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Articles 1231 - 1260 of 2628
Full-Text Articles in Physical Sciences and Mathematics
Synthesis And Characterization Of Tetra-Substituted Titanium(Iv) Phthalocyanines With Axial Ligand, Deni̇z Kutlu Tarakci, İlke Gürol
Synthesis And Characterization Of Tetra-Substituted Titanium(Iv) Phthalocyanines With Axial Ligand, Deni̇z Kutlu Tarakci, İlke Gürol
Turkish Journal of Chemistry
In this paper, the synthesis and characterization of peripheral tetra-2-(2-ethyloxyethyloxy)ethyloxy substituted oxo-titanium phthalocyanines (TiOPcs) are reported. The reaction of 2,2,3,3-tetrafluoropropoxy substituted and [2-(2-ethoxyethoxy)ethoxy] substituted TiOPcs (1 and 3) with 4-[(6-hydroxyhexyl)oxy]benzene-1,2-diol as a strongly chelating oxygen donor ligand is described. Compounds 1a and 3a bearing the hydroxyl group as an axial ligand of the bulky group are converted into a thiol group (1c and 3c). The new compounds are characterized by elemental analysis, FT-IR, ^1H NMR, and mass spectrometry. While the fluoropropoxy substituted TiOPc has good solubility in polar solvents such as acetone and THF, the other TiOPc is soluble in …
Synthesis And Electrochemical And Spectroelectrochemical Characterization Of Chloromanganese(Iii) Phthalocyanines, Mukaddes Özçeşmeci̇, Ilgin Nar, Esi̇n Hamuryudan
Synthesis And Electrochemical And Spectroelectrochemical Characterization Of Chloromanganese(Iii) Phthalocyanines, Mukaddes Özçeşmeci̇, Ilgin Nar, Esi̇n Hamuryudan
Turkish Journal of Chemistry
The synthesis of novel, symmetrical, tetrasubstituted manganese phthalocyanine complexes bearing 4 hexylthio, 2',3',4',5',6'-pentafluorobenzyloxy, 2',3',5',6'-tetrafluoro-4'-hexylthio-benzyloxy, and 2',3',5',6'-tetrafluoro-4'-pentoxy-benzyloxy units is reported. The new compounds have been characterized by using elemental analyses and UV-Vis, FT-IR, and mass spectroscopic data. The electrochemical properties of the manganese phthalocyanine complexes were investigated by cyclic and square wave voltammetry and the nature of the observed redox processes was studied by spectroelectrochemistry.
Diphenylethoxy-Substituted Metal-Free And Metallophthalocyanines As Potential Photosensitizer For Photodynamic Therapy: Synthesis And Photophysical And Photochemical Properties, Yusuf Yilmaz, Ali̇ Erdoğmuş, Muhammet Kasim Şener
Diphenylethoxy-Substituted Metal-Free And Metallophthalocyanines As Potential Photosensitizer For Photodynamic Therapy: Synthesis And Photophysical And Photochemical Properties, Yusuf Yilmaz, Ali̇ Erdoğmuş, Muhammet Kasim Şener
Turkish Journal of Chemistry
The synthesis of a 4-(2,2-diphenylethoxy)phthalonitrile (1) and its organosoluble free base (2), zinc(II) (3), nickel(II) (4), and cobalt(II) (5) phthalocyanine derivatives is presented in this work. The novel complexes were characterized by elemental analyses and spectral data such as infrared, nuclear magnetic resonance, ultraviolet visible, and mass data. General tendencies were described for photophysics (fluorescence) and photochemistry (photodegradation and singlet oxygen quantum yields) of the free base and zinc(II) phthalocyanine derivatives in dimethylformamide. The quantum yield values of fluorescence (\Phi_F), singlet oxygen formation (\Phi_{\Delta}), and photodegradation (\Phi_d) for the zinc phthalocyanine were found to be 0.37, 0.48, and 9.12 \times …
Synthesis, Characterization, And Photophysical And Photochemical Properties Of 3-(4-Phenyloxy)Coumarin Containing Metallo- And Metal-Free Phthalocyanines, Nurullah Kartaloğlu, Ali̇ye Asli Esenpinar, Mustafa Bulut
Synthesis, Characterization, And Photophysical And Photochemical Properties Of 3-(4-Phenyloxy)Coumarin Containing Metallo- And Metal-Free Phthalocyanines, Nurullah Kartaloğlu, Ali̇ye Asli Esenpinar, Mustafa Bulut
Turkish Journal of Chemistry
The synthesis of novel zinc, cobalt, indium, and metal-free phthalocyanines carrying four 3-(4-phenyloxy)couma- rins in the periphery/nonperiphery were prepared by cyclotetramerization of 3-[4-(3,4-dicyanophenyloxy)phenyl]coumarin (2)/3-[4-(2,3- dicyanophenyloxy)phenyl]coumarin (3). The novel chromogenic compounds were characterized by elemental analysis, ^1H NMR, mass spectra, F-IR, and UV-vis spectral data. The effects of the coumarin units on the zinc, indium, and metal-free phthalocyanine complexes (2a/3a, 2c/3c, 2d/3d) were also investigated.
