Yayınlar
- MakaleAçık Erişim2023Scopus SJRQ1A comprehensive study on structural properties, photon and particle attenuation competence of CoNiFeCr-Ti/Al high entropy alloys (HEAs)
Sakar, Erdem; Guler, Omer; Alım, Bünyamin; Say, Yakup; Dikici, Burak
It is well known that high entropy alloys (HEAs) have a wide range of potential applications as radiation shielding due to their superior properties. The CoNiFeCr-Ti/Al compositions were chosen for their low cost as HEA in this study. The HEAs were successfully produced using the mechanical alloying (MA) method with equimolar CoNiFeCr, CoNiFeCrAl, and CoNiFeCrTi compositions. The production and structural properties of the alloys were investigated in detail. Besides, the photon and particle radiation shielding properties of the HEAs were calculated with the help of Phy-X/PSD, SRIM (10 keV-20 MeV), and ESTAR (10 keV-20 MeV) programs. The photon-matter interaction parameters were calculated in both specific photon energies emitted from 241Am, 133Ba, 109Cd, 60Co, 137Cs, 131I, and 22Na nuclides and a continuous energy range of 15 keV-15 MeV. The characterization of the alloys was investigated by using X-ray diffraction (XRD) and scanning electron microscopes (SEM) attached to an energy dispersive spectroscopy (EDX). It was found that the HEAs have a highly amorphous structure due to the selected production method. The crystal size of the alloys was calculated as 70, 35, and 20 nm for CoNiFeCr, CoNiFeCrAl, and CoNiFeCrTi, respectively. In terms of shielding properties, it has been determined that the produced HEAs have better shielding characteristics for photon and particle radiations than standard shielding concretes. In addition, the results demonstrated that CoNiFeCr alloy, which has the best shielding ability among the HEA alloys, can be used as a shielding material application requiring photon, electron, proton, alpha, and neutron radiations.
AtıfScopus30WoS32OpenAlex32İncele
- MakaleAçık Erişim2023Scopus SJRQ1An extensive survey on radiation protection features of novel hafnium iron-borophosphate glasses: Experimental and theoretical study
Şakar, Erdem; Alım, Bünyamin; Ertap, Hüseyin; Karabulut, Mevlut
This study aimed to determine the radiation (photon and particle) attenuation abilities of Hf added iron-borophosphate glasses considered as a candidate host matrix for Pu containing nuclear waste. Experimental absorption parameters were measured using 133Ba radionuclide for photon radiation, and the same parameters were theoretically calculated using Phy-X/PSD. The obtained data were evaluated comparatively for all glasses depending on the Hf and B contents. It has been determined that all of the glasses examined have photon absorption ability at a level that can be a shielding material for nuclear applications. In addition, the interaction cross-sections with particle radiations were computed using SRIM and ESTAR software. When the data obtained are evaluated thoroughly, it can be said that investigated glasses can be used as shielding in areas that require protection from both photon and particle radiation, in addition to being a candidate material for the vitrification of nuclear wastes containing Pu.
AtıfScopus5WoS6OpenAlex8İncele
- MakaleAçık Erişim2023Scopus SJRQ2Determination of the molecular structure and spectroscopic properties of capsaicin
Çınar, Mehmet; Alım, Bünyamin; Alım, Zuhal; Şakar, Erdem
In this study, the ground state molecular structure and spectroscopic features of cis- and trans-forms of capsaicin were investigated using DFT (B3LYP) invoking 6–311++G(d,p) basis set. The optimized geometry of capsaicin was determined for the isolated molecule in a vacuum, and then the vibrational spectra –IR and Raman-were obtained, and the assignments of fundamental vibrational modes were done. By applying the GIAO method, proton and carbon chemical shifts were computed for the gas and solvated phases. Besides using the TD-DFT, the Hirshfeld surface and Molecular Electrostatic Potential surfaces were obtained and evaluated to understand the electronic properties. The Total and partial density of state (TDOS and PDOS) spectra were also examined. All obtained computational results were compared with the previously reported experimental data. A high accuracy was obtained for the ground state geometrical structure, and thus, the vibrational frequencies especially lie on the finger print region are predicted also with a high correlation. Similarly, the optimization of chemical shift values calculated by considering solvent effects with experimental data were found as high R2 values of 0.9953 and 0.9455 for C and H atoms, respectively. This comparison shows that the DFT method precisely predicts capsaicin's molecular and spectroscopic characteristics.
