Open Access. Powered by Scholars. Published by Universities.®
Physical Sciences and Mathematics Commons™
Open Access. Powered by Scholars. Published by Universities.®
- Keyword
-
- Palladium (8)
- 1 (5)
- Anticancer activity (4)
- Catalyst (4)
- N-heterocyclic carbene (4)
-
- 2 (3)
- 3 (3)
- Adsorption (3)
- Electrochemical impedance spectroscopy (3)
- Ionic liquid (3)
- Resorcinarene (3)
- Synthesis (3)
- $N$-heterocyclic carbene (2)
- Antibiotic (2)
- Antimicrobial activity (2)
- Biosensor (2)
- Calixarene (2)
- Catalysis (2)
- Cavitand (2)
- Copper complex (2)
- Electrochemistry (2)
- Electrospinning (2)
- Fluorescence (2)
- Fuel cells (2)
- Heck reaction (2)
- Magnetic nanoparticles (2)
- Metal (2)
- Microgels (2)
- Microwave (2)
- Microwave-assisted synthesis (2)
Articles 91 - 106 of 106
Full-Text Articles in Physical Sciences and Mathematics
Secondary Metabolites From Sambucus Ebulus, İrem Atay, Hasan Kirmizibekmez, Ahmet Ceyhan Gören, Erdem Yeşi̇lada
Secondary Metabolites From Sambucus Ebulus, İrem Atay, Hasan Kirmizibekmez, Ahmet Ceyhan Gören, Erdem Yeşi̇lada
Turkish Journal of Chemistry
A new nonglycosidic iridoid, sambulin B (1), was isolated from the methanol extract of Sambucus ebulus L. leaves along with a recently reported new nonglycosidic iridoid, 10-O-acetylpatrinoside aglycone (sambulin A) (2); 2 flavonoids, isorhamnetin-3-O-\beta-D-glucopyranoside (3) and isorhamnetin-3-O-rutinoside (4); and a mixture of 2 flavonoids (5), quercetin-3-O-\beta-D-glucopyranoside and quercetin-3-O-\beta-D-galactopyranoside. Their structures were elucidated by 1-D and 2-D nuclear magnetic resonance spectroscopy (NMR) and mass spectrometry (MS) experiments.
Amperometric Biosensing Of Ethanol Based On Integration Of Alcohol Dehydrogenase With A Pt/Ppy--Pvs/Mb Electrode, Özlem Çolak, Fatma Arslan
Amperometric Biosensing Of Ethanol Based On Integration Of Alcohol Dehydrogenase With A Pt/Ppy--Pvs/Mb Electrode, Özlem Çolak, Fatma Arslan
Turkish Journal of Chemistry
A novel amperometric ethanol biosensor with alcohol dehydrogenase (ADH) and nicotinamide adenine dinucleotide (NAD^+) on polypyrrole--polyvinylsulfonate (PPy-PVS) film was accomplished. Meldola's blue (MB) was used as a mediator; it can facilitate the electron transfer that involves a chemical interaction between the electrode surface and NADH. Determination of ethanol was carried out by the oxidation of MB at --0.072 V vs. Ag/AgCl. The effects of pH and temperature were investigated and optimum parameters were found to be 7.0 and 40 °C, respectively. There are 2 linear parts at 1.0 \mu M--10.0 \mu M (R^2 = 0.993) and 0.01 mM--0.1 mM (R^2 …
Purification And Characterization Of Nadph-Cytochrome P450 Reductase From Lake Van Fish Liver Microsomes And Investigation Of Some Chemical And Metals' Effects On The Enzyme Activity, Müslüm Kuzu, Mehmet Çi̇ftci̇
Purification And Characterization Of Nadph-Cytochrome P450 Reductase From Lake Van Fish Liver Microsomes And Investigation Of Some Chemical And Metals' Effects On The Enzyme Activity, Müslüm Kuzu, Mehmet Çi̇ftci̇
Turkish Journal of Chemistry
NADPH-cytochrome P450 reductase was purified from Lake Van fish liver microsomes by primary and secondary DEAE-cellulose column chromatograph with 20.46 \mu M/min/mg enzyme specific activities, 54.4% purification yield, and purification of 38-fold. The purity of the enzyme was established, and its monomer molecular weight was determined by SDS-polyacrylamide gel electrophoresis. SDS-PAGE results showed a single band and the molecular weight of NADPH-cytochrome P450 reductase was 70 kDa. In addition, optimum ionic strength, optimum pH, optimum temperature, and stable pH values were determined for the enzyme in the kinetic studies performed. K_M and V_{max} were determined for NADPH and cytochrome c. …
