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Geochemical Constraints On The Provenance, Mineral Sorting And Subaerial Weathering Of Lower Jurassic And Upper Cretaceous Clastic Rocks Of The Eastern Pontides, Yusufeli (Artvin), Ne Turkey, Abdurrahman Dokuz, Erkan Tanyolu Jan 2006

Geochemical Constraints On The Provenance, Mineral Sorting And Subaerial Weathering Of Lower Jurassic And Upper Cretaceous Clastic Rocks Of The Eastern Pontides, Yusufeli (Artvin), Ne Turkey, Abdurrahman Dokuz, Erkan Tanyolu

Turkish Journal of Earth Sciences

An integrated petrographic and geochemical study of the shales and sandstones of Early Jurassic and Late Cretaceous age in the Yusufeli area (Turkey) was carried out to obtain more information on their provenance, sedimentological history and tectonic setting, as well as to evaluate the influence of weathering, hydraulic sorting and recycling processes upon source-rock signature. Depending on their matrix and mineralogical content, the Lower Jurassic sandstones are identified as arkosic arenite and wacke, while the Upper Cretaceous sandstones are defined as lithic arenite and wacke. Elemental ratios such as La/Sc, Cr/Ni, Co/Th, Th/Sc and Cr/Th indicate a mafic source for …


Calcretized Ferricretes Around The Jaisalmer Area, Thar Desert, India: Their Chemistry, Mineralogy, Micromorphology And Genesis, D. Ramakrishnan, Krishna Chandra Tiwari Jan 2006

Calcretized Ferricretes Around The Jaisalmer Area, Thar Desert, India: Their Chemistry, Mineralogy, Micromorphology And Genesis, D. Ramakrishnan, Krishna Chandra Tiwari

Turkish Journal of Earth Sciences

Ferricrete, an iron duricrust, caps Tertiary and Mesozoic rocks around Jaisalmer in the Indian desert. These ferricretes are associated with two distinct present-day landforms. The upper unit is a high-level dissected, rocky structural plain and the lower one a colluvial flat with soft ferricrete gravels. This study pertains to the first situation wherein field observations, micromorphological features and regolith chemistry suggest an in situ origin for the ferricretes, as in the case of the Walther profile. Subsequent tectonism and changes in base level resulted in a shift in processes from weathering to erosion. Episodes of erosion resulted in inversion of …


The Impact Of Polyacrylamide Molecular Weight On Its Adsorption Behavior At The Gold/Acidic Solution Interface, Dragica B. Chamovska, Toma P. Grchev, Maja V. Cvetkovska Jan 2006

The Impact Of Polyacrylamide Molecular Weight On Its Adsorption Behavior At The Gold/Acidic Solution Interface, Dragica B. Chamovska, Toma P. Grchev, Maja V. Cvetkovska

Turkish Journal of Chemistry

Adsorption isotherms for polyacrylamide (PAA) on polycrystalline gold, from sulfuric acid (potential range 0-2.0 V/she; 293 K), were obtained by means of cyclic voltammetry with simultaneous monitoring of the double-layer capacity. The Frumkin isotherm indicates that relatively strong attractive forces are present (a = 0.8-1.0), and the Gibbs energies range between 43 and 56 kJ mol^{-1}. The coverage (\theta) of the metal surface with polymer molecules depends on the molar concentration of PAA, as well as on its molecular weight, and the size of the statistical polymer coil in the solution (R_G = 7.49 \times 10^{-3} \times M_n^{0.64}/nm). The adsorption …


The Mechanism And Crystal Structure Of 2-Methoxy-2-Methyl-4-Phenyl-3,4,4a, 10b-Tetrahydro-2h,5h-Pyrano[3,2-C]Chromen-5-One. Acetal Of Warfarin Acid, Saira Shahzadi, Saqib Ali, Irum Asif, Rizwana Ashraf, Guo-Xin Jin Jan 2006

The Mechanism And Crystal Structure Of 2-Methoxy-2-Methyl-4-Phenyl-3,4,4a, 10b-Tetrahydro-2h,5h-Pyrano[3,2-C]Chromen-5-One. Acetal Of Warfarin Acid, Saira Shahzadi, Saqib Ali, Irum Asif, Rizwana Ashraf, Guo-Xin Jin

Turkish Journal of Chemistry

Acetal of warfarin acid has been synthesized via a hemi acetal intermediate and structurally characterized by X-ray diffraction. The crystal structure shows that the title compound was formed by the hydrolysis of warfarin acid in methanol at pH 3, with space group P2_1/n and unit cell parameters a = 5.859 (17), b =16.745 (5), c = 16.402 (5) Å, \alpha = 90.00; \beta = 94.853 (4), and \gamma = 90.00°.


