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A Comprehensive Research on Gamma-Ray Attenuation Characteristics of The Metal-Doped Hap and Natural Animal Bone
(2020) Köksal, Oğuz Kağan; Cengiz, Erhan; Tozar, Ali; Karahan, İsmail Hakki; Apaydın, Gökhan
This investigation focuses on the gamma ray attenuation parameters of natural animal bone, iron, cobalt, copper andzinc doped Nano hydroxyapatite artificial bone powders and pure hydroxyapatite. The present specimens were excitedby means of gamma ray photons with 59.5 keV energy radiated from a 241-Amercium annular radioactive source with50 mCi activity by means of narrow beam transmission geometry. The transmitted gamma-rays were counted withusing Ultra Low Energy Germanium (Ultra-LEGe) detector with a resolution 150 eV at 5.95 keV. The gamma-rayattenuation characteristics such as mass attenuation coefficient (MAC) (µ/?), linear attenuation coefficient (LAC) (µ),half value layer (HVL), tenth value layer (TVL) and mean free path (MFP), which has a significant role in theattenuation studies, are also calculated. The values obtained were checked with the predicted values from the XCOMNIST. The results show that the attenuation data of the metal-doped hydroxyapatite synthetic bone dust is very close tothe value of the natural animal bone.
A research on the gamma ray attenuation characteristics for real bone and manganese substituted artificial bone dust
(2020) Köksal, Oğuz Kağan; Tozar, Ali; Cengiz, Erhan; Karahan, İsmail Hakki; Apaydın, Gökhan
This research focalized on the gamma ray attenuation charesteristics of real bone andHistory:manganese substituted Nano hydroxyapatite artificial bone dusts. The current samples wereReceived:24.03.2019excited with using 59.5 keV photons emitted from an 241Am annular radioisotope source withAccepted:29.01.202050 mCi activity by using a narrow beam transmission geometry and detected with using UltraKeywords:Low Energy Germanium detector with a resolution 150 eV at 5,95 keV experimentally. TheAttenuationgamma-ray attenuation parameters such as linear attenuation coefficient, half value layer, tenthcharesteristics, Mnvalue layer and mean free path are also calculated experimentally and theoretically. Thesubstituted artificialpresent results points out that the attenuation values of the manganese substitutedbone dust, Real bone,hydroxyapatite artificial bone dust is very close to the value of the real bone.Transmission
An investigation of gamma ray mass attenuation from 80.1 to 834.86 keV for fabric coating pastes used in textile sector
(Springer Singapore Pte Ltd, 2020) Erenler, Alev; Bayram, Tuncay; Demirel, Yusuf; Cengiz, Erhan; Bayrak, Rıza
In the present study, we investigate several textile coating pastes used in the market based on their radiation protection capability for gamma rays. The gamma ray mass absorption coefficients of some coating pastes doped with antimony, boron and silver elements have been investigated. It has been determined that the gamma ray mass attenuation coefficient decreases rapidly as the energy of the gamma rays increases. It was determined that the doping of the main printing paste with silver and antimony considerably increased the gamma ray absorption capability of main paste. However, the doping of the paste with boron reduces the mass absorption of gamma rays. In particular, the gamma ray mass absorption power of the main paste doped with silver and antimony was determined to be useful in the gamma energy range from 80 to 140 keV. This indicates that the newly doped textile material may be considered for radiation protection in the case of low-energy gamma rays .
Analysis the Metal Composition of Fish Samples Collected From Karacaören II Dam Lake
(2024) Köksal, Oğuz Kağan; Apaydın, Gökhan; Cengiz, Erhan; Sirin, Murat; Baltaş, Hasan; Çakmak, Eyüp; Tirasoglu, Engin
The objective of this study was to analyze the metal content in the organs of Oncorhynchus mykiss, commonly known as rainbow trout, at 12 different locations within the cages located in Karacaören II Dam Lake. The metal contents in fish samples were analyzed using a PANalytical Epsilon5 energy dispersive X-ray fluorescence (EDXRF) spectrometer. We will analyze the findings by displaying the fluctuating metal concentrations in various internal organs over the seasons.
