Physics

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Diurnal and annual cycles of surface refractivity and related parameters in Minna, Central Nigeria
(The Nigerian Journal of Space Research, 2011) O. D. Oyedum, J. A. Ezenwora, K. C. Igwe, J. O. Eichie and A. S. Moses
Radio refractivity N exerts considerable influence on radio signals at VHF and higher frequency bands. In particular, surface refractivity correlates positively with radio field strengths, and knowledge of its temporal variability is important in predicting performance of terrestrial radio networks, especially at VHF and microwave frequencies. Knowledge of the variability of the atmospheric parameters from which N derives is also important for radio propagation and other applications such as Agriculture and Tourism. Measurement of atmospheric parameters is also necessary to update past records, especially in the light of climate change. Surface refractivity values derived from values of air pressure P, temperature T and relative humidity H measured for two consecutive years (2008-2009) in Minna (09037N, 06032E),Central Nigeria are statistically analysed to explore their diurnal and seasonal cycles, as well as their inter-relationships. The results reveal that surface refractivity and the related weather variables show clear diurnal and seasonal trends with discernible relationships. In particular, diurnal N values have high correlation with diurnal P values, while monthly averages of N and H are also highly correlated; and the hot weather generally experienced in the month of April in Minna may be attributed to a combination of high humidity and high temperature at surface level.
NATURAL RADIOACTIVITY IN BOREHOLE WATER OF SOME WARDS IN MINNA, NIGER STATE
(2011-01-11) Kolo, M. T.,; Baba-Kutigi A. N.,; OLARINOYE, OYELEKE; Ibrahim. S.
28 samples o~ borehole water used for drinking and domestic purposes were sampled from three wards namely Bosso ward (A), Matkunkele ward (B), and Maitumbi ward (C) in Minna city, Niger State. The water samples were analyzed at the Center for Energy Research and Training, CERT, Ahmadu Beilo University Zaria, for their natural radioactivity content, using the Eurisis system-eight-:-channel-gas-filled proportional counter. The results obtained show that none of the samples from the three wards has gross alpha activity higher than the recommended guidelines by World Health Organization (WHO). The beta activity of two samples from ward B and four from ward C, however, shows a little elevation above the recommended screening level for potable water. The elevations notwithstanding, however, the overall results generally show that water from boreholes in the three wards is safe for drinking and other domestic purposes.
Variation of Effective Atomic Numbers of some Thermoluminescence and Phantom Materials with Photon Energies
(2011-05-15) OLARINOYE, OYELEKE
Effective atomic numbers (Zeff) of 15 materials (CaSO4, nylon, methyl but-3-enoate, mylar, C2F4, Al2O3, SiO2, stearate, CH4, CaF2, water, Iron sulphate, polystyrene, polyvinyl, and potassium calcium sulphate) used in dosimetry and substitute materials were calculated using standard formula based on their mass attenuation coefficients (µm). The µm of the materials were obtained for photon energies of 0.01 KeV to 20 MeV using WinXCOM. Generally, Zeff for each of the substances considered is not a constant but varies with photon energy. Zeff varies from11-17 for CaSO4, 3-6 for nylon, 6-7 for methyl but-3-enoate, 4-7 for mylar, 8-9 for C2F4, 10-12 for Al2O3, 10-12 for SiO2, 3-6 for stearate, 2-5 for CH4, 13-18 for CaF2, 3-8 for water, 12-23 for Iron sulphate, 4-6 for polystyrene, 5-16 for polyvinyl, and 1217 for potassium calcium sulphate. The variations of Zeff with photon energy for all the 15 substances follow similar pattern. The variations were dictated by photon interaction processes. The highest value of Zeff for all the materials was obtained at the lowest energy, while the lowest value was obtained between 0.1 and 1.5 MeV. The mean atomic number of each compound was also found to be equal to the Zeff obtained at intermediate energies of the energy spectrum considered (0.1 MeV -1.5 MeV). The upper and lower limit of Zeff for each of the considered materials was found to be dictated by the atomic numbers of the constituent elements of the materials
ASSESSMENT OF NATURAL RADIOACTIVITY LEVELS AND RADIATION HAZARDS IN THE TERTIARY INSTITUTIONS IN MINNA, NIGER STATE, NIGERIA.
