Balıkesir Üniversitesi Kurumsal Akademik Arşivi
DSpace@Balıkesir, Balıkesir 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
Triassic volcanism in the Afyon Zone (NW Türkiye): Evidence from U-Pb zircon ages, Sr-Nd isotopes, and geochemistry of an enriched mantle source
(Springer Wien, 2026) Aslan, Zafer; Aydoğan, M. Selman; Kadıoğlu, Y. Kağan; Yiğit, Özcan
In the northwestern part of the Afyon Zone, along the northern margin of the Anatolide-Tauride Block, which is generally regarded as a fragment of northern Gondwana during the Late Paleozoic, Triassic metavolcanic rocks are extensively exposed. These rocks comprise felsic and basic types distinguished by mineralogical and geochemical variations. Zircon U-Pb dating of the felsic metavolcanics yields an age of 233.4 +/- 2.1 Ma, indicating a Triassic magmatic episode. Metavolcanics have high potassium-shoshonitic and calc-alkaline characteristics. They are enriched in large-ion lithophile elements (LILE), and depleted in high-field-strength elements (HFSE). They also show enrichment in light rare earth elements (LREE) relative to heavy rare earth elements (HREE). The relative enrichment of low-field-strength elements (LFSE) over HFSE, along with average (La/Lu)N ratios of 3-25, reflects typical calc-alkaline volcanism. The geochemical trends suggest that assimilation and/or crustal contamination may have occurred during magma evolution. Furthermore, they are considered to be related to the island arc and resemble Tholeiitic-type mid-ocean ridge basalts. Isotope data supports an enriched mantle source. The initial Sr-8(7)/Sr-8(6) isotope ratios are 0.711429-0.716276 in metadacite and 0.709275-0.714190 in metabasic. The 143Nd/144Nd isotope ratios vary from 0.512349 to 0.512369 in metadacite, and from 0.512463 to 0.512509 in metabasic. The geochemical and isotopic data suggest that the parental magmas were derived from an enriched mantle source metasomatized by subduction-related components beneath the Afyon Zone. The northward subduction of the Paleozoic Tethyan oceanic lithosphere under the southern margin of Laurasia during the Triassic is interpreted to have triggered a regionally rift-related regime along the northern margin of Gondwana. The Triassic metavolcanic rocks are interpreted to represent the earliest magmatic products associated with the Paleotethys Ocean crust, formed along the northern margin of Gondwana.
Thermoluminescence and anomalous heating-rate behavior in SmBa3B9O18: Evidence for hierarchical trap distribution and strong retrapping dynamics
(Pergamon-Elsevier Science Ltd, 2026) Hakami, Jabir; Madkhali, O.; Oğlakçı, M.; Cin, E. A.; Karalı, E. Ekdal; Orucu, H.; Çoban, Mustafa Burak; Kaynar, U. H.
SmBa3B9O18 nanostructures were synthesized by a sol-gel assisted microwave combustion route and subsequently calcined at 800 degrees C, yielding a crystalline rare-earth-based borate host lattice for detailed thermoluminescence (TL) characterization. X-ray diffraction and Rietveld refinement confirm the formation of a single-phase structure with high crystallinity and well-defined lattice parameters. TL measurements recorded in a 565 nm band-pass detection window reveal well-resolved multi-peak glow curves suitable for detailed kinetic analysis. Preheating at 150 degrees C for 8 s effectively removes shallow traps and stabilizes the dosimetric signal, yielding dominant glow peaks at similar to 220 degrees C and similar to 290 degrees C associated with thermally stable trapping centers. The material shows a nearly linear dose response up to similar to 60 Gy, followed by controlled supralinearity up to 500 Gy, together with a low minimum detectable dose (similar to 0.13 Gy) and excellent reusability, with cycle-to-cycle deviations within +/- 5%. Variable heating-rate experiments (0.2-4 degrees C s(-1)) reveal pronounced anomalous heating-rate behavior, where both peak intensity and integrated TL signal increase with heating rate, deviating from conventional kinetic models. Combined various-heating-rate, T-m-T-stop and initial-rise analyses (with thermal-lag correction) yield activation energies of similar to 1.6-1.7 eV and similar to 1.9-2.0 eV for the main peaks and reveal characteristic plateau-shift behavior consistent with a hierarchical trap system comprising multiple overlapping and partially distributed trapping levels. Fading analysis shows non-monotonic behavior, with an initial TL increase of up to similar to 20% around 12 h followed by gradual decay, attributed to post-irradiation charge redistribution and thermally assisted retrapping within a coupled trap system. These results demonstrate that SmBa3B9O18 is a promising TL dosimetric material, combining high structural stability, sensitive and reusable response, and complex non-classical luminescence kinetics governed by coupled trap-recombination dynamics.
