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Publication Metadata only Investigation of Adsorption of 5-Fluorouracil and 5-Bromouracil onto Sepiolite and Loughlinite: An IR Spectroscopic Study(Asian Journal Of Chemistry, 11/100 Rajendra Nagar, Sector 3,, Sahibabad 201 005, Ghaziabad, India, 2014-08) Akalın, Elif; AKYÜZ, SEVİM; AKYÜZ, ZEKİ TANIL; 10127; 46357The adsorption of 5-fluorouracil (5FU) and 5-bromouracil (5BrU) by sepiolite and loughlinite (natural Na-sepiolite) has been investigated using FT-IR spectrometry. The spectroscopic results indicate that 5-halogenouracils adsorbed on sepiolite and loughlinite are coordinated to surface hydroxyls and/or to Lewis acidic centers by hydrogen bonding interaction through the oxygen lone pairs. Some intensity and frequency changes in the OH stretching and deformation bands of surface hydroxyls (Si-OH) of the 5-fluorouracil and 5-bromouracil treated sepiolite and loughlinite were observed. Adsorption capacity of the sepiolite is found to be higher than loughlinite for 5-halogenuracils. Moreover adsorption capacity of clays were found to decrease in the order 5-fluorouracil >5-bromouracil.Publication Metadata only FT-IR spectroscopic investigation of adsorption of pyrimidine on sepiolite and montmorillonite from Anatolia(Springer, Van Godewijckstraat 30, 3311 Gz Dordrecht, Netherlands, 2003-06) AKYÜZ, SEVİM; AKYÜZ, ZEKİ TANIL; 10127The adsorption of pyrimidine ( PM) on natural montmorillonite and sepiolite from Turkey was investigated by FT-IR spectroscopy. The intercalation of PM within montmorillonite has been shown by X-ray diffraction to increase the interlayer spacing. The spectroscopic results indicate that PM molecules adsorbed on sepiolite are coordinated to Lewis acidic centers or surface hydroxyls by H-bonding interaction through one of the pyrimidine ring nitrogen lone pairs. Moreover, some of the adsorbed PM molecules may enter the interior channels of the sepiolite structure and replace zeolitic water. The intercalated PM molecules within montmorillonite are coordinated to exchangeable cations directly or indirectly through water bridges.Publication Metadata only FT-IR spectroscopic investigations adsorption of pyrazinamide and 4-aminopyrimidine by clays(SPRINGER, VAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDS, 2004-02) AKYÜZ, SEVİM; AKYÜZ, ZEKİ TANILThe adsorption of pyrazinamide (PZA) and 4-aminopyrimidine (4APM) on natural sepiolite, loughlinite (Na-sepiolite), natural and ion-exchanged montmorillonite (Co- or Cu-montmorillonite) has been investigated using FT-IR spectroscopy. The intercalation of pyrazinamide and 4-aminopyrimidine within natural and ion-exchanged montmorillonites has been shown by X-ray diffraction to increase the interlayer spacing. PZA and 4APM interacted with montmorillonites by direct or indirect coordination ( through water molecules) to the exchangeable cations. The spectroscopic results indicate that PZA or 4APM molecules adsorbed on sepiolite and loughlinite are coordinated to Lewis acidic centers or surface hydroxyls by H-bonding interaction through either one of the pyrimidine ring nitrogen lone pairs ( in the case of 4APM) or carbonyl group ( in the case of PZA).Publication Metadata only FT-IR Spectroscopic Study Of Terra-Cotta Sarcophagi Recently Excavated In Ainos (Enez) Turkey(Elsevier Science Bv, Po Box 211, 1000 Ae Amsterdam, Netherlands, 2010-07-15) Kurap, Gülnur; Başaran, Sait; Çakan, Banu; AKYÜZ, SEVİM; AKYÜZ, ZEKİ TANIL; TR136713; TR10127; TR111424; TR53588In this study, painting materials and body samples of the decorated terra-cotta sarcophagi, and the body samples of six terra-cotta sarcophagi, recently excavated in Ancient Ainos (Enez) Turkey, were investigated, using the FT-IR spectrometry. EDXRF spectrometry was used as a complementary technique. The experimental results allowed us to identify the mineralogical composition of body samples and main pigments of the decorated parts of the terra-cotta sarcophagi. Spectroscopic results revealed that the investigated samples were fired to a temperature less than 750 degrees C. in the oxidising atmosphere. (C) 2010 Elsevier B.V. All rights reserved.Publication Metadata only FT-IR spectra of natural loughlinite (Na-sepiolite) and adsorption of pyrimidine on loughlinite(ELSEVIER SCIENCE BV, PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS, 2004-11-01) AKYÜZ, SEVİM; AKYÜZ, ZEKİ TANILFT-IR spectroscopy has been used to characterise natural loughlinite and the adsorption of pyrimidine. A comparison of the spectra of loughlinite and sepiolite are given. The adsorption of pyrimidine was on the loughlinite Lewis acid cites through the pyrimidine lone pairs. Moreover. some of the adsorbed pyrimidine molecules may coordinate to surface SiOH groups. (C) 2004 Elsevier B.V. All rights reserved.Publication