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Full-Text Articles in Physical Sciences and Mathematics

Synthesis And Biological Activity Of Allosteric Modulators Of Gaba_B Receptors. Part 4. Synthesis Of Potentially Fluorescent Acridines And Conformationally Restricted N-(Arylpropyl)-1-Arylethylamines, Jabbar Khalafy, Rolf H. Prager, Ni Made Puspawati Jan 2008

Synthesis And Biological Activity Of Allosteric Modulators Of Gaba_B Receptors. Part 4. Synthesis Of Potentially Fluorescent Acridines And Conformationally Restricted N-(Arylpropyl)-1-Arylethylamines, Jabbar Khalafy, Rolf H. Prager, Ni Made Puspawati

Turkish Journal of Chemistry

A series of 8 new derivatives of fendiline was prepared for evaluation as allosteric modulators of GABA_B receptors: 4 based on acridine and 4 with restricted distance between the 2 aryl moieties.


Preparation And Morphological Characterization Of A Catalytic Soot Oxidation Sic Foam Filter, Başar Çağlar, Deni̇z Üner Jan 2007

Preparation And Morphological Characterization Of A Catalytic Soot Oxidation Sic Foam Filter, Başar Çağlar, Deni̇z Üner

Turkish Journal of Chemistry

The coating characteristics of Pb-Co mixed metal oxide soot oxidation catalysts over a SiC foam filter were studied. The coating was done via incipient wetness impregnation of a slurry with Pb/Co weight ratio = 2. The coating was accomplished by 3 consecutive impregnation-drying-calcination cycles. After each cycle surface structure and composition were monitored by scanning electron microscope (SEM). SEM analysis revealed that the surface composition of Pb was high on the high porosity region and surface composition of Co was high on the low porosity region inside the filter. These overlayers were tested for their soot oxidation ability by depositing …


Gold(Iii) Complex Of Caffeine: Synthesis, Isolation And Spectroscopic Characterization, Bojidarka Ivanova Jan 2007

Gold(Iii) Complex Of Caffeine: Synthesis, Isolation And Spectroscopic Characterization, Bojidarka Ivanova

Turkish Journal of Chemistry

Au(III)-caffeine complex was synthesized and characterized by means of solid-state linear-dichroic infrared spectral analysis (IRLD), ^1H-NMR, MS, DSC and TGA methods. The caffeine (I) is monodentate and coordinated with metal ion through its N9 atom at molar ratio metal to ligand 1:1. The other 3 positions in the Au(III) coordination sphere are occupied by Cl^-, thus forming [Au^{3+}(C_8H_{10}N_4O_2)Cl_3] complex. IR-characteristic band assignment in the 4000-400 cm^{-1} IR region of pure ligand and corresponding Au(III)complex was performed.


Electrochemical Characteristics Of A 7-Ferrocenyl(Carbonyloxy)-1- Heptanethiol-Modified Gold Electrode, Mohammed Muzibur Rahman, Il Cheol Jeon Jan 2007

Electrochemical Characteristics Of A 7-Ferrocenyl(Carbonyloxy)-1- Heptanethiol-Modified Gold Electrode, Mohammed Muzibur Rahman, Il Cheol Jeon

Turkish Journal of Chemistry

The electrochemical properties of 7-ferrocenyl(carbonyloxy)-1-heptanethiol [FcCO_2(CH_2)_7SH] were characterized by an electrochemical quartz crystal microbalance (EQCM). A gold surface was modified with FcCO_2(CH_2)_7SH by the self-assembly method. EQCM was used to investigate mass change during the redox reactions of FcCO_2(CH_2)_7SH monolayers on a modified gold electrode in solution containing K_3Fe(CN)_6 redox species. The FcCO_2(CH_2)_7SH monolayer on gold acts as a mediator for the electron transfer between a gold electrode and electroactive species Fe(CN)_6^{3-/4-} in solution. In both cases, electrochemical current responses were complicated because the observed currents were due to the redox of both the ferrocenyl group immobilized on gold and …


Preparation And Characterization Of An Atenolol Selective Electrode Based On A Pvc Matrix Membrane, Nabil S. Nassory, Shabaz A. Maki, Mutaz A. Ali Jan 2007

Preparation And Characterization Of An Atenolol Selective Electrode Based On A Pvc Matrix Membrane, Nabil S. Nassory, Shabaz A. Maki, Mutaz A. Ali