Synthesis Of Methyl 4-(9h-Carbazole-9-Carbanothioylthio) Benzoate: Electropolymerization And Impedimetric Study, Murat Ateş, Nesi̇mi̇ Uludağ, Fati̇h Arican, Tolga Karazehi̇r
Synthesis Of Methyl 4-(9h-Carbazole-9-Carbanothioylthio) Benzoate: Electropolymerization And Impedimetric Study, Murat Ateş, Nesi̇mi̇ Uludağ, Fati̇h Arican, Tolga Karazehi̇r
Turkish Journal of Chemistry
Methyl 4-((9H-(carbazole-9-carbanothioylthio) benzoate (MCzCTB) was chemically synthesized and characterized by FTIR, ^1H NMR, and ^{13}C NMR. A novel synthesized monomer was electropolymerized on a glassy carbon electrode (GCE) in various initial molar concentrations of [MCzCTB]_0= 1, 3, 5, and 10 mM in 0.1 M NaClO_4/CH_3CN and 1 M H_2SO_4. P(MCzCTB)/GCE was characterized by cyclic voltammetry, Fourier transform infrared-attenuated transmittance reflectance, scanning electron microscopy-energy dispersive X-ray, and electrochemical impedance spectroscopy. The capacitive behavior of the modified electrode was obtained by Nyquist, Bode-magnitude, and Bode-phase plots. The highest capacitance at low frequency was obtained as \sim 53.1 mF cm^{-2} from Nyquist plot …
Synthesis, Structural Characterization, And Antimicrobial Efficiency Of Sulfadiazine Azo-Azomethine Dyes And Their Bi-Homonuclear Uranyl Complexes For Chemotherapeutic Use, Abdalla M. Khedr, Fawaz A. Saad
Synthesis, Structural Characterization, And Antimicrobial Efficiency Of Sulfadiazine Azo-Azomethine Dyes And Their Bi-Homonuclear Uranyl Complexes For Chemotherapeutic Use, Abdalla M. Khedr, Fawaz A. Saad
Turkish Journal of Chemistry
Two sulfadiazine azo-azomethine dyes containing two active coordination centers and their bi-homonuclear UO_2(II)-complexes were synthesized for potential chemotherapeutic use. The ligands were prepared, starting from the coupling of sulfadiazine dizonium salt with acetylacetone, followed by condensation with ethylenediamine and 1,6-hexanediamine (HL^I and HL^{II}) using a modified literature procedure. The structures of the ligands and their UO_2(II)-complexes were elucidated by conventional and thermal gravimetric analyses, molar conductivity, magnetic susceptibility, and IR, UV-Vis, ^1H NMR, and mass spectra. The analytical and spectral data supported the binuclear formulation of the complexes with a 2:1 metal to ligand ratio and octahedral geometry. The molar …
The Synthesis Of 1,3-Dialkyl-4-Methylimidazolinium Salts And Their Application In Palladium Catalyzed Heck Coupling Reactions, Murat Yi̇ği̇t, Güli̇n Bayam, Beyhan Yi̇ği̇t, İsmai̇l Özdemi̇r
The Synthesis Of 1,3-Dialkyl-4-Methylimidazolinium Salts And Their Application In Palladium Catalyzed Heck Coupling Reactions, Murat Yi̇ği̇t, Güli̇n Bayam, Beyhan Yi̇ği̇t, İsmai̇l Özdemi̇r
Turkish Journal of Chemistry
Seven novel 1,3-dialkyl-4-methylimidazolinium chloride salts 3a--g were prepared as precursors of N-heterocyclic carbenes by reacting N,N'-alkyl-1,2-diaminopropane, triethyl orthoformate, and ammonium chloride. The salts were characterized spectroscopically. The in situ prepared palladium complexes derived from the imidazolinium salts and palladium acetate were used as catalyst in Heck coupling reactions between aryl bromides and styrene. The corresponding Heck products were obtained in good yields.
