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Öğe Er 2 O 3 effects on photon and neutron shielding properties of TeO 2 -Li 2 O-ZnO-Nb 2 O 5 glass system(Elsevier B.V., 2019) Ağar, Osman; Kavaz, E.; Altunsoy Güçlü, E. E.; Kılıçoğlu, O.; Tekin, H.O.; Sayyed, M.I.; Ergüzel, T.T.In this study, a series of 75TeO 2 -5Li 2 O-10ZnO-(10-x)Nb 2 O 5 -(x)Er 2 O 3 (where x = 0, 0.5, 1.0, 1.5, 2.0 and 2.8 mol%) glasses have been surveyed in terms of photon and neutron shielding characteristics. For this aim, 3 × 3 inch NaI(Tl) detector has been simulated in order to detect photons. Afterwards, the mass attenuation coefficients (?/?) and some shielding quantities such as half-value layer (HVL), tenth value layer (TVL), mean free path (MFP), effective atomic number (Z eff ), effective electron density (N el ), equivalent atomic number (Zeq) and exposure build-up factor (EBF) have been calculated. The obtained MCNPX results of all the glasses have been compared and approved with those of XCOM program. Also, their gamma ray buildup factors have been determined in a wide energy range of 0.02–20 MeV for penetration depths up to 15 mfp. Moreover, neutron attenuation abilities of glasses have been evaluated by estimating neutron total effective removal cross section. The results showed that Er 2 O 3 partial replacement of Nb 2 O 5 in 75TeO 2 -5Li 2 O-10ZnO-(10- x)Nb 2 O 5 -(x)Er 2 O 3 glass system enhances photon and neutron attenuation characteristics. It can be deduced that obtained results from the present investigation can be useful to understanding of influence of Er 2 O 3 on nuclear radiation shielding properties of tellurite glasses.Öğe The investigation of gamma-ray and neutron shielding parameters of Na 2 O-CaO-P 2 O 5 -SiO 2 bioactive glasses using MCNPX code(Elsevier B.V., 2019) Tekin, H.O.; Kılıçoğlu, O.; Kavaz, E.; Altunsoy Güçlü, E. E.; Almatari, M.; Ağar, Osman; Sayyed, M.I.Bioactive glasses are silicate glasses with sodium, calcium and phosphorus in its composition used to fulfill or support the functions of living tissues in the human body. The superiority of physical and mechanical properties of the bioactive glasses leads to the opportunity to use for radiation protection. From this point of view, radiation absorption parameters of nine bioactive glasses were reported in the present research. The mass attenuation coefficient (?/?) for the selected bioactive glasses was calculated using MCNPX simulation code in the photon energy range 0.02–20 MeV and the results were compared with XCOM data. The values of ?/? calculated in two methods were found to support each other. Other vital parameters like half and tenth value layer (HVL and TVL), mean free path (MFP) and effective atomic number (Z eff ) for the selected bioactive glasses were also evaluated by utilizing the ?/?. ICSW9 glass with more phosphate and sodium contents possess the lowest MFP, HVL and TVL values while has the highest Z eff values among the bioactive glasses under study. To evaluate the neutron protection performance of investigated bioactive glasses, effective removal cross-section values (?R) have been determined. The results showed that ICSW9 has also superior neutron attenuation properties. Additionally, exposure buildup factor (EBF) values were found with G-P fitting approach depending on the energy and penetration depths. The bioactive glasses with further equivalent atomic number possesses the minimum value of EBF. © 2019 The AuthorsÖğe Investigations on structural and radiation shielding properties of Er 3+ doped zinc bismuth borate glasses(Elsevier Ltd, 2019) Prabhu, N.S.; Hegde, V.; Sayyed, M.I.; Ağar, Osman; Kamath, S.D.Novel optical glasses 10ZnO-5Na 2 CO 3 -10Bi 2 O 3 -(75-x)B 2 O 3 -xEr 2 O 3 with x = (0, 0.1, 0.3, 0.5, 0.7, 1.0) mol%, were synthesized by melt quench technique and characterized through XRD, EDAX, optical and luminescent properties, before and after irradiating them with high energy (1.3 MeV) gamma rays. Moreover, the gamma photons attenuation characterizations for the samples under study were studied. The mass attenuation coefficients for the selected glasses were affected with the addition of Er 2 O 3 . Based on the findings from the mass attenuation coefficients, ZNBBEr-5 has better photon attenuation features in comparison with the other samples. Also, arising the Er 2 O 3 content in the