Turkish Journal of Chemistry

Atenolol selective electrodes were prepared based on a complex atenolol-phosphotungstate as an active material using the plasticizers di-butyl phosphate (DBP), tri-butyl phosphate (TBP), o-nitro phenyl octyl ether (NPOE) and di-octyl phthalate (DOPH) in a PVC matrix membrane. The properties of the prepared electrodes were studied, namely slope, concentration range, detection limit, lifetime, pH effect and selectivity. The experimental results showed that the best electrode was based on DOPH as plasticizer, displaying a linear range from 1.00 x 10^{-4} M to 5.00 x 10^{-2} M with a Nernstian slope of 55.91 mV/decade and correlation coefficient of 0.9995. The detection limit was …


Studies On The Preparation Of \Alpha,\Omega -Telechelic Polymers By The Combination Of Reverse Atom Transfer Radical Polymerization And Atom Transfer Radical Coupling Processes, Bi̇nnur Aydoğan, Yusuf Yağci Jan 2007

Studies On The Preparation Of \Alpha,\Omega -Telechelic Polymers By The Combination Of Reverse Atom Transfer Radical Polymerization And Atom Transfer Radical Coupling Processes, Bi̇nnur Aydoğan, Yusuf Yağci

Turkish Journal of Chemistry

Monofunctional polystyrenes with cyano, carboxylic acid, and hydroxyl terminal groups were synthesized by reverse atom transfer radical polymerization (RATRP) using corresponding azo initiators in conjunction with copper and iron complexes. These functional polymers were further used in the atom transfer radical coupling (ATRC) reaction in the presence of Cu(I) and Cu(0) in order to obtain telechelic polystyrenes. In the iron-mediated system, while RATRP experiments gave satisfactory results, the corresponding ATRC process yielded polymers with low functionality. The copper-mediated system, however, gave contrary results. In the RATRP step, initiation efficiency was rather low and polymers with relatively higher polydispersity were obtained. …


Plasma-Initiated Polymerization Of (2-Methacryloyloxyethyl) Thrimethyl Ammonium Chloride, Yangang He, Gang Li, Jing Miao, Xueqing Yu, Fang Yang, Yingjun Cui, Fengxia Ren, Yang Chao Jan 2007

Plasma-Initiated Polymerization Of (2-Methacryloyloxyethyl) Thrimethyl Ammonium Chloride, Yangang He, Gang Li, Jing Miao, Xueqing Yu, Fang Yang, Yingjun Cui, Fengxia Ren, Yang Chao

Turkish Journal of Chemistry

Plasma-initiated polymerization of (2-methacryloyloxyethyl) thrimethyl ammonium chloride (MTAC)) was studied. The effects of discharge time and discharge power on temperature in a tubular-type reactor chamber were accurately tested by on-line thermocouple, and the equation relating discharge time, discharge power and temperature in the tubular-type reactor chamber was derived. The results indicated that temperature played a very important role in controlling the solubility of Poly(MTAC) in water. For T \ge 130°, Poly(MTAC) was cross-linked, and the highest rate of absorbing water of Poly(MTAC) was 15 g · g^{-1}. For T < 130°, Poly(MTAC) was linear, and the highest intrinsic viscosity of Poly(MTAC) was 420.2 cm^3 · g^{-1}. The polymerization condition of linear Poly(MTAC) was optimized as follows: discharge time 60 s and discharge power 60 W.


Electron Affinities, Solvation Energies And Redox Potentials Of Some Chalcones: Substituents` Effect And Correlation With Semi-Empirical Mo Energies, Abdur Rahman, Rumana Qureshi, Mehvish Kiran, Farzana Latif Ansari Jan 2007

Electron Affinities, Solvation Energies And Redox Potentials Of Some Chalcones: Substituents` Effect And Correlation With Semi-Empirical Mo Energies, Abdur Rahman, Rumana Qureshi, Mehvish Kiran, Farzana Latif Ansari

Turkish Journal of Chemistry

Experimental and theoretical investigations were carried out on 2 sets of chalcones. Set 1 has an OH group on ring A and Set 2 does not, and both have different substituents on ring B at different positions. The experimental investigations comprised cyclic voltammetric (CV) studies to determine the reactivity in terms of redox potentials in DMF at room temperature (23 \pm 1 °C). Electrochemical parameters from cyclic voltammograms were used to evaluate the reversibility of electron transfer, standard reduction potentials, solvation energies, electron affinities, diffusion coefficients, critical scan rates and heterogeneous electron transfer rate constants. Heterogeneous electron transfer rate constants …


