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Full-Text Articles in Chemistry

Detailed Structure Analyses On Cobalt Doped Pbtio3 Powders, Ebru Erünal Jan 2022

Detailed Structure Analyses On Cobalt Doped Pbtio3 Powders, Ebru Erünal

Turkish Journal of Chemistry

The identification of the defects and secondary phases which significantly affect the material properties are of crucial importance. In this study, a systematic structure examination of PbTiO3 and cobalt doped PbTiO3 powder ceramics was carried out. X-ray diffraction (XRD), Fourier-transform infrared (FT-IR), Raman, and electron paramagnetic resonance (EPR) spectroscopies were applied along with nonsimultaneous thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC). The doped and undoped PbTiO3 materials were synthesized via a practical sol-gel route that takes place at 50 °C. The perovskite formation for both materials was verified. The dislocation density of cobalt doped PbTiO3 was found to be …


A Theoretical Study Of Co Adsorption On Cu(211) Surface With Coverage Effects, Murat Oluş Özbek Jan 2022

A Theoretical Study Of Co Adsorption On Cu(211) Surface With Coverage Effects, Murat Oluş Özbek

Turkish Journal of Chemistry

CO adsorption on the Cu(211) surface was investigated using energy, geometry and vibrational data, which were produced through periodic DFT computations. Adsorption on the (111) terrace, as well as the previously reported top and bridge sites of the step-edges, was studied at 0.25, 0.33, 0.50, 0.66, 0.75, and 1.00 monolayer (ML) CO coverage. Results showed that up to and including 0.50 ML, on-top or bridge adsorption is preferred on the step-edges. When 0.50 ML is exceeded, top-bridge alternating patterns become feasible on the step edges along with possible shifts towards the terrace. Several feasible patterns were identified at 0.66, 0.75, …


Simulation Of Two Electrode Reactions Coupled By The Chemical Reaction, Milivoj Lovric Jan 2022

Simulation Of Two Electrode Reactions Coupled By The Chemical Reaction, Milivoj Lovric

Turkish Journal of Chemistry

A model of an ECE mechanism consisting of two reversible electrode reactions coupled by the kinetically controlled, second order, reversible chemical reaction is developed for the staircase cyclic voltammetry on the rotating disk electrode. The relationship between the limiting current of the second wave and the rate constant of chemical reaction is investigated. The concentration of electroinactive component of the forward reaction influences the half-wave potential of the first wave and the limiting current of the second wave. The responses of the mechanisms with reversible and irreversible chemical reactions are compared.


Antimicrobial And Lipase Inhibition Of Essential Oil And Solvent Extracts Of Cota Tinctoria Var. Tinctoria And Characterization Of The Essential Oil, İshak Eri̇k, Gözde Bozdal, Sila Özlem Şener, Büşra Korkmaz, Şengül Alpay Karaoğlu, Sali̇h Terzi̇oğlu, Nuretti̇n Yayli Jan 2022

Antimicrobial And Lipase Inhibition Of Essential Oil And Solvent Extracts Of Cota Tinctoria Var. Tinctoria And Characterization Of The Essential Oil, İshak Eri̇k, Gözde Bozdal, Sila Özlem Şener, Büşra Korkmaz, Şengül Alpay Karaoğlu, Sali̇h Terzi̇oğlu, Nuretti̇n Yayli

Turkish Journal of Chemistry

The essential oil (EO) of Cota tinctoria var. tinctoria was analyzed using GC-FID / MS. A total of 51 compounds were determined from this taxon, accounting for 99.79% in hydrodistillation. Monoterpenes were the primary chemical class for the volatile organic compounds in the EO (36.1%, 13 compounds). Borneol (18.1%), camphor (14.9%), and β-pinene (11.3%) were the major components in the EO of C. tinctoria var. tinctoria. The antimicrobial activities of EO and n-hexane, acetonitrile, methanol, and water solvent extracts of the taxon were screened in vitro against ten microorganisms. The EO yielded the best activity (15 mm, 372.5 MIC, 59600 …