Synthesis And Properties Of Novel Polymeric Metal-Free And Metallophthalocyanines Containing Peripherally Long 1,2-Bis[(3-Oxapropyl)Oxa]Benzene Derivatives, Ahmet Bi̇lgi̇n, Durmuş Yanmaz, Çi̇ğdem Yağci
Synthesis And Properties Of Novel Polymeric Metal-Free And Metallophthalocyanines Containing Peripherally Long 1,2-Bis[(3-Oxapropyl)Oxa]Benzene Derivatives, Ahmet Bi̇lgi̇n, Durmuş Yanmaz, Çi̇ğdem Yağci
Turkish Journal of Chemistry
New polymeric phthalocyanine moieties (M = 2H, Zn, Ni, Cu, and Co) were synthesized via polytetracyclomerization reaction of o-bis[3-(3,4-dicyanophenoxy)propyloxy]benzene (3), which can be obtained by the reaction of 4-nitrophthalonitrile with o-bis[(3-hydroxypropyl)oxy]benzene. Aggregation and disaggregation behavior of the polymeric phthalocyanine (5) was studied with some alkali and earth alkali metal cations. Measured intrinsic viscosities of the polymeric phthalocyanines exhibited a substantial decreasing tendency with dilution of the solution. Thermogravimetric analysis was performed under air by using DSC and DTG/TGA techniques and indicated that these polymers have good thermal stability. AC and DC electrical conductivities of the polymeric phthalocyanines were investigated in …
Microwave-Assisted Synthesis And Characterization Of Co(Ii) Phthalocyanine And Investigation Of Its Catalytic Activity On 4-Nitrophenol Oxidation, Ece Tuğba Saka, Zekeri̇ya Biyiklioğlu, Hali̇t Kanteki̇n
Microwave-Assisted Synthesis And Characterization Of Co(Ii) Phthalocyanine And Investigation Of Its Catalytic Activity On 4-Nitrophenol Oxidation, Ece Tuğba Saka, Zekeri̇ya Biyiklioğlu, Hali̇t Kanteki̇n
Turkish Journal of Chemistry
In this study, new cobalt phthalocyanine containing a 2-(2-benzothiazolylthio)ethoxy group at peripheral positions has been synthesized and characterized by spectroscopic methods (IR, UV-Vis elemental analysis, and mass spectroscopies). Catalytic activity of Co(II) phthalocyanine has been investigated in the presence of oxidants such as tert-buthylhydroperoxide, m-chloroperoxybenzoic acid, and H_2O_2. Co(II) phthalocyanine shows catalytically activity and product conversion under mild conditions. To find the optimal conditions in the oxidation process, substrate ratio, oxidant ratio, temperature, and oxidant type were examined over 3 h. The results exhibit the best optimum reaction conditions in this catalytic system.
