Scopus İndeksli Yayınlar Koleksiyonu / Scopus Indexed Publications Collection
Permanent URI for this collectionhttps://hdl.handle.net/11147/7148
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Article Nanoencapsulation of Hydroxytyrosol Extract of Fermented Olive Leaf Brine Using Proniosomes(Wiley, 2025) Kadiroglu, Pinar; Kilincli, Betul; Ilgaz, Ceren; Bayindir, Zerrin Sezgin; Kelebek, Hasim; Helvacioglu, Selin; Ozhan, GunesBACKGROUND: Olive leaves are rich in bioactive compounds with potential health benefits; however, their limited bioavailability and stability hinder their effective utilization. Emerging technologies, nanocarrier-based delivery systems, have shown promise in enhancing these properties. RESULTS: The optimal conditions for proniosome formulation were 50 rpm rotational speed and 35 degrees C, achieving 81.20 +/- 0.80% encapsulation efficiency. Particle sizes ranged from 188.6 to 248.9 nm, with a zeta potential of similar to-30 mV, indicating high stability and resistance to aggregation. Advanced instrumental analysis confirmed interactions between the extract and proniosome components. After 30 days at 4 degrees C, extract-loaded proniosomes maintained better homogeneity and lower polydispersity index. Cytotoxicity studies showed that both the extract and its proniosomal form were nontoxic to HEK293T cells up to 200 mu g mL(-1). In zebrafish assays, minimal larval mortality was observed up to 3200 mu g mL(-1) for the extract, while no mortality occurred up to 1600 mu g mL(-1) for the proniosomal extract, highlighting its improved safety profile. CONCLUSION: The findings from this research could contribute to the advancement of sustainable and health-promoting food innovations by integrating cutting-edge nanotechnology-driven encapsulation strategies into plant-based food formulations. (c) 2025 Society of Chemical Industry.Conference Object Citation - WoS: 1Citation - Scopus: 1Microstructural Evolution During Homogenization Heat Treatment of Aa 6063 Alloy in Batch and Continuous Furnaces(Springer international Publishing Ag, 2024) Obali, Akin; Gokelma, Mertol; Urk, Deniz Kavrar; Dogan, Murat; Gokce, GokcenHomogenization heat treatment after casting is performed to eliminate the dendritic segregation and coarse eutectic intermetallic phases since they reduce the fracture toughness of aluminium alloys. By the homogenization treatment, ss-AlFeSi can be converted to more spherical alpha-AlFeSi particles. The ss -> a transition is crucial because the ss-AlFeSi particles cause a number of surface defects and limit the extrudability. Also, the rate of cooling in the homogenization furnace is one of the critical influencing factors on the size of the Mg2Si precipitates which affect the mechanical properties positively. In this study, billets of AA 6063 from the same cast were put through homogenization heat treatment by using batch-type and continuous furnaces. The solution, quenching, and aging heat treatment were applied to each sample. Microstructural characterization by SEM and the hardness test were conducted to understand the effects of the furnace type on the mechanical properties of aged AA 6063 aluminium.Article Citation - Scopus: 1Characteristics and Production Technologies of Byzantine Building Bricks From the Anaia Church in Western Anatolia(Springer, 2023) Çam, Elif; Uğurlu Sağın, ElifFired bricks were valued as essential building materials in the central tradition of Byzantine architecture in Constantinople (Istanbul), Anatolia, and the Balkans. In this study, Byzantine bricks from three construction periods, covering nearly nine centuries (fifth-fourteenth centuries), of Anaia Church (Kadikalesi) in Western Anatolia were investigated to determine their characteristics, raw material properties, and production technologies. The characteristics of the bricks were evaluated and compared in order to identify similarities and differences between the periods and to investigate the continuity of the tradition of brick production over centuries. Basic physical and colorimetric properties, chemical and mineralogical compositions, thermal behavior, and microstructural and mechanical properties of bricks were determined by scanning electron microscopy (SEM) coupled with energy dispersive spectroscopy (SEM-EDS), Fourier-transform infrared spectrometry (FTIR), X-ray diffraction (XRD), thermogravimetric analysis (TGA), and mechanical tests. The results indicated that all the bricks in the Anaia Church were brown-beige colored, highly porous, low-density materials with low mechanical