AtıfScopus16WoS16OpenAlex15İncele
- MakaleAçık Erişim2022Scopus SJRQ2Precipitation-hardening stainless steels: Potential use radiation shielding materials
Alım, Bünyamin; Özpolat, Özgür Fırat; Şakar, Erdem; Han, İbrahim; Arslan, İbrahim; Singh, V.P.; Demir, Lütfü
In this study, it was focused on the research of new materials with high attenuation efficiency that can be used as radiation shielding material due to the incapability of conventional materials. In accordance with this purpose, the radiation shielding capabilities of four different precipitation-hardening stainless steels (PH-SSs), which are symbolized 15-5PH, 15-7PH, 17-4PH and 17-7PH, were determined both experimentally and theoretically in a wide range of radiation energy. For experimental measurements, two different detectors (Si(Li) and Na(Tl)) and twenty-three different photon energies (from 22.1 to 1332.5 keV) emitted from seven different radionuclides were used in narrow-beam transmission geometry. Phy-X/PSD software were used for theoretical calculations. The theoretically calculated parameters were determined both in the photon energies emitted by the radionuclides used in the experiment and in the continuous energy range of 0.015–15 MeV. Furthermore, in order to make a remarkable assessment of the integration of PH-SSs to nuclear energy applications, the all results obtained have been compared with the corresponding values of Fe-based steel concretes (steel-scrap (SS) and steel-magnetite (SM)), which are widely used as conventional shield materials in nuclear power plants. Moreover, in order to choose the best material to be used in nuclear applications among the PH-SSs, the results were evaluated comparatively in terms of both the characteristics of the materials and the magnitude of the radiation shielding parameters. Consequently, it was concluded that the material with the best radiation shielding performance among the examined PH-SSs was 15-7PH and the radiation shielding performance ranking was generally in the form of 15-7PH ≥ 15-5PH > 17-4PH > 17-7PH > SM > SS. Due to both high attenuation efficiency and superior properties for radiation shielding, it was determined that the PH-SSs can be used as new shielding materials in nuclear applications.
AtıfScopus25WoS25OpenAlex27İncele
- MakaleAçık Erişim2020Determination of Radiation Protection Features of the Ag2O Doped Boro-Tellurite Glasses Using Phy-X / PSD Software
Alım, Bünyamin
This study focused on the radiation protection features of the Ag2O doped boro-tellurite glass samples in the form of (x)Ag2O/(100-x)(65B2O3-35TeO2) where x=10, 15, 20, 25 and 30 mol%. by using Phy-X / PSD software, the radiation protection parameters such as mass attenuation coefficient (MAC), linear attenuation coefficient (LAC), half-value layer (HVL), mean free path (MFP), total atomic and electronic cross-sections (ACS and ECS), effective atomic number (Zeff) , effective electron density (Neff) and effective conductivity (σeff) of present glasses were calculated in the photon energy range of 0.015-15 MeV. In order to evaluation the usability of these glasses in terms of radiation protection, the all investigated protection parameters were also calculated for commercial RS 253 glass and some concretes such as ordinary concrete (OC), hematite-serpenite (HS) and basalt-magnetite (BM) that are commonly used as shielding material in the nuclear application. The results obtained were evaluated in terms of both photon energy and chemical composition of the glasses examined. Additionally, the results obtained for the examined glasses were compared with the corresponding values obtained for the comparison materials presented to determine the best radiation protection glass. It was clearly observed that the MAC, LAC, ACS, ECS and Zeff values increased with the increasing of molar doping percentage Ag2O in the glasses. It was found that the radiation protection capacities of the Ag2O doped boro-tellurite glasses is found higher than the other compared materials. Maximum MAC, LAC, ACS, ECS and Zeff values were observed in the sample of G5 that contains 30% Ag2O. This study indicates that the disilver oxide doped tellurite glasses can be developed as radiation protection materials for many nuclear applications.
