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Full-Text Articles in Physical Sciences and Mathematics

Retention And Transport Of Hexavalent Chromium In Calcareous Karst Soils, İrfan Yolcubal, Ni̇hat Hakan Akyol Jan 2007

Retention And Transport Of Hexavalent Chromium In Calcareous Karst Soils, İrfan Yolcubal, Ni̇hat Hakan Akyol

Turkish Journal of Earth Sciences

Hexavalent chromium, which is a highly toxic and soluble form of the element chromium, is a common soil and groundwater contaminant found in many contaminated sites throughout the world and poses a serious risk to human health when released into environment. The objective of this study was to determine transport and retention behaviour of aqueous Cr(VI) species in a highly calcareous and alkaline top soil of a karst system that is vulnerable to contamination. Batch sorption studies and column experiments conducted at both saturated and unsaturated steady-state flow conditions were used to evaluate the sorption/desorption and the transport of Cr(VI) …


Filograna Minor Nov. Sp. (Worm Tube) From The Middle Triassic (Anisian) Reef Boulders Of The Karaburun Peninsula, Western Turkey, Baba Senowbari-Daryan, Michael Link, İsmai̇l Işintek Jan 2007

Filograna Minor Nov. Sp. (Worm Tube) From The Middle Triassic (Anisian) Reef Boulders Of The Karaburun Peninsula, Western Turkey, Baba Senowbari-Daryan, Michael Link, İsmai̇l Işintek

Turkish Journal of Earth Sciences

A colonial serpulid worm tube, Filograna minor nov. sp., from the Anisian reef boulders of the Karaburun Peninsula, Western Turkey is described. The Filograna-bearing boulders occur together with Anisian reef boulders within the Upper Anisian siliciclastic deposits of the Gerence Formation. Filograna minor differs from the Norian species Filograna serialis, described by Senowbari-Daryan and Link from the Taurus Mountains, by the smaller dimensions of the tubes.


Intracontinental Quaternary Volcanism In The Niksar Pull-Apart Basin, North Anatolian Fault Zone, Turkey, Orhan Tatar, Sema Yurtmen, Haluk Temi̇z, Hali̇l Gürsoy, Fi̇kret Koçbulut, B. Levent Mesci̇, Jean Claude Guezou Jan 2007

Intracontinental Quaternary Volcanism In The Niksar Pull-Apart Basin, North Anatolian Fault Zone, Turkey, Orhan Tatar, Sema Yurtmen, Haluk Temi̇z, Hali̇l Gürsoy, Fi̇kret Koçbulut, B. Levent Mesci̇, Jean Claude Guezou

Turkish Journal of Earth Sciences

The Niksar Basin is sited along the eastern segment of the North Anatolian Fault Zone in Turkey. It is a young sigmoidal pull-apart basin bordered by two non-parallel master faults associated with earthquakes in 1939 and 1942. The fault geometry along the irregular ENE margin of the basin is complex where young Plio-Quaternary volcanic rocks reach the surface along pairs of steep strike-slip faults which cut the basin sediments. The volcanic rocks around the Niksar Basin have been dated by high precision K-Ar dating and the ages range between 542 ± 9 ka and 567 ± 9 ka. The lavas …


Tectonic Evolution Of The Kiraz Basin, Küçük Menderes Graben: Evidence For Compression/Uplift-Related Basin Formation Overprinted By Extensional Tectonics In West Anatolia, Tahi̇r Emre, Hasan Sözbi̇li̇r Jan 2007

Tectonic Evolution Of The Kiraz Basin, Küçük Menderes Graben: Evidence For Compression/Uplift-Related Basin Formation Overprinted By Extensional Tectonics In West Anatolia, Tahi̇r Emre, Hasan Sözbi̇li̇r

Turkish Journal of Earth Sciences

The Kiraz Basin which is located at the eastern end of the Küçük Menderes Graben was previously considered to be an extensional basin. However, the data presented here allow us to infer that the tectonic evolution of the Kiraz Basin could be explained by an alternate model which suggests compression/uplift-related basin formation at the early stage of basin evolution followed, later, by block faulting in an extensional neotectonic regime. The successive compressional and extensional strain is accommodated by a predominantly NE-trending strike-slip fault system. The new model is based on the detailed mapping, field-cross sections and kinematic analyses of the …


