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Full-Text Articles in Physical Sciences and Mathematics

Synthesis And Phase Transition Studies Of New Dimer Compounds Connected To A 1,3-Dimethylbarbituric Acid Core, Abdulkarim-Talaq Mohammad, Guan-Yeow Yeap, Hasnah Osman Jan 2014

Synthesis And Phase Transition Studies Of New Dimer Compounds Connected To A 1,3-Dimethylbarbituric Acid Core, Abdulkarim-Talaq Mohammad, Guan-Yeow Yeap, Hasnah Osman

Turkish Journal of Chemistry

A series of dimeric unsymmetrical liquid crystals derived from heterocyclic 1,3-dimethylbarbituric acid exhibiting smectic A and nematic phase are reported. All compounds were prepared by the condensation of 4'-(R-(4-formylphenoxy)butoxy)biphenyl-4-carboxylate with 1,3-dimethylbarbituric acid in ethanol. The mesomorphic properties were investigated by DSC and POM, where the type of phase depends on the length of spacer alkoxy chains and the length of the terminal chain. While the SmA phase was observed upon the heating and cooling run when the spacer alkoxy chains carbon numbers increased (n = 6), the N phase was observed when the length of spacer alkoxy chains increased (n …


Investigation Of The Adsorption Kinetics Of Methylene Blue Onto Cotton Wastes, Bi̇lal Acemi̇oğlu, Murat Ertaş, Mehmet Hakki Alma, Mustafa Usta Jan 2014

Investigation Of The Adsorption Kinetics Of Methylene Blue Onto Cotton Wastes, Bi̇lal Acemi̇oğlu, Murat Ertaş, Mehmet Hakki Alma, Mustafa Usta

Turkish Journal of Chemistry

Cotton stalk (CS), cotton waste (CW), and cotton dust (CD), which are cotton wastes, were used as adsorbents to study the adsorption kinetics of methylene blue from aqueous solution. Kinetics of the batch adsorption experiment was investigated according to the pseudo-first order, the pseudo-second order, and the intraparticle diffusion models used commonly in the literature. The effects of the initial concentration, solution pH, and temperature on kinetic parameters (adsorption rate constant, initial adsorption rate, equilibrium adsorption capacity, etc.) were studied. The results showed that the adsorption process was well fitted to the pseudo-second order model for all adsorbents. The activation …


Facile Synthesis Of 5-Bromotropono[C]-Fused Pyrazoles And Isoxazole, Yang Li, Liangyu Xu, Wentao Gao Jan 2014

Facile Synthesis Of 5-Bromotropono[C]-Fused Pyrazoles And Isoxazole, Yang Li, Liangyu Xu, Wentao Gao

Turkish Journal of Chemistry

A facile synthesis of a series of new 5-bromotropono[c]pyrazole derivatives (3 and 10--15) as well as 5-bromotropono[c]isoxazole (17) is described, involving a condensation reaction of 3-acetyl-5-bromotropolone (1) with hydrazine monohydrate (2), arylhydrazine hydrochlorides (4--9), and hydroxylamine hydrochloride (16), respectively. All the synthesized compounds were obtained in good yields of 56%--77% and their structures were characterized by spectral data and HRMS.


Spectroscopic Investigation And Oxidation Of The Anticholinergic Drug Atropine Sulfate Monohydrate By Hexacyanoferrate(Iii) In Aqueous Alkaline Media: A Mechanistic Approach, Manjunath Meti, Sharanappa Nandibewoor, Shivamurti Chimatadar Jan 2014

Spectroscopic Investigation And Oxidation Of The Anticholinergic Drug Atropine Sulfate Monohydrate By Hexacyanoferrate(Iii) In Aqueous Alkaline Media: A Mechanistic Approach, Manjunath Meti, Sharanappa Nandibewoor, Shivamurti Chimatadar

Turkish Journal of Chemistry

The oxidation of the anticholinergic drug atropine sulfate monohydrate by hexacyanoferrate(III) in aqueous alkaline media was investigated spectrophotometrically by monitoring the decrease in absorbance of hexacyanoferrate(III) (HCF(III)). Oxidation products were identified. The oxidation mechanism was proposed from kinetic studies. The reaction constants involved in the different steps of the mechanism were calculated. The effects of added products, ionic strength, and dielectric constant of the reaction were investigated. The polymerization test revealed that oxidation occurred with intervention of free radicals. The activation parameters were evaluated.