glasses, led to increase the effective atomic number. The mean free path for the prepared samples were compared with some shieling glasses. Shielding performance of the present glass samples against gamma radiation reveals pair production is prominent at 1.3 MeV. UV-VIS–NIR absorption edge was red shifted after gamma irradiation indicating the formation of electron/absorption centers in the glass matrix. Thermally stimulated Luminescence (TL) spectroscopy technique showed five electron trap centers at 445K, 491K, 545K, 590K, 620K with acceptable FOM [< 5%] values. The number of overlapping peaks and their trapping parameters like kinetic order, activation energy, peak temperature, frequency factor and half life were determined using the Computerized Glow Curve Deconvolution (CGCD). Linear behaviour obtained through the dose response of the glass (5 kGy–50 kGy) proved their suitability for dosimetric application in the food irradiation zones and in red LEDs (<50 kGy).Öğe Photon-shielding performance of bismuth oxychloride-filled polyester concretes(Elsevier, 2020) Sharma, Amandeep; Sayyed, M.I.; Ağar, OsmanThe preparation of materials with high attenuation performance is one of the major issues in the radiation shielding applications. This study is based on the investigation of gamma-shielding characteristics of Bismuth (III) Oxychloride (BiClO) doped polymer concretes. In the produced polymer composites, unsaturated polyester, BiClO, methyl ethyl ketone peroxide (MEKP) and cobalt octoate 6% (CO-6) are chosen as resin, filling material, initiators and accelerators, respectively. The radioactive point-isotropic sources Na-22, Mn-54, Co-57, Co-60, Ba-133, (CS)-C-137, (EU)-E-152 and Am-241 with energies varying from 59.5 keV to 1408.0 keV were used and gamma spectrometer based HPGe detector were employed for the investigation. The obtained experimental data were compared with those of FLUKA code results as well as with XCOM results. We found that the attenuation coefficient values of the studied concretes were in good agreement with the results of other approaches at the investigated energies. BiClO (20%), which is the end-point of compositions studied, has the best radiation shielding property among the prepared polyester concretes. The radiation protection performance of unsaturated polyester resin thus improves with the insertion of BiClO as filler.Öğe Physical, structural, and radiation shielding properties of B 2 O 3 –MgO–K 2 O–Sm 2 O 3 glass network modified with TeO 2(Elsevier Ltd, 2019) Divina, R.; Marimuthu, K.; Sayyed, M.I.; Tekin, H.O.; Ağar, OsmanA new series of Sm 3+ doped Telluroborate glasses with varying TeO 2 content have been prepared following the melt quenching technique. The physical properties like density, refractive index, average molecular weight, molar volume, optical dielectric constant, and metallization criterion were calculated. Structural properties like boron-boron separation (<d B–B >), molar volume of oxygen (V o ), oxygen packing density (OPD), average coordination number (m), bond density (n b ), Poisson ratio (µ cal ), optical electronegativity (? opt ), basicity (? th ), two photon absorption (TPA) coefficient (?), ionic character (I c ), and covalent character (C c ) were calculated. In addition to that, optical bandgap and urbach energy (?E) values of the titled glasses have been calculated from Tauc's plot using the absorption spectra. It is observed that boron-boron separation (<d B–B >) and OPD increases with the decrease in molar volume of oxygen (V o ). Also, the increasing density and refractive index values with the progressive decrease of molar volume with increasing TeO 2 content implies the formation of bridging oxygen (BO) along with nonbridging oxygen (NBO), which is later proved by the Poisson ratio values and basicity values. Further, ionic nature of the Sm 3+ doped telluroborate glasses are identified from the measured optical basicity (? th ), covalent, and ionic characteristic factors. The observed variations in the optical electronegativity, basicity, metallization criterion, and optical bandgap energy (E g ) values have been discussed in terms of the structural changes that take place due to the addition of TeO 2 into the B 2 O 3 network. The gamma photon shielding properties for the prepared samples were studied using MCNPX code in the energy range of 0.356–1.33 MeV. The obtained mass attenuation coefficient exhibit an increasing trend as the TeO 2 content vary from 0 to 40 mol%, especially at the energy 0.356 MeV. Of all the glasses, 4TBS glass sample shows lowest half-value layer value. The study confirms that the replacement of B 2 O 3 by TeO 2 enhances the capability of the prepared glass samples to reduce the gamma photons.