Assessment of natural radioactivity and radiological risk of sediment samples in Karacaören II dam Lake, Isparta/Turkey
(Alanya Alaaddin Keykubat Üniversitesi, 2019) Apaydın, Gökhan; Köksal, Oğuz Kağan; Cengiz, Erhan; Tıraşoğlu, Engin; Baltaş, Hasan; Karabulut, Kazım; Söğüt, Ömer
This research aimedto assess natural radioactivity levels in lake sediment of Karacaören II Dam.In this study sediment samples were collected from 12 station of lake in May,2016. The natural radionuclides 226Ra, 232Th and 40K were measured with a coaxialHPGe detector (Canberra, GC 1519 model) of 15% relative efficiency and aresolution of 1.9 keV at the 1332 keV gamma of 60Co. In order to assess the radiological hazards resulting from naturalradioactivity, radium equivalent activities (Raeq), absorber dose rate (D), internal (Hin)and external (Hex) hazard index,annual effective dose rate (AED) andExcess life time cancer risk (ELCR)were calculated and compared with recommended values of internationalorganizations.
Assessment of the mass attenuation parameters with using gamma-rays for manganese substituted nano hydroxyapatite
(Pergamon-Elsevier Science Ltd, 2019) Köksal, Oğuz Kağan; Apaydın, Gökhan; Tozar, Ali; Karahan, İsmail Hakkı; Cengiz, Erhan
Manganese substituted hydroxyapatite nanoparticles (nMnHAp) were produced using the ultrasonic wet chemical method. The elemental analysis was performed using Scanning Electron Microscopy (SEM) with integrated Energy Dispersive X-ray Spectrometry (EDX). The mass attenuation coefficients of manganese substituted hydroxyapatite nanoparticles have been measured at 59.5 keV gamma energy emitted from Am-241 radioisotope annular source with 50 mCi activity by using Ultra Low Energy Germanium Detector. These values are found to be in good agreement with theoretical values based on calculated XCOM data. Electron densities and effective atomic numbers were calculated by using the mass attenuation coefficients. Also, the mass attenuation coefficient of the real bone was determined as experimentally. The obtained results may provide information on how much radiation is transmitted through the sample when they are exposed to gamma-rays at 59.5 keV by comparing real bone.
Determination of L-shell fluorescence parameters of thallium in thallium compounds
(Taylor & Francis Inc, 2021) Cengiz, Erhan; Tirasoglu, Engin; Apaydin, Gokhan; Koksal, Oguz Kagan
The L-i (i = l, alpha, beta, and gamma) production cross-sections, L-shell average fluorescence yields, and Coster-Kronig vacancy transfer factors for L-3 subshell X-rays of thallium in some thallium compounds were determined using Energy Dispersive X-ray Fluorescence spectrometer. The compounds were excited by 59.5 keV gamma-rays from an Americium-241 annular radioactive source, and the L X-rays emitted by the compounds were counted using an ultra-low energy germanium detector with a resolution of 150 eV at 5.9 keV. The production cross-sections, average fluorescence yields, and Coster-Kronig vacancy transfer factors of thallium in these compounds were compared with theoretical calculations and available experimental values of the pure thallium.
Determination of valence electronic structure of Ni in Ni-B alloy coatings using K-beta-to-K-alpha X-ray intensity ratios
(Pergamon-Elsevier Science Ltd, 2019) Cengiz, Erhan; Köksal, Oğuz Kağan; Apaydın, Gökhan; Karahan, İsmail Hakkı; Ünal, Ersin
In this study, K-beta-to-K-alpha X-ray intensity ratios of Ni in Ni-B alloy coatings were investigated. These samples were excited by 59.5 keV gamma-rays from a Am-241 annular radioactive source. K X-rays emitted by the samples were counted using an Ultra-LEGe detector with a resolution of 150 eV at 5.9 keV. The K-beta-to-K-alpha X-ray intensity ratios of Ni-B alloys are compared with pure Ni and each other. Deviations between the results were explained by the change in valence electronic structures of Ni in Ni-B alloy coatings.