Selective Oxidation Of Sulfides And Hydrocarbons With H_2o_2 Over Manganese Catalyst Supported On Nanoparticles, Massomeh Ghorbanloo, Roghayeh Tarasi, Jun Tao, Hidenori Yahiro Jan 2014

Selective Oxidation Of Sulfides And Hydrocarbons With H_2o_2 Over Manganese Catalyst Supported On Nanoparticles, Massomeh Ghorbanloo, Roghayeh Tarasi, Jun Tao, Hidenori Yahiro

Turkish Journal of Chemistry

A new magnetically separable catalyst consisting of binuclear Mn(II) complex [Mn_2(HL)_2(H_2O)_4], HL = 2-[(2-hydroxy-benzylidene)-amino]-3-(4-hydroxyphenyl)-propionic acid, supported on (3-chloropropyl)-trimethoxysilane (CPTMS) functionalized silica-coated magnetic nanoparticles (MNPs) was prepared. The synthesized catalyst was characterized by several physico-chemical and spectroscopic methods. This immobilized complex was found to be an efficient heterogeneous catalyst for the oxidation of different sulfides and hydrocarbons using hydrogen peroxide (H_2O_2) as an oxidant. The catalyst is readily recovered by simple magnetic decantation and can be recycled several times with no considerable loss of catalytic activity.


Solvent Extraction Of Praseodymium(Iii) From Acidic Nitrate Medium Using Cyanex 921 And Cyanex 923 As Extractants In Kerosene, Nandita Panda, Nihar Bala Devi, Sujata Mishra Jan 2014

Solvent Extraction Of Praseodymium(Iii) From Acidic Nitrate Medium Using Cyanex 921 And Cyanex 923 As Extractants In Kerosene, Nandita Panda, Nihar Bala Devi, Sujata Mishra

Turkish Journal of Chemistry

Solvent extraction of praseodymium(III) from acidic nitrate medium by the neutral organophosphorous extractants Cyanex 921 and Cyanex 923 in kerosene was studied. The effects of various parameters like equilibration time, nitric acid concentration, nitrate ion concentration, extractant concentration, temperature, and nature of diluents on the extraction behavior of Pr(III) were investigated. The extraction of 0.001 M Pr(III) was quantitative (93%) from the aqueous phase containing 0.001 M HNO_3 and 0.1 M KNO_3 using 0.5 M Cyanex 921/1 M Cyanex 923. On the basis of slope analysis, the compositions of the extracted species were formulated as Pr(NO_3)_3.2Cyanex 921 and Pr (NO_3)_3.Cyanex …


In Vitro Effects Of Pesticide Exposure On The Activity Of The Paraoxonase-1 Enzyme From Sheep Liver Microsomes, Büşra Cebeci̇, Zuhal Alim, Şükrü Beydemi̇r Jan 2014

In Vitro Effects Of Pesticide Exposure On The Activity Of The Paraoxonase-1 Enzyme From Sheep Liver Microsomes, Büşra Cebeci̇, Zuhal Alim, Şükrü Beydemi̇r

Turkish Journal of Chemistry

The organophosphate target enzyme paraoxonase-1 (PON1) has been extensively studied in toxicology. Pesticides are organophosphate compounds that are commonly used in agriculture. They are also used as nerve gases, such as sarin and soman. Therefore, the effects of these compounds on enzymatic activity are well known. In the present study, we investigated the in vitro effects of fenoxaprop-p-ethyl, lambda cyhalothrin, imidacloprid, and dichlorvos pesticides on sheep liver microsomal PON1. The enzyme was purified approximately 141-fold with a specific activity of 1822.22 EU/mg proteins. The pesticides inhibited sheep liver PON1 in vitro, and the IC_{50} values for these compounds were 0.0103, …


Application Of 3-Aroyl-4(5)-Arylimidazols As Efficient Ligands In Pd-Catalyzed Heck Reactions, Mojtaba Amini, Seyedeh Motahhareh Amini, Bagher Eftekhari-Sis, Ali Keivanloo Jan 2014

Application Of 3-Aroyl-4(5)-Arylimidazols As Efficient Ligands In Pd-Catalyzed Heck Reactions, Mojtaba Amini, Seyedeh Motahhareh Amini, Bagher Eftekhari-Sis, Ali Keivanloo

