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Full-Text Articles in Physical Sciences and Mathematics

Determination Of Essential Oil And Biological Activities Of Hypericum Ternatum Poulter And H. Scabrum L. Species Collected From Different Localities: Is H. Scabrum An Alternative To Multifunctional Species St John's Wort (H. Perforatum)?, Mehmet Akdeni̇z, İsmai̇l Yener, Sevgi̇ İrtegün Kandemi̇r, Şafak Özhan Kocakaya, Mehmet Firat, Serkan Yi̇ği̇tkan, Nesri̇n Haşi̇mi̇ Besen, Abdulselam Ertaş, Ufuk Kolak Jan 2022

Determination Of Essential Oil And Biological Activities Of Hypericum Ternatum Poulter And H. Scabrum L. Species Collected From Different Localities: Is H. Scabrum An Alternative To Multifunctional Species St John's Wort (H. Perforatum)?, Mehmet Akdeni̇z, İsmai̇l Yener, Sevgi̇ İrtegün Kandemi̇r, Şafak Özhan Kocakaya, Mehmet Firat, Serkan Yi̇ği̇tkan, Nesri̇n Haşi̇mi̇ Besen, Abdulselam Ertaş, Ufuk Kolak

Turkish Journal of Chemistry

The importance of Hypericum L. species, being used in traditional medicine, in the scientific world is increasing day by day. Hypericum species are plants that have been used in the treatment of many diseases for a long time and have healing properties. In the current study, the essential oil compositions of Hypericum scabrum L. and H. ternatum Poulter collected from different localities in Turkey were determined by GC-MS/FID. In addition, their antioxidant, cytotoxic, and antimicrobial activities with their enzyme inhibitory potentials (cholinesterase, urease, tyrosinase, elastase, and collagenase) were investigated. Also, in vitro and in silico studies of the major components …


Synthesis, Characterization, And Antimicrobial Evaluation Of Polyvinylalcohol-Osthol Composite Films, Ishrat Gowsia, Feroz Mir, Javid Banday Jan 2022

Synthesis, Characterization, And Antimicrobial Evaluation Of Polyvinylalcohol-Osthol Composite Films, Ishrat Gowsia, Feroz Mir, Javid Banday

Turkish Journal of Chemistry

Although poly-vinyl alcohol (PVA) has certain mechanical drawbacks such as a weak barrier, it has widely been used in food packaging over the last many years. To increase the suitability of PVA (C2H4O)n and render it ideal for food packaging, a diversity of studies have already been carried out. In the below-mentioned script, we, for the first time, report the use of natural product osthol in making a new composite with PVA for enhancing thermal, physicochemical, and antimicrobial properties. The significant aim of the report is the insertion of osthol (C15H16O3 …


Chromatographic Profile Of Major Whey Proteins In Some Dairy Beverages Based On Milk Serum, Doina Prodan, Miuta Filip, Mihaela Vlassa, Marioara Moldovan, Rahela Carpa Jan 2022

Chromatographic Profile Of Major Whey Proteins In Some Dairy Beverages Based On Milk Serum, Doina Prodan, Miuta Filip, Mihaela Vlassa, Marioara Moldovan, Rahela Carpa

Turkish Journal of Chemistry

The aim of this study was the determination of chromatographic profiles of major whey proteins (WP): α-lactalbumin (α-La), β-lactoglobulin A and B, (β-Lg A and B), bovine serum albumin (BSA) in dairy beverages based on Zonar milk serum. The studied WP were separated by high-performance liquid chromatography (HPLC) on Aeris XB-C18 column using gradient elution with 0.1% trifluoroacetic acid (TFA) in water and 0.1% TFA in 80% acetonitrile, at 214 nm detection. The HPLC method was validated for system suitability, selectivity/specificity, linearity (R2 ≥ 0.996), precision (RSD% ≤ 2.01), trueness (recovery 96.29%-102.08%), sensitivity (limits of quantification (LOQ) 1.35-10.08 μg/mL), …


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 …


Polyvinyl Alcohol-Citrate-Stabilized Silver Nanoparticles As An Optical Sensor For Selective Colorimetric Determination Of Sildenafil, Asi̇ye Aslihan Avan Jan 2022