Cerium(Iii) Ion-Selective Electrodes Based On 1,4,7-Trithiacyclononane, Hamid Reza Pouretedal, Abolfazl Semnani, Mohammad Hossein Keshavarz Jan 2006

Cerium(Iii) Ion-Selective Electrodes Based On 1,4,7-Trithiacyclononane, Hamid Reza Pouretedal, Abolfazl Semnani, Mohammad Hossein Keshavarz

Turkish Journal of Chemistry

Novel plasticized polymeric membrane (PPME) and coated platinum wire (CPWE) electrodes based on 1,4,7-trithiacyclononane and oleic acid, as a good lipophilic additive for highly selective determination of Ce^{3+} ions, have been developed. The electrodes exhibit a Nernstian slope of 19.4 mV/decade (for both electrodes) over a wide Ce^{3+} ion concentration range, from 5.0 \times 10^{-6}-5.0 \times 10^{-2} M and 1.0 \times 10^{-7}-1.0 \times 10^{-2} M for PPME and CPWE, respectively. The limits of detection were 3.5 \times 10^{-6} and 8.0 \times 10^{-8} M for PPME and CPWE, respectively. The electrodes possess a fast response time of 15 s, can be …


Synthesis And Properties Of Triazol-5-One Substituted Phthalocyanines By Microwave Irradiation, Bahatti̇n Kahveci̇, Selami̇ Şaşmaz, Musa Özi̇l, Ci̇han Kantar, Başak Koşar, Orhan Büyükgüngör Jan 2006

Synthesis And Properties Of Triazol-5-One Substituted Phthalocyanines By Microwave Irradiation, Bahatti̇n Kahveci̇, Selami̇ Şaşmaz, Musa Özi̇l, Ci̇han Kantar, Başak Koşar, Orhan Büyükgüngör

Turkish Journal of Chemistry

Triazol-5-one substituted phthalocyanines were prepared quickly by the reaction of 4-nitrophthalonitrile with anhydrous metal salts in DBU (1,8-diazabicyclo[5,4,0]undec-7-ene) and DMAE (dimethylaminoethanol) by microwave irradiation. Microwave yields were higher than those of the conventional synthesis methods. All of these complexes are insoluble in polar solvents such as ethanol, ethyl acetate and chloroform. The characterization of the compounds was accomplished by elemental analysis, ^1H NMR (for I and II), ^{13}C NMR (for I and II), IR and UV-Vis spectral data. In addition, the structure of the starting material (I) was determined by single crystal diffraction.


Synthesis, Spectroscopic (Ft-Ir, ^1h, ^{13}C, Mass Spectrometry), And Biological Investigation Of Five-Coordinated Germanium-Substituted Tricyclohexyl Antimony Dipropionates: Crystal Structure Of Tricyclohexylantimony Dibromide, Muhammad Kaleem Khosa, Muhammad Mazhar, Saqib Ali, Kieran C. Molloy, Sarim Dastgir, Farkhanda Shaheen Jan 2006

Synthesis, Spectroscopic (Ft-Ir, ^1h, ^{13}C, Mass Spectrometry), And Biological Investigation Of Five-Coordinated Germanium-Substituted Tricyclohexyl Antimony Dipropionates: Crystal Structure Of Tricyclohexylantimony Dibromide, Muhammad Kaleem Khosa, Muhammad Mazhar, Saqib Ali, Kieran C. Molloy, Sarim Dastgir, Farkhanda Shaheen

Turkish Journal of Chemistry

A series of five-coordinated germanium-substituted tricyclohexylantimony dipropionates have been synthesized and characterized by different instrumental techniques, such as elemental analyses, FT-IR, multinuclear NMR (^1H, ^{13}C) and mass spectrometry. These compounds have also been screened against different microbes and they showed good activity against different bacteria that was comparable to the reference drugs. The crystal structure of the precursor (C_6H_{11})_3SbBr_2 is reported here, which showed that the antimony atom in an asymmetric unit exists in trigonal bipyramidal geometry, having space group C2/c with the monoclinic crystal system.


