Recep Tayyip Erdoğan Üniversitesi Kurumsal Akademik Arşivi
DSpace@RTEÜ, Recep Tayyip Erdoğan Üniversitesi tarafından doğrudan ve dolaylı olarak yayınlanan; kitap, makale, tez, bildiri, rapor, araştırma verisi gibi tüm akademik kaynakları uluslararası standartlarda dijital ortamda depolar, Üniversitenin akademik performansını izlemeye aracılık eder, kaynakları uzun süreli saklar ve yayınların etkisini artırmak için telif haklarına uygun olarak Açık Erişime sunar.
Güncel Gönderiler
Optical and electrical properties of SiC/p-Si heterojunction
(Springer, 2026) Taşyürek, Lütfi Bilal; Orak, İkram; Sarılmaz, Adem; Özel, Faruk
In this study, SiC was used to manufacture Al/SiC/p-Si/Al heterojunction structure by thermal evaporation method. X-ray diffractometry (XRD) and field emission scanning electron microscope (FE-SEM) analyses were evaluated for the characterization of semiconductor SiC layers. For the electrical characterization of the heterojunction, current-voltage (I-V), capacitance-voltage (C-V), and conductance-voltage (G-V) parameters were measured at room temperature (RT) and under various illumination conditions. Ideality factor (n) and barrier height (Фb) values were calculated as 1.32 and 0.85 eV in the dark and 1.22 and 0.77 eV at 100 mW/cm2 illumination at RT, respectively. The results provide information indicating that Al/SiC/p-Si/Al heterojunction structure is promising for photovoltaic devices.
Multilayer perceptron neural network approach for power quality improvement in a grid integrated PV and electric vehicle systems
(Public Library of Science, 2026) Das, Soumya Ranjan; Sabhahit, Jayalakshmi Narayana; Patro, K. Abhimanyu Kumar; Acharya, Devi Prasad; Mohanty, Asit; Cüce, Erdem
Recently, there has been an increase in the grid integration of electric vehicles (EVs) and solar photovoltaic (PV) systems, primarily driven by two goals: lowering energy costs and decreasing emissions. Numerous research studies have concentrated on the separate effects of integrating PVs and EVs into the grid. Nevertheless, it is important to recognize that as the adoption of PVs and EVs continues to grow, the supply grid will face the cumulative effects of PV and EV integration on power quality (PQ) challenges. To provide a comprehensive understanding, this study examines the joint impact of PVs and EVs on PQ aspects in detail. This study has indicated that EVs and PVs alone can adversely impact grid reliability and PQ because of the variable character of PV source and the unpredictability of EV demand. But multiple research efforts have shown that coordination between PVs and EVs can help to alleviate certain problems that arise from their individual integration. This study demonstrates PQ enhancement in a grid system integrated with PV and EV using a multilayer perceptron neural network (MLPNN) approach. In the system with PV integration, the GWO-ANFIS, MPPT technique is employed for optimizing power extraction. Under balanced non-linear loading conditions, simulation results show that the THD is initially 25.97% without compensation, then decreases to 12.57% with a shunt passive filter (SPF), 3.37% with the application of recursive least squares (RLS), and 1.37% with MLPNN. With much lower THD and quicker convergence, the suggested MLPNN-based controller exhibits improved harmonic mitigation. A comparison between the proposed and existing methods are drawn using the MATLAB/ Simulink platform.
Sex-specific differences in basilar artery vasospasm after subarachnoid hemorrhage: evidence from a rabbit model
(Frontiers Media SA, 2026) Daltaban, İskender Samet; Kanat, Ayhan; Gel, Mehmet Selim; Aydın, Mehmet Dumlu; Demirtaş, Rabia
Background – Subarachnoid hemorrhage (SAH) remains a devastating cerebrovascular disorder in which cerebral vasospasm is a key determinant of secondary injury and outcome. Sex differences are well-documented clinically, women exhibit a higher incidence of aneurysmal SAH and often worse outcomes, but whether biological sex influences vasospasm severity in controlled preclinical settings remains unclear. Methods – In a randomized, controlled rabbit model, we investigated sex-specific differences in basilar artery (BA) vasospasm after SAH. Twenty-four New Zealand White rabbits (12 male, 12 female) were allocated to Control, SHAM, or SAH groups. SAH was induced by cisterna magna injection of autologous blood; SHAM animals received saline. On Day 7, BA segments were harvested for quantitative assessment of vasospasm using the Vasospasm Index (VSI: wall area/lumen area) and blinded qualitative histopathological scoring of smooth muscle contraction, endothelial integrity, internal elastic membrane configuration, and adventitial thickness. Nonparametric statistical tests were used, with male vs. female comparison in SAH as the primary endpoint. Results – Control and SHAM animals showed no significant sex differences in VSI (Control: p = 0.47; SHAM: p = 0.06). In contrast, SAH induced severe vasospasm in males (VSI 2.34 ± 0.63) compared with moderate vasospasm in females (1.27 ± 0.49, p < 0.001). Histopathology corroborated these findings, with severe endothelial disruption and smooth muscle hypercontraction in males versus moderate alterations in females. Conclusion – Male rabbits exhibited significantly more severe vasospasm than females after SAH, despite human epidemiology suggesting greater vulnerability in women. These results demonstrate sex as a fundamental biological variable in SAH pathophysiology and underscore the need for mechanistic studies exploring hormonal, autonomic, and inflammatory mediators. Incorporating sex into experimental design may ultimately inform sex-specific therapeutic strategies for SAH.