Polyvinyl Alcohol-Citrate-Stabilized Silver Nanoparticles As An Optical Sensor For Selective Colorimetric Determination Of Sildenafil, Asi̇ye Aslihan Avan

Turkish Journal of Chemistry

A facile and sensitive colorimetric detection method for sildenafil citrate (SLDC) has been developed by using polyvinyl alcohol-citrate-stabilized silver nanoparticles (PVA-Cit-AgNPs). The sensitivity and selectivity of colorimetric detection were investigated in detail. The PVA-Cit-AgNPs could be induced to aggregate immediately in the presence of SLDC, especially after the addition of 0.1 M HCl solution. The SLD could be detected by the colorimetric response of AgNPs that could be monitored by a UV-Vis spectrophotometer or even the naked eye. The linear range was found to be 0.6-5.0 μM with the calculated detection limit of 0.1 μM and the naked-eye detection limit …


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+ …


Degradation Of Dye Containing In Textile Wastewater By Sequential Process: Photocatalytic And Biological Treatment, Jose Carlos Mendoza Hernandez, Gabriela Perez Osorio, Jose Eligio Moises Gutierrez Arias, Josefina Castañeda Camacho Jan 2022

Degradation Of Dye Containing In Textile Wastewater By Sequential Process: Photocatalytic And Biological Treatment, Jose Carlos Mendoza Hernandez, Gabriela Perez Osorio, Jose Eligio Moises Gutierrez Arias, Josefina Castañeda Camacho

Turkish Journal of Chemistry

In this research, a combined photocatalytic and biological treatment is proposed for the elimination of pollutants present in textile wastewater using a natural erionite zeolite (PE) and aluminum oxide (PA) synthesized by the sol-gel method as photocatalysts, and solar radiation. Both catalysts were characterized by XRD, SEM, and EDS. For biological treatment two bacterial consortium were used: BC1 (Escherichia coli N16, Serratia k120, Pseudomonas putida B03 and Enterobacter hormaechei), and consortium BC2 (Escherichia coli N16, Serratia Mc107, Enterobacter N9, Enterobacter hormaechei Mc9). The photocatalytic and microbiological treatments were carried out initially separately and subsequently in a …


Kinetic, Isotherm, And Thermodynamic Studies For Adsorptive Removal Of Basic Violet 14 From Aqueous Solution, Yasemi̇n Tamer, Hale Berber Jan 2022

Kinetic, Isotherm, And Thermodynamic Studies For Adsorptive Removal Of Basic Violet 14 From Aqueous Solution, Yasemi̇n Tamer, Hale Berber

Turkish Journal of Chemistry

In this study, the performance of chitosan based semi-IPN nanocomposite hydrogels for the adsorptive removal of basic violet 14 (BV14) from aqueous solution has been explored. Batch adsorption studies were conducted to determine the effect of various parameters on BV14 adsorption, and optimum values were reported as pH of 8, the adsorbent dosage of 0.025 g, initial BV14 concentration of 5 mg L-1 and contact time of 90 min at a temperature of 25 °C. The semi-IPN hydrogel containing 0.5% by weight GO showed the improved adsorption capacity for BV14 compared to the neat hydrogel adsorbent, and the maximum …


Quaternarization And Polymerization Of 2-Chloroethyl Maleate Derivative Of Epoxidized Soybean Oil, Demet Gürbüz Jan 2022

Quaternarization And Polymerization Of 2-Chloroethyl Maleate Derivative Of Epoxidized Soybean Oil, Demet Gürbüz

Turkish Journal of Chemistry

As a potent antibacterial, antifungal or antiviral material, synthesis of quaternarized epoxidized soybean oil was demonstrated in this work. The first step of the synthesis is the reaction of epoxidized soybean oil (ESO) with 2-chloroethyl maleic acid (Cl-MA-ESO). The last step is quaternarization of this condensate with triethylamine (Q-MA-ESO). All the synthesized monomers were characterized by FTIR and 1H NMR techniques. Homopolymer of the quaternarized derivative (Q-MA-ESO) was not obtained. However, styrene copolymers were obtained and characterized. Thermal properties of the copolymers were determined by TGA and DSC techniques. Additionally, swelling properties of the materials were also evaluated. The …