(2012-01-15) Kolo, M. T.,; Baba-Kutigi, A. N.,; OLARINOYE, OYELEKE; Sharifat, I.
Activity concentrations of natural radionuclides in 30 surface soil samples collected across the three campuses of the two tertiary institutions in Minna, Niger State, Nigeria, were studied and evaluated. This survey was carried out using gamma spectrometric technique which employs NaI(Tl) gamma detector at the Center for Energy Research and Training (CERT), Ahmadu Bello University, Zaria, Nigeria. The mean values for the activity of 226Ra, 232Th and 40K were found to be 7.8±1.3Bqkg-1, 29.4±0.9Bqkg-1 and 229.4±1.8Bqkg-1 respectively. The activity profile of the primordial radionuclides in the soil samples investigated showed the existence of low level activity across the three campuses. The mean value of the annual effective dose equivalent obtained from this study is 0.04mSvyr-1, with mean external hazard index of 0.2. These average values fall within the internationally provided safety range for outdoor radiation exposure. The values obtained from this investigation for all the radiation parameters for the studied soil samples showed that none of the campuses investigated pose any significant radiological threat to the public.
Comparative assessment of natural radionuclide content of cement brands used within Nigeria and some countries in the world
(ELSEVIER, 2014) E.O. Agbalagba; R.O.A. Osakwe; OLARINOYE, OYELEKE
The gamma spectrometric analysis of different brands of cement used as building and construction material in Nigeria has been carried out in this study. Samples of 12 brands of gray Ordinary Portland Cement (OPC) and 5 brands of white cement of six samples each were collected and analyzed for their radiological content using gamma spectrometry method. The average value of 226Ra, 232Th, and 40K for OPC is 30.2 ± 10.4 Bq kg−1, 24.6 ± 7.1 Bq kg−1, and 251.3 ± 27.6 Bq kg−1 respectively and the average value for the white cement is 41.9 ± 16.7 Bq kg−1, 30.1 ± 9.4 Bq kg−1 and 340.2 ± 37.7 Bq kg−1 respectively. The total average content of 226Ra, 232Th, and 40K for all the cement brand samples are 36.1 ± 13.6 Bq kg−1, 27.4 ± 8.3 Bq kg−1, and 295.8 ± 32.7 Bq kg−1 respectively. These values obtained are lower when compared to the world average values(226Ra-50 Bq kg−1,232Th-50 Bq kg−1and40K-500 Bq kg−1)forbuildingmaterials.Theestimatedradium equivalent activities (Raeq), representative index (Iγ), average absorbed γ-dose rate (D), the annual effective dose rate (AEDE), annual gonadal dose equivalent (AGDE) external and internal hazard indices and the Excess life cancerrisk (ELCR)werelowerthantherecommendedsafelimitandarecomparablewithresultsfromsimilar studies conducted in othercountries. The evaluated mean gonadal dose equivalents of three cement brandsam ples were found to be higher than the world average for building material while others are less than the world average. A comparison of the average activity values obtained in Nigeria cement and other countries of the world show that those countries with history of high radionuclide solid minerals have activity concentration far above that of Nigerian cement, while these values agreed with those obtained in other countries.
Effect of Natural Dye Co-Sensitization on the Performance of Dye-Sensitized Solar Cells (DSSCS) Based on Anthocyanin and Betalain Pigments Sensitisation
(European Journal of Applied Sciences 9 (3): 140-146, 2017 ISSN 2079-2077, 2017-01-01) YUSUF Abubakar Sadiq; K.U. Isah; B.J. Jolayemi
Dye-sensitized solar cells (DSSCs) were prepared using natural pigments containing anthocyanin and betalain extracted from Flame tree and Bougainvillea glabra flowers respectively as sensitizers. The dyes were used as lone sensitizers exploring anthocyanin and betalain separately and as co-sensitizers exploring the combined anthocyanin and betalain (water extract) and combined anthocyanin and betalain (ethanol extract) separately. The effects of the sensitizers on the performance of the DSSCs were investigated, the study reveals that all the cells possess comparable values of V of about 0.55 0.1 V. However, of the two lone sensitisers,oc betalain based device gave a better efficiency of 0.21% while anthocynin based device achieved 0.17 %, this is attributed to their different anchoring functional groups. The, combined anthocyanin and betalain dyes (water extract) had the highest conversion efficiency of 0.26 % suggesting dye synergic absorption effect as a result of co-sensitisation, the lower efficiency of 0.24 %) achieved by combined anthocyanin and betalain (ethanol extract) is attributed to the contributory effect of the extraction solvents
Evaluating trap parameters of thermoluminescence glow-curves considering temperature dependent frequency factor
(2018) OLARINOYE, OYELEKE; SURAK KO; ADEBISI I
Assessment of shielding potentials and radiological safety indices of Nigerian granite rocks.
