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Full-Text Articles in Physical Sciences and Mathematics

Study Of The Interaction Between Glucosamine Hydrochloride And Sodium Dodecylsulphate Micelles Using Conductometric, Isothermal Calorimetry, Zeta-Potential Titrations, And Nmr Noesy, Marcos Roberto Abreu Alves, Luciano Sindra Virtuoso, Elson Santiago De Alvarenga, Ângelo Márcio Leite Denadai Jan 2014

Study Of The Interaction Between Glucosamine Hydrochloride And Sodium Dodecylsulphate Micelles Using Conductometric, Isothermal Calorimetry, Zeta-Potential Titrations, And Nmr Noesy, Marcos Roberto Abreu Alves, Luciano Sindra Virtuoso, Elson Santiago De Alvarenga, Ângelo Márcio Leite Denadai

Turkish Journal of Chemistry

The aim of this work was to investigate the influence of an anti-inflammatory agent, the bulky counterion named glucosamine (Gl^+), in sodium dodecylsulphate (SDS) in 2 ways: 1) by titration of SDS solutions with different concentrations of Gl^+; and 2) by titration of Gl^+ with SDS solution with concentration close to the critical micellar concentration (cmc) (7.7 mM). In procedure 1, micellisation study by isothermal titration calorimetry (ITC) showed that the increase in Gl^+ concentration reduces the cmc and the micellisation enthalpy. Increasing of the micellisation entropy was also observed, suggesting desolvation of micellar structures as a consequence of electrostatic …


Optimization Of Lifepo_4 Synthesis By Hydrothermal Method, Muhsi̇n Mazman, Ömür Çuhadar, Davut Uzun, Ercan Avci, Emre Bi̇çer, Tevhi̇t Cem Kaypmaz, Ümüt Kadi̇roğlu Jan 2014

Optimization Of Lifepo_4 Synthesis By Hydrothermal Method, Muhsi̇n Mazman, Ömür Çuhadar, Davut Uzun, Ercan Avci, Emre Bi̇çer, Tevhi̇t Cem Kaypmaz, Ümüt Kadi̇roğlu

Turkish Journal of Chemistry

Optimization of the LiFePO_4 cathode active material synthesis process in the hydrothermal method consists of many factors, including pH, carbon coating, particle size optimization, sintering and hydrothermal synthesis temperature. The main goal of this study is to determine the effect of particle size, pH and carbon coating on capacity and cycle performance. In this study, LiFePO_4 cathode active materials were prepared at different pH (6.5 and 8.5) and temperature (160 and 180 °C) levels using the hydrothermal method. The hydrothermal synthesis products were sintered at 400, 500, 600, and 700 °C with 5% and 7% carbon source. The initial discharge …


Aryl Butenoic Acid Derivatives As A New Class Of Histone Deacetylase Inhibitors: Synthesis, In Vitro Evaluation, And Molecular Docking Studies, Peruze Ayhan Eşi̇yok, Özlem Seven, Gülüzar Eymur, Gamze Bora Tatar, Di̇dem Dayangaç Erden, Kemal Yelekçi̇, Hayat Yurter, Ayhan Sitki Demi̇r Jan 2014

Aryl Butenoic Acid Derivatives As A New Class Of Histone Deacetylase Inhibitors: Synthesis, In Vitro Evaluation, And Molecular Docking Studies, Peruze Ayhan Eşi̇yok, Özlem Seven, Gülüzar Eymur, Gamze Bora Tatar, Di̇dem Dayangaç Erden, Kemal Yelekçi̇, Hayat Yurter, Ayhan Sitki Demi̇r

Turkish Journal of Chemistry

New aryl butenoic acid derivatives have been synthesized by combining hydroxy- or methoxy-substituted phenyl rings as the capping group, with a double bond in the short linker as well as metal binding groups, enoic ester, and salts bearing either methyl or morpholine. These compounds have been shown to possess promising histone deacetylase inhibition activities via in vitro fluorometric assay and molecular docking studies.


