Yazar "Gubbuk, Ilkay Hilal" seçeneğine göre listele

Listeleniyor 1 - 7 / 7
  • Küçük Resim Yok
    Öğe
    Adsorptive removal of Co(II), Ni(II), and Cu(II) ions from aqueous media using chemically modified sporopollenin of Lycopodium clavatum as novel biosorbent
    (DESALINATION PUBL, 2014) Cimen, Aysel; Bilgic, Ali; Kursunlu, Ahmed Nuri; Gubbuk, Ilkay Hilal; Ucan, Halil Ismet
    In this study, sporopollenin of Lycopodium clavatum spores was used for sorption experiments. (E)-4-((2-hydroxyphenylimino) methyl) benzoic acid (HPBA) immobilized sporopollenin (Sp) was employed as a sorbent in sorption of selected heavy metal ions in aqueous solutions. The sorbent material was prepared with sequential treatment of sporopollenin with silanazing compound and HPBA. Experimental conditions for effective sorption of heavy metal ions were optimized with respect to different experimental parameters using the batch method in detail. pHs for maximum sorption of Cu(II) Ni(II) and Co(II) ions were found in six and five, respectively. Langmuir, Freundlich, and Dubinin-Radushkevich (D-R) isotherm equations were applied to the experimental data. Thermodynamic parameters such as free energy (Delta G degrees), entropy (Delta S degrees), and enthalpy (Delta H degrees) were also calculated from the sorption results and were used to explain the mechanism of the sorption. The results indicated that this sorbent is successfully employed in the separation of trace Cu(II), Ni(II), and Co(II) from the aqueous solutions.
  • Küçük Resim Yok
    Öğe
    Chemical modification of silica gel with synthesized new Schiff base derivatives and sorption studies of cobalt (II) and nickel (II)
    (ELSEVIER SCIENCE BV, 2009) Kursunlu, Ahmed Nuri; Guler, Ersin; Dumrul, Hakan; Kocyigit, Ozcan; Gubbuk, Ilkay Hilal
    In this study, three Schiff base ligands and their complexes were synthesized and characterized by infrared spectroscopy (IR), thermogravimetric analyses (TGA), nuclear magnetic resonance (NMR), elemental analysis and magnetic susceptibility apparatuses. Silica gel was respectively modified with Schiff base derivatives, (E)-2-[(2-chloroethylimino)methyl]phenol, (E)-4-[(2-chloroethylimino) methyl]phenol and N,N'-[1,4-phenilendi(E)methylidene]bis(2-chloroethanamine), after silanization of silica gel by (3-aminopropyl)trimethoxysilane (APTS) by using a suitable method. Characterization of the surface modi. cation was also performed with IR, TGA and elemental analysis. The immobilized surfaces were used for Co(II) and Ni(II) sorption from aqueous solutions and values of sorption were detected by atomic absorption spectrometer (AAS). (C) 2009 Elsevier B.V. All rights reserved.
  • Küçük Resim Yok
    Öğe
    Isotherms and thermodynamics for the sorption of heavy metal ions onto functionalized sporopollenin
    (ELSEVIER, 2011) Gubbuk, Ilkay Hilal
    In this study, sporopollenin of Lycopodium clavatum spores was used for the sorption experiment. Glutaraldehyde (GA) immobilized sporopollenin (Sp), is employed as a sorbent in sorption of selected heavy metal ions. The sorbent prepared by sequential treatment of sporopollenin by silanazing compound and glutaraldehyde is suggested for sorption of Cu(ll), Zn(II) and Co(II) from aqueous solutions. Experimental conditions for effective sorption of heavy metal ions were optimized with respect to different experimental parameters using batch method in detail. Optimum pH range of Cu(II) has occurred at pH >= 5.5 and Zn(II), Co(II) at pH >= 5.0. for the batch method. All of the metal ions can be desorbed with 10 cm(3) of 0.5 mol dm(-3) of ethylenediaminetetraacetic acid (EDTA) solution. Langmuir, Freundlich and Dubinin-Radushkevich (D-R) isotherm equations were applied to the experimental data. Thermodynamic parameters such as free energy (Delta G degrees), entropy (Delta S degrees) and enthalpy (Delta H degrees) were also calculated from the sorption results used to explain the mechanism of the sorption. The results indicated that this sorbent is successfully employed in the separation of trace Cu(ll), Zn(II) and Co(II) from the aqueous solutions. (c) 2010 Elsevier B.V. All rights reserved.