Selective Co Methanation Over Nio--Al_2o_3--Zro_2 And Co_3o_4--Al_2o_3--Zro_2 Catalysts, Fi̇li̇z Derekaya, Derya Ermergen
Selective Co Methanation Over Nio--Al_2o_3--Zro_2 And Co_3o_4--Al_2o_3--Zro_2 Catalysts, Fi̇li̇z Derekaya, Derya Ermergen
Turkish Journal of Chemistry
NiO--Al_2O_3--ZrO_2 and Co_3O_4--Al_2O_3--ZrO_2 catalysts were prepared by three different co-precipitation methods, namely co-precipitation, surfactant-assisted co-precipitation, and surfactant-assisted co-precipitation with ultrasound mixing methods, and their activities were tested in selective CO methanation. Catalysts were characterized using N_2 physisorption, XRD, SEM, TEM, XPS, and TPR-H_2 techniques. CO methanation and selective CO methanation reactions were carried out. Catalysts prepared by surfactant assisted co-precipitation gave high surface area, uniform pore size distributions, and small pores. The NiO--Al_2O_3--ZrO_2 catalyst prepared by surfactant-assisted co-precipitation gave 50% CO conversion to CH_4 at 155 °C and all CO converted to CH_4 when T > 225 °C. For the selective …
Redox Polymerization Of N-Isopropylacrylamide By Using Hydroxylated Soya Oil Polymer, Abdulkadi̇r Alli, Ti̇mur Şanal, Baki̇ Hazer
Redox Polymerization Of N-Isopropylacrylamide By Using Hydroxylated Soya Oil Polymer, Abdulkadi̇r Alli, Ti̇mur Şanal, Baki̇ Hazer
Turkish Journal of Chemistry
Water soluble hydroxylated soya oil polymer was used in the redox polymerization of N-isopropylacrylamide (NIPAM) in order to obtain water-based hydroxylated-soya oil polymer-g-PNIPAM graft copolymer. For this purpose, soya oil was exposed to air under sunlight to obtain autoxidized soya oil polymer (PSy-ox). PSy-ox was allowed to react with diethanol amine to obtain hydroxylated soya oil polymer (hydroxylated-PSy). An ammonium persulfate with hydroxylated-PSy redox initiating system was used in the polymerization of NIPAM in order to obtain thermo-responsive hydroxylated-PSy-g-PNIPAM water-based graft copolymers. The graft copolymers were characterized using proton nuclear magnetic resonance, Fourier transform infrared~spectroscopy, gel permeation chromatography, thermal gravimetric …
Gaseous And Dissolved Oxygen Sensing With Stabilized Pyrene In Ionic Liquid Modified Electrospun Slides, Özlem Öter, Gülhan Sabanci Şahi̇n
Gaseous And Dissolved Oxygen Sensing With Stabilized Pyrene In Ionic Liquid Modified Electrospun Slides, Özlem Öter, Gülhan Sabanci Şahi̇n
Turkish Journal of Chemistry
Pyrene dye has many superior characteristics for oxygen sensing studies such as long fluorescence lifetime, high quantum yield, and good sensitivity. It is preferred in some cases over ruthenium dyes for its more lipophilic character and higher sensitivity. However, easy photodegradation of pyrene is a challenging problem. In this study, pyrene dye was for the first time immobilized in an ethyl cellulose matrix and used for oxygen sensing in the form of thin films and electrospun sensing slides. The hydrophobic ionic liquid 1-butyl-3-methylimidazolium hexafluorophosphate was used as additive for the first time for dissolved oxygen sensing studies. The oxygen sensitivity …