Metadata only Adsorption and interaction of 2-aminopyridine with loughlinite (Na-sepiolite) from Anatolia(ASIAN JOURNAL OF CHEMISTRY, 11/100 RAJENDRA NAGAR, SECTOR 3,, SAHIBABAD 201 005, GHAZIABAD, INDIA, 2008-06) AKYÜZ, SEVİM; AKYÜZ, ZEKİ TANIL; TR10127; TR111424FT-IR spectroscopy has been used to characterize adsorption and interaction of 2-aminopyridine by loughlinite, which belongs to palygorskite-sepiolite group of phyllosilicates class of clay minerals. The spectroscopic results indicate generation of 2-aminopyridinium cations. Cationic and neutral surface species adsorbed on loughlinite are coordinated to Bronsted acidic sites and surface hydroxyls (by H-bonding interaction through pyridine ring nitrogen lone pairs), respectively. It must be noted that the adsorption of 2-aminopyridine affected the hydroxyl group vibrations of loughlinite.Publication Metadata only FTIR spectroscopy of protein isolates of salt-tolerant soybean mutants(Springer, 233 Spring St, New York, Ny 10013 USA, 2018-01) AKYÜZ, SEVİM; AKYÜZ, ZEKİ TANIL; ATAK, ÇİMEN; ÇELİK, ÖZGE; 10127; 113987; 6653The effect of salinity on the conformation of proteins of four salt-tolerant M-2 generation mutants of soybean plants (S04-05/150-2, S04-05/150-8, S04-05/150-106, and S04-05/150-114) was investigated using Fourier transform infrared (FTIR) spectroscopy. Salinity is one of the important abiotic stress factors that limits growth and productivity of plants. The mutants belonging to the M-2 generation were determined as tolerant to 90 mM NaCl. The relative contents of alpha-helix, beta-sheet, turn, and irregular conformations for the soybean protein isolates were determined depending on the analysis of the amide I region. The comparison of the secondary structures of soybean proteins of the mutants with those of the control group indicated that the alpha-helix structure percentage was diminished while beta-turn and disordered structures were increased as a result of the salt stress.Publication Metadata only Adsorption Of Isoniazid Onto Sepiolite-Palygorskite Group Of Clays: An IR Study(Pergamon-Elsevier Science Ltd, The Boulevard, Langford Lane, Kidlington, Oxford Ox5 1Gb, England, 2010-04) Akalın, Elif; AKYÜZ, SEVİM; AKYÜZ, ZEKİ TANIL; TR10127; TR111424; TR46357The adsorption of isoniazid (INH) on sepiolite, loughlinite (natural Na-sepiolite) and palygorskite from Anatolia was investigated by FT-IR spectroscopy. Experimental results indicated that INH molecules, adsorbed on sepiolite-palygorskite group of clays, are coordinated to surface hydroxyls by H-bonding interaction through the pyridine ring nitrogen lone pairs. Moreover, some of the adsorbed INH molecules may enter the interior channels of the sepiolite-palygorskite structure and involve H-bonding interaction with zeolitic water. Some intensity and frequency changes in the OH stretching band of surface hydroxyls (Si-OH) of the INH-treated sepiolite and loughlinite were observed. However, this band is found to be less affected by the adsorption of isoniazid in the case of palygorskite, probably because the surface Si-OH groups in palygorskite appear to be less abundant than in sepiolite or loughlinite. (C) 2010 Elsevier B.V. All rights reserved.Publication Metadata only Adsorption of Isonicotinamide on Loughlinite (Natural Na-Sepiolite): An FT-IR Spectroscopic Study(Asian Journal Of Chemistry, 11/100 Rajendra Nagar, Sector 3, Sahibabad 201 005, Ghaziabad, India, 2014-07) AKYÜZ, ZEKİ TANIL; AKYÜZ, SEVİM; 10127In this study adsorption of isonicotinamide on loughlinite (Na-sepiolite) has been investigated by FT-IR spectroscopy. The adsorption of isonicotinamide showed a considerable alteration on both Si-OH stretching and deformation peaks of loughlinite structure. Spectroscopic results indicate that adsorbed isonicotinamide molecules onto loughlinite are coordinated to surface silanol groups and/or Lewis acidic centers by H-bonding interaction through pyridine ring nitrogen lone pairs. The amino nitrogen is found to be relatively in active to adsorbing sites.Publication Metadata only Adsorption Of 3-And 4-Aminopyridine On Loughlinite-An IR Spectroscopic Study(Elsevier Science Bv, Po Box 211, 1000 Ae Amsterdam, Netherlands, 2010-05-26) AKYÜZ, SEVİM; AKYÜZ, ZEKİ TANIL; TR10127; TR111424In this study adsorption of 3- and 4-aminopyridine on loughlinite (Na-sepiolite) have been investigated by FT-IR spectroscopy. Spectroscopic results indicate that sorbed aminopyridine molecules onto loughlinite are coordinated to Lewis acidic centers, zeolitic/bound water molecules, and surface silanol groups by hydrogen bonding interaction through pyridine ring nitrogen lone pairs. Some of the adsorbed molecules coordinate to Bronsted acidic centers and aminopyridinium cationic surface species are also generated. (C) 2010 Elsevier B.V. All rights reserved.