Güncel Gönderiler: Fen Fakültesi
Toplam kayıt 2379, listelenen: 1281-1300
-
FTIR spectroscopic and theoretical study of the photochemistry of matrix-isolated coumarin
(Wiley, 2007)The infrared spectrum of monomeric unsubstituted coumarin (C9H6O2; 2H-1-benzopyran-2-one), isolated in solid argon at 10 K is presented and assigned. The UV-induced (lambda > 200 nm) unimolecular photochemistry of the ... -
Novel fused D-A dyad and A-D-A triad incorporating tetrathiafulvalene and p-benzoquinone
(American Chemical Society, 2004)Novel fused donor-acceptor dyad (TTF-Q or D-A) and acceptor-donor-acceptor triad (Q-TTF-Q or A-D-A) incorporating the donor tetrathiafulvalene (TTF) and the acceptor p-benzoquinone (Q) have been synthesized. The solution ... -
NMR spectra, GIA and charge density calculations of five-membered aromatic heterocycles
(Wiley-Blackwell, 2007)The B3LYP/6-31+G(d) molecular geometry optimized structures of 17 five-membered heterocycles were employed together with the gauge including atomic orbitals (GIAO) density functional theory (DFT) method at the B3LYP/6-31+G(d,p), ... -
An ab initio study on protonation of some substituted thiazole derivatives
(Elsevier Science BV, 2005)The preferred tautomeric forms of some 2-oxothiazole derivatives were predicted using acidity constants calculated by experimental and ab initio methods. Thiazole derivatives were subject to geometry optimization at two ... -
A theoretical study of substituent effects on tautomerism of 2-hydroxybenzimidazoles
(Springer-Verlag, 2003)The geometries, relative stabilities of some 4(7) and 5(6) substituted 2-hydroxybenzimidazole derivatives were calculated with full geometry optimization using AM1 and PM3 in aqueous phase. With the exception of molecules ... -
A quantum chemical study on structures of (+)-(R)-2,2-bis(diphenylphosphinoyl)-1,1 '-binaphthyl and its hydroquinone complex
(Elsevier Science BV, 2005)The (+)-(R)-2,2-bis(diphenylphosphinoyl)-1,1'-binaphthyl ((+)-(R)-BINAPO) and its cocrystal with hydroquinone (HQ) (1:1) were studied theoretically with AM1, PM3, MNDO and MINDO/3 semi-empirical methods to elucidate their ... -
Spectroscopic determination of acid dissociation constants of some pyridyl Shiff bases
(American Chemical Society, 2006)The acid dissociation constants (pK(a)) of eight biologically active pyridyl Shiff bases were determined using a UV-vis spectroscopic technique at 25 +/- 0.1 degrees C. The first acidity constants (pK(a1)) of the ... -
Electrodeposition of polyaniline, poly(2-iodoaniline), and poly(aniline-co-2-iodoaniline) on steel surfaces and corrosion protection of steel
(Elsevier Science BV, 2005)Polyaniline (PANi), poly(2-iodoaniline) (PIANi), and poly(aniline-co-2-iodoaniline) (co-PIANi) were synthesized using cyclic voltammetry in acetonitrile solution containing tetrabuthylammonium perchlorate (TBAP) and ... -
Inhibition of the corrosion of low carbon steel in acidic solution by selected polyelectrolytes and polymers
(Emerald Group Publishing Limited, 2003)The inhibiting effects of 2,6-ionen and 2,10-ionen type polyvinylbenzyltrimethylammonium chloride, and latex, on low carbon steel in hydrochloric acid solution was investigated by potentiodynamic polarisation measurements ... -
A quantum chemical study on structure of 1,2-bis(diphenylphosphinoyl)ethane and phenol cocrystal
(Elsevier Science BV, 2004)The cocrystal of 1,2-bis(diphenylphosphinoyl)ethane (DPPEO) with phenol (1: 1) were studied theoretically with AM1, PM3, MNDO and MINDO/3 semi-empirical methods to elucidate its structure. The bond lengths and angles from ... -
Investigation of acid-base behaviour of some 2-pyridylbenzimidazoles using semi-empirical methods
