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Articles 13201 - 13230 of 14008
Full-Text Articles in Entire DC Network
Antioxidant Galloylated Flavonoids From Geranium Tuberosum L. Subsp. Tuberosum, Di̇dem Şöhretoğlu, Mahmut Koray Sakar, Suna Atasayar Sabuncuoğlu, Hi̇lal Özgüneş, Olov Sterner
Antioxidant Galloylated Flavonoids From Geranium Tuberosum L. Subsp. Tuberosum, Di̇dem Şöhretoğlu, Mahmut Koray Sakar, Suna Atasayar Sabuncuoğlu, Hi̇lal Özgüneş, Olov Sterner
Turkish Journal of Chemistry
Phytochemical investigations on the most active EtOAc extract led to the isolation of 9 flavonoids [quercetin (1), quercetin 3-O-\beta-glucopyranoside (2), quercetin 3-O-\beta-galactopyranoside (3), quercetin 3-O-(2''-O-galloyl)-\beta-glucopyranoside (4), quercetin 3-O-(2''-O-galloyl)-\beta-galactopyranoside (5), quercetin 3-O-(6''-O-galloyl)-\beta-glucopyranoside (6), quercetin 3-O-(6''-O-galloyl)-\beta-galactopyranoside (7), quercetin-3-O-\alpha -arabinofuranoside (8), and quercetin-3-O-\alpha-rhamnopyranosyl-(1\to 6)-\beta-glucopyranoside (9)] and a simple phenolic compound (methyl gallate) (10). The structures of the compounds were elucidated by 1- and 2-dimensional NMR techniques (^1H, ^{13}C, COSY, HMBC, and HMQC) and ESI-TOF-MS spectrometry. H_2O_2-induced lipid peroxidation inhibitor effects in human red blood cells of different extracts of G. tuberosum L. subsp. tuberosum aerial parts were also investigated. All the compounds tested …
A Systematic Study On The Absorption And Fluorescence Properties Of 2,4,6-Triaryl And Tripyridylpyridines, Esra Findik, Mustafa Arik, Mustafa Ceylan
A Systematic Study On The Absorption And Fluorescence Properties Of 2,4,6-Triaryl And Tripyridylpyridines, Esra Findik, Mustafa Arik, Mustafa Ceylan
Turkish Journal of Chemistry
Eight different 2,4,6-triaryl, and tripyridylpridines compounds were synthesized and their fluorescent properties were studied by using steady-state and time-resolved fluorescence and UV-Vis absorption spectroscopy techniques in 6 different solvents. Especially, 2,4,6-triarylpyridines showed strong fluorescence properties with high fluorescence quantum yields but small Stokes shifts.
Reactions Of The Solvent-Stabilized Compound [Moocl_2(Thf)_2] With Aromatic Nitrogen Donor Ligands: Spectroscopic Characterization And Semiempirical Am1* Calculations, Gülşah Kiliçkaya, Başak Doğan, Nursel Acar, Işil Topaloğlu Sözüer
Reactions Of The Solvent-Stabilized Compound [Moocl_2(Thf)_2] With Aromatic Nitrogen Donor Ligands: Spectroscopic Characterization And Semiempirical Am1* Calculations, Gülşah Kiliçkaya, Başak Doğan, Nursel Acar, Işil Topaloğlu Sözüer
Turkish Journal of Chemistry