Synthesis And Spectral Characterisation Of Chloro Organotin(Iv) Di[3(2`-Hydroxyphenyl)-5-(4-Substituted Phenyl) Pyrazolinates], Umesh Nath Tripathi, Mohammad Safi Ahmad, Goriparthi Venubabu Jan 2007

Synthesis And Spectral Characterisation Of Chloro Organotin(Iv) Di[3(2`-Hydroxyphenyl)-5-(4-Substituted Phenyl) Pyrazolinates], Umesh Nath Tripathi, Mohammad Safi Ahmad, Goriparthi Venubabu

Turkish Journal of Chemistry

Chloro organotin(IV) dipyrazolinates of the type RSnCl(C_{15}H_{12}N_2OX)_2 [where C_{15}H_{12}N_2OX = 3(2'-Hydroxyphenyl)-5(4-X-phenyl)pyrazoline {where X = H (a); CH_3 (b); OCH_3 (c); Cl (d) and R = Me, Pr^n and Ph] were synthesised by the reaction of RSnCl_3 with sodium salt of pyrazolines in 1:2 molar ratio, in anhydrous benzene. These newly synthesised derivatives were characterised by elemental analysis (C, H, N, Cl and Sn), molecular weight measurement and spectral [IR and multinuclear NMR (^1H, ^{13}C and ^{119}Sn)] studies. The bidentate behaviour of the pyrazoline ligands was confirmed by IR, ^1H and ^{13}C NMR spectral data. An octahedral structure around the tin(IV) …


Synthesis And Characterization Of Oligo-2-[(2-Hydroxymethylphenylimino) Methyl] Phenol And Oligo-2-[(2-Hydroxymethylphenylimino) Methyl]-5-Bromo-Phenol, İsmet Kaya, Ayşe Erçağ, Süleyman Çulhaoğlu Jan 2007

Synthesis And Characterization Of Oligo-2-[(2-Hydroxymethylphenylimino) Methyl] Phenol And Oligo-2-[(2-Hydroxymethylphenylimino) Methyl]-5-Bromo-Phenol, İsmet Kaya, Ayşe Erçağ, Süleyman Çulhaoğlu

Turkish Journal of Chemistry

Oligo-2-[(2-hydroxymethylphenylimino) methyl] phenol O-(2-HMPIMP) and oligo-2-[(2-hydroxymet\-hylphenyl imino) methyl]-5-bromo-phenol O-(2-HMPIMBP) were synthesized by the oxidative polycondensation reaction using air as an oxidant in an aqueous alkaline medium at 70 °C. They were characterized by ^1H-NMR, FT-IR, UV-vis, TG, size exclusion chromatography (SEC) and elemental analysis. According to the SEC analyses, the number-average molecular weight (M_n), weight-average molecular weight (M_w) and polydispersity index (PDI) values of O-2-HMPIMBP and O-2-HMPIMP are 1100, 1600 g mol^{-1} and 1.45; and 6000, 6250 g mol^{-1} and 1.04, respectively. According to TG analyses, the weight losses of O-2-HMPIMP and O-2-HMPIMBP are 98.31% and 96.91%, respectively, at 900 …


New Aromatic Polyamide With Azo And Phosphine Oxide Groups In The Main Chain, Khalil Faghihi, Mohsen Hagibeygi Jan 2007

New Aromatic Polyamide With Azo And Phosphine Oxide Groups In The Main Chain, Khalil Faghihi, Mohsen Hagibeygi

Turkish Journal of Chemistry

A new flame-retardant polyamide containing phosphine oxide and azobenzene moieties in the main chain was synthesized by the solution polycondensation reaction of 4,4`-azodibenzoic acid with bis(3-aminophenyl) phenyl phosphine oxide using thionyl chloride, N-methyl-2-pyrrolidone and pyridine. This new polymer was obtained in high yield (96%) and showed high inherent viscosity (0.55 dL/g) and was characterized by elemental analysis, FT-IR spectroscopy, thermal gravimetric analysis (TGA and DTG) and solubility test. Furthermore, another polyamide was prepared by solution polycondensation reaction of 4,4`-azodibenzoic acid with 1,4-phenylene diamine and its flame-retardant behavior was compared by the use of the LOI with the previous one.


Efficient Method For Tetrahydropyranylation Of Phenols And Alcohols Using 2,4,6-Trichloro[1,3,5]Triazine, Batool Akhlaghinia, Elham Roohi Jan 2007

Efficient Method For Tetrahydropyranylation Of Phenols And Alcohols Using 2,4,6-Trichloro[1,3,5]Triazine, Batool Akhlaghinia, Elham Roohi

Turkish Journal of Chemistry

Alcohols and phenols were tetrahydropyranylated in the presence of 2,4,6-trichloro[1,3,5]triazine in good to excellent yields in acetonitrile.


