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Full-Text Articles in Physical Sciences and Mathematics
Effect Of Microfluidic Channel Integration Onto Gold Microelectrode On Its Redox Electrochemistry, Ahmet Uçar, Zahraa Ali Hajool, Hamed Ghorbanpoor, Reza Didarian, Fatma Doğan Güzel
Effect Of Microfluidic Channel Integration Onto Gold Microelectrode On Its Redox Electrochemistry, Ahmet Uçar, Zahraa Ali Hajool, Hamed Ghorbanpoor, Reza Didarian, Fatma Doğan Güzel
Turkish Journal of Chemistry
Microfluidic systems have attracted significant interest in recent years as they are extensively employed in lab-on-chip and organ-on-chip research. Their combination with electrochemical platforms offers many advantages, promising a high potential for sensing applications, still the microfluidic-channel integration onto electrodes might induce challenges related to changes in signal-tonoise ratios and mass transport conditions. In this study, we investigated the effect of microfluidic channel integration in redox behavior of thermally deposited gold thin film microelectrodes by voltammetric (CV and SWV) electrochemical measurements. Using different dimensions of PDMS microfluidic channels (i.e. widths of 50, 100, 250, and 500 μm) and a constant …
New Bis-Isoxazole With Monoterpenic Skeleton: Regioselective Synthesis, Spectroscopicinvestigation, Electrochemical, And Density Functional Theory (Dft) Studies, Ali Oubella, Meryem Hrimla, Mouhi Eddine Hachim, Mourad Fawzi, Abdoullah Bimoussa, Lahoucine Bahsis, Aziz Boutouil, Aziz Auhmani, Abdelkhalek Riahi, My Youssef Ait Itto
New Bis-Isoxazole With Monoterpenic Skeleton: Regioselective Synthesis, Spectroscopicinvestigation, Electrochemical, And Density Functional Theory (Dft) Studies, Ali Oubella, Meryem Hrimla, Mouhi Eddine Hachim, Mourad Fawzi, Abdoullah Bimoussa, Lahoucine Bahsis, Aziz Boutouil, Aziz Auhmani, Abdelkhalek Riahi, My Youssef Ait Itto
Turkish Journal of Chemistry
A novel bis-isoxazole was synthesized from (R)-Carvone and p-methylbenzaldoxime, via two successive [3+2] cycloaddition reactions (32CA). The newly obtained bis-isoxazole has been fully characterized by HRMS and NMR spectroscopy. The HMBC experiment was performed to determine the stereo and the regioselectivity of the reaction. The electrochemical behavior of the studied compound, in oxidation and reduction processes, was examined using the cyclic voltammetry technique. In addition, the regioselectivity of the [3+2] cycloaddition reaction and the molecular structure of the title compound was performed by density functional theory (DFT). The HOMO and LUMO orbitals were investigated to determine the electronic properties of …
Insight Into Electrochemical Degradation Of Cartap (In Padan 95sp) By Boron-Doped Diamond Electrode: Kinetic And Effect Of Water Matrices, Hoang Nguyen
Turkish Journal of Chemistry
In this work, the kinetic electrochemical degradation of Cartap (CT) (in Padan 95 SP) at boron-doped diamond (BDD) electrode was investigated. This study indicated that the degradation of CT underwent both direct and indirect oxidations. Water matrices can either accelerate or inhibit the removal efficiency of CT: adding 15 mM Cl- improved kCT from 0.039 min-1 to 0.054 min-1 (increased by 38%), while kCT decreased by 61.5% and 64% when increasing the concentration of HCO3- and humic acid (HA) to 15 mM and 15 mg L-1, respectively. CT degradation was inhibited …