strength. They were produced from Ca-rich clays, probably obtained from two different sources used during all construction periods. The mineralogical composition and thermal properties revealed that the bricks from the first and second periods were fired at between 800 and 900 & DEG;C and the bricks from the third period were fired at < 850 & DEG;C. Greater calcium content and firing temperatures were found to reduce the total porosity and the number of small pores (< 10 & mu;m) and increase the mechanical strength of the bricks. The results of the study revealed no significant differences in the production of bricks, including raw material sources and kiln conditions, for the different construction periods of the church.Article Citation - Scopus: 3Characteristics of Byzantine-Period Lime Mortars and Plasters From the Anaia Church (kadikalesi)(Institute of Metals Technology, Ljubljana, 2022) Işık, Tuğçe; Uğurlu Sağın, ElifIn this study, Byzantine- period lime mortars and plasters used in the Anaia Church in Ku degrees adasy- Aydyn were examined in order to determine their characteristics and investigate the continuity of the lime mortar technology through centuries in the Anaia Church. The results will also contribute to future conservation studies at the site. Basic physical properties, raw-material compositions and hydraulic properties of lime mortars and plasters; mineralogical and chemical compositions, microstructural properties of binders, aggregates and limes; and pozzolanic activities of aggregates were determined using RILEM test methods, XRD, SEM-EDS and TGA. Mortar samples were comprised of natural aggregates whereas lime plasters were made of brick aggregates. Analyses revealed that plasters were slightly less dense and more porous than mortars due to the porous structure of the brick aggregates. All mortars and plasters were hydraulic due to the use of highly reactive pozzolanic aggregates. The basic physical properties, raw-material compositions, mineralogical and chemical compositions of mortars and plasters were found to be similar throughout the construction periods spread over different centuries. These similarities revealed the conscious knowledge of the lime mortar technology during the Byzantine period in Western Anatolia.Article Citation - WoS: 17Citation - Scopus: 22Protein Corona Formation on Silver Nanoparticles Under Different Conditions(Elsevier, 2022) Tomak, Aysel; Yılancıoğlu, Buket; Winkler, David; Öksel Karakuş, CeydaThe surfaces of nanoparticles become covered by biomolecules in biological fluids. This protein ‘corona’ modifies materials’ characteristics and biological activity. The composition of the protein corona is dynamic, abundant biomolecules that bind first are subsequently replaced by less abundant but more tightly bound ones. Here, we explore the formation of the silver nanoparticle protein corona on exposure to cell culture media containing 10 % fetal bovine serum supplemented Dulbecco's Modified Eagle's medium. Sodium dodecyl-sulfate polyacrylamide gel electrophoresis and liquid chromatography-mass spectrometry/mass spectrometry analysis were used to monitor how different parameters such as incubation time, heating duration, cell culture medium, incubation temperature, and the number of washes affect the nanoparticle–protein corona complex. silver nanoparticles with and without bound proteins were characterized by electron microscopy, dynamic light scattering, and ultraviolet-visible-near-IR spectroscopy. The tetrazolium-based MTT assay was used to determine viability of A549 human lung adenocarcinoma cells treated with silver nanoparticles. Characterization of the nanoparticles before and after protein binding provided insights into their changing morphology on corona formation. Our results confirmed that the physiological environment directly affects protein corona formation on nanoparticle surfaces. In particular, incubation condition-dependent differences in the amount of bound proteins were observed. This work highlights the importance of environmental drivers of protein adsorption, which should be considered when predicting and/or controlling protein targets of silver nanoparticles.Article Citation - Scopus: 1Enhancement of Cerium Exchange With Ultrasound(Turkish Chemical Society, 2018) Çakıcıoğlu Özkan, Fehime; Erten Kaya, YaseminIn this study the effect of ultrasound of the cerium exchange was studied. The results were compared to those obtained from traditional batch exchange method. Contact time, initial cation concentration (fold equivalent excess) and