(NJTR FUTMINNA, 2019) OLARINOYE, OYELEKE; ALABI AA; SURAJ K
The activity concentration of primordial radioisotopes (238U, 232Th and 40K) in granite rock samples from Minna, North central Nigeria were measured using a sensitive HPGe detector for gamma spectrometric measurement. Five granite rock samples were collected from Maikunkele, Bosso, Maitumbi, Chanchaga and Paiko areas of the town. The average activity concentrations for the radionuclides in the rocks were: 27 ± 4 Bq/kg; 48 ± 7 Bq/kg and 874 ± 86 Bq/kg for 238U, 232Th and 40K respectively. The average absorbed dose rate, effective dose; radium equivalent (Req) and internal hazard index (Hin) were 65 ± 10 nG/h; 0.32 ± 0.05 mSv/y; 140 ± 21 Bq/kg and 0.45 ± 0.07 respectively. All the rock samples had Req less than the recommended safety value of 370 Bq/kg. All evaluated radiological safety indices fell within the recommended safety limits and world average values. The analysis of radionuclide content of the granite rocks showed that they do not pose environmental radiation risk to humans when used as structural shielding materials. Mass attenuation coefficients of the granite samples evaluated via the WinXcom computer code suggested that the granite rocks considered have good shielding capacity comparable to that of ordinary concrete.
Photon Absorption Buildup Factors for Different Concrete Types.
(2019) OLARINOYE, OYELEKE; MOHAMMED BELLO
Concrete is one of the most widely used materials for structural radiation shielding application. However, the shielding capacity of a concrete has been argued to depend largely on its constituent materials and sometimes its mass density. Hence concretes with different composite materials are expected to perform differently when used for shielding purpose. This research reports the estimation of the equivalent atomic numbers and photon Energy Absorption Buildup Factors (EABF) for eleven different species of concrete. The relationship between equivalent atomic number, density and EABF was also investigated. The concretes considered were categorized into light and heavy concretes based on their mass density. The EABF were calculated using the well-known geometric progression fitting procedure for photon energies from 0.015 MeV to 15 MeV and for penetration depth up to 40 mfp. An appreciable variation in the EABF was observed at different depth, energy and for each concrete type. The EABF were found to be high in the low and high energy regions and maximum in the intermediate energy section. The variation of EABF with energy and depth was attributed to the photoelectric, Compton scattering and pair production interaction modes. Although most high density concretes show lower buildup factor irrespective of depth and energy, an indication of good photon shielding coefficient. However, based on this study, it is the equivalent atomic number that can be best used to accurately compare the buildup factors amongst concrete rather than density.
EXABCal: A program for calculating photon exposure and energy absorption buildup factors
(ELSEVIER, 2019) OLARINOYE, OYELEKE; ODIAGA RAMOND; SILAS PAUL
This research presents a new Windows compatible program (EXABCal) for photon exposure and energy absorp tion buildup factors for standard energy grid from 0.015- 15 MeV for elements, mixtures and compound. This program was written using Python programming language and the calculation of buildup factors was based on the well-known Geometric Progression (GP) fitting procedure. The equivalent atomic numbers and GP fitting pa rameters of mixtures and compounds can also be evaluated using this program. The program has been used to evaluate the photon exposure and energy absorption buildup factors for standard energy grid from 0.015- 15 MeV for water, air and concrete, compared with values from the American Nuclear Society (ANS) standard reference data (ANSI-6.4.3) and found to be of high accurate with minimal errors. The program is fast and easy to use and will be of valuable interest to medical Physicist, radiation Physicists, Radiation shielding design engineers, stu dents, teachers and researchers and other experts working in areas where nuclear radiation is applied.