Removal Of Polycyclic Aromatic Hydrocarbons (Pahs) From Water Through Degradable Polycaprolactone Electrospun Membrane, Fuat Topuz Jan 2022

Removal Of Polycyclic Aromatic Hydrocarbons (Pahs) From Water Through Degradable Polycaprolactone Electrospun Membrane, Fuat Topuz

Turkish Journal of Chemistry

Polycyclic aromatic hydrocarbons (PAHs) are common and persistent environmental pollutants produced during the incomplete combustion of fuels. They are known for their carcinogenic and mutagenic properties. Thus, their removal from water bodies is highly crucial and has become a critical issue globally. As a solution, here an electrospun polycaprolactone (PCL) membrane with a mean fiber diameter of 2.74 ± 1.3 μm was produced by electrospinning. Water contact angle (WCA) analysis confirmed the hydrophobic nature of the PCL membrane with a WCA of 124°, which remained stable over time. Differential scanning calorimetry analysis (DSC) revealed the semicrystalline nature of the membrane …


The Relation Between Surface Acidity And Moo3:Al2o3 Ratio On The Ternary Mixed Oxide Catalysts For The Conversion Of Propan-2-Ol, Hani Zeidan, Ebru Erünal, Mustafa Esen Marti Jan 2022

The Relation Between Surface Acidity And Moo3:Al2o3 Ratio On The Ternary Mixed Oxide Catalysts For The Conversion Of Propan-2-Ol, Hani Zeidan, Ebru Erünal, Mustafa Esen Marti

Turkish Journal of Chemistry

In this study, ternary mixed oxide catalysts containing Al2O3-MoO3-MgO and Al2O3-MoO3-WO3 were prepared with a changing ratio of MoO3:Al2O3 between 0.05 and 20.00. All catalysts showed 100% selectivity towards propene during the conversion of propan-2-ol at temperatures between 220 and 400 °C. The catalysts prepared from WO3 possessed very strong acid sites, which cause higher catalytic activity than catalysts prepared from MgO. Besides, the ratio of MoO3:Al2O3 was found to be directly proportional to the conversion …


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 …


Gold Nanoparticles/Over-Oxidized Poly-Eriochrome Black T Film Modified Electrode For Determination Of Arsenic, Mürşi̇de Ceren Afşar, Aydan Elçi̇, Zekerya Dursun Jan 2022

Gold Nanoparticles/Over-Oxidized Poly-Eriochrome Black T Film Modified Electrode For Determination Of Arsenic, Mürşi̇de Ceren Afşar, Aydan Elçi̇, Zekerya Dursun

Turkish Journal of Chemistry

A glassy carbon electrode, modified with gold nanoparticles/over-oxidized poly-eriochrome black T film, was fabricated for sensitive determination of As(III) by stripping voltammetry in an acidic medium. The electrode surface properties were characterized by cyclic voltammetry, electrochemical impedance spectroscopy, scanning electron microscope (SEM), and X-ray photoelectron spectroscopy (XPS). The electrode demonstrated a good response towards As(III), with a detection of 0.077 μM and good linearity in the range of 0.1 to 10 μM (R2 = 0.9977). For the determination of As(III), the fabricated electrode was placed in different mineral water samples, acidified with 0.75 M HCl solution, spiked with various …


Investigation Of Antibacterial And Photocatalytic Efficiency Of Green Zno Nanoparticles That Synthesized With Celosia Cristata Flower Extract, Mahmure Özgür, Özgür Duygulu, Melda Altikatoğlu Yapaöz Jan 2022

Investigation Of Antibacterial And Photocatalytic Efficiency Of Green Zno Nanoparticles That Synthesized With Celosia Cristata Flower Extract, Mahmure Özgür, Özgür Duygulu, Melda Altikatoğlu Yapaöz

Turkish Journal of Chemistry

Increasing interest in green chemistry has led scientists to an environmentally friendly nanoparticle synthesis approach that has many advantages, such as simple, affordable and versatility for a wide range of commercial production. In this study, green synthesis of zinc oxide nanoparticles (ZnO NPs), which is widely researched in the field of nanotechnology, was performed under different conditions (volume ratio of CC flower extract to Zn(CH3COO)2 solution, time, pH and temperature) using the aqueous extract of Amarant (Celosia cristata L., CC, cockscome) plant flowers. Produced ZnO NPs were characterized by UV-Vis absorption spectroscopy, Fourier transform infrared spectroscopy (FTIR), high-resolution transmission electron …