Green Synthesis, Characterisation Of Au And Ag Nanoparticles By Various Bioextracts And Their Usability At Graphite Electrode Modification, Emi̇ne Arslan, Ender Bi̇çer, Eli̇f Sekmen, Semi̇ha Çakir Jan 2022

Green Synthesis, Characterisation Of Au And Ag Nanoparticles By Various Bioextracts And Their Usability At Graphite Electrode Modification, Emi̇ne Arslan, Ender Bi̇çer, Eli̇f Sekmen, Semi̇ha Çakir

Turkish Journal of Chemistry

In this study, the biosynthesis of Au and Ag nanoparticles (AuNp and AgNp) with a green chemistry approach was performed by using bioextracts of various fruits and vegetables (Lycopersicon esculentum (LE), Cucumis sativus (CS), Malus domestica (MD), Cucurbita pepo (CP), Apiumgraveolens var. rapaceum (AVR), Prunus cerasifera (PC), Oleraceae var. botrytis (OVB)). In the determination of optimum experimental conditions, the parameters such as the type and concentration of bioextract, concentration of metal ion solutions, the ratio of metal ion solution to bioextract, pH, reaction time and temperature were found to be significant. The characterisation of AuNp and AgNp synthesized by providing …


Intrinsically Fluorescent And Quercetin Loaded Highly Crosslinked Polyphosphazene Nanospheres: Synthesis, Characterization And Fluorescence Properties, Si̇mge Meti̇noğlu Örüm Jan 2022

Intrinsically Fluorescent And Quercetin Loaded Highly Crosslinked Polyphosphazene Nanospheres: Synthesis, Characterization And Fluorescence Properties, Si̇mge Meti̇noğlu Örüm

Turkish Journal of Chemistry

Highly crosslinked, inorganic-organic hybrid and intrinsically fluorescent polyphosphazene nanospheres bearing hydroxyl groups on the surface are facilely generated via a one-pot polycondensation of octachlorocyclotetraphosphazene, fluorescein and quercetin. The resulting nanospheres were characterised by scanning electron microscopy (SEM), energy-dispersive X-ray analysis (EDX), Fourier transform infrared spectroscopy (FTIR), dynamic light scattering (DLS), X-ray diffraction analysis (XRD) and ultraviolet-visible spectroscopy (UV-vis) techniques. The average diameter of the nanospheres was determined as 379 nm. Also, quercetin which is both a monomer and an anticancer drug was loaded to the nanospheres as 446 mg g-1. The obtained nanospheres possess outstanding disperse ability in both aqueous …


Preparation Of Moo3/Mos2-E Composite For Enhanced Photoelectrocatalytic Removal Of Antimony From Petrochemical Wastewaters, Sevi̇l Akçağlar Jan 2022

Preparation Of Moo3/Mos2-E Composite For Enhanced Photoelectrocatalytic Removal Of Antimony From Petrochemical Wastewaters, Sevi̇l Akçağlar

Turkish Journal of Chemistry

By doping of MoO3 to MoS2-E, MoO3/MoS2-E composite was produced to treat the antimony (Sb+5) from raw petrochemical industry wastewater. The effects of increasing MoO3/MoS2-E composite concentrations (0.01, 0.06, 0.50, 1.20, and 6 mg/L), times (5 min, 10 min, 20 min, 60 min, 80 min), and simulated sun light powers (2, 15, and 26 mW/m2) on the removal of Sb+5 was researched. According to X-ray diffraction (XRD), MoS2-E exhibited a pure hexagonal structure with peaks at 2θ data of 15.56, 33.78, 40.59, and 61.43 cm …


Ultrasound Phantom With Solids Mimicking Cancerous Tissue For Needle Breast Biopsy, Işik İpek Avci Yayla, Meli̇s Bi̇lal, Artür Salmaslioğlu, Erol Erçağ, Esma Sezer, Belkis Ustamehmetoglu Jan 2022

