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Full-Text Articles in Chemistry
The Single Nucleotide Ss-Arrestin2 Variant, A248t, Resembles Dynamical Properties Of Activated Arrestin, Özge Şensoy
The Single Nucleotide Ss-Arrestin2 Variant, A248t, Resembles Dynamical Properties Of Activated Arrestin, Özge Şensoy
Turkish Journal of Chemistry
ß-arrestins are responsible for termination of G protein-coupled receptor (GPCR)-mediated signaling. Association of single nucleotide variants with onset of crucial diseases has made this protein family hot targets in the field of GPCR-mediated pharmacology. However, impact of these mutations on function of these variants has remained elusive. In this study, structural and dynamical properties of one of ß-arrestin2 (arrestin 3) variants, A248T, which has been identified in some cancer tissue samples, were investigated via molecular dynamics simulations. The results showed that the variant underwent structural rearrangements which are seen in crystal structures of active arrestin. Specifically, the "short helix" unravels …
Combined Computational And Experimental Studies On Cysteine-Sulfadiazine Adduct Formation, Nursel Açar Selçuki̇, Emi̇ne Coşkun, Ender Bi̇çer
Combined Computational And Experimental Studies On Cysteine-Sulfadiazine Adduct Formation, Nursel Açar Selçuki̇, Emi̇ne Coşkun, Ender Bi̇çer
Turkish Journal of Chemistry
The electrochemical characterization of sulfadiazine-cysteine (SD-CYS) adduct formation was performed in phosphatebuffer(pH7)onthebasisofvoltammetriccurrentandpeakpotentialmeasurements. Duetotheassociationof cysteine with sulfadiazine, the reduction peak currents of mercuric and mercurous cysteine thiolates decreased and their peak potentials simultaneously shifted to less negative potentials. By using the current changes of mercurous cysteine thiolate, it was determined that cysteine and sulfadiazine are associated with a 1:1 stoichiometry with a conditional association constant of 1.99 ×10$^{4}$ M$^{-1}$. In addition to experimental studies, a computational approach was carried out to study the geometrical parameters, electron densities, and UV-Vis absorption spectra of sulfadiazine and SDCYS adduct in water. Calculated (B3LYP/6-311++G(d,p) level) …
Design Of An Amphiphilic Hyperbranched Core/Shell-Type Polymeric Nanocarrier Platform For Drug Delivery, Ayça Bal Öztürk, Nesri̇n Oğuz, Hande Tekarslan Şahi̇n, Serkan Emi̇k, Emi̇ne Alarçi̇n
Design Of An Amphiphilic Hyperbranched Core/Shell-Type Polymeric Nanocarrier Platform For Drug Delivery, Ayça Bal Öztürk, Nesri̇n Oğuz, Hande Tekarslan Şahi̇n, Serkan Emi̇k, Emi̇ne Alarçi̇n
Turkish Journal of Chemistry
An amphiphilic core/shell-type polymer-based drug carrier system (HPAE- PCL-b-MPEG), composed of hyperbranched poly(aminoester)-based polymer (HPAE) as the core building block and poly(ethylene glycol)-bpoly(ε-caprolactone) diblock polymers (MPEG-b-PCL) as the shell building block, was designed. The synthesized polymers were characterized with FTIR, $^{1}$H NMR, $^{13}$C NMR, and GPC analysis. Monodisperse HPAE-PCL-bMPEG nanoparticles with dimensions of
Arene Diazonium Saccharin Intermediates: A Greener And Cost-Effective Alternative Method For The Preparation Of Aryl Iodide, Lia Zaharani, Nader Ghaffari Khaligh, Zohreh Shahnavaz, Mohd Rafie Johan
Arene Diazonium Saccharin Intermediates: A Greener And Cost-Effective Alternative Method For The Preparation Of Aryl Iodide, Lia Zaharani, Nader Ghaffari Khaligh, Zohreh Shahnavaz, Mohd Rafie Johan
Turkish Journal of Chemistry
In the current protocol, the arene diazonium saccharin derivatives were initially produced from various substituted aromatic amines; subsequently, these intermediates were treated with a greener organic iodide for the preparation of the aryl iodide. We tried to choose low-cost, commercially available, biodegradable, recoverable, ecofriendly, and safe reagents and solvents. The arene diazonium saccharin intermediates could be stored in the liquid phase into a refrigerator for a long time with no significant loss activity. The outstanding merits of the current protocol (a) included the partial recovering of saccharin and tetraethylammonium salt, (b) reduce the use of solvents and the reaction steps …
Synthesis And Effect Of Substituent Position, Metal Type On The Electrochemical Properties Of (3-Morpholin-4-Ylpropoxy) Groups Substituted Cobalt, Manganese Phthalocyanines, Zekeri̇ya Biyiklioğlu, Hüseyi̇n Baş
Synthesis And Effect Of Substituent Position, Metal Type On The Electrochemical Properties Of (3-Morpholin-4-Ylpropoxy) Groups Substituted Cobalt, Manganese Phthalocyanines, Zekeri̇ya Biyiklioğlu, Hüseyi̇n Baş
