Chemical Engineering / Kimya Mühendisliği

Permanent URI for this collectionhttps://hdl.handle.net/11147/14

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  • Conference Object
    Citation - WoS: 24
    Effect of pH and Hydration on the Normal and Lateral Interaction Forces Between Alumina Surfaces
    (2006) Polat, Mehmet; Sato, Kimiyasu; Nagaoka, Takaaki; Watari, Koji
    Normal 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
  • Article
    Citation - WoS: 5
    Citation - Scopus: 5
    Automated Deep Learning Model Development Based on Weight Sensitivity and Model Selection Statistics
    (Pergamon-elsevier Science Ltd, 2025) Yalcin, Damla; Deliismail, Ozgun; Tuncer, Basak; Boy, Onur Can; Bayar, Ibrahim; Kayar, Gizem; Sildir, Hasan
    Current sustainable production and consumption processes call for technological integration with the realm of computational modeling especially in the form of sophisticated data-driven architectures. Advanced mathematical formulations are essential for deep learning approach to account for revealing patterns under nonlinear and complex interactions to enable better prediction capabilities for subsequent optimization and control tasks. Bayesian Information Criterion and Akaike Information Criterion are introduced as additional constraints to a mixed-integer training problem which employs a parameter sensitivity related objective function, unlike traditional methods which minimize the training error under fixed architecture. The resulting comprehensive optimization formulation is flexible as a simultaneous approach is introduced through algorithmic differentiation to benefit from advanced solvers to handle computational challenges and theoretical issues. Proposed formulation delivers 40% reduction, in architecture with high accuracy. The performance of the approach is compared to fully connected traditional methods on two different case studies from large scale chemical plants.
  • Article
    Citation - WoS: 1
    Citation - Scopus: 1
    Optimized Lithium(I) Recovery From Geothermal Brine of Germencik, Türkiye, Utilizing an Aminomethyl Phosphonic Acid Chelating Resin
    (Taylor and Francis Ltd., 2025) Recepoğlu, Y.K.
    This study investigates the performance of Lewatit TP 260 ion exchange resin for the efficient recovery of lithium (Li(I)) from geothermal water sourced from the Germencik Geothermal Power Plant in Türkiye. A series of batch sorption experiments were performed to evaluate the influence of key parameters, including resin dosage, solution pH, temperature, initial Li(I) concentration, and contact time, on the Li(I) recovery process. The optimal conditions were determined to be a resin dose of 0.5 g per 25 mL of geothermal water, pH in the range of 6–8, and a temperature of 25°C. Under these conditions, the resin achieved a maximum Li(I) recovery rate of 71% from the geothermal water. Sorption isotherms were further analyzed using the Langmuir, Freundlich, and Dubinin-Radushkevich (D-R) models. Among these, the Langmuir model provided the best fit (R² = 0.9841), suggesting a maximum sorption capacity (qm) of 4.31 mg/g. Continuous recovery experiments conducted in column mode confirmed the practical applicability of Lewatit TP 260, achieving a total sorption capacity of 0.41 mg Li(I)/mL resin. The findings exhibit the potential of this resin as a viable sorbent for sustainable Li(I) extraction from geothermal brines, supporting the development of green energy technologies and contributing to the circular economy. © 2024 Taylor & Francis Group, LLC.
  • Correction
    Citation - WoS: 1
    Erratum: 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: 6
    Citation - Scopus: 6
    Synthesis of a Novel Cellulose-Based Adsorbent From Olive Tree Pruning Waste for Removal of Boron From Aqueous Solution
    (Springer Science and Business Media Deutschland GmbH, 2024) Altınbaş, B.F.; Yüksel, A.
    This work investigated the valorization of olive tree pruning debris as a biosorbent for the removal of environmentally hazardous boron from aqueous solution using batch adsorption. For this purpose, a novel, waste-based, boron selective biosorbent from olive tree pruning waste (N-OPW) was synthesized. Alkali pretreatment, followed by glycidyl-methacrylate (GMA) grafting and providing boron selectivity with n-methyl-d-glucamine (NMDG) steps, was applied to the biomass, respectively. N-OPW was characterized using SEM, TGA, and FT-IR analyses. N-OPW showed excellent boron biosorption capacity (21.80 mg/g) in an operation pH range between 2 and 12. The equilibrium was attained in 2 h and the Freundlich isotherm (R2 = 0.997) and pseudo-second-order kinetics (R2 = 0.99) provided the strongest match to experimental data. According to thermodynamic studies, boron adsorption was exothermic (ΔH = −34.14 kJ/mol). The reusability tests with real geothermal water showed that adsorbent had no significant decrease in boron removal capacity while desorbing >99% of the boron adsorbed for three cycles of adsorption/desorption. Results indicated that a promising, reusable, and boron selective biosorbent was successfully synthesized while utilizing olive pruning waste. Graphical abstract: (Figure presented.) © The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature 2023.
