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Full-Text Articles in Physical Sciences and Mathematics

Tin-Sulfur Based Catalysts For Acetylene Hydrochlorination, Yibo Wu, Fuxiang Li, Xiaoqiang Luo, Gang Tian, Yunxiao Feng, Yongjun Han, Li Wang, Songmao Chu, Yunli Cao, Kesheng Cao, Xiaoming Hu, Xuejun Shi, Songtian Li, Guoxv He, Qingbin Li Jan 2021

Tin-Sulfur Based Catalysts For Acetylene Hydrochlorination, Yibo Wu, Fuxiang Li, Xiaoqiang Luo, Gang Tian, Yunxiao Feng, Yongjun Han, Li Wang, Songmao Chu, Yunli Cao, Kesheng Cao, Xiaoming Hu, Xuejun Shi, Songtian Li, Guoxv He, Qingbin Li

Turkish Journal of Chemistry

In the present work, tin-sulfur based catalysts were prepared using Na2SO3 and (CH3SO3)2Sn and were tested in acetylene hydrochlorination. Based on the analysis of experiments results, the acetylene conversion of (CH3SO3)2Sn/S@AC is still over 90% after a 50 h reaction, at the reaction conditions of T = 200 oC, VHCl/VC2H2 = 1.1:1.0 and C2H2-GSHV = 15 h-1. According to the results of X-ray photoelectron spectroscopy (XPS), HCl adsorption experiments, and acetylene temperature programmed desorption (C2H2-TPD), it is reasonable to conclude that the interaction between Sn and S not only can retard the oxidation of Sn2+ in catalysts but also strengthen …


Synthesis, Spectroscopic, Thermal, Crystal Structure Properties And Characterization Of New Hofmann-Type-Like Clathrates With 4-Aminopyridine And Water, Zeki̇ Kartal, Onur Şahi̇n Jan 2021

Synthesis, Spectroscopic, Thermal, Crystal Structure Properties And Characterization Of New Hofmann-Type-Like Clathrates With 4-Aminopyridine And Water, Zeki̇ Kartal, Onur Şahi̇n

Turkish Journal of Chemistry

In this study, synthesis of two new heteronuclear tetracyanonickelate(II) clathrates based on 4-aminopyridine (4AP) and guest water (H2O) molecule and investigation of their structural properties were reported. These clathrates were characterized by using vibration spectroscopy, elemental, thermal analysis and single crystal X-ray diffraction (SC-XRD) techniques. Examining the elemental and spectral data of these clathrates, it was observed that the formulas [Zn(II)(4AP)2Ni(μ-CN)2 (CN)2]·6H2O and [Cu(II)(4AP)4Ni(μ- CN)2 (CN)2]·H2O were defined their structures. General information about the structural properties of these clathrates in single crystal form has been obtained by considering the changes in the characteristic peaks of the cyanide group and the …


The Protective Role Of Melatonin Under Heavy Metal-Induced Stress In Melissa Officinalis L., Elvisa Hodzic, Semira Galijasevic, Milica Balaban, Sebila Rekanovic, Halid Makic, Biljana Kukavica, Dijana Mihajlovic Jan 2021

The Protective Role Of Melatonin Under Heavy Metal-Induced Stress In Melissa Officinalis L., Elvisa Hodzic, Semira Galijasevic, Milica Balaban, Sebila Rekanovic, Halid Makic, Biljana Kukavica, Dijana Mihajlovic

Turkish Journal of Chemistry

Heavy metals, due to their inability to degrade, pose a serious environmental and nutritional problem. The accumulation of essential and non-essential heavy metals in living organisms reduces normal growth and development, resulting in acute poisoning, disease and even death of organisms. Melatonin is a very important multifunctional molecule in protecting plants from oxidative stress due to its ability to directly neutralize reactive oxygen species (ROS). Also, melatonin has a chelating property, which may contribute in reducing metal-induced toxicity. In this paper, the protective role of melatonin in counteracting metal-induced free radical generation was highlighted. Using the HPLC-FLD technique melatonin was …


Thermal Stresses In Sofc Stacks: The Role Of Mismatch Among Thermalconductivity Of Adjacent Components, Özgür Aydin, Go Matsumoto, Yusuke Shiratori Jan 2021