Preparation, Assessment, And Swelling Study Of Amphiphilic Acrylic Acid/Chitosan-Based Semi-Interpenetrating Hydrogels, Mohammad Reza Jozaghkar, Amir Sepehrianazar, Farshid Ziaee, Fakhrosadat Mirtaleb Jan 2022

Preparation, Assessment, And Swelling Study Of Amphiphilic Acrylic Acid/Chitosan-Based Semi-Interpenetrating Hydrogels, Mohammad Reza Jozaghkar, Amir Sepehrianazar, Farshid Ziaee, Fakhrosadat Mirtaleb

Turkish Journal of Chemistry

The aim of this study was to synthesize amphiphilic semi-IPN hydrogels based on acrylic acid (AA) and chitosan (CS) using AIBN as an initiator and N,N?methylene bis acrylamide as a crosslinking agent. The swelling behavior of the hydrogels was evaluated at a variety of pH values, temperature, the salinity of media and time, and the swelling mechanism was investigated using Fickian diffusion and Schott's 2nd-order-kinetics models. FTIR spectroscopy was used to confirm the synthesis of AA/CS hydrogel. The swelling results showed that, in the acidic media, as the CS content increase the hydrogel swelling ratio reduces. It was found that …


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 …


A Review On The Achievement Of Enzymatic Glycerol Carbonate Production, Selda Aydoğdu, Nurcan Kapucu Jan 2022

A Review On The Achievement Of Enzymatic Glycerol Carbonate Production, Selda Aydoğdu, Nurcan Kapucu

Turkish Journal of Chemistry

High energy demand driven by decreasing fossil fuels, and global warming because of the burning of fossil fuels necessitates the utilization of renewable and clean energy. One of these renewable energy sources is biodiesel. The increasing trend of biodiesel over the last 20 years tends to result in increasing glycerol (Gly), which is produced during the biodiesel production in 10% ratio (w/w) as a by-product. Using Gly as raw material is an alternative way to produce bio-based new products such as glycerol carbonate (GlyC). GlyC is a value-added product of Gly/vegetable oil and this product can be used as a …


Homonuclear Nickel(Ii) Metal-Organic Framework-Type Supramolecule: Adsorption And Emission Properties, Idongesit Mbonu, Olusegun Abiola, Hamzah Bawa Jan 2022

Homonuclear Nickel(Ii) Metal-Organic Framework-Type Supramolecule: Adsorption And Emission Properties, Idongesit Mbonu, Olusegun Abiola, Hamzah Bawa

Turkish Journal of Chemistry

Coordination-driven self-assembly of nickel (II) ions with equimolar amounts of 1, 10 phenanthroline, and benzoic acid was used to create homonuclear nickel (II) MOF-type supramolecule. Single crystal X-ray diffraction, scanning electron microscopy, differential scanning calorimetry, photoluminescence measurement, FT-IR, UV-visible spectroscopy, and nitrogen physisorption measurement were used to characterize the compound. The single crystal X-ray diffraction study reveals that the synthesized compound is two-dimensional with pores in the structure. The homonuclear nickel (II) MOF-type supramolecule crystallized in a triclinic crystal system, with space group P-1 (No.2) and unit cell parameters a = 9.2053(4) Ǻ, b = 13.2964(5) Ǻ, c = 15.8998(6) …


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 …


Photocatalytic Degradation Of Paracetamol By Semiconductor Oxides Under Uv And Sunlight Illumination, Derman Akşi̇t, Güli̇n Selda Pozan Soylu Jan 2022

Photocatalytic Degradation Of Paracetamol By Semiconductor Oxides Under Uv And Sunlight Illumination, Derman Akşi̇t, Güli̇n Selda Pozan Soylu

Turkish Journal of Chemistry

In this study, photocatalytic degradation of paracetamol (acetaminophen), an analgesic and antipyretic drug, was investigated in using semiconductors under UV-B and sunlight irradiation. Semiconductor materials, Bi2O3, ZnO, TiO2, and ZrO2, were prepared using simple sol-gel, coprecipitation, and microwave synthesis methods. These photocatalyts were characterized by various spectroscopic and other techniques. As a result of the reactions, 25 ppm paracetamol with Bi2O3 and ZnO photocatalyst, total degradation was achieved with UV-B irradiation in 90 min. The results of photocatalytic activities showed that the highest degradation rate was obtained with 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 …