  • Küçük Resim Yok
    Öğe
    Sorption of heavy metal ions by glass beads-immobilized calix[4]arenes derivative
    (MAIK NAUKA/INTERPERIODICA/SPRINGER, 2013) Gubbuk, Ilkay Hilal; Ozkan, Seyda Cigdem; Yilmaz, Aydan
    Glass beads (GB) immobilized, 5,11,17,23-tetra-tert-butyl-25,27-diethoxycarbonylmethoxy-26,28-dihydroxycalix[4]arene (CA) are prepared and used as a new sorbent in sorption study of removal heavy metal ions. A calixarene derivative bonded to amino-functionalized glass beads sorbent was synthesized via a self assembly technique for sorbent of selected heavy metal ions in aqueous. In order to absorb selected heavy metal ions in aqueous, a calixarene derivative bonded to amino-functionalized glass beads sorbent was synthesized via a self assembly technique. The sorbent which is named GB-APTS-CA was characterized using infrared (FTIR) spectroscopy, scanning electron microscopy (SEM), elemental analysis and thermal analysis (TGA/DTG). The influences of some experimental parameters including pH of the sample solution, weight of sorbent, concentration and temperature have been investigated. The sorption data were evaluated using the Langmuir, Freundlich and Dubinin Radushkevich (D-R) isotherm. The obtained maximum sorption capacity for Cu(II), and Pb(II) is 0.06 mmol g(-1) and 0.02 mmol g(-1), respectively. Thermodynamic parameters such as the standard free energy change (Delta Gau <), enthalpy change (Delta Hau <) and entropy change (Delta Sau <) were calculated to determine the nature of sorption process. Thus, GB-APTS-CA is favorable and useful for the removal of Cu(II) and Pb(II) metal ions.
  • Küçük Resim Yok
    Öğe
    Thermal Degradation Behaviour of Ni(II) Complex of 3,4-Methylenedioxaphenylaminoglyoxime
    (HINDAWI PUBLISHING CORPORATION, 2013) Karapinar, Emin; Gubbuk, Ilkay Hilal; Taner, Bilge; Deveci, Pervin; Ozcan, Emine
    Thermal degradation behaviour of the Ni(II) complex of 3,4-methylenedioxaphenylaminoglyoxime was investigated by TG, DTA, and DTG at a heating rate of 10 degrees C min(-1) under dinitrogen. The acquired experimental data shows that the complex is thermally stable up to 541 K. The pyrolytic decomposition process occurs by melting metal complex and metal oxide remains as final product. The energies of the reactions involved and the mechanism of decomposition at each stage have been examined. The values of kinetic parameters such as activation energy (E), preexponential factor (A) and thermodynamic parameters such as enthalpy (Delta H), entropy (Delta S), and Gibbs free energy (Delta G) are also evaluated.
  • Küçük Resim Yok
    Öğe
    Transport of methylene blue through bulk liquid membrane containing calix[8]arene derivative
    (DESALINATION PUBL, 2014) Gubbuk, Ilkay Hilal; Gungor, Omer
    In this study, an experimental study on the transport of methylene blue ( MB) through bulk liquid membrane ( BLM) is done and thereby best set of solvent, operating conditions, and mode of transport that would yield optimum performance of the BLM are identified. Therefore, a kinetic study of MB transport from an aqueous donor phase into an aqueous acceptor phase through a BLM containing calix[8] arene octacarboxylic acid ( COCA) derivative as a carrier was studied. The influence of type of solvent, stirring speed, effect of NaCl weight in feed phase and temperature were investigated. The kinetic parameters ( k(1), k(2), R-m(max), t(max), J(d)(max), J(a)(max)) were calculated for the interface reactions assuming two consecutive, irreversible first-order reactions. In this study, the experiments demonstrated that COCA derivative is a good carrier for MB transport through liquid membranes.
  • Küçük Resim Yok
    Öğe
    Universal cell capture by immobilized antimicrobial peptide plantaricin
    (ELSEVIER SCIENCE BV, 2015) Guralp, Saadet Albayrak; Gubbuk, Ilkay Hilal; Kucukkolbasi, Semahat; Gulari, Erdogan
    Plantaricin-423 is a short antimicrobial peptide and displays bactericidal activities against several food-borne pathogens and spoilage Gram positive bacteria. The goal of this study was to investigate the potential of using immobilized plantaricin for capturing microorganisms on glass arrays. The peptide used for immobilization consists of N-terminal domain of Plantaricin-423 with an additional cysteine (Pln-17C) to form disulfide bonds with thiol groups present on silanized slides. Our results showed that Pln-17C is able to capture all six strains that were tested with varying affinities. The cell capture occurred within five minutes of incubation and the binding level was highest for Listeria innocua followed by other Gram positive strains tested. Pln-17C was also able to capture Escherichia coli with lower affinity, but the binding was significantly lower for Mycobacterium smegmatis compared to other strains. In addition, we have observed that immobilized Pln-17C maintained its anti-listerial activity; however, it did not kill E. coli as expected. Our results demonstrate the feasibility of utilizing antimicrobial peptides in biosensors for pathogen detection and for creating antimicrobial surfaces. Moreover, in combination with other peptides, different target species from food-borne pathogens to biodefense agents can be captured on more stable, economic, and robust platforms. (C) 2015 Elsevier B.V. All rights reserved.