Novel Nonperipheral Octa-3-Hydroxypropylthio Substituted Metallo-Phthalocyanines: Synthesis, Characterization, And Investigation Of Their Electrochemical, Photochemical And Computational Properties, Ni̇lgün Kabay, Yasemi̇n Bayğu, Meti̇n Ak, İzzet Kara, Esra Nur Kaya, Mahmut Durmuş, Yaşar Gök
Novel Nonperipheral Octa-3-Hydroxypropylthio Substituted Metallo-Phthalocyanines: Synthesis, Characterization, And Investigation Of Their Electrochemical, Photochemical And Computational Properties, Ni̇lgün Kabay, Yasemi̇n Bayğu, Meti̇n Ak, İzzet Kara, Esra Nur Kaya, Mahmut Durmuş, Yaşar Gök
Turkish Journal of Chemistry
The current study describes the synthesis, electrochemical, computational, and photochemical properties of octa (3-hydroxypropylthio) substituted cobalt (II) (4), copper (II) (5), nickel (II) (6) and zinc(II) (7) phthalocyanine derivatives. These novel compounds were characterized by elemental analysis, 1H, 13C NMR, FT-IR, UV-Vis, and MS. The redox behaviors of these metallo-phthalocyanines were investigated by the cyclic voltammetric method. The optimized molecular structure and gauge-including atomic orbital (GIAO) 1H and 13C NMR chemical shift values of these phthalocyanines in the ground state had been calculated by using B3LYP/6-31G(d,p) basis set. The outcomes of the optimized molecular structure were given and compared with …
Low Loaded Pt-Co Catalyst Surfaces Optimized By Magnetron Sputtering Sequentialdeposition Technique For Pem Fuel Cell Applications: Physical And Electrochemicalanalysis On Carbon Paper Support, Osman Öztürk, Aydin Haşi̇moğlu, Oğuz Kaan Özdemi̇r, İnci̇ Karaaslan, Ali̇ Şems Ahsen
Low Loaded Pt-Co Catalyst Surfaces Optimized By Magnetron Sputtering Sequentialdeposition Technique For Pem Fuel Cell Applications: Physical And Electrochemicalanalysis On Carbon Paper Support, Osman Öztürk, Aydin Haşi̇moğlu, Oğuz Kaan Özdemi̇r, İnci̇ Karaaslan, Ali̇ Şems Ahsen
Turkish Journal of Chemistry
A series of thin Pt-Co films with different metal ratios were deposited by using the sequential cosputtering directly on a commercial hydrophobic carbon paper substrate at room temperature and in ultra-high vacuum (UHV) conditions. Their electrocatalytic properties toward the oxygen reduction reaction were investigated in 0.5 M H2SO4 solution by means of cyclic voltammetry (CV) and linear sweep voltammetry (LSV) on rotating disc electrode (RDE). The results showed that Pt particles, deposited by dc-magnetron gun, surround the large Co-clusters deposited by rf-magnetron gun. In addition, the increase of Co content led to an increase in the electrochemical active surface area …
Investigation Of Electrochemical Behavior Of Potassium Ferricyanide/Ferrocyanide Redox Probes On Screen Printed Carbon Electrode Through Cyclic Voltammetry And Electrochemical Impedance Spectroscopy, Yücel Koç, Uğur Morali, Sali̇m Erol, Hüseyi̇n Avci
Investigation Of Electrochemical Behavior Of Potassium Ferricyanide/Ferrocyanide Redox Probes On Screen Printed Carbon Electrode Through Cyclic Voltammetry And Electrochemical Impedance Spectroscopy, Yücel Koç, Uğur Morali, Sali̇m Erol, Hüseyi̇n Avci
Turkish Journal of Chemistry