AtıfOpenAlex26TR Dizin6
İncele - MakaleAçık Erişim2020Scopus SJRQ2Phy-X / PSD: Development of a user friendly online software for calculation of parameters relevant to radiation shielding and dosimetry
Şakar, Erdem; Özpolat, Özgür Fırat; Alım, Bünyamin; Sayyed, M.I.; Kurudirek, Murat
A user friendly online Photon Shielding and Dosimetry (PSD) software available at https://phy-x.net/PSD has been developed for calculation of parameters relevant to shielding and dosimetry. These parameters include linear and mass attenuation coefficients (LAC, MAC), half and tenth value layers (HVL, TVL), mean free path (MFP), effective atomic number and electron density (Zeff, Neff), effective conductivity (Ceff) energy absorption and exposure buildup factors (EABF, EBF). The software can generate data on shielding parameters in the continuous energy region (1 keV-100 GeV). Also, some well-known radioactive sources (22Na, 55Fe, 60Co, 109Cd, 131I, 133Ba, 137Cs, 152Eu and 241Am) along with their energies and some characteristic (K-shell) X-ray energies of Cu, Rb, Mo, Ag, Ba and Tb elements are available in the software and can be selected by the user. Thus, one can obtain the shielding parameters at photon energies available for the predefined energies. Moreover, another parameter relevant to shielding i.e. the fast neutron removal cross section (FNRCS) can be calculated for a compound or a mixture using this software. The software is freely available online after having registered to the Phy-X platform.
AtıfScopus2019WoS1977OpenAlex2133İncele
- MakaleAçık Erişim2020Scopus SJRQ2Experimental investigation of radiation shielding performances of some important AISI-coded stainless steels: Part I
Alım, Bünyamin; Şakar, E.; Baltakesmez, Ali; Han, İbrahim; Sayyed, M.I.; Demir, Lütfü
The investigation of radiation shielding performances of AISI-302, 304, 321 and 430 stainless steels which have wide range of application because of their superior mechanical properties, temperature and corrosion resistances was aimed in this study. In accordance with this purpose, photon-shielding parameters of these stainless steels were calculated both experimentally and theoretically. These parameters calculated are linear attenuation coefficient, mass attenuation coefficient, mean free path, half-value layer, quarter-value layer, tenth-value layer, total atomic cross-section, total electronic cross-section, effective atomic number, effective electron number and effective conductivity. They were experimentally measured at twenty-three different energies in the range 22 keV and 1333 keV. The photon energies were obtained from seven different radioactive sources (22Na, 60Co, 241Am, 109Cd, 137Cs, 152Eu and 133Ba). The Si(Li) and NaI(Tl) detectors were separately used taking into account of energy-efficient regions to counting process at narrow-beam transmission geometry. In addition, all these parameters were computed at the 15 keV‒15 MeV wide energy range, theoretically. In order to make a satisfying assessment about radiation shielding capabilities of AISI 302, 304, 321 and 430 alloys, all calculations were also made for ordinary, steel-scrap and steel-magnetite concretes (Fe-based steel concretes) that are most commonly used as shielding material in many nuclear applications. According to the results obtained, it was observed that the radiation shielding performances of AISI 300 austenitic stainless steel series with containing Ni are superior to that of both AISI 430 ferritic stainless steel and examined concretes.