In Silico characterization of acylamidase from Actinoalloteichus hoggarensis: A promising biocatalyst for the bioremediation of persistent organic pollutants
(Elsevier, 2026) Zergoun, Sara; Abayahia, Ikrame; Bakli, Mahfoud; Beriş, Fatih Şaban; Ahmad Hidayat, Ahmad Fadhlurrahman; Bin Mohamad, Saharuddin; Munir, Muhammad
Widespread contamination by persistent organic micropollutants, particularly polycyclic aromatic hydrocarbons (PAHs) from petrochemical activities, poses risks to ecosystems and human health, necessitating sustainable remediation strategies. Enzymatic bioremediation offers a promising alternative, with amidases emerging as versatile catalysts. This study investigates the catalytic potential of an acylamidase from Actinoalloteichus hoggarensis , a thermotolerant and halotolerant actinobacterium isolated from the Algerian Sahara Desert, whose extremophilic origin suggests inherent stability for harsh conditions. Using a comprehensive in silico approach, the enzyme's structural and functional properties were characterized, and its interactions with 34 micropollutants were evaluated via molecular docking. A high-quality three-dimensional model was generated and validated. Conserved domain analysis classified the enzyme within the amidase signature family. Molecular docking revealed strong binding affinities across diverse contaminants. Among PAHs, benzo[ a ]pyrene exhibited the strongest affinity, followed by chrysene and anthracene. The enzyme also showed notable interactions with the plastic additive triphenyl phosphate, highlighting its substrate versatility. Molecular dynamics simulations confirmed the stability of enzyme-ligand complexes (RMSD < 0.35 nm) and provided insights into key binding residues. These results indicate that this acylamidase possesses structural determinants accommodating both PAHs and other organic micropollutants, providing a computational foundation for its application in enzymatic bioremediation.
Creep behavior of palm fiber reinforced epoxy composites: Experimental analysis and environmental implications
(Elsevier, 2026) Boukhlif, Amel; Zengah, Sahnoun; Baltach, Abdelghani; Baltach, Abdelghani; Djebli, Abdelkader; Bendouba, Mostefa; Uzun Yaylacı, Ecren; Yaylacı, Murat
This study investigates the combined effects of temperature and palm fiber reinforcement on the mechanical and creep behavior of epoxy-based composites. The viscoelastic response was evaluated from 20°C to 80°C, focusing on instantaneous strain, time-dependent deformation, and steady-state creep rate (min−1). The incorporation of palm fibers increased the ultimate tensile strength from approximately 20 MPa for neat epoxy to 37 MPa and 55 MPa for composites reinforced with one and two palm fiber layers, respectively. Young's modulus also increased from 3.15 GPa for neat epoxy to 3.41 GPa for the two-layer composite, indicating an improvement of about 8.3%. The results show a strong thermo-activated creep mechanism, where increasing temperature enhances molecular mobility, reduces polymer viscosity, and increases deformation in neat epoxy. In contrast, palm fiber reinforcement markedly improves the mechanical stability and creep resistance of the epoxy matrix. Under a nominal dead-weight load of 1000 g (9.81 N), the maximum creep strain decreased from approximately 0.24 for neat epoxy to 0.205 and 0.165 for the one-layer and two-layer palm fiber composites, respectively. In addition, the two-layer composite reduced the maximum creep strain by approximately 37%, 34%, and 31% under applied loads of 400 g, 600 g, and 1000 g, respectively. These improvements are attributed to efficient stress transfer, restricted polymer-chain mobility, and the reinforcing effect of the fiber network. Overall, the results demonstrate that palm fiber reinforcement enhances both mechanical performance and long-term creep resistance, making these composites suitable for lightweight structural applications under moderate thermal environments.