Turkish Journal of Chemistry
In this work, 4-(3-morpholin-4-ylpropoxy)phthalonitrile 2, 3-(3-morpholin-4-ylpropoxy)phthalonitrile 3, Co(II)Pc and Mn(III)Pcs containing (3-morpholin-4-ylpropoxy) groups at peripheral and nonperipheral positions were synthesized. Phthalonitrile derivatives (2 and 3), Co(II)Pc and Mn(III)Pcs (2a, 2b, 3a, 3b) were characterized by using FT-IR, NMR (only for 2 and 3), mass and UV-Vis (except 2 and 3) spectral data techniques. Also, electrochemistry of (3-morpholin-4-ylpropoxy) group substituted Co(II)Pc and Mn(III)Pcs were inspected by using cyclic voltammetry. Electrochemical studies show that (3-morpholin-4-ylpropoxy) group substituted Co(II)Pc and Mn(III)Pcs electropolymerized on the Pt working electrode.
Gas Phase Polymerization Of Ethylene Towards Uhmwpe, Gözde Geçi̇m, Ertuğrul Erkoç
Gas Phase Polymerization Of Ethylene Towards Uhmwpe, Gözde Geçi̇m, Ertuğrul Erkoç
Turkish Journal of Chemistry
For the first time, ultra-high molecular weight polyethylene (UHMWPE) was produced in gas phase process with a new fluidized bed concept where the solids are dispersed phase and the gas is bulk phase as opposed to conventional fluidized bed reactors (FBRs). With this concept, UHMWPE with average molecular weights about 1-6,9$\, \times \, $10$^{6}$ g moles$^{-1}$ were produced with a commercial supported Ziegler-Natta catalyst by using a gas phase mini semibatch reactor system. Additionally, optimum conditions of gas phase polymerization for the best results of productivity, catalyst activity, molecular weight and crystallinity were determined by Taguchi experimental design and catalyst …
Colorimetric Cadmium Ion Detection In Aqueous Solutions By Newly Synthesized Schiff Bases, Zi̇ya Aydin, Mustafa Keleş
Colorimetric Cadmium Ion Detection In Aqueous Solutions By Newly Synthesized Schiff Bases, Zi̇ya Aydin, Mustafa Keleş
Turkish Journal of Chemistry
Two newly synthesized Schiff bases DMCA and DMBA were used for selective detection of Cd$^{2+}$ over a wide range of other metal ions in acetonitrile (ACN)/ Tris-HCl buffer (10 mM, pH 7.32, v/v 2:1). The sensors can detect Cd$^{2+}$ ions by colour changes from colourless to orange for DMBA and yellow to reddish for DMCA. Response of the probes towards metal ions was investigated by using UV-vis spectroscopy. The complex stoichiometry between the sensors, DMBA and DMCA, and Cd$^{2+}$ was found to be 2:1 and the binding constants were calculated to be 2.65 x 10$^{12}$ M$^{-2\, }$and 4.95 x 10$^{12}$ …
Isothermal Compressibility And Isobaric Thermal Shrinkage Of A Porous $\Alpha$-Alumina Compact: Thermodynamic Calculations, Yüksel Sarikaya, Müşerref Önal, Abdullah Devri̇m Pekdemi̇r
Isothermal Compressibility And Isobaric Thermal Shrinkage Of A Porous $\Alpha$-Alumina Compact: Thermodynamic Calculations, Yüksel Sarikaya, Müşerref Önal, Abdullah Devri̇m Pekdemi̇r
Turkish Journal of Chemistry
Two methods were proposed to calculate the thermodynamic parameters of porous ceramic compacts depending on their molar volume change with applied pressure and heating temperature, respectively. Molar volume of the porous $\alpha $-alumina ($\alpha $-Al$_{2}$O$_{3})$ compact was evaluated according to literature depending on both the applied pressure at room temperature and the heating temperature at atmospheric pressure. The isothermal compressibility coefficient, Gibbs energy, and work done on the compact by compression were calculated. The thermal shrinkage coefficient and activation energy as well as the change in enthalpy, entropy and Gibbs energy were calculated for partial sintering. The spontaneous nature of …
An Anthracene Based Fluorescent Probe For The Selective And Sensitive Detection Of Chromium (Iii) Ions In An Aqueous Medium And Its Practical Application, Erman Karakuş
Turkish Journal of Chemistry
An anthracene based fluorescent probe, integrated with thiophene moiety, exhibited selective and sensitive detection of chromium (III) ions over other metal ions. Its synthesis was achieved by simple mixing of two commercially available compounds, 2-aminoanthracene, and 2-thiophenecarboxaldehyde, in onestep without the needed complex purification process. The probe molecule (ANT-Th) offered exceptional features such as "turn-on" fluorescence response, low detection limit (0.4 μM), and fast response time (< 1 min) via C$=$N bond hydrolysis. Also, a simple test paper system was developed for the rapid detection of chromium (III) ions with the naked eye.