AtıfScopus52WoS46OpenAlex57İncele
- MakaleAçık Erişim2020Scopus SJRQ2A comprehensive study on radiation shielding characteristics of Tin-Silver, Manganin-R, Hastelloy-B, Hastelloy-X and Dilver-P alloys
Alım, Bünyamin
In this study, it is aimed to investigate alloys that can replace lead and its derivatives in terms of radiation shielding. A new alternative shielding material must have optimum properties that should be present in a protective material. For this purpose, this study focused on the determination of the radiation-shielding characteristics of five different alloys named Tin-Silver, Manganin-R, Hastelloy-B, Hastelloy-X and Dilver-P. The photon interaction parameters (µ, µm, λ, X1/2, σT, σe, Zeff, Neff, σeff and RPE) that give significant information about the radiation shielding capacities of the materials were calculated for the alloys in the energy range from 30 to 1333 keV. The narrow-beam transmission geometry was used to determine these parameters accurately and was adjusted such that the error rate is minimized. The present samples were irradiated with photons of nineteen different photon energies emitted from seven different radionuclides (241Am, 133Ba, 109Cd, 152Eu, 22Na, 137Cs and 60Co). Photon intensities were measured by using two different detectors (Si(Li) and NaI(Tl)) for convenient photon energy regions. Then, these parameters were also calculated theoretically using Phy-X/PSD software in order to compare the experimental and theoretical results. Furthermore, the Rinc/total, Zeq, G-P fitting coefficients (a, b, c, d and XK) and exposure build-up factors (β) for the alloys were calculated using Phy-X/PSD software at photon energy range from 0.015 to 15 MeV. In order to make a significant comparison about the shielding capacities of investigated alloys, the µm values obtained for the alloys were compared with corresponding values of Pb metal, RS 253 glass and Cupero-Nickel alloy. Consequently, the descending order of MAC values in the all surveyed energy region was obtained as Tin-Silver > Manganin-R > Hastelloy-B > Hastelloy-X > Dilver-P. In the low energy region, it was found that the all present alloys have better shielding performances than RS 253 glass and Cupero-Nickel alloy. The experimental results also revealed that the Tin-Silver alloy has 25% better shielding performance than Pb metal in the energy range of 30–88 keV. Finally, it was concluded that Manganin-R alloy could be considered as the most ideal shielding material in the entire photon energies studied along with its other superior features (high density (10.22 g cm−3), high melting point (2500–2600 °C), high tensile strength (560–1150 MPa), high modulus of elasticity (320 GPa) and high specific heat (305 J K−1 kg−1) although the Tin-Silver alloy had the highest µm values among the examined alloys.
AtıfScopus57WoS49OpenAlex58İncele
- MakaleAçık Erişim2020Scopus SJRQ2Evaluation the gamma, charged particle and fast neutron shielding performances of some important AISI-coded stainless steels: Part II
Alım, Bünyamin; Şakar, Erdem; Han, İbrahim; Sayyed, M.I.
This is the second part of a two-part study on the investigation of radiation shielding performances of some important AISI-coded stainless steels (AISI-302, 304, 321 and 430). Part 1 addressed experimental evaluation by means of measured photon-material interaction parameters. In this second part, we focused on the calculation and discussion of other interaction parameters, which are a guide to choice optimum shielding materials in the nuclear processes for the present AISI-coded stainless steels. The present stainless steels have superior mechanical properties, high temperature and corrosion resistances and these properties can make them favorite materials for nuclear applications. For this reason, firstly, the incoherent scattering/total attenuation ratio (Rinc/total) and equivalent atomic number (Zeq) were calculated in the energy region of 0.015–15 MeV. Secondly, the exposure build-up factor (EBF) and energy absorption build-up factor (EABF) were determined to select steels by using Geometric Progression (G-P) fitting method, which have five parameters (a, b, c, d and XK coefficients), up to penetration depth of 40 MFP at energy 0.015–15 MeV. Thirdly, the mass stopping powers (MSPs; dE/ρdx; MeVcm2/g) and ranges (Re, Rp and Rα; μm) for electron, proton and alpha particle interactions were calculated at energy 10 keV-20 MeV. Finally, the fast neutron removal cross-sections (FNRCSs; ∑R; cm−1) were calculated. To be able to make comparison and a satisfying assessment about radiation shielding capabilities of present AISI-coded steels, all parameters were also computed for ordinary (OC), steel-scrap (SS) and steel-magnetite (SM) concretes (Fe-based steel concretes) that are most commonly used as a shielding material in many nuclear applications. The shielding capabilities of the present stainless steels against both gamma and the fast neutron and charged particle radiation were evaluated in the light of the calculated parameters. As a result of the mutual evaluation of the results obtained for the shielding concretes and the examined stainless steels, it was found that present stainless steels had excellent shielding properties compared to shielding concretes in terms of both photon radiation and particle radiation.