Quaternary Activity Of The Cihanbeyli And Yeniceoba Fault Zones: İnönü-Eskişehir Fault System, Central Anatolia, Erman Özsayin, Kadi̇r Di̇ri̇k Jan 2007

Quaternary Activity Of The Cihanbeyli And Yeniceoba Fault Zones: İnönü-Eskişehir Fault System, Central Anatolia, Erman Özsayin, Kadi̇r Di̇ri̇k

Turkish Journal of Earth Sciences

The İnönü-Eskişehir fault system (İEFS) is one of the most important fault systems in Central Anatolia and consists of a series of NW-SE- to WNW-ESE-trending fault zones extending from Uludağ (Bursa) in the northwest to Sultanhanı in the southeast. Between İnönü and Sivrihisar, the Eskişehir fault zone of the İEFS trends WNW, but east of Sivrihisar the İEFS changes its direction to NW-SE and splays out into four fault zones, named the Ilıca, Yeniceoba, Cihanbeyli and Sultanhanı fault zones and extends to south of Tuzgölü in the east. The NW-SE-trending Yeniceoba fault zone (YFZ), exposed between Günyüzü in the west …


The Dikili-Çandarlı Volcanics, Western Turkey: Magmatic Interactions As Recorded By Petrographic And Geochemical Features, Zeki̇ye Karacik, Yücel Yilmaz, Julian A. Pearce Jan 2007

The Dikili-Çandarlı Volcanics, Western Turkey: Magmatic Interactions As Recorded By Petrographic And Geochemical Features, Zeki̇ye Karacik, Yücel Yilmaz, Julian A. Pearce

Turkish Journal of Earth Sciences

Located in the northwestern part of the Aegean region, Dikili-Çandarlı volcanic suite contains products representative for the western Anatolian Miocene volcanism. They can be divided into two main groups: the Dikili and the Çandarlı groups. The Dikili group is Early-Middle Miocene in age and consists mainly of pyroclastic rocks, andesitic-dacitic lavas, lava breccia, lahar flows and associated sedimentary rocks. The lavas contain disequilibrium phenocrysts assemblages. The Çandarlı group consists of Upper Miocene-Pliocene lava and sediment associations. The volcanic rocks consist mainly of rhyolitic domes and basaltic trachyandesite-basaltic andesite lavas erupted along the NW-SE- and NE-SW-trending fault systems; the faults controlled …


Jurassic Volcanism In The Eastern Pontides: Is It Rift Related Or Subduction Related?, Cüneyt Şen Jan 2007

Jurassic Volcanism In The Eastern Pontides: Is It Rift Related Or Subduction Related?, Cüneyt Şen

Turkish Journal of Earth Sciences

The Jurassic volcanic rocks in the centre of the northern zone (south of Trabzon City) provide important constraints on the evolution of Pontides. The investigated volcanic rocks form a transitional series between tholeiitic and calc-alkaline, and is dominated by basalt, basaltic andesite and andesite. Geochemically, they are enriched in LILE and LREE contents and depleted in HFSE [(La/Yb)_N= 2.2 - 8.5; (Nb/La)_N= 0.1 - 0.77)] compared to mid-ocean ridge basalts and have radiogenic Nd isotope ratios of \epsilonNd(210 Ma)= -0.72 to 3.24. These trace element and isotope data suggest that these rocks were derived from low degrees of partial melting …


Electronic Structure Of Surfaces In Gese Layered Semiconductor, Z. A. Jahangirli, M. Z. Zarbaliyev Jan 2007

Electronic Structure Of Surfaces In Gese Layered Semiconductor, Z. A. Jahangirli, M. Z. Zarbaliyev

Turkish Journal of Physics

Green´s function method in bases sets of Linear Combinations of Atomic Orbitals (LCAO) is used to calculate the electronic structure of the (010) surface of GeSe semiconductor. The energy states in energy gaps, their origin, orbital content, resonances and local changes in the density of states due to the surface are discussed.