Turkish Journal of Chemistry

The Heck coupling of haloarenes with various alkenes was successfully performed in the presence of 0.25 mol % PdCl_2 and 0.5 mol % biphenyl-4-yl-[4(5)-(biphenyl-4-yl)-1H-imidazol-2-yl]ketone 2f as a ligand with Na_2CO_3 as optimal base, in a 1:1 mixture of H_2O/DMF as the reaction solvent at 80 ^°C for 8 h. Imidazole 2f was found to be an inexpensive, air-stable, easily available, and efficient ligand in the palladium-catalyzed Heck reactions of aryl iodides (76 %--94 %), bromides (52 %--79 %), and chlorides (40 %--70 %).


Synthesis Of Novel Imidazo[1,2-A]Pyridines And Evaluation Of Their Antifungal Activities, Füsun Göktaş, Nesri̇n Cesur, Di̇lek Şatana, Meltem Uzun Jan 2014

Synthesis Of Novel Imidazo[1,2-A]Pyridines And Evaluation Of Their Antifungal Activities, Füsun Göktaş, Nesri̇n Cesur, Di̇lek Şatana, Meltem Uzun

Turkish Journal of Chemistry

New 2-(imidazo[1,2-a]pyridin-2-ylcarbonyl)-N-substituted hydrazinecarbothioamides (4a--j), N'-(3-substituted-4-oxo-1,3-thiazolidin-2-ylidene)imidazo[1,2-a]pyridine-2-carbohydrazides (5a--f), and N-(nonsubstituted/4-substituted phenyl)-5-(imidazo[1,2-a]pyridine-2-yl)-1,3,4-oxadiazole-2-amines (6a--d) were synthesized from imidazo[1,2-a]pyridine-2-carbohydrazide (3) and evaluated for antifungal activity against Microsporum gypseum NCPF 580, M. canis, Trichophyton tonsurans NCPF 245, T. rubrum, Candida albicans ATCC 10231, and C. parapsilosis ATCC 22019 using amphotericin B as the standard. The chemical structures of the compounds were confirmed by elemental analysis, IR, ^1H NMR, ^{13}C NMR, HMBC (^{13}C, ^1H), and mass spectra. Most of the tested compounds showed moderate antifungal activity. Hydrazinecarbothioamide derivatives 4h and 4f exhibited the highest activity against M. canis (MIC: 2 \mu g mL^{-1} and 4 \mu g …


Selective Co Methanation Over Ceo_2--Zro_2-Composed Nio And Co_3o_4 Catalysts, Fi̇li̇z Derekaya, Derya Ermergen Jan 2014

Selective Co Methanation Over Ceo_2--Zro_2-Composed Nio And Co_3o_4 Catalysts, Fi̇li̇z Derekaya, Derya Ermergen

Turkish Journal of Chemistry

CeO_2--ZrO_2-composed NiO and Co_3O_4 catalysts were prepared by 3 different methods. Both CO methanation and selective CO methanation were carried out. All catalysts were prepared by (1) co-precipitation, (2) surfactant-assisted co-precipitation, and (3) surfactant-assisted co-precipitation with ultrasound mixing methods. Catalysts were characterized by using N_2 physisorption, XRD, SEM, TEM, and TPR-H_2 techniques. The highest surface area value, uniform pore size distribution, and pores having small diameters were observed for the catalysts prepared by using the surfactant and ultrasound. The NiO/CeO_2/ZrO_2 prepared by the surfactant-assisted co-precipitation was the most active catalyst for CO methanation. It gave 50 % CO conversion to …


Catalytic Conversion Of Carbon Dioxide Into Cyclic Carbonates By Cu(Ii) And Ni(Ii) Acetylacetonates Anchored Onto Siral 80, Senem Coşkun, Zeynep Taşci, Mahmut Ulusoy, Mürüvvet Yurdakoç Jan 2014

Catalytic Conversion Of Carbon Dioxide Into Cyclic Carbonates By Cu(Ii) And Ni(Ii) Acetylacetonates Anchored Onto Siral 80, Senem Coşkun, Zeynep Taşci, Mahmut Ulusoy, Mürüvvet Yurdakoç