Cambrian Stratigraphy And Trilobites Of The Samur Dağ Area, South Of Hakkâri, Southeastern Turkey, William T. Dean Jan 2006

Cambrian Stratigraphy And Trilobites Of The Samur Dağ Area, South Of Hakkâri, Southeastern Turkey, William T. Dean

Turkish Journal of Earth Sciences

Carbonates of the higher Koruk Formation at Yayla Tepe, near the Samur Dağ in southeastern Turkey and about 17 km north of the Iraq border, contain peri-Gondwanan Middle Cambrian trilobites typical of the Mediterranean Subprovince; these comprise at least seven genera and include the easternmost records in the Near and Middle East of Eccaparadoxides and the biozonal genus Pardailhania. In the lower half of the succeeding, largely clastic Seydişehir Formation, Upper Cambrian trilobites from six levels in decalcified limestone interbeds include four new species [Coosinoides parthianus, Elegantaspis? montis, Prochuangia turcica, Taishania bassifrons] in addition to Chuangia? sp. and Palaeadotes sp. …


Palynomorph, Foraminifera, And Calcareous Nannoplankton Biostratigraphy Of Oligo–Miocene Sediments In The Muş Basin, Eastern Anatolia, Turkey, Recep Hayretti̇n Sancay, Zühtü Bati, Uğraş Işik, Sabri̇ Kirici, Ni̇hal Akça Jan 2006

Palynomorph, Foraminifera, And Calcareous Nannoplankton Biostratigraphy Of Oligo–Miocene Sediments In The Muş Basin, Eastern Anatolia, Turkey, Recep Hayretti̇n Sancay, Zühtü Bati, Uğraş Işik, Sabri̇ Kirici, Ni̇hal Akça

Turkish Journal of Earth Sciences

Oligo-Miocene sediments have not been adequately studied biostratigraphically, and a detailed bio-chronostratigraphic framework has not yet been established in Eastern Anatolian basins. Palynomorphs have therefore been correlated with the biozonations of marine dinoflagellates, planktonic foraminifera and calcareous nannoplankton of similar latitudes in combined samples from the Ebulbahar and Kelereşdere measured stratigraphic sections, which are located in the northeastern part of Muş. Palynological (dinoflagellate), foraminiferal micropalaentological, and nannopalaeontological events, correlatable with worldwide defined biozonations, have been documented from uppermost Rupelian to Upper Miocene-Pliocene sediments. First occurrences (FOs) and and last occurrences (LOs) of selected dinoflagellates are important in establishing the biostratigraphic …


Synthesis And Anticancer Evaluation Of Some New Unsymmetrical 3,5-Diaryl-4h-1,2,4-Triazole Derivatives, Olcay Beki̇rcan, Bahi̇tti̇n Kahveci̇, Murat Küçük Jan 2006

Synthesis And Anticancer Evaluation Of Some New Unsymmetrical 3,5-Diaryl-4h-1,2,4-Triazole Derivatives, Olcay Beki̇rcan, Bahi̇tti̇n Kahveci̇, Murat Küçük

Turkish Journal of Chemistry

A series of 4-arylidenamino-4H-1,2,4-triazole derivatives (3-11) were synthesized from the treatment of 4-amino-4H-1,2,4-triazoles (2) with certain aldehydes. Compounds 3-11 were reduced with NaBH_4 to afford the corresponding 4-arylmethylenamino-4H-1,2,4-triazoles (12-20). Compounds 1-10 and 12-19 were characterized by elemental analyses and ^1H NMR, ^{13}C NMR, IR and UV spectral data. Compounds 11 and 20 were characterized by ^1H NMR, ^{13}C NMR, IR and mass spectral data. Compounds 14, 16, 17, and 18 were tested for anticancer activities. Compound 17, chosen for its higher anticancer activity in the preliminary tests with the cancer cell lines of MCF7, NCI-H460, and SF-268, exhibited remarkable anticancer …