A Convenient Method For The Preparation Of 2-Aminobenzophenone Derivatives Under Ultrasonic Irradiation, Javad Safaei-Ghomi, Manouchehr Fadaeian, Alireza Hatami Jan 2007

A Convenient Method For The Preparation Of 2-Aminobenzophenone Derivatives Under Ultrasonic Irradiation, Javad Safaei-Ghomi, Manouchehr Fadaeian, Alireza Hatami

Turkish Journal of Chemistry

A quick and convenient method for the preparation of 2-aminobenzophenone derivatives is described. This approach consists of the nucleophilic substitution reaction of nitrobenzenes by phenylacetonitrile under conventional and ultrasonic conditions followed by reduction of the produced 2,1-benzisoxazole to 2-aminobenzophenone. This 2-step reaction was studied by changing the reaction parameters (reaction temperature, ultrasound power, and reaction time). The results clearly demonstrated that using ultrasound irradiation results in a high yield within a short reaction time.


Examination Of Gold As A Metal Promoter Of Sulphated Zirconia In N-Heptane Isomerisation At Low Temperature, Ümi̇t Bi̇lge Demi̇rci̇, Francois Garin Jan 2007

Examination Of Gold As A Metal Promoter Of Sulphated Zirconia In N-Heptane Isomerisation At Low Temperature, Ümi̇t Bi̇lge Demi̇rci̇, Francois Garin

Turkish Journal of Chemistry

Isomerisation of nC_7 over a sulphated zirconia (SZ)-based bifunctional catalyst was studied at 150 °C. Au, Ir, Pd and Pt were used as promoters of SZ. The first objective was the production of C_7 isomers with high octane numbers. PtSZ is the most suitable catalyst despite low conversions and a high proportion of methylhexanes instead of dimethylpentanes. The second objective was to assess Au as a promoter of SZ. Au shows slight hydrogenation abilities, displaying behaviour similar to that of Pd, but is inactive towards alkane activation. These promising but inadequate results suggested that Au could be used as the …


Synthesis And Characterization Of Polyimides Prepared From Optically Active (R,R) And (S,S)-1,3-Bis(P-N,N´-Dimethylaminobenzyl)-Perhydrobenzimidazol-2-Thion, Murat Yi̇ği̇t, Turgay Seçki̇n, Süleyman Köytepe, Engi̇n Çeti̇nkaya Jan 2007

Synthesis And Characterization Of Polyimides Prepared From Optically Active (R,R) And (S,S)-1,3-Bis(P-N,N´-Dimethylaminobenzyl)-Perhydrobenzimidazol-2-Thion, Murat Yi̇ği̇t, Turgay Seçki̇n, Süleyman Köytepe, Engi̇n Çeti̇nkaya

Turkish Journal of Chemistry

This paper presents the synthesis and characterization of polyimides containing a chiral (R,R) or (S,S) 1,3-bis(p-N,N´-dimethylaminobenzyl)-perhydrobenzimidazol-2-thion unit in the backbone. The reactions occur between equimolar amounts of a dianhydride and an aromatic dimethylamine in the presence of the solvent N-methyl-2-pyrollidone (NMP). In this work, the chiral monomer RR and SS -1,3-bis(p-N,N´-dimethylaminobenzyl)-perhydrobenzimidazol- 2-thion were used as diamines. The polyimides obtained were characterized by thermogravimetry (TGA), differential thermal analysis (DTA), differential scanning calorimeter (DSC), infrared spectroscopy (FT-IR), and gel permeation chromatography (GPC). It was found that the composition of the polymer had a significant effect upon the thermal behavior of the material.