Potassium ferricyanide, potassium ferrocyanide, and their combination system are widely used redox probes for electrochemical impedance spectroscopy (EIS) characterization. In this work, electrochemical behavior of K3Fe(CN)6, K4Fe(CN) 6, and K3Fe(CN)6/K4Fe(CN)6 redox probes at five different concentrations using a screen printed carbon electrode (SPCE) by cyclic voltammetry (CV) and EIS methods was analyzed. Redox potentials were observed as a result of anodic and cathodic peak with CV analysis with determination 10 mM appropriate concentration through 0.01 mM, 0.1 mM, 1 mM, and 100 mM. In addition, with EIS analysis, each redox probe was simulated according to two different Randles circuit models …
Synthesis, Optical, And Structural Properties Of Bisphenol-Bridgedaromatic Cyclic Phosphazenes, Bünyemi̇n Çoşut, Burcu Topaloğlu Aksoy, Süreyya Oğuz Tümay, Ahmet Şenocak, Serkan Yeşi̇lot
Synthesis, Optical, And Structural Properties Of Bisphenol-Bridgedaromatic Cyclic Phosphazenes, Bünyemi̇n Çoşut, Burcu Topaloğlu Aksoy, Süreyya Oğuz Tümay, Ahmet Şenocak, Serkan Yeşi̇lot
Turkish Journal of Chemistry
Phenoxy- and naphthoxy-substituted bisphenol-bridged cyclic phosphazenes were synthesized in 2 steps and their thermal, photophysical, and electrochemical properties were investigated. The structures of the cyclic phosphazene compounds were determined by ESI-MS mass spectrometry and $^{1}$H, $^{13}$C, and $^{31}$P NMR spectroscopies. The photophysical studies of phenoxy- and naphthoxy-substituted bridged cyclophosphazenes were investigated by means of absorption and fluorescence spectroscopies in different solvents. Thermal and electrochemical properties of the target compounds were also studied. Furthermore, the excimer emissions through intramolecular interactions in solution and in solid state were investigated by fluorescence spectroscopy and the theoretical calculations were performed in detail using DFT.
Electrochemical Oxidation Of Curcuminoids: An Experimental And Computational Investigation, Zeynep Kalaycioğlu, Nurgül Karadaş, Mehmet Emi̇n Çinar, Si̇bel Ayşil Özkan, Duri̇şehvar Özer Ünal, Ayşegül Gölcü, Fatma Bedi̇a Eri̇m
Electrochemical Oxidation Of Curcuminoids: An Experimental And Computational Investigation, Zeynep Kalaycioğlu, Nurgül Karadaş, Mehmet Emi̇n Çinar, Si̇bel Ayşil Özkan, Duri̇şehvar Özer Ünal, Ayşegül Gölcü, Fatma Bedi̇a Eri̇m
Turkish Journal of Chemistry
Curcuminoids, reported to have important biological properties, such as antioxidant, anti-Alzheimer, and antidiabetic properties, comprise curcumin (CRM; 1,7-bis [4-hydroxy-3-methoxyphenyl]-1,6-heptadiene-3,5-dione) and its derivatives demethoxycurcumin (DMC; (E,6E)-1-(3,4-dimethoxy-cyclohexyl)-7-(3,4-dimethoxyphenyl)hepta-1,6-diene-3,5-dione) and bisdemethoxycurcumin (BDMC; 1,7-bis[4-hydroxyphenyl]-1,6-heptadiene-3,5-dione). Their electrochemical oxidations are thoroughly explored by applying cyclic and differential pulse voltammetric techniques. The dependence of current intensities and potentials on pH, concentration, scan rate, and nature of the buffer was investigated. The outcome is supported by density functional theory computations indicating the transfer of 4-e$^{-}$/H$^{+}$, 6-e$^{-}$/H$^{+}$, and 8-e$^{-}$/H$^{+}$ couples involved in the oxidation mechanisms of CRM, DMC, and BDMC, respectively, leading to the formation of the same oxidized product.