New Soluble Amidoamine Substituted Phthalocyanines: Synthesis, Characterization, And Investigation Of Their Solution Properties, Senem Çolak, Sali̇h Zeki̇ Yildiz
New Soluble Amidoamine Substituted Phthalocyanines: Synthesis, Characterization, And Investigation Of Their Solution Properties, Senem Çolak, Sali̇h Zeki̇ Yildiz
Turkish Journal of Chemistry
The synthesis of tetraaminopropylamid substituted phthalocyanines was targeted to prepare enhanced soluble phthalocyanines in common solvents from hydrophobic to hydrophilic that bore nonionic groups on their periphery. Metal-free (H_2Pc) and metallophthalocyanines (Zn(II) (ZnPc), Cu(II) (CuPc) and Co(II) (CoPc)) were prepared and characterized by UV-Vis, FT-IR, and mass spectroscopies. The ^1H NMR spectra were recorded for the diamagnetic phthalocyanine species H_2Pc and ZnPc. The phthalocyanines showed sufficient solubility in common organic solvents such as dimethyl sulfoxide, tetrahydrofuran, and ethanol. However, methanol was not a good solvent for CuPc and H_2Pc. Solubility and aggregation studies of H_2Pc and ZnPc were performed in …
Microwave-Assisted Synthesis Of Novel Nonperipherally Substituted Metallophthalocyanines Bearing (7-(Trifluoromethyl)Quinolin-4-Yl)Oxy Groups, Di̇dem Evren, Hacer Yasemi̇n Yeni̇lmez, Ayfer Kalkan Burat
Microwave-Assisted Synthesis Of Novel Nonperipherally Substituted Metallophthalocyanines Bearing (7-(Trifluoromethyl)Quinolin-4-Yl)Oxy Groups, Di̇dem Evren, Hacer Yasemi̇n Yeni̇lmez, Ayfer Kalkan Burat
Turkish Journal of Chemistry
The synthesis, characterization, and spectroscopic properties of novel nonperipherally tetrasubstituted metallophthalocyanines (zinc, cobalt, copper, manganese, and indium) bearing 4 (7-(trifluoromethyl)quinolin-4-yl)oxy units has been reported. The new compounds have been characterized using UV-Vis, IR, ^1H NMR, ^{13}C NMR, ^{19}F NMR, and mass spectroscopic data. The absorption properties of these new complexes were compared to those of peripherally substituted phthalocyanine derivatives. Based on the structural, spectroscopic, and absorption studies, it was found that the substitution effect altered the electronic structures significantly. The results provide useful information to understand the effect of peripheral or nonperipheral substitution on the properties of this macrocyclic ring. …
Water-Soluble Phthalocyanines Containing Azo Dye; Microwave-Assisted Synthesis And Photochemical Properties Of Znpcs, Ci̇han Kantar, Emrah Ataci, Selami̇ Şaşmaz
Water-Soluble Phthalocyanines Containing Azo Dye; Microwave-Assisted Synthesis And Photochemical Properties Of Znpcs, Ci̇han Kantar, Emrah Ataci, Selami̇ Şaşmaz
Turkish Journal of Chemistry
Novel water-soluble metallophthalocyanines (M: Co, Ni, Cu, Zn) containing azo dye were characterized. The structures were confirmed by IR, UV/vis, ^1H NMR, ^{13}C NMR, mass spectroscopy, and elemental analysis. Photochemical properties and aggregation behavior of zinc phthalocyanines were investigated. Singlet oxygen quantum yields of the zinc phthalocyanines (2d, 3d, 5d, and 6d) were 0.8, 0.57, 0.71, and 0.46, respectively.