Synthesis Of 2-Acylamino, 2-Aroylamino And Ethoxycarbonyl Imino-1,3,4-Thiadiazoles As Antitumor Agents, Kemal Sancak, Yasemi̇n Ünver, Mustafa Er Jan 2007

Synthesis Of 2-Acylamino, 2-Aroylamino And Ethoxycarbonyl Imino-1,3,4-Thiadiazoles As Antitumor Agents, Kemal Sancak, Yasemi̇n Ünver, Mustafa Er

Turkish Journal of Chemistry

2-Amino-1,3,4-thiadiazoles compounds (2a-e) were obtained from the reaction of thiosemi carbazide with 2-cyanomethoxyphenoxyacetonitriles (1). Mono acylamino, mono aroylamino and diethoxycarbonyl imino-1,3,4-thiadiazole compounds (3a-e, 4a-e, 5a-c) were synthesized via the reaction of 2-amino-1,3,4-thiadiazole compounds (2a-e) with acetyl chloride or acetic anhydride, benzoyl chloride or benzoic anhydride and ethyl chloroformate, respectively. The in vitro antitumor activities of some selected compounds were screened and compounds 2a, 2b, 2c, 3a, 3b, 3c, 5a, 5b and 5c were found to be active.


Synthesis Of Nitrogen-Containing Heterocycles From The Reaction Of Amidrazones With \Alpha-Haloesters, Hany M. Dalloul, Peter H. Boyle Jan 2007

Synthesis Of Nitrogen-Containing Heterocycles From The Reaction Of Amidrazones With \Alpha-Haloesters, Hany M. Dalloul, Peter H. Boyle

Turkish Journal of Chemistry

The reaction of amidrazones 1 with \alpha-haloesters 2 formed 1,3,5-substituted 4,5-dihydro-1,2,4-triazin-6-ones (4a-z) rather than 1,2,4-triazin-5-one derivatives (5a-z). The microanalysis and spectral data of the synthesized compounds are in full agreement with their molecular structure.


Iridoid Glucosides From Lamium Garganicum Subsp. Laevigatum, Tayfun Ersöz, Duygu Kaya, Funda Nuray Yalçin, Cavi̇t Kazaz, Erhan Palaska, Charlott H. Gotfredsen, Soren R. Jensen, İhsan Çaliş Jan 2007

Iridoid Glucosides From Lamium Garganicum Subsp. Laevigatum, Tayfun Ersöz, Duygu Kaya, Funda Nuray Yalçin, Cavi̇t Kazaz, Erhan Palaska, Charlott H. Gotfredsen, Soren R. Jensen, İhsan Çaliş

Turkish Journal of Chemistry

Phytochemical investigations on the above-ground parts of Lamium garganicum subsp. laevigatum resulted in the isolation of 7 iridoid glucosides: shanzhiside methyl ester (1), barlerin (8-O-acetylshanzhiside methyl ester) (2), 6-O-syringyl-8-O-acetylshanzhiside methyl ester (3), 6\beta-hydroxyipolamiide (4), lamalbide (5), dehydropenstemoside (6), and sesamoside (7). The structure of the iridoids was elucidated by spectroscopic (UV, IR, 1D- and 2D-NMR, and ESI-MS) evidence.


Investigation Of Some 1,3-Diols For The Requirements Of Solvent Extraction Of Boron: 2,2,6-Trimethyl-1,3 Heptanediol As A Potential Boron Extractant, Bi̇lsen Tural, Servet Tural, Hali̇l Hoşgören Jan 2007

Investigation Of Some 1,3-Diols For The Requirements Of Solvent Extraction Of Boron: 2,2,6-Trimethyl-1,3 Heptanediol As A Potential Boron Extractant, Bi̇lsen Tural, Servet Tural, Hali̇l Hoşgören

Turkish Journal of Chemistry

Eighteen 1,3-diols were synthesized and their structure and distribution ratio for the solvent extraction of boron were studied. Diols with a high distribution ratio (D_{B(OH)_3 > 10) were investigated for the requirements of solvent extraction of boron. Their extraction capacity, and solubility in aqueous phase and in organic diluents were investigated by comparison to 2-ethyl-1,3-hexanediol (EHD), which is widely used as a boron extractant. Among a series of 1,3 diols, 1-benzyl-2,2-dimethyl-1,3-propanediol (4a) and 2,2,6-trimethyl-1,3-heptanediol (3a) were found to have very low solubility in the aqueous phase compared to the others. IPD (3a) was found to have a high solubility in aliphatic …


Investigation Of The Voltammetric Characteristics Of Poly(1,4-Diaminobenzene) Film As A Dopamine-Selective Polymer Electrode, Gamze Erdoğdu, A. Ersi̇n Karagözler Jan 2007

Investigation Of The Voltammetric Characteristics Of Poly(1,4-Diaminobenzene) Film As A Dopamine-Selective Polymer Electrode, Gamze Erdoğdu, A. Ersi̇n Karagözler