Oxidation Of Crotyl Alcohol By N-Chloro-4-Methylbenzene Sulphonamide In Acidic Medium And In Alkaline Media In The Presence Of Os(Viii) Catalyst-A Kinetic Pathway, Priyamvada Sharma, Riya Sailani, Anita Meena, Chandra Lata Khandelwal
Oxidation Of Crotyl Alcohol By N-Chloro-4-Methylbenzene Sulphonamide In Acidic Medium And In Alkaline Media In The Presence Of Os(Viii) Catalyst-A Kinetic Pathway, Priyamvada Sharma, Riya Sailani, Anita Meena, Chandra Lata Khandelwal
Turkish Journal of Chemistry
The kinetic pathway of oxidation of crotyl alcohol by sodium salt of $N$-chloro-4-methylbenzene sulphonamide (chloramine-T) in acidic and alkaline medium has been studied. The speciation of chloramine-T has been made to suggest a proper and reasonable reaction mechanism. The thermodynamic quantities such as activation energy and activation entropy are evaluated in acidic as well as in catalysed alkaline medium. An anticipated reaction mechanism has been suggested.
Modeling And Optimization Of Simultaneous Degradation Of Rhodamine B And Acid Red 14 Binary Solution By Homogeneous Fenton Reaction: A Chemometrics Approach, Nasrin Aliasgharlou, Morteza Bahram, Pezhman Zolfaghari, Naiemeh Mohseni
Modeling And Optimization Of Simultaneous Degradation Of Rhodamine B And Acid Red 14 Binary Solution By Homogeneous Fenton Reaction: A Chemometrics Approach, Nasrin Aliasgharlou, Morteza Bahram, Pezhman Zolfaghari, Naiemeh Mohseni
Turkish Journal of Chemistry
This study aimed to propose a mathematical method to investigate and optimize the simultaneous elimination process of multiple organic pollutants using the Fenton process. Hence, the treatment of rhodamine B (RB) and acid red 14 (AR14) dyes in their binary solution was studied. Multivariate curve resolution alternating least square (MCR-ALS), a novel chemometric method, was applied along with correlation constraints to resolute the UV-Vis spectrophotometric data, enabling quantification of investigated dyes despite a high spectral overlapping. Response surface methodology was adopted to assess the model and optimize individual and interactive effects of three independent factors (Fe$^{2+}$, H$_{2}$O$_{2}$ and initial pH) …
Effect Of Surfactant Types On Particle Size And Morphology Of Flame-Retardantzinc Borate Powder, Yeli̇z İpek
Effect Of Surfactant Types On Particle Size And Morphology Of Flame-Retardantzinc Borate Powder, Yeli̇z İpek
Turkish Journal of Chemistry
Zinc borate is a boron-containing chemical material that is used to increase the flame retardancy of polymeric materials, dyes, cables, fabrics, carpets, and the internal parts of automobiles and planes. Commercially used zinc borate, which has the formula of 2ZnO· 3B$_{2}$ O$_{3}$· 7H$_{2}$ O, has a particle size between 10 and 20 μm. However, recent studies have shown that nanosized flame retardants have more superior flame retardancy and less negative effects on mechanical properties than microsized flame retardants. Nanosized flame retardants disperse more homogeneously and even low quantities are sufficient to provide high flame resistance. In this study, nano zinc …
Fabrication And Biocompatibility Assessment Of Polypyrrole/Cobalt(Ii) Metal-Organic Frameworks Nanocomposite, Mehrnaz Mehrabani, Zeinab Ansari Asl, Farzaneh Rostamzadeh, Saeideh Jafarinejad Farsangi, Mahnaz Sadat Hashemi, Mozhgan Sheikholeslami, Zeinab Neisi
Fabrication And Biocompatibility Assessment Of Polypyrrole/Cobalt(Ii) Metal-Organic Frameworks Nanocomposite, Mehrnaz Mehrabani, Zeinab Ansari Asl, Farzaneh Rostamzadeh, Saeideh Jafarinejad Farsangi, Mahnaz Sadat Hashemi, Mozhgan Sheikholeslami, Zeinab Neisi
Turkish Journal of Chemistry