Synthesis And Characterization Of New Metallophthalocyanines Containing O_4s_2 Mixed-Donor Substituted Macrocyclic Groups, Meltem Betül Kiliçaslan, Hali̇t Kanteki̇n Jan 2014

Synthesis And Characterization Of New Metallophthalocyanines Containing O_4s_2 Mixed-Donor Substituted Macrocyclic Groups, Meltem Betül Kiliçaslan, Hali̇t Kanteki̇n

Turkish Journal of Chemistry

New phthalocyanine compounds containing mixed-donor substituted macrocyclic groups were synthesized. The complexes of metal phthalocyanines 3--5 were prepared by the reaction of 2 to get dinitrile derivative complexes by means of the corresponding anhydrous metal salts. Structures of the new compounds were characterized by IR, ^1H NMR, ^{13}C NMR, elemental analysis, and MS spectral data.


Platinum Or Nickel Nanoparticles Decorated On Silica Spheres By Microwave Irradiation Technique, Ayşe Bayrakçeken Jan 2014

Platinum Or Nickel Nanoparticles Decorated On Silica Spheres By Microwave Irradiation Technique, Ayşe Bayrakçeken

Turkish Journal of Chemistry

Supported catalysts are of great interest because of their wide range of application possibilities. In this study, firstly silica spheres were synthesized and then platinum and nickel nanoparticles were incorporated on this silica by microwave irradiation, which is an efficient technique for catalyst preparation. Synthesized silica spheres and catalysts were characterized by BET, X-ray diffraction, Fourier transform infrared spectroscopy, thermogravimetric analysis, and transmission electron microscopy techniques. Pt or Ni nanoparticles well dispersed over silica support were obtained using microwave irradiation.


Crystal Growth Morphology Of Magnesium Hydroxide, Jiansong Wu, Juan Du, Yi-Min Gao Jan 2014

Crystal Growth Morphology Of Magnesium Hydroxide, Jiansong Wu, Juan Du, Yi-Min Gao

Turkish Journal of Chemistry

In this paper, the formation process of magnesium hydroxide unit cells, as well as the structural characteristics and growth morphology of magnesium hydroxide, is discussed from the perspective of growth units. The growth process of the hexagonal structure of the magnesium hydroxide is as follows: the growth units are first incorporated into a larger hexagonal dimension unit on the same plane, and then the hexagonal layers connect to each other in the z-axis direction for the hexagonal magnesium hydroxide unit cell. The results of the study show that the model of anion coordination polyhedron growth units may be reasonably deduced …


Preparation And Characterization Of Nonmetal Promoter Modified Cuznal Catalysts For Higher Alcohol From Synthesis Gas Through Complete Liquid Phase Method, Shirui Yu, Xiaodong Wang, Wei Huang Jan 2014

Preparation And Characterization Of Nonmetal Promoter Modified Cuznal Catalysts For Higher Alcohol From Synthesis Gas Through Complete Liquid Phase Method, Shirui Yu, Xiaodong Wang, Wei Huang

Turkish Journal of Chemistry

A complete liquid phase technology and a function regulator were applied to prepare CuZnAl catalysts for higher alcohol synthesis. Characterizations showed that the introduction of the function regulator can change the reduction ability of copper oxides and the surface basicity of catalysts. Activity tests indicated that the selectivity of higher alcohol is high when considerable medium-strong basicity and the synergistic effects of copper ion and metal copper exist on the catalytic surface. The optimized modified CuZnAl catalyst without any metal additives provides a CO conversion of 28.9%, C_{2+}OH selectivity of up to 42.8%, and hydrocarbon selectivity of 2.5%, with a …


Novel N-Acyl/Aroyl-2-(5-Phenyl-2h-Tetrazol-2-Yl)Acetohydrazides: Synthesis And Characterization, Aamer Saeed, Majid Hussain, Muhammad Qasim Jan 2014

Novel N-Acyl/Aroyl-2-(5-Phenyl-2h-Tetrazol-2-Yl)Acetohydrazides: Synthesis And Characterization, Aamer Saeed, Majid Hussain, Muhammad Qasim

Turkish Journal of Chemistry

A number of novel N-acyl/aroyl-2-(5-phenyl-2H-tetrazol-2-yl)acetohydrazides (4a--j) of biological interest were efficiently synthesized by treating 2-(5-phenyl-2H-tetrazole-2-yl)acetohydrazide (3) with a variety of aroyl/hetero- cyclyl or alkanoyl chlorides. FTIR, ^1H NMR, ^{13}C NMR, GC-MS, and elemental analyses data confirmed the structures assigned to the newly synthesized compounds.