Ultrasound Phantom With Solids Mimicking Cancerous Tissue For Needle Breast Biopsy, Işik İpek Avci Yayla, Meli̇s Bi̇lal, Artür Salmaslioğlu, Erol Erçağ, Esma Sezer, Belkis Ustamehmetoglu

Turkish Journal of Chemistry

This study aimed at synthesizing hydrogels to simulate opaque breast tissue (BT) and coloured cancerous tissues (CT) at different densities of the designed phantom to improve the biopsy-related skills along with ultrasonography. Both tissues are tear-resistant and therefore, the phantom can be trained multiple times in order to lower the price and improve the eye-hand coordination of users. For this purpose, self-healing (SH) polyacrylamide (PAAm) hydrogels (SH hydrogel) obtained by free-radical polymerization of AAm, in the presence of chemical cross-linker, BAAm, physical cross-linker stearyl methacrylate, C18, and ammonium persulfate APS as initiator were used in the design of phantoms. Psyllium …


A New Electrochromic Copolymer Composed Of 4,7-Di(Thiophen-2-Yl)Benzo[C] [1,2,5] Thiadiazole And 3,4-Ethylenedioxythiophene, Kübra Çeli̇k, Ari̇f Kivrak, Buket Çarbaş Jan 2022

A New Electrochromic Copolymer Composed Of 4,7-Di(Thiophen-2-Yl)Benzo[C] [1,2,5] Thiadiazole And 3,4-Ethylenedioxythiophene, Kübra Çeli̇k, Ari̇f Kivrak, Buket Çarbaş

Turkish Journal of Chemistry

A new electrochromic copolymer based on 4,7-di(thiophen-2-yl)benzo[c] [1,2,5]thiadiazole and 3,4-ethylenedioxythiophene was successfully obtained via the electrochemical polymerization method in the medium of electrolyte solution, which consists of 0.1 M tetrabutylammonium hexafluorophosphate and dichloromethane. In order to compare the electrochemical and chemical properties of the copolymer, the benzothiodiazole derivative and 3,4-ethylenedioxythiophene (EDOT) monomers, which are parts of the copolymer, are electrochemically polymerized, separately in the same environment and concentration with the copolymer. Poly(4,7-di(thiophen- 2-yl)benzo[c][1,2,5]thiadiazole) (P(TBT)) and poly(3,4-ethylenedioxythiophene) (PEDOT) polymers were obtained. Before starting the electrochemical synthesis, the initial oxidation potentials of the monomers that form the copolymer were compared via the …


Comparison Of Denaturing Agent Effects In Enzymatic N-Glycan Release For Human Plasma N-Glycan Analysis, Haci Mehmet Kayili, Rokia Sakhta, Beki̇r Sali̇h Jan 2022

Comparison Of Denaturing Agent Effects In Enzymatic N-Glycan Release For Human Plasma N-Glycan Analysis, Haci Mehmet Kayili, Rokia Sakhta, Beki̇r Sali̇h

Turkish Journal of Chemistry

Glycosylation is an essential posttranslational modification observed in the living proteome. Glycosylation profiles in glycoproteins can change in commonly observed diseases such as cancer. Identifying these changes is crucial in discovering new biomarkers for the early diagnosis of cancer. One of the main steps of N-glycan analysis is to release N-glycans from glycoproteins by specific enzymes. The study compares common denaturing agent combinations used in N-glycan release methods. In the study, human plasma was used to test the release methods of N-glycans containing different detergent combinations. The released N-glycans were labeled with the procainamide tag, …


High-Efficiency Removal Of Cationic Dye And Heavy Metal Ions From Aqueous Solution Using Amino-Functionalized Graphene Oxide, Adsorption Isotherms, Kinetics Studies, And Mechanism, Meti̇n Çelebi̇, Eda Gökirmak Söğüt Jan 2022

High-Efficiency Removal Of Cationic Dye And Heavy Metal Ions From Aqueous Solution Using Amino-Functionalized Graphene Oxide, Adsorption Isotherms, Kinetics Studies, And Mechanism, Meti̇n Çelebi̇, Eda Gökirmak Söğüt