Nowadays, metal-organic frameworks (MOFs) have emerged as promising tools for different biological applications and therefore, efforts are ongoing to develop more biocompatible MOFs-based nanocomposites. We aimed to fabricate some new conductive nanocomposites of polypyrrole and cobalt-MOF with different weight percentages (PPy/x%Co-MOF)usingthesolutionmixingmethodandcharacterizethemthroughFT-IR(Fourier-transforminfrared), PXRD (powder X-ray diffraction), SEM (scanning electron microscope), and TEM (transmission electron microscope) techniques. The biocompatibility of nanocomposites was assessed by haemolytic, cytotoxic, and quantitative reverse transcription PCR (qRT-PCR) assays. FT-IR and PXRD results revealed that nanocomposites consisted of pure MOFs and PPy. Moreover, SEM results indicated their spherical morphology along with an average diameter of 190 nm. (3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium …
Hosphorus-Nitrogen Compounds (Part 51): The Relationship Between Spectroscopic And Crystallographic Data Of Mono- And Di-Spirocyclophosphazene Derivatives With 4-Fluoro/Nitrophenylmethyl Pendant Arm/Arms, Aytuğ Okumuş, Gamze Elmas, Nuran Asmafi̇li̇z, Selen Bi̇lge Koçak, Zeynel Kiliç
Hosphorus-Nitrogen Compounds (Part 51): The Relationship Between Spectroscopic And Crystallographic Data Of Mono- And Di-Spirocyclophosphazene Derivatives With 4-Fluoro/Nitrophenylmethyl Pendant Arm/Arms, Aytuğ Okumuş, Gamze Elmas, Nuran Asmafi̇li̇z, Selen Bi̇lge Koçak, Zeynel Kiliç
Turkish Journal of Chemistry
A great wealth of structural information about phosphazenes can be gleaned from the combined spectroscopic and crystallographic data. When data from $^{31}$P NMR spectroscopy and X-ray crystallography are put together like pieces in a puzzle, a number of correlations can be obtained for phosphazene derivatives. A systematic study concerning the correlations among the structural parameters (e.g., $^{31}$P NMR data, endocyclic/exocyclic NPN bond angles and bond lengths) revealed some characteristics of mono- and di-spirocyclophosphazene derivatives bearing~4-fluoro/nitrophenylmethyl pendant arm/arms. These correlations include the relationship between the $\delta $P$_{spiro}$ shifts, the values of electron density transfer parameters $\Delta $(P--N), and the endocyclic and …
Allylphenoxypiperidinium Halides As Corrosion Inhibitors Of Carbon Steel And Biocides, Gunay Mehdiyeva Muzakir, Musa Bairamov Rza, Shahnaz Hosseinzadeh Bahador, Gulnara Hasanova Musa
Allylphenoxypiperidinium Halides As Corrosion Inhibitors Of Carbon Steel And Biocides, Gunay Mehdiyeva Muzakir, Musa Bairamov Rza, Shahnaz Hosseinzadeh Bahador, Gulnara Hasanova Musa
Turkish Journal of Chemistry
A series of 1-(4-(2-allylphenoxy)butyl)piperidin-1-ium halides (4a-d) was synthesized and characterized via spectroscopic methods (FTIR, $^{1}$H NMR). The corrosion inhibition of the synthesized halides on carbon steel in water-salt-hydrocarbon environment, saturated with H$_{2}$S, was investigated. For this purpose, a series of techniques such as gravimetric measurement, potentiodynamic polarisation, and scanning electron microscope (SEM) were used and some thermodynamic parameters of corrosion process ($\Delta G_{ads.}$, $\Delta H^{0}_{ads.}$, $\Delta S^{0}_{ads.})$ were evaluated. The steel surface was checked by SEM, and the steel surface showed good surface coverage. The results showed that the synthesized compounds at the concentrations 125, 150 mg x L$^{-1}$ have …
Synthesis And Liquid Crystalline Properties Of New Triazine-Based $\Pi $-Conjugated Macromolecules With Chiral Side Groups, Ni̇hat Akkurt, Mohammed Hadi Ali Al-Jumaili, Hale Ocak, Fati̇h Çakar, Lokman Torun
Synthesis And Liquid Crystalline Properties Of New Triazine-Based $\Pi $-Conjugated Macromolecules With Chiral Side Groups, Ni̇hat Akkurt, Mohammed Hadi Ali Al-Jumaili, Hale Ocak, Fati̇h Çakar, Lokman Torun
Turkish Journal of Chemistry
In this study, we reported the synthesis of a new tribranched macromolecule liquid crystal with triazine in the centre. The central triazine core is bonded via sequences of Sonigashira coupling to 3 triazine unites through acetylenic bridges. The triazines at the periphery are substituted with 2 chiral citronellyloxy side groups. The salt of the resulting star-shaped macromolecule, which was oily at room temperature, with 4-dodecyloxybenzoic acid at 1:1 ratio exhibited a Smectic C (SmC) mesophase. The liquid crystalline properties of organic salt were investigated using DSC (differential scanning calorimetry) and POM (polarizing optical microscopy).