Turkish Journal of Chemistry

Electrochemical polymerization of 1,4-diaminobenzene in the KCl aqueous electrolyte at a potential of 0.600 V versus Ag/AgCl produces adherent poly(1,4-diaminobenzene) film on a gold electrode. The electrochemical behavior of dopamine and ascorbic acid at the polymer electrode prepared in this manner was examined by cyclic and differential pulse voltammetry. Voltammetry studies showed that polymeric film with a thickness corresponding to a 7-mC charge exhibited selective permeation for dopamine while retaining ascorbic acid. All the polymerization parameters affecting the permselective characteristics were systematically investigated and the optimum values were determined. The results showed that a polymeric membrane, owing to its permselective …


Synthesis And Physico-Chemical And Spectroscopic Investigations Of Sodium Dihydrobis(1,2,3-Benzotriazolyl)Borate Ligand And Its Transition Metal Complexes, . Lutfullah, Ahmad Umar, Mohammed Muzibur Rahman, Mohammad Mansoob Khan, Yoon Bong Hahn Jan 2007

Synthesis And Physico-Chemical And Spectroscopic Investigations Of Sodium Dihydrobis(1,2,3-Benzotriazolyl)Borate Ligand And Its Transition Metal Complexes, . Lutfullah, Ahmad Umar, Mohammed Muzibur Rahman, Mohammad Mansoob Khan, Yoon Bong Hahn

Turkish Journal of Chemistry

The title ligand, sodium dihydrobis(1,2,3-benzotriazolyl)borate, Na[H_2B(BTz)_2], was synthesized by refluxing 1 mole of sodium borohydride with 2 moles of 1,2,3- benzotriazole in toluene. The ligand shows ample reactivity towards Cr(III), Mn(II), Fe(III), Fe(II), Co(II), Ni(II), Cu(II), Zn(II), Cd(II) and Hg(II) metal ions and forms stable complexes. The ligand and its metal complexes were characterized by physico-chemical and spectroscopic techniques. All the complexes of divalent metal ions are tetrahedral except for Cu(II), which has been proposed to have a square-planar geometry. The complexes of Cr(III) and Fe(III) appear to have an octahedral geometry. The magnitude of molar conductance of 10^{-3} M …


On-Line Preconcentration And Speciation Of Chromium By An 8-Hydroxyquinoline Microcolumn Immobilized On Surfactant-Coated Alumina And Flow Injection Atomic Absorption Spectrometry, Seyyed Hamid Ahmadi, Ali Mohammad Haji Shabani, Shayessteh Dadfarnia, Masoumeh Taei Jan 2007

On-Line Preconcentration And Speciation Of Chromium By An 8-Hydroxyquinoline Microcolumn Immobilized On Surfactant-Coated Alumina And Flow Injection Atomic Absorption Spectrometry, Seyyed Hamid Ahmadi, Ali Mohammad Haji Shabani, Shayessteh Dadfarnia, Masoumeh Taei

Turkish Journal of Chemistry

An on-line technique for the determination of chromium species with atomic absorption spectrometry is described. The method is based on separation and preconcentration of Cr(III) on a microcolumn of immobilized 8-hydroxyquinoline on surfactant-coated alumina. The adsorbed analyte is then eluted with 400 \mu L of 20% ethanolic solution of 1.5 mol L^{-1} hydrochloric acid and is transported to a flame atomic absorption spectrometer for quantification. The effects of pH, sample and eluent flow rate, sorption capacity, and the presence of various cations and anions on the sorption of Cr(III) were investigated. The sorption was quantitative in the pH 6-8 range, …


Hydrothermal Synthesis, Characterization And Photocatalytic Activity Of Nanosized Tio_2 Based Catalysts For Rhodamine B Degradation, Funda Sayilkan, Meltem Asi̇ltürk, Şadi̇ye Şener, Sema Erdemoğlu, Murat Erdemoğlu, Hi̇kmet Sayilkan Jan 2007

Hydrothermal Synthesis, Characterization And Photocatalytic Activity Of Nanosized Tio_2 Based Catalysts For Rhodamine B Degradation, Funda Sayilkan, Meltem Asi̇ltürk, Şadi̇ye Şener, Sema Erdemoğlu, Murat Erdemoğlu, Hi̇kmet Sayilkan

Turkish Journal of Chemistry

Nanosize crystalline TiO_2 and SiO_2/TiO_2 mixed oxide particles as a photocatalyst for rhodamine B dye (RB) degradation in aqueous media were synthesized by a hydrothermal process at 200 °C. They were characterized using XRD, SEM, FT-IR, UV/VIS and BET analysis. The effects of silica content on the crystallinity and photocatalytic activity of TiO_2 were investigated. Photocatalytic activity of the nano-TiO_2 was compared with that of SiO_2/TiO_2 mixed oxides at the same conditions for degradation of RB, and mixed oxide catalysts showed more effective catalytic activity than the TiO_2. The results revealed that photodegradation of RB proceeds by pseudo-first-order reaction kinetics …