Thermal Stresses In Sofc Stacks: The Role Of Mismatch Among Thermalconductivity Of Adjacent Components, Özgür Aydin, Go Matsumoto, Yusuke Shiratori

Turkish Journal of Chemistry

Generating power from renewable biogas in solid oxide fuel cells (SOFCs) is an environment-friendly, efficient, and promising energy conversion process. Biogas can be used in SOFCs via a reforming process for which dry reforming is more suitable as the reforming agent exists in the biogas mixture. Biogas can be directly reformed to H2 -rich fuel stream in the anode chamber of a SOFC by the heat released during power generation. Exploiting the heat and water produced in the SOFC for internal reforming of biogas makes the energy conversion process very efficient; however, various challenges are reported. Thus, indirect internal reforming …


Synthesis Of Hydroxy Benzoin/Benzil Analogs And Investigation Of Their Antioxidant,Antimicrobial, Enzyme Inhibition, And Cytotoxic Activities, Nuretti̇n Yayli, Gözde Kiliç, Gonca Çeli̇k, Nuran Kahri̇man, Şeyda Kanbolat, Ari̇f Bozdeveci̇, Şengül Alpay Karaoğlu, Rezzan Ali̇yazicioğlu, Hasan Erdi̇nç Selli̇tepe, İnci̇ Seli̇n Doğan, Ali̇ Aydin Jan 2021

Synthesis Of Hydroxy Benzoin/Benzil Analogs And Investigation Of Their Antioxidant,Antimicrobial, Enzyme Inhibition, And Cytotoxic Activities, Nuretti̇n Yayli, Gözde Kiliç, Gonca Çeli̇k, Nuran Kahri̇man, Şeyda Kanbolat, Ari̇f Bozdeveci̇, Şengül Alpay Karaoğlu, Rezzan Ali̇yazicioğlu, Hasan Erdi̇nç Selli̇tepe, İnci̇ Seli̇n Doğan, Ali̇ Aydin

Turkish Journal of Chemistry

In this study, hydroxy benzoin (1-7), benzil (8-14), and benzoin/benzil-O-β-D-glucosides (15-25) were synthesized to investigate their biological activities. An efficient method for synthesizing hydroxy benzoin compounds (1-7) was prepared from four different benzaldehydes using an ultrasonic bath. Then, antioxidant (FRAP, CUPRAC, and DPPH), antimicrobial (3 Gram (-), 4/6 Gram (+), one tuberculosis and one fungus), and enzyme inhibition (acetylcholinesterase, butyrylcholine esterase, tyrosinase, α-amylase, and α- glucosidase) for the all synthesized compounds (1-25) were evaluated. And also, four most active compounds (4, 12, 18a+b, and 25) from each group were evaluated to the human cervical cancer cell line (HeLa) and anticancer …


Synthesis And Antioxidant Activities Of New Nickel(Ii) Complexes Derived From 4-Benzy¬Loxysalicylidene-S-Methyl/Propyl Thiosemicarbazones, Songül Eğlence Bakir Jan 2021

Synthesis And Antioxidant Activities Of New Nickel(Ii) Complexes Derived From 4-Benzy¬Loxysalicylidene-S-Methyl/Propyl Thiosemicarbazones, Songül Eğlence Bakir

Turkish Journal of Chemistry

Six nickel(II) complexes of the N2O2 chelating thiosemicarbazones were synthesized using N1-4-benzyloxysalicylidene-S-methyl/propyl thiosemicarbazone and methoxy-substitute-salicylaldehydes in the presence of Ni(II) ion by template reaction. The structures of thiosemicarbazones and nickel(II) complexes were characterized by elemental analysis, UV-Vis, IR, and 1H-NMR spec¬troscopies. The structure of the N1-4-benzyloxysalicylidene-S-propyl thiosemicarbazone (2) was determined by X-ray single-crystal diffraction method. The total antioxidant capacities of synthesized compounds were evaluated by using cupric reducing antioxidant capacity (CUPRAC) method. The thiosemicarbazones exhibited more potent antioxidant capacity than Ni(II) complexes. Trolox equiv¬alent antioxidant capacity (TEAC) of 1c was found highest in tested nickel(II) complexes. In addition, antioxidant activities …