Turkish Journal of Chemistry

Ni and Cu acetylacetonates were anchored onto Siral 80 and used in the catalytic conversion of carbon dioxide. The catalysts were characterized by several methods such as XRD, FTIR, SEM, and TGA/DTG. The catalytic domains of the prepared heterogeneous complexes and their homogeneous counterparts were examined for the conversion reaction of carbon dioxide into cyclic carbonates in the presence of different additives (1.5 MPa CO_2 pressure, 100 ^°C, and 2 h). Good to excellent conversions were observed using Siral 80/APTES/Cu(acac)_2 catalysts and butylmethylimidazolium hexafluorophosphate, [bmim]PF_6, ionic liquid from the reaction of CO_2, and different epoxides. Modification with APTES made the …


Poly(Vinyl Chloride) Functionalization By Aliphatic And Aromatic Amines: Application To The Extraction Of Some Metal Cations, Fayçel Ammari, Faouzi Meganem Jan 2014

Poly(Vinyl Chloride) Functionalization By Aliphatic And Aromatic Amines: Application To The Extraction Of Some Metal Cations, Fayçel Ammari, Faouzi Meganem

Turkish Journal of Chemistry

The aim of this study was to evaluate the efficiency of 3 new polymers obtained by functionalization of a commercial poly(vinyl chloride) by grafting amino-alkyl and amino-aryl groups to extract some metal cations from aqueous solutions. The percentage of extraction was determined by comparing the initial electrical conductivity of the aqueous solution containing the studied metal and that of the aqueous solution at the extraction equilibrium. One of the obtained polymers gave an extraction ratio of Sn^{2+} = 87.1 %, which highlight the importance of the substitution of chlorine atoms by diethylenetriamine groups. These results were compared with those obtained …


Convenient Synthesis Of New Polysubstituted Isoindole-1,3-Dione Analogues, Ayşe Tan, Mustafa Zahri̇tti̇n Kazancioğlu, Derya Aktaş, Özlem Gündoğdu, Ertan Şahi̇n, Nurhan Ki̇shali, Yunus Kara Jan 2014

Convenient Synthesis Of New Polysubstituted Isoindole-1,3-Dione Analogues, Ayşe Tan, Mustafa Zahri̇tti̇n Kazancioğlu, Derya Aktaş, Özlem Gündoğdu, Ertan Şahi̇n, Nurhan Ki̇shali, Yunus Kara

Turkish Journal of Chemistry

Three new polysubstituted isoindole-1,3-diones were prepared from 2-ethyl-5-hydroxy-3a,4,5,7a-tetrahydro-isoindole-1,3-dione. The reaction of 2-ethyl-5-hydroxy-3a,4,5,7a-tetrahydro-isoindole-1,3-dione with m-CPBA gave the corresponding epoxide. The triacetate derivative was obtained via cis-hydroxylation using OsO_4, followed by acetylation. An aromatic derivative, a secondary reaction product, was also formed during the acetylation. Finally, a tricyclic derivative from 2-ethyl-5-hydroxy-3a,4,5,7a-tetrahydro-isoindole-1,3-dione was synthesized via dichloroketene addition under microwave irradiation. The exact structures of epoxide and tricyclic derivatives were determined by X-ray diffraction analysis.


Aqueous Dabco, An Efficient Medium For Rapid Organocatalyzed Knoevenagel Condensation And The Gewald Reaction, Mohammad Saeed Abaee, Somayeh Cheraghi Jan 2014

Aqueous Dabco, An Efficient Medium For Rapid Organocatalyzed Knoevenagel Condensation And The Gewald Reaction, Mohammad Saeed Abaee, Somayeh Cheraghi

Turkish Journal of Chemistry

In the presence of water and 1,4-diazabicyclo[2.2.2]octane, several aldehydes and cyclic ketones underwent efficient Knoevenagel condensation with malononitrile and ethyl cyanoacetate to produce the respective \alpha.\beta-unsaturated systems within fairly short time periods. As a result, high yields of conjugated products were easily obtained. Products could be engaged in a Gewald reaction, either stepwise or in situ, to produce efficiently their respective 2-aminothiophenes within 4--7 h.