Reaction of the solvent-stabilized dioxo-molybdenum(VI) compound [MoO_2Cl_2(THF)_2] with PPh_3 yielded the oxomolybdenum(IV) species [MoOCl_2(THF)_2] (1) by the removal of one oxygen atom as PPh_3O. The complexes [MoOCl_2(=NC_6H_4CN)] 2, [MoOCl_2(CNC_6H_4OH)] 3, [MoOCl_2(=NC_6H_4NH_2)] 4, and [MoOCl_2(=NC_6H_4OCH_3)] 5, were synthesized by the reactions of [MoOCl_2(THF)_2] with XC_6H_4Y (X = NH_2, Y = CN; X= CN, Y = OH; X = Y = NH_2; X = NH_2, Y = OCH_3). All the new compounds were characterized by elemental analyses, and FTIR, UV-Vis, and ^1H- and ^{13}C-NMR spectra. Geometrical parameters and molecular orbital calculations showed that compounds 2-5 are stabilized by a charge transfer between …
Comparative Study Of Selective Co Oxidation Over Pt-Co-M/Al_2o_3 Catalysts (M=Ce, Mg, Mn, Zr, Fe) In Hydrogen-Rich Streams: Effects Of A Second Promoter, K. Erdem Uğuz, Ramazan Yildirim
Comparative Study Of Selective Co Oxidation Over Pt-Co-M/Al_2o_3 Catalysts (M=Ce, Mg, Mn, Zr, Fe) In Hydrogen-Rich Streams: Effects Of A Second Promoter, K. Erdem Uğuz, Ramazan Yildirim
Turkish Journal of Chemistry
The selective CO oxidation over Pt-Co/Al_2O_3 catalyst in hydrogen-rich streams was studied in the presence of Ce, Mg, Mn, Ze, and Fe as the second promoters. The catalysts were prepared using incipient to wetness co-impregnation, and tested in a microflow reaction system. The effects of the second promoter were investigated in near 100% CO conversion conditions both in the absence and presence of CO_2 and H_2O in the feed. 100% CO conversion was obtained with the addition of each second promoter at 110 °C while Pt-Co/Al_2O_3 catalyst had 96%-98% CO conversion. It was also found that changing the Pt ratio …
The Synthesis, Characterization And Energy Transfer Efficiency Of A Dithienylpyrrole And Bodipy Based Donor-Acceptor System, Taner Atalar, Ati̇lla Ci̇haner, Fati̇h Algi
The Synthesis, Characterization And Energy Transfer Efficiency Of A Dithienylpyrrole And Bodipy Based Donor-Acceptor System, Taner Atalar, Ati̇lla Ci̇haner, Fati̇h Algi
Turkish Journal of Chemistry
A dithienylpyrrole-BODIPY based donor-acceptor system with 1,4-phenylene spacer as a model system for energy transfer was designed and synthesized. Absorption and emission spectra have revealed an efficient resonance energy transfer from dithienylpyrrole as donor to BODIPY as acceptor.
Spectroscopic And Structural Study Of Ni(Ii) Dipicolinate Complex With 2-Amino-4-Methylpyrimidine, İclal Bulut, İbrahi̇m Uçar, Canan Kazak
Spectroscopic And Structural Study Of Ni(Ii) Dipicolinate Complex With 2-Amino-4-Methylpyrimidine, İclal Bulut, İbrahi̇m Uçar, Canan Kazak
Turkish Journal of Chemistry
Nickel(II) dipicolinate complex containing 2-amino-4- methylpyrimidine (2A-4Mpy), [Ni(2A-4Mpy)(dpc) (H_2O)_2] . 2H_2O was synthesized in solid state and its structural and spectroscopic properties were determined by XRD, IR, and UV-Vis techniques. The crystal data revealed that the Ni complex is in triclinic crystal systems with space group P-1 and Z = 2. The Ni(II) ion is bonded to dipicolinate ligand through pyridine N atom together with one O atom of each carboxylate group, 2 aqua ligands, and the N atom of 2-amino-4-methylpyrimidine, forming distorted octahedral geometry. IR and UV-Vis spectra of the complexes all agree with the observed crystal structure.