Synthesis, Spectroscopic, Thermal, Crystal Structure Properties, And Characterization Of New Hofmann-Td-Type Complexes With 3-Aminopyridine, Zeki̇ Kartal, Onur Şahi̇n Jan 2021

Synthesis, Spectroscopic, Thermal, Crystal Structure Properties, And Characterization Of New Hofmann-Td-Type Complexes With 3-Aminopyridine, Zeki̇ Kartal, Onur Şahi̇n

Turkish Journal of Chemistry

In this study, synthesis of two new tetracyanocadmate(II) and tetracyanozincate(II) complexes based on 3-aminopyridine (3AP) and investigation of their structural properties were reported. These complexes were characterized by using vibration spectroscopy, elemental, thermal analysis and single crystal X-ray diffraction (SC-XRD) techniques. Investigation of the elemental, spectral and single crystal data of these complexes showed that the formulas [Cd(3AP)2Zn(μ4-CN)4]n (1) and [Cd(3AP) 2Cd(μ4-CN)4]n (2) fully explained their crystal structure. General information about the structural and chemical properties of these complexes obtained in single crystal form was obtained by observing the changes in the characteristic peaks of the 3AP with the [Zn(μ4-CN)4]2- …


Phenolic Compounds, Essential Oil Composition, And Antioxidant Activity Of Angelica Pur-Purascens (Avé-Lall.) Gill, Semra Alkan Türkuçar, Ayça Aktaş Karaçeli̇k, Mustafa Karaköse Jan 2021

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, Ezgi̇ Bayrakdar Ateş, Tuba Gürkaynak Altinçeki̇ç, Mehmet Ali̇ Faruk Öksüzömer Jan 2021

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, Leri̇man Zeybel, Dursun Ali̇ Köse Jan 2021

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 …


Detection Of Bacteria Using Antimicrobial Polymer Derived Via Ring-Opening Metathesis (Romp) Pathway, N Ceren Süer, Tüli̇n Arasoğlu, Hüsnü Cankurtaran, Mustafa Okutan, Markus Gallei, Tarik Eren Jan 2021

Detection Of Bacteria Using Antimicrobial Polymer Derived Via Ring-Opening Metathesis (Romp) Pathway, N Ceren Süer, Tüli̇n Arasoğlu, Hüsnü Cankurtaran, Mustafa Okutan, Markus Gallei, Tarik Eren

Turkish Journal of Chemistry

There is growing interest in the detection of bacteria in consumables, for example, in the food and water sectors. In this study, the aim was to produce a polymer-based bacteria biosensor via ROMP (ring opening metathesis polymerization). In the first part of the study, block and random copolymers were synthesized, and their biocidal activities were tested on the glass surface. Interdigitated electrode arrays coated with the polymers possessing the highest activity were used to screen the affinity towards different bacterial strains by monitoring impedance variations in real-time. The polymer-coated electrode could detect gram-positive and gram-negative bacteria strains at a concentration …


Impact Of Graphitic Carbon Nitrides Synthesized From Different Precursors On Schottky Junction Characteristics, Orhan Altan Jan 2021

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, …


Adsorptive Performance Of Mwcnts For Simultaneous Cationic And Anionic Dyes Removal; Kinetics, Thermodynamics, And Isotherm Study, Zaheer Aslam, Irfan Yousaf, Abdul Zahir, Adnan Akhtar Jan 2021

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 …


Structural And Adsorption Behaviour Of Zno/Aminated Swcnt-Cooh For Malachite Green Removal: Face-Centred Central Composite Design, Zeynep Ci̇ğeroğlu Jan 2021

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 …


Laccase Bound To Cryogel Functionalized With Phenylalanine For The Decolorization Oftextile Dyes, Işik Perçi̇n Demi̇rçeli̇k, Yusuf Doruk Aracagök, Nesli̇han İdi̇l, Adi̇l Deni̇zli̇, Bo Mattiasson Jan 2021

Laccase Bound To Cryogel Functionalized With Phenylalanine For The Decolorization Oftextile Dyes, Işik Perçi̇n Demi̇rçeli̇k, Yusuf Doruk Aracagök, Nesli̇han İdi̇l, Adi̇l Deni̇zli̇, Bo Mattiasson

