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Environmental Life Cycle Assessment of Industrial Hazardous Waste Incineration: The Case of Kocaeli, Türkiye
No full textThis study evaluates the environmental performance of a hazardous waste incinerator with integrated electricity generation using a life cycle assessment (LCA) approach. The aim is to quantify the environmental impacts of hazardous waste incineration with energy recovery and to assess improvement options based on circular economy principles. Three systems were examined: the current situation (CS), a scenario including the beneficial reuse of incineration bottom ash (S1), and a carbon capture and utilization scenario involving CO₂-based methanol production (S2). The assessment followed a consequential LCA framework with system expansion to address multifunctionality by crediting avoided environmental impacts. The system boundary was defined as gate-to-grave, covering operational inputs, emissions to air and water, electricity generation, and final disposal of residues. Electricity produced from the Waste-to-Energy (WtE) plant was credited through substitution of the average Turkish electricity mix. The functional unit was set as 1 ton of waste entering the facility. Foreground data were obtained from a large-scale operating hazardous waste incinerator, while background processes were modelled using the Ecoinvent 3.7 database within SimaPro 9.2 Results show that electricity consumption is the major contributor to environmental burdens in the CS, with a climate change impact of 921 kg CO₂-eq per ton of waste. This impact decreased to 856 kg CO₂-eq/ton in S1 and to 51 kg CO₂-eq/ton in S2. Although S2 achieved the lowest impacts in most categories due to CO₂ capture and conversion, it exhibited higher particulate matter formation and freshwater ecotoxicity linked to steam use. S1 performed best in freshwater ecotoxicity through bottom ash reuse and metal recovery. Overall, the findings demonstrate that circular economy strategies and CO₂ capture technologies can significantly enhance the environmental sustainability of hazardous waste management
Advanced exergy analysis of an ejector refrigeration cycle with intercooler for low-temperature applications
No full textImproving the energy and exergy performance of refrigeration cycles has become increasingly important for industrial and low-temperature applications. In this context, this study presents a comprehensive advanced exergy analysis of an ejector intercooler refrigeration cycle (EIRC), marking the first application of such an approach to this configuration in literature. The system integrates an ejector between the high- and low-temperature stages to improve pressure recovery and reduce throttling irreversibilities, thereby enhancing overall performance. The total exergy destruction of the cycle was calculated as 2.075 kW, with the most significant losses occurring in the evaporator (0.397 kW), condenser (0.384 kW), and high temperature cycle (HTC) compressor (0.372 kW). The HTC ejector also exhibited notable destruction at 0.302 kW. The advanced exergy breakdown revealed that 61.18% of the losses were exogenous, and 71.53% were avoidable, with 37.04% being both avoidable and exogenous, indicating strong potential for system-level optimization. Importantly, while conventional exergy efficiency was calculated as 59%, the advanced exergy efficiency increased to 87%, reflecting a 50% relative improvement. These findings demonstrate the viability of EIRC systems and highlight the importance of integrated design strategies for future performance enhancements
Geochemistry and genesis analysis of the Kepekler – Ilıcaboğazı thermal waters (Balıkesir, NW Türkiye)
No full textThe Kepekler-Ilıcaboğazı geothermal field is located in northwest Anatolia, within Balıkesir Province, and comprises both thermal waters and therapeutic clay mud (Peloids). The thermal waters emerge as springs with a temperature range from 30 to 56 °C, with discharge rates of 0.01−4 L/s along a secondary fault in the North Anatolian Fault Zone (NAFZ). Only one (BK-1) production well was drilled to a depth of 390.30 m by General Directorate of Mineral Research and Exploration of Türkiye (MTA), which has a water temperature of 64 °C and a discharge rate of 15 L/sec. This study investigates the chemical and isotopic characteristics of thermal and cold waters using the major ion and trace element contents as well as environmental isotope compositions. The thermal waters belong to the alkaline NaCl-type, and are characterized by pH values of 6.35 and 7.90, generally higher EC (3149–3856 µS/cm), and relatively high concentrations of Cl, Na, B, As, Rb, Li, Cs, and Sr, in contrast to the cold waters, which are primarily of the CaHCO3 type. Carbonate and silicate dissolution, ion exchange, and energy loss through heat conduction are processes responsible for the origin and evolution of NaCl-type water. Thermal waters tend to have lower B/Cl ratios and strong correlations between (Cl and B, Li, and Rb) trace alkali metals and Cl due to rapid, efficient upflow pathways. These features align with high vertical permeability networks that promote efficient upflow and meteoric mixing, delineating the systems of the Kepekler-Ilıcaboğazı area. By estimating reservoir temperatures using chemical geothermometers and saturation indices, reservoir temperature estimates (75–100 °C) may be affected by conductive cooling, mixing, or partial equilibration—especially as most waters plot as "immature" on Giggenbach diagrams. Chemical equilibrium studies show that the thermal waters are in equilibrium with respect to calcite, aragonite, and quartz, while undersaturated with respect to albite, anorthite, K-feldspar, and gypsum. Thermal waters are meteoric in origin as suggested by the isotope (δ18O, δ2H, 3H) composition. Carbon in thermal waters is likely to originate from metamorphic CO2 or marine carbonates whereas carbon in cold waters is derived from an organic source. δ34S sulfur is derived from bacterial sulfate reduction and the dissolution of marine carbonates and sulfide minerals. The study area features a fault-controlled convection deep circulation geothermal system. Thermal waters are sourced from a resource base in the upper crust, which consists of thick granitic and metamorphic rocks that reach the surface. Using the results of hydrogeology and hydrogeochemistry, a conceptual hydrothermal model of recharge, mixing, and discharge has been proposed for the formation of the thermal waters in the study area. This is the first comprehensive geochemical and isotope-based investigation of the Kepekler–Ilıcaboğazı geothermal system, providing new insights into its genesis and evolution