Mechanical features, alpha particles, photon, proton, and neutron interaction parameters of TeO2–V2O3–MoO3 semiconductor glasses
(ELSEVIER, 2020) OLARINOYE, OYELEKE; El-Agawany FI; El-Adawy, A., & Rammah, Y. S.
Mechanical properties, alpha particles, gamma-ray, proton, and neutron interaction parameters of 40TeO2-(60 x)V2O5-xMoO3:20≤ xMoO3 ≤60mol%(TVM20-TVM60) semiconductor glasses have been investigated. Based on Makishima–Mackenzie's model, the total ionic packing density (Vt) and the total dissociation energy (Gt) for TVM-glasses have been computed. Elastic moduli, hardness, and Poisson's ratio haven been calculated. Utilizing WinXcom and EXABCal computer codes, mass attenuation coefficient (MAC), linear attenuation coefficient (LAC), half value layer (HVL), mean free path (MFP), effective atomic number (Zeff), equivalent atomic number (Zeq), energy absorption and exposure built up factors (EABF and EBF), and fast neutron removal cross section ∑R have been computed. Results reflected that the (Vt) of the TVM-glasses varied from 0.597 to 0.610 (m3/mol), while the (Gt) increased from 63.36 × 106 to 63.48 × 106 (KJ/m3) for TVM20 to TVM60 glasses. The highest elastic features were found for TVM60 glass sample with highest value of MoO3 content. The elastic properties varied from 75.77 to 77.45 GPa for Young's modulus, from 54.67 to 56.70 GPa for bulk modulus, and from 0.267 to 0.272 for Poisson's ratio. The TVM60 glass sample possess the highest MAC, followed by TVM50, TVM40, TVM30, and TVM20, respectively. The maximum HVL was obtained at 8 MeV for all glass samples with values of 5.75, 5.30, 5.05, 4.71 and 4.31 cm for TVM 20, TVM30, TVM40, TVM50, and TVM60, respectively. The TVM60 has a better fast neutron shielding capacity compare to the other glasses. The relative difference between EABF and EBF of the glasses were in the order TVM20 > TVM30 > TVM40 > TVM50 > TVM60. Wecansaythat TVM60 glass can attenuate more photons than TVM20-TVM50 glasses.
Comparative analysis of NORM concentration in mineral soils and tailings from a tin-mine in Nigeria.
(2020) ATIPO M; OLARINOYE, OYELEKE; OB AWOJOYOGBE
Mining of tin and other related activities have been active and thus leading to economic growth in the Jos area of Nigeria for more than a century. However, mining of minerals has been confirmed to enhance the concentrations of heavy metals and natural radioisotopes in the soil, air and water bodies in the environment. In an attempt to evaluate the radiological burdens resulting from tin mining activities at Rayfield-Du area of Jos, specific activities of naturally occurring radioactive nuclei (238U, 232Th and 40K) concentrations were evaluated in soil samples collected from the mine site. The soil samples were classified as normal soil (S), tailings (T) and mineral soils (M) and their corresponding mean activities for 238U, 232Th and 40K were analysed using an HpGe detector-based gamma spectrometric system. The mean activity concentration for 238U, 232Th and 40K were 323.44, 877.63 and 864.99 Bq/kg, 138.84, 469.31 and 578.65 Bq/kg and 168.83, 436.08 and 346.1 Bq/ kg, respectively for M, T and S samples. The calculated radiation dose parameters for the soil samples were all higher than the recommended safety limit. For all the collected soil samples, the external hazard risk Hext were 2.21, 2.81 and 4.44 for S, T and M, respectively while the mean calculated radium equivalent was 819, 1057 and 1645 Bq/kg for S, T, and M, respectively. The excess lifetime cancer risk estimated for the mine was more than the world average value. The radio-ecological dose rate estimate for non-human biota in the mine revealed that all non-human species except lichen and bryophyte had absorbed dose rate less than the 10 µGy/h screening dose.