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 …


An Efficient Synthesis Of Some New Bisbenzimidazoles Via Microwave Technique, Bahi̇tti̇n Kahveci̇, Nesri̇n Karaali̇, Fati̇h Yilmaz, Emre Menteşe Jan 2014

An Efficient Synthesis Of Some New Bisbenzimidazoles Via Microwave Technique, Bahi̇tti̇n Kahveci̇, Nesri̇n Karaali̇, Fati̇h Yilmaz, Emre Menteşe

Turkish Journal of Chemistry

2,2'-[1,4 (1,3)-Phenylenedi(methylene)]bis-1H-benzimidazole derivatives were obtained from the reaction of 1,4- or (1,3)-bisiminoester hydrochloride and o-phenylenediamine derivatives under microwave irradiation. Ester and hydrazide derivatives were prepared from a free NH group. This practical method revealed good results for yield, reaction time, and quick isolation of products.


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.


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, …


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.


Partial Purification And Biochemical Characterization Of An Extremely Thermo- And Ph-Stable Esterase With Great Substrate Affinity, Esra Özbek, Yakup Kolcuoğlu, Leyla Konak, Ahmet Çolak, Fulya Öz Jan 2014

Partial Purification And Biochemical Characterization Of An Extremely Thermo- And Ph-Stable Esterase With Great Substrate Affinity, Esra Özbek, Yakup Kolcuoğlu, Leyla Konak, Ahmet Çolak, Fulya Öz

Turkish Journal of Chemistry

An esterase from a thermophilic bacterium, Geobacillus sp. DF20, was partially purified. Final purification factor was found to be 64.5-fold using Q-Sepharose ion exchange column chromatography. Native polyacrylamide gel electrophoresis indicated the presence of a single active esterase. The substrate specificity of this esterase was high for p-nitrophenyl butyrate (pNPB) substrate. The optimum pH and temperature for the enzyme activity were 7.0 and 50 ^°C, respectively. The pH and heat stability profiles show that this enzyme is more stable under neutral conditions at 50 ^°C. K_m and V_{max} values for this esterase acting on pNPB were 0.12 mM and 54.6 …


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 %).


Adsorption Of The Urea Molecule On The B_{12}N_{12} Nanocage, Mohammad Taghi Baei Jan 2014

Adsorption Of The Urea Molecule On The B_{12}N_{12} Nanocage, Mohammad Taghi Baei

Turkish Journal of Chemistry

The adsorption of the urea molecule on the external surface of the B_{12}N_{12} nanocage was investigated using density functional theory (DFT) calculations. Adsorption of urea on the nanocage releases energies of about --23.70 to --29.50 kcal/mol with a significant NBO charge transfer from the urea to the nanocage. It was also found that the urea molecule can be strongly chemisorbed on the surface of the nanocage with Gibbs free energies of -7.91 to -14.81 kcal/mol. The HOMO--LUMO gap of the nanocage does not change significantly upon urea adsorption, while the Fermi level is dramatically changed from -4.27 eV in the …


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 …


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 …


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.


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 …


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, …


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 …


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 …


The Effects Of Ionic Strength And Temperature On The Dissociation Constants Of Adefovir And Cidofovir Used As Antiviral Drugs, Hasan Atabey, Hayati̇ Sari Jan 2014

The Effects Of Ionic Strength And Temperature On The Dissociation Constants Of Adefovir And Cidofovir Used As Antiviral Drugs, Hasan Atabey, Hayati̇ Sari

Turkish Journal of Chemistry

The effects of ionic strength and temperature on the dissociation constants of adefovir (PMEA) and cidofovir (HPMPC) used as antiviral drugs were studied at 298 K, 308 K, and 318 K in aqueous media and at different ionic strength backgrounds of NaCl potentiometrically. The dissociation constants of the ligands were determined via the calculation of the titration data with the SUPERQUAD computer program. The thermodynamic parameters (\Delta G, \Delta H, and \Delta S) for all species were calculated. The dissociation order of nitrogen and oxygen atoms in the ligands according to proton affinities values were obtained using PM6 semiempirical methods. …


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 …


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.