Elemental analysis for iron, cobalt, copper and zinc decorated hydroxyapatite synthetic bone dusts by EDXRF and SEM
(Elsevier Science Bv, 2019) Köksal, Oğuz Kağan; Wrobel, Pabel; Apaydın, Gökhan; Cengiz, Erhan; Lankosz, Marek; Tozar, Ali; Özkalayci, Fatih
Iron, cobalt, copper and zinc decorated hydroxyapatite nanoparticles were produced with using ultrasonically assisted wet chemical method. Calcium nitrate tetra hydrate and dibasic ammonium phosphate were used as calcium and phosphorous source, respectively. Calcium nitrate tetra hydrate and dibasic ammonium phosphate solutions were prepared by dissolving the salts in distilled water and at different concentrations of decorated elements (iron, cobalt, copper and zinc) were appended to the calcium nitrate tetra hydrate solution. Stoichiometric decorated hydroxyapatite nanoparticles were analysed by energy dispersive X-ray fluorescence (EDXRF) with using standard method and the element analysis was determined with looking at the grain structures by Energy Dispersive X-Ray (EDX) and scanning electron microscopy (SEM). Not only have the concentrations of decorated metals but also calcium and phosphorus ratio for artificial bone powders been determined. As a result, calcium and phosphor ratio and metal decorated contents were evaluated according to the production values and compared previous studies. The answer to the question of how much of the contribution amounts was searched.
Evaluation of ecological risk, source, and spatial distribution of some heavy metals in marine sediments in the Middle and Eastern Black Sea region, Turkey
(2022) Apaydın, Aylin; Kabaoğlu, Hatice; Apaydın, Gökhan; Şirin, Murat; Cengiz, Erhan; Köksal, Oğuz Kağan; Baltaş, Hasan; Tıraşoğlu, Engin
In the present study, the concentration levels of heavy metals such as Mn, Fe, Ni, Cu, Zn, Cr, and Pb in sediment samples collected from 16 sampling locations in the Middle and Eastern Black Sea regions, Turkey, were measured using energy dispersive X-ray fluorescence spectroscopy (EDXRF). Various pollution parameters and methods, such as the enrichment factor (EF), geo-accumulation index (Igeo), contamination factor (CF), pollution load index (PLI), ecological risk index (RI), and geo-spatial distribution patterns, were used to assess the pollution status, ecological risks, and sources of metals in sediment in detail. The mean concentrations of Mn, Fe, Ni, Cu, Zn, Cr, and Pb were found to be 565.38, 46,000, 34.38, 104.06, 109.88, 87.31, and 32.31 mg/kg, respectively. Results showed that the mean concentrations of Cu, Zn, and Pb exceeded the crustal shale value, with the exception of Mn, Fe, Ni, and Cr. According to the calculated pollution parameters, although minimal or moderate pollution was detected in the area investigated, it was determined that there was a very low ecological risk. Multivariate statistical analysis results showed that Cu, Zn, and Pb levels in the investigated region were slightly influenced by anthropogenic inputs such as mining and agricultural practices. In addition, the geo-spatial distributions of Cu, Zn, Fe, and Pb were found to be higher in this region due to the mining activities carried out in the Eastern Black Sea region.
