Browsing by Author "Pekcan, Önder"
Now showing items 81-100 of 101
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Sorption and Desorption of PVA-Pyrene Chains in and out of Agarose Gel
Kara, Selim; Gacal, Burçin; Tunç, Deniz; Yağcı, Yusuf; Pekcan, Önder (Springer/Plenum Publishers, 2012)In situ steady-state fluorescence (SSF) measurement technique was applied to investigation of pyrene labeled Poly(vinyl alcohol) (PVA-Py) molecules diffusion in and out of agarose gels. Gel samples with four different ... -
Spectroscopic study of film formation from polystyrene latex/TiO2 nanocomposites prepared by dip-coating method
Sunay, M. Selin; Pekcan, Önder; Rahman, Md. Mahbubor; Elaissari, Abdelhamid; Ugur, Saziye (Wiley-Blackwell, 2014)In this study we investigated the influence of TiO2 content and thickness of polystyrene (PS) template on film-formation behavior of PS/TiO2 composites using fluorescence and ultraviolet-visible techniques in conjunction ... -
Steady state fluorescence technique for studying phase transitions in PAAm-PNIPA mixture
Evingür, Gülşen Akın; Aktaş, Demet Kaya; Pekcan, Önder (Taylor & Francis, 2009)The steady state fluorescence (SSF) technique was used to study the sol-gel phase transition during free radical crosslinking copolymerisation of various amounts of acrylamide (AAm) and N-isopropylacrylamide (NIPA) mixtures. ... -
Structural Analysis of Peptide Fragments Following The Hydrolysis of Bovine Serum Albumin by Trypsin and Chymotrypsin
Özyiğit, İbrahim Ethem; Akten, Ebru Demet; Pekcan, Önder (Taylor & Francis Inc, 2016)Peptide bond hydrolysis of bovine serum albumin (BSA) by chymotrypsin and trypsin was investigated by employing time-resolved fluorescence spectroscopy. As a fluorescent cross-linking reagent N-(1-pyrenyl) maleimide (PM) ... -
Studies on Drying and Swelling of PAAm-NIPA Composites in Various Compositions
Evingür, Gülşen Akin; Pekcan, Önder (Wiley-Blackwell, 2011)The steady-state fluorescence technique was introduced for studying the drying and swelling of disc-shaped PAAm-NIPA composites. Disc-shaped gels were formed with various acrylamides (AAm) and N-isopropylacrylamides (NIPA) ... -
Study of Film Formation From PS Latex/TiO2 Nanocomposites
Uğur, Saziye; Sunay, M. Selin; Pekcan, Önder (Wiley-Blackwell, 2014)In this work we investigated the film formation from polystyrene (PS) latex/TiO2 nanocomposites using the steady state fluorescence (SSF) and UV-vis (UVV) techniques depending on PS particle size and TiO2 content. The ... -
Study of Thermal Phase Transitions in Iota Carrageenan Gels via Fluorescence Technique
Tari, Ozlem; Kara, Selim; Pekcan, Önder (Wiley-Blackwell, 2011)The effect of carrageenan concentration on thermal phase transitions of the iota carrageenan gels was investigated by using fluorescence technique. During heating and cooling processes scattered light I(sc) and fluorescence ... -
Superelastic percolation network of polyacrylamide (PAAm)-kappa carrageenan (kappa C) composite
Evingür, Gülşen Akin; Pekcan, Önder (Springer, 2013)The elasticity of the polyacrylamide (PAAm)-kappa carrageenan (kappa C) composite was determined as a function of (w/v-%) kappa C content at 40 A degrees C. The gel composites studied contained various percentages (w/v-%) ... -
Surfactant and Metal Ion Effects on the Mechanical Properties of Alginate Hydrogels
Kaygusuz, Hakan; Evingür, Gülşen Akin; Pekcan, Önder; von Klitzing, Regine; Erim, F. Bedia (Elsevier Science Bv, 2016)This paper addresses the controlled variation of the mechanical properties of alginate gel beads by changing the alginate concentration or by adding different surfactants or cross-linking cations. Alginate beads containing ... -
Surfactant-free one-step fabrication of gelatin/PAAm/MWCNT composites for biomedical applications
Duzkan, Berke; Uysal, Bengü Özuğur; Pekcan, Önder (Springer, 2021)Well-dispersed multiwalled carbon nanotube (MWCNT) and gelatin-enhanced polyacrylamide (PAAm) composites were synthesized via a free-radical copolymerization method. MWCNTs were added to the composite mixture in various ... -
