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Investigation of gamma radiation shielding capability of two clay materials
S.F. Olukotun,S.T. Gbenu,F.I. Ibitoye,O.F. Oladejo,H.O. Shittu,M.K. Fasasi,F.A. Balogun 한국원자력학회 2018 Nuclear Engineering and Technology Vol.50 No.6
The gamma radiation shielding capability (GRSC) of two clay-materials (Ball clay and Kaolin)of SouthwesternNigeria (7.49 N, 4.55 E) have been investigated by determine theoretically and experimentallythe mass attenuation coefficient, m/r (cm2g 1) of the clay materials at photon energies of 609.31, 1120.29,1173.20, 1238.11, 1332.50 and 1764.49 keV emitted from 214Bi ore and 60Co point source. The massattenuation coefficients were theoretically evaluated using the elemental compositions of the claymaterialsobtained by Particle-Induced X-ray Emission (PIXE) elemental analysis technique as inputdata for WinXCom software. While gamma ray transmission experiment using Hyper Pure Germanium(HPGe) spectrometer detector to experimentally determine the mass attenuation coefficients, m/r(cm2g 1) of the samples. The experimental results are in good agreement with the theoretical calculationsof WinXCom software. Linear attenuation coefficient (m), half value layer (HVL) and mean free path(MFP) were also evaluated using the obtained m/r values for the investigated samples. The GRSC of theselected clay-materials have been compared with other studied shielding materials. The cognizance ofvarious factors such as availability, thermo-chemical stability and water retaining ability by the claysamplescan be analyzed for efficacy of the material for their GRSC.
Neutron-shielding behaviour investigations of some clay-materials
S.F. Olukotun,Kulwinder Singh Mann,S.T. Gbenu,F.I. Ibitoye,O.F. Oladejo,Amit Joshi,H.O. Tekin,M.I. Sayyed,M.K. Fasasi,F.A. Balogun,Turgay Korkut 한국원자력학회 2019 Nuclear Engineering and Technology Vol.51 No.5
The fast-neutron shielding behaviour (FNSB) of two clay-materials (Ball clay and Kaolin)of SouthwesternNigeria (7.49 N, 4.55 E) have been investigated using effective removal cross section, SRðcm 1Þ, massremoval cross section, SR=rðcm2g 1Þ and Mean free path, l (cm). These parameters decide neutronshielding behaviour of any material. A computer program - WinNC-Toolkit has been used for computationof these parameters. The toolkit evaluates these parameters by using elemental compositions anddensities of samples. The proficiency of WinNC-Toolkit code was probe by using MCNPX and GEANT4 tomodel fast neutron transmission of the samples under narrow beam geometry, intending to representthe actual experimental setup. Direct calculation of effective removal cross section (cm 1) of the sampleswas also carried out. The results from each of the methods for each types of the studied clay-materials(Ball clay and Kaolin) shows similar trend. The trend might be the fingerprint of water content retainedin each of the samples being baked at different temperature. The compositions of each sample have beenobtained by Particle-Induced X-ray Emission (PIXE) technique (Tandem Pelletron Accelerator: 1.7 MV,Model 5SDH). The FNSB of the selected clay-materials have been compared with standard concrete. Thecognizance of various factors such as availability, thermo-chemical stability and water retaining ability bythe clay-samples can be analyzed for efficacy of the material for their FNSB.
Feasibility of clay-shielding material for low-energy photons (Gamma/X)
S.M. Tajudin,A.H.A. Sabri,M.Z. Abdul Aziz,S.F. Olukotun,B.M. Ojo,M.K. Fasasi 한국원자력학회 2019 Nuclear Engineering and Technology Vol.51 No.6
While considering the photon attenuation coefficient (m) and its related parameters for photonsshielding, it is necessary to account for its transmitted and reflected photons energy spectra and dosecontribution. Monte Carlo simulation was used to study the efficiency of clay (1.99 g cm 3) as a shieldingmaterial below 150 keV photon. Am-241 gamma source and an X-ray of 150 kVp were calculated. Thecalculated value of m for Am-241 is higher within 5.61% compared to theoretical value for a single-energyphoton. The calculated half-value layer (HVL) is 0.9335 cm, which is lower than that of ordinary concretefor X-ray of 150 kVp. A thickness of 2 cm clay was adequate to attenuate 90% and 85% of the incidentphotons from Am-241 and X-ray of 150 kVp, respectively. The same thickness of 2 cm could shield thegamma source dose rate of Am-241 (1 MBq) down to 0.0528 mSv/hr. For X-ray of 150 kVp, photons below60 keV were significantly decreased with 2 cm clay and a dose rate reduction by ~80%. The contributionof reflected photons and dose from the clay is negligible for both sources.
Rilwan U.,Aliyu G.M.,Olukotun S.F.,Idris M.M.,Mundi A.A.,Bello S.,Umar I.,El-Taher A.,Mahmoud K.A.,sayyed M.I. 한국원자력학회 2024 Nuclear Engineering and Technology Vol.56 No.7
This research intends to recycle bone and incorporate it into concrete for radiation shielding application using Phy-X/PSD software. Cement, sand and granite were mixed in proportion of 0.5 kg:1 kg:1 kg to obtain sample A. Other concretes composing of cement, sand, granite and bone ash was in proportion 0.45 kg:1 kg:1 kg:0.05 kg, 0.1 kg:1 kg:1 kg:0.4 kg and 0.35 kg:1 kg:1 kg:0.15 kg to obtain samples B, C and D respectively. 0.5 water-tocement (W/C) ratio was adopted throughout the mixes because the control mix contain the normal water quantity for normal hydration of cement. Replacing the bone ash for the cement in the fabricated concretes enhances their densities where the fabricated concretes’ density decreased from 2.33 g/cm3 to 2.22 g/cm3 by raising the reinforcing bones fly ash concentration from 0 to 0.15 kg. Additionally, increasing the bones fly ash concentration within the fabricated concretes increases their linear attenuation coefficient (LAC) where the fabricated concretes’ μ values at 0.662 MeV reach 0.181 cm 1, 0.178 cm 1, 0.174 cm 1, and 0.171 cm 1, respectively for concretes A, B, C, and D. The use of other local materials is recommended, as it improves waste management being the major aim of the sustainable development goal.