Examination of polymeric azomethine compounds and their transition metal complexes by using XRF and XRD technique
(Office Spectroscopy & Spectral Analysis, 2020) Söğüt, Ömer; Kara, Betül Demirezen; Apaydın, Gökhan; Cengiz, Erhan; Kazancı, Ayşe
In this study, the electronic transition properties and structural analysis of the metal complexes (Ni (II), Co(II), Cu( II) and Mn( II)) of three different polymer ligands were performed by using XRF and X-ray diffraction (XRD) techniques, respectively. The structural analysis of the polymers and their complexes were performed by XRD technique and some of the polymers were found to be in the face-centred cubic (fcc) structure. In addition, the values of the present K X-ray intensity ratios are significantly greater than the values reported in literature.
Examination of the change of the characteristic X-rays of the Zinc in fluorine- and boron-doped ZnO thin films
(Polish Acad Sciences Inst Physics, 2018) Söğüt, Ömer; Kerli, Süleyman; Cengiz, Erhan; Apaydın, Gökhan
In this study, K-beta / K-alpha X-ray intensity ratios of zinc in pure zinc, undoped ZnO thin film and boron and fluorine-doped ZnO thin films have been investigated. These samples have been excited by 59.5 keV gamma-rays from a Am-241 annular radioactive source. K X-rays emitted by the samples have been counted using an Ultra-LEGe detector with a resolution of 150 eV at 5.9 keV. The K-beta / K-alpha X-ray intensity ratios of the doped ZnO thin films have been compared with that of the undoped ZnO thin film. The deviations between the results can be explained by delocalization and/or charge transfer phenomena causing change in valence electronic configuration of zinc.
Exploration of Seasonal Metal Pollution in Karacaören II Dam Lake Sediment Samples using X-ray Fluorescence Method
(2023) Apaydın, Gökhan; Köksal, Oğuz Kağan; Cengiz, Erhan; Sirin, Murat; Baltaş, Hasan; Tirasoglu, Engin
In this study, the seasonal metal pollution of sediment samples taken from twelve distinct notes of the Karacaören II Dam Lake was examined. The quantity of metal in soil samples was determined using energy dispersive X-ray fluorescence spectroscopy. The geoaccumulation index and enrichment factor expressions were created using the metal concentrations found in the sediments. Seasonal values at the local, state, and international levels were compared to the findings. The ratios of the elements copper, zinc, lead, arsenic, nickel, chromium, and mercury, measured in parts per million (ppm), were found to be 42-96, 53-78, 11-14, 4-7, 233-244, and 611-711, respectively. There is also discussion of the sediments' elemental composition and degree of pollution. In contrast, it was found that the Urbach energy increased from 0.246 eV to 0.630 eV with increasing levels of V2O5. These synthetic glasses' densities and molar volumes were also investigated and discussed.
Investigation of mass attenuation coefficients ofcopper-silverthin films at 14.93-48.82keVenergy range
(Wiley, 2020) Söğüt, Ömer; Cengiz, Erhan; Yavuz, Musab
In this study, the mass attenuation coefficients of copper-silver thin-film alloys, produced by the thermal evaporation method at various concentrations, were measured at six different energies in the range of 14.93-48.82 keV (keV) by X-ray Fluorescence technique (XRF). A(241)Americium radioisotope source, having 50 mCi intensity and 59.54 keV energy photons, was used to stimulate the samples, and an Ultra-LEGe detector was used to count the characteristic X-rays emitted from the samples and from the source. At 14.93, 17.44, and 23.10 keV energies, the mass attenuation coefficients of Cu-Ag thin-film alloys increased with increasing Cu concentration, while decreasing with increasing Cu concentration at 27.37, 32.068, and 48.82 keV energies. However, at 14.93, 17.44, and 23.10 keV energies, the mass attenuation coefficients decreased with increasing Ag concentration, while increasing with increasing Ag concentration at 27.37, 32.068, and 48.82 keV energies. The obtained results were compared with the values theoretically predicted by XCOM, and the experimental results are in good agreement with theoretical values within the error limits.
