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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
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 …
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
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
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
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 …
Aqueous Dabco, An Efficient Medium For Rapid Organocatalyzed Knoevenagel Condensation And The Gewald Reaction, Mohammad Saeed Abaee, Somayeh Cheraghi
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
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.
Effects Of Functional Groups Of Triple Bonds Containing Molecules On Nickel Electroplating, Esma Sezer, Belkiz Ustamehmetoğlu, Ramazan Katirci
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 …
Binding Of Flavanone With \Beta-Cd/Ctdna: A Spectroscopic Investigation, Chandrasekaran Sowrirajan, Sameena Yousuf, Muthu Vijayan Enoch Israel Vijayaraj
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 …
N-Heterocyclic Carbene (Nhc) Palladium(Ii) Complexes Bearing Chiral Oxazoline Ligands And Their Catalytic Activities In Allylic Alkylation Reactions, Serpi̇l Deni̇zalti, Hayati̇ Türkmen, Beki̇r Çeti̇nkaya
N-Heterocyclic Carbene (Nhc) Palladium(Ii) Complexes Bearing Chiral Oxazoline Ligands And Their Catalytic Activities In Allylic Alkylation Reactions, Serpi̇l Deni̇zalti, Hayati̇ Türkmen, Beki̇r Çeti̇nkaya
Turkish Journal of Chemistry
NHC--Pd(II) complexes bearing a chiral oxazoline ligand (IIIa--f) were synthesized by cleavage of dimeric palladium complexes with the oxazoline ligand. They were fully characterized by ^1H and ^{13}C NMR and elemental analyses. The catalytic activity of the complexes (IIIa--f) in allylic alkylation reactions was evaluated. The complex IIIa was found to be the most active catalyst. Very low ee values indicate that the oxazoline is dissociated from the active catalytic species.
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
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.
Td-Dft Calculations And Mcd Spectroscopy Of Porphyrin And Phthalocyanine Analogues: Rational Design Of Photosensitizers For Pdt And Nir Region Sensor Applications, John Mack, Martijn Wildervanck, Tebello Nyokong
Td-Dft Calculations And Mcd Spectroscopy Of Porphyrin And Phthalocyanine Analogues: Rational Design Of Photosensitizers For Pdt And Nir Region Sensor Applications, John Mack, Martijn Wildervanck, Tebello Nyokong
Turkish Journal of Chemistry
Geometry optimizations and TD-DFT calculations have been carried out on series of fused-ring-expanded phthalonitriles, phthalocyanines, and aza-dipyrromethene boron difluoride (aza-BODIPY) dyes and trends in their optical and redox properties have been analyzed. The potential utility of fused-ring-expanded phthalocyanine and aza-BODIPY analogues for photodynamic therapy and near infrared region sensor applications is assessed on this basis. Recent attempts to prepare fused-ring-expanded aza-BODIPY analogues with benzene, pyrazine, and naphthalene rings have demonstrated that the properties of aza-BODIPYs vary markedly when different fused ring systems are added to the \beta-carbons of the pyrrole rings. A comparison of the TD-DFT calculations demonstrates that, as …
Electrochemistry Of Fe(Iv) And Mn(Iv) Corroles Containing Meso-Dichlorophenyl Substituents And The Use Of These Compounds As Catalysts For The Electroreduction Of Dioxygen In Acid Media, Lina Ye, Zhongping Ou, Deying Meng, Mingzhu Yuan, Yuanyuan Fang, Karl M. Kadish
Electrochemistry Of Fe(Iv) And Mn(Iv) Corroles Containing Meso-Dichlorophenyl Substituents And The Use Of These Compounds As Catalysts For The Electroreduction Of Dioxygen In Acid Media, Lina Ye, Zhongping Ou, Deying Meng, Mingzhu Yuan, Yuanyuan Fang, Karl M. Kadish