Synthesis, Characterization, And Antibacterial Effect Of 4-Methoxy-2-(5-H/Me/Cl/No_2-1h-Benzimidazol-2-Yl)- Phenols And Some Transition Metal Complexes, Aydin Tavman, Serkan İki̇z, Arzu Funda Bağcigi̇l, N. Yakut Özgür, Seyyal Ak
Synthesis, Characterization, And Antibacterial Effect Of 4-Methoxy-2-(5-H/Me/Cl/No_2-1h-Benzimidazol-2-Yl)- Phenols And Some Transition Metal Complexes, Aydin Tavman, Serkan İki̇z, Arzu Funda Bağcigi̇l, N. Yakut Özgür, Seyyal Ak
Turkish Journal of Chemistry
4-Methoxy-2-(5-H/methyl/chloro/nitro-1H-benzimidazol-2-yl)-phenol(HL_X; X=1-4) ligands and HL_1 complexes with Fe(NO_3)_3, Cu(NO_3)_2, AgNO_3, and Zn(NO_3)_2 were synthesized and characterized. The structures of the compounds were confirmed on the basis of elemental analysis, molar conductivity, magnetic moment, FT-IR, UV-visible, and ^1H- and ^{13}C-NMR. Antibacterial activity of the free ligands, their hydrochloride salts, and the complexes was evaluated using the disk diffusion method in dimethyl sulfoxide (DMSO) as well as the minimum inhibitory concentration (MIC) dilution method, against 9 bacteria, and the results were compared with penicillin-G and oxytetracycline. It was observed that HL_1, [Ag(HL_1)](NO_3), and [Cu(L_1)_2](H_2O)_2 are effective on S. epidermidis, S. aureus, and …
Methanol Dehydration Reaction To Produce Clean Diesel Alternative Dimethylether Over Mesoporous Aluminosilicate-Based Catalysts, Di̇lek Varişli, Kenan Cem Tokay, Ayşegül Çi̇ftçi̇, Ti̇mur Doğu, Gülsen Doğu
Methanol Dehydration Reaction To Produce Clean Diesel Alternative Dimethylether Over Mesoporous Aluminosilicate-Based Catalysts, Di̇lek Varişli, Kenan Cem Tokay, Ayşegül Çi̇ftçi̇, Ti̇mur Doğu, Gülsen Doğu
Turkish Journal of Chemistry
Due to its good burning characteristics and high cetane number, dimethylether (DME) is considered as a highly attractive and clean alternative to diesel fuel. This ether can be produced by methanol dehydration reaction over solid acid catalysts. In the present study, activities of mesoporous aluminosilicate catalysts prepared by the hydrothermal synthesis route and containing Al/Si atomic ratios ranging between 0.03 and 0.18 were tested in methanol dehydration. The optimum Al/Si ratio was 0.09 for DME synthesis. Activity of silicotungstic acid (STA) impregnated aluminosilicate was also tested. This STA impregnated catalyst showed very high DME yield values at temperatures as low …
Order Acceptance Using Genetic Algorithms, Walter O. Rom, Susan A. Slotnick
Order Acceptance Using Genetic Algorithms, Walter O. Rom, Susan A. Slotnick
Business Faculty Publications
This paper uses a genetic algorithm to solve the order-acceptance problem with tardiness penalties. We compare the performance of a myopic heuristic and a genetic algorithm, both of which do job acceptance and sequencing, using an upper bound based on an assignment relaxation. We conduct a pilot study, in which we determine the best settings for diversity operators (clone removal, mutation, immigration, population size) in connection with different types of local search. Using a probabilistic local search provides results that are almost as good as exhaustive local search, with much shorter processing times. Our main computational study shows that the …
Synthesis, Characterization, And Optical Properties Of Novel 2,5-Bis[4-(2-(-Arylvinyl)Phenyl]-1,3,4-Oxadiazoles, Dao-Hang He, Yong-Chuang Zhu, Zhuo-Ru Yang, Ai-Xi Hu, Gao Cao
Synthesis, Characterization, And Optical Properties Of Novel 2,5-Bis[4-(2-(-Arylvinyl)Phenyl]-1,3,4-Oxadiazoles, Dao-Hang He, Yong-Chuang Zhu, Zhuo-Ru Yang, Ai-Xi Hu, Gao Cao
Turkish Journal of Chemistry
Six novel 2,5-bis[4-(2-arylvinyl)phenyl]-1,3,4-oxadiazoles were synthesized by introducing 1,3,4-oxadiazole moiety into the stilbene skeleton. The synthesis route included the cyclization of p-toluic acid and hydrazine hydrate catalyzed by polyphosphoric acid (PPA), bromination of 1,3-dibromo-5,5-dimethylhydantoin (DBDMH), esterification, and the Wittig-Horner reaction. All the title compounds were characterized by ^1H-NMR, MS, and elemental analysis. UV-Vis absorption and fluorescence emission spectra in THF solution were investigated; the compounds may have potential for use in organic optical materials.
