Scalable Activated Carbon/Graphene Based Supercapacitors With Improved Capacitanceretention At High Current Densities,
2021
TÜBİTAK
Scalable Activated Carbon/Graphene Based Supercapacitors With Improved Capacitanceretention At High Current Densities, İffet Işil Gürten
Turkish Journal of Chemistry
Scalable, highly stable supercapacitor electrodes were developed from the mixture of a tea factory waste based activated carbon (AC) and a low-cost electrochemical exfoliated graphene (EEG). The hybrid electrodes showed notably enhanced stability at high current densities. The AC sample was prepared by chemical method and exposed to a further heat treatment to enhance electrochemical performance. Graphene used in the preparation of hybrid electrodes was obtained by direct electrochemical exfoliation of graphite in an aqueous solution. Detailed structural characterization of AC, EEG, and hybrid material was performed. The original electrochemical performances of AC and EEG were examined in button size …
Phenolic Compounds, Essential Oil Composition, And Antioxidant Activity Of Angelica Pur-Purascens (Avé-Lall.) Gill,
2021
TÜBİTAK
Phenolic Compounds, Essential Oil Composition, And Antioxidant Activity Of Angelica Pur-Purascens (Avé-Lall.) Gill, Semra Alkan Türkuçar, Ayça Aktaş Karaçeli̇k, Mustafa Karaköse
Turkish Journal of Chemistry
In this study, methanol extracts (MEs) and essential oil (EO) of Angelica purpurascens (Avé-Lall.) Gill obtained from different parts (root, stem, leaf, and seed) were evaluated in terms of antioxidant activity, total phenolics, compositions of phenolic compound, and essential oil with the methods of 2,2-azino-bis(3ethylbenzo-thiazoline-6-sulfonic acid (ABTS•+), 2,2-diphenyl-1-picrylhydrazil (DPPH•) radical scavenging activities, and ferric reducing/antioxidant power (FRAP), the Folin?Ciocalteu, liquid chromatography- tandem mass spectrometry (LC-MS/MS), and gas chromatography-mass spectrometry (GC-MS), respectively. The root extract of A. Purpurascens exhibited the highest ABTS•+, DPPH•, and FRAP activities (IC50: 0.05 ± 0.0001 mg/mL, IC50: 0.06 ± 0.002 mg/mL, 821.04 ± 15.96 μM TEAC …
Synthesis Of Ni/Al2o3 Catalysts Via Alkaline Polyol Method And Hydrazine Reduction Method For The Partial Oxidation Of Methane,
2021
TÜBİTAK
Synthesis Of Ni/Al2o3 Catalysts Via Alkaline Polyol Method And Hydrazine Reduction Method For The Partial Oxidation Of Methane, Ezgi̇ Bayrakdar Ateş, Tuba Gürkaynak Altinçeki̇ç, Mehmet Ali̇ Faruk Öksüzömer
Turkish Journal of Chemistry
Nickel catalysts supported on γ-Al2O3 were synthesized in the presence of polyvinylpyrrolidone (PVP) using both alkaline polyol method and hydrazine reduction method while fixing the weight ratio of [(PVP)]/[Ni(CH3COO)2·4H2O] at 2. The effects of hydrazine [N2H5 OH]/[Ni] and [NaOH]/[Ni] molar ratios on the structural properties of the catalysts were characterized by transmission electron microscopy (HRTEM) and by X-ray diffraction (XRD). The average of monodispersed Ni nanoparticles ranged between 8.0 and 13.0 nm. The catalytic tests were performed for the partial oxidation of methane in the temperature range of 600-800 °C under a flow rate of 157,500 L kg-1 hr-1 with …
Novel Mixed Ligand Coordination Compounds Of Some Rare Earth Metal Cations Containing Acesulfamato/N,N-Diethylnicotinamide,
2021
TÜBİTAK
Novel Mixed Ligand Coordination Compounds Of Some Rare Earth Metal Cations Containing Acesulfamato/N,N-Diethylnicotinamide, Leri̇man Zeybel, Dursun Ali̇ Köse
Turkish Journal of Chemistry
The mixed ligand coordination compounds containing acesulfamato and N,N-diethylnicotinamide biomolecules of some rare earth metal cations (Eu3+, Tb3+, Ho3+, Er3+ and Yb3+) were synthesized, and their structural properties were investigated. Possible structural formulas have been proposed by determining the chemical composition of molecules (elemental analysis), binding properties (infrared spectroscopy, mass analysis, solid-state UV-vis spectroscopy), thermal degradation properties (TGA / DTA curves). Based on the data collected, it is suggested that rare earth metal cations with a 3+ oxidation state have sextet coordination. The geometries of the structures were thought to be distorted octahedral. The charge balance of the coordination sphere …
