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Full-Text Articles in Physical Sciences and Mathematics

Synthesis, Predictions Of Drug-Likeness, And Pharmacokinetic Properties Of Some Chiral Thioureas As Potent Enzyme Inhibition Agents, Yusuf Sicak Jan 2022

Synthesis, Predictions Of Drug-Likeness, And Pharmacokinetic Properties Of Some Chiral Thioureas As Potent Enzyme Inhibition Agents, Yusuf Sicak

Turkish Journal of Chemistry

A series of chiral thioureas (1 - 17) were synthesized from and tested for their anticholinesterase, tyrosinase, and urease enzyme inhibitor activities. Various phenylisothiocyanates were added to solution of L-cysteine in methanol: water (1 : 1 v / v) at room temperature and stirred for 24 h. The precipitated solid was recrystallized from n-butanol. Pure compounds were characterized by NMR (1H and 13C), FTIR, and CHNS. Tertiary amine containing N-(4-(diethylamino)phenyl)-N'-(2-mercapto-carboxyethanyl)thiourea 17, N-(4-(dimethylamino)phenyl)-N'-(2-mercapto-carboxyethanyl)thiourea 16 and trimethoxy containing N-(3,4,5-trimethoxyphenyl)-N'-(2-mercapto-carboxyethanyl)thiourea 14 were more active than galantamine against AChE and BChE enzymes. In tyrosinase enzyme inhibition activity, compound 14, 10, 12, 6, 13, and …


Selective Hydrogenation Of Diphenylacetylene Using Nico Nanoparticles Supported On Mesoporous Carbon As Catalyst, Alyaa Shiddiqah, Iman Abdullah, Yuni Krisnandi Jan 2022

Selective Hydrogenation Of Diphenylacetylene Using Nico Nanoparticles Supported On Mesoporous Carbon As Catalyst, Alyaa Shiddiqah, Iman Abdullah, Yuni Krisnandi

Turkish Journal of Chemistry

Hydrogenation of alkynes to alkenes is an important procedure in the synthesis of organic compounds. In this study, selective hydrogenation was carried out on diphenylacetylene as a model of alkyne compounds using NaBH4 as a hydrogen source and NiCo bimetallic nanoparticles supported on mesoporous carbon (NiCo/MC) as a catalyst. The mesoporous carbon was prepared using the soft-templated method from phloroglucinol and formaldehyde as precursors while the NiCo/MC catalyst was synthesized using a wet impregnation method. Based on surface area analysis, it was found that the pore diameters of MC, Ni/MC, and NiCo/MC were 12.8 nm, 13.4 nm, and 12.7 nm …


Computational Investigation Of Unsaturated Ketone Derivatives As Mao-B Inhibitors By Using Qsar, Adme/Tox, Molecular Docking, And Molecular Dynamics Simulations, Abdellah El Aissouq, Mohammed Bouachrine, Abdelkrim Ouammou, Fouad Khalil Jan 2022

Computational Investigation Of Unsaturated Ketone Derivatives As Mao-B Inhibitors By Using Qsar, Adme/Tox, Molecular Docking, And Molecular Dynamics Simulations, Abdellah El Aissouq, Mohammed Bouachrine, Abdelkrim Ouammou, Fouad Khalil

Turkish Journal of Chemistry

Unsaturated ketone derivatives are known as monoamine oxidase B (MAO-B) inhibitors, a potential drug target for Parkinson?s disease. Here, molecular modeling studies, including 2D-QSAR, ADMET prediction, molecular docking, and MD simulation, were performed on a new series of MAO-B inhibitors. The objective is to identify new MAO-B inhibitors with high inhibitory efficacy. The developed 2D-QSAR model was based on the descriptors of MOE software. The most appropriate model, using the partial least squares regression (PLS regression) method, yielded 0.88 for the determination coefficient (r2), 0.28 for the root-mean-square error (RMSE), and 0.2 for the mean absolute error (MAE). The predictive …


Synthesis Of A Novel Antiweathering Nanocomposite Superhydrophobic Room Temperaturevulcanized (Rtv) Silicon Rubber Enhanced With Nanosilica For Coating High Voltageinsulators, Khalid K. Abbas, Mayyadah S. Abed, Ali F. Jasim Jan 2022