Prof. Dr. O. Yavuz Ataman, Ahmet Emi̇n Eroğlu Jan 2021

Prof. Dr. O. Yavuz Ataman, Ahmet Emi̇n Eroğlu

Turkish Journal of Chemistry

Prof. Dr. O. Yavuz Ataman passed away on August 15, 2020, in Ankara. He was an academic as well as a social figure throughout his life. He had remarkable achievements in academy as a researcher, an educator, and an administrator. He was known for his unique approaches to the events in all aspects of life. With his beloved character, he was really special. With Prof. Ataman?s passing away, the chemistry and especially analytical chemistry community have lost a very special member.


Process Optimization And Mechanism Study Of Acid Red G Degradation By Electro-Fentonfeox Process As An In Situ Generation Of H2o2, Hailong Sun, Yingwu Yao, Feng Wei, Qiang Zhao, Baichen Liu, Liman Zhang Jan 2021

Process Optimization And Mechanism Study Of Acid Red G Degradation By Electro-Fentonfeox Process As An In Situ Generation Of H2o2, Hailong Sun, Yingwu Yao, Feng Wei, Qiang Zhao, Baichen Liu, Liman Zhang

Turkish Journal of Chemistry

Dye-contaminated wastewaters are industrial wastewaters that are difficult to treat using traditional biochemical and physicochemical methods. In the present work, the acid red G was removed as a model pollutant by the electro-Fenton process for the first time. The anode and cathode used by the electro-Fenton process were iron plate and graphite felt, respectively. It was concluded that under the optimal conditions of current density = 20 mA cm-2, pH = 3 and initial Na2SO4 concentration = 0.2 M, the removal rate of acid red G (ARG) with an initial concentration of 300 mg L-1 could reach 94.05% after 80 …


Synthesis Of Nonperipherally Tetra-[5-(Diethylamino)-2-Formylphenoxy] Substituted Metallophthalocyanines And Their Electrochemistry, Turgut Keleş, Di̇lek Ünlüer, Zekeri̇ya Biyiklioğlu, Yasemi̇n Ünver Jan 2021

Synthesis Of Nonperipherally Tetra-[5-(Diethylamino)-2-Formylphenoxy] Substituted Metallophthalocyanines And Their Electrochemistry, Turgut Keleş, Di̇lek Ünlüer, Zekeri̇ya Biyiklioğlu, Yasemi̇n Ünver

Turkish Journal of Chemistry

3-[5-(diethylamino)-2-formylphenoxy]phthalonitrile (n-TY-CN), metallophthalocyanines n-TY-Co, n-TY-Cu, and n-TY-Mn bearing [5-(diethylamino)-2-formylphenoxy] groups at nonperipheral positions were prepared for the first time. These compounds were characterized with IR, NMR (only for n-TY-CN), mass and UV-vis (except n-TY-CN) spectroscopy. Voltammetric characterizations of n-TY-Co, n-TY-Cu, and n-TY-Mn revealed that while n-TY-Co, n-TY-Cu, and n-TY-Mn showed characteristic Pc ring and/or metal-based reduction reaction, n-TY-Co, n-TY-Cu, and n-TY-Mn were coated on the working electrode during the oxidation processes owing to the cationic electropolymerizations of the [5-(diethylamino)-2-formylphenoxy] substituents.