Fatal carbon monoxide poisoning in older adults: findings from a 15-year series of forensic autopsies in Turkey
(Frontiers Media Sa, 2026) Kıyak, Samet; Atan, Yusuf; Taşkın, Gökhan; Kıyak, Ramazan; Dündar, Ahmet Sedat
Objective This study aimed to retrospectively evaluate the demographic, toxicological, and pathological characteristics of individuals aged 65 and older who died due to carbon monoxide (CO) poisoning and underwent autopsy.Materials and methods Cases aged 65 years and older who were determined to have died from carbon monoxide poisoning at autopsy were analyzed in terms of age, gender, time of death, place of death, source of CO exposure, carboxyhemoglobin levels, toxicological findings, and accompanying chronic diseases.Results The mean age of the 115 cases included in the study was 74.6 +/- 7.03 years, and 58.3% were male. Sixty percent of deaths occurred during winter months, and 84.3% occurred in domestic settings. The most common source of CO exposure was stoves, accounting for 71.3%. Carboxyhemoglobin levels were mostly in the range of 40-79%, while only 4.3% of cases had carboxyhemoglobin levels above 80%. Various pharmaceutical agents were detected in 43.5% of cases, and ethyl alcohol alone was detected in 4.3% of cases. Among accompanying chronic diseases, cardiovascular system diseases (69.6%) were the most common.Conclusion Carbon monoxide poisoning remains an important cause of death among older adults. Fatal cases were predominantly associated with domestic exposure, stove use, and winter months. Cardiovascular and pulmonary comorbidities were common among the victims, highlighting the vulnerability of older populations to fatal carbon monoxide exposure.
Charge-compensated Eu³ ⁺ luminescence in BaZr(BO₃)₂: Effect of Li⁺/Na⁺/K⁺ Co-doping on local symmetry, defect chemistry and radiative properties
(Elsevier Science Sa, 2026) Hakami, Jabir; Karaman, T.; Cin, E. A.; Özmen, O.T.; Madkhali, O.; Çoban, Mustafa Burak; Kaynar, U. H.; Tas, B.; Aydin, H.; Can, N.
BaZr(BO3)2:Eu3+ red phosphors were prepared via a microwave-assisted sol-gel auto-combustion approach, in which Li+, Na+, and K+ ions were systematically varied and introduced as alkali co-dopants to enhance luminescence performance and provide effective charge compensation. Rietveld refinement of X-ray diffraction (XRD) data confirms the formation of a phase-pure trigonal BaZr(BO3)2structure (space group R3c), while Fourier-transform infrared (FTIR) and Raman spectroscopy analyses reveal that the BO3-ZrO6 framework remains largely intact, with only slight local distortions induced by doping. Under 393 nm excitation, the phosphors display the characteristic Eu3+ (5D0 -> 7FJ) emission transitions, predominantly governed by the hypersensitive 5D0 -> 7F2 transition centered at approximately 612 nm, resulting in intense red emission with high color purity. The optimal Eu3+ concentration is determined to be 3 wt%, with concentration quenching attributed to longrange dipole-dipole interactions. Alkali-ion co-doping markedly enhances photoluminescence intensity by facilitating charge compensation and mitigating defect states. Among the introduced alkali ions, Na+ yields the highest emission enhancement (approximately 12-fold relative to the Eu3+ doped sample) along with comparatively improved thermal stability, whereas K+ effectively extends the 5D0 excited-state lifetime, and Li+ promotes increased local structural asymmetry and stronger Eu-O covalency, as evidenced by the Judd-Ofelt intensity parameter Omega 2. Temperature-dependent photoluminescence studies further suggest that the improved thermal stability in co-doped samples is associated with reduced defect-assisted non-radiative recombination pathways. These findings highlight that Na+/K+/Li+-compensated BaZr(BO3)2:Eu3+ phosphors represent promising red-emitting candidates for near-UV/blue-excited white light-emitting diodes (LEDs), where performance is critically governed by the interplay between local symmetry modulation and defect suppression mechanisms.
From wage dissatisfaction to union expectations: The mediating role of union perception among nurses
(John Wiley and Sons Inc, 2026) Tosun, Salih; Cerev, Gökçe; Sariipek, Doğa Başar
Aim: This study examines the relationships between wage satisfaction, union perceptions, expectations, and union membership among Turkish nurses, identifying factors associated with union participation. Design: Sequential explanatory mixed-methods design. Methods: This two-phase study (January–July 2023) included: (1) a quantitative survey of 210 nurses assessing wage satisfaction, union perceptions, and expectations, analysed using regression and PROCESS Macro (Model 4); and (2) qualitative interviews with 22 nurses, including 15 with union leadership experience, analysed through thematic analysis using MAXQDA. Results: Quantitative findings indicated that wage satisfaction was associated with nurses' perceptions of unions but did not independently predict union expectations. The study hypothesises that union perception functions as a key mediating mechanism, translating wage dissatisfaction into expectations for union action. Qualitative findings supported this pattern, showing that although wage dissatisfaction was widespread, nurses' expectations were primarily shaped by perceptions of unions' transparency, political independence, democratic participation, and representational capacity rather than by wages alone. Conclusions: Union participation among nurses is influenced by both economic conditions and normative evaluations of unions. While wage dissatisfaction provides an important contextual background, expectations and engagement are mainly driven by perceptions of union credibility, fairness, and representational effectiveness. Implications for Profession and/or Patient Care: Nursing unions should prioritise transparent governance, democratic participation, and political independence to enhance trust, member engagement, workforce stability, and quality of care. Impact: This study addresses persistent wage dissatisfaction alongside declining union membership and trust. The findings demonstrate that union engagement depends not only on economic dissatisfaction but also on perceived representational fairness. The results are particularly relevant for nursing unions, professional organisations, and policymakers aiming to strengthen union legitimacy and workforce engagement in healthcare systems. Reporting Method: Compliant with COREQ guidelines and mixed-methods reporting standards. Patient or Public Contribution: No patient or public contribution.