(Elsevier Science BV, 2002)Acid-base behaviour of some 2-(n'-pyridyl) benzimidazoles (n' = 2,3,4) have been studied in order to search the protonation site and to predict pK(a) values of these molecules both in gas and aqueous phases using semi-empirical ... -
Quantum chemical and experimental studies on the mechanism of alkylation of beta-dicarbonyl compounds. The synthesis of five and six membered heterocyclic spiro derivatives
(MDPI, 2004)The alkylation of beta-dicarbonyl compounds in a K2CO3/DMSO system was found to afford O- and C-alkylated derivatives, depending on the type of the P-dicarbonyl compound involved. The alkyl derivatives obtained were used ... -
Investigation of the structure and the properties of the potentially tautomeric 1,2-dihydro-5,7-dimethyl-6H-pyrrolo[3,4-d]pyridazine-1-ones in the gas and aqueous phases using semiempirical methods
(Elsevier Science BV, 1998)Potentially tautomeric 1,2-dihydro-5,7-dimethyl-6H-pyrrolo[3,4-d]pyridazine-1-ones and their fixed tautomeric forms have been studied, in order to predict their tautomeric equilibrium constants and pK(a) values, using ... -
Electrochemical synthesis and anti-corrosive properties of polyaniline, poly(2-anisidine), and poly(aniline-co-2-anisidine) films on stainless steel
(Elsevier Science Sa, 2005)Stable and adherent polymer films of polyaniline and of poly(2-anisidine) were grown on 304-stainless steel by cyclic voltammetry in tetrabutylammonium perchlorate/acetonitrile solution containing perchloric acid. Conducting ... -
(mu-Perfluorosebacato-kappa O-2 : O ')bis[aquabis(1,10-phenanthroline-kappa N-2,N ')zinc(II)] perfluorosebacate bis[triaqua(perfluorosebacato-kappa O)(1,10-phenanthroline-kappa N-2,N ')zinc(II)] 3.32-hydrate
(Blackwell Publishing, 2006)The asymmetric unit of the title compound, [Zn-2{O2C(CF2)(8)CO2}(C12H8N2)(4)(H2O)(2)](C10F16O4)center dot[Zn{O2C(CF2)(8)CO2}(C12H8N2)(H2O)(3)]center dot 3.32H(2)O, contains a neutral mononuclear [ZnL(phen)(H2O)3] complex ... -
Determination of the equilibrium, kinetic and thermodynamic parameters of adsorption of copper(II) ions onto seeds of Capsicum annuum
(Elsevier Science BV, 2005)Adsorption of copper ions onto Capsicum annuum (red pepper) seeds was investigated with the variation in the parameters of pH, contact time, adsorbent and copper(II) concentrations and temperature. The nature of the possible ... -
A quantum chemical study on structure of 1,2-bis(diphenylphosphinoyl)ethane and hydroquinone cocrystal
(Elsevier Science BV, 2005)The cocrystal of 1,2-Bis(diphenylphosphinoyl)ethane (DPPEO) with hydroquinone (HQ) (1: 1) were studied theoretically with MINDO/3, MNDO, PM3 and AM I semi-empirical methods to elucidate its structure. The bond lengths and ... -
A theoretical search on metal-ligand interaction mechanism in corrosion of some imidazolidine derivatives
(Elsevier Science BV, 2003)The interaction mechanism of some imidazolidine derivatives with metallic Zn in gas phase, using semiempirical methods, was studied at elevated temperature and the obtained data were used to search a possible correlation ... -
Poly(ethylene dimethacrylate-glycidyl methacrylate) monolith as a stationary phase in dye-affinity chromatography
(American Chemical Society, 2004)Porous monolith was obtained by the bulk polymerization of ethylene dimethacrylate (EDMA) and glycidyl methacrylate (GMA) conducted in a glass tube. Poly(EDMA-GMA) monolith had a specific surface area of 98.7 m(2)/g. ... -
Preparation of sulfonated overoxidized polypyrrole film applicable as an SPME tool for cationic analytes
(Elsevier Science Sa, 2004)The use of a solid-phase microextraction (SPME) method with a new design of functionalized stable overoxidized sulfonated polypyrrole (OSPPy) film electrode to extract metal ions (Ni(II) and Cd(II)) without derivatization ...