Turkish Journal of Chemistry
Two meso-dichlorophenyl substituted metallocorroles were synthesized and characterized as to their electrochemical and spectroelectrochemical properties in dichloromethane, benzonitrile, and pyridine containing 0.1 M tetra-n-butylammonium perchlorate (TBAP) as supporting electrolyte. The examined compounds are represented as (Cl_2Ph)_3CorFe^{IV}Cl and (Cl_2Ph)_3CorMn^{IV}Cl where (Cl_2Ph)_3Cor is the trianion of 5,10,15-tri(2,4-dichlorophenyl)corrole. Each metallocorrole was examined as to its catalytic activity for the electoreduction of dioxygen when coated on an edge-plane pyrolytic graphite electrode in 1.0 M HClO_4. Cyclic voltammetry combined with linear sweep voltammetry at a rotating disk electrode (RDE) and a rotating ring disk electrode (RRDE) was utilized to evaluate the catalytic activity for the …
Selective Synthesis Of Cyclododec-2-En-1-Yl Ethers Via Palladium-Catalyzed Allylic Substitution Reaction: A Kinetic Study, Asen Kolev, Magdalena Mitkova, Stefan Kotov, Encho Balbolov
Selective Synthesis Of Cyclododec-2-En-1-Yl Ethers Via Palladium-Catalyzed Allylic Substitution Reaction: A Kinetic Study, Asen Kolev, Magdalena Mitkova, Stefan Kotov, Encho Balbolov
Turkish Journal of Chemistry
The palladium-catalyzed reaction between isomeric cyclododec-2-en-1-yl acetates and primary aliphatic alcohols was found to result in high yields of the reaction products obtained. The selectivity with respect to cyclododec-2-en-1-yl ethers formed as reaction products ranged from 73% to 93%. The kinetics of the reaction of acetoxycyclododec-2-enes with alcohols was studied within the temperature range of 328--358 K. A kinetic equation best fitting the experimental data was provided.
The Chemistry Concerned With The Sonochemical-Assisted Synthesis Of Ceo_2/Poly(Amic Acid) Nanocomposites, Shiva Yazdani, Mehdi Hatami, Seyed Mohammad Vahdat
The Chemistry Concerned With The Sonochemical-Assisted Synthesis Of Ceo_2/Poly(Amic Acid) Nanocomposites, Shiva Yazdani, Mehdi Hatami, Seyed Mohammad Vahdat
Turkish Journal of Chemistry
A series of new poly(amic acid) (PAA) surface-modified cerium oxide (CeO_2) nanocomposites were prepared by sonochemical-assisted method. In the first step, treatment of the surface of CeO_2 nanoparticles with hexadecyltrimethoxysilane as a surface modifier was achieved. In the second step, the partially surface-treated nanoparticles were incorporated into PAA by different weight from 4% to 12%. PAA was synthesized by polycondensation reaction of benzophenone tetracarboxylic dianhydride and 3,5-diamino-N-(4-hydroxyphenyl) benzamide in N-methyl-2-pyrrolidone. The chemical structure of PAA was confirmed by ^1H NMR and FTIR spectroscopy. The polymer had an inherent viscosity of 0.38 dL/g. Three PAA/CeO_2 nanocomposite formulations were prepared from the …
Application Of Guanidine And Its Salts In Multicomponent Reactions, Mahshid Rahimifard, Ghodsi Mohammadi Ziarani, Boshra Malekzadeh Lashkariani
Application Of Guanidine And Its Salts In Multicomponent Reactions, Mahshid Rahimifard, Ghodsi Mohammadi Ziarani, Boshra Malekzadeh Lashkariani
Turkish Journal of Chemistry
This review gives an overview of the application of guanidine and its salts in multicomponent reactions. It can act as a catalyst or solvent for multicomponent reactions or as a reagent for synthesis of substituted diazines, triazines, and macroheterocycles by multicomponent reactions.
An Efficient Synthesis Of Some New Bisbenzimidazoles Via Microwave Technique, Bahi̇tti̇n Kahveci̇, Nesri̇n Karaali̇, Fati̇h Yilmaz, Emre Menteşe
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.
