Tıbbi Görüntüleme Teknikleri Programı / Medical Imaging Techniques Program
http://hdl.handle.net/20.500.12566/559
2024-03-19T06:07:14ZAssessment of neutron and gamma-ray shielding characteristics in ternary composites: experimental analysis and Monte Carlo simulations
http://hdl.handle.net/20.500.12566/1964
Assessment of neutron and gamma-ray shielding characteristics in ternary composites: experimental analysis and Monte Carlo simulations
Akman, Ferdi; Kılıçoğlu, Özge; Oğul, Hasan; Özdoğan, Hasan; Kaçal, Mustafa Recep; Polat, Hasan
The research aims to exploring the gamma-ray shielding capacities of polyacrylonitrile/chrome-filled polymer composites through a combination of experimental, theoretical and simulation methods. Additionally, employing MCNPv6 and GEANT4 simulation tools, the study evaluates the materials' performance against neutron radiation. The materials were subjected to various gamma-ray energy levels, and their shielding efficacies are analytically quantified using parameters such as Radiation Protection Efficiency (RPE), Mass Attenuation Coefficient (MAC), Linear Attenuation Coefficient (LAC), and Half-Value Layer (HVL). At various neutron energies and sample thicknesses, the numbers of transmitted neutrons were evaluated. Notably, composite P0Cr50 (not contain polyacrylonitrile and containing 50% chromium) emerges prominently, demonstrating superior radiation shielding characteristics against both gamma and neutron radiations. This attitude is attributed to its optimal chrome dispersion and density, positioning it as a promising candidate for radiation shielding applications in industrial and nuclear domains.
2024-06-01T00:00:00ZMass attenuation coefficient, stopping power, and penetrating distance calculations via Monte Carlo simulations for cell membranes
http://hdl.handle.net/20.500.12566/1899
Mass attenuation coefficient, stopping power, and penetrating distance calculations via Monte Carlo simulations for cell membranes
Üncü, Yiğit Ali; Sevim, Gençay; Ağar, Osman; Özdoğan, Hasan
The Monte Carlo (MC) method is a computer simulation that is widely used in different disciplines including physics, biology, biophysics, medical imaging, biomedical engineering, etc. In addition, MC method is often used to simulate the interaction of radiation with cells, tissues, and the environment. In the present study, mass attenuation coefficient, stopping power, and penetrating distance calculations were performed for cell membranes having an approximately 60-100Å thickness. These calculations have been done for lipid bilayer structure of cell membrane via MC techniques employing two of the most known computer-aided calculation and simulation software which are MC methods such as SRIM-2013 (The Stopping and Range of Ions in Matter) and MCNPv6 (Monte Carlo N-Particle) with XCOM software. Stopping power and penetrating distance calculations were obtained using SRIM-2013. Also, both XCOM software and MCNPv6 simulation code were used to obtain photon interaction parameters within the energy range of 0.01 – 10000keV. Obtained all results from different codes have been visualized by graphing for evaluation.
2023-01-01T00:00:00Z209Bi izotopunun (p,xn), (p,xp), (p,xd) ve (p,xt) reaksiyonlarının teorik nükleer modeller ile incelenmesi
http://hdl.handle.net/20.500.12566/1898
209Bi izotopunun (p,xn), (p,xp), (p,xd) ve (p,xt) reaksiyonlarının teorik nükleer modeller ile incelenmesi
Özdoğan, Hasan; Üncü, Yiğit Ali
Nükleer fizik alanındaki gelişmeler; arkeoloji, jeoloji, mühendislik, astrofizik, kozmoloji, kimya, biyoloji, tıp gibi bilim dallarını da etkilemektedir. Nükleer reaksiyon mekanizmalarını anlamak, reaksiyon modelleri oluşturmak ve mevcut nükleer reaksiyon modellerinin geçerliliğini değerlendirmek için nükleer modellerin incelenmesi gereklidir. Bu çalışmada protonlarla bombardıman edilen 209-Bi (209Bi) izotopunun nötron, proton, döteryum ve trityum yayınlanma spektrumları incelenmiştir. Çalışmadaki sonuçlar, TALYS 1.95 nükleer reaksiyon kodu kullanılarak yapılmış, elde edilen sonuçlar Uluslararası Deneysel Nükleer Reaksiyon Data (EXFOR) kütüphanesinden elde edilen deneysel verilerle karşılaştırılmıştır. Sonuç olarak incelenen, direkt reaksiyon, bileşik çekirdek ve denge öncesi mekanizmalarının sonuçları deneysel veriler ile uyumlu olarak çıkmıştır.; Recent developments in nuclear physics also affect branches of science such as archeology, geology, engineering, astrophysics, cosmology, chemistry, biology, and medicine. Examining nuclear models is necessary to understand nuclear reaction mechanisms, construct reaction models, and evaluate the validity of existing nuclear reaction models and for use in nuclear physics applications. In this study, neutron, proton, deuterium, and tritium emission spectra of 209-Bi (209Bi) isotope bombarded with protons has been investigated. The results of the study have been made using the TALYS 1.95 nuclear reaction code, and the results have been compared with the experimental data obtained from the International Experimental Nuclear Reaction Data (EXFOR) library. Consequently, the results of the direct reaction, compound nuclei, and pre-equilibrium mechanisms examined have been in agreement with the experimental data.
2023-01-01T00:00:00ZNeural network predictions of (α, n) reaction cross sections at 18.5±3 MeV using the Levenberg-Marquardt algorithm
http://hdl.handle.net/20.500.12566/1880
Neural network predictions of (α, n) reaction cross sections at 18.5±3 MeV using the Levenberg-Marquardt algorithm
Özdoğan, Hasan; Üncü, Yiğit Ali; Şekerci, Mert; Kaplan, Abdullah
In recent developments, artificial neural networks (ANNs) have demonstrated their capability to predict reaction cross-sections based on experimental data. Specifically, for predicting (a,n) reaction cross-sections, we meticulously fine-tuned the neural network’s performance by optimizing its parameters through the Levenberg-Marquardt algorithm. The effectiveness of this approach is corroborated by notable correlation coefficients; an R-value of 0.90928 for overall correlation, 0.98194 for validation, 0.99981 for testing, and 0.94116 for the comprehensive network prediction. We conducted a rigorous comparison between the results and theoretical computations derived from the TALYS 1.95 nuclear code to validate the predictive accuracy. The mean square error value for artificial neural network results is 7620.92, whereas for TALYS 1.95 calculations, it has been found to be 50,312.74. This comprehensive evaluation process validates the reliability of the ANN based on the Levenberg-Marquardt algorithm in approximating the reaction sections, thus demonstrating its potential for comprehensive investigations. These recent developments confirm the feasibility of using ANN models to gain insight into (a,n) reaction cross-sections
2024-01-01T00:00:00Z