Investigation of radiation shielding properties of CeO2 thin films prepared at different molarities
(Iop Publishing Ltd, 2025) Kanmaz, Imran; Koksal, Oguzkagan; Apaydin, Gokhan; Tomakin, Murat; Cengiz, Erhan
In this study, CeO2 thin films were produced using the spin coting method, which is one of the sol-gel methods, in six different molarities. X-ray diffraction (XRD) patterns revealed the characteristic peaks of the films, while Field Emission Scanning Electron Microscopy (FESEM) confirmed their homogeneous structure. Then, radiation shielding parameters like linear absorption coefficient (LAC), mass absorption coefficient (MAC), tent value layer (TVL), mean free path (MFP), and half value layer (HVL) were thoroughly examined. The results showed that increasing molarity had a significant effect on the thickness values of thin films and the absorption parameters were found to improve with increasing molarity. Both LAC and MAC values decrease as the energy level increases, but the increase in CeO2 molarity leads to a strong increase on these coefficients. The HVL value was also found to be 0.42 cm at the lowest energy of 14.957 keV and to be around 10 cm at the greatest energy of 59.543 keV (0.05 M). When the radiation energy applied to the material was raised from 14.957 keV to 59.543 keV, it was found that the MFP values of 0.05 M CeO2 thin films grew gradually from 0.61 cm to 14.51 cm. High energy radiation of 59.543 keV and a low density (0.05 M) medium resulted in peak TVL values of 33.423 cm, allowing the radiation to pass through the material with minimal interaction.
Investigation on Li (i = l, ?, and ?)–to-L? X-ray Intensity Ratios of Tl in Thallium Compounds
(2019) Cengiz, Erhan
The Li (i = l, ?, and ?)–to-L? X-ray intensity ratios of Tl in some thallium compounds were measured by EDXRF spectrometer. These compounds were excited by 59.5 keV gamma-rays from a 241Am annular radioactive source. L X-rays emitted by the compounds were counted using an Ultra-LEGe detector with a resolution of 150 eV at 5.9 keV. Li –to-L? X-ray intensity ratios of Tl in these compounds are compared with that of the pure Tl calculated theoretically. While the values of Ll/L? and L?/L? intensity ratios are compatible with the theoretically calculated value, the values of L?/L? intensity ratios have differences.
K?-to-K? X-ray intensity ratio studies on changes of valance electron structures of nickel in Ni-B/hBN composite coatings
(Pergamon-Elsevier Science Ltd, 2022) Cengiz, Erhan; Karahan, Ismail Hakki
In this study, K beta/K alpha X-ray intensity ratio values of nickel in Ni coating and Ni-B/hBN (hBN: hexagonal Boron Nitride) composite coatings have been determined by the Energy Dispersive X-ray fluorescence spectroscopy (EDXRF) method. The K beta/K alpha X-ray intensity ratios of nickel in the Ni coating and Ni-B/hBN composite coatings have been compared with theoretical, experimental, and fitted data of the pure nickel. X-ray Diffraction (XRD) and Scanning Electron Microscopy (SEM) measurements have been performed to observe how hBN particles with different bath concentrations affected the crystal structure and microstructure, respectively. The valence electronic structure of Ni in the coatings has been determined by comparing the experimental K beta/K alpha X-ray intensity ratios with Multiconfiguration Dirac-Fock (MCDF) predictions for various electron structures of Ni. The results show that while the values of the K beta/K alpha X-ray intensity ratio of the Ni-B/hBN composite coatings over pure Ni coatings increases, the 3d electron populations decreases. The change in the valence electronic structure were interpreted through charge transfer and rearrangement processes.