Amperometric Urea Biosensor Based On Immobilized Urease On Polypyrrole And Macroporous Polypyrrole Modified Pt Electrode, Maliheh Hosseinian, Ghasem Najafpour, Ahmad Rahimpour
Amperometric Urea Biosensor Based On Immobilized Urease On Polypyrrole And Macroporous Polypyrrole Modified Pt Electrode, Maliheh Hosseinian, Ghasem Najafpour, Ahmad Rahimpour
Turkish Journal of Chemistry
Biosensing of urea by a biosensor as a direct detection method at ambient temperature and pressure instead of chromatography leads to a significant reduction in processing costs. Amperometric biosensors based on urease immobilization on macroporous polypyrrole (MPPy) and pyrrole on the surface of a Pt electrode were developed. Applying cyclic voltammetry (CV), we demonstrated the synthesis of MPPy using monodispersed polystyrene spheres (460 nm) as a template. CV and chronoamperometric studies were conducted to evaluate the electrochemical current of the modified electrodes. For the electrode with polypyrrole (PPy), the biosensor response was linear in the range of 1.67--8.32 mM (R$^{2}$ …
In Silico And In Vitro Evaluation Of The Biological Activity Of Some Organic Sulfur-Containing Compounds, Victoria Osipova, Maria Polovinkina, Anastasia Osipova, Yulia Gracheva, Andrey Okhlobystin
In Silico And In Vitro Evaluation Of The Biological Activity Of Some Organic Sulfur-Containing Compounds, Victoria Osipova, Maria Polovinkina, Anastasia Osipova, Yulia Gracheva, Andrey Okhlobystin
Turkish Journal of Chemistry
It was predicted, using the Prediction of Activity Spectra for Substances online software, that organic sulfur-containing compounds 2,6-di-tert-butyl-4-mercaptophenol (1), 2,6-di-tert-butyl-4-(3-mercaptopropyl)phenol (2), bis-3-[3,5-di-tert-butyl-4-hydroxyphenyl)propyl] sulfide (3), bis(3,5-di-tert- butyl-4-hydroxyphenyl) disulfide (4), diphenyl disulfide (5), dibenzyl disulfide (6), dibutyl disulfide (7), di-tert-butyl disulfide (8), diallyl disulfide (9), and methyl propyl trisulfide (10) could possess antioxidant activity and act as active scavengers of oxygen metabolites. The antiradical activity of these species was analyzed and it was shown that they were able to react with electrochemically generated the superoxide anion radical. The rate constants for reactions of 1-10 with the superoxide anion radical were calculated. The …
Multiwall Carbon Nanotube Paste Electrode As A Sensor For Sensitive Determination Of Deferasirox In The Presence Of Uric Acid: Application For The Analysis Of Pharmaceutical And Biological Samples, Golnaz Parvizi Fard, Reza Emamali Sabzi
Multiwall Carbon Nanotube Paste Electrode As A Sensor For Sensitive Determination Of Deferasirox In The Presence Of Uric Acid: Application For The Analysis Of Pharmaceutical And Biological Samples, Golnaz Parvizi Fard, Reza Emamali Sabzi
Turkish Journal of Chemistry
In this work, the electrochemical oxidation of deferasirox at a multiwall carbon nanotube paste electrode (MWCNTPE) was described. The electrochemical behavior of deferasirox was studied using cyclic voltammetry and chronoamperometry techniques and parameters such as charge transfer coefficient ($\alpha )$, the number of electrons involved in the rate-determining step ($n_{a})$, and diffusion coefficient ($D)$ were calculated. The capability of the electrode for the determination of deferasirox at low concentrations was investigated using the differential pulse voltammetry technique. It was found that the calibration graph of deferasirox was linear in the concentration range of 0.16-16.5 $\mu $M and its detection limit …
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.
Electrochemical Properties Of 1,3-Disubstituted Methyl Methoxy Phenyl-5-Phenylformazans And Comparison With Spectral Properties, Habi̇be Tezcan, Güler Ekmekci̇, Mehmet Levent Aksu
Electrochemical Properties Of 1,3-Disubstituted Methyl Methoxy Phenyl-5-Phenylformazans And Comparison With Spectral Properties, Habi̇be Tezcan, Güler Ekmekci̇, Mehmet Levent Aksu
Turkish Journal of Chemistry
In this study, electrochemical behaviors of formazans were investigated. The compounds contained CH_3 and OCH_3 groups at the o-, m-, and p-positions of the 1-phenyl ring and an OCH_3 group at the p-position of the 3-phenyl ring. Their electrochemical behaviors, such as the number of electrons transferred, diffusion coefficients, and heterogeneous rate constants, were studied by cyclic voltammetry, ultramicrodisk electrode, and chronoamperometry. Possible mechanisms were proposed based upon the data obtained. There was a correlation between the absorption and electrochemical properties. A linear correlation was obtained between \lambda_{\max} and E_{red2} and Hammett substituent coefficients with E_{red2} and k_s values.
