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Article Türkiye’de İklim Değişikliği: Yapısal Kırılma Analizinden Kanıtlar(2026) Ekinci, Mehmet; Şentürk, Muhammet ŞakirSince the second half of the 20th century, scientific evidence has firmly established climate change as an irreversible and serious global issue, leading to a steady increase in the number of studies addressing the topic. Temperature and precipitation are two primary indicators of climate change. This study investigates the presence of climate change in Türkiye’s NUTS-2 regions by examining long-term trends in these two variables. Data covering the period from 1950 to 2021 were obtained from the station-based records of the Turkish State Meteorological Service. The datasets were aggregated by NUTS-2 regions, and the Bai-Perron multiple structural break analysis was applied to identify significant shifts in temperature and precipitation patterns. The analysis detected structural breakpoints in average temperature across 25 out of 26 regions, with the exception of the TRA1 region (which includes Erzurum, Erzincan, and Bayburt provinces). These breakpoints primarily occurred during the 1990s and early 2000s. Across all regions, temperatures exhibited varying degrees of increase. The most significant temperature rise was observed in the TRB2 region (Van, Muş, Bitlis, and Hakkari), while the smallest increase occurred in the TR81 region (Zonguldak, Karabük, and Bartın). No structural breakpoints were identified in precipitation levels, suggesting that the pronounced changes in temperature have not yet been mirrored in precipitation patterns. However, when precipitation trends were analyzed relative to the years in which temperature breakpoints occurred, notable regional variations in precipitation amounts were observed. The effects of urbanization and industrialization on temperature change were also examined. The analysis revealed a statistically significant relationship between temperature change and urbanization, but no significant relationship with industrialization.Article Citation - Scopus: 2Effect of Geothermal Water Composition and Pretreatment on the Product Water for Boron-Sensitive Crops(Turkish Energy Nuclear and Mining Research Institute, 2021) Güler, EnverThe membrane filtration is an effective way to produce water for human consumption, industrial use, or irrigation purpose. In this study, a brackish water reverse osmosis (BWRO) membrane was practically investigated to obtain irrigation water from geothermal water. The quality of the produced water was analyzed to understand the potential in agricultural use for boron-sensitive crops. The effects of the feed solution composition and pretreatment by microfiltration were studied. Results showed that the ionic content was effective in reduction of permeate flux. However, the rejections of salt and silica did not change significantly by the change in the feed water composition and they were successfully removed from the geothermal water by more than 95% rejection. Pretreatment of the geothermal water with a microfiltration (MF) membrane having a pore-size of 0.8 μm provided higher flux than the one having a pore size of 5 μm. The higher rejections of boron were only achieved with increased pH in the pretreatment. The pH of 9.5 in the geothermal water provided a rejection of boron as 75% with a permeate boron concentration of 2.4 mg/L when 15 bar of operating pressure was employed. This level of boron concentration in the irrigation water was found to be allowable only for some boron resistant crops (e.g. beans, lettuce, onion) and semi-sensitive crops (e.g. sunflower, potato, tomato).Article Influence of Temperature on Activated Sludge Systems(2018) Balku, ŞaziyeThe present study aims to determine the influence of temperature in the treatment efficiency of the activated sludge systems. To reach this aim, a simulation study is performed using Matlab® programming language. A biological tank is modelled by the ASM3 (activated sludge model No. 3) and a settling tank is modelled by Takács settling velocity model. For a defined inflow rate and inlet waste water characteristics with the predefined design and operational parameters, the treatment model is simulated. The changes in the kinetic parameters by temperature are estimated from the values given in ASM3 and the dissolved oxygen saturation concentration in water is also concerned as a function of temperature. All the other design and the operational conditions are kept constant during simulations. The simulation algorithm is executed for the temperatures 0°C, 10°C, 20°C, and 30°C. The results show that chemical oxygen demand and total suspended solids reduce slightly with increasing temperature, however, the total nitrogen content in the effluent is changing, first increases for the temperatures 10°C, 20°C, and then decreases for 30°C when it is compared to that of at 0°C. The change in temperature affects mostly the ammonium concentration in the waste water treatment systems.Article Theoretical Investigation of Carbon Dioxide Capture by Aqueous Boric Acid Solution: a Termolecular Reaction Mechanism(2018) Kayı, HakanHitherto, boric is suggested and used as a promoter or catalyst for carbondioxide capture in various chemical absorption reactions, such as, absorptionby aqueous potassium carbonate solution to increase mass transfer rate. Butin this study, a single step termolecular reaction mechanism is suggested forthe chemical absorption of carbon dioxide directly by boric acid and water. Thereaction thermochemistry and reaction kinetics for termolecular mechanism areinvestigated by using density functional theory calculations at the B3LYP/6-31G(d)level of theory by taking into account of the implicit solvent effects of water throughthe polarizable continuum model and dispersion corrections. The findings obtainedfrom theoretical calculations indicate that it is possible to capture carbon dioxidewith boric acid in the form of B(OH)2OCOOH.