H_2{So}_4-Silica As An Efficient And Chemoselective Catalyst For The Synthesis Of Acylal From Aldehydes Under Solvent-Free Conditions, Seied Ali Pourmousavi, Zahra Zinati
H_2{So}_4-Silica As An Efficient And Chemoselective Catalyst For The Synthesis Of Acylal From Aldehydes Under Solvent-Free Conditions, Seied Ali Pourmousavi, Zahra Zinati
Turkish Journal of Chemistry
A variety of aldehydes react with acetic anhydride in the presence of a catalytic amount of H_2SO_4-silica to afford the corresponding 1,1-diacetates (acylals) in excellent yields. Ketones are not affected under the reaction conditions. The advantages are the simplicity of the acylation procedure, and the relatively non-toxic nature of the catalyst as well as its easy availability and low cost.
Synthesis, Reactions, And Antiarrhythmic Activities Of Some Novel Pyrimidines And Pyridines Fused With Thiophene Moiety, Abd El-Galil E. Amr, Naglaa A. Abdel-Hafez, Salwa F. Mohamed, Mohamed M. Abdalla
Synthesis, Reactions, And Antiarrhythmic Activities Of Some Novel Pyrimidines And Pyridines Fused With Thiophene Moiety, Abd El-Galil E. Amr, Naglaa A. Abdel-Hafez, Salwa F. Mohamed, Mohamed M. Abdalla
Turkish Journal of Chemistry
We report herein the synthesis and antiarrhythmic activities of some newly synthesized heterocyclic theino[2,3-c]pyrimidine and theino[2,3-c]pyridine derivatives fused with thiophene moiety. Initially the acute toxicity of the compounds was assayed via the determination of their LD_{50}. The antiarrhythmic activities for the compounds were determined and all the tested compounds were found more potent than Procaine amide^{\textregistered} and Lidocaine^{\textregistered} as positive antiarrhythmic controls.
Investigation Of The Fuel Properties Of Biodiesel Produced Over An Alumina-Based Solid Catalyst, Nezahat Boz, Mi̇ray Kara, Oylum Sunal, Ertan Alpteki̇n, Nebahat Deği̇rmenbaşi
Investigation Of The Fuel Properties Of Biodiesel Produced Over An Alumina-Based Solid Catalyst, Nezahat Boz, Mi̇ray Kara, Oylum Sunal, Ertan Alpteki̇n, Nebahat Deği̇rmenbaşi
Turkish Journal of Chemistry
The present study investigated the transesterification process used in the production of canola oil methyl ester from canola oil and methanol over synthesized KF/Al_2O_3 catalysts. Different amounts of KF solution (15-65 wt. %) were impregnated into alumina. Loading 35 wt. % of KF into an alumina (35% KF/Al_2O_3) catalyst gave the maximum yield of 99.6% under the following reaction conditions: 60 °C, 8-h reaction time, 15:1 molar ratio of methanol/canola oil, and 3 wt. % of catalyst. The fuel properties of canola oil methyl ester were tested, including ester content, density, viscosity, flash point, copper strip corrosion, total and free …
Characterization And Electrochemical Study Of Nano-Composition Based Methylene Blue- And Riboflavin-Nafion On The Surface Of Gold Electrode, Saeed Rezaei-Zarchi, Aisha Javed, Hossein Mirjalili, Hossain Bari Abarghouei, Seyed Ali Hashemizadeh
Characterization And Electrochemical Study Of Nano-Composition Based Methylene Blue- And Riboflavin-Nafion On The Surface Of Gold Electrode, Saeed Rezaei-Zarchi, Aisha Javed, Hossein Mirjalili, Hossain Bari Abarghouei, Seyed Ali Hashemizadeh
Turkish Journal of Chemistry
A functional membrane, composed of the nanoparticles of methylene blue (MB) and Nafion, was constructed during the present study. The materials were characterized by the methods of scanning electron microscopy (SEM), transmission electron microscopy (TEM), and UV-Visible and FT-IR. The average diameter of new nano-particles was estimated to be about 60 nm. A novel Nafion-riboflavin membrane was also constructed and characterized by the methods of SEM, TEM and UV-Visible spectroscopy. The estimated average diameter of the new nanoparticles was about 60 nm. The functional membranes of Nafion-riboflavin and Nafion-methylene blue showed a quasi-reversible electrochemical behavior, on the gold electrode, with …