Thermal Conversion Of Glycerol To Value-Added Chemicals: Pyridine Derivatives By One-Pot Microwave-Assisted Synthesis, Duygu Bayramoğlu, Gökay Gürel, Ali̇ Sinağ, Mustafa Güllü Jan 2014

Thermal Conversion Of Glycerol To Value-Added Chemicals: Pyridine Derivatives By One-Pot Microwave-Assisted Synthesis, Duygu Bayramoğlu, Gökay Gürel, Ali̇ Sinağ, Mustafa Güllü

Turkish Journal of Chemistry

One-pot syntheses of the value-added heterocyclic compounds 3-methylpyridine and pyridine using a renewable chemical, glycerol, were achieved in acidic medium by thermal conversion reactions. Condensation/cyclization reactions of the thermal degradation products of glycerol were investigated in situ using different ammonia and acidic moiety producing inorganic ammonium salts under pyrolysis or microwave heating conditions. The reaction parameters were studied in detail and satisfying product yields up to 72 % were obtained under optimized conditions. Structural identification of all compounds was accomplished by spectroscopic methods.


Synthesis And Characterization Of A Novel 3-Amino-1,2,4-Triazole Lead(Ii) Coordination Polymer, Şebnem Esen Sözerli̇, Arzu Özen, İbrahi̇m Kani̇, Deni̇z Demi̇r Jan 2014

Synthesis And Characterization Of A Novel 3-Amino-1,2,4-Triazole Lead(Ii) Coordination Polymer, Şebnem Esen Sözerli̇, Arzu Özen, İbrahi̇m Kani̇, Deni̇z Demi̇r

Turkish Journal of Chemistry

A novel [Pb_2(\mu-atrz)_2(\mu-CH_3COO)(CH_3COO)]_n (atrz = 3-amino-1,2,4-triazole) complex was synthesized and characterized by IR spectroscopy, thermogravimetric analysis, and single crystal X-ray diffraction. The molecular structure shows that the complex is a coordination polymer in which there are 2 different lead(II) ions with coordination number of 5, Pb(2), and, with a coordination number of 4, Pb(1). Each atrz acts as a bridging ligand between 2 Pb(II) ions through the 2 adjacent nitrogen atoms of the triazole ring. The acetate anions show different types of coordination mode: one acts as a bridge by coordination of the same oxygen atom with Pb(II) ions and …


Linear Assembly And 3d Networks Of Peptide Modified Gold Nanoparticles, Şaban Kalay, Clement Blanchet, Mustafa Çulha Jan 2014

Linear Assembly And 3d Networks Of Peptide Modified Gold Nanoparticles, Şaban Kalay, Clement Blanchet, Mustafa Çulha

Turkish Journal of Chemistry

The charge and size of molecules chemically attached to nanoparticles (NPs) play an important role in their interaction behavior in suspensions. Gold nanoparticles (AuNPs) were modified systematically with peptides and the modification was verified with surface-enhanced Raman scattering (SERS). The behavior of the modified AuNPs in suspension and at the liquid--solid interface was monitored using small angle X-ray scattering (SAXS), UV/Vis spectroscopy and dynamic light scattering (DLS) in suspension, and atomic force microscopy (AFM) at the solid--liquid interface. It was found that while negatively charged peptide modified AuNPs behave very similar to citrate reduced AuNPs due to their negatively charged …


Effects Of Functional Groups Of Triple Bonds Containing Molecules On Nickel Electroplating, Esma Sezer, Belkiz Ustamehmetoğlu, Ramazan Katirci Jan 2014

Effects Of Functional Groups Of Triple Bonds Containing Molecules On Nickel Electroplating, Esma Sezer, Belkiz Ustamehmetoğlu, Ramazan Katirci

Turkish Journal of Chemistry

The effects of propargyl alcohol (PA), propynol ethoxylate (PME), propargyl sulfonate (PS), and diethylaminopropyne (DEP) compounds as additives in a Watts bath on coating brightness, thickness, and efficiency were investigated and compared using electrochemical methods such as linear and square wave voltammetry (SWV), chronoamperometry, chronopotentiometry, electrochemical impedance (EIS), and X-ray fluorescence (XRF) spectroscopy. The charge transfer resistance values obtained in the presence of PA and PME were similar and higher than the other values obtained; this result suggests that PA and PME have better adsorption. The optic and XRF measurements revealed that for the PS molecule the plating is the …


Qsar Study Of Chalcone Derivatives As Anti-Leishmania Agents, Maryam Iman, Asghar Davood, Nasim Banarouei Jan 2014