Properties Of The Mixed Adsorption Layer: Neutral Detergent-Tetramethylthiourea At Interface Electrode/Solution, Jolanta Nieszporek, Dorota Sienko, Dorota Gugala-Fekner, Malgorzata Klin
Properties Of The Mixed Adsorption Layer: Neutral Detergent-Tetramethylthiourea At Interface Electrode/Solution, Jolanta Nieszporek, Dorota Sienko, Dorota Gugala-Fekner, Malgorzata Klin
Turkish Journal of Chemistry
The mixed adsorption layers of tetramethylthiourea and a neutral detergent formed at the electrode surface in 1 M NaClO_4 are described in this paper. The systems were characterized by the measurement of differential capacity, zero charge potential, and surface tension at the same potential. The data were analyzed to obtain the surface pressure and relative surface excess of tetramethylthiourea as a function of electrode charge and bulk concentration of the studied compounds. The values of the lateral interaction parameters, obtained in the presence and in the absence of decanoyl-N-methylglucamide (C_{17}H_{35}NO_6), change differently depending on the isotherm used, but \Delta G° …
Synthesis And Structural And Electrochemical Characterization Of Novel Macrocyclic Vic-Dioxime Ligand And Its Mononuclear Transition And Nontransition Metal Complexes, Pervi̇n Deveci̇, Bi̇lge Taner, Zeynel Kiliç, Ali̇ Osman Solak, Emi̇ne Özcan
Synthesis And Structural And Electrochemical Characterization Of Novel Macrocyclic Vic-Dioxime Ligand And Its Mononuclear Transition And Nontransition Metal Complexes, Pervi̇n Deveci̇, Bi̇lge Taner, Zeynel Kiliç, Ali̇ Osman Solak, Emi̇ne Özcan
Turkish Journal of Chemistry
The reaction of N-(4-aminophenyl)aza-15-crown-5 (1) with anti-chlorophenylglyoxime (2) produces a novel azacrown ether containing vic-dioxime, N-(4-aminophenyl)aza-15-crown-5-phenylglyoxime (LH_2). LH_2 reacts with Ni(II), Cu(II), Co(II), Cd(II), and Zn(II) ions to yield the mononuclear transition and nontransition metal complexes [M(LH)_2] (M = Ni and Cu), [M(LH)_2(H_2O)_2] (M = Co), and [M(LH)(H_2O)(Cl)] (M = Cd and Zn). The structural features of LH_2 were studied using several techniques including elemental analysis, Fourier transform infrared spectroscopy (FT-IR), ultraviolet visible (UV-Vis), mass spectrometry (MS), 1-dimensional (1D) ^1H-NMR and ^{13}CNMR, distortionless enhancement by polarization transfer (DEPT) 2-dimensional (2D) heteronuclear single-quantum coherence (HSQC), and heteronuclear multiple-bond correlation (HMBC) techniques. …
Performance Evaluation Of Platinum-Based Catalysts For The Development Of Proton Exchange Membrane Fuel Cells, Abdul Sattar Ali Khan, Riaz Ahmed, Muhammad Latif Mirza
Performance Evaluation Of Platinum-Based Catalysts For The Development Of Proton Exchange Membrane Fuel Cells, Abdul Sattar Ali Khan, Riaz Ahmed, Muhammad Latif Mirza
Turkish Journal of Chemistry
Platinum-based catalysts are considered the most efficient catalysts for triggering electrochemical reactions in proton exchange membrane (PEM) fuel cells. In the present study, commercial catalysts containing 10% and 30% Pt supported on Vulcan XC-72 carbon were studied to assess their performance in PEM fuel cells. Both catalysts consisted of Pt particles of almost the same size. The utility of these catalysts in PEM fuel cells was studied by finding the real surface area and rate of electro-oxidation of methanol in 0.5 M H_2SO_4 by using cyclic voltammetry. The methanol oxidation reaction was used for characterization of catalysts of PEM fuel …
Electrochemical Properties Of 1-(O-, M-, P-Nitrophenyl)-3-(M-Nitrophenyl)- 5-Phenylformazans And Their Nickel Complexes, Habi̇be Tezcan, Mehmet Levent Aksu
Electrochemical Properties Of 1-(O-, M-, P-Nitrophenyl)-3-(M-Nitrophenyl)- 5-Phenylformazans And Their Nickel Complexes, Habi̇be Tezcan, Mehmet Levent Aksu