Binding Of Permanganate Anion To Pentaammineazidocobalt(Iii) Cation In Solution And Solid Phases: Synthesis, Characterization, X-Ray Structure, And Genotoxic Effects Of [Co(Nh3)5n3](Mno4)2•H2o, Ritu Bala, Jinkwon Kim, Vinit Prakash
Turkish Journal of Chemistry
A pentaammineazidocobalt(III) complex, [Co(NH3)5N3](MnO4)2XH2O has been synthesized by an one-pot synthesis method. It was characterized by studies such as infrared (IR) and UV-visible spectroscopy. The single crystal X-ray structure analysis revealed that the title complex crystallizes in space group Cc. The cobalt center is six coordinated with slightly octahedral geometry. The supramolecular architecture is also formed by intermolecular N-H…O (anion and H2O) and Mn-O…O-H hydrogen bonds. The binding property of the cation, [Co(NH3)5N3]2+ with the anion, MnO4- has also been determined (in solution phase) with the help of UV-visible spectroscopic titrations. Further, the genotoxic effects of KMnO4, [Co(NH3)5N3]Cl2 and [Co(NH3)5N3](MnO4)2XH2O …
Evaluation Of Quercetin As A Potential Β-Lactamase Ctx-M-15 Inhibitor Via The Molecular Docking, Dynamics Simulations, And Mmgbsa, Emrah Sariyer, Ayşegül Saral
Turkish Journal of Chemistry
Antimicrobial resistance (AMR) threatens millions of people around the world and has been declared a global risk by the World Economic Forum. One of the important AMR mechanisms in Enterobacteriaceae is the production of extended-spectrum β-lactamases. The most common ESBL, CTX-M β-lactamases, is spread to the world by CTX-M-15 and CTX-M-14. Sulbactam, clavu-lanic acid, and tazobactam are first-generation β-lactamase inhibitors and avibactam is a new non-β-lactam β-lactamase inhibitor. We studied that avibactam, sulbactam, clavulanic acid, tazobactam, and quercetin natural flavonoids were docked to target protein CTX-M-15. Subsequently, the complexes were simulated using the molecular dynamics simulations method during 100 ns …
Impact Of Graphitic Carbon Nitrides Synthesized From Different Precursors On Schottky Junction Characteristics,
2021
TÜBİTAK
Impact Of Graphitic Carbon Nitrides Synthesized From Different Precursors On Schottky Junction Characteristics, Orhan Altan
Turkish Journal of Chemistry
Graphitic carbon nitride (g-CN) has gained wide interest in many areas, such as energy and the environmental remediation as a layered polymeric semiconductor that allows the formation of catalytically active Schottky junctions due to its proper electronic band structure. Interestingly, although it is known that the precursors used in the synthesis, can influence the properties of the g-CN, no detailed study on these effects on Schottky junctions could be found in the literature. In this research, the effects of g-CNs synthesized by thermal polycondensation of different precursors on the photocatalytic efficiency of Schottky junctions were investigated. For this purpose, urea, …
Feature Of Catalysis On Bimetallic Alloys Zr With V, Mo, And Fe In The Reaction Of Methanol Oxidation,
2021
TÜBİTAK
Feature Of Catalysis On Bimetallic Alloys Zr With V, Mo, And Fe In The Reaction Of Methanol Oxidation, Arif Efendi, Lala Magerramova, Adila Aliyeva, Lyudmila Kozharova, Elmir Babayev
Turkish Journal of Chemistry
Catalytic behaviors of bimetallic catalysts-alloys of zirconium with vanadium, molybdenum, and iron was investigated in the oxidative dehydrogenation of methanol. The conditions for the formation of the catalyst's active surface were revealed. The conversion of methanol into formaldehyde, dimethyl ether, and dimethoxymethane on bimetallic catalysts was studied. The characterization of catalysts was performed by XRD, XPS, and SEM. It was shown that the activity of samples increases after O2 + H2 treatment and was associated with segregation of the active components of alloys (V, Mo) on the surface of catalysts and realization of their optimal oxidation state under catalysis conditions.