Turkish Journal of Chemistry

GO-NH2 (amino functionalized graphene oxide) was synthesized by grafting (3-aminopropyl) triethoxysilane onto the surface GO (graphene oxide). The GO-NH2 with a higher surface area and many active sites was characterized and its effectiveness in removing Rhod B dye and Ni(II) ions from wastewater by adsorption was observed. The effects of pH, time, and strange ions on the adsorption efficiency were investigated. The equilibrium isotherm data confirmed that it fits the Langmuir and Freundlich isotherm models. GO and GO-NH2 exhibited high adsorption capacity (QM); 2500 (mg L-1) and 3333 (mg L-1) for …


Single And Selective Transport Of Zr(Iv) Ions With Trioctyl Amine Dissolved In Kerosene Using A Multidropped Liquid Membrane Technique, Fatma Tezcan, Ramazan Donat Jan 2022

Single And Selective Transport Of Zr(Iv) Ions With Trioctyl Amine Dissolved In Kerosene Using A Multidropped Liquid Membrane Technique, Fatma Tezcan, Ramazan Donat

Turkish Journal of Chemistry

It is very important to develop a process for selectively extracting Zr(IV) ions from the solution medium to produce zirconium metal used in industry and nuclear reactors. In this study, the parameters affecting the extraction of Zr(IV) ions were investigated using a multidropped liquid membrane (MDLM) system. Trioctyl amine (TOA) dissolved in kerosene was used as a carrier ligand in the extraction of Zr(IV) ions by the MDLM technique. The effect of carrier concentration and stripping solution concentration, pH, and the temperature in the donor phase on the transport of Zr(IV) were investigated. The optimum condition for the transportation of …


Parameter Effect Quantification For A Phase Change Material-Based Lithium-Ion Battery Thermal Management System, Uğur Morali Jan 2022

Parameter Effect Quantification For A Phase Change Material-Based Lithium-Ion Battery Thermal Management System, Uğur Morali

Turkish Journal of Chemistry

The influence of discharge rate, ambient temperature, and phase change material on the maximum temperature and the highest temperature difference was investigated. The maximum temperature of the battery was tested with and without phase change material under extreme discharge rates (4C and 5C) and ambient temperatures (310 K and 320 K). Results showed that a phase change material reduced the maximum temperature from 327.94 K to 306.45 K for a 14.6 Ah lithium-ion battery discharged at 5C-rate and 320 K. Quantitatively determined parameter effects revealed that the PCM parameter considerably had a remarkable influence on maximum temperature compared to discharge …


Moo3, Tio2, And Motio5 Based Oxide Semiconductor For Photovoltaic Applications, Fatma Bayrakçeken Jan 2022

Moo3, Tio2, And Motio5 Based Oxide Semiconductor For Photovoltaic Applications, Fatma Bayrakçeken

Turkish Journal of Chemistry

Topographic essential synthesis of nanomaterials by adjusting easy preparatory factors is an effective way to improve a variety of nanostructured materials. The SILAR technique is used to evaluate the manufacturing samples of MoO3, TiO2, and MoTiO5 nanostructures. These nanostructures of MoO3, TiO2, and MoTiO5 are used as electrode materials in photovoltaic systems. The link between photoelectrochemical characteristics and MoO3, TiO2, and MoTiO5 nanostructures is studied in depth. The photoelectrochemical characteristics of MoO3, TiO2, and MoTiO5 nanostructures are discovered to be …


Release Of Nifedipine, Furosemide, And Niclosamide Drugs From The Biocompatible Poly(Hema) Hydrogel Structures, Bahar Yilmaz Jan 2022

Release Of Nifedipine, Furosemide, And Niclosamide Drugs From The Biocompatible Poly(Hema) Hydrogel Structures, Bahar Yilmaz