the types of the ultrasound were studied. Ultrasonic probe, which is the most effective method, enhanced the replacement of Na+ ion with Ce3+ ion in the extra-framework of zeolite up to 73 % by applying 5 consecutive ion exchanges. The cerium in the solution caused to be formed cerium oxides on the crystal surface occluding the pores. Thus the specific surface area of cerium exchanged zeolite was decreased due to formation of cerium complexes on the surface and into the pores. © 2018, Turkish Chemical Society. All rights reserved.Article Citation - WoS: 17Citation - Scopus: 20Preparation and Characterization of Antibacterial Cobalt-Exchanged Natural Zeolite/Poly(vinyl Alcohol) Hydrogels(Springer Verlag, 2014) Narin, Güler; Bulut Albayrak, Çisem; Ülkü, SemraIn the present study, potential application of the local clinoptilolite-rich natural zeolite in formulation of antibacterial hydrogels was investigated. The zeolite powder exchanged with cobalt(II) ions was used in preparation of the zeolite/poly(vinyl alcohol) hydrogel films in different amounts. The films were physically crosslinked by the freezing-thawing method and characterized for their crystallinity, surface and cross sectional morphology, chemical composition, thermal behaviour, mechanical properties, swelling and dissolution behaviours, and antibacterial activities against a Gram-negative bacteria. The films with 0.48 wt% and higher cobalt-exchanged zeolite contents showed antibacterial activity. Addition of the zeolite powder in the formulations did not cause significant changes in the other properties of the films.Article Citation - WoS: 3Citation - Scopus: 4Electrical Characterization of Interdigitated Humidity Sensors Based on Cnt Modified Calixarene Molecules(Polish Academy of Sciences, 2013) Özbek, Cebrail; Çulcular, Evren; Okur, Salih; Yılmaz, M.; Kurt, M.In this study, we report on the optimization and characterization of chloroform soluble calix[4]arene derivative as a humidity sensor based on electrical properties. Due to the fact that calix[4]arene molecules are nonconductive, we modified the calix[4]arene molecules with carbon nanotubes with electrostatic bond in order to increase the conductance of calix[4]arene molecule (5,11,17,23-tetra-ter-butyl-25,27-dehydrazinamidcarbonilmetoxy-26,28- -dehydroxy-kalix[4]aren). Using photolithography technique, we fabricated interdigitated gold electrodes with 3 micrometers separation to investigate the electrical properties of carbon nanotubes modified calix[4]arene molecule where we used dropcast method to form a thin film of carbon nanotubes modified calix[4]arene molecule on the gold electrodes. Our reproducible experimental results indicated that the chloroform soluble carbon nanotubes modified calix[4]arene films have great potential for humidity sensing applications at room temperature operations.Article Citation - WoS: 3Citation - Scopus: 4Electrical Characterizations of Schottky Diodes on Ito Modified by Aromatic Sams(Polish Academy of Sciences, 2013) Havare, A. Kemal; Okur, Salih; Yağmurcukardeş, Nesli; Can, M.; Aydın, H.; Şeker, M.; Demiç, ŞerafettinIn order to understand the electronic properties of the organic Schottky diode, ITO/TPD/Al and ITO/SAM/ TPD/Al organic Schottky devices were fabricated to obtain currentffvoltage characteristics. From the slopes and y-axis intercepts of the plots, the values of the ideality factor, barrier heights of the ITO/SAM/TPD/Al diode were determined as 2.03 and 0.56 eV, respectively. The surface characterizations of modified and unmodified ITO were performed via atomic force microscopy.Article Citation - WoS: 1Citation - Scopus: 1Improvement of Anode/Htl Interface Properties Using Self-Assembled Monolayer in Organic Electronic Devices(Polish Academy of Sciences, 2013) Yaman, M.; Yağmurcukardeş, Nesli; Havare, A. Kemal; Aydın, H.; Ocakoğlu, Kasım; Okur, SalihFabrication and characterization of highly effcient organic light-emitting diode with surface modification of indium tin oxide anodes by using self-assembled monolayer technique have been studied. Four different self-assembled molecules, K-28 ruthenium complex, octadecylamine hydrochloride, octadecyltrichlorosilane and mercaptohexdecanoic acid are used to modify ITO surface to improve the interface properties. Space charge limited currents measurements have been used to evaluate carrier mobility under steady state current. The results show that the surface properties such as the stability of ITO anode layer have significant effects on charge injection in organic light-emitting diode devices.