Immobilized Metal Ion Affinity Nanospheres For \Alpha-Amylase Immobilization, Tülden Kalburcu, Müni̇re Nalan Tüzmen, Si̇nan Akgöl, Adi̇l Deni̇zli̇
Immobilized Metal Ion Affinity Nanospheres For \Alpha-Amylase Immobilization, Tülden Kalburcu, Müni̇re Nalan Tüzmen, Si̇nan Akgöl, Adi̇l Deni̇zli̇
Turkish Journal of Chemistry
Immobilized metal chelate affinity chromatography (IMAC) support was practiced for \alpha-amylase immobilization. Poly(hydroxyethylmethacrylate-methacryloylamidotryptophan)-Ni^{2+} [p(HEMA-MAT)-Ni^{2+}] nanospheres, average diameter 100 nm, were produced by surfactant free emulsion polymerization. Characterizations of p(HEMA-MAT)-Ni^{2+} nanospheres were carried out by Fourier transform infrared (FTIR) spectroscopy and scanning electron microscope (SEM). In addition, average particle size, size distribution, and surface charge were specified. The amount of N-methacryloylamidotryptophan (MAT) incorporated to polymer was determined as 1.95 mmol/g polymers by using nitrogen stoichiometry. The specific surface areas of poly(hydroxyethylmethacrylate) [p(HEMA)] and p(HEMA-MAT) nanospheres were calculated as 1856 m^2/g and 1914 m^2/g, respectively. Protein adsorption increased with increasing initial protein …
Economic Synthesis Of Quinaldinium Fluorochromate(Vi), (Qnfc), And Solvent-Free Periodic Acid Oxidation Of Alcohols Catalyzed By Qnfc, Melek Özdemi̇r, Hati̇ce Beyti̇ye Özgün
Economic Synthesis Of Quinaldinium Fluorochromate(Vi), (Qnfc), And Solvent-Free Periodic Acid Oxidation Of Alcohols Catalyzed By Qnfc, Melek Özdemi̇r, Hati̇ce Beyti̇ye Özgün
Turkish Journal of Chemistry
A 1:1:1 stoichiometric reaction between CrO_3, aqueous HF, and quinaldine affords orange crystalline quinaldinium fluorochromate(VI) (QnFC) (C_{10}H_9NH[CrO_3F]) in 99.4% isolated yield. A highly efficient, simple, chemoselective, and environmentally benign procedure for QnFC (3 mol%) catalyzed oxidation of primary and secondary alcohols to aldehydes and ketones using 1.1 equiv of H_5IO_6 under solvent-free conditions is described.
Synthesis, Structure, And Luminescent Properties Of 2 Novel 5-Chlorhydroxybenzoate-Imidazole Metal-Organic Complexes, Hong Chen, Si Yuan Luo, Xiuling Wu, Yongqian Wang, Bo Hu, Chao Hu, Gang Huang, Qiao Xin Du
Synthesis, Structure, And Luminescent Properties Of 2 Novel 5-Chlorhydroxybenzoate-Imidazole Metal-Organic Complexes, Hong Chen, Si Yuan Luo, Xiuling Wu, Yongqian Wang, Bo Hu, Chao Hu, Gang Huang, Qiao Xin Du
Turkish Journal of Chemistry
Two novel Zn and Cu complexes with 5-chlorhydroxybenzoate and imidazole ligands, C_{41}H_{36}Zn_2N_8O_{13}Cl_4 (1) and C_{26}H_{22}Cl_2Cu_2N_8O_6 (2), were prepared by slow evaporation method. Single crystal X-ray diffraction analysis was used to determine their structures. The purity of the complexes was confirmed by powder X-ray diffraction analysis. In 1 the Zn^{2+} cation is tetracoordinated with 2 nitrogen atoms from 2 imidazoles and 2 oxygen atoms from the 2 carboxyl groups in 5-chlorhydroxybenzoate. In 2 the coordination polyhedrons of Cu^{2+} center can be described as distorted square pyramidal geometry sharing common edges, with an oxygen atom on the top of the pyramid. The …
A Combined First Principles Tddft And Experimental Study On The Uv-Vis Spectra Properties Of M(P-Nitrophenyl Azo Resorcinol)_3 Complexes (M: Fe, Cr), Tuğba Ari̇fi̇oğlu, Meli̇s Efeçinar, Nuray Şatiroğlu