Synthesis And In Vitro Anti-Helicobacter Pylori Activity Of 2-(Substituted Benzylthio)-5-(5-Nitro-2- Furyl)-1, 3, 4-Thiadiazole Derivatives, Negar Mohammadhosseini, Ali Asadipor, Bahram Letafat, Mohsen Vosooghi, Farideh Siavoshi, Abbas Shafiee, Alireza Foroumadi
Synthesis And In Vitro Anti-Helicobacter Pylori Activity Of 2-(Substituted Benzylthio)-5-(5-Nitro-2- Furyl)-1, 3, 4-Thiadiazole Derivatives, Negar Mohammadhosseini, Ali Asadipor, Bahram Letafat, Mohsen Vosooghi, Farideh Siavoshi, Abbas Shafiee, Alireza Foroumadi
Turkish Journal of Chemistry
Starting from (5-nitrofuran-2-yl)methylene diacetate, a new series of 2-[(substituted benzyl)thio]-5-(5-nitro-2-furyl)-1,3,4-thiadiazoles (6a-n) were synthesized and the structures of the compounds were determined using spectroscopic methods including mass spectrometry, ^1H-nuclear magnetic resonance, infrared spectroscopy, and elemental analysis. The in vitro anti-Helicobacter pylori activity of the synthesized compounds was evaluated by the disk diffusion method against the clinical isolates of Helicobacter pylori. The results indicated that most of the synthesized compounds exhibited significant inhibitory activity against H. pylori with respect to standard drug metronidazole. Compound 6l, containing the 2-chloro-6-fluorobenzylthio moiety, was the most potent compound tested.
Pregnane Steroids From The Heartwood Of Azadirachta Indica, Bina Shaheen Siddiqui, Syed Kashif Ali, Syed Tariq Ali, Fayyaz Ahmed
Pregnane Steroids From The Heartwood Of Azadirachta Indica, Bina Shaheen Siddiqui, Syed Kashif Ali, Syed Tariq Ali, Fayyaz Ahmed
Turkish Journal of Chemistry
The heartwood of Azadirachta indica (Meliaceae) yielded a new steroid (2\alpha, 3\beta, 4\beta-trihydroxypregnan-16-one) and 2 known steroids (2\beta, 3\beta, 4\beta-trihydroxypregnan-16-one and 2\alpha, 3\alpha, 4\beta-trihydroxypregnan-16-one). Their structures were elucidated through spectral studies including 2D NMR (COSY, NOESY, J-resolved, HMQC, HMBC) experiments.
Study Of Binary Complexes Of Nickel(Ii), Copper(Ii), And Vanadium(V) With Acetazolamide In Aqueous Medium By Voltammetry, İclal Bulut
Turkish Journal of Chemistry
The voltammetric behaviour of acetazolamide, the systemic carbonic anhydrase inhibitor, in the presence of some metal ions (Cu(II), Ni(II), and V(V)) were investigated using square-wave and cyclic voltammetry in physiological pH (pH 7.4). Square-wave voltammogram of acetazolamide in the absence of metal ions gave only 1 reduction peak at -1.65 V attributed to a catalytic hydrogen peak. Three reversible peaks at -0.068, -0.262, and -0.434 V were observed for the solutions containing both copper(II) ions and acetazolamide in the SWV. The peak at -0.434 V was attributed to Cu(II)-acetazolamide complex. In the presence of acetazolamide, copper-acetazolamide complex formation was proved …
One-Pot Synthesis Of Amidoalkyl Naphthols Using Nahso_4.Sio_2 As An Efficient And Recyclable Heterogeneous Catalyst, Hamid Reza Shaterian, Hossein Yarahmadi, Majid Ghashang
One-Pot Synthesis Of Amidoalkyl Naphthols Using Nahso_4.Sio_2 As An Efficient And Recyclable Heterogeneous Catalyst, Hamid Reza Shaterian, Hossein Yarahmadi, Majid Ghashang
Turkish Journal of Chemistry
An efficient synthesis of amidoalkyl naphthols using silica supported sodium hydrogen sulphate as heterogeneous catalyst under a thermal solvent-free green procedure is described. This simple protocol offer advantages such as shorter reaction times, simple work-up, excellent yield, and recovery and reusability of the catalyst.