Qsar Study Of Chalcone Derivatives As Anti-Leishmania Agents, Maryam Iman, Asghar Davood, Nasim Banarouei

Turkish Journal of Chemistry

Quantitative structure activity relationship analyses were used to identify the ideal physicochemical characteristics of potential chalcone derivatives as anti-Leishmania agents. The HyperChem program was used to build chalcone structures and to perform conformational analyses through the semiempirical method followed by the PM3 force field. Dragon calculated a large number of molecular descriptors. Multilinear regression was used for quantitative structure activity relationship modeling. Based on our computational studies, 4 descriptors, SEigv, RDF125v, RDF055u, and O-058, can affect the activity of chalcone derivatives.


Binding Of Flavanone With \Beta-Cd/Ctdna: A Spectroscopic Investigation, Chandrasekaran Sowrirajan, Sameena Yousuf, Muthu Vijayan Enoch Israel Vijayaraj Jan 2014

Binding Of Flavanone With \Beta-Cd/Ctdna: A Spectroscopic Investigation, Chandrasekaran Sowrirajan, Sameena Yousuf, Muthu Vijayan Enoch Israel Vijayaraj

Turkish Journal of Chemistry

The inclusion complexation of flavanone with \beta-cyclodextrin was studied by ultraviolet absorption, steady state fluorescence, time-resolved fluorescence, and 2D ROESY nuclear magnetic resonance spectroscopic techniques. A 1:1 stoichiometric ratio was determined for the inclusion of flavanone with \beta-cyclodextrin. The Stern--Volmer constant for the accessible fraction of the binding of flavanone with \beta-cyclodextrin, and the binding constant for the flavanone--\beta-cyclodextrin complex are reported. The flavanone--\beta-cyclodextrin inclusion complex was characterized by 2D ROESY NMR spectroscopy. The binding of flavanone with ctDNA and the effect of \beta-cyclodextrin on the binding of flavanone to ctDNA were studied by absorption and fluorescence techniques. Binding constants …


Simultaneous Determination Of Dexpanthenol, Lidocaine Hydrochloride, And Mepyramine Maleate In Combined Pharmaceutical Gel By Capillary Electrophoresis, Gülden Akyil, Hayri̇ye Eda Şatana Kara, Sezen Yarimkaya Baş, Nusret Ertaş, Ni̇lgün Günden Göğer Jan 2014

Simultaneous Determination Of Dexpanthenol, Lidocaine Hydrochloride, And Mepyramine Maleate In Combined Pharmaceutical Gel By Capillary Electrophoresis, Gülden Akyil, Hayri̇ye Eda Şatana Kara, Sezen Yarimkaya Baş, Nusret Ertaş, Ni̇lgün Günden Göğer

Turkish Journal of Chemistry

A new capillary electrophoresis method was developed for the simultaneous determination of dexpanthenol (DEX), lidocaine (LID), and mepyramine (MEP) in pharmaceutical preparations. The best results were obtained using 20 mM (pH 3.0) phosphate buffer as the background electrolyte. Separation was obtained using a fused-silica capillary (75 \mu m internal diameter, 50 cm total length, 41 cm effective length) and a potential of +30 kV at 20 °C. Standards and samples were injected using a pressure injection at 50 mbar for 5 s and the analytes were monitored at a detection wavelength of 200 nm. Under optimum conditions, migration times were …


Ultrarapid Catalytic Reduction Of Some Dyes By Reusable Novel Erythromycin-Derived Silver Nanoparticles, Yasmeen Junejo, Abdulhadi̇ Baykal Jan 2014

Ultrarapid Catalytic Reduction Of Some Dyes By Reusable Novel Erythromycin-Derived Silver Nanoparticles, Yasmeen Junejo, Abdulhadi̇ Baykal

Turkish Journal of Chemistry

A novel green approach for the synthesis of silver nanoparticles using erythromycin as a reducing/capping agent is presented. Erythromycin-derived silver nanoparticles were characterized by ultraviolet-visible spectroscopy, scanning electron microscopy, high resolution transmission electron microscopy, X-ray powder diffraction, and Fourier transform infrared spectroscopy. Monodispersed silver nanoparticles showed excellent and promising catalytic activity for reduction of 3 differently charged dyes (eosin B, methylene blue, and rose bengal) in the presence of NaBH_4. The study revealed that 100% reduction of these dyes can be achieved efficiently in just 150--250 s. They were easily recovered from the reaction medium and were reused 5 times, …