A Combined First Principles Tddft And Experimental Study On The Uv-Vis Spectra Properties Of M(P-Nitrophenyl Azo Resorcinol)_3 Complexes (M: Fe, Cr), Tuğba Ari̇fi̇oğlu, Meli̇s Efeçinar, Nuray Şatiroğlu
Turkish Journal of Chemistry
UV-Vis absorption data of p-nitrophenyl azo resorcinol (Magneson I) and its 2 Fe(III) and Cr(III) complexes were investigated both experimentally and theoretically. The geometries were optimized at BP86/TZVP level. The most stable spin states were computed as doublet and quartet for Fe(magneson)_3 and Cr(magneson)_3 complexes, respectively. Time-dependent density functional theory (TDDFT) was employed to explore the absorption spectra properties, whereas the solvent effects were taken into account using the polarizable continuum model (PCM). The M06, B3LYP, and PBE0 hybrid functionals together with TZVP/LANL2TZ basis sets were used for comparing the results with experimental data. The theoretical analysis of electronic structure …
Comparison Of Chelating Ability Of No-, Ns-, Ons-, And Ono-Type Schiff Base Derivatives And Their Stability Constants Of Bis-Complexes With Copper(Ii), Hasan Atabey, Esra Findik, Hayati̇ Sari, Mustafa Ceylan
Comparison Of Chelating Ability Of No-, Ns-, Ons-, And Ono-Type Schiff Base Derivatives And Their Stability Constants Of Bis-Complexes With Copper(Ii), Hasan Atabey, Esra Findik, Hayati̇ Sari, Mustafa Ceylan
Turkish Journal of Chemistry
The present study includes important findings relating to the number of donor atoms, species of ligands, and stabilities of complexes. Stabilities of complexes between Cu(II) ion and NO-, NS-, ONS-, and ONO-type Schiff bases were compared. Acid-base properties of the Schiff bases were explained at 25 \pm 0.1 °C and ionic strength (I) of 0.1 M supported by NaCl. The Hyperquad computer program was used for calculation of dissociation and stability constants. The overall stability constants of their Cu(II) complexes were calculated and the various formed complexes between the Schiff bases with Cu(II) ion formulated as CuL_2, CuHL_2, CuH_2L_2, and …
On The Peculiar Reactivity Of A C,N-Annelated Isoindole Core, Iaroslav Baglai, Valerie Maraval, Zoia Vsevolodivna Voitenko, Carine Duhayon, Yulian Mihailovich Volovenko, Remi Chauvin
On The Peculiar Reactivity Of A C,N-Annelated Isoindole Core, Iaroslav Baglai, Valerie Maraval, Zoia Vsevolodivna Voitenko, Carine Duhayon, Yulian Mihailovich Volovenko, Remi Chauvin
Turkish Journal of Chemistry
C-, N-, and/or O-methylation products were generated from 11H-isoindolo[2,1-a]quinazoline-5-one upon treatment with NaH followed by iodomethane under air, and possible recrystallization from methanol. Two products were fully characterized by NMR and X-ray diffraction analysis. In accordance with the HSAB principle, this soft methylating agent (MeI) leads mainly to the C,C-dimethylated product 11,11-dimethyl-11H-isoindolo[2,1-a]quinazoline-5-one, which was previously not observed, beside the N-methylated product, in a procedure using methyl tosylate as a hard methylating agent of the same substrate in the initial absence of a base. A mechanism is finally proposed for the formation of methyl 2-(3-methyl-4-oxo-3,4-dihydroquinazolin-2-yl)benzoate as an oxidation side product.
