Scopus İndeksli Yayınlar Koleksiyonu / Scopus Indexed Publications Collection
Permanent URI for this collectionhttps://hdl.handle.net/11147/7148
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Article Citation - WoS: 1Citation - Scopus: 1Effect of Drying Method on Selected Physical and Functional Properties of Powdered Black Soldier Fly Larvae(Mdpi, 2025) Bogusz, Radoslaw; Nowacka, Malgorzata; Gondek, Ewa; Delman, Murat; Szulc, KarolinaThis research aimed to assay the impact of convective drying (CD) or infrared-convective (IR-CD) drying methods on the physical and techno-functional properties, FTIR spectra, and mathematical modeling of adsorption kinetics of black soldier fly larvae powders. By using convective drying, insect powder exhibited higher water content and water activity but lower hygroscopicity than powder dried with the infrared-convective method. After drying with the convective method, the powder exhibited a significantly lower loose and tapped bulk density and oil holding capacity (OHC). Furthermore, this powder was lighter and more yellow. The FTIR spectrum of the CD-dried powder showed lower absorption at key wavenumbers for the protein (1625 and 1350-1200 cm-1), indicating lower denaturation and less ability to bind water and water vapor. The mathematical modeling of the water vapor adsorption kinetics of insect powders via the second Fick's law for transient diffusion showed that this equation is suitable for adjusting the experimental data based on the high coefficient of determination (0.997-0.999) and the low root mean square (2.50-3.34%). This study revealed that the drying method influences insect powder properties, and the IR-CD method seems better in terms of obtaining better techno-functional properties.Article Citation - WoS: 34Citation - Scopus: 36Polymer derived ceramic aerogels(Pergamon-Elsevier Science Ltd, 2021) Ahmetoğlu, Çekdar Vakıf; Semerci, Tuğçe; Gurlo, Aleksander; Soraru, Gian DomenicoAerogels are unique porous solids having exceptional low relative density together with high specific surface area, making them very attractive materials for scientific research and industrial applications. Polymer derived ceramic aerogels are a new class of materials obtained through the pyrolysis of sol-gel/preceramic polymers. Herein this review, some of the representative formation methods and applications of polymer derived ceramic aerogels are highlighted with a specific focus on the thermal, electrical, and adsorbent related properties.Article Citation - WoS: 2Citation - Scopus: 2Morphology of Sodium Salt of Calf Thymus Dna on Mica, Alumina, and Silica Surfaces: Effect of Solvent and Drying Method(Taylor and Francis Ltd., 2017) Yetgin, Senem; Balköse, DevrimInvestigation of morphology of deoxyribonucleotide triphosphate (DNA) dried on different surfaces by atomic force microscopy (AFM) is important in DNA research that is focused on subjects of condensation for gene therapy, sizing, DNA mapping, and cancer examination. The solvent, the surface type, and the method of drying effect the morphology of DNA on solid surfaces. Ethanol and water were used as solvents, flat mica, silica, and alumina surfaces were used as the substrates in the present study. Different methods such as ambient air-drying, N2-forced flow regime drying, and freeze-drying have been applied to droplets of DNA solutions in water or ethanol on the substrates. Forced flow drying regime causes nonlinear DNA attachment on the surface and self-assembly. DNA vertical distance on mica surface was found to be 6 and 1.4 nm for DNA dried in ambient air from ethanol and water solutions, respectively. It was 1.6 nm for N2 flow drying of aqueous DNA solution on mica surface. It was 4.6, 4.6, and 1.99 nm for ambient, N2 flow, and freeze-dried aqueous DNA on alumina surfaces, respectively. Aqueous solution of DNA dried under N2 flow on silica surface had 0.8 nm vertical distance. The smallest standard deviation of 0.05 nm was observed for DNA dried under N2 flow on alumina surface.Article Citation - WoS: 27Citation - Scopus: 28An Exergetic Performance Assessment of Three Different Food Driers(SAGE Publications Inc., 2010) Hepbaşlı, Arif; Erbay, Zafer; Çolak, Neslihan; Hancıoğlu, Ebru; İçier, FilizIn this study, plum slices were dried in three different driers (tray, fluid bed, and heat pump (HP) driers). Drying experiments were carried out at an air temperature range of 45-55 °C with an air velocity of 1.5 m/s. The performance of the driers along with their main components was evaluated and compared by using the exergy analysis method. The most important component for improving the system efficiency was determined to be the fan-heater combination for both the tray and fluid bed driers, and the motor-compressor assembly for the HP drier. The exergy loss and flow diagram (the so-called Grassmann diagram) of the driers was also presented to give quantitative information regarding the proportion of the exergy input dissipated in the various system components. Effects of the drying air temperature on the performance of the drying process were discussed. The highest exergetic efficiency values were obtained to range from 72.72 to 75.66 per cent for the HP drier, followed by the tray and fluid bed driers varying between 37.94 and 39.46 per cent, and between 22.83 and 24.07 per cent, respectively.Article Citation - WoS: 71Citation - Scopus: 77A Comparative Study on Exergetic Performance Assessment for Drying of Broccoli Florets in Three Different Drying Systems(Taylor and Francis Ltd., 2010) İçier, Filiz; Çolak, Neslihan; Erbay, Zafer; Hancıoğlu Kuzgunkaya, Ebru; Hepbaşlı, ArifThis article deals with the exergy analysis and evaluation of broccoli in three different drying systems. The effects of drying air temperature on the exergy destruction, exergy efficiency, and exergetic improvement potential of the drying process were investigated. The exergy destruction rate for the drying chamber increased with the rise in the drying air temperature at 1.5 m/s, both in the tray and the heat pump dryer. The highest exergy efficiency value was obtained as 90.86% in the fluid bed dryer in comparison to the other two drying systems and the improvement potential rate was the highest in the heat pump dryer during drying of broccoli at the drying