Synthesis And Characterization Of Metal Complexes Of Cu(Ii), Ni(Ii), Zn(Ii), Co(Ii), Mn(Ii) And Cd(Ii) With Tetradentate Schiff Bases, Jianning Liu, Bo-Wan Wu, Bing Zhang, Yongchun Liu Jan 2006

Synthesis And Characterization Of Metal Complexes Of Cu(Ii), Ni(Ii), Zn(Ii), Co(Ii), Mn(Ii) And Cd(Ii) With Tetradentate Schiff Bases, Jianning Liu, Bo-Wan Wu, Bing Zhang, Yongchun Liu

Turkish Journal of Chemistry

4-(Benzeneazo)salicylaldehyde was synthesized with aniline, sodium nitrite and salicylaldehyde. Two tetradentate ligands, N,N'-bis[4-(benzeneazo) salicylaldehyde]-o-phenylenediamine (H_2L) and N,N'-bis[4-(benzeneazo) salicylaldehyde]ethylenediamine (H_2L') were formed by the 2:1 molar condensation of 4-(benzeneazo) salicylaldehyde with o-phenylenediamine or ethylenediamine. Their Cu(II), Ni(II), Zn(II), Co(II), Mn(II) and Cd(II) complexes were synthesized and characterized by elemental analysis, molar conductivity measurements, and infrared and electronic spectral data. Two ligands and their Ni(II) and Zn(II) complexes were further identified using ^1H NMR spectra. The results suggest that the metal is bonded to the ligand through the phenolic oxygen and the imino nitrogen.


Kinetics And Mechanism Of Oxidation Of 1,3--Butylene Glycol By Dihydroxyditellutoargentate(Iii) In Alkaline Medium, Jin-Huan Shan, Shu-Ying Huo, Shi-Gang Shen, Han-Wen Sun Jan 2006

Kinetics And Mechanism Of Oxidation Of 1,3--Butylene Glycol By Dihydroxyditellutoargentate(Iii) In Alkaline Medium, Jin-Huan Shan, Shu-Ying Huo, Shi-Gang Shen, Han-Wen Sun

Turkish Journal of Chemistry

The kinetics of oxidation of 1,3--butlene glycol (\beta - BG) by dihydroxyditelluto- argentate(III) were studied spectrophotometrically between 298.2 and 313.2 K in alkaline medium. The reaction rate showed pseudo-first order dependence in oxidant and fractional order in \ss-BG. The pseudo-first order rate constant k_{obs} increased with an increase in the concentration of OH^- and a decrease in the concentration of TeO_4^{2-} . There was a negative salt effect and no free radicals were detected. Thus, the dihydroxymonotelluratoargentate(III) species is assumed to be the active species. The activation parameters along with the rate constants of the rate-determining step were calculated.


A Novel Alkaloid From Stapelia Hirsuta, Marwan Shabana, Mariam Gonaid, Maha Mahmoud Salama, Essam Abdel-Sattar Jan 2006

A Novel Alkaloid From Stapelia Hirsuta, Marwan Shabana, Mariam Gonaid, Maha Mahmoud Salama, Essam Abdel-Sattar

Turkish Journal of Chemistry

A novel alkaloid (1,8,8-trimethyl-5,8-dihydro-1H-pyrano[3,4-b]pyridine-4,6-dione) was isolated from the chloroformic traction obtained from the total alcoholic extract of the aerial parts of Stapelia hirsuta L. In addition, apigenin, luteolin and \beta-sitosterol-3-O-\beta-D- glucopyranoside were also isolated.