Simulation Of Impedance Spectra Of Oxalic Acid Electroreduction To Glyoxylic Acid: Effect Of Chemical Activator, Ph, Activation Energy, And Reduction Potential, Ni̇yazi̇ Alper Tapan
Simulation Of Impedance Spectra Of Oxalic Acid Electroreduction To Glyoxylic Acid: Effect Of Chemical Activator, Ph, Activation Energy, And Reduction Potential, Ni̇yazi̇ Alper Tapan
Turkish Journal of Chemistry
The aim of this study was to examine qualitatively the effect of important electrochemical parameters on the faradaic impedance spectra of oxalic acid electroreduction. The impedance spectrum of a 3-step oxalic acid electroreduction mechanism was simulated by the solution of a faradaic impedance equation based on 3 state variables. Before the solution of the faradaic impedance equation, the electroreduction mechanism was analyzed and it was seen that this mechanism can be represented by an electrical circuit composed of 2 resistors and a capacitance or inductance. The effect of chemical activator on the impedance spectrum was determined by using the relation …
Experimental Investigation Of Drag Reduction Effects Of Polymer Additives On Turbulent Pipe Flow Using Ultrasound Doppler Velocimetry, Şeri̇fe Zeybek Vural, Göknur Bayram, Yusuf Uludağ
Experimental Investigation Of Drag Reduction Effects Of Polymer Additives On Turbulent Pipe Flow Using Ultrasound Doppler Velocimetry, Şeri̇fe Zeybek Vural, Göknur Bayram, Yusuf Uludağ
Turkish Journal of Chemistry
Drag reduction in fully developed turbulent pipe flow with 4 concentrations (200 to 500 wppm or mg/kg) of low molecular weight sodium carboxymethylcellulose (CMC) in aqueous solutions was investigated experimentally. Drag reduction was determined by pressure drop measurements. Maximum drag reduction achieved was 22% using 500 wppm CMC solution. To observe the impact of the presence of CMC on the flow, ultrasound Doppler velocimetry (UDV) was employed to monitor the instantaneous velocity distributions. Experimental measurements were used to calculate Fanning friction factor and radial distributions of the axial time-averaged velocity, velocity fluctuation (turbulent intensity), and eddy viscosity. Two impacts of …
Synthesis And Antimicrobial Activity Of Novel 2-[4-(1h-Benzimidazol-1-Yl)Phenyl]-1h-Benzimidazoles, Mehmet Alp, Ali̇ Hakan Göker, Nurten Altanlar
Synthesis And Antimicrobial Activity Of Novel 2-[4-(1h-Benzimidazol-1-Yl)Phenyl]-1h-Benzimidazoles, Mehmet Alp, Ali̇ Hakan Göker, Nurten Altanlar
Turkish Journal of Chemistry
A new class of 2-[4-(1H-benzimidazol-1-yl)phenyl]-1H-benzimidazoles (13--22) were synthesized via cyclocondensation reaction of the substituted 1,2-phenylenediamines (1, 4--12) and 1-(4-formylpheny)-1H-benzimidazole (3). The synthesized compounds were evaluated for antibacterial and antifungal activities against S. aureus, methicillin-resistant Staphylococcus aureus (MRSA), and Candida albicans by the tube dilution method. Compounds 13, 15, 18, 20, and 21 have moderate antifungal activity against C. albicans.
Preparation Of A Novel Solid Acid Catalyst With Lewis And Brønsted Acid Sites And Its Application In Acetalization, Yijun Du, Linjun Shao, Lingyan Luo, Si Shi, Chenze Qi
Preparation Of A Novel Solid Acid Catalyst With Lewis And Brønsted Acid Sites And Its Application In Acetalization, Yijun Du, Linjun Shao, Lingyan Luo, Si Shi, Chenze Qi
Turkish Journal of Chemistry
A novel melamine--formaldehyde resin (MFR) supported solid acid with Lewis and Brønsted acid sites was synthesized through the immobilization of acidic ionic liquid and cuprous ion on MFR. The scanning electron microscopy (SEM) characterization showed that addition of PEG-2000 in the synthesis of MFR could promote the formation of regular particles with diameters around 3.7 \mu m. The XRD pattern demonstrated that some cuprous ions were aggregated. The catalytic performance of this acid catalyst was evaluated by acetalization. The results showed that the catalytic activity of MFR with Brønsted acid could be improved by addition of Lewis acid. The solid …
Self-Condensation Reactions Of Acyl Phosphonates: Synthesis Of Tertiary O-Protected \Alpha-Hydroxyphosphonates, Serkan Eymur, Mehmet Göllü, Ayhan Sitki Demi̇r
Self-Condensation Reactions Of Acyl Phosphonates: Synthesis Of Tertiary O-Protected \Alpha-Hydroxyphosphonates, Serkan Eymur, Mehmet Göllü, Ayhan Sitki Demi̇r
Turkish Journal of Chemistry
The self-condensation reaction of benzoyl dialkyl phosphonates was developed using cyanide ion as catalyst, affording versatile tertiary O-protected \alpha-hydroxy phosphonates in moderate yield.