TRAVMATİK EL YARALANMASI OLAN HASTALARDA YARALANMA CİDDİYETİ İLE DİKKAT EKSİKLİĞİ, DÜRTÜSELLİK VE YAŞAM KALİTESİ ARASINDAKİ ILİŞKİ
No full textRadyoterapi Alan Baş ve Boyun Kanseri Hastalarında Algılanan Stres ve Umut: Sosyal Destek ve Başa Çıkma Özyeterliliğinin Zincirleme Etkisi
No full textPersonality traits, perceived social support, and perception of insufficient milk in primiparous mothers: A cross-sectional study
No full textObjective The perception of insufficient milk is a common problem among mothers that is associated with the breastfeeding process and psychological well-being. This study examined the relationship between mothers' personality traits, perceived levels of social support, and perceptions of insufficient milk.Methods The study's sample comprised 323 breastfeeding primiparous mothers with singleton pregnancies and term deliveries, using a descriptive and cross-sectional research methodology. The Big Five Inventory (BFI), Multidimensional Scale of Perceived Social Support (MSPSS), and Perception of Insufficient Milk Supply (PIMS) were used to gather the data. Path analysis was used to examine which personality traits of the mothers were effective in influencing social support. Additionally, it examined the relationship between social support and inadequate milk perception.Results When the relationship between total scale scores was analyzed, it was found that as extraversion (beta = 0.491, P = 0.005), agreeableness (beta = 0.323, P = 0.045) and openness to experience (beta = 0.318, P = 0.038) increased, so too did perceived social support scores, while the perception of milk deficiency decreased (beta = 0.099, P = 0.004).Conclusion Two important factors associated with postnatal breastfeeding were mothers' personality traits and their perception of social support. The results suggest that strengthening social support through targeted programs and support networks might help promote mother-infant interactions and breastfeeding across the prenatal and postnatal periods
An investigation into the analyte-dependent fluorescence quenching of BaTiO₃ nanoparticles for the fluorimetric determination of glucose and paracetamol
No full textThis study investigates the synthesis, characterization, and application of barium titanate nanoparticles (BaTiO₃ NPs) as a fluorimetric sensing platform. Nanocrystalline BaTiO₃ particles, exhibiting quasi-spherical morphology with average diameters evolving from approximately 7 to 9 nm depending on reaction time, were successfully prepared via a room-temperature chemical synthesis route. Comprehensive characterization using techniques such as XRD, SAED, TEM, FTIR, and UV–Vis spectroscopy confirmed the formation of a polycrystalline perovskite structure and elucidated the material's morphological and optical properties. The synthesized BaTiO₃ NPs displayed stable, intrinsic fluorescence, optimally emitting at 467.42 nm upon excitation at ∼402.33 nm in a neutral pH environment (pH 7). This fluorescence was observed to be effectively quenched by multiple analytes, including glucose and paracetamol, establishing a basis for the development of a sensor. Quantitative analysis revealed analyte-dependent quenching efficiencies, with Stern-Volmer studies indicating glucose as the most potent quencher among those kinetically analyzed. The system demonstrated sensitive detection capabilities, achieving low parts-per-million (ppm) limits of detection (LOD) for both glucose (∼1.19 ppm) and paracetamol (∼1.04 ppm). Notably, the linear dynamic response range varied significantly, extending up to ∼1.8 ppm for glucose but reaching at least 3.6 ppm for paracetamol. The demonstrated fluorescence stability, coupled with sensitive and analyte-dependent quenching responses, highlights the potential of these BaTiO₃ nanoparticles as a versatile and robust material for developing future fluorimetric sensors
Clinical and Histopathological Characteristics of Granuloma Annulare: Significance of Giant Cells and Systemic Inflammatory Markers
No full textBackground: Granuloma Annulare (GA) is a chronic inflammatory dermatosis with diverse presentations, yet comprehensive data integrating histopathology, long-term prognosis, and systemic inflammatory markers remain limited. This study aimed to analyze these clinicopathological characteristics and identify biomarkers for chronicity and recurrence. Methods: In this retrospective cohort study, we evaluated 34 patients with histopathologically confirmed GA diagnosed between 2013 and 2023. Demographic data, clinical features, comorbidities, treatment outcomes, and laboratory parameters were analyzed. Histopathological findings were re-evaluated to assess pattern types and the presence of specific markers. Statistical correlations between clinical parameters, inflammatory markers, and histopathological features were assessed. Results: The interstitial pattern was the predominant histopathological subtype (64.7%), with universal mucin deposition (100%). A statistically significant positive correlation was observed between lesion duration and the presence of multinucleated giant cells (r = 0.456, p = 0.033), suggesting a time-dependent granuloma maturation. Clinically, generalized GA cases demonstrated significantly longer recovery times compared to localized forms. The overall recurrence rate was 23.5%. A lower BLR was significantly associated with disease recurrence (r = −0.539, p = 0.021). At least one comorbidity was present in 76.5% of the patients. Conclusions: Our findings suggest that giant cell formation serves as a histopathological marker of lesion chronicity, supporting the concept of granuloma remodeling over time. Furthermore, a suppressed BLR may serve as a novel surrogate marker associated with disease recurrence. Given the high burden of comorbidities observed in both localized and generalized forms, GA should be approached as a cutaneous manifestation of underlying systemic dysregulation, suggesting that clinicians should consider routine metabolic screening for these patients.</jats:p