Novel N-Acyl/Aroyl-2-(5-Phenyl-2h-Tetrazol-2-Yl)Acetohydrazides: Synthesis And Characterization, Aamer Saeed, Majid Hussain, Muhammad Qasim
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.
Te(Ii)-Induced Heterocyclization Of 1,2-Alkadienephosphonates, Dobromir Dimitrov Enchev
Te(Ii)-Induced Heterocyclization Of 1,2-Alkadienephosphonates, Dobromir Dimitrov Enchev
Turkish Journal of Chemistry
The reactivity of some 1,2-alkadienephosphonates towards phenyltelluryl halides was investigated. A plausible mechanism of the reaction is discussed.
Facile Synthesis Of 5-Bromotropono[C]-Fused Pyrazoles And Isoxazole, Yang Li, Liangyu Xu, Wentao Gao
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
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 …
Crystal Growth Morphology Of Magnesium Hydroxide, Jiansong Wu, Juan Du, Yi-Min Gao
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 …
Deposition And Characterization Of Cu_9s_5 Nanocrystals From Unsymmetrical [(Hex)(Me)Nc(S)Nc(O)C_6h_3(No_2)_2-3,5]_2cu(Ii) And [(Et)(Bu)Nc(S)Nc(O)C_6h_4-4-No_2]_2cu(Ii) Complexes By Colloidal Thermolysis Method, Sohail Saeed, Rizwan Hussain
Deposition And Characterization Of Cu_9s_5 Nanocrystals From Unsymmetrical [(Hex)(Me)Nc(S)Nc(O)C_6h_3(No_2)_2-3,5]_2cu(Ii) And [(Et)(Bu)Nc(S)Nc(O)C_6h_4-4-No_2]_2cu(Ii) Complexes By Colloidal Thermolysis Method, Sohail Saeed, Rizwan Hussain
Turkish Journal of Chemistry
Cu_9S_5 nanocrystals were synthesized from unsymmetrical [(Hex)(Me)NC(S)NC(O)C_6H_3(NO_2)_2-3,5]_2Cu(II) and [(Et)(Bu)NC(S)NC(O)C_6H_4-4-NO_2]_2 Cu(II) complexes by colloidal thermolysis in the presence of surfactant oleylamine. The unsymmetrical copper complexes were synthesized by the reaction of copper(II) acetate with N-[hexyl(methyl)carbamothioyl]-3,5-dinitrobenzamide and N-[ethyl(butyl)carbamothioyl]-4-nitrobenzamide. The complexes were used as single-source precursors for the preparation of Cu_9S_5 nanocrsytals. The Cu_9S_5 nanocrystals were characterized by X-ray powder diffraction and transmission electron microscopy.
Investigation Of The Adsorption Kinetics Of Methylene Blue Onto Cotton Wastes, Bi̇lal Acemi̇oğlu, Murat Ertaş, Mehmet Hakki Alma, Mustafa Usta
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 …
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
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 …
In Vitro Effects Of Pesticide Exposure On The Activity Of The Paraoxonase-1 Enzyme From Sheep Liver Microsomes, Büşra Cebeci̇, Zuhal Alim, Şükrü Beydemi̇r
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 Co Methanation Over Ceo_2--Zro_2-Composed Nio And Co_3o_4 Catalysts, Fi̇li̇z Derekaya, Derya Ermergen
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 …
Synthesis, Spectral Characterisation, Electrochemical, And Fluorescence Studies Of Biologically Active Novel Schiff Base Complexes Derived From E-4-(2-Hydroxy-3-Methoxybenzlideneamino)-N-(Pyrimidin-2-Yl)Benzenesulfonamide, Valarmathy Govindaraj, Subbalakshmi Ramanathan
Synthesis, Spectral Characterisation, Electrochemical, And Fluorescence Studies Of Biologically Active Novel Schiff Base Complexes Derived From E-4-(2-Hydroxy-3-Methoxybenzlideneamino)-N-(Pyrimidin-2-Yl)Benzenesulfonamide, Valarmathy Govindaraj, Subbalakshmi Ramanathan