Synthesis, Characterization And Crystal Structures Of Platinum(Ii) Saccharinate Complexes With 1,5-Cyclooctadiene, Ceyda İçsel
Synthesis, Characterization And Crystal Structures Of Platinum(Ii) Saccharinate Complexes With 1,5-Cyclooctadiene, Ceyda İçsel
Turkish Journal of Chemistry
Two new platinum(II) complexes, namely [PtCl(sac)(COD)] (1) and [Pt(sac)$_{2}$(COD)] (2) (sac $=$ saccharinate and COD $=$ 1,5-cyclooctadiene), were synthesized and characterized by elemental analysis, IR, NMR, ESI-MS spectroscopic and thermal analysis (TG/DTA) methods. The platinum(II) complexes were prepared from the reaction of [PtCl$_{2}$(COD)] with Na(sac) • 2H$_{2}$O. The addition of the sac ligand resulted in the replacement of 1 and 2 chlorido ligands in [PtCl$_{2}$(COD)] to yield 1 and 2, respectively. The structures of the complexes were determined by single crystal X-ray diffraction and showed a distorted square planar coordination geometry around platinum(II). COD acted as a $\pi $-donor ligand, …
Preparation Of Rapid (Chain-Stopped) Alkyds By Incorporation Of Gum Rosin And Investigation Of Coating Properties, Cemi̇l Dizman, Eli̇f Ozman
Preparation Of Rapid (Chain-Stopped) Alkyds By Incorporation Of Gum Rosin And Investigation Of Coating Properties, Cemi̇l Dizman, Eli̇f Ozman
Turkish Journal of Chemistry
In this study, the synthesis, characterization, and properties of a short oil length chain--stopped(rapid) alkyd resin is investigated. Gum rosin modified alkyd resin (RA-GR) was prepared using soybean oil, phthalic anhydride, glycerin and gum rosin acid. An alkyd modified with benzoic acid (RA-BA) was also prepared for comparison. FTIR analyses and GPC measurements of the alkyds were used for characterization. Other properties such as the viscosity, acid value, and solid content of the final resins were determined. Separately, the synthesized resins were used in paint formulations without any changes in other parameters such as filler, airdrying agents, solvents, etc. Paints …
A Road Map To Assess Critical Materials Content In Boron Industrial Wastes Usingsustainable Micro-X-Ray Fluorescence And Total Reflection X-Ray Fluorescenceinstrumentation, İbrahi̇m Kula, Christian Gutsche, Yunus Erdoğan, Andreas Fittschen, Ursula Elisabeth Adriane Fittschen
A Road Map To Assess Critical Materials Content In Boron Industrial Wastes Usingsustainable Micro-X-Ray Fluorescence And Total Reflection X-Ray Fluorescenceinstrumentation, İbrahi̇m Kula, Christian Gutsche, Yunus Erdoğan, Andreas Fittschen, Ursula Elisabeth Adriane Fittschen
Turkish Journal of Chemistry
Turkey is the leading country in the world in terms of boron production and sale. Increasing boron production goes along with an increasing generation of boron wastes. The pollution of the soil and the air around the waste piles, as well as the occupation of several square kilometers of ground, are major environmental problems. It is, therefore, very important to make use of the wastes to both protect the environment and create revenue. This work presenteda road map for fast screening of boron waste for critical elements followed by determination of the elements using small footprint low power instrumentation. The …
Characterization And Kinetics Analysis Of The Thermal Decomposition Of The Humic Substance From Hazelnut Husk, Fatma Kara, Duygu Adigüzel, Ufuk Atmaca, Murat Çeli̇k, Jale Nakti̇yok
Characterization And Kinetics Analysis Of The Thermal Decomposition Of The Humic Substance From Hazelnut Husk, Fatma Kara, Duygu Adigüzel, Ufuk Atmaca, Murat Çeli̇k, Jale Nakti̇yok
Turkish Journal of Chemistry