A 3-D Hall Sensor For Precise Angular Position Measurements, Konstantin Veselinov Dimitrov Jan 2007

A 3-D Hall Sensor For Precise Angular Position Measurements, Konstantin Veselinov Dimitrov

Turkish Journal of Physics

A 3-D silicon Hall effect sensor for precise angular-position measurement over 360° rotation is presented. This vector microtransducer functionally integrates into a common sensor region two parallel-field Hall devices for in-plane components of the magnetic field and one orthogonal Hall version for the perpendicular for the chip magnetic field. The advantages of this magnetometer are its low channel cross-sensitivities, remarkable simplified device design and high spatial resolution.


Green Function Of The Morse Potential Using Perturbation Series, B. Boudjedaa, M. T. Meftah, Lyazid Chetouani Jan 2007

Green Function Of The Morse Potential Using Perturbation Series, B. Boudjedaa, M. T. Meftah, Lyazid Chetouani

Turkish Journal of Physics

We find the Green function of the Schrodinger equation for the Morse potential using perturbation series. By Fourier transformation on the end point of the perturbation series, and with some formulas for terms generating the perturbation series, we are able to derive the Green function of the problem.


Longitudinal Form Factor Of Isoscalar Particle-Hole States In ^{16}O, ^{12}C And ^{40}Ca With M3y Interaction, Ali H. Taqi, Raad A. Radhi Jan 2007

Longitudinal Form Factor Of Isoscalar Particle-Hole States In ^{16}O, ^{12}C And ^{40}Ca With M3y Interaction, Ali H. Taqi, Raad A. Radhi

Turkish Journal of Physics

Longitudinal form factors of the low-lying, T = 0, particle-hole states of ^{16}O, ^{12}C and ^{40}Ca are studied in the framework of Random Phase Approximation RPA. The basis of single particle states is considered to include 0s, 0p, 1s-0d and 0f-1p. The Hamiltonion is diagonalized in the presence of Michigan three-rang Yakawa (M3Y) interaction and compared with our previous results depend on Modified Surface Delta Interaction MSDI interaction. Admixture of higher configuration up to 2p-1f is considered for the ground state. Effective charges are used to account for the core polarization effect. Comparisons are made to experimental data where available …


Photovoltaic Properties Of N-(Zns)_X(Cdte)_{1-X}/P-Si, S. K. J. Al-Ani, A. Kh. Ba-Yashoot, M. N. Makadsi, A. M. Al-Sharbaty Jan 2007

Photovoltaic Properties Of N-(Zns)_X(Cdte)_{1-X}/P-Si, S. K. J. Al-Ani, A. Kh. Ba-Yashoot, M. N. Makadsi, A. M. Al-Sharbaty

Turkish Journal of Physics

Hetrojunction solar cells n-(ZnS)_{x}(CdTe)_{1-x}/p-Si, with Al, In and Au as front grid contacts, have been fabricated by thermal evaporation technique. Their photovoltaic properties and the forward I-V characteristics of the annealed cells at 400 °C were studied. The efficiency, ideality factor and other parameters have been obtained. The results showed that the efficiency, as well as the ideality factor, depends on the ZnS content in the cell and the efficiency is high for Au front contact compared with that of Al and In.


Catalytic Processes For Clean Hydrogen Production From Hydrocarbons, Zeynep İlsen Önsan Jan 2007

Catalytic Processes For Clean Hydrogen Production From Hydrocarbons, Zeynep İlsen Önsan

Turkish Journal of Chemistry

Conversion of hydrocarbon fuels to hydrogen with a high degree of purity acceptable for fuel cell operation presents interesting challenges for the design of new selective catalysts and catalytic processes. Natural gas, LPG, gasoline, and diesel are regarded as promising hydrocarbon fuels. Methanol has received attention despite its toxicity, and ethanol has recently become of interest as a much less toxic and renewable resource. Selective catalytic processes considered for commercial use are based on steam reforming and partial oxidation of these fuels. Autothermal reforming (ATR) or indirect partial oxidation (IPOX) combines total oxidation (TOX), steam reforming (SR), and water-gas shift …