Study On Transportation Of Phenol Through A Nanotubule Membrane, Yue Liu, Li Xie, Xiaoxue Fan, Dingyan Fan, Shasheng Huang Jan 2014

Study On Transportation Of Phenol Through A Nanotubule Membrane, Yue Liu, Li Xie, Xiaoxue Fan, Dingyan Fan, Shasheng Huang

Turkish Journal of Chemistry

Gold nanochannels were prepared by plating electrolessly gold within the pores of polycarbonate filter membranes (PCTMs). These PCTMs with cylindrical Au nanotubules of uniform radius and high density can be used as a convenient model system to investigate the mechanism of particle transport through nanotubules. The transport properties of phenol through a modified Au nanotubule membrane were studied. The permeate flux of phenol transport through the nanotubule membrane can be spatially and temporally manipulated by controlling the magnitude and direction of the current applied across the separation cell, and the electroosmotic flow (EOF) was investigated by measuring the flux of …


Synthesis, Anticandidal Activity, And Cytotoxicity Of Some Thiazole Derivatives With Dithiocarbamate Side Chains, Leyla Yurttaş, Yusuf Özkay, Fati̇h Demi̇rci̇, Gamze Göger, Şafak Ulusoylar Yildirim, Usama Abu Mohsen, Ömer Öztürk, Zafer Asim Kaplancikli Jan 2014

Synthesis, Anticandidal Activity, And Cytotoxicity Of Some Thiazole Derivatives With Dithiocarbamate Side Chains, Leyla Yurttaş, Yusuf Özkay, Fati̇h Demi̇rci̇, Gamze Göger, Şafak Ulusoylar Yildirim, Usama Abu Mohsen, Ömer Öztürk, Zafer Asim Kaplancikli

Turkish Journal of Chemistry

Some thiazole derivatives bearing dithiocarbamic acid esters were synthesized in order to investigate their anticandidal activity and cytotoxicity. The structures of the obtained final compounds (6a--j) were confirmed by spectral data (IR, ^1H NMR, ^{13}C NMR, and MS) and elemental analysis. The anticandidal activity of the compounds was determined (6a--j) using the microbroth dilution method and their cytotoxicity was evaluated according to the MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay against normal cells. Contrary to expectations, weak antifungal activity was observed with IC_{50} values ranging between 30 and 403 \mu g/mL.


Synthesis And Characterization Of Magnesium Borate Minerals Of Admontite And Mcallisterite Obtained Via Ultrasonic Mixing Of Magnesium Oxide And Various Sources Of Boron: A Novel Method, Azmi̇ Seyhun Kipçak, Emek Moroydor Derun, Sabri̇ye Pi̇şki̇n Jan 2014

Synthesis And Characterization Of Magnesium Borate Minerals Of Admontite And Mcallisterite Obtained Via Ultrasonic Mixing Of Magnesium Oxide And Various Sources Of Boron: A Novel Method, Azmi̇ Seyhun Kipçak, Emek Moroydor Derun, Sabri̇ye Pi̇şki̇n

Turkish Journal of Chemistry

Magnesium borates can be used as detergent compounds or hydrocarbon catalyzers and in the ceramics industry for superconductor material manufacture owing to their high elastic coefficient and resistance to corrosion at high temperatures. In the present study, the synthesis of magnesium borate was facilitated via a novel ultrasonic method of mixing and the identification and characterization of the material were carried out via X-Ray diffraction (XRD), Fourier transform infrared (FT-IR), and Raman spectroscopies, and the B_2O_3 content was determined through titration. The surface morphology was investigated using scanning electron microscopy (SEM). The results of the XRD analysis identified the synthesized …


Green Synthesis Of Fe_3o_4 Nanoparticles By One-Pot Saccharide-Assisted Hydrothermal Method, Ayşe Demi̇r, Abdulhadi̇ Baykal, Hüseyi̇n Sözeri̇ Jan 2014

Green Synthesis Of Fe_3o_4 Nanoparticles By One-Pot Saccharide-Assisted Hydrothermal Method, Ayşe Demi̇r, Abdulhadi̇ Baykal, Hüseyi̇n Sözeri̇