Synthesis Of A Ruthenium Complex Bound To A Polyimide Matrix: Investigating The Catalytic Properties In A Hydrosilylation Reaction, Turgay Seçki̇n, Süleyman Köytepe, İsmai̇l Özdemi̇r, Beki̇r Çeti̇nkaya Jan 2006

Synthesis Of A Ruthenium Complex Bound To A Polyimide Matrix: Investigating The Catalytic Properties In A Hydrosilylation Reaction, Turgay Seçki̇n, Süleyman Köytepe, İsmai̇l Özdemi̇r, Beki̇r Çeti̇nkaya

Turkish Journal of Chemistry

3,6-Bis(dimethylamino)acridine(hexamethylbenzene)dichlororuthenium(II) was used as a tricyclic heteroatomic monomer to prepare polyimides from the corresponding dianhyrides by solution condensation. The ruthenium complex monomer was synthesized starting from [RuCl_2(HMB)]_2 and 3-6-bis(dimethylamino)acridine. The polymers had inherent viscosities of 1.77 to 2.11 and were soluble in most polar solvents. The glass transition temperatures were in the range of 204 to 298 °C and the 10% weight loss in the range of 506-626 °C, depending upon the structure of the dianhyride monomer. The catalytic activity of the polyimides tested in a hydrosilylation reaction of acetophenone was up to 90%. Leaching of ruthenium into the reaction …


Structure Of 1-(Thiophen-2-Ylmethyl)-2-(Thiophen-2-Yl)-1h-Benzimidazole, Necmi̇ Dege, Memet Şekerci̇, Süleyman Servi̇, Muharrem Di̇nçer, Ünzi̇le Demi̇rbaş Jan 2006

Structure Of 1-(Thiophen-2-Ylmethyl)-2-(Thiophen-2-Yl)-1h-Benzimidazole, Necmi̇ Dege, Memet Şekerci̇, Süleyman Servi̇, Muharrem Di̇nçer, Ünzi̇le Demi̇rbaş

Turkish Journal of Chemistry

The title compound, C_{16}H_{12}N_2S_2, crystallizes in the monoclinic space group P2_1/n with Z = 4, a = 8.950 (5) Å, b = 9.141 (5) Å, c = 17.429 (5) Å and \beta = 93.638 (5)°. The benzimidazole ring is essentially planar. The crystal structure is stabilized by intermolecular C---H ... N and C---H ... \pi contacts.


Studies On 2-Ethyl-3-Carbmethoxy-4-Aryl-5-Oxo-1,4,5,6,7,8-Hexahydroquinoline Derivatives And Calcium Modulatory Activities, Ci̇hat Şafak, Elvan Doğan, Kevser Erol Jan 2006

Studies On 2-Ethyl-3-Carbmethoxy-4-Aryl-5-Oxo-1,4,5,6,7,8-Hexahydroquinoline Derivatives And Calcium Modulatory Activities, Ci̇hat Şafak, Elvan Doğan, Kevser Erol

Turkish Journal of Chemistry

Twelve new compounds having a 2-ethyl-3-carbmethoxy-4-aryl-5-oxo-1,4,5,6,7,8-hexahydroquinoline structure were synthesized, characterized and screened for their calcium modulatory activities. The calcium antagonistic activities of the compounds were investigated by tests performed on isolated rat ileum and lamb carotid artery. Compounds 1, 4, 8 and 9 showed considerable activity.


Heterocyclic Synthesis Using Nitrilimines: Part 5. Synthesis Of Some Novel Spiro Heterocycles, Hany M. Dalloul, Peter H. Boyle Jan 2006

Heterocyclic Synthesis Using Nitrilimines: Part 5. Synthesis Of Some Novel Spiro Heterocycles, Hany M. Dalloul, Peter H. Boyle

Turkish Journal of Chemistry

A new class of spiro-triazoles (4a-m) were synthesized from the reaction of corresponding nitrilimines 2 with substituted heterocyclic benzoylhydrazones 3 in good yields. The spectral data of the new synthesized compounds are in full agreement with their molecular structure.


Synthesis Of New 3-Pyrrolin-2-One Derivatives, Nezi̇re Saygili, Ayşegül Altunbaş, Akgül Yeşi̇lada Jan 2006

Synthesis Of New 3-Pyrrolin-2-One Derivatives, Nezi̇re Saygili, Ayşegül Altunbaş, Akgül Yeşi̇lada

Turkish Journal of Chemistry

Six new 3-pyrrolin-2-one derivatives were synthesized via the condensation reaction of amino acid esters (2a-f) with 2,5-dimethoxy-2,5-dihydrofurane (1) in acidic medium. This simple one-pot reaction furnished the corresponding pyrrolinones (3a-f) in acceptable yields.