Turkish Journal of Chemistry
A new Schiff base was prepared from 2-sulphanilamidopyrimidine and 2-hydroxy-3-methoxybenzaldehyde in ethanolic media and it was complexed with Mn(II), Co(II), Ni(II), Cu(II), and Zn(II) ions. The synthesised ligand and complexes were characterised by IR, UV, ^1H and ^{13}C NMR, elemental analysis, cyclic voltammetry, EPR, molar conductance, and magnetic susceptibility. The reasonable shifts in FT-IR and NMR spectral signals of the complexes with respect to the free ligand confirm good coordination of the Schiff-base ligand with the metal through imine nitrogen and oxygen atoms of Schiff base moiety. The Schiff-base ligand and the complexes were screened for antimicrobial activity and fluorescent …
Adsorption Of The Urea Molecule On The B_{12}N_{12} Nanocage, Mohammad Taghi Baei
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 …
Antioxidant, Anticholinesterase, And Antimicrobial Activities And Fatty Acid Constituents Of Achillea Cappadocica Hausskn. Et Bornm., Abdulselam Ertaş, Mehmet Boğa, Nesri̇n Haşi̇mi̇, Yeter Yeşi̇l, Ahmet Ceyhan Gören, Gülaçti Topçu, Ufuk Kolak
Antioxidant, Anticholinesterase, And Antimicrobial Activities And Fatty Acid Constituents Of Achillea Cappadocica Hausskn. Et Bornm., Abdulselam Ertaş, Mehmet Boğa, Nesri̇n Haşi̇mi̇, Yeter Yeşi̇l, Ahmet Ceyhan Gören, Gülaçti Topçu, Ufuk Kolak
Turkish Journal of Chemistry
This study was the first fatty acid analysis and biological activity report on an endemic Achillea species, Achillea cappadocica Hausskn. et Bornm. The major compounds in the fatty acid were identified as oleic (34.7 %), palmitic (23.1 %), and linoleic acids (20.6 %). The methanol and water extracts indicated higher ABTS cation radical scavenging activity than that of \alpha-tocopherol and BHT at 100 \mu g/mL. The acetone extract showed 70.62 % inhibitory activity against butyrylcholinesterase at 200 \mu g/mL. The acetone and methanol extracts exhibited moderate antimicrobial activity.
Development Of 2-Acetylpyridine-4-Phenyl-3-Thiosemicarbazone Functionalized Polymeric Resin For The Preconcentration Of Metal Ions Prior To Their Ultratrace Determinations By Mis-Faas, Ali Nawaz Siyal, Saima Qayoom Memon, Aydan Elçi̇, Ümi̇t Di̇vri̇kli̇, Muhammad Yar Khuhawar, Lati̇f Elçi̇
Development Of 2-Acetylpyridine-4-Phenyl-3-Thiosemicarbazone Functionalized Polymeric Resin For The Preconcentration Of Metal Ions Prior To Their Ultratrace Determinations By Mis-Faas, Ali Nawaz Siyal, Saima Qayoom Memon, Aydan Elçi̇, Ümi̇t Di̇vri̇kli̇, Muhammad Yar Khuhawar, Lati̇f Elçi̇
Turkish Journal of Chemistry
2-Acetylpyridine-4-phenyl-3-thiosemicarbazone (APPT) ligand was incorporated onto Amberlite XAD-2 resin through an azo spacer and characterized by FTIR spectroscopy, elemental analysis, TGA, and SEM analysis. The synthesized resin was used for the preconcentration of Pb(II), Zn(II), Co(II), Ni(II), Cu(II), and Cd(II) ions. The sorbed metal ions were eluted with 10 mL of 2.0 mol L^{-1} HCl and determined by microsample injection coupled flame atomic spectrometry (MIS-FAAS). The recoveries of studied metal ions were \ge 95.1 % with RSD \ge 4.0 % at optimum pH 8; resin amount, 300 mg; flow rates, 2.0 mL min^{-1} (of eluent) and 3.0 mL min^{-1} (sample …