Mechanical and Gamma Ray Absorption Behavior of PbO‐WO3‐Na2O‐MgO‐B2O3 Glasses in the Low Energy Range
(2021) Aljawhara H. Almuqrin; Badriah Albarzan;; OLARINOYE, OYELEKE; Ashok Kumar; Norah Alwadai
The Makishima and Mackenzie model has been used to determine the mechanical prop erties of the PbO‐WO3‐Na2O‐MgO‐B2O3 glass system. The number of bonds per unit volume of the glasses (nb) increases from 9.40 × 1022 to 10.09 × 1022 cm−3 as the PbO content increases from 30 to 50 mol%. The Poisson’s ratio (σ) for the examined glasses falls between 0.174 and 0.210. The value of the fractal bond connectivity (d) for the present glasses ranges from 3.08 to 3.59. Gamma photon and fast neutron shielding parameters were evaluated via Phy‐X/PSD, while that of electrons were calculated via the ESTAR platform. Analysis of the parameters showed that both photon and elec tron attenuation ability improve with the PbO content. The fast neutron removal cross section of the glasses varies from 0.094–0.102 cm−1 as PbO molar content reduced from 50–30 mol%. Further anal ysis of shielding parameters of the investigated glass system showed that they possess good poten tial to function in radiation protection applications.
Investigations on borate glasses within SBC-Bx system for gamma-ray shielding applications
(2021) Y.S. Rammah; H.O. Tekin; C. Sriwunkum; OLARINOYE, OYELEKE; Amani Alalawi; M.S. Al-Buriahi; T. Nutaro; Baris T. Tongu
This paper examines gamma-ray shielding properties of SBC-Bx glass system with the chemical composition of 40SiO2e10B2O3exBaOe(45-x)CaOe yZnOe zMgO (where x ¼ 0,10, 20, 30, and 35 mol% and y¼z¼6mol%).Massattenuation coefficient (m=r) which is an essential parameter to study gamma ray shielding properties was obtained in the photon energy range of 0.015e15 MeV using PHITS Monte Carlo code for the proposed glasses. The obtained results were compared with those calculated by WinXCOM program. Both the values of PHITS code and WinXCOM program were observed in very good agreement. The m=r values were then used to derive mean free path (MFP), electron density (Neff), effective atomic number (Zeff), and half value layer (HVL) for all the glasses involved. Additionally, G-P method was employed to estimate exposure buildup factor (EBF) for each glass in the energy range of 0.015e15 MeV up to penetration depths of 40 mfp. The results reveal that gamma-ray shielding effec tiveness of the SBC-Bx glasses evolves with increasing BaO content in the glass sample. Such that SBC B35 glass has superior shielding capacity against gamma-rays among the studied glasses. Gamma-ray shielding properties of SBC-B35 glass were compared with different conventional shielding materials, commercial glasses, and newly developed HMO glasse. Therefore, the investigated glasses have potential uses in gamma shielding applications.
Gamma-Ray and Fast Neutron Shielding Parameters of Two New Titanium-Based Bulk Metallic Glasses
(2021) OLARINOYE, OYELEKE; CELESTINE OCHE
of being used for structural radiation shielding purposes. This study was conducted on two new low-density titanium (Ti)-based BMGs (i.e., Ti32.8Zr30.2Ni5.3Cu9Be22.7 and Ti31.9Zr33.4Fe4Cu8.7Be22) to investigate their photon and fast neutron shielding capacities. Material and Methods: The mass attenuation coefficients, half-value layers, effective atomic numbers, and exposure buildup factors of the two BMGs were calculated at the photon energy values of 15 keV and 15 MeV. Computation of mass attenuation coefficients and effective atomic numbers was accomplished using the XCOM and auto-Zeff software, respectively. In addition, the geometric progression procedure-based computer code EXABCal was used for calculating the exposure buildup factors of BMG. The fast neutron removal cross-sections were also calculated for the two BMGs. The calculated photon and fast neutron shielding parameters for BMGs were compared with those of lead (Pb), heavy concrete, and some recently developed glass shielding materials and then analyzed according to their elemental compositions. Results: The results showed that though Pb had a better photon shielding capacity, Ti-BMG attenuated photons better than heavy concrete. Furthermore, BMG had a higher neutron removal cross-section, compared to heavy concrete and some recently developed glass shielding materials. The neutron removal cross-sections of Ti32.8Zr30.2Ni5.3Cu9Be22.7 and Ti31.9Zr33.4Fe4Cu8.7Be22 were obtained as 0.1663 and 0.1645 cm-1, respectively. Conclusion: his study revealed that Ti-based BMG with high strength and low density have potential applications in high-radiation environments, particularly in nuclear engineering for source and structural shielding.