Swelling Kinetics of PAAm-kappa-Carrageenan Composites: A Fluorescence Technique
Evingür, Gülşen Akın; Pekcan, Önder (Taylor & Francis Inc, 2011)The steady-state fluorescence (SSF) technique was introduced for studying swelling of disc-shaped polyacrylamide (PAAm) gels containing various amount of kappa-carrageenan (kappa C). They were prepared by free-radical ... -
Tailoring The Electrical and Optical Properties of Carbon Nanotube Reinforced Transparent Tio 2 Composites by Varying Nanotube Concentrations
Uysal, Bengü Özuğur; Akkaya Arier, Ümit Özlem; Pekcan, Önder (World Scientific Publ Co Pte Ltd, 2019)In the present work multi-walled carbon nanotube (MWCNT)-doped TiO 2 nanocomposite films were synthesized by sol-gel method. The influence of nanotube concentration on the structural electrical and optical properties of ... -
Temperature Dependence of Oxygen Diffusion into Clay-Doped PS Films
Uğur, Şaziye; Yargı, Önder; Pekcan, Önder (John Wiley & Sons Inc, 2010)Fluorescence technique was employed for the measurement of the diffusion coefficient of oxygen into polystyrene (PS) latex/modified Na-activated bentonite (MNaLB) clay composite films. Three different MNaLB content (0 5 ... -
Temperature dependence of oxygen diffusion into polymer/carbon nanotube composite films
Yargı, Önder; Uğur, Şaziye; Pekcan, Önder (Wiley-Blackwell, 2012)This study examines the transport properties of polystyrene (PS)/multiwalled carbon nanotube (MWNT) composite films taking into consideration both MWNT composition and temperature via fluorescence technique. Three different ... -
Temperature Effect on the Elasticity of Acrylamide-n-Isopropylacrylamide Copolymers
Evingür, Gülşen Akin; Pekcan, Önder (Taylor & Francis Inc, 2018)Acrylamide (AAm) - N-isopropylacrylamide (NIPA) copolymers were prepared via free radical crosslinking copolymerization with various weight percentages (wt%) of AAm and NIPA. The temperature dependence of the compressive ... -
Temperature effect on the swelling of PAAm-kappa-carrageenan composites
Evingür, Gülşen Akin; Pekcan, Önder (Wiley-Blackwell, 2012)The steady-state fluorescence (SSF) technique was used for studying swelling of disc-shaped polyacrylamide (PAAm)-kappa-carrageenan (kappa C) composites which were prepared by free-radical crosslinking copolymerization at ... -
Thermal Phase Transitions of Agarose in Various Compositions: A Fluorescence Study
Kara, Selim; Arda, Ertan; Dolastir, Fahrettin; Pekcan, Önder (Springer/Plenum Publishers, 2011)The effect of agarose content on thermal phase transitions of the agarose gels was investigated by using Steady State Fluorescence (SSF) method. Scattered light I(sc) and fluorescence intensity I(fl) were monitored against ... -
Thermal Phase Transitions of IOTA Carrageenan in CaCl2 Solutions: A Fluorescence Study
Tari, Ozlem; Kara, Selim; Pekcan, Önder (Taylor & Francis Inc, 2011)The fluorescence technique was employed to study thermal phase transitions of iota (-) carrageenan (IC) in CaCl2 solution. IC gels underwent coil to double helix (c-h) and double helix to dimer (h-d) transitions upon ... -
Universality in gelation of epoxy acrylate with various photoinitiators: a photo differential scanning calorimetric study
Doğruyol, Zekeriya; Karasu, Feyza; Balta, Demet Karaca; Arsu, Nergis; Pekcan, Önder (Taylor & Francis Ltd, 2008)Photo-differential scanning calorimetric (Photo-DSC) technique was used to study the gelation of P-3038 (epoxy acrylate (EA) 75% and tripropyleneglycoldiacrylate (TPGDA) 25%) in the presence of various thioxanthone-based ... -
Universality of elasticity on PAAM-NIPA copolymer gels
Evingür, Gülşen Akin; Pekcan, Önder (EDP Sciences, 2015)Polyacrylamide (PAAm)-N-isopropylacrylamide (NIPA) copolymers were prepared via free radical crosslinking copolymerization with different molar of NIPA varying in the range between 0 and 2 M. The mechanical properties of ...