Characterization And Co Oxidation Activity Studies Of Co-Based Catalysts, Fi̇li̇z Balikçi, Çi̇ğdem Güldür Jan 2007

Characterization And Co Oxidation Activity Studies Of Co-Based Catalysts, Fi̇li̇z Balikçi, Çi̇ğdem Güldür

Turkish Journal of Chemistry

Cobalt oxide based catalysts were developed for carbon monoxide oxidation at low temperature. The catalysts were prepared by co-precipitation and calcined at 200 °C. Several techniques were used to characterize the catalysts, such as X-ray diffractometer system, N_2 physisorption measurements, scanning electron microscope (SEM), and X-ray photoelectron spectroscopy. Carbon monoxide oxidation studies were carried out to investigate the relation between the characteristic properties of the catalysts and the catalytic activity. Catalytic activity measurements were studied from room temperature to 200 °C, using a feed composition of 1% CO, 21% O_2, and remaining He. X-ray studies showed that the catalysts have …


Synthesis Of Piperazine Based Polyimide In The Presence Of Ionic Liquids, Bülent Alici, Süleyman Köytepe, Turgay Seçki̇n Jan 2007

Synthesis Of Piperazine Based Polyimide In The Presence Of Ionic Liquids, Bülent Alici, Süleyman Köytepe, Turgay Seçki̇n

Turkish Journal of Chemistry

Ionic liquids derived from imidazolium, pyridinium, and alkylammonium salts were investigated not only as catalysts but also as solvents in polymerization of 1,4-bis(3-aminopropyl) piperazine. Results were compared with the conventional polymerizations in N-methylpyrrolidone (NMP). The catalyst has not only a detectable influence on polymer solubility, but also the degrees of polymerization are notably higher. They are even greater than the values obtained by conventional 2-stage polymerization in organic liquids. Ionic liquids based on imidazolium salts seem preferable over pyridinium and alkylammonium salts due to the higher degree of polydispersity of the polyimides obtained. The glass transition temperatures and thermal stabilities …


The Direct Electrochemical Synthesis Of Ti(Ii), Fe(Ii), Cd(Ii), Sn(Ii), And Pb(Ii) Complexes With N, N´-Bis(Salicylidene)-O-Phenylenediamine, Jianning Liu, Bing Zhang, Bowan Wu, Kejun Zhang, Shenli Hu Jan 2007

The Direct Electrochemical Synthesis Of Ti(Ii), Fe(Ii), Cd(Ii), Sn(Ii), And Pb(Ii) Complexes With N, N´-Bis(Salicylidene)-O-Phenylenediamine, Jianning Liu, Bing Zhang, Bowan Wu, Kejun Zhang, Shenli Hu

Turkish Journal of Chemistry

The electrochemical oxidation of anodic Ti, Fe, Cd, Sn, and Pb (=M) into acetonitrile solutions of N,N'-bis(salicylidene)-o-phenylenediamine [SalophH_2] gives the corresponding M(Saloph) complexes in high yield. The mechanism of the electrochemical reactions is discussed. SalophH_2 forms complexes (1:1 molar ratio) with titanium, iron, cadmium, tin, and lead ions. The complexes have been characterized by elemental analyses, molar conductivity measurements, and infrared and electronic spectral data. The SalophH_2 complexes of iron(II) and cadmium(II) have been further identified by ^1H-NMR and mass spectra.


Synthesis And Characterization Of Nife_2o_4 Nano-Octahedrons By Edta-Assisted Hydrothermal Method, Nermi̇n Kasapoğlu, Abdulhadi̇ Baykal, Muhammet S. Toprak, Yüksel Köseoğlu, Harun Bayrakdar Jan 2007

Synthesis And Characterization Of Nife_2o_4 Nano-Octahedrons By Edta-Assisted Hydrothermal Method, Nermi̇n Kasapoğlu, Abdulhadi̇ Baykal, Muhammet S. Toprak, Yüksel Köseoğlu, Harun Bayrakdar