Turkish Journal of Chemistry

The primary aim of this article was to improve the solubility and bioavailability of the drugs nifedipine, niclosamide, and furosemide due to their poor solubility and dissolution rate. Therefore, these drugs require improvement in solubility and dissolution rate in formulation development, especially in solid dosage forms such as hydrogels and capsules. Hydrogel structures were synthesized by using a biocompatible, nontoxic, and protective pure 2-hydroxy ethyl methacrylate (HEMA) monomer. These hydrogel structures were characterized by various techniques such as scanning electron microscopy and Fourier-transformed infrared spectroscopy. In the next step, drug molecules were loaded in the poly (HEMA) hydrogels. Drug releases …


Amin-Modified Graphene Oxide As A Promising Adsorbent For Selective Extraction Of Dexamethasone Adulterant From Herbal Supplements, Mahboob Nemati, Ali Zayer, Samin Hamidi Jan 2022

Amin-Modified Graphene Oxide As A Promising Adsorbent For Selective Extraction Of Dexamethasone Adulterant From Herbal Supplements, Mahboob Nemati, Ali Zayer, Samin Hamidi

Turkish Journal of Chemistry

In most cases, herbal supplements found in illegal centers and herbal medicine stores have harmful content that causes irreparable damage to people. As a representative of the green chemistry method, a rapid and efficient dispersive micro solid-phase extraction (D-mSPE) method was applied to extract dexamethasone adulterant from handmade supplements sold as power natural enhancing materials. The quantification of the analyte was performed by high performance liquid chromatography with an ultraviolet detector. Effective parameters on the extraction recovery, including the type and amount of adsorbent, the kind of elution solvent, and the time of extraction and elution, were systematically investigated. The …


Thermal Versus Photochemical Tautomerization Of Cytosine And Guanine: A Blyp Computational Study Along The Irc Curves, Tsvetina Cherneva, Vassil Delchev Jan 2022

Thermal Versus Photochemical Tautomerization Of Cytosine And Guanine: A Blyp Computational Study Along The Irc Curves, Tsvetina Cherneva, Vassil Delchev

Turkish Journal of Chemistry

We performed a theoretical study, at the BLYP/aug-cc-pVDZ theoretical level, of the mechanisms of H-transfer between biologically relevant tautomers of cytosine and guanine. The analysis of the ground- and excited state energy barriers of the conversions showed that in some cases they are lower as compared to the ground state reactions. The inclusion of one water molecule as a catalyst in the oxo-amino form of cytosine and guanine drastically changes the mechanism of the reactions in the ground as well as in the excited state. For example, the ground state reaction path of cytosine reduces the energy barrier from 165 …


Study On Moo3/Sba-16 Catalyzed Transesterification To Synthesize Diphenyl Carbonate, Ying Li, Shunwu He Jan 2022

Study On Moo3/Sba-16 Catalyzed Transesterification To Synthesize Diphenyl Carbonate, Ying Li, Shunwu He

Turkish Journal of Chemistry

In this paper, the mesoporous molecular sieve SBA-16 with good dispersion was prepared by hydrothermal method. Under the condition of Si/Mo= 1.0, MoO3/SBA-16 catalysts were prepared by iso-dipping method at 550 °C, 650 °C and 750 °C calcination temperature, which for the synthesis of diphenyl carbonate (DPC) from dimethyl carbonate (DMC) and phenyl acetate (PA) was used, and the uncalcined MoO3/SBA-16 was used as a reference. XRD, TG-DTA, XPS, ICP-MS, FT-IR, BET, SEM and TEM characterization. The effects of calcination temperature and reaction conditions on the catalytic performance of MoO3/SBA-16 in transesterification of DMC and PA …


Miscibility And Thermal Behavior Of Poly(Methyl Methacrylate) And Polystyrene Blend Using Benzene As A Common Solvent, Arshiya Iqbal, Jamil Muhammad, Farzana Ahmad, Mohsan Nawaz, Musa Kaleem Baloch, Luqman Mohammad Jan 2022

Miscibility And Thermal Behavior Of Poly(Methyl Methacrylate) And Polystyrene Blend Using Benzene As A Common Solvent, Arshiya Iqbal, Jamil Muhammad, Farzana Ahmad, Mohsan Nawaz, Musa Kaleem Baloch, Luqman Mohammad