Turkish Journal of Chemistry

A saccharide-assisted hydrothermal route starting from a single iron precursor was employed to study the influence of reducing saccharides on the formation of iron oxide (Fe_3O_4) nanoparticles (NPs). Fe_3O_4 NPs, which were confirmed by X-ray diffraction analysis, were successfully synthesized by a hydrothermal method in which mannose, maltose, lactose, and galactose served as reducing agents. The formation of Fe_3O_4 NPs was also confirmed by Fourier transform infrared spectroscopy. Samples exhibited different crystallite sizes estimated based on line profile fitting as 12 \pm 2, 9 \pm 2, 13 \pm 3, and 9 \pm 3 nm for mannose, maltose, lactose, and galactose, …


Graphene Oxide--Magnetite Nanocomposite As An Efficient And Magnetically Separable Adsorbent For Methylene Blue Removal From Aqueous Solution, Kadem Meral, Önder Meti̇n Jan 2014

Graphene Oxide--Magnetite Nanocomposite As An Efficient And Magnetically Separable Adsorbent For Methylene Blue Removal From Aqueous Solution, Kadem Meral, Önder Meti̇n

Turkish Journal of Chemistry

We report a facile method to produce a magnetically separable graphene oxide--magnetite nanocomposite (GO--Fe_3O_4) and its adsorption performance in methylene blue (MB) removal from aqueous solution. The GO--Fe_3O_4 nanocomposite was synthesized by a solution-phase self-assembly method including the incorporation of monodisperse Fe_3O_4 nanoparticles (NPs) and GO in a dimethylformamide/chloroform mixture under sonication. The successfully decorating GO sheet with monodisperse Fe_3O_4 NPs was proved by TEM study. ICP--OES data of the GO--Fe_3O_4 nanocomposite show that the GO--Fe_3O_4 nanocomposite consists of 21 wt% Fe_3O_4 NPs, which is sufficient for its magnetic separation from aqueous solution. The spectroscopic studies reveal that the GO--Fe_3O_4 …


Calixcephems: Clustered Cephalosporins Analogous To Calixpenams As Novel Potential Anti-Mrsa Agents, Fazel Nasuhi Pur, Karim Akbari Dilmaghani Jan 2014

Calixcephems: Clustered Cephalosporins Analogous To Calixpenams As Novel Potential Anti-Mrsa Agents, Fazel Nasuhi Pur, Karim Akbari Dilmaghani

Turkish Journal of Chemistry

Two novel clusters of cephalosporin based on calixarene were synthesized directly or by ring expansion of the penicillin arms of calixpenams to the corresponding cephem arms via sulfoxide intermediates. Antibiotic tests showed that calixcephems have a noteworthy increase in antibacterial activity against methicillin-resistant strains of Staphylococcus aureus (MRSA) with respect to parent calixpenams and their corresponding single cephems.


Graphite Oxide As An Efficient Solid Reagent For Esterification Reactions, Maryam Mirzaaghayan, Rabah Boukherroub, Mahshid Rahimifard Jan 2014

Graphite Oxide As An Efficient Solid Reagent For Esterification Reactions, Maryam Mirzaaghayan, Rabah Boukherroub, Mahshid Rahimifard

Turkish Journal of Chemistry

Esterification of organic acids with alcohols under mild conditions in high yields using graphite oxide, a readily available and inexpensive material, as an effective reagent is described.


Rosmarinic Acid: A Potent Carbonic Anhydrase Isoenzymes Inhibitor, Meryem Topal, İlhami̇ Gülçi̇n Jan 2014

Rosmarinic Acid: A Potent Carbonic Anhydrase Isoenzymes Inhibitor, Meryem Topal, İlhami̇ Gülçi̇n

Turkish Journal of Chemistry

Rosmarinic acid is a water-soluble ester of caffeic acid and 3,4-dihydroxyphenyllactic acids, and is mainly found in plant species including Boraginaceae and Lamiaceae. In this research, we determined the inhibition property of rosmarinic acid on carbonic anhydrase isoenzymes I and II (hCA I and II) purified from human erythrocytes by using Sepharose-4B affinity column chromatography. hCA I and II isoenzymes were obtained with a yield of 57.9% and 67.2% and 76.5- and 509.3-fold purification of each isoenzyme, respectively. In order to show the purity of the isoenzymes, SDS-PAGE was performed and one band was observed. In vitro inhibition of both …