AtıfScopus38WoS35İncele
- MakaleYalnız künye2019Scopus SJRQ2Leaded brass alloys for gamma-ray shielding applications
Şakar, Erdem; Büyükyıldız, Mehmet; Alım, Bünyamin; Şakar, Betül Ceviz; Kurudirek, Murat
The leaded brasses show high machinability and atmospheric corrosion resistance. Hence, they are being used in different applications such as machine parts, valves, fittings etc. Besides, they can serve as radiation shields as they contain lead and their radiation shielding properties were not investigated so far. Thus, the aim of this study is to determine the radiation shielding properties of leaded brasses. Standard (CuZn) and leaded (CuZnPb) brasses were prepared and their mass attenuation coefficients (μ/ρ), half-value layers (HVL), tenth-value layers (TVL), mean free paths (MFP) and effective atomic numbers (Z eff ) were determined. Linear attenuation coefficients (μ) of the alloys were measured first at 53, 276, 302, 356 and 383 keV using a HPGe detector and a 133 Ba radioactive source. These values were then used to obtain other parameters. A good agreement was observed between experimental and theoretical results for HVL, TVL and MFP (Dif. ≤ 9%). Photon buildup through the present materials was studied in terms of exposure buildup factor (EBF). Results were presented and discussed regarding the photon energy and penetration depths. Fast neutron removal cross sections were also calculated for the given alloys. Some alloys were also evaluated morphologically by using EDX mapping. The leaded brasses were compared with standard shielding concretes and superior shielding properties against gammas and fast neutrons were obtained when compared with concretes.
AtıfScopus114WoS108OpenAlex128İncele
- MakaleYalnız künye2019Scopus SJRQ2The relationship between the external magnetic field and K X-ray intensity ratios of immiscible MoxAg1-x alloys
Uğurlu, Mine; Alım, Bünyamin; Demir, Lütfü
Kβ/Kα intensity ratios were obtained for Molybdenum-Silver alloys produced in different concentration range in different magnetic fields. It was seen that these values without magnetic field were found slight different from each other for pure Mo, pure Ag, alloyed Mo and alloyed Ag. It was determined that Kβ/Kα intensity ratios change slightly by depending on alloying element composition and it was seen that Kβ/Kα intensity ratios of Mo and Ag are in the range of the literature valuesFurthermore, that these values have same direction with the changing of the magnetic field for all alloying composition may take us conclusion which alloys in different concentration may have same magnetic properties.
AtıfScopus3WoS2OpenAlex4İncele
- MakaleAçık Erişim2017Scopus SJRQ2L-shell differential cross-section and alignment of uranium at 59.54-keV photon energy
Akkuş, Tuba; Alım, Bünyamin; Yılmaz, Demet; Şahin, Yusuf
L X-ray differential cross-sections of uranium were calculated at several polar scattering angles (85°, 95°, 105°, 115°, 125°, and 135°) at 59.54-keV photon energy by using a Si(Li) detector. We observed that Ll and Lα X-rays were dependent on the polar scattering angle, whereas Lβ and Lγ X-rays were independent of the polar scattering angle. Therefore, the anisotropy parameters for Ll and Lα X-rays were obtained using the intensity ratios of Ll to Lγ X-rays and of Lα to Lγ X-rays to reduce some systematic errors.