Synthesis, Characterization, And Metal Extraction Studies Of A New Macrobicyclic Ligand, Hali̇l Zeki̇ Gök, Yaşar Gök, Esra Eker
Synthesis, Characterization, And Metal Extraction Studies Of A New Macrobicyclic Ligand, Hali̇l Zeki̇ Gök, Yaşar Gök, Esra Eker
Turkish Journal of Chemistry
This article describes the synthesis, characterization, and metal ion binding properties of a new macrobicyclic ligand. Solvent extraction experiments were performed in order to determine the extraction behavior of new macrobicyclic ligand towards selected metal cations. Selective extraction of heavy metals and precious metals is highly demanded due to their toxicity and commercial importance. Based on our experimental results, macrobicyclic ligand 3 demonstrated remarkable affinity towards the Ag^+ ion by 96.7% and 96.9% to the dichloromethane and chloroform phases, respectively. The extraction experiments with macrobicyclic ligand 3 for the Ag^+ ion were repeated at different temperatures to calculate thermodynamic parameters. …
Two New Coordination Polymers Containing Dicyanidoargentate(I) And Dicyanidoaurate(I): Synthesis And Characterization, And A Detailed In Vitro Investigation Of Their Anticancer Activities On Some Cancer Cell Lines, Ali̇ Aydin, Ahmet Karadağ, Şaban Teki̇n, Nesri̇n Korkmaz, Aslihan Özdemi̇r
Two New Coordination Polymers Containing Dicyanidoargentate(I) And Dicyanidoaurate(I): Synthesis And Characterization, And A Detailed In Vitro Investigation Of Their Anticancer Activities On Some Cancer Cell Lines, Ali̇ Aydin, Ahmet Karadağ, Şaban Teki̇n, Nesri̇n Korkmaz, Aslihan Özdemi̇r
Turkish Journal of Chemistry
Two novel cyanido-bridged bimetallic polymeric complexes, [Ni(edbea)Ag$_{3}$(CN)$_{5}$]$_{n} $(C1) and [Ni(bishydeten) Au$_{2}$(CN)$_{4}$]$_{n}$ (C2), where edbea = [2,2$' $-(ethylenedioxy)bis(ethylamine)] and bishydeten = [($N$,$N' $-bis(2-hydroxyethyl) ethylenediamine)] are ligands, were synthesized and characterized by elemental, infrared, and thermal measurement techniques and investigated for their biological activity in cultured cancer cell lines. The results show that both compounds and free anions, [Ag(CN)$_{2}$]$^{-}$ and [Au(CN)$_{2}$]$^{-}$, exhibited very high antiproliferative activity compared to the anticancer drug 5FU against the cancer cell lines tested. The antiproliferative and cytotoxic activities of C1 and C2 were significantly lower than those of free anions, indicating that the extreme cytotoxicity of free …
Synthesis Of Bis-Thiazoles, Bis-Pyrazoles, Bis-Hydrazonates, And Bis-Triazolothiadiazoles Based On Bis-Hydrazonoyl And Bis-Hydrazones, Abdelwahed Sayed
Synthesis Of Bis-Thiazoles, Bis-Pyrazoles, Bis-Hydrazonates, And Bis-Triazolothiadiazoles Based On Bis-Hydrazonoyl And Bis-Hydrazones, Abdelwahed Sayed
Turkish Journal of Chemistry
A facile synthesis of bis-thiazoles, bis-pyrazoles, and bis-hydrazonates from the reaction of bis-hydrazonoyl dichlorides with different moieties is described. Bis-triazolothiadiazoles were synthesized via oxidative cyclization of bis-hydrazones. Structures of the final product were elucidated by elemental analyses and spectral data.