Turkish Journal of Chemistry

Octahedral-like NiFe_2O_4 ferrite nanocrystals were synthesized using EDTA-assisted hydrothermal method under mild conditions. XRD and FTIR analysis were used for composition and structure investigation. XRD analysis revealed a pure ferrite phase with high crystallinity. Morphological investigation by SEM showed octahedral nanocrystals with an average particle size of \sim 40 nm. Crystallite size calculated from XRD peak broadening resulted in an average crystallite size of 39 nm, matching well with the SEM observations. TEM analysis and corresponding electron diffraction confirmed the octahedral morphology and single crystallinity of octahedral nanoparticles. Magnetic measurements showed that NiFe_2O_4 octahedrons have smaller coercivity than bulk ferrite …


Basic Al_2o_3 As A Recyclable Reagent For The Protection Of Carbonyl Groups With Phenylhydrazine Derivatives And Semicarbazides, Khodabakhsh Niknam, Ali Reza Kiasat, Bahador Karami, Nima Heydari Jan 2007

Basic Al_2o_3 As A Recyclable Reagent For The Protection Of Carbonyl Groups With Phenylhydrazine Derivatives And Semicarbazides, Khodabakhsh Niknam, Ali Reza Kiasat, Bahador Karami, Nima Heydari

Turkish Journal of Chemistry

Basic alumina is employed as an inorganic basic solid catalyst for the clean and less hazardous protection of carbonyl compounds, such as phenylhydrazones, 2,4-dinitrophenylhydrazones, semicarbazones, and thiosemicarbazones, under solvent-free conditions. The reactions proceed smoothly and require a short reaction time with good to excellent yields, and the alumina used can be recycled.


Synthesis And Spectroscopic Characterization Of New [Cu(^{Tbu}Salpphen)]_2, [Mocl_2(Salpphen)]_2 Complexes And Sn_2cl_8(^{Tbu}Salpphen).2hnet_3 Adduct, Peli̇n Sözen, Yurdanur Akgül, Funda Demi̇rhan Jan 2007

Synthesis And Spectroscopic Characterization Of New [Cu(^{Tbu}Salpphen)]_2, [Mocl_2(Salpphen)]_2 Complexes And Sn_2cl_8(^{Tbu}Salpphen).2hnet_3 Adduct, Peli̇n Sözen, Yurdanur Akgül, Funda Demi̇rhan

Turkish Journal of Chemistry

Tetradentate Schiff base ligands, which were derived from the condensation of phenylenediamine with salicylaldehyde [salpphenH_2: N, N'-p-phenylene-bis(salicyclideneimine)] or 3,5-di-tert-butyl-2-hydroxyben- zaldehyde [^{tBu}salpphenH_2: N, N'-p-phenylene-bis(3,5-di-tert-butylsalicylidene)] and their complexes of Cu(II), Mo(IV) and adduct of Sn(IV) were synthesized and characterized by ^1H-NMR, ^{13}C-NMR, and IR spectroscopic methods, mp, elemental analysis, and magnetic susceptibility. According to these data probable structures were assigned to these complexes and adduct. These are of the formula [Cu(^{tBu}salpphen)]_2 and [MoCl_2(salpphen)]_2, and Sn_2Cl_8(^{tBu}salpphen).2HNEt_3. [Cu(^{tBu}salpphen)]_2 was prepared by the reaction of the metal salt with the ^{tBu}salpphenH_2 Schiff base ligand in EtOH. [MoCl_2(salpphen)]_2 was synthesized by reactions of [MoCl_4(CH_3CN)_2] with the …


Voltammetric And Spectroscopic Studies Of Vanadium(V)-- Nicotinamide Interactions At Physiological Ph, Semi̇ha Çakir, Ender Bi̇çer Jan 2007

Voltammetric And Spectroscopic Studies Of Vanadium(V)-- Nicotinamide Interactions At Physiological Ph, Semi̇ha Çakir, Ender Bi̇çer

Turkish Journal of Chemistry

The interaction of nicotinamide (NA) with NH_4VO_3 at the physiological pH (pH 7.4) was studied by voltammetry and UV-Vis spectroscopy. The reduction of V(V) ions complexed with NA in phosphate buffer (pH 7.4) was observed as a well-defined reversible reduction peak at --0.35 V. The stoichiometric (metal:ligand) ratio of the complex of V(V) with NA was determined as 1:2 by the mole ratio method.