A humic substance was obtained from hazelnut husk using an alkali extraction. The chemical and morphological structure of the humic matter was characterized via elemental analysis, Fourier transform infrared spectrometry (FTIR), nuclear magnetic resonance, Brunauer-Emmet-Teller (BET) analysis, scanning electron microscopy (SEM), and thermogravimetric-FTIR (TG-FTIR). In addition, thermal analysis measurements TG analysis-differential thermogravimetry/differential scanning calorimetry (TGA-DTG/ DSC) were performed under dynamic air conditions to better determine the origin, physical and chemical structure, and decomposition process of the humic matter. The Kissinger-Akahira-Sunose (KAS) and Flynn-Wall-Ozawa (FWO) methods were used to calculate the kinetic parameters of the high-temperature decomposition process. It was observed …
Multiwall Carbon Nanotube-Supported Molybdenum Catalysts For Ammonia Decomposition Reaction Under Microwave Effect, Meli̇h Güler, Di̇lek Varişli
Multiwall Carbon Nanotube-Supported Molybdenum Catalysts For Ammonia Decomposition Reaction Under Microwave Effect, Meli̇h Güler, Di̇lek Varişli
Turkish Journal of Chemistry
In this study, microwave-assisted ammonia decomposition reaction was investigated over molybdenum incorporated catalysts. Due to the selective, volumetric, and noncontact heating properties of the microwave system, higher conversion values could be achieved at relatively lower reaction temperatures, which is important for on-site COx-free hydrogen production. Multiwall carbon nanotube-supported molybdenum catalysts were prepared following the impregnation procedure with different metal loading (3.5%-12.5% wt%), and inductively coupled plasma, nitrogen physisorption, X-ray diffraction, and transmission electron microscopic techniques were employed to characterize the fresh and used samples. Reaction experiments were performed under the flow of pure ammonia with a gas hourly space velocity …
Box-Behnken Design For Removal Of Uranium(Vi) From Aqueous Solution Using Poly(Ethylene Glycol) Based Dicationic Ionic Liquid Impregnated Chitosan, Süleyman İnan, Taşkin Mumcu, Serap Seyhan Bozkurt
Box-Behnken Design For Removal Of Uranium(Vi) From Aqueous Solution Using Poly(Ethylene Glycol) Based Dicationic Ionic Liquid Impregnated Chitosan, Süleyman İnan, Taşkin Mumcu, Serap Seyhan Bozkurt
Turkish Journal of Chemistry
Poly(ethylene glycol) bis(methylimidazolium) di[bis(trifluoromethylsulfonyl)imide] was synthesized as an ionic liquid and impregnated onto chitosan. The removal of uranium(VI) ions from aqueous solution was investigated with batch sorption tests using ionic liquid impregnated chitosan. Response surface methodology based on 3 level Box-Behnken design was applied to analyze the effect of initial pH (4-6), initial concentration (20-60 mg L$^{-1})$, contact time (15-105 min), and temperature (30-50 $^{\circ}$C C) on the uptake capacity of uranium(VI). Main effect of initial concentration, quadratic effect of contact time, and dual effect of initial pH and contact time were found statistically significant based on analysis of variance …
New Protocols For The Synthesis Of 5-Amino-7-(4-Phenyl)-4,7-Dihydro-[1,2,4]Triazolo[1,5-A]Pyrimidine-6-Carboxylate Esters Using An Efficient Additive, Nader Ghaffari Khaligh, Taraneh Mihankah, Salam Titinchi, Zohreh Shahnavaz, Mohd Rafie Johan
New Protocols For The Synthesis Of 5-Amino-7-(4-Phenyl)-4,7-Dihydro-[1,2,4]Triazolo[1,5-A]Pyrimidine-6-Carboxylate Esters Using An Efficient Additive, Nader Ghaffari Khaligh, Taraneh Mihankah, Salam Titinchi, Zohreh Shahnavaz, Mohd Rafie Johan
Turkish Journal of Chemistry
This work introduces a new additive named 4,4'-trimethylenedipiperidine for the practical and ecofriendly preparation of ethyl 5-amino-7-(4-phenyl)-4,7-dihydro-[1,2,4]triazolo[1,5-$a$]pyrimidine-6-carboxylate derivatives. This chemical is commercially available and easy to handle. It also possesses a low melting point and a broad liquid range temperature, high thermal stability, and good solubility in water. Based on green chemistry principles, the reaction was performed in a) a mixture of green solvents i.e. water and ethanol (1:1 v/v) at reflux temperature, and b) the additive was liquefied at 65 $^{\circ}$C and the reaction was conducted in the liquid state of the additive. High yields of the desired triazolo-pyrimidines …