Performance Analysis For Direct 2-Propanol Fuel-Cell Based On Pt Containing Anode Electrocatalysts, Ni̇yazi̇ Alper Tapan, Ezgi̇ Öztürk
Performance Analysis For Direct 2-Propanol Fuel-Cell Based On Pt Containing Anode Electrocatalysts, Ni̇yazi̇ Alper Tapan, Ezgi̇ Öztürk
Turkish Journal of Chemistry
Direct 2-propanol cell performance based on Pt containing anode electrocatalyst was evaluated. Cell performance, open circuit voltage, maximum current density, and maximum power density were measured at various alcohol concentrations and cell temperatures. 2-propanol fuel cell shows the highest performance at 1 M concentration and 80 °C operating temperature. The highest practical efficiency (at the maximum power density) was found at 2 M 2-propanol concentration and 60 °C operating temperature. Parameter estimation was performed by non-linear least squares method using the Levenberg Marquardt algorithm. According to the parametric analysis, cross-over current was minimum for 0.5 M 2-propanol concentration at 40 …
Photochemical Bromination Of Substituted Indan-1-One Derivatives: Synthesis Of New Polybromoindan-1-One Derivatives, Nermi̇n Şi̇mşek Kuş
Photochemical Bromination Of Substituted Indan-1-One Derivatives: Synthesis Of New Polybromoindan-1-One Derivatives, Nermi̇n Şi̇mşek Kuş
Turkish Journal of Chemistry
The photobromination of substituted indan derivatives was studied. Four products, 2,3-dibromo-inden-1-one (5), trans-2,3-dibromoindan-1-one (6), 2,2-dibromoindan-1,3-dione (7) and 2,2-dibromoindan-1-one (8), were obtained by the bromination of indan-1-one (4). The bromination of 2-methyl indanone (9) and 3-methyl-indanone (13) gave the corresponding monobromo, dibromo, and tribromo compounds in high yield. 4-Nitro indan (16) was tribrominated under same condition reaction. The structures of these products were determined from ^1H-NMR, ^{13}C-NMR, MS, and IR data.
Chemical Constituents And Mushroom Tyrosinase Inhibition Activity Of Chloroxylon Swietenia Leaves, G. Venkatateswara Rao, K. Sambasiva Rao, Tiruganasambandham Annamalai, Narayanasamy Radhakrishnan, Triptikumar Mukhopadhyay
Chemical Constituents And Mushroom Tyrosinase Inhibition Activity Of Chloroxylon Swietenia Leaves, G. Venkatateswara Rao, K. Sambasiva Rao, Tiruganasambandham Annamalai, Narayanasamy Radhakrishnan, Triptikumar Mukhopadhyay
Turkish Journal of Chemistry
From the leaves of Chloroxylon swietenia DC., 5 known secondary metabolites, namely 6, 8-diprenylumbelliferone (1), bergaptan (2), isopimpinellin (3), tritriacontanol (4), and isoquercetrin (5), were isolated from a folklore medicinal plant. Three compounds were isolated for the first time from this genus. The structures of these compounds were elucidated by UV, IR, 1D and 2D NMR techniques. Different fractions from the leaves of C. swietenia were investigated for their tyrosinase inhibition activity.