Turkish Journal of Chemistry
The electrochemical properties of NO_2 formazans and their Ni(II) complexes were investigated. The investigated formazans included a NO_2 group at the o-, m-, and p-positions of the 1-phenyl ring and at the m-position of the 3-phenyl ring. The oxidation and reduction peak potentials, number of electrons transferred, diffusion coefficient, heterogeneous rate constant, and possible reaction mechanism of the compounds were determined with the use of cyclic voltammetry (CV), ultramicrodisc electrodes (UMEs), and chronoamperometry (CA). The peak potentials (E}_{ox1}) were observed to shift towards more anodic potentials in formazans and more cathodic potentials in their respective Ni complexes compared to unsubstituted …
A Study Of Growth And Breakdown Of Passive Film On Copper Surface By Electrochemical Impedance Spectroscopy, Amtul Naseer, Athar Yaseen Khan
A Study Of Growth And Breakdown Of Passive Film On Copper Surface By Electrochemical Impedance Spectroscopy, Amtul Naseer, Athar Yaseen Khan
Turkish Journal of Chemistry
Electrochemical impedance spectroscopy (EIS) and cyclic voltammetry were used to investigate the oxide layer formed on a copper disc electrode and the changes that took place when treated potentiostatically in the range of -0.3 V to 0.9 V in aqueous buffer solution of pH 9.2. Equivalent circuits were used to model the response of the electrode, initially at equilibrium to an applied potential. These circuits were proposed for different potential ranges in order to illustrate the Cu/oxide/electrolyte system and its properties in terms of 2 interfaces. A criterion for the applicability of equivalent circuit models was discussed. Changes in the …
Comparison Of Catalytic Activities Of Carbon Supported Pt And Pt-Ru Catalysts For Methanol Oxidation In Neutral And Basic Media By Cyclic Voltammetry, Abdul Sattar Ali Khan, Riaz Ahmed, Muhammad Latif Mirza
Comparison Of Catalytic Activities Of Carbon Supported Pt And Pt-Ru Catalysts For Methanol Oxidation In Neutral And Basic Media By Cyclic Voltammetry, Abdul Sattar Ali Khan, Riaz Ahmed, Muhammad Latif Mirza
Turkish Journal of Chemistry
The catalytic activities of an equal amount of 3 different carbon supported catalysts containing 10% Pt, 20% Pt + 10% Ru, and 30% Pt were evaluated in neutral and basic media for methanol oxidation by cyclic voltammetry. The prominent oxidation peak for methanol appeared in the forward anodic sweep at around 1.0 V in neutral medium, while in basic medium it appeared at significantly lower potential close to 0.2 V. The peak current for methanol oxidation was higher on a catalyst containing higher Pt loading. The comparison of polarization behavior of 20% Pt + 10% Ru and 30% Pt catalysts …
Photophysical Properties And Electrochemistry Of The N,N'-Bis-N-Butyl Derivative Of Naphthalene Diimide, Yevgen Posokhov, Serap Alp, Banu Köz, Yusuf Di̇lgi̇n, Siddik İçli̇
Photophysical Properties And Electrochemistry Of The N,N'-Bis-N-Butyl Derivative Of Naphthalene Diimide, Yevgen Posokhov, Serap Alp, Banu Köz, Yusuf Di̇lgi̇n, Siddik İçli̇
Turkish Journal of Chemistry
The spectral-luminescent properties and electrochemistry of the N,N'-bis-n-butyl derivative of naphthalene diimide were studied. The main photophysical parameters (quantum yield, rate constants of fluorescence and of non-radiative deactivation and fluorescence lifetime) were determined. The LUMO value (-3.51 eV) was determined by cyclic voltammetry. The N,N'-bis-n-butyl derivative of naphthalene diimide (BBND) shows 2 reversible reduction steps (-1.19 V and -1.75 V vs. Ferrocene) in chloroform. Quenching the fluorescence emissions of aromatic donor molecules in acetonitrile revealed the electron acceptor ability of the studied naphthalene diimide derivative. It has been found that, in contrast to perylene diimide derivatives, which form \pi-electron donor-acceptor …