Chemoenzymatic Synthesis Of 2-Bromo-6-Hydroxy-3-Methoxy-2-Cyclohexen-1-One, Emi̇ne Özgül Karaaslan, Yasemi̇n Toka Jan 2007

Chemoenzymatic Synthesis Of 2-Bromo-6-Hydroxy-3-Methoxy-2-Cyclohexen-1-One, Emi̇ne Özgül Karaaslan, Yasemi̇n Toka

Turkish Journal of Chemistry

A chemoenzymatic synthesis of 2-bromo-6-hydroxy-3-methoxy-2- cyclohexen-1-one starting from cyclohexane-1,3-dione is reported. Manganese(III) acetate-mediated acetoxylation followed by the enzyme-mediated hydrolysis of \alpha'-acetoxy enone affords hydroxy-enone 5 and acetoxy enone 4 with high enantiomeric excesses in good yields.


A New Approach To Furan-Containing Macrolactones, Christoph Schmidt, Ruth Messmer, Franz Bracher, Jurgen Krauss Jan 2007

A New Approach To Furan-Containing Macrolactones, Christoph Schmidt, Ruth Messmer, Franz Bracher, Jurgen Krauss

Turkish Journal of Chemistry

Furan and tetrahydrofuran heterocycles are part of many natural products, like the Galerucella pheromone, furano epothilones, bipinnatin, and amphidinolides. This paper describes a short and efficient synthetic approach to furan-containing macrolactones in 4 steps, including as key steps a Sonogashira reaction and an olefin metathesis. The resulting compounds were tested at the National Cancer Institute for their cytotoxicity, but did not exhibit significant cytotoxicity in the human tumour cell line screen.


Synthesis Of Some New 1-Acylthiosemicarbazides And 1,2,4-Triazol-5-Thiones, And Their Analgesic And Anti-Inflammatory Activities, Yasemi̇n Dündar, Bi̇lge Çakir, Esra Küpeli̇, M. Fethi̇ Şahi̇n, Ni̇ngur Noyanalpan Jan 2007

Synthesis Of Some New 1-Acylthiosemicarbazides And 1,2,4-Triazol-5-Thiones, And Their Analgesic And Anti-Inflammatory Activities, Yasemi̇n Dündar, Bi̇lge Çakir, Esra Küpeli̇, M. Fethi̇ Şahi̇n, Ni̇ngur Noyanalpan

Turkish Journal of Chemistry

We synthesized new 1-[3-(2-oxobenzothiazolin-3-yl)propanoyl]-4- substituted-thiosemicarbazides and their corresponding cyclized 3-[2-(2-oxobenzothiazoline-3-yl)ethyl]-4-substituted-1,2,4-triazol-5-thione ana-logs in which position 4 of the triazole ring was substituted by cyclohexyl, methyl, allyl, phenyl, p-methylphenyl, p-methoxyphenyl, p-chlorophenyl, p-nitrophenyl, benzyl, and phenylethyl to screen their analgesic and anti-inflammatory activities as well as gastric ulceration potential in test animals. None of the compounds, except 5a, 5e, and 5h, caused gastric lesions or bleeding. Compound 5g was found to have higher analgesic and anti-inflammatory activity among the synthesized compounds.


Synthesis And Antimicrobial Activities Of Some New 1,2,4-Triazole Derivatives, Nurhan Gümrükçüoğlu, Mevlut Serdar, Eli̇f Çeli̇k, Ali̇ Sevi̇m, Nesli̇han Demi̇rbaş Jan 2007

Synthesis And Antimicrobial Activities Of Some New 1,2,4-Triazole Derivatives, Nurhan Gümrükçüoğlu, Mevlut Serdar, Eli̇f Çeli̇k, Ali̇ Sevi̇m, Nesli̇han Demi̇rbaş