Template-Free Synthesis Of Zsm-5 Type Zeolite Layers On Porous Alumina Disks, Hali̇l Kalipçilar, Ali̇ Çulfaz Jan 2007

Template-Free Synthesis Of Zsm-5 Type Zeolite Layers On Porous Alumina Disks, Hali̇l Kalipçilar, Ali̇ Çulfaz

Turkish Journal of Chemistry

ZSM-5 crystals were synthesized from template-free batches on macroporous \alpha-alumina disks. The SiO_2/Al_2O_3 ratio of the synthesis gel influenced the crystal morphology, surface coverage and intergrowth among the crystals. Prismatic ZSM-5 crystals covered the disk surface when the SiO_2/Al_2O_3 ratio of the batch was higher than 100, whereas spherical polycrystalline particles of ZSM-5 were obtained from batches with a SiO_2/Al_2O_3 ratio of 80. Mordenite type zeolite was formed on the disk surface due to the incorporation of alumina dissolved from the disk when the time of crystallization was extended. The effects of silica source and seeding of the support surface …


An Electrochemical Dna Biosensor For The Detection Of Dna Damage Caused By Radioactive Iodine And Technetium, Pinar Kara, Kağan Dağdevi̇ren, Mehmet Özsöz Jan 2007

An Electrochemical Dna Biosensor For The Detection Of Dna Damage Caused By Radioactive Iodine And Technetium, Pinar Kara, Kağan Dağdevi̇ren, Mehmet Özsöz

Turkish Journal of Chemistry

A DNA damage process by radioactive iodine (I-131) and technetium (Tc-99m) is described. The procedure relies on a label-free electrochemical DNA biosensor. Fish sperm double stranded DNA was immobilized onto a carbon paste electrode (CPE) by electro deposition and the changes to the guanine oxidation signal were observed upon exposure to radioactive I-131 and Tc-99m by differential pulse voltammetry (DPV). The changes to the signal of guanine after exposure to therapeutic doses of Tc-99m and I-131 showed conformational changes in DNA molecules.


Preparation And Properties Of Triethoxyvinylsilane-Modified Styrene - Butyl Acrylate Emulsion Copolymers, Hamit Javaherian Naghash, Akram Karimzadeh, Ahmad Reza Momeni, Ahmad Reza Massah, Hamid Alian Jan 2007

Preparation And Properties Of Triethoxyvinylsilane-Modified Styrene - Butyl Acrylate Emulsion Copolymers, Hamit Javaherian Naghash, Akram Karimzadeh, Ahmad Reza Momeni, Ahmad Reza Massah, Hamid Alian

Turkish Journal of Chemistry

The copolymers of triethoxyvinylsilane (TEVS) with styrene (St), butyl acrylate (BA), and methacrylic acid (MAA) were prepared by emulsion polymerization. The copolymerization was carried out by using auxiliary agents at 90 °C in the presence of potassium peroxodisulfate (KPS) as the initiator. Nonylphenol ethylene oxide -- 40 units (NP-40) and sodium lauryl sulfoacetate (SLSA) were used as nonionic and anionic emulsifiers, respectively. The resulting copolymers were characterized by Fourier transform infrared spectroscopy (FTIR). Thermal properties of the copolymers were studied by thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC). The morphology of copolymers was also investigated by optical microscopy (OM) …


Mono-, Di- And Trinuclear Copper(Ii) Complexes Of A Schiff Base Ligand, 2-{(E)-[(6-{[(1e)-(2-Hydroxyphenyl)Methylene]Amino}Pyridin-2-Yl)Imino]-Methyl}Phenol, Nevi̇n Karaböcek, Serdar Karaböcek, Fatma Kormali Jan 2007

Mono-, Di- And Trinuclear Copper(Ii) Complexes Of A Schiff Base Ligand, 2-{(E)-[(6-{[(1e)-(2-Hydroxyphenyl)Methylene]Amino}Pyridin-2-Yl)Imino]-Methyl}Phenol, Nevi̇n Karaböcek, Serdar Karaböcek, Fatma Kormali