  • Book
    Citation - Scopus: 5
    Aluminium-Coated Polymer Films as Infrared Light Shields for Food Packing
    (Apple Academic Press, 2014) Hamrang, Abbas; Balköse, Devrim; Zaikov, Gennadij Efremovich; Haghi, A. K.
    This book covers a broad range of polymeric materials and provides industry professionals and researchers in polymer science and technology with a single, comprehensive book summarizing all aspects involved in the functional materials production chain. This volume presents the latest developments and trends in advanced polymer materials and structures. It discusses the developments of advanced polymers and respective tools to characterize and predict the material properties and behavior. This book has an important role in advancing polymer materials in macro and nanoscale. Its aim is to provide original, theoretical, and important experimental results that use non-routine methodologies. It also includes chapters on novel applications of more familiar experimental techniques and analyses of composite problems that indicate the need for new experimental approaches. This new book: • Provides a collection of articles that highlight some important areas of current interest in key polymeric materials and technology. • Gives an up-to-date and thorough exposition of the present state of the art of key polymeric materials and technology. • Describes the types of techniques now available to the engineers and technicians and discusses their capabilities, limitations, and applications. • Provides a balance between materials science and chemical aspects, basic and applied research. • Focuses on topics with more advanced methods. • Emphasizes precise mathematical development and actual experimental details. • Explains modification methods for changing of different materials properties. © 2020 Elsevier B.V., All rights reserved.
  • Article
    Citation - WoS: 29
    Citation - Scopus: 35
    Sustainable Bio-Nano Composite Coatings for the Protection of Marble Surfaces
    (Elsevier Masson SAS, 2015) Ocak, Y.; Sofuoglu, A.; Tihminlioglu, F.; Böke, H.
    Water repellency on natural stone surfaces is the most important issue in the protection of stone monuments from effects of atmospheric pollutants. In this study, effectiveness of a bio-nano composite coating, composed of a biodegradable polymer (poly-L-lactide [PLA]) and montmorillonite clay (MMT) was investigated for the protection of marble surfaces from pollution. The clay dispersion in polymer matrices was analyzed by using Scanning Tunnel Electron Microscopy (STEM) and X-Ray Diffraction (XRD), while protection performance was investigated by the measurement of surface roughness, wettability, water vapor permeability, capillary water absorption, and color changes on the marble surfaces. As a result, no alteration on the color of coated marbles was observed, significant improvement was obtained for hydrophobicity of the surface and inhibition of sulfation reaction on the exposed marble surfaces under acidic atmosphere. It could be said that PLA based nanocomposites seem to be promising materials as protective coating agents in reducing the effects of water and atmospheric pollutants on marble surfaces. © 2014 Elsevier Masson SAS.
  • Article
    Citation - WoS: 35
    Citation - Scopus: 40
    Olive Leaf Extract as a Crosslinking Agent for the Preparation of Electrospun Zein Fibers
    (John Wiley and Sons Inc., 2015) Erdogan, I.; Demir, M.; Bayraktar, O.
    Incorporating active agents, reinforcing structure by crosslinking, thus changing release properties, can be listed as possible modifications in preparation methods of biopolymer fibers. This study introduces oleuropein, major component of olive leaf extract (OLE), as a natural functional crosslinker for electrospun zein fibers, owing to its antioxidant and antimicrobial properties. Incorporation of OLE causes morphological and structural changes indicated by a decrease in fiber diameter up to 27%, an increase in intensity of NH bending region due to interaction with -OH groups and observation of characteristic oleuropein bands. Extract addition also enhances thermal stability. Zein fibers without OLE is fully degraded at 600C, whereas 10% of OLE loaded zein fibers is left undegraded. Fifty percent of initial phenolic content loaded into fibers is released which indicate the effect of OLE incorporation as accumulation of oleuropein. OLE-incorporated fibers immersed in PBS are less fused than pure zein fibers, due to the crosslinking effect. © 2014 Wiley Periodicals, Inc.