Validation Of Hplc Method For The Determination Of Chemical And Radiochemical Purity Of A 68ga-Labelled Euk-Sub-Kf-(3-Iodo-Y-) Dotaga, Ayşe Uğur, Şükrü Gökhan Elçi̇, Doğangün Yüksel Jan 2021

Validation Of Hplc Method For The Determination Of Chemical And Radiochemical Purity Of A 68ga-Labelled Euk-Sub-Kf-(3-Iodo-Y-) Dotaga, Ayşe Uğur, Şükrü Gökhan Elçi̇, Doğangün Yüksel

Turkish Journal of Chemistry

The prostate-specific membrane antigen (PSMA) represents an ideal biomarker for molecular imaging. Various PSMA-targeted radioligands are available for prostate cancer imaging. In this study, labeling of PSMA I&T with 68Ga, as well as validation of the radiochemical purity of the synthesis product by reverse phase radio high-performance liquid chromatography (HPLC) method are intended. Since the standard procedure for the quality control (QC) was not available, definition of chemical and radiochemical purity of 68Ga-PSMA I&T was carried out according to the Q2 (R1) ICH guideline. The standard QC tests were analyzed with Scintomics 8100 radio-HPLC system equipped with a radioactivity detector. …


Comparison Of Clinically Approved Molecules On Sars-Cov-2 Drug Target Proteins: A Molecular Docking Study, Hasan Çubuk, Mehmet Özbi̇l Jan 2021

Comparison Of Clinically Approved Molecules On Sars-Cov-2 Drug Target Proteins: A Molecular Docking Study, Hasan Çubuk, Mehmet Özbi̇l

Turkish Journal of Chemistry

The new type of coronavirus, SARS-CoV-2 has affected more than 22.6 million people worldwide. Since the first day the virus was spotted in Wuhan, China, numerous drug design studies have been conducted all over the globe. Most of these studies target the receptor-binding domain of spike protein of SARS-CoV-2, which is known to bind to the human ACE2 receptor and SARS-CoV-2 main protease, vital for the virus' replication. However, there might be a third target, human furin protease, which cleaves the virus' S1-S2 domains playing an active role in its entry into the host cell. In this study, we docked …


Synthesis Of 7,12-Bis(4-(Di(1h-Pyrrol-2-Yl)Methyl)Phenyl)Benzo[K]Fluoranthene From Anew Dialdehyde As A Novel Fluorometric Bis-Dipyrromethane Derivative, Faride Ranjbari, Salar Hemmati, Mohammad Reza Rashidi Jan 2021

Synthesis Of 7,12-Bis(4-(Di(1h-Pyrrol-2-Yl)Methyl)Phenyl)Benzo[K]Fluoranthene From Anew Dialdehyde As A Novel Fluorometric Bis-Dipyrromethane Derivative, Faride Ranjbari, Salar Hemmati, Mohammad Reza Rashidi

Turkish Journal of Chemistry

Dipyrromethanes are useful mediator structures which can be used as a part of other molecules such as bis-porphyrins and their derivations. Various methods have been developed for their synthesis. This study presents the synthesis of a new bis- dipyrromethane, 7,12-bis(4-(di(1H-pyrrol-2-yl)methyl)phenyl)benzo[k]fluoranthene, using the Lewis acid catalyzed reaction between a new dialdehyde and pyrrole at room temperature. The UV spectroscopic and fluorometric properties of the final product and precursors were determined. The newly synthesized product with desirable UV spectroscopic and fluorometric properties has the potential to be applied as a part of bisporphyrins or it can be used for other purposes in …


In Situ Preparation Of Hetero-Polymers/Clay Nanocomposites By Cuaac Click Chemistry, Mehmet Ati̇lla Taşdelen, Çağatay Altinkök Jan 2021

In Situ Preparation Of Hetero-Polymers/Clay Nanocomposites By Cuaac Click Chemistry, Mehmet Ati̇lla Taşdelen, Çağatay Altinkök

Turkish Journal of Chemistry

A series of polymer/clay nanocomposites containing mechanistically two different polymers, poly(ethylene glycol) (PEG) and poly(epsilon caprolactone) (PCL), were prepared by simultaneous copper(I)-catalyzed alkyne-azide cycloaddition click reactions. Both clickable polymers, PEG-Alkyne and PCL-Alkyne, were simultaneously clicked on to azide-functional montmorillonite (MMT-N3) nanoclay to get corresponding PEG-PCL/MMT nanocomposites. The chemical structures of the resulting nanocomposites were verified by following azide and silicone-oxygen bands using FT-IR and characteristic bands of PEG and PCL segments using 1H-NMR spectroscopy. The combined XRD and TEM analysis confirmed that all PEG-PCL/MMT nanocomposites had partially exfoliated/ intercalated morphologies. In addition, the increase of MMT-N3 loading not only improved …