelectric layers. Their equivalent geologic/lithologic units suggest weathered and the underlain partially weathered/ fractured basement as the aquiferous layers of the study area. Suitable sites for construction of pump-fitted wells were suggested based on depth and thickness range of the aquiferous layers. © Research India Publications.