air temperature of 45°C and the drying air velocity of 1.0 m/s. © 2010 Taylor & Francis Group, LLC.Article Citation - WoS: 3Citation - Scopus: 4Exergy analysis of food drying processes(Springer Verlag, 2010) Çolak, Neslihan; Balta, Mustafa T.; İçier, Filiz; Hancıoğlu, Ebru; Hepbaşlı, Arif; Erbay, ZaferIt is well known that micro-level system parameters may have some great impact on macro-level energy aspects, the environment, and sustainability. Of course, if one wants to approach these thermodynamically, there are two ways: energy analysis through the first law of thermodynamics and exergy analysis through the second law of thermodynamics. Exergy analysis is an essential tool to expose the impacts of a power generating device on exergy-based sustainability; sustainability is necessary to overcome current ecological, economic, and developmental problems (Dincer and Rosen, 2005). In this regard, some new exergy-based sustainability parameters for a PEM fuel cell have been developed and studied parametrically to investigate how they will help measure the level of environmental impact and sustainable development (Midilli and Dincer, 2009). These types of parameters may also be applied to other energy-related systems.Article Citation - WoS: 30Citation - Scopus: 32Performance investigation of the drying of parsley in a tray dryer system(Inderscience Enterprises Ltd., 2010) Hancıoğlu, Ebru; Hepbaşlı, Arif; İçier, Filiz; Erbay, Zafer; Çolak, NeslihanThe performance of a tray dryer system for the parsley drying process was assessed using energy and exergy analysis methods in this study. The drying temperature ranged from 40°C to 60°C, while the drying air velocity varied from 0.5 m/s to 1.5 m/s. The higher temperature and lower velocity led to higher exergy and energy efficiencies. The exergy efficiency value for the overall system on a product/fuel basis was found to be 3.62%. The values for Specific Moisture Extraction Rate (SMER) and Specific Moisture Exergetic index (SMExR) were obtained to be 0.08 and 2.47 kg/kWh, respectively. Copyright © 2010 Inderscience Enterprises Ltd.Article Citation - WoS: 10Citation - Scopus: 10Multi-Zone Drying Schemes for Lowering the Residual Solvent Content During Multi-Component Drying of Semicrystalline Polymers(Taylor and Francis Ltd., 2007) Wong, Sim-Siong; Alsoy Altınkaya, Sacide; Mallapragada, Surya K.The development of a glassy skin in multicomponent semicrystalline polymer systems limits the diffusion of solvents out of the system and increases residual solvent levels. Based on the results of a mathematical model that we had previously developed, we have proposed a multi-zone drying scheme aimed at lowering the residual solvent levels by taking into account the effect of interactions between the various solvents as predicted by the model. This article focuses on the application of this model to develop optimal drying schemes and to verify the effectiveness of these predictions using experimental techniques. The mathematical model developed previously to study the diffusion of multiple solvents and changes in the crystallinity of semicrystalline polymer systems during drying incorporates many features including Vrentas-Duda diffusion theory, solvent-induced crystallization kinetics, as well as glass transition effects and skinning of the film. The multi-zone drying system was developed by varying the drying temperature in each zone as well as changing the partial pressure of individual solvents during the drying process. The effectiveness of the multi-zone drying schemes predicted by the model was validated experimentally using thermogravimetric methods. The polymer-solvent system chosen was a poly(vinyl alcohol)-water-methanol system. Our experimental data suggested that the multi-zone drying schemes were superior to a single-zone drying system through direct comparison. Further examination of the mathematical model yielded individual solvent profiles and these data reaffirmed our conclusions that a multi-zone drying scheme has the ability to reduce the effect of solvent trapping and thus lower the overall residual solvent content.Article Citation - WoS: 46Citation - Scopus: 48Drying of Semicrystalline Polymers: Mathematical Modeling and Experimental Characterization of Poly(vinyl Alcohol) Films(Elsevier Ltd., 2004) Wong, Sim-Siong; Alsoy Altınkaya, Sacide; Mallapragada, Surya K.A mathematical model was developed to predict the drying mechanism of semicrystalline polymers involving multiple solvents. Since drying of semicrystalline polymers can be accompanied by changes in polymer degree of crystallinity, the model integrates crystallization kinetics and the Vrentas-Duda diffusion model to provide a better understanding of the mechanism. The model considers the effect of external conditions such as temperature, film shrinkage and diffusion and evaporation of multiple solvents during drying. Poly(vinyl alcohol) (PVA)/water/methanol was chosen as a test system. The drying kinetics of PVA films swollen in water and methanol were investigated using gravimetric techniques. The model predicts that higher temperatures, lower film thicknesses and lower methanol to water ratios increase the drying rate. The model predictions were compared with experimental data and showed good agreement.Article Citation - WoS: 22Citation - Scopus: 22Onsager consistency checks for multicomponent diffusion models(John Wiley and Sons Inc., 2001) Zielinski, John M.; Alsoy Altınkaya, SacideThe Onsager reciprocity relations are applied to several recently proposed multicomponent diffusion models in an attempt to gauge their validity and ascertain their applicability. Each of these friction-based diffusion models stems from the more general Bearman formalism through various assumptions regarding the individual friction coefficients. By assessing the compliance of the Bearman model with respect to the Onsager relations, we ascertain the validity of the simplifications introduced to each diffusion model and suggest which postulates lead to results consistent with the Onsager relations. Although some models are not consistent with the Onsager relations, each model predicts the multicomponent drying of polymer films reasonably well. The necessity for consistency with the Onsager development is, therefore, revisited.