Ctab-Assisted Hydrothermal Synthesis And Magnetic Characterization Of Ni_Xco_{1-X}Fe_2o_4 Nanoparticles (X = 0.0, 0.6, 1.0), Abdulhadi̇ Baykal, Nermi̇n Kasapoğlu, Zehra Durmuş, Hüseyi̇n Kavas, Muhammet S. Toprak, Yüksel Köseoğlu
Ctab-Assisted Hydrothermal Synthesis And Magnetic Characterization Of Ni_Xco_{1-X}Fe_2o_4 Nanoparticles (X = 0.0, 0.6, 1.0), Abdulhadi̇ Baykal, Nermi̇n Kasapoğlu, Zehra Durmuş, Hüseyi̇n Kavas, Muhammet S. Toprak, Yüksel Köseoğlu
Turkish Journal of Chemistry
Nickel ferrite, Ni_xCo_{1-x}Fe_2O_4, NPs (where x = 0.0, 0.6 and 1.0) were successfully synthesized by a rapid and reproducible CTAB-assisted hydrothermal route. The influence of different hydrolyzing agents on the particle size and magnetic behavior of Ni_xCo_{1-x}Fe_2O_4 NPs was investigated. Particles showed very high phase purity and crystallinity in powder XRD analysis. Compositions of Co, Fe, and Ni in fabricated powders were also determined by AAS and results are in very good agreement with the targeted compositions. Samples hydrolyzed using NH_3 showed no significant changes in the particle size and morphology. NH_3 hydrolyzed samples were much smaller than their NaOH …
6-Ketomethyl Phenanthridine As A New Carrier In The Construction Of A Highly Selective Fe(Iii) Ion-Selective Membrane Electrode, R. Maleki, Reza Hosseinzadeh, Hossein Mehrabi, Ali Hassanzadeh, Khalil Farhadi
6-Ketomethyl Phenanthridine As A New Carrier In The Construction Of A Highly Selective Fe(Iii) Ion-Selective Membrane Electrode, R. Maleki, Reza Hosseinzadeh, Hossein Mehrabi, Ali Hassanzadeh, Khalil Farhadi
Turkish Journal of Chemistry
A new Fe^{3+} ion-selective membrane electrode based on 6-ketomethyl phenanthridine (6-KMPT) and 1-(4-dimethyl aminophenyl)-2-(5H-phenanthridine-6-ylidene)-ethanone, which were incorporated in a plasticized polyvinyl chloride (PVC) membrane, is described. The optimized membrane demonstrated a linear dynamic range of 5.2 \times 10^{-6}-1.0 \times 10^{-2} M, with a near Nernstian slope of 19.5 \pm 1.5 mV per decade and a detection limit of 1.2 \times 10^{-6} M. The electrode showed high selectivity for Fe^{3+} ions in comparison to other metal ions. The effect of membrane composition on the potential response of the electrode was studied. The best performance was observed for the membrane comprised of …
Bromination Of Tetrachlorobenzobarrelene: Polyhalogenated Benzobicyclics, Mehmet Emi̇n Şengül, Demet Demi̇rci̇ Gülteki̇n, Selçuk Eşsi̇z, Ari̇f Daştan
Bromination Of Tetrachlorobenzobarrelene: Polyhalogenated Benzobicyclics, Mehmet Emi̇n Şengül, Demet Demi̇rci̇ Gülteki̇n, Selçuk Eşsi̇z, Ari̇f Daştan
Turkish Journal of Chemistry
The low and high temperature bromination reaction of tetrachlorobenzobarrelene was studied and the possible role of a neighboring group in rearrangements was investigated. New polyhalogenated benzobicyclic compounds were synthesized. All compounds were characterized properly using NMR spectroscopy.