A Novel Proton-Exchange Porous Silicon Membrane Production Method For \Textmu Dmfcs, Meltem Gör Bölen, Tevhi̇t Karacali
A Novel Proton-Exchange Porous Silicon Membrane Production Method For \Textmu Dmfcs, Meltem Gör Bölen, Tevhi̇t Karacali
Turkish Journal of Chemistry
This study introduces a new production method to use as a porous silicon-based proton exchange membrane for μDMFCs. In this respect, EIS, fuel crossover test, and fuel cell performance test at the μDMFC sample cell are performed at room temperature on a porous silicon-based membrane that was produced for passive mode μDMFC as a proton exchange membrane. The reason for performing the fuel crossover test is to ensure the silicon opened pores along the silicon wafer and to examine the fuel permeability of the membrane. The fuel crossover test shows that the fuel cell provides energy for about 60 min …
Water Management Improvement In Pem Fuel Cells Via Addition Of Pdms Or Aptespolymers To The Catalyst Layer, Hande Ungan, Ayşe Bayrakçeken Yurtcan
Water Management Improvement In Pem Fuel Cells Via Addition Of Pdms Or Aptespolymers To The Catalyst Layer, Hande Ungan, Ayşe Bayrakçeken Yurtcan
Turkish Journal of Chemistry
Water management is one of the obstacles in the development and commercialization of proton exchange membrane fuel cells (PEMFCs). Sufficient humidification of the membrane directly affects the PEM fuel cell performance. Therefore, 2 different hydrophobic polymers, polydimethylsiloxane (PDMS) and (3-Aminopropyl) triethoxysilane (APTES), were tested at different percentages (5, 10, and 20 wt.%) in the catalyst layer. The solution was loaded onto the surface of a 25 BC gas diffusion layer (GDL) via the spraying method. The performance of the obtained fuel cells was compared with the performance of the commercial catalyst. Characterizations of each surface, including different amounts of PDMS …
Preparation Of Different Thin Film Catalysts By Direct Current Magnetron Sputtering Forhydrogen Generation, Gamze Bozkurt, Abdulkadi̇r Özer, Ayşe Bayrakçeken Yurtcan
Preparation Of Different Thin Film Catalysts By Direct Current Magnetron Sputtering Forhydrogen Generation, Gamze Bozkurt, Abdulkadi̇r Özer, Ayşe Bayrakçeken Yurtcan
Turkish Journal of Chemistry
In this study, thin films of Co, Ni, Pd, and Pt were prepared on Co$_{3}$O$_{4}$ support material in pellet form using the direct current (DC) magnetron sputtering method for use as catalysts for hydrogen generation from NaBH4.Characterization of the catalysts was carried out using X-ray diffraction (XRD), scanning electronic microscopy (SEM), and X-ray photoelectron spectroscopy (XPS). According to cross-sectional SEM images, catalyst thicknesses were observed in the range of approximately 115.3-495.8 nm. The particle sizes were approximately 25.0, 21.4, 33.9, and 9.5 nm for Ni-Co$_{3}$O$_{4}$, Co-Co$_{3}$O$_{4}$, Pd-Co$_{3}$O$_{4}$, and Pt-Co$_{3}$O$_{4}$ catalysts, respectively. The increase in NaOH initial concentration provides an increase …
Effect Of Ph On Lipid Oxidation Of Red Onion Skin Extracts Treated With Washed Tilapia (Oreochromis Niloticus) Muscle Model Systems, Senem Güner, Yavuz Yağiz, Zeynal Topalcengi̇z, Hordur G. Kristinsson, George Baker, Paul Sarnoski, Bruce A. Welt, Amarat Simonne, Maurice M. Marshall
Effect Of Ph On Lipid Oxidation Of Red Onion Skin Extracts Treated With Washed Tilapia (Oreochromis Niloticus) Muscle Model Systems, Senem Güner, Yavuz Yağiz, Zeynal Topalcengi̇z, Hordur G. Kristinsson, George Baker, Paul Sarnoski, Bruce A. Welt, Amarat Simonne, Maurice M. Marshall
Turkish Journal of Chemistry