Green Biosynthesis, Characterization, And Cytotoxic Effect Of Magnetic Iron Nanoparticles Using Brassica Oleracea Var Capitata Sub Var Rubra (Red Cabbage) Aqueous Peel Extract, Ömer Erdoğan, Sali̇h Paşa, Gülen Meli̇ke Demi̇rbolat, Özge Çevi̇k
Turkish Journal of Chemistry
The green method of nanoparticle synthesis, which is an environment and living-friendly method, is an updated subject that has appeared as an alternative to conventional methods such as physical and chemical synthesis. In this presented study, the green synthesis of magnetic iron oxide nanoparticles (IONPs) from iron (III) chloride by using Brassica oleracea var. capitata sub.var. rubra aqueous peel extract has been reported. The prepared IONPs were characterized with fourier-transform infrared spectroscopy (FT-IR), ultraviolet-visible spectroscopy (UV-VIS), zeta potential, scanning electron microscopy (SEM), and energy-dispersive X-ray spectroscopy (EDX). The cytotoxic effects of IONPs on MCF-7 breast cancer cell line were studied …
Synthesis And Characterization Of Benzodioxinone Mono-Telechelics And Their Use In Block Copolymerization,
2021
TÜBİTAK
Synthesis And Characterization Of Benzodioxinone Mono-Telechelics And Their Use In Block Copolymerization, Cumali̇ Çeli̇k
Turkish Journal of Chemistry
Poly(methyl methacrylate) (PMMA) and poly(ethylene glycol) methyl ether (mPEG)-based monotelechelics were quantitatively prepared by copper (I)-catalyzed azide/alkyne cycloaddition (CuAAC) click reactions using azido-terminated polymers and alkyne functional benzodioxinones. The monotelechelic containing dimethyl moities (2,2-dimethyl-5-(prop-2-yn-1-yloxy)-4H-benzo[d][1,3]dioxin-4-one) was heat-sensitive, whereas the monotelechelic containing diphenyl moieties (2,2-diphenyl-5-(prop-2-yn-1-yloxy)-4H-benzo[d][1,3]dioxin-4-one) was UV light sensitive. Based on the FT-IR, 1 H-NMR, and GPC investigations, the CuAAC click reactions enable the quantitative syntheses of monotelechelics under mild conditions. Moreover, the photosensitive mPEG-based monotelechelic was further utilized for the block copolymer synthesis upon UV-light irradiation. The photoinduced acylation of mPEG monotelechelic consist of (2,2-diphenyl-5-(prop-2-yn-1-yloxy)-4H-benzo[d][1,3]dioxin-4-one) in the presence of hydroxy-terminated poly(epsilon …
Turkish Perlite Supported Nickel Oxide As The Heterogeneous Acid Catalyst For A Series Of Claisen?Schmidt Condensation Reactions, Sakshi Kabra Malpani, Deepti Goyal, Stuti Katara, Ashu Rani
Turkish Journal of Chemistry
Potentially active and eco-friendly solid acid catalysts have been synthesized by loading different weight percentages (10, 15, and 50) of nickel oxide on thermally activated Turkish perlite through the deposition-precipitation method. Structural features of prepared catalysts were analyzed using BET surface area analysis, X-ray diffraction, scanning electron microscope (SEM), SEM-EDX, transmission electron microscopy (TEM), Fourier-transform infrared (FT-IR), pyridine adsorbed FT-IR, UV-Vis diffuse reflectance spectroscopy (DRS), and thermogravimetric analysis (TGA) techniques. Pyridine adsorbed FT-IR analysis confirmed the presence of the optimum amount of Bronsted acidic sites in a catalyst having 15 wt. % loading of nickel oxide, which was tested for …
Remarkable Bismuth-Gold Alloy Decorated On Mwcnt For Glucose Electrooxidation: The Effect Of Bismuth Promotion And Optimization Via Response Surface Methodology, Ömer Faruk Er, Berdan Ulaş, Hi̇lal Demi̇r Kivrak
Turkish Journal of Chemistry
In this study, the carbon nanotube supported gold, bismuth, and gold-bismuth (Au/MWCNT, Bi/MWCNT, and Au-Bi/ MWCNT) nanocatalysts were prepared with NaBH4 reduction method at varying molar atomic ratio for glucose electrooxidation (GAEO). The synthesized nanocatalysts at different Au: Bi atomic ratios are characterized via x-ray diffraction (XRD), transmission electron microscopy (TEM), and N2 adsorption-desorption. For the performance of AuBi/MWCNT for GAEO, electrochemical measurements are performed by using different electrochemical techniques namely cyclic voltammetry (CV), linear sweep voltammetry (LSV), chronoamperometry (CA), and electrochemical impedance spectroscopy (EIS). Monometallic Au/MWCNT exhibits higher activity than Bi/MWCNT with 256.57 mA/mg (0.936 mA/cm2) current density. According …