Spatiotemporal distribution, source identification and risk assessment of potentially toxic elements in sediments along the Alanya/Antalya coastline, Mediterranean Sea
(Springer, 2025) Cengiz, Erhan; Sirin, Murat; Yesilkanat, Cafer Mert; Apaydin, Gokhan
This study investigates the concentrations of potentially toxic elements (PTEs), ecological risks, and human health effects in sediment samples from 11 points along the Alanya coastline, influenced by industrial, agricultural, and tourism activities. Energy dispersive X-ray fluorescence spectroscopy was used for analysis. The mean concentrations of Mn, Fe, Ni, Cu, Zn, Cr, and As were 281, 14, 30, 34, 66, 60, and 12 mg/kg, respectively. The enrichment factor values were ranked as follows: As (3.94), Zn (2.94), Cu (2.83), Cr (2.45), Ni (1.29), and Mn (1.19), indicating moderate enrichment for Cu, Zn, Cr, and As, and minimal enrichment for Ni and Mn. The geo-accumulation index indicated minimal contamination, supporting the conclusion that Alanya is not heavily impacted by the PTEs studied. The contamination factor values were highest for As (0.90) and lowest for Fe (0.30), indicating generally low levels of pollution. Seasonal variation was observed, with the highest degree of contamination in winter (7.09) and the lowest in autumn (5.39). The pollution load index ranged from 0.411 in autumn to 0.622 in winter, with an annual average of 0.468, indicating no pollution. The ecological risk factor values, ranging from 0.30 for Fe to 8.97 for As, did not show a significant ecological risk, with As contributing most to the risk. The potential ecological risk index averaged 15.4, which means a very low ecological risk. Additionally, the study confirmed that the overall potential human health risks remained within acceptable limits.
The K?/K? X-ray intensity ratios of Cu and Ag in Cu-Ag thin alloy films
(Pergamon-Elsevier Science Ltd, 2023) Sogut, Omer; Cengiz, Erhan; Ayaz, Durdu Hayrettin; Apaydin, Gokhan
K & beta;/K & alpha; X-ray intensity ratio values of Cu and Ag in CuxAg1-x (x = 53.5, 67.6, 76.9, 85.4, 89.6) thin alloy films produced from two different sources by the physical vapour deposition method have been determined by the Energy Dispersive X-ray Fluorescence Spectroscopy (EDXRF) method. The changes in the crystal structures of CuxAg1-x thin alloy films caused by the changes in the Cu and Ag concentrations, which affect the valence electronic structure have been investigated by the X-ray Diffraction (XRD) techniques. The obtained values were compared with the theoretical and fitted values for pure Cu and Ag elements.
Thickness-Dependent Structural and Electronic Properties of HfO2 Thin Films Probed by XRD and XAFS
(Springer, 2025) Ozkendir, Osman Murat; Cengiz, Erhan; Kanmaz, Imran; Gunaydin, Selen; Apaydin, Gokhan; Harfouche, Messaoud
Hafnium dioxide (HfO2) thin films have garnered significant attention due to their exceptional dielectric, mechanical, and thermal properties, making them ideal for applications in microelectronics, optoelectronics, and energy storage. However, despite extensive research, a comprehensive understanding of their thickness-dependent structural and electronic properties remains incomplete. In this study, we systematically investigate HfO2 thin films (13-115 nm) synthesized via spin coating and characterized using synchrotron-based x-ray absorption fine structure (XAFS) spectroscopy and x-ray diffraction (XRD). High-resolution XRD confirms the monoclinic P2(1)/c phase with high crystallinity and minimal strain, while XAFS analysis reveals thickness-dependent variations in local atomic coordination and electronic structure. XANES spectra demonstrate a systematic shift in the Hf L-3-edge white line, indicating modifications in unoccupied Hf 5d states due to changes in oxygen coordination. EXAFS fitting further quantifies bond distances and coordination numbers, revealing enhanced structural ordering in thicker films. Density functional theory (DFT) calculations corroborate experimental findings, confirming the bandgap (similar to 4.4 eV) and orbital contributions to valence and conduction bands. Our results provide critical insights into defect states, interfacial effects, and thickness-dependent structural modifications, advancing the optimization of HfO2 for next-generation electronic devices.

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