Turkish Journal of Chemistry

A series of acylhydrazones (2a-f) were synthesized by the condensation of iminoester hydrochlorides (1a-f) with acyl hydrazines. 2,5-Dialkyl 1,3,4-oxadiazoles (3a,c,e) were obtained in the same reaction media. The treatment of acylhydrazones with hydrazine hydrate afforded 4-amino-3,5-dialkyl-1,2,4-triazoles (4a-c). The acetylation of 4-amino-3,5-dialkyl-1,2,4-triazoles produced N-[3,5-dialkyl-4H-1,2,4-triazol-4-yl] acetamides (5-7). The treatment of compounds 4a and 4c with various aromatic aldehydes resulted in the formation of 4-arylidenamino-3,5-dialkyl-1,2,4-triazoles (8a,d, e, and 10a-e). Sodium borohydride reduction of 4-arylidenamino derivatives afforded 4-alkylamino-3,5-dialkyl-1,2,4-triazoles (9a,d, e, and 11a-e). Compounds 4b, 4c, 7, 8d, and 11c showed good antifungal activity only against yeast-like fungi, while compounds 3e, 6, 8e, and 9e …


Synthesis, Spectroscopic Investigation, Crystal Structure, And Biological Screening, Including Antitumor Activity, Of Organotin(Iv) Derivatives Of Piperonylic Acid, Muhammad Hanif, Mukhtiar Hussain, Saqib Ali, Moazzam H. Bhatti, Muhammad Sheeraz Ahmed, Bushra Mirza, Helen S. Evans Jan 2007

Synthesis, Spectroscopic Investigation, Crystal Structure, And Biological Screening, Including Antitumor Activity, Of Organotin(Iv) Derivatives Of Piperonylic Acid, Muhammad Hanif, Mukhtiar Hussain, Saqib Ali, Moazzam H. Bhatti, Muhammad Sheeraz Ahmed, Bushra Mirza, Helen S. Evans

Turkish Journal of Chemistry

We prepared 8 new organotin compounds with the general formulae [R_3SnL], where R = Me (1), Bu (2), Ph (3), and Cy (4) and [R_2SnL_2], where R = Me (5), Et (6), Bu (7), Oct (8), and L = piperonylic acid, and characterized them by elemental analyses, IR spectra, and multinuclear NMR (^1H, ^{13}C, and ^{119}Sn). The structure of 5 was confirmed by single crystal X-ray crystallography. The geometry around the tin atom was compared in both solution and solid state. Crystals of 5 are monoclinic with the space group P2_1/c. The tin geometry is skew trapezoidal bipyramidal, with 2 …


Synthesis Of Some Novel 3,5-Diaryl-1,2,4-Triazole Derivatives And Investigation Of Their Antimicrobial Activities, Mevlut Serdar, Nurhan Gümrükçüoğlu, Şengül Alpay Karaoğlu, Nesli̇han Demi̇rbaş Jan 2007

Synthesis Of Some Novel 3,5-Diaryl-1,2,4-Triazole Derivatives And Investigation Of Their Antimicrobial Activities, Mevlut Serdar, Nurhan Gümrükçüoğlu, Şengül Alpay Karaoğlu, Nesli̇han Demi̇rbaş

Turkish Journal of Chemistry

A series of acylhydrazones (2a-d) was synthesized from the reactions of iminoester hydrochlorides (1a-e) with acyl hydrazines. 2,5-Dialkyl 1,3,4-oxadiazoles (3a-d) were obtained in the same reaction media. The treatment of acylhydrazones with hydrazine hydrate afforded 4-amino-3,5-dialkyl-1,2,4-triazoles (4a-c). The acetylation of 4-amino-3-(4-hydroxyphenyl)-5-phenyl-4H-1,2,4-triazole (4a) produced 4-amino-5-(4-acetoxyphenyl)-3-phenyl-4H-1,2,4-triazole (9), while the acetylation of 4-amino-3-(4-tolyl)-5-phenyl-4H-1,2,4-triazole (4b) gave 4-acetylamino-3-phenyl-5-(4-tolyl)-4H-1,2,4-triazole (10). The treatment of compound 4b with various aromatic aldehydes or acetophenone and 4-nitroacetophenone resulted in the formation of 4-arylidenamino-3,5-dialkyl-4H-1,2,4-triazoles (5a-e and 7a,b). Sodium borohydride reduction of 4-arylidenamino derivatives of 1,2,4-triazoles afforded 4-alkylamino-3,5-dialkyl-4H-1,2,4-triazoles (6a-e and 8a,b). All newly synthesized compounds were screened for their antimicrobial and antifungal …