Adsorptive Performance Of Mwcnts For Simultaneous Cationic And Anionic Dyes Removal; Kinetics, Thermodynamics, And Isotherm Study, Zaheer Aslam, Irfan Yousaf, Abdul Zahir, Adnan Akhtar
Turkish Journal of Chemistry
Disposal of contaminated wastewater causes many serious problems especially when it gets mixed with the ground and seawater. It is, therefore, important to apply any remedial action to eradicate dangerous pollutants from the aqueous effluents and to avoid exposure of this wastewater to aquatic life. The research results discussed herein deal with the removal of Rhodamine B (RhB) and Congo Red (CR) dye from wastewater by using multi-walled carbon nanotubes (MWCNTs) as an adsorbent. Different factors like solid dosage, initial pH and concentration, time, and temperature were studied to understand the behavior and mechanism of adsorption. The maximum adsorption capacity …
Preconcentration Of Rifampicin Prior To Its Efficient Spectroscopic Determination In The Wastewater Samples Based On A Nonionic Surfactant, Afaq Ullah Khan, Faheem Shah, Rafaqat Ali Khan, Bushra Ismail, Asad Muhammad Khan, Haji Muhammad
Turkish Journal of Chemistry
Every year, tuberculosis affects the lungs of millions of people and rifampicin is the commonly used medicine for its treatment due to its antibiotic nature. The frequent use of rifampicin may lead to its increased concentration in the water resources. This research work is focused on the cloud point extraction (CPE) procedure for the preconcentration of rifampicin prior to its determination in water. The UV/vis spectrophotometric method was adapted for the measurement of rifampicin content after the phase separation. Triton-X 100 was used as the nonionic surfactant which contains hydrophilic polyethylene chain feasible for the extraction of analyte. Various analytical …
Fabrication And Characterization Of Enhanced Hydrazine Electrochemical Sensor Based On Gold Nanoparticles Decorated On The Vanadium Oxide, Ruthenium Oxide Nanomaterials, And Carbon Nanotubes Composites, Si̇bel Karaca, Süleyman Koçak
Turkish Journal of Chemistry
This work describes the synthesis of mixed oxide film of vanadium and ruthenium by pulsed deposition technique on multiwall carbon nanotubes and the decoration of gold nanoparticles on the mixed film. A ternary electrocatalyst has been developed for the electrochemical oxidation of hydrazine by combining two metal oxide mixtures with Au nanoparticles. Surface morphology and chemical composition of the electrode have been examined with SEM, EDX, HRTEM, EIS, and XRD. The peak current of hydrazine increased 9 times at the AuNPs/(VOx-RuOx)/CNT/GCE compared to the bare GCE, and the peak potential shifted to negative 848 mV. Linear sweep voltammetry (LSV) and …
Sensitive And Selective Determination Of Imidacloprid With Magnetic Molecularly Imprinted Polymer By Using Lc/Q-Tof/Ms,
2021
TÜBİTAK
Sensitive And Selective Determination Of Imidacloprid With Magnetic Molecularly Imprinted Polymer By Using Lc/Q-Tof/Ms, Rai̇f İlktaç, Zi̇nar Pinar Gümüş
Turkish Journal of Chemistry
In this paper, magnetic-molecularly imprinted polymer was used for the preconcentration of trace levels of imidacloprid in water and apple samples prior to liquid chromatography-quadrupole-time-of-flight mass spectrometric determination. The selectivity of the magnetic polymer was united with the sensitivity and the high resolving power of the chromatographic system. The developed method showed a linear range from 10.0 to 500.0 μg/L. The quantitative recoveries were obtained for water and apple samples in the range of 92.0%-99.0 %. The relative standard deviations of intra-day and inter-day tests were found to be in the range of 0.8%-1.2% and 1.2%-1.6 %, respectively. In addition, …
