Chemical Engineering / Kimya Mühendisliği
Permanent URI for this collectionhttps://hdl.handle.net/11147/14
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Conference Object Citation - WoS: 24Effect of pH and Hydration on the Normal and Lateral Interaction Forces Between Alumina Surfaces(2006) Polat, Mehmet; Sato, Kimiyasu; Nagaoka, Takaaki; Watari, KojiNormal and lateral interaction forces between alumina surfaces were measured using Atomic Force Microscopy-Colloid Probe Method at different pH. The normal force curves exhibit a well-defined repulsive barrier and an attractive minimum at acidic pH and the DLVO theory shows excellent agreement with the data. The normal forces are always repulsive at basic pH and the theory fails to represent the measurements. Lateral forces are almost an order of magnitude smaller in the basic solutions. These differences, which have important implications in the study of stability and rheology, are attributed to the hydration of the alumina surface at basic pH. © 2013 Elsevier B.V., All rights reserved.Conference Object Hydrogen Production From Sugar Beet Wastewater in the Presence of Perovskite Type Catalysts by Photocatalysis(Amer Chemical Soc, 2019) Ozsen, Asli Yuksel; Orak, CerenCorrection Citation - WoS: 1Erratum: Bioactive Snail Mucus-Slime Extract Loaded Chitosan Scaffolds for Hard Tissue Regeneration: the Effect of Mucoadhesive and Antibacterial Extracts on Physical Characteristics and Bioactivity of Chitosan Matrix (Biomedical Materials (Bristol) (2021) 16 (065008) Doi: 10.1088/1748-605x(IOP Publishing, 2023) Perpelek, M.; Tamburaci, S.; Aydemi̇r, S.; Tıhmınlıoğlu, F.; Baykara, B.; Karakaşli, A.; Havitçioǧlu, H.The authors regret that some errors were identified in 'figures 12 and 13' on pages 14 and 15, in the published manuscript concerning fluorescence microscopy images of Saos-2 and SW1353 cells on scaffolds for 1 and 3 d of incubation. The fluorescence images in figures 12 and 13 were mistakenly used as duplicated due to the inadvertently mislabeling during the processing of files and integrating them into the final figures. Intensity data regarding corrected fluorescence images were also measured and corrected. The revised figures (figures 12 and 13) and their captions appear below. The authors apologize for this error and state that this does not change the scientific conclusions of the article in any way. (Figure Presented). © 2023 IOP Publishing Ltd.Article Citation - WoS: 9Citation - Scopus: 10Investigation of Reactive Extraction of Monocarboxylic Acids With Menthol-Based Hydrophobic Deep Eutectic Solvent by Response Surface Methodology(Taylor & Francis Inc, 2023) Yıldız, Esra; Lalikoğlu, Melisa; Aşçı, Yavuz Selim; Sırma Tarım, BurcuThe growing demand for producing organic acids by fermentative techniques has increased the significance of separating carboxylic acids from their fermentation broth with the reactive extraction process. Considering the environmental impacts, deep eutectic solvents can be considered as a potential green alternative for the replacement of volatile organic solvents commonly used in the extraction process. In this study, a new type of green solvent named hydrophobic deep eutectic solvent (HDES) based on decanoic acid as a hydrogen bond acceptor and menthol as a hydrogen bond donor was utilized for the reactive extraction of formic, acetic, and propionic acids from their aqueous solutions. The effect of initial acid concentration, HDES molar ratio, and tri-n-octyl amine (TOA) concentration on extraction efficiency was investigated. Modeling of the reactive extraction process was performed via a response surface methodology with a central composite design. Herein, the effect of the parameters of TOA concentration, HDES molar ratio, and initial acid concentration on the distribution coefficient was investigated. According to the results, it was reported that the most effective parameter on the extraction efficiency (%E) was the amount of extractant. The results of the experimental studies showed that the highest separation efficiency was obtained for 5% initial concentrations of formic, acetic, and propionic acids by using a mixture of 0.5 HDES molar ratio solvent and 1.9 mol/L TOA. The extraction efficiencies of these acids were found to be 88.71, 92.52, and 95.90 with +/- 0.1 standard deviation, respectively.Article Citation - WoS: 3Citation - Scopus: 4Photocatalytic and Optical Properties of Zinc Oxide Structures Prepared at Different Urea Concentrations(Serban Solacolu Foundation, 2020) Uysal, Berk; Şen, Selin; Top, AybenIn this study, ZnO samples were synthesized using zinc acetate and urea with a method containing sonication, sol-gel transition and calcination steps. Urea to zinc acetate mole ratio values were changed as 0, 0.5, 1, and 2 and corresponding calcined samples were denoted as UZ-0, UZ-0.5, UZ-1, and UZ-2, respectively. Scanning electron microscopy (SEM) images indicated globular and rod-like structures. Aspect ratios of the nanorods increased as urea to zinc acetate ratio increased from 0 to 1 whereas nanoparticles with sizes of 70 +/- 20 nm were observed for UZ-2 sample. Brunauer, Emmett and Teller (BET) surface area values of the samples varied between 9 and 25 m(2)/g and increased as initial urea amount increased. Band gap energies of the samples ranged between 3.24 and 3.29 eV. Four major peaks at about 400, 420, 480 and 530 nm with different intensities were observed in the photoluminescence (PL) spectra of the samples. All the samples removed rhodamine B by both adsorption and photodegradation. The highest visible light induced photodegradation rate was exhibited by UZ-2 sample having the highest surface area and it is attributed to superior charge separation properties of this sample under visible light.Conference Object Effect of Some Physical, and Chemical Variables on Flocculation and Sediment Behaviour(A.A. Balkema Publishers, 2000) Polat, Hürriyet; Polat, Mehmet; İpekoğlu, ÜnerEffect of some chemical and physical variables on the settling rate, final sediment height, sediment viscosity and supernatant turbidity of a clay sample was studied using various polyacrylamide type flocculants. Increasing flocculant concentration significantly increased both the settling rate and sediment viscosity. More importantly, changes in the final sediment, height, hence the packing density, was minimal for all the conditions tested once the sediment was allowed to consolidate. Also, the mode of addition of the polymer, at once or continuous, did not seem to affect any of the parameters measured. Conditioning time seemed to alter the settling rate at low polymer concentrations, but had no effect at high polymer concentrations. However, increasing the conditioning time caused a decrease in the sediment viscosity. Different types of the polyacrylimides generated different settling rates at a given concentration, but the final sediment height was nearly independent of polymer type.Conference Object Predicting Drying in Solvent-Coated Polymeric Films(American Chemical Society, 2000) Alsoy Altınkaya, Sacide; Duda, John Larry[No abstract available]Conference Object Fret based pattern recognition of isogenic cells differing in cell surface glycans(American Chemical Society, 2010) Miranda, Oscar R.; Bajaj, Avinash; Elçi, Şükrü Gökhan; Rana, Subinoy; Saha, Krishnendu; Phillips, Ronnie L.; Rotello, Vincent M.[No abstract available]Conference Object Raft-Synthesis of Cholesterol Conjugated Polymers as Potential Therapeutic Carriers(American Chemical Society, 2011) Sevimli, Sema; İnci, Fatih; Bulmuş, Volga[No abstract available]Conference Object Acid-Catalyzed Degradation of Biomass With Hydrothermal Electrolysis for the Production of Value-Added Chemicals(American Chemical Society, 2014) Yüksel, Aslı; Yüksel Özşen, Aslı[No abstract available]