Kinetics Study And Influence Of Water-Soluble Polymer On The Electrodeposition Of Iron From A Citrate-Chloride Electrolyte On The Basis Of Fe(Iii), Vyacheslav Protsenko, Felix Danilov
Kinetics Study And Influence Of Water-Soluble Polymer On The Electrodeposition Of Iron From A Citrate-Chloride Electrolyte On The Basis Of Fe(Iii), Vyacheslav Protsenko, Felix Danilov
Turkish Journal of Chemistry
The kinetics of the iron electrodeposition reaction from a plating bath containing trivalent iron ions is investigated in the present work. The electrochemical reaction is stated to proceed via the formation of relatively stable intermediates: Fe(II) ions. Only a part of the total amount of Fe(II) ions formed at the first stage of Fe(III) discharge is reduced further, producing metal iron. The effect of polyhexamethyleneguanidine hydrochloride (with an average molecular weight of 1000) on the iron deposition is ascertained. The presence of polymer additive in the iron electrolyte appreciably affects the rate of iron deposition, while the polymer additive does …
Characterization Of A Cu$^{2+}$-Selective Fluorescent Probe Derived From Rhodamine B With 1,2,4-Triazole As Subunit And Its Application In Cell Imaging, Na Li, Chunwei Yu, Yuxiang Ji, Jun Zhang
Characterization Of A Cu$^{2+}$-Selective Fluorescent Probe Derived From Rhodamine B With 1,2,4-Triazole As Subunit And Its Application In Cell Imaging, Na Li, Chunwei Yu, Yuxiang Ji, Jun Zhang
Turkish Journal of Chemistry
A rhodamine B derivative containing 1,2,4-triazole as subunit was characterized as an "off-on" type Cu$^{2+}$-selective fluorescent probe. It exhibited high selectivity and sensitivity for Cu$^{2+}$ in ethanol-water solution (9:1, v:v, pH 7.0, 20 mM HEPES) and underwent ring opening. A prominent fluorescence enhancement at 570 nm was observed in the presence of Cu$^{2+}$ with the change in the absorption spectrum, and a 1:1 metal-ligand complex was formed. With the optimized experimental conditions, the probe exhibited a dynamic response range for Cu$^{2+}$ from 8.0 $\times $ 10$^{-7}$ to 7.5 $\times $ 10$^{-6}$ M with a detection limit of 2.3 $\times $ …
Acid-Free Synthesis Of S-Nitrosothiols At Neutral Ph By Shock-Freezing In Liquid Nitrogen, Dimitrios Tsikas, Anke Böhmer, Arne Trettin, Arslan Arinç Kayaçelebi̇
Acid-Free Synthesis Of S-Nitrosothiols At Neutral Ph By Shock-Freezing In Liquid Nitrogen, Dimitrios Tsikas, Anke Böhmer, Arne Trettin, Arslan Arinç Kayaçelebi̇
Turkish Journal of Chemistry
A laboratory method for the acid-free synthesis of S-nitrosothiols (RSNO) from NaNO$_{2}$ and thiols in aqueous buffer of neutral pH is reported. Equimolar amounts of NaNO$_{2}$ and thiol are added to a 100-$\mu $M Na$_{4}$EDTA-containing Na$_{2}$HPO$_{4}$ buffer (100 mM, pH 7.4). Samples are set into liquid nitrogen for 1 min and then thawed to room temperature or in an ice bath. Dependent upon the RSNO, repetition of the procedure may be required. This method may be of particular importance when the classical acid-based method fails or releases harmful gases such as H$_{2}$S.
Sustainable Activity Of Hydrothermally Synthesized Mesoporous Silicates In Acetic Acid Esterification, Veli̇ Şi̇mşek, Levent Deği̇rmenci̇, Kirali̇ Mürtezaoğlu
Sustainable Activity Of Hydrothermally Synthesized Mesoporous Silicates In Acetic Acid Esterification, Veli̇ Şi̇mşek, Levent Deği̇rmenci̇, Kirali̇ Mürtezaoğlu
Turkish Journal of Chemistry
A hydrothermal method was applied in the synthesis of mesoporous silicates containing silicotungstic acid (STA). The synthesis procedures were developed by modification of procedures previously applied in the synthesis of MCM-41 and SBA-15. The synthesized catalysts were named MCM-41-S and SBA-15-S based on MCM-41 and SBA-15. Their activities were investigated in ethyl acetate production, which was selected as the model reaction. The results indicated that the activity of SBA-15-S catalysts increased with increasing STA in the catalyst. Reaction experiments were also conducted in identical conditions in the presence of catalysts recovered after the reaction. The results indicated that sustainable activity …