Speciation Of Chromium By The Combination Of Dispersive Liquid--Liquid Microextraction And Microsample Injection Flame Atomic Absorption Spectrometry, Yunusemre Ünsal, Mustafa Tüzen, Mustafa Soylak
Speciation Of Chromium By The Combination Of Dispersive Liquid--Liquid Microextraction And Microsample Injection Flame Atomic Absorption Spectrometry, Yunusemre Ünsal, Mustafa Tüzen, Mustafa Soylak
Turkish Journal of Chemistry
A microextraction procedure was established for the speciation of total Cr, Cr(III), and Cr(VI). Sudan blue II was used as a ligand for speciation works. Some factors affecting the recoveries of chromium species, including type of extraction and dispersive solvents, pH, ligand amount, extraction time, and matrix ions, were examined. Optimum values for the dispersive liquid--liquid microextraction method were pH 6, LOD 0.34 \mu g L^{-1}, and preconcentration factor 400. Chromium(III) was quantitatively recovered under optimal conditions, while the recovery of chromium(VI) was below 10%. The relative standard deviation for Cr(III) determinations for the 10-replicate measurement of 0.3 \mu g …
Preparation Of A Lead Sensor Based On Porous Multiwalled Carbon Nanotubes/Thiolated Chitosan Composite Materials, Jun Wan, Ling Xing, Wei Wang
Preparation Of A Lead Sensor Based On Porous Multiwalled Carbon Nanotubes/Thiolated Chitosan Composite Materials, Jun Wan, Ling Xing, Wei Wang
Turkish Journal of Chemistry
Thiolated chitosan (CS--TGA) was prepared using chitosan (CS) and thioglycolic acid (TGA). Then MWCNTs were added to the mixture of CS--TGA and CS to prepare the CS/CS--TGA/MWCNs porous composite by freeze-drying method and this composite was used to modify an indium tin oxide glass electrode. The electrode was used as a sensor for Pb^{2+}. The morphology and structure of the composite were characterized by infrared spectroscopy and scanning electron microscope, and their electrochemical behavior was also studied. Under the optimized experimental conditions, the sensor showed a linear range of 2.0 \times 10^{-9}\sim 2.0 \times 10^{-8} mol L^{-1} for Pb^{2+} with …
Synthesis And X-Ray Powder Diffraction, Electrochemical, And Genotoxic Properties Of A New Azo-Schiff Base And Its Metal Complexes, Mustafa Bal, Gökhan Ceyhan, Bariş Avar, Muhammet Köse, Ahmet Kayraldiz, Mükerrem Kurtoğlu
Synthesis And X-Ray Powder Diffraction, Electrochemical, And Genotoxic Properties Of A New Azo-Schiff Base And Its Metal Complexes, Mustafa Bal, Gökhan Ceyhan, Bariş Avar, Muhammet Köse, Ahmet Kayraldiz, Mükerrem Kurtoğlu
Turkish Journal of Chemistry
A new, substituted 2-[(E)-{[4-(benzyloxy)phenyl]imino} methyl]-4-[(E)-(4-nitrophenyl)diazenyl]phenol azo-azomethine ligand (mbH) was synthesized from 2-hydroxy-5-[(4-nitrophenyl)diazenyl]benzaldehyde and 4-benzyloxyanilinehydrochloride in ethyl alcohol solution. These mononuclear Mn(II), Co(II), Ni(II), Cu(II), and Zn(II) complexes of the ligand were prepared and their structures were proposed by elemental analysis, and infrared and ultraviolet-visible spectroscopy; the proton NMR spectrum of the mbH ligand was also recorded. The azo-azomethine ligand, mbH, behaves as a bidentate ligand coordinating through the nitrogen atom of the azomethine (--CH=N--) and the oxygen atom of the phenolic group. Elemental analyses indicated that the metal:ligand ratio was 1:2 in the metal chelates. Powder X-ray diffraction parameters suggested …
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.