AtıfScopus2WoS2OpenAlex2İncele
- MakaleAçık Erişim2017Scopus SJRQ1Delocalization and charge transfer studies of PERMENDUR49, KOVAR and Ti50Co50 alloys from relative K X-ray intensity ratios
Uğurlu, Mine; Alım, Bünyamin; Han, İbrahim; Demir, Lütfü
Kβ-to-Kα X-ray intensity ratios of Fe, Ni, Co, Ti, V in pure form and PERMENDUR49 (Fe49Co49V2), KOVAR (Fe54Ni29Co17) and Ti50Co50 alloys were calculated in order to determine valence-electron structure of the samples. The obtained experimental Kβ-to-Kα X-ray intensity ratios were found to be 0.1252 ± 0.0025, 0.1256 ± 0.0027, 0.1298 ± 0.0026, 0.1327 ± 0.0028, 0.1346 ± 0.0027 for pure Ti, V, Fe, Co and Ni, respectively. These values of present pure metals have increased with the increment in atomic number of these pure metals. Also, although the obtained these values for metal atoms in PERMENDUR49, Ti50Co50 and for Fe, Ni metal atoms in KOVAR approximately compatible with respect to results same pure metals, the obtained experimental Kβ-to-Kα X-ray intensity ratios for Co in KOVAR are significantly different from the appropriate values for pure Co metal. Then, the valence-electron populations of these alloys were calculated in order to answer as to why the characteristic properties of the studied alloys are distinct from each other. The valence-electron structures of these metals in pure form and alloys were determined by comparison of the calculated Kβ-to-Kα X-ray intensity ratios with the results of multi-configurations Dirac-Fock (MCDF) calculations to understand the charge-transfer and/or delocalization phenomena of these alloys. The experimental n3d values were found to be 3.2694, 4.7905, 7.7941, 7.9618, 8.500 for pure Ti, V, Fe, Co and Ni, respectively. The calculated 3d and 4s, 4p electron population values for Ti, V and Co in pure form have shown very little deviation from the appropriate values of Ti in Ti50Co50 and Co, V in PERMENDUR49. Also, the deviation for these values is greater for Fe, Ni, in KOVAR, Co in Ti50Co50, Fe in PERMENDUR49 with respect to the corresponding values of pure metals and the largest deviation for these values is observed for Co metal atoms in KOVAR alloy. We have also calculated the weighted average numbers of 3d and 4s, 4p electrons per one atom as well as the superposition of 3d and 4s, 4p electrons, as obtained from pure metal values. While the obtained superposition 3d electron numbers of present alloys exhibit a decreasing tendency as S3d(Ti50Co50) < S3d(PERMENDUR49) < S3d(KOVAR), the obtained weighted average 3d electron numbers of present alloys has opposite tendency (A3d(KOVAR) < A3d(PERMENDUR49) < A3d(Ti50Co50)). The analysis show that valance-electron population of elements in these alloys indicated differences with respect to the pure metal and each other. These differences can be related to type of alloy elements, concentration of alloy elements, charge transfer and/or delocalization phenomena between of individual metal atoms in alloys. Also, the obtained results show that there are alloying effect on valence-electron population due to charge transfer and/or delocalization phenomena.
AtıfScopus15WoS15OpenAlex16İncele
- MakaleAçık Erişim2016Scopus SJRQ2Effect of external magnetic field on the Kβ/Kα X-ray intensity ratios of TixNi1-x alloys excited by 59.54 and 22.69 keV photons
Perişanoğlu, Ufuk; Alım, Bünyamin; Uğurlu, Mine; Demir, Lütfü
The effects of external magnetic field and exciting photon energies on the Kβ/Kα X-ray intensity ratios of various alloy compositions of Ti-Ni transition metal alloys have been investigated in this work using X-ray fluorescence spectroscopy. The spectrum of characteristic K-X-ray photons from pure Ti, pure Ni and TixNi1-x (x=0.30; 0.40; 0.50; 0.60; 0.70) alloys were detected with a high resolution Si (Li) solid-state detector. Firstly, Kβ/Kα X-ray intensity ratios of pure Ti, pure Ni and TixNi1-x alloys were measured following excitation by 59.54 keV γ-rays from a 200 mCi 241Am radioactive point source without any magnetic field and under 0.5 and 1 T external magnetic fields, separately. Later, the same measurements were repeated under the same experimental conditions for 22.69 keV X-rays from a 370 MBq109Cd radioactive point source. The results obtained for Kβ/Kα X-ray intensity ratios of pure Ti, pure Ni, Ti and Ni in various Ti-Ni alloys were evaluated in terms of both external magnetic field effect and exciting photon energy effect. When the results obtained for both exciting photon energies are evaluated in terms of changing of Kβ/Kα X-ray intensity ratios depending on the alloy composition, the tendency of these changes are observed to be similar. Also, Kβ/Kα X-ray intensity ratios for all samples examined have changed with increasing external magnetic field. Therefore, the results obtained have shown that Kβ/Kα X-ray intensity ratios of Ti and Ni in TixNi1−x alloys are connected with the external magnetic field. The present study makes it possible to perform reliable interpretation of experimental Kβ/Kα X-ray intensity ratios for Ti, Ni and TixNi1−x alloys and can also provide quantitative information about the changes of the Kβ/Kα X-ray intensity ratios of these metals with alloy composition.
AtıfScopus32WoS31OpenAlex32İncele