A Novel, Semi-Pilot Scale Electrolysis System For The Production Of P-Aminophenol, Kamran Polat
A Novel, Semi-Pilot Scale Electrolysis System For The Production Of P-Aminophenol, Kamran Polat
Turkish Journal of Chemistry
Cyclic voltammetry (CV) and preparative electrolysis techniques were used to investigate the reduction of nitrobenzene into (NB) p-aminophenol (p-Ap). The electrodes used in CV experiments were glassy carbon (GC), TiO_{2}/Ti, Sn and Pb. The preparative electrolyses were carried out by the use of Pb, Sn, carbon cloth and TiO_{2}/Ti electrodes. The CV data were evaluated according to Nicholson-Shain criteria, and it was deduced that the reductions on TiO_{2}/Ti and GC electrodes were irreversible and monitored by an electrochemical-chemical-electrochemical mechanism. No reduction peak was observed with Sn and Pb electrodes. Preparative electrolyses were carried out under current-controlled conditions in the presence …
Steric Effects On The Oxidation Potential Of 1-Aryl Thioglycosides, Mehmet A. Oturan, Maurice Medebielle, Shirish A. Patil, Robert S. Klein
Steric Effects On The Oxidation Potential Of 1-Aryl Thioglycosides, Mehmet A. Oturan, Maurice Medebielle, Shirish A. Patil, Robert S. Klein
Turkish Journal of Chemistry
The electrochemical oxidation of several 1-arylthioglycosides has been studied by cyclic voltammetry in acetonitrile. We found that the oxidation potential of the \alpha anomer always occurs at a less positive oxidation potential than of the \beta anomer. The difference in the oxidation potential depends on the substituent attached on the C-3 of the sugar moiety and is greatly influenced by the stability of the radical cation obtained after the first electron transfer.
Electrochemical Investigation Of 4'-Haloderivatives Of N,N-Dimethyl-4-Aminoazobenzene, Mustafa Uçar, Ali̇ Osman Solak, M. Levent Aksu, Mehmet Toy
Electrochemical Investigation Of 4'-Haloderivatives Of N,N-Dimethyl-4-Aminoazobenzene, Mustafa Uçar, Ali̇ Osman Solak, M. Levent Aksu, Mehmet Toy
Turkish Journal of Chemistry
In this study, the electrochemical behaviour of 4' -halogene-N,N-dimethyl-4-aminoazobenzene derivatives were investigated using various polarographic and voltammetric methods. The peak potentials of these derivatives were observed to shift towards negative values with increase in pH. The standard rate constants were determined with (Laviron technique) or without (Nicholson and Klingler-Kochi techniques) taking the adsorption phenomena into account. The diffusion coefficients were calculated from the cyclic voltammetric data using the method developed by Garrido. The amount of adsorbed substances (surface excess values) and transfer coefficients for the electron transfer were also determined. These compounds can be quantitatively determined between 1 x 10^{-5} …
Investigations On The Electrochemical Surface Treatment Of Carbon Fibers, Erdal Bayramli, Levent Toppare, Naci̇ Kutay Eri̇nç
Investigations On The Electrochemical Surface Treatment Of Carbon Fibers, Erdal Bayramli, Levent Toppare, Naci̇ Kutay Eri̇nç
Turkish Journal of Chemistry
Desized polyacrylonitrile (PAN) based carbon fibers (CF) were chemically and electrochemically oxidized and reduced. CF surfaces were activated via cyclic voltammetry studies with anodic and cathodic scans. The changes in CF surfaces were studied by contact angle measurements. Lifshitz-van der Waals and acid-base components of single fibers were determined. In general, oxidation resulted in the formation of an acidic surface energy component and reduction gave rise to no change in the number of basic functionalities at the CF surface.