Shielding Properties of Some Marble Types: A Comprehensive Study of Experimental and XCOM Results
(2021) MohamedElsafi; Mohamed A.El-Nahal; Mayeen Uddin Khandaker; M. F. Alrashedi; OLARINOYE, OYELEKE; Hamid Osman; Sultan Alamri; M. I. Sayyed; and M.I.Abbas
In this work, some marble types were collected from Egypt, and their shielding characteristics were estimated. Their rigidity, in addition to their elegant shape, led us to consider their use as a protective shield, in addition to making the workplace more beautiful. The mass attenuation coefficient ( / ) was calculated for three types of marble (Breshia, Galala, and Trista) experimentally, using a narrowgammaraysourceandsodiumiodidescintillation detector (NaI). The results obtained were compared with the XCOM program and indicated a very good agreement between the two methods. The linear attenuation coefficient ( ) was evaluated to calculate the half and tenth value layers. The maximum value of 1.055, 1.041, and 1.024 cm 1 was obtained for Breshia, Galala, and Trista, respectively, at 0.06 MeV. The mean free path for studying the materials was compared with other shielding materials and showed good results at different energy scales. The energy absorption (EABF) and exposure buildup factors (EBF) were determined at different mean free paths. The fast neutron removal cross section R was calculated and expresses the ability of the marbles to slow down fast neutrons through multiple scattering. This is the ability of the marbles to shield fast neutrons.
Effect of CdO addition on photon, electron, and neutron attenuation properties of boro-tellurite glasses.
(ELSEVIER, 2021) Al-Buriahi, M. S., Hegazy, H. H., Alresheedi, F.,; OLARINOYE, OYELEKE; Algarni, H., Tekin, H. O., & Saudi, H. A.
This research article aims to study the effect of CdO addition on the radiation shielding characteristics of boro-tel lurite glasses in the composition of 50B2O3- (50-x) TeO2- xCdO, where x = 0, 10, 20, 30, 40 and 50 mol%. These glasses were exposed to gamma radiation and the transmitted gamma photons were evaluated for energies varying from 15 keV to 15 MeV using Geant4 simulation toolkit. The number of transmitted photons was then used to characterize the gamma shielding for the studied glasses in terms of linear/mass attenuation coefficients, MFP, Zeff, and HVL. The simulation outcomes were theoretically confirmed by using Phy-X software. The beta (electron) shielding characterization of the involved glasses was also investigated by determining the projectile range and stopping power using ESTAR software. Additionally, the fast neutron shielding characterization of the glasses was achieved by evaluating removal cross-section (ΣR). The results reveal that the CdO has a small influence on the shielding performance of the boro-tellurite glasses against gamma, beta, and neutron radiations. The shielding performance of the boro-tellurite glasses was compared with that of common shielding materials in terms of MFP. It can be concluded that the boro-tellurite glasses regardless of the concentration of CdO content have promising shielding performance to be used for radiation applications
Bi2O3 reinforced B2O3 + Sb2O3 + Li2O: composition, physical, linear optical characteristics, and photon attenuation capacity.
(ELSEVIER, 2021) Abouhaswa, A. S.,; OLARINOYE, OYELEKE; Kudrevatykh, N. V., Ahmed, E. M., & Rammah, Y. S.