Öğe Physical, structural, optical and gamma radiation shielding properties of borate glasses containing heavy metals (Bi 2 O 3 /MoO 3 )(Elsevier B.V., 2019) Sayyed, M.I.; Kaky, K.M.; Gaikwad, D.K.; Ağar, Osman; Gawai, U.P.; Baki, S.O.In an attempt to develop a novel gamma radiation shielding glasses, we prepared borate glasses contains a high concentration of heavy metals like Bi 2 O 3 and MoO 3 with the composition of 20MoO 3 -(80-x)B 2 O 3 -xBi 2 O 3 , were x varied from 30 to 45 mol% using tradition melt-quenching-annealing method. A structural investigation such as XRD and FTIR were characterized to confirm the amorphous structure of the prepared glasses and prove the availability of all chemicals included in these compositions after the melting process. Furthermore, optical studies on these glasses were investigated to prove the transparency of the fabricated glasses. Attenuation characteristics (mass attenuation coefficients, radiation protection efficiency, and half value layer) of the prepared glasses with respect to gamma photons (in the range of 0.356–1.33 MeV) were investigated. The mass attenuation coefficients and radiation protection efficiency results increased with increasing the Bi 2 O 3 content and this improves the attenuation ability for the prepared samples. The radiation protection efficiency also revealed that the glasses have the maximum capability in attenuation gamma photons at 0.356 MeV. The mean free path with the prepared glasses was compared with some concretes which is reported in the literature and with some commercial glasses to assess their potential for use in gamma radiation shielding products.Öğe Shielding behaviour of (20 + x) Bi2O3 – 20BaO–10Na2O–10MgO–(40-x) B2O3: An experimental and Monte Carlo study(Elsevier B.V., 2020) Sayyed, M.I.; Ağar, Osman; Kumar, A.; Tekin, H.O.; Gaikwad, D.K.; Obaid, S.S.In this study, (20 + x) Bi2O3 – 20BaO – 10Na2O – 10MgO – (40-x) B2O3 (where x = 0, 5, 10, 15 and 20 mol%) are fabricated by the melt quenching method. The various radiation shielding parameters for the present glasses are determined experimentally using the gamma spectrometric system and Monte Carlo N-Particle Transport Code System-extended (MCNPX). The mass attenuation coefficient and the effective atomic number are found to be dependent on the photon energy, the glass composition and the concentration of Bi2O3. The results reveal that Bi40B20 sample with the maximum amount of Bi2O3 has the lowest MFP and HVL values among all the other samples as well as the other standard shielding glasses. The radiation shielding efficiency also is calculated and the result shows that the present glass samples can highly attenuate low energetic gamma photons, while the capability to attenuate the incident photons is minimized with increasing the photon energy.Öğe Simulation of shielding parameters for TeO 2 -WO 3 -GeO 2 glasses using FLUKA code(Elsevier B.V., 2019) Sharma, A.; Sayyed, M.I.; Ağar, Osman; Tekin, H.O.This paper aimed to report the results on the investigation of photon attenuation parameters for TeO 2 -WO 3 -GeO 2 glasses using FLUKA Monte Carlo code. In order to test the validity of the present code, the computational values of mass attenuation coefficients have been in confirmation with those of both previously published experimental data (MoO 3 -B 2 O 3 -Bi 2 O 3 ) and XCOM database at various energies between 356 and 1330 keV. The relative deviation between FLUKA and experimental data is below 5.19% while the difference between the present code and XCOM database is found to be almost 2%. Therefore, the estimated results are in good agreement to each other and exhibited that FLUKA simulation is an alternative technique in determining the shielding performance of the present glass system. Additionally, mean free path and half-value layer results were calculated and it was concluded that among the selected glasses, TeWGe5 sample has superior shielding effectiveness.