Rapid Synthesis Of New Poly(Amide-Imide)S Based On N-(4-Carboxy Phenyl) Trimellitimide And Hydantoin Derivatives Under Microwave Irradiation, Khalil Faghihi, Mohammad Gholizadeh
Rapid Synthesis Of New Poly(Amide-Imide)S Based On N-(4-Carboxy Phenyl) Trimellitimide And Hydantoin Derivatives Under Microwave Irradiation, Khalil Faghihi, Mohammad Gholizadeh
Turkish Journal of Chemistry
Six new poly (amide-imide)s (6a-f) were prepared under microwave irradiation by polycondensation reaction of diacid chloride (4) with 6 different derivatives of hydantoins (5a-f) using O-cresol as a microwave absorbent. These new PAIs were obtained in high yield and with inherent viscosities between 0.15 and 0.25 dL/g. The resulting poly(amide-imide)s were characterized by elemental analysis, viscosity measurements, thermal gravimetric analysis (TGA & DTG), solubility test, and FT-IR spectroscopy. N-(4-chlorocarbonyl phenyl) trimellitimide acid chloride (4) was prepared by a 2-step reaction. First trimellitic anhydride (1) was reacted with 4-amino benzoic acid (2) in acetic acid solution and the resulting imide-acid [N-(4-carboxy …
Synthesis And Characterization Of Tetraoxime Ligand, Bis-[(2e,3e,2´E)-3,3´-(1,2-Phenylene-Dinitrilo)Dibutan-2-One Dioxime] And Its Dinuclear And Tetranuclear Copper(Ii)/Nickel(Ii) Complexes, Nevi̇n Karaböcek, Pinar Ekmekçi̇oğlu, Asligül Küçükdumlu, Serdar Karaböcek
Synthesis And Characterization Of Tetraoxime Ligand, Bis-[(2e,3e,2´E)-3,3´-(1,2-Phenylene-Dinitrilo)Dibutan-2-One Dioxime] And Its Dinuclear And Tetranuclear Copper(Ii)/Nickel(Ii) Complexes, Nevi̇n Karaböcek, Pinar Ekmekçi̇oğlu, Asligül Küçükdumlu, Serdar Karaböcek
Turkish Journal of Chemistry
A new tetraoxime, (H_4L), was prepared in EtOH by reacting biphenyl-3,3´,4,4´-tetramine with butane-2,3-dione oxime. The tetraoxime ligand was characterized by elemental analyses, H-NMR and ^{13}C-NMR, IR, and mass spectral studies. Dinuclear copper(II), nickel(II) and tetranuclear copper(II) complexes of tetraoxime ligand were prepared and characterized by elemental analyses, magnetic moments, IR, and mass spectral studies. In the dinuclear metal complexes, metal:ligand ratio was found as 2:1. Elemental analyses and stoichiometric and spectroscopic data of the metal complexes indicated that the metal ions were coordinated to the nitrogen atoms of oxime groups (C=N). In addition, total energy and heat formation for ligand …
Microwave-Assisted Synthesis Of Some Metal-Free Phthalocyanine Derivatives And A Comparison With Conventional Methods Of Their Synthesis, Özlem Seven, Bi̇rcan Di̇ndar, Burak Gülteki̇n
Microwave-Assisted Synthesis Of Some Metal-Free Phthalocyanine Derivatives And A Comparison With Conventional Methods Of Their Synthesis, Özlem Seven, Bi̇rcan Di̇ndar, Burak Gülteki̇n
Turkish Journal of Chemistry
Synthesis of metal-free 2,9(10),16(17),23(24)-tetra(3,5- dimethylphenoxy) phthalocyanine, 2,9(10),16(17), 23(24)-tetra(4- tert-butylphenoxy) phthalocyanine, and 2,9(10),16(17),23(24)-tetra(3,5- di-tert-butyl-4-hydroxyphenyl) phthalocyanine was carried out via microwave irradiation. Furthermore, pentanol and lithium were used for the first time in the synthesis of metal-free phthalocyanine under microwave irradiation as a solvent and a base-catalyst, respectively. The microwave irradiation experiments were performed in a MARS5 with a CEM XP-1500 vessel. In addition, these compounds were obtained with conventional heating procedures to compare them with those obtained with microwave irradiation. The compounds were characterized by elemental and spectroscopic analysis, including UV-Vis, H NMR, FT-IR, and MALDI-TOF mass data. In particular, both …