Turkish Journal of Chemistry

In this study, amino acid functionalized poly(2-hydroxyethyl methacrylate-N-methacrylolyl-l-phenylalanine) [PHEMAPA] cryogel discs were prepared. In this respect, phenylalanine containing N-methacryloyl-(L)-phenylalanine methyl ester (MAPA) was polymerized with 2-hydroxyethyl methacrylate (HEMA) without requirement of any activation step. Laccase bound poly(2-hydroxyethyl methacrylate-N-methacryloyl-l-phenylalanine) [Lac-PHEMAPA] cryogel discs were applied for decolorization of Reactive Blue-247 (RB-247). The ability of Lac-PHEMAPA cryogel discs on dye decolorization was found to be as 90% in 2 h and even more within 4h. The decolorization activities of 86% and 73% were observed at relatively low (4°C) and high (60°C) temperatures, respectively. The effect of dye concentration on dye decolorization and 100% …


Optimization For Esterification Of Saturated Palm Fatty Acid Distillate By D-Optimal Design Response Surface Methodology For Biolubricant Production, Majd Jumaah, Nadia Salih, Jumat Salimon Jan 2021

Optimization For Esterification Of Saturated Palm Fatty Acid Distillate By D-Optimal Design Response Surface Methodology For Biolubricant Production, Majd Jumaah, Nadia Salih, Jumat Salimon

Turkish Journal of Chemistry

This work presents a synthesis of palm fatty acid distillate (PFAD)-based esters to produce biolubricant oils through the esterification reaction between saturated palm fatty acid distillate (SFA-PFAD) with different types of high degree polyhydric alcohols such as trimethylolpropane (TMP), di-trimethylolpropane (Di-TMP), pentaerythritol (PE), and di-pentaerythritol (Di-PE) in the presence of sulfuric acid as catalyst. The chemical structures of synthesized SFA PFAD-based esters were characterized and confirmed by using FTIR, NMR (1H and 13C) spectroscopies and GC-FID chromatography. The FTIR spectra of SFA PFAD-based ester products clearly showed the peaks of C=O and C-O of ester group at 1732-1740 cm-1 and …


New Iodine-Apatites: Synthesis And Crystal Structure, Evgeny Bulanov, Sergey Petrov, Alexander Knyazev Jan 2021

New Iodine-Apatites: Synthesis And Crystal Structure, Evgeny Bulanov, Sergey Petrov, Alexander Knyazev

Turkish Journal of Chemistry

The paper describes methods for the preparation of compounds with an apatite structure containing only iodine atoms in the "halogen" position. The crystal structure of the compounds was refined by the Rietveld method. The resulting apatites have a structure with a space group P63/m and have the following unit cell parameters: Ba4f 1.78(2) Ba6h 2.75(2)(PO4)3I0.04(2) (a = 10.18609(34) Å, c = 7.71113(30) Å, V = 692.889(54) Å3, R = 5.448%), Pb4f 1.82(2)Pb6h 2.75(2)(PO4)3I0.13(2) (a = 9.87882(18) Å, c = 7.43222(16) Å, V = 628.144(26) Å3, R = 8.533 %), Pb4f 1.90(2)Pb6h 2.68(2)(PO4)3I0.16(2) a = 9.87058(48) Å, c = 7.41255(46) Å, …


Investigation Of Pzt-5h And Pzt-8 Type Piezoelectric Effect On Cycling Stability On Si-Mwcnt Containing Anode Materials, Mehbare Doğrusöz, Muhammed Taha Demi̇rkan, Rezan Demi̇r Çakan Jan 2021

Investigation Of Pzt-5h And Pzt-8 Type Piezoelectric Effect On Cycling Stability On Si-Mwcnt Containing Anode Materials, Mehbare Doğrusöz, Muhammed Taha Demi̇rkan, Rezan Demi̇r Çakan

Turkish Journal of Chemistry

Silicon (Si) containing materials cannot be used in commercial lithium ion batteries due to the mechanical stress problem triggered by volume expansion during cycling. The high-volume change causes mechanical instability of Si anode materials during charging/discharging, resulting fast capacity fading. It is thought that piezoelectric materials can be a solution for the volume expansion problem because of their ability to generate electric field when pressure is applied on them. For this purpose, PZT-8 and PZT-5H type piezoelectric materials were mixed with silicon and multiwalled carbon nanotube (MWCNT) to obtain anode composites and tested electrochemically versus lithium metal. The piezoelectiric effect …