Role of Bi2O3 on the structure, physical, linear optical characteristics, and radiation protection capacity of antimony borate–lithium with the form (65- x)B2O3 ? 10Sb2O3 ? 25Li2O ? xBi2O3 x = 0 (BSLB0), 4 (BSLB4), 8 (BSLB8), 12 (BSLB12), 16 (BSLB16), 20 (BSLB20) mol% glass systems was examined. The density was increased from 2.7125 to 3.9454 g cm-3 for BSLB0 and BSLB20 glass samples, respectively. The indirect optical bandgap decreases from 2.63 to 2.45 eV, while the direct optical bandgap decreases from 3.06 to 2.89 eV. Therefore, values of the refractive index (n) were varied from 2.50 to 2.56. Both optical (roptical) and electrical (relectrical) conductivities were enhanced with increasing Bi2O3 content in the investigated glasses. The observed trend of linear attenuation coefficient (LAC) values throughout the energy spectrum was followed the sequence: (LAC)BSLB20[(LAC)BSLB16[(LAC)BSLB12[(LAC)BSLB8[(LAC)BSLB4[(LAC)BSLB0 with values in the range of 0.052–14.469, 0.062–28.291, 0.070–42.738, 0.082–61.708, 0.091–79.616, and 0.104–102.154 cm-1 for BSLB0–BSLB20 glasses, respectively. At each energy within the energy spectrum, the mean free path (MFP) and half value layer (HVL) of the BSLB-glasses were decreased in the order of increasing Bi2O3 content in the glasses. The effective atomic number (Zeff) value varies from 6.53 to 15.12, 6.76–16.32, 7.02–17.37, 7.29–18.36, 7.58–19.29, and 7.89–20.16 for BSLB0BSLB20 glasses, respectively. Therefore, BSLB-glasses possess superior photon protection capacity than ordinary (OC) and barite (BC) concretes for photons.
SrO-reinforced potassium sodium borophosphate bioactive glasses: Compositional, physical, spectral, structural properties and photon attenuation competence
(ELSEVIER, 2021) Rammah, Y. S.,; OLARINOYE, OYELEKE; El-Agawany, F. I., Ibrahim, S., & Ali, A. A.
The melt quenching process is assumed in making the glass system 45P2O5-15B2O3-22Na2O-(18-x) K2O: xSrO where x =0-12 mol%, namely as S1-S5. Compositional, physical, spectral, structural properties and radiations attenuation competences of S1-S5 bioglasses have been investigated compared to ordinary concrete (OC) cortical bone (CB) and soft tissue (ST). The density of the prepared bioactive glasses has been found to increase with an increase in the SrO content, whereas an opposite trend has been observed in the molar volume. FTIR study shows the existence of different structural groups such as BO3, BO4 and BPO4 units in the network. Optical absorption spectra of the glasses revealed that the cutoff wavelength decreases with increased in SrO content. The maximum (minimum) MAC values were 7.986 (0.021), 7.925 (0.0214), 7.863 (0.0217), 7.865 (0.0217) and 8.837 (0.022) cm2/g for S1, S2, S3, S4, and S5, respectively. The maximum value of LAC was also obtained at 15 keV with values equal to: 18.528, 18.942, 19.343, 19.898, and 20.144 cm1 respectively for S1-S5. At 0.1, 1.0, and 10 MeV, values of HVT of the glasses were 1.72, 1.54, 1.38, 1.34, and 1.14 cm for S1-S5, respectively, however, the HVT of S1–S5 were less than that of ordinary concrete (OC). The MFP was reduced as SrO content of the S1-S5 glasses increased. Results of the calculated radiation interaction parameters showed that S5 is a better photon, proton and electron absorber compared to the other four bioactive glasses in this study. Improving in photon absorption of the glasses was recorded for higher SrO content. The effect of SrO addition on photon (energy) absorption is more significant for photon energies less than 0.2 MeV. The studied bioactive glasses can function better than ordinary concrete for photon shielding applications.
Determination of structural features of different Perovskite ceramics and investigation of ionizing radiation shielding properties.
(ELSEVIER, 2021) Slimani, Y., Hamad, M. K.,; OLARINOYE, OYELEKE; Alajerami, Y. S., Sayyed, M. I., Almessiere, M. A., & Mhareb, M. H. A.