The aim of the study was to investigate the effect of pH on the lipid oxidation of red onion skin extracts (ROSEs) treated with washed tilapia muscle model systems (WTMS). Minced and buffered washed samples were prepared at pH 6.3 and 6.8. The WTMS were treated with2 different concentrations of red onion skin prior to storage for 5 days. Lipid oxidation was investigated via peroxide values (PVs), thiobarbituric acid reactive substances (TBARS), and the formation of volatile compounds. Fatty acid profiles of the samples were also identified. The ROSEs were able to significantly suppress the PV (~71%) and TBARS (~42%) …
Synthesis And Electrochemical Properties Of Copper(Ii), Manganese(Iii) Phthalocyanines Bearing Chalcone Groups At Peripheral Or Nonperipheral Positions, Hüseyi̇n Baş, Nuran Kahri̇man, Zekeri̇ya Biyiklioğlu
Synthesis And Electrochemical Properties Of Copper(Ii), Manganese(Iii) Phthalocyanines Bearing Chalcone Groups At Peripheral Or Nonperipheral Positions, Hüseyi̇n Baş, Nuran Kahri̇man, Zekeri̇ya Biyiklioğlu
Turkish Journal of Chemistry
In this study, new chalcone compound 1, new phthalonitrile derivatives 2 and 3, new copper(II), manganese(III) phthalocyanines bearing chalcone groups at peripheral or nonperipheral positions were synthesized. Electrochemistry of tetra-(4- {(2E)-3-[2-fluoro-4-(trifluoromethyl)phenyl]prop-2-enoyl}phenoxy) substituted Co(II)Pc and Mn(III)Pcs were studied with cyclic voltammetry (CV) to determine the redox properties of the phthalocyanines. According to the results, while the CuPcs 2a and 3a showed two Pc based reduction reactions and one Pc based oxidation reaction, MnPcs 2b and 3b gave two metal-based reduction reactions. All the redox processes are shifted toward positive potentials as a result of the increased electron-withdrawing ability of the trifluoromethyl …
Comparison Of Antioxidant Capacities And Antioxidant Components Of Commercial Bitter Melon (Momordica Charantia L.) Products, Esi̇n Akyüz, Sercan Türkoğlu, Kevser Sözgen Başkan, Esma Tütem, Mustafa Reşat Apak
Comparison Of Antioxidant Capacities And Antioxidant Components Of Commercial Bitter Melon (Momordica Charantia L.) Products, Esi̇n Akyüz, Sercan Türkoğlu, Kevser Sözgen Başkan, Esma Tütem, Mustafa Reşat Apak
Turkish Journal of Chemistry
In this study, the total phenolic contents and total antioxidant capacities of some commercial bitter melon products (powder, packaged powder, capsule, paste in olive oil), and of unripe and ripe fruits were determined by spectrophotometric and chromatographic methods. The total antioxidant capacities of unripe and ripe bitter melon samples, determined by using the CUPRAC (cupric reducing antioxidant capacity assay) and ABTS (2,2'-Azinobis-(3-Ethylbenzthiazolin-6-Sulfonic Acid)/HRP (horseradish peroxidase) methods, were 42.5 and 36.3 μmol TRE (Trolox equivalent) g-1, and 8.7 and 7.0 μmol TRE g-1, respectively. The TAC (total antioxidant capacity) order of the studied samples using the same 2 methods were determined …
Pyrene-Bodipy-Substituted Novel Water-Soluble Cyclotriphosphazenes: Synthesis,Characterization, And Photophysical Properties, Seda Çeti̇ndere, Serkan Yeşi̇lot, Adem Kiliç
Pyrene-Bodipy-Substituted Novel Water-Soluble Cyclotriphosphazenes: Synthesis,Characterization, And Photophysical Properties, Seda Çeti̇ndere, Serkan Yeşi̇lot, Adem Kiliç
Turkish Journal of Chemistry
In the present work, pyrene-boron-dipyrromethene (BODIPY)-substituted novel water-soluble cyclotriphosphazene derivatives (6 and 7) were synthesized by click reactions between a cyclotriphosphazene derivative with a hydrophilic glycol side group (2) and BODIPYs (4 and 5). All of the new compounds (2, 6, and 7) were characterized by Fourier-transform infrared and nuclear magnetic resonance spectroscopy, as well as mass spectrometry and elemental analysis. The photophysical properties of the BODIPY-substituted cyclotriphosphazenes (6 and 7) were investigated by UV-Vis and fluorescence emission spectroscopy in water and water/solvent mixtures. It was found that the target compounds were soluble in water and could be potential candidates …