Effect Of Current Density On The Microstructure And Morphology Of The Electrodepositednickel Coatings, Amel Boukhouiete, Saliha Boumendjel, Nour-El-Houda Sobhi Jan 2021

Effect Of Current Density On The Microstructure And Morphology Of The Electrodepositednickel Coatings, Amel Boukhouiete, Saliha Boumendjel, Nour-El-Houda Sobhi

Turkish Journal of Chemistry

The aim of this research work was to study the effect of deposition current density on microstructure and surface morphology of electrodeposited nickel coatings. For this purpose, nickel deposits have been synthesized by direct current from Watts bath without additive, to limit the incorporation of pollutants resulting from surface adsorption or electro-activity of these compounds. Nickel deposits have been investigated by scanning electron microscopy and X-ray diffraction. Cyclic voltammetry was also used to gain information on the general behavior of the deposition. The optimum conditions of deposition were established and the influence of current density on the grain size, surface …


Glucosamine Derived Hydrothermal Carbon Electrodes For Aqueous Electrolyte Energy Storage Systems, Burcu Ünal, Rezan Demi̇r Çakan Jan 2021

Glucosamine Derived Hydrothermal Carbon Electrodes For Aqueous Electrolyte Energy Storage Systems, Burcu Ünal, Rezan Demi̇r Çakan

Turkish Journal of Chemistry

Nitrogen-doped porous hard carbons are synthesized by hydrothermal carbonization method (HTC) using glucosamine as biosource and treated at different carbonization temperatures in nitrogen environment (500, 750, 1000 °C). The electrochemical performances of hard carbons electrode materials for aqueous electrolyte sodium ion batteries are examined to observe the effect of two different voltage ranges (-0.8-0.0) V and (0.0-0.8) V in 1.0 M Na2SO4 aqueous electrolyte. The best electrochemical performances are acquired for the 1000 °C treated glucosamine (GA-1000) porous carbon sample that provides ~96 F/g capacitance value in the negative voltage range (between -0.8 and 0.0) V. The sodium diffusion coefficient …


Antiinflammatory Photodynamic Therapy Potential Of Polyoxyethylene-Substituted Perylene Diimide, Nitrocatechol, And Azo Dye, Özgül Hakli, Kasim Ocakoğlu, Furkan Ayaz Jan 2021

Antiinflammatory Photodynamic Therapy Potential Of Polyoxyethylene-Substituted Perylene Diimide, Nitrocatechol, And Azo Dye, Özgül Hakli, Kasim Ocakoğlu, Furkan Ayaz

Turkish Journal of Chemistry

Photodynamic therapy (PDT) applications enable light-controlled activation of drug candidates instead of their constitutive activities to prevent undesired side effects associated with their constant activities. A specific wavelength of light is utilized to enable electron mobility in the chemical structure, which results in differential activities that may alter cell viability and cellular functions. Canonical photodynamic therapy applications mostly focus on cytotoxicity-based antimicrobial and anticancer properties of the PDT agents. In this study, we focused on subtoxic concentrations of three different molecules containing polyoxyethylene group and examined their antiinflammatory activities on stimulated mammalian macrophages. Stimulated macrophages produce proinflammatory cytokines TNF and …


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 Jan 2021

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 …


A Facile Approach For The Synthesis Of Porous Hematite And Magnetite Nanoparticles Through Sol-Gel Self-Combustion, Imene Gritli, Afrah Bardaoui, Jamila Ben Naceur, Salah Ammar, Mohammad Abu Haija, Sherif Mohamed Abdel Salam Keshk, Radhouane Chtourou Jan 2021

A Facile Approach For The Synthesis Of Porous Hematite And Magnetite Nanoparticles Through Sol-Gel Self-Combustion, Imene Gritli, Afrah Bardaoui, Jamila Ben Naceur, Salah Ammar, Mohammad Abu Haija, Sherif Mohamed Abdel Salam Keshk, Radhouane Chtourou

