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    Construction and characterization of a boron-doped surface coating for neutron radiation protection
    (Gazi Univ, Fac Engineering Architecture, 2024) Seval, Hakan Kemal; Yagimli, Mustafa; Tozan, Hakan
    Purpose: This study aims to develop an economic and environmental -friendly, non-toxic boron -doped surface coating material that will provide protection against neutron radiation. Theory and Methods: Shielding is one of the three basic elements of radiation protection. Hexagonal boron nitride (h-BN) is taking great attention in recent years due to its mechanical strength, low cost, thermal conductivity, and resistance to oxidation. Studies also illustrated that it has a high neutron shield performance. Characterization of the proposed coating materials which are formed by adding H-BN filler to polyvinyl butyral (PVB) matrix, was done using XRD and SEM. Radiation experiments were carried out with slow (thermal) neutrons in 241Am-Be isotropic neutron source. A slow neutron activation monitor was used for measurements and the nuclear reaction of the indium element was monitored as a neutron activation monitor. The resulting gamma spectra were evaluated with the Maestro -32 and Gamma Vision32 software. Results: Thermal neutron absorption coefficients (macroscopic cross section) of PVB coating materials formulated with h-BN additive at different ratios were calculated. A homogeneous dispersion was formed by the physicochemical interaction between H-BN and PVB molecules. The analyses of the results illustrate that the macroscopic cross-section value and the neutron radiation blocking feature increase as the ratio of the additive material is increased in the formulation. And also, all coating material samples project the ability to shield thermal neutron radiation. Conclusion: The coating material samples illustrated shielding performance by absorbing thermal neutrons at varying rates. The results of the analyses also possessed that, as the ratio of the additive in the coating material is increased, the neutron radiation blocking feature also increases. However, structural deteriorations are observed on the coating material when the amount of boron is more than 50% by mass. In addition to its easy applicability to various surfaces, the coating material also does not require complex manufacturing processes which provides a great advantage.
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    Investigation of the network made with the complementary motor of the thalamus with the DTI method in individuals with tinnitus
    (Kare Publishing, 2024) Elpen Karyemez, Pınar; Yağımlı, Mustafa; Tozan, Hakan
    Objectives:This This study aimed to investigate the differences in the networks between the thalamus and the supplementary motor area in brain MRI examinations of individuals with subjective chronic tinnitus and healthy control groups. Methods: In the study, brain MRI imaging was performed on 47 patients suffering from bilateral tinnitus for two years or more and 42 healthy individuals. The tensor information obtained using the diffusion tensor imaging sequence data obtained from both groups was processed in the DSI Studio program. Brain connection maps were obtained from the data obtained. Quantitative information of the individual connecogram maps of each case was recorded and the groups were compared. Results: In the tinnitus group, there is an increase in the pathways between the thalamus and the supplementary motor area. In addition, it was determined that the pathways of the thalamus with the hippocampus, superior and middle occipital area and frontal area increased, and the pathways with the hippocampus and cerebellum decreased. Conclusion: Important functions of the supplementary motor area and thalamus; These are cognitive actions in which attention plays an important role, such as noticing the stimulus from the environment, planning and implementing the response action. It is thought that changes in the pathways between the thalamus and the supplementary motor area will especially affect attention-related functions.
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    The Time Response Analysis of a Hybrid Electronic Switch and Residual Current Devices System
    (Univ Osijek, Tech Fac, 2024) Yurtcu, Ahmet; Yagimli, Mustafa; Tozan, Hakan
    Residual current devices are vital as they are used to protect humans from electric shocks and fire hazards. These devices detect the residual current in the grid, open the mechanism, and leave the grid without voltage. In this study, the time response of a newly designed hybrid system consisting of an electronic switch system and a residual current device to protect humans from hazards has been analyzed. A model consisting of capacitors and resistors has been used to simulate the human body. In the designed system, the average response time was found to be 1.37 ms, which operates with an average of 6.43 times faster than a conventional residual current device. The results of the study illustrated that the designed system leaves the circuit voltage-free much faster than a conventional residual current device and is more effective in protecting human life.