Neutron spectrum parameters in two irradiation channels of the Nigeria research reactor-1 (nirr-1) for use in k0-naa

For the utilization of the NIRR-1 to include the k0-standardization method, the following neutron spectrum parameters in one inner and one outer irradiation channels were determined using the “Cd-ratio for multi-monitor method”: The thermal to epithermal flux ratio, f, and the epithermal flux shape factor, α. These parameters determined in the inner irradiation channel A1,are: α = - 0.046 ± 0.005 and f = 18.4 ± 0.34 and for the outer irradiation channel A2 α = + 0.024 ± 0.002 and f = 49.5 ± 0.96. The results compare well with reported values obtained from other reactor facilities with similar core configuration such as the Slowpoke and Miniature Neutron Source Reactor facilities available in literature

Determination of neutron-induced activation cross sections using nirr-1

Thermal Activation cross-sections for the (n, γ) reaction were experimentally measured using NIRR-1 facilities. The irradiated target isotopes were 71Ga, 109Ag, 55Mn 94Zr; 96Zr; 238U, 74Se, 75As and 48Ca. In order to obtain reliable activation cross sections, careful attention was paid to neutron irradiation and to the measurement of induced activity. The values obtained for the ten (n, γ) reactions were compared against the comprehensive evaluated values listed in Mughabghab, (2003) and other evaluated data libraries. The values were found to compare well with values evaluated by Mughabghab and those from other libraries

Evaluation of the Activity Concentration of 40K, 226Ra and 232Th in Soil and Associated Radiological Parameters of Shanono and Bagwai Artisanal Gold Mining Areas, Kano State, Nigeria

No Abstract

Multi-elemental analysis of some Nigerian mineral rocks for a comparative assay of gamma shielding with concrete using winxcom

Analysis of chemical composition and concentration of three Nigerian minerals have been carried out with the research reactor (GHARR-1) at Ghana Atomic energy commission Kwabenya Accra, in order to analyze their gamma photon shielding prospects using WINXCOM software. The physical densities of Serpentinite rock from Katsina/ Zamfara state, Hematite rock from Kogi state and Barite from Benue states of Nigeria were measured, and their moisture content analyzed with the Am-Be neutron source irradiation facility at Centre for Energy Research and Training (CERT) A.B.U. in Nigeria Qualitative and quantitative evaluation of gamma ray spectra of the residual radio nuclides of the rock samples were performed using the SPAN 5.0 software. The result of the chemical composition was observed to have a good elemental correlation with the well known neutron shields (concrete), but indicative of a better substitute to ordinary concrete when, in addition, the moisture retention capabilities, refractive properties and, most importantly, their densities are taken into account. The knowledge of the elemental composition is a requirement for calculating the shielding characteristics using WINXCOM. For an increase in photon energy by a factor of 0.21keV the mass attenuation in Serpentinite decreased by 2.0cm2/g; Hematite had a decrease of 5.0cm2/g; Barite also decreased by 5cm2/g while concrete had its mass attenuated by only 1.3cm2/g. Keywords: Transmission, Reflection, Mineral rock, Thermal neutrons, Fast neutrons, Moistur

Investigation on the Effects of Addition of Binder and Particle Size on the High Calorific Value of Solid Biofuel Briquettes

The effects of biomass particle size and addition of binder on the high calorific values (HCVs) of five (5) selected biomass briquettes is studied. Analyses of the experimental results show that finely grinded particles (about 1.75mm and 2.00mm) had low calorific values as the grinding resulted in a loss of some heat and made the sample vulnerable to air oxidation.Addition of gum Arabic binder greatly inceases the high calorific value of all samples followed by starch and top-glue binder tend to decerease the HCVs for the range of biomass tested in the order 25.3201> 23.2985>20.0023 respectively.Thus indicating gum Arabic and starch improves the caloric value while top glue and polyvinyl Chloride (PVC) decreases the calorific value of the samples. An extensive investigation on the PVC dissolved in Toluene compound(organic) as chemical binder was observed to decrease the calorific values of all the briquette samples except those made of coconut shell and rice husk. Keywords: Biomass, Biofuel, Binder, Briquette, High heating valu

Measurement of Radon Concentration in Water Sources around Ririwai Artisanal Tin Mine Kano State, Nigeria

In this work liquid scintillation analysis was used to measure the concentration of 222Rn in three sources of water around Ririwai Artisanal Tin mine. The annual effective dose due to 222Rn concentration in surface water source and Domestic water were also determined. The result shows that the tailing bearing water has the highest 222Rn concentration of 3.04±0.14 Bq/L followed by surface water source with 222Rn concentration of 2.51±0.13 Bq/L while the Domestic water has the lowest 222Rn concentration of 2.23±0.11 Bq/L. The results also indicated that the annual effective dose due to the 222Rn concentration is higher in surface water with 13.05±0.55 mSv/year than in Domestic water with 11.11 ± 0.44mSv/year. The mean 222Rn concentration obtained in this work is lower than 10.00Bq/L recommended by WHO and UNSCEAR. Also in this study the annual effective dose obtained is lower than the maximum permissible of 0.1mSv/year recommended by UNSCEAR. Keywords: Radionuclide, activity concentration and annual effective dos

Estimation of Human Health Risk Due to Heavy Metals around Schools and Auto-Mobile Workshops near Frequented Roads in Kaduna State, Nigeria

Heavy metals are widely known for their potential to cause carcinogenic and non-carcinogenic health risks. In this work, the carcinogenic and non-carcinogenic health risks associated with heavy metals in the vicinity of schools and auto mechanic workshops close to busy roads in Kaduna state was assessed using NEX CG EDXRF MODEL with brand name RIGAKU situated at a UTM Laboratory, Malaysia. The obtained heavy metals concentrations were used to estimate the health effects that might result from exposure to carcinogenic and non-carcinogenic chemicals for both the population ages using US EPA methodology. Findings indicated that in some locations the carcinogenic and non-carcinogenic hazards associated with exposure for residents was greater than the US EPA acceptable thresholds of 10-4 and 1 respectively. This indicated that the heavy metals may result to unacceptable carcinogenic and non-carcinogenic risks, which is an issue of concern in public health especially looking at the way school children play around these areas. The present study therefore provides scientific basis for strategies required to protect human and environmental health in schools and automobile workshops

DETERMINATION OF NEUTRON-INDUCED ACTIVATION CROSS SECTIONS USING NIRR-1

ABSTRACT Thermal Activation cross-sections for the (n, γ) reaction were experimentally measured using NIRR-1 facilities