Turkish Journal of Chemistry

Porous magnetite (Fe3O4) and hematite (α-Fe2O3) nanoparticles were prepared via the sol-gel auto-combustion method. The gels were prepared by reacting ferric nitrates (as oxidants) with starch (as fuel) at an elevated temperature of 200 °C. Different ratios (Φ) of ferric nitrates to starch were used for the synthesis (Φ = fuel/oxidant). The synthesized iron oxides were characterized by Fourier transform infrared (FT-IR) spectroscopy, Raman spectroscopy, X-ray diffraction (XRD) spectroscopy, scanning electron microscopy (SEM), transmission electron microscopy (TEM), Brunauer-Emmet-Teller (BET) and vibrating sample magnetometer (VSM) analysis techniques. The crystal structure, morphology, and specific surface area of the iron oxide nanoparticles (Fe3O4 …


Volatile Constituents Of Three Thymus Sipyleus Boiss. Subspecies From Different Sites In Turkey, Hale Gamze Ağalar, Mi̇ne Kürkçüoğlu, Kemal Hüsnü Can Başer, Kenan Turgut Jan 2021

Volatile Constituents Of Three Thymus Sipyleus Boiss. Subspecies From Different Sites In Turkey, Hale Gamze Ağalar, Mi̇ne Kürkçüoğlu, Kemal Hüsnü Can Başer, Kenan Turgut

Turkish Journal of Chemistry

This study was designed to reveal the chemical diversity of some Thymus sipyleus subspecies growing wild in Turkey and to compare the volatile compound profiles by using micro(hydro)distillation technique. For this purpose, volatile compounds isolated by microdistillation from nine samples (three plant samples collected from different regions in Antalya) of Thymus sipyleus Boiss. subsp. sipyleus var. sipyleus, T. sipyleus Boiss. subsp. sipyleus var. davisianus Ronniger, and T. sipyleus Boiss. subsp. rosulans (Borbas) Jalas were analyzed by GC and GC-MS systems. 1,8-Cineole, p-cymene, α-terpineol and carvacrol were identified as major compounds in T. sipyleus subsp. sipyleus var. sipyleus samples. Geranial, neral, …


A Four-Component Modified Biginelli Reaction: A Novel Approach For C-2 Functionalizeddihydropyrimidines, Harsha Narkhede, Avinash Dhake, Vaidhyanathan Balasubramaniyan Jan 2021

A Four-Component Modified Biginelli Reaction: A Novel Approach For C-2 Functionalizeddihydropyrimidines, Harsha Narkhede, Avinash Dhake, Vaidhyanathan Balasubramaniyan

Turkish Journal of Chemistry

A novel four component modified Biginelli reaction for the synthesis of C-2 functionalized dihydropyrimidines has been established. The approach uses assembly of less explored acetyl acetone with aromatic aldehyde, thiourea, and dimethyl sulphate to construct a novel 5-acetyl 2-methylthio dihydropyrimidine system, which works as an efficient well-designed intermediate for generating C-2 modified Biginelli libraries with nitrogen nucleophiles. Phenyl hydrazine, semicarbazide, and aryl semicarbazides are successfully used as N-nucleophiles to generate C-2 functionalized dihydropyrimidine derivatives, which fulfil the demands of active pharmacophore. Time economy, step economy, and a single pot reaction with moderate to excellent yield are the major advantages of …


Evaluation Of Quercetin As A Potential Β-Lactamase Ctx-M-15 Inhibitor Via The Molecular Docking, Dynamics Simulations, And Mmgbsa, Emrah Sariyer, Ayşegül Saral Jan 2021

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 …


New Chlorogenic Acid Derivatives And Triterpenoids From Scorzonera Aucheriana, İshak Eri̇k, Kami̇l Çoşkunçelebi̇, Serdar Makbul, Nuretti̇n Yayli Jan 2021

New Chlorogenic Acid Derivatives And Triterpenoids From Scorzonera Aucheriana, İshak Eri̇k, Kami̇l Çoşkunçelebi̇, Serdar Makbul, Nuretti̇n Yayli

Turkish Journal of Chemistry

Chromatographic separation of n-hexane and ethyl acetate fraction of a crude methanol extract obtained from aerial parts of the Scorzonera aucheriana DC collected from Sivas province of Turkey yielded nine natural compounds; two new 3-caffeoyl-quinic acid analogs (1-2), one new taraxasterol oleate (3), and six known triterpenoids taraxasterol (4), taraxasterol acetate (5), ptiloepoxide (6), lupeol (7), lupeol acetate (8), and β-sitosterol (9) were characterized. The structures of the isolated compounds were elucidated on the basis of NMR (1H, 13C, COSY, HMBC, HSQC, and TOCSY), UV, FT-IR and LC-Q-TOF-MS spectrometric data.