Supercritical Carbon Dioxide Extraction Of Usnea Longissima (L.) Ach.: Optimization By Box-Behnken Design (Bbd),
2021
TÜBİTAK
Supercritical Carbon Dioxide Extraction Of Usnea Longissima (L.) Ach.: Optimization By Box-Behnken Design (Bbd), Ceren Ati̇la Di̇nçer, Ceren Gökalp, Bengü Geti̇ren, Ati̇la Yildiz, Nuray Yildiz
Turkish Journal of Chemistry
Usnic acid (UA) was extracted from Usnea longissima (L.) Ach. in supercritical carbon dioxide (SC-CO2) medium. The selected process parameters were extraction temperature (35-45 °C), amount of co-solvent (0%-5%) and extraction time (5-9 h). These parameters were applied to Box-Behnken design (BBD) belonging to response surface methodology (RSM) to determine optimum process parameters for the highest amount of UA in the extract. g UA/100g lichen, extraction yield % and UA content values were calculated in the range of 0.045-0.317, 2.77-5.4 and 71%-82% in different experimental conditions, respectively. The optimum conditions were predicted as 42 °C, 4.3% (ethanol) and 7.48 h. …
Preparation And Characterization Of Templated Porous Carbons From Sucrose By One-Pot Method And Application As A Co2 Adsorbent,
2021
TÜBİTAK
Preparation And Characterization Of Templated Porous Carbons From Sucrose By One-Pot Method And Application As A Co2 Adsorbent, Meltem Gürbüz, Fatma Tümsek
Turkish Journal of Chemistry
The templated porous carbons were prepared from sucrose by one-pot method. In this method in which the pre-synthesis of the hard template is eliminated, the porous carbons were produced by organic-inorganic self-assembly of sucrose, tetraethyl ortosilicate (TEOS), Pluronic P123 and n-butanol in an acidic medium, and subsequent carbonization. The synthesis parameters such as sucrose amount, TEOS molar ratio and carbonization temperature were evaluated for describing their effects on the pore structures of the synthesized carbons. The prepared porous carbons were characterized by N2 adsorption, thermogravimetric analysis (TGA), Raman spectroscopy, X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), and transmission …
Structural And Adsorption Behaviour Of Zno/Aminated Swcnt-Cooh For Malachite Green Removal: Face-Centred Central Composite Design, Zeynep Ci̇ğeroğlu
Turkish Journal of Chemistry
In this study, an effective adsorbent was synthesized to remove malachite green (MG), which is one of the toxic dyes. Firstly, single walled carbon nanotube with carboxylated acid (SWCNT-COOH) was functionalized with diethylenetriamine and a new nanocomposite was obtained using nano zinc oxide (ZnO) powder. The effects of pH (3-7), the amount of adsorbent (5-15 mg) and the initial concentration (10-50 mg L-1) of the solution on the adsorption uptake were investigated. The optimal parameters that maximize the adsorption uptake according to the specified working range are found to be 4.63 for pH, 49.94 mg L-1 for initial concentration, 5.25 …
Catalytic, Theoretical, And Biological Investigation Of An Enzyme Mimic Model,
2021
TÜBİTAK
Catalytic, Theoretical, And Biological Investigation Of An Enzyme Mimic Model, Gülci̇han Gülseren
Turkish Journal of Chemistry
Artificial catalyst studies were always stayed at the kinetics investigation level, in this work bioactivity of designed catalyst were shown by the induction of biomineralization of the cells, indicating the possible use of enzyme mimics for biological applications. The development of artificial enzymes is a continuous quest for the development of tailored catalysts with improved activity and stability. Understanding the catalytic mechanism is a replaceable step for catalytic studies and artificial enzyme mimics provide an alternative way for catalysis and a better understanding of catalytic pathways at the same time. Here we designed an artificial catalyst model by decorating peptide …
