GCRIS Database | IYTE
http://gcris.iyte.edu.tr:80
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2024-03-25T04:32:11Z
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An efficient method of improving essential oil retention and sustained release of chitosan films: Ultrasound-assisted preparation of chitosan composites with surface active chickpea proteins
https://hdl.handle.net/11147/14338
Title: An efficient method of improving essential oil retention and sustained release of chitosan films: Ultrasound-assisted preparation of chitosan composites with surface active chickpea proteins
Authors: Barış Kavur,P.; Yemenicioğlu,A.
Abstract: This work aimed at preparing chitosan (CHI) composites with surface active chickpea protein (CP) showing better eugenol (EUG) retention and sustained release capacity than pristine CHI films. For this purpose, ionic complexation of CHI with CP (CHI:CP ratio = 2:1, w/w) in the presence of EUG at pH 5.0 was achieved using mechanical homogenization alone (HM) or in combination with ultrasonic homogenization (HM-HUS). The HM-HUS treatment provided better solubility of CP (4.4-fold), increased emulsified EUG in film-forming solutions, and denser films than HM treatment. The composite films obtained using HM-HUS (FLMCHI-CP-EUG/HM-HUS) retained 1.2–1.4-fold higher EUG after drying, and showed almost 2-fold slower EUG release in air at room temperature than composite films prepared by HM, and control CHI films prepared by HM (FLMCHI-EUG/HM) or HM-HUS (FLMCHI-EUG/HM-HUS). The FLMCHI-CP-EUG/HM-HUS films also showed better moisture barrier and mechanical properties than other films. The developed films were proved in a challenging coating application with onions. Escherichia coli and Listeria innocua counts of inoculated and FLMCHI-CP-EUG/HM-HUS (average coating thickness = 4.5 ± 1.3 μm) coated onions were significantly lower than those of uncoated (2.8 and 3.8 log) and FLMCHI/HM-HUS (1.4 and 1.3 log) coated onions after 5-days at room temperature. FLMCHI-CP-EUG/HM-HUS coating also reduced percentage of sprouted onions from 30 to 10% during storage. EUG odor of coated onions could not have been detected by 80% of panelists after 4 weeks. Compositing with CP boosts the performance of essential oil loaded CHI films by enabling use of film matrix as an encapsulant. © 2024 Elsevier Ltd
2024-01-01T00:00:00Z
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Numerical modeling of the CO2 injection in the Kızıldere geothermal field using multiple inter-well tracer tests
https://hdl.handle.net/11147/14340
Title: Numerical modeling of the CO2 injection in the Kızıldere geothermal field using multiple inter-well tracer tests
Authors: Sevindik,D.B.; Erol,S.; Akin,S.
Abstract: Many geothermal power plants in Turkey emit high amounts of non-condensable gas (NCG), consisting mainly of CO2. Thus, it is crucial to mitigate the NCG emissions by re-injecting the captured gas back into the reservoir. In this study, a numerical sector reservoir model is developed to inspect how the reinjected NCG dissipates in the reservoir for successful sequestration. To accurately characterize the flow characteristics in the reservoir, chloride concentrations observed at the production wells were matched. Furthermore, two multi-well slug tracer tests (one with NCG injection well and one from the northernmost shallow injection well by using different naphthalene-sulphonates) results have been used to calibrate the numerical model. Consequently, a high degree of quantitative and qualitative characterization of the reservoir section near the injection site has been achieved. Using the calibrated model, the impact of CO2-brine injection has been studied for different injection scenarios with varying injection rates and durations. The results of the CO2-charged brine injection showed that approximately 20 % of the injected CO2 circulates in the reservoir, ensuring reduced CO2 emissions. It has been estimated that 200 Mt of CO2 emission can be safely removed if all injection wells are used for NCG re-injection. © 2024
2024-01-01T00:00:00Z
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Evaluating ethanol concentrations against Staphylococcus spp: a proposal for improving nosocomial bacteria control
https://hdl.handle.net/11147/14341
Title: Evaluating ethanol concentrations against Staphylococcus spp: a proposal for improving nosocomial bacteria control
Authors: Soyer,F.; Ozdemir,O.O.; Polat,B.; Ekenel,N.H.
Abstract: [No abstract available]
2024-01-01T00:00:00Z
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Design, evaluation, and optimization of an integrated proton exchange membrane and double flash geothermal based organic Rankine cycle multi-generation system fed by a biomass-fueled gasifier
https://hdl.handle.net/11147/14339
Title: Design, evaluation, and optimization of an integrated proton exchange membrane and double flash geothermal based organic Rankine cycle multi-generation system fed by a biomass-fueled gasifier
Authors: Taheri,M.H.; Seker,U.; Akkurt,G.G.; Mohammadpourfard,M.
Abstract: This study introduces an innovative approach by formulating and evaluating a synergistic biomass-geothermal structure, emphasizing optimized inter-component connections. The research stands out for its thorough analysis of parameter impacts on the system and variables, addressing an unexplored aspect in integrated energy systems. The multi-generation systems are the integration of a combined gasification gas turbine cycle, double flash geothermal cycle, and proton exchange membrane cycle for the generating power and hydrogen. The overall system and its subsystems are studied to explore how the performance of thermodynamics and the total cost rate are influenced by operating parameters. The best operational conditions for both subsystems and the overall system have been determined by analyzing the impact of operating parameters on the thermodynamic behavior and environmental impact through parametric studies. The findings indicate while Sabalan's current efficiency is 16.26 %, the system energy efficiency reached 24.89 % when coupled with other renewable source. To enhance the system's efficiency, a genetics algorithm was utilized to simultaneously optimize the total cost of exergy destruction and investment cost. The outcome of the multi-objective optimization revealed that the exergy efficiency of optimal point for the system is 29.8 % and a total investment cost is 6 (M$/year). © 2023 Elsevier Ltd
2024-01-01T00:00:00Z