Microwave Assisted, Sequential Two-Step, One-Pot Synthesis Of Novel Imidazo[1,2-A]Pyrimidine Containing Tri/Tetrasubstituted Imidazole Derivatives, Tuğba Güngör Jan 2021

Microwave Assisted, Sequential Two-Step, One-Pot Synthesis Of Novel Imidazo[1,2-A]Pyrimidine Containing Tri/Tetrasubstituted Imidazole Derivatives, Tuğba Güngör

Turkish Journal of Chemistry

A series of novel imidazo[1,2-a]pyrimidine containing tri/tetrasubstituted imidazole derivatives (1-10) has been synthesized via sequential two-step, one-pot, multicomponent reaction using imidazo[1,2-a]pyrimidine-2-carbaldehyde, benzil, primary amines, and ammonium acetate catalyzed by p-toluenesulfonic acid under microwave-assisted conditions. The results showed that target compounds can be obtained from a wide range of primary amines bearing different functional groups with moderate to good yields (46%-80%) under optimum reaction conditions. This method provides a green protocol for imidazo[1,2-a]pyrimidine containing tri/ tetrasubstituted imidazole derivatives due to ethyl alcohol as a green solvent, microwave irradiation as a greener heating method and one-pot multicomponent reaction as a green technique. …


Vortex-Assisted Magnetic Solid Phase Extraction Of Pb And Cu In Some Herb Samples On Magnetic Multiwalled Carbon Nanotubes, Di̇lek Kamaş, Aslihan Karatepe, Mustafa Soylak Jan 2021

Vortex-Assisted Magnetic Solid Phase Extraction Of Pb And Cu In Some Herb Samples On Magnetic Multiwalled Carbon Nanotubes, Di̇lek Kamaş, Aslihan Karatepe, Mustafa Soylak

Turkish Journal of Chemistry

This study is the development of a new solid phase extraction method based on using magnetic multiwalled carbon nanotubes impregnated with 1-(2-pyridylazo)2-naphthol (PAN) for separation, preconcentration, and flame atomic absorption spectrometric determination of Pb(II) and Cu(II). Optimization of the method was done by investigating pH effect, amount of magnetic multiwalled carbon nanotubes impregnated with PAN, eluent type and volume, matrix effects, and volume of the sample. The optimum adsorbent amount was found to be 75 mg and the optimum pH value was found as 5.5. The detection limits were 16.6 μg L-1 for Pb(II) and 18.9 μg L-1 for Cu(II). …


Co2 Hydrogenation To Methanol And Dimethyl Ether At Atmospheric Pressure Using Cu-Ho-Ga/Γ-Al2o3 And Cu-Ho-Ga/Zsm-5: Experimental Study And Thermodynamic Analysis, Cansu Tuygun, Bahar İpek Jan 2021

Co2 Hydrogenation To Methanol And Dimethyl Ether At Atmospheric Pressure Using Cu-Ho-Ga/Γ-Al2o3 And Cu-Ho-Ga/Zsm-5: Experimental Study And Thermodynamic Analysis, Cansu Tuygun, Bahar İpek

Turkish Journal of Chemistry

CO2 valorization through chemical reactions attracts significant attention due to the mitigation of greenhouse gas effects. This article covers the catalytic hydrogenation of CO2 to methanol and dimethyl ether using Cu-Ho-Ga containing ZSM-5 and γ-Al2O3 at atmospheric pressure and at temperatures of 210 °C and 260 °C using a CO2:H2 feed ratio of 1:3 and 1:9. In addition, the thermodynamic limitations of methanol and DME formation from CO2 was investigated at a temperature range of 100?400 °C. Cu-Ho-Ga/γ-Al2O3 catalyst shows the highest formation rate of methanol (90.3 μmolCH3OH/gcat/h ) and DME (13.2 μmolDME/gcat/h) as well as the highest selectivity towards …