Construction Of A Homonaphthazarin Skeleton And Synthesis Of Hydroquinone-Annelated Cycloheptatriene Derivatives, Emi̇n Şengül, Abdullah Menzek, Meti̇n Balci Jan 2006

Construction Of A Homonaphthazarin Skeleton And Synthesis Of Hydroquinone-Annelated Cycloheptatriene Derivatives, Emi̇n Şengül, Abdullah Menzek, Meti̇n Balci

Turkish Journal of Chemistry

1,4-Dihydroxy-7,8-dihydro-5H-benzo[a]cycloheptene-5,9(6H)- dione (7) was synthesised from hydroquinone and glutaric acid chloride via an acylation reaction. The reaction of dione (7) with bromine followed by treatment with NEt_3 gave homonaphthazarin 8 as well as the brominated derivatives 9 and 10. Reduction of 1,4-dimethoxy-7,8-dihydro-5H-benzo[a]cycloheptene-5,9(6H)-dione (16) with LiAlH_4 gave 2 isomeric alcohols, 17 and 18. Reaction of these alcohols with SOCl_2 followed by HCl elimination with NEt_3 afforded dimethoxybenzocycloheptatriene 19 as the sole product. For the synthesis of the isomeric cycloheptatriene 20, the double bond in 19 was isomerised with KOt-Bu.


Synthesis Of N-Alkylnaphthalenes Via Semicarbazones, Gülay Zengi̇n, John W. Huffman Jan 2006

Synthesis Of N-Alkylnaphthalenes Via Semicarbazones, Gülay Zengi̇n, John W. Huffman

Turkish Journal of Chemistry

A number of 1-n-alkylnaphthalenes were prepared via the respective semicarbazones. The semicarbazones were reduced by modified Wolff-Kishner reductions to give 1-n-alkylnaphthalenes in excellent yields as manageable yellow or orange viscous oils. The semicarbazones were prepared from ketones, which are the addition products of Grignard reagents to nitriles. This study offers an excellent preparative method for the synthesis of 1-n-alkylnaphthalenes from semicarbazones, via a 3-step procedure.


Formation Of Yttrium(Iii) Complexes With Salicylic Acid Derivatives In Aqueous Solution, Rahmi̇ye Aydin, Ulvi̇ye Özer Jan 2006

Formation Of Yttrium(Iii) Complexes With Salicylic Acid Derivatives In Aqueous Solution, Rahmi̇ye Aydin, Ulvi̇ye Özer

Turkish Journal of Chemistry

Complexes of yttrium(III) formed with 5-sulphosalicylic acid, 5-SSA (H_3L), and 5-nitrosalicylic acid, 5-NSA (H_2L), were investigated in 0.1 mol.dm^{-3} sodium perchlorate ionic medium at 25.0 \pm 0.1 °C potentiometrically for various molar ratios of Y(III) to these salicylic acid, SA (H_2L), derivatives. Y(III) forms YL and YL_2^{3-} type complexes with 5-SSA that have rather high stabilities (log \beta _1 = 7.91 \pm 0.01 and log \beta _2 = 14.56 \pm 0.06). In the Y(III):5-NSA system, YL^+ and YL_2^- type complexes appear with high stabilities (log \beta _1 = 7.39 \pm 0.02 and log \beta _2 = 13.50 \pm 0.07). Y(III):5-SSA …


Rheology Of Polyaniline Dispersions In Acrylic Resin, Nicoleta Plesu, Smaranda Iliescu, Gheorghe Ilia, Adriana Popa, Cornelia Muntean Jan 2006

Rheology Of Polyaniline Dispersions In Acrylic Resin, Nicoleta Plesu, Smaranda Iliescu, Gheorghe Ilia, Adriana Popa, Cornelia Muntean

Turkish Journal of Chemistry

Acrylic dispersions based on polyaniline were obtained and characterised. The polyaniline was obtained by chemical polymerisation of aniline in different organic acid containing phosphorous, in the presence of ammonium-peroxidisulphate as oxidant agent. The blends were obtained by mechanical dispersion of polyaniline in commercially available acrylic resin. The flow behaviour of these dispersions at different shear rates was studied. Furthermore, the resulting acrylic dispersions were analysed by IR spectroscopy, and were characterised in terms of their electrical resistance and rheological behaviour