Turkish Journal of Chemistry

Polymer blending is one of the advanced technologies to attain polymeric material with tailored properties. In this work, the miscibility of Poly(methyl methacrylate) (PMMA) and Polystyrene (PS) blend in benzene was investigated by employing various techniques such as FTIR spectroscopy, viscosity measurement technique, light scattering techniques, DSC and TGA techniques over an extended range of concentrations, compositions, and temperatures. The results revealed that there exist hydrogen bonding and hydrodynamic interactions which led these polymers to get miscible to a large extent. The compatibility increased with the increasing PS contents or increase in temperature of the system. In addition, the thermal …


Encapsulation Of Halocadmate Anion Via Hydrogen Bonding: Synthesis And Characterization Of Bis(Diethylenetriamine)Cobalt(Iii) Complex Containing Hexabromocadmate Anion, Vinit Prakash, Ritu Bala, Amrinder Kaur, Daron E. Janzen Jan 2022

Encapsulation Of Halocadmate Anion Via Hydrogen Bonding: Synthesis And Characterization Of Bis(Diethylenetriamine)Cobalt(Iii) Complex Containing Hexabromocadmate Anion, Vinit Prakash, Ritu Bala, Amrinder Kaur, Daron E. Janzen

Turkish Journal of Chemistry

In this work, the encapsulation of [CdBr6]4- by six cations, [Co(dien)2]3+ has been described with the help of single crystal X-ray structural study in the complex, mer-[Co(dien)2]2[CdBr6]Br2. The complex anion, [CdBr6]4- has been obtained through solution method while attempting to synthesize complex dianion, [CdBr4]2-. This newly synthesized complex has been initially characterized by elemental analyses and spectroscopic studies (IR, NMR and UV-Visible). IR and NMR studies have been used for the isomeric identification of [Co(dien)2]3+ …


Investigation Of Glycerol Electrooxidation Activity Of Carbon Supported Pdcu Bimetallic Electrocatalyst, Kübranur Ağtoprak, Merve Doğan Özcan, Ayşe Ni̇lgün Akin, Rami̇z Gülteki̇n Akay Jan 2022

Investigation Of Glycerol Electrooxidation Activity Of Carbon Supported Pdcu Bimetallic Electrocatalyst, Kübranur Ağtoprak, Merve Doğan Özcan, Ayşe Ni̇lgün Akin, Rami̇z Gülteki̇n Akay

Turkish Journal of Chemistry

In this study, Pd/C, Cu/C, and a series of PdCu/C bimetallic electrocatalysts were prepared by microwave-assisted modified polyol method to determine glycerol electrooxidation reaction (GOR) activities. The effect of microwave duration on catalyst structure and GOR activity was investigated on PdCu/C bimetallic catalysts. Also, a commercial Pd/C (com-Pd/C) was used to compare catalytic activities with prepared samples. Electrocatalysts were characterized by using X-ray Diffraction (XRD), Inductively Coupled Plasma Optical Emission Spectroscopy (ICP-OES), and Transmission Electron Microscopy (TEM) analyses. In addition, the activity and stability of electrocatalysts for GOR were examined by using cyclic voltammetry (CV) and chronoamperometry (CA). In XRD …


Determination Of Si/Graphite Anode Composition For New Generation Li-Ion Batteries: A Case Study, İlknur Kalafat, Nesli̇han Yuca Jan 2022

Determination Of Si/Graphite Anode Composition For New Generation Li-Ion Batteries: A Case Study, İlknur Kalafat, Nesli̇han Yuca

Turkish Journal of Chemistry

Silicon with the properties of high capacity capability, moderate working potential, environmental sensitivity, and existence are the highly promising anode materials for lithium-ion batteries. Silicon anodes have disadvantageous properties and advantages like 300% volume change during lithium insertion and extraction process that can result in capacity fading and a shorter lifetime of the battery. In the literature, different optimizations of Silicon with different nanomaterials or composite materials, in different ratios, and with different binders and different procedures have been studied. The physical mixing of silicon with carbon provides a good performance by combining the high lithium storage capacity of the …