New Diterpenoids From The Aerial Parts Of Salvia Pilifera, Ufuk Kolak Jan 2007

New Diterpenoids From The Aerial Parts Of Salvia Pilifera, Ufuk Kolak

Turkish Journal of Chemistry

Three new diterpenoids, piliferol (2\alpha, 20-dihydroxy-12-oxo- abieta-9(11),13-dien-8,20-ether) (1), salvipiliferol (2\alpha, 10\beta -dihydroxy-12-oxo-norabieta-9(11),13-dien) (2), and piliferalactone (2\alpha ,8-dihydroxy-12-oxo-abieta-9(11),13-dien-20-oic acid-8,20-lactone) (3), together with 7 known compounds, ursolic acid, oleanolic acid, betulinic acid, \alpha -amyrin, lupeol, \beta -sitosterol, and pectolinarigenin, have been isolated from the aerial parts of an endemic Salvia species, S. pilifera. Their structures were elucidated by spectral (UV, IR, 1D-, and 2D-NMR, and HRMS) methods.


Constituents Of Nepeta Crassifolia (Lamiaceae), Syed Amir Ibrahim, Muhammad Shaiq Ali Jan 2007

Constituents Of Nepeta Crassifolia (Lamiaceae), Syed Amir Ibrahim, Muhammad Shaiq Ali

Turkish Journal of Chemistry

A long chain ketone (crassifone), a pentacyclic triterpenoid coupled with fatty acid moiety (crassifoate), and an acyclic diterpenoid (crassifol) have been isolated from the ethanol soluble part of Nepeta crassifolia (Lamiaceae) collected from Kangavar, Iran. Structures of all the metabolites were elucidated with the aid of spectroscopic techniques, including 2D NMR experiments.


Preparation, Spectroscopy, Antimicrobial Assay, And X-Ray Structure Of Dimethyl Bis-(4-Methylpiperidine Dithiocarbamato-S,S`)-Tin(Iv), Zia-Ur Rehman, Saira Shahzadi, Saqib Ali, Guo-Xin Jin Jan 2007

Preparation, Spectroscopy, Antimicrobial Assay, And X-Ray Structure Of Dimethyl Bis-(4-Methylpiperidine Dithiocarbamato-S,S`)-Tin(Iv), Zia-Ur Rehman, Saira Shahzadi, Saqib Ali, Guo-Xin Jin

Turkish Journal of Chemistry

Dimethyl bis(4-methylpiperidine dithiocarbamato-S,S')-tin(IV) was synthesized and characterized by elemental analysis, IR and mass spectrometry, multinuclear NMR (^1H- and ^{13}C-NMR), and X-ray single crystal analysis. IR data showed that the ligand acts as a bidentate in the solid state. X-ray data showed the unsymmetrical nature of the ligand towards coordination to tin. It crystallized in the monoclinic P2_1/n space group. Its geometry is distorted octahedral. Antimicrobial activity data shows that the complex exhibits significantly more activity than the free ligand.


Opto-Electrical Properties Of Copper-Indium-Selenium Thin Films, S. F. Shaukat, S. A. Khan, Robina Farooq Jan 2007

Opto-Electrical Properties Of Copper-Indium-Selenium Thin Films, S. F. Shaukat, S. A. Khan, Robina Farooq

Turkish Journal of Physics

Copper-Indium-Selenium (CIS) thin films have been characterised using various experimental techniques. These compounds are extensively used in solar cell technology as absorber layers due to their exciting characteristics. Optical transmission measurements on different compositions of CIS films are observed and the absorption coefficient is determined. The Van der Pauw technique is used to divulge the electrical characteristics of these films. The electrical conductivity is found relatively high for the films annealed in vacuum but decreases for films synthesised optimally. It is observed that p-type films have higher conductivity than n-type films. The grain size, composition, structure and the spacing of …