Heterogeneous Electron Transfer Rate Constants Of Viologen Monocations At A Platinum Disk Electrode, Naheed Kaukab Bhatti, M. Sadiq Subhani, Ather Yaseen Khan, Rumana Qureshi, Abdur Rahman Jan 2006

Heterogeneous Electron Transfer Rate Constants Of Viologen Monocations At A Platinum Disk Electrode, Naheed Kaukab Bhatti, M. Sadiq Subhani, Ather Yaseen Khan, Rumana Qureshi, Abdur Rahman

Turkish Journal of Chemistry

Experimental values of rate constants for the heterogeneous transfer of electrons to methyl viologen, diquat viologen, benzyl viologen and n-butyl viologen monocations were determined. The process was studied at the surface of a platinum disk in mixtures of water with different aprotic solvents at different temperatures. Theoretical rate constants were evaluated using Marcus' equation, which also contains barrier crossing probability and nuclear frequency. A comparison was made between the theoretical and experimental values of rate constants.


Surface Modification Of Glass Beads With An Aminosilane Monolayer, Gülşi̇n Arslan, Mustafa Özmen, Beni̇z Gündüz, Xunli Zhang, Mustafa Ersöz Jan 2006

Surface Modification Of Glass Beads With An Aminosilane Monolayer, Gülşi̇n Arslan, Mustafa Özmen, Beni̇z Gündüz, Xunli Zhang, Mustafa Ersöz

Turkish Journal of Chemistry

Surface modification of glass beads with a self-assembled monolayer of (3-Aminopropyl)-triethoxysilane (APTES) was investigated. Characterisation of the self-assembled monolayer was confirmed by a reaction between amine terminal groups and thionylchloride of Rhodamine-B dye using fluorescence microscopy. Quantitative 3-dimensional profiling was obtained for all modification processes by converting microscopic images to numerical values. The reaction steps were also analysed using infrared spectroscopy (FTIR).


Optimization Of The Nonaqueous Capillary Electrophoresis Separation Of Metal Ions Using Mixture Design And Response Surface Methods, Cevdet Demi̇r, Yasi̇n Yücel Jan 2006

Optimization Of The Nonaqueous Capillary Electrophoresis Separation Of Metal Ions Using Mixture Design And Response Surface Methods, Cevdet Demi̇r, Yasi̇n Yücel

Turkish Journal of Chemistry

Mixture experimental design was used to enhance the separation selectivity of metal ions in nonaqueous capillary electrophoresis. The separation of cations (Ag, Fe, Cr, Mn, Cd, Co, Pb, Ni, Zn and Cu) was achieved using imidazole as UV co-ion for indirect detection. Acetic acid was chosen as an electrolyte because its cathodic electroosmotic flow permits faster separation. The composition of organic solvents is important to achieve the best separation of all metal ions. Simplex lattice design and response surface methods have proved to be an effective tool to optimize the composition of organic solvents in nonaqueous capillary electrophoresis. Full and …


Surface Properties And Catalytic Performance Of Pt/Prsrcoo_4 Catalysts For No Reduction By Co, Hua Zhong, Xirui Zeng Jan 2006

Surface Properties And Catalytic Performance Of Pt/Prsrcoo_4 Catalysts For No Reduction By Co, Hua Zhong, Xirui Zeng

Turkish Journal of Chemistry

Perovskite-type Pr_{2-x}Sr_xCoO_{4\pm \lambda} mixed oxides were prepared by different calcination temperatures and were investigated by XRD, BET, TPD, TPR and XPS methods. These catalysts possess high catalytic activities towards the NO reduction by CO, and the activity of the PrSrCoO_4 catalyst prepared by calcining at 750 °C is the best among these samples. This is explained in terms of its greater oxygen vacancies and larger BET surface areas. The influence of modification by a suitable amount of Pt-doping on the surface properties and catalytic activity for NO reduction by CO was studied. The results show that the Pt-modified PrSrCoO_4 catalysts …


Synthesis And Antifungal Properties Of Some Benzimidazole Derivatives, Gülgün Ayhan Kilcigi̇l, Nurten Altanlar Jan 2006

Synthesis And Antifungal Properties Of Some Benzimidazole Derivatives, Gülgün Ayhan Kilcigi̇l, Nurten Altanlar

Turkish Journal of Chemistry

Some benzimidazole derivatives were synthesized and their in vitro antifungal activities were tested against Candida albicans, Candida glabrata and Candida krusei. Compounds 6 and 9 possessed activity comparable to fluconazole against C. albicans with a minimum inhibitory concentration of 12.5 \mu g/mL.