Turkish Journal of Chemistry

A Schiff base ligand, 2-{(E)-[(6-[(1E)-(2-hydroxyphenyl) methylene]amino}-pyridin-2-yl)imino]-methyl} phenol (H_2PySAL), was prepared by condensation of 2,6-diaminopyridine and salicylaldehide in EtOH. The Schiff base ligand was checked by elemental analyses, ^1H-NMR, ^{13}C-NMR, IR, UV/Vis, and mass spectral studies. Three new mono-, di-, and trinuclear copper(II) complexes of the Schiff base ligand, formula [Cu(H_2PySAL)]Cl_2, [Cu_2(PySAL) (Phen)]Cl_2, [Cu_3(PySAL)_2]Cl_2, were prepared and characterized by elemental analyses, magnetic moment, and IR, Uv/Vis, and mass spectral studies. The spectroscopic data of the complexes indicate that the copper(II) ions are coordinated by the oxygen atoms and nitrogen atoms (C=N) of the ligand. In the dinuclear complex, in which the …


Fft-Adsorptive Voltammetric Technique For Pico-Level Determination Of Tetracycline In Capsules At An Au Microelectrode In Flowing Solutions, Parviz Norouzi, Mohammad Reza Ganjali, Parandis Daneshgar Jan 2007

Fft-Adsorptive Voltammetric Technique For Pico-Level Determination Of Tetracycline In Capsules At An Au Microelectrode In Flowing Solutions, Parviz Norouzi, Mohammad Reza Ganjali, Parandis Daneshgar

Turkish Journal of Chemistry

This study illustrates a novel method for fast monitoring of tetracycline in flow-injection systems. The fast Fourier transformation, along with continuous cyclic voltammetry (FFTCV) at a gold microelectrode in a flowing solution system, was used for the determination of tetracycline in its pharmaceutical formulation. The benefit of the developed technique is that it is simple, precise, accurate, time-saving, and economical compared to all of the previously reported methods. The effects of various parameters on the sensitivity of the method were investigated. Three considerable advantages are demonstrated by this method, which other methods do not possess. Firstly, there is no requirement …


Speciation Of Manganese Using A Pneumatic Flow Injection Analysis-Tandem Spectrometer System, Meissam Noroozifar, Mozhgan Khorasani-Motlagh, Reza Akbari Jan 2007

Speciation Of Manganese Using A Pneumatic Flow Injection Analysis-Tandem Spectrometer System, Meissam Noroozifar, Mozhgan Khorasani-Motlagh, Reza Akbari

Turkish Journal of Chemistry

A pneumatic flow injection-tandem spectrometer system, without a delivery pump, was used for the speciation of manganese (Mn). In this system the suction force of the pneumatic nebulizer of a flame atomic absorption spectrometer (FAAS) was used for solution delivery through the manifold. Mn(VII) and total Mn (Mn(VII) and Mn(II)) concentrations were determined using a UV-Vis spectrometer and FAAS, respectively. The Mn(II) concentration was determined by the difference between the two. The calibration curves were linear up to 15.00 mg L^{-1} for Mn(VII) and total Mn, with a detection limit of 0.08 mg L^{-1} and 0.05 mg L^{-1} for Mn(VII) …


Studies On The Anion Recognition Properties Of Synthesized Receptors Iii: A Novel Thiourea-Based Receptor Constructed By Benzo-15-Crown-5 For Sensing Anions In A Strong Polar Solvent, You-Ming Zhang, Hai-Xian Ren, Yan-Qing Zhou, Rong Luo, Wei-Xia Xu, Tai-Bao Wei Jan 2007

Studies On The Anion Recognition Properties Of Synthesized Receptors Iii: A Novel Thiourea-Based Receptor Constructed By Benzo-15-Crown-5 For Sensing Anions In A Strong Polar Solvent, You-Ming Zhang, Hai-Xian Ren, Yan-Qing Zhou, Rong Luo, Wei-Xia Xu, Tai-Bao Wei

Turkish Journal of Chemistry

A new series of receptors were designed and synthesized, and their interactions with anions, such as F^-, Cl^-, Br^-, I^-, CH_3COO^-, HSO_4^-, and NO_3^-, in DMSO solvent were investigated using UV-Vis absorption spectroscopy. The results showed that hydrogen-bonding complexes were formed between the receptors and the tested anions, such as CH_3COO^- and F^-. It was also found that the selectivity of the receptors for anions could be efficiently tuned by changing the place of the substituent group at the N-phenyl moiety. The recognition mechanism and binding mode are discussed. These findings were expected to be of significance for designing and …