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
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 …
Effect Of Boric Acid On Corrosion And Electrochemical Performance Of Pb-0.08% Ca-1.1% Sn Alloys Containing Cu, As, And Sb Impurities For Manufacture Of Grids Of Lead-Acid Batteries, Said Salih, Ahmed Gad-Allah, Ashraf Abd El-Wahab, Hamid Abd Elrahman
Effect Of Boric Acid On Corrosion And Electrochemical Performance Of Pb-0.08% Ca-1.1% Sn Alloys Containing Cu, As, And Sb Impurities For Manufacture Of Grids Of Lead-Acid Batteries, Said Salih, Ahmed Gad-Allah, Ashraf Abd El-Wahab, Hamid Abd Elrahman
Turkish Journal of Chemistry
The electrochemical performance of lead-acid batteries made of Pb--Ca--Sn alloys with and without 0.1% of each of Cu, As, and Sb individually and combined in 4.0 M H_2SO_4 in the absence and presence of 0.4 M H_3BO_3 was studied. Both impurities and H_3BO_3 were found to reduce the corrosion rate. Cyclic voltammetry revealed that the presence of impurities or H_3BO_3 significantly retarded the formation of large crystal PbSO_4. H_3BO_3 increased the rates of oxygen and hydrogen evolution reactions for all alloys. Impedance measurement was used to quantify the amounts of PbSO_4 and PbO in the initial stage of the oxidation. …
Synthesis And Characterization Of New (E)-N'-(Substituted Benzylidene)-2-(3-(2-Methyl)-4-Oxo-3,4-Dihydroquinazolin-2-Ylthio)Acetohydrazides, Aamer Saeed, Shams-Ul Mahmood, Ulrich Flörke
Synthesis And Characterization Of New (E)-N'-(Substituted Benzylidene)-2-(3-(2-Methyl)-4-Oxo-3,4-Dihydroquinazolin-2-Ylthio)Acetohydrazides, Aamer Saeed, Shams-Ul Mahmood, Ulrich Flörke
Turkish Journal of Chemistry
A small library of new azomethine derivatives of 3-aryl-2-thioxo-2,3-dihydroquinazolin-4(1H)-ones was synthesized. The key intermediates 2-thioxo-quinazolinones (3a--e), obtained in 2 steps from the corresponding anilines, were treated with methyl chloroacetate to afford S-substituted esters (4a,d), which were then converted into corresponding acetohydrazides (5a,d). Further, acetohydrazide (5d) was converted to the azomethines derivatives (6a--k) by reacting with a number of suitably substituted benzaldehydes. FTIR, ^1H NMR, ^{13}C NMR, GC-MS, and elemental analyses were used to confirm the assigned structures of the synthesized compounds. Further, compounds 3a, 5, and 6j were also confirmed by X-ray diffraction data.
Calixpenams: Synthesis, Characterization, And Biological Evaluation Of Penicillins V And X Clustered By Calixarene Scaffold, Fazel Nasuhi Pur, Karim Akbari Dilmaghani
Calixpenams: Synthesis, Characterization, And Biological Evaluation Of Penicillins V And X Clustered By Calixarene Scaffold, Fazel Nasuhi Pur, Karim Akbari Dilmaghani
Turkish Journal of Chemistry
Four 6-aminopenicillanic acid moieties were grafted at either rim of calix[4]arene, giving 2 novel generations of penicillin, which were named calixpenam. Antibiotic tests showed that they have amplified activity with respect to the corresponding penams against 3 gram-positive nonpenicillinase-producing strains of Streptococcus.
Optimization Of Lifepo_4 Synthesis By Hydrothermal Method, Muhsi̇n Mazman, Ömür Çuhadar, Davut Uzun, Ercan Avci, Emre Bi̇çer, Tevhi̇t Cem Kaypmaz, Ümüt Kadi̇roğlu
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 …
Platinum Or Nickel Nanoparticles Decorated On Silica Spheres By Microwave Irradiation Technique, Ayşe Bayrakçeken
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.