Sesquiterpene Lactones From Centaurea Helenioides Boiss, Nuretti̇n Yayli, Cemaletti̇n Baltaci, Yaşar Gök, Ebru Aydin, Osman Üçüncü Jan 2006

Sesquiterpene Lactones From Centaurea Helenioides Boiss, Nuretti̇n Yayli, Cemaletti̇n Baltaci, Yaşar Gök, Ebru Aydin, Osman Üçüncü

Turkish Journal of Chemistry

Grosheimin (1) and cynaropicrin (3) sesquiterpenes were isolated from the flowers of Centaurea helenioides Boiss., an endemic plant of Turkey. The products are known as they occur in another species, but they were isolated and identified for the first time from C. helenioides Boiss. In order to correlate spectral data of grosheimin, its acetyl derivative, 8\alpha -acetyl grosheimin (2) was also prepared. Their structures were deduced by FT-IR, UV, 1D and 2D NMR, LC MS/MS, GC-mass spectra (EI), optical rotation, and chemical methods.


Synthesis And Crystal Structure Of 1,3-Bis(5-Formylpyrrol-2-Yl)Benzene And Its Conversion To A Macrocyclic Derivative, M. Kasim Şener, Davi̇d Sanches Garcia, Mehmet Akkurt, Sema Öztürk Yildirim, Hoong-Kun Fun, Jonathan L. Sessler Jan 2006

Synthesis And Crystal Structure Of 1,3-Bis(5-Formylpyrrol-2-Yl)Benzene And Its Conversion To A Macrocyclic Derivative, M. Kasim Şener, Davi̇d Sanches Garcia, Mehmet Akkurt, Sema Öztürk Yildirim, Hoong-Kun Fun, Jonathan L. Sessler

Turkish Journal of Chemistry

This report details the synthesis and characterization of a new diformyl pyrrole derivative 2 and its macrocyclic derivative 3. The new compounds were characterized by FT-IR, ^{13}C NMR, and ^1H NMR spectroscopies and via mass spectrometric analysis. The structure of 2 in the solid state was determined using X-ray diffraction methods (monoclinic, P2_1/c, a = 17.3760(7), b = 4.9719(2), c = 15.5374(5) Å, \beta = 105.892(2) °, V = 1291.00(9) Å^3, and Z = 4). The molecular structure is stabilized by N-H...O and C-H...O intermolecular hydrogen bonds. The present bisformylpyrrole derivative 2 provides a new precursor that may be useful …


Gc-Ms Analysis And Antibacterial Activity Of Cultivated Satureja Cuneifolia Ten. Essential Oil, Yüksel Kan, Uçkun Sai̇t Uçan, Murat Kartal, M. Levent Altun, Si̇nem Aslan, Esi̇n Sayar, Ti̇murhan Ceyhan Jan 2006

Gc-Ms Analysis And Antibacterial Activity Of Cultivated Satureja Cuneifolia Ten. Essential Oil, Yüksel Kan, Uçkun Sai̇t Uçan, Murat Kartal, M. Levent Altun, Si̇nem Aslan, Esi̇n Sayar, Ti̇murhan Ceyhan

Turkish Journal of Chemistry

The composition of the essential oil of Satureja cuneifolia Ten. cultivated in Konya, Turkey, was investigated by capillary GC-MS. The compounds were characterized by comparison with library searches. Six main compounds were identified. Carvacrol was the dominant component, comprising 59.28% of the essential oil. The oil also contained 15.72% thymol, 9.69% p-cymene, 4.16% \gamma -terpinene, 1.70% linalool and 1.25% borneol. The antibacterial activity of the essential oil of S. cuneifolia and its components was determined by a semiquantative disc-diffusion method, and the minimum inhibitory concentration (MIC) was determined based on a micro-well dilution method against strains of Pseudomonas aeruginosa, Bacillus …