Synthesis Of A Novel Antiweathering Nanocomposite Superhydrophobic Room Temperaturevulcanized (Rtv) Silicon Rubber Enhanced With Nanosilica For Coating High Voltageinsulators, Khalid K. Abbas, Mayyadah S. Abed, Ali F. Jasim

Turkish Journal of Chemistry

A new nanocomposite superhydrophobic of the RTV (room temperature vulcanized) silicon rubber reinforced with a different percentage of nanosilica was prepared by a two-stage sol-gel route to obtain a superhydrophobic surface coating on high voltage glass insulator, preventing the dust-water droplet from adhering to its surface. The cold spraying technique was utilized to build up a thin nanocomposite superhydrophobic layer on the glass insulator containing different percentages of the nanosilica particles, such as 23 wt %, 33 wt %, and 44 wt % with RTV silicon substrate. The synthesized nanocomposite was analyzed using the contact angle, roughness, adhesion, hardness, and …


An Experimental And Theoretical Analysis Of Supercritical Carbon Dioxide Extraction Of Cu(Ii) And Pb(Ii) Ions In The Form Of Dithizone Bidentate Complexes, Jeton Halili, Avni Berisha Jan 2022

An Experimental And Theoretical Analysis Of Supercritical Carbon Dioxide Extraction Of Cu(Ii) And Pb(Ii) Ions In The Form Of Dithizone Bidentate Complexes, Jeton Halili, Avni Berisha

Turkish Journal of Chemistry

For more than five decades, dithizone has been widely used as an analytical reagent. This ligand forms strongly colored complexes with metal ions and this ability to form complexes can be used for extraction/removal of certain metal ions in addition to analytical determination. In static mode, the supercritical carbon dioxide extraction of copper and lead ions from aqueous solutions after complexation by the dithizone ligand is studied (at two different conditions: a) p = 120 bar, T = 30 °C, and b) p = 72 bar, T = 50 °C). The addition of methanol improved the extraction process by modulating …


Catalytic Activity Of Ethylbenzene With Product Selectivity By Gold Nanoparticlessupported On Zinc Oxide, Afiq Anwar, Azman Ma'amor, H.N.M. Ekramul Mahmud, Wan Jefrey Basirun, Iskandar Abdullah Jan 2022

Catalytic Activity Of Ethylbenzene With Product Selectivity By Gold Nanoparticlessupported On Zinc Oxide, Afiq Anwar, Azman Ma'amor, H.N.M. Ekramul Mahmud, Wan Jefrey Basirun, Iskandar Abdullah

Turkish Journal of Chemistry

The oxidation of ethylbenzene (EB) using tert-butyl hydroperoxide as the oxidizing agent was carried out in presence of gold nanoparticles (3 nm) supported on zinc oxide in acetonitrile solution. A higher selectivity towards acetophenone (ACP) as the major product, and a moderate selectivity towards other products such as 1-phenylethanol (PE), benzaldehyde (BZL), and benzoic acid (BzA) were observed using the prepared Au/ZnO nanocatalysts at 100 °C for 24 h. It is suggested the reaction produces an intermediate product, which is dimethylethyl-1-phenylethyl peroxide through a radical mechanism. A small amount of benzaldehyde was observed because benzaldehyde went autoxidation to form benzoic …


Removal Of Cd2+ Metal Ions From Aqueous Solutions By Na-Alginate-Containingcomposite Biosorbent, Ramazan Donat Jan 2022

Removal Of Cd2+ Metal Ions From Aqueous Solutions By Na-Alginate-Containingcomposite Biosorbent, Ramazan Donat

Turkish Journal of Chemistry

This research is related to the effect of alginate-containing composite biosorbent on the sorption capacity of heavy metal Cd2+ ions. The study aims to determine the character and optimization of the sorption of Na-alginate-containing composite biosorbent on the sorption of heavy metal Cd2+ metal ions in an aqueous solution. Optimum conditions of parameters such as biosorbent amount, pH value effect, concentration effect, contact time, and temperature that affect the sorption of Cd2+ ions were determined. Langmuir, Freundlich, D-R isotherms were applied to the obtained data, and it was noted that the sorption Cd2+ ions are better explained with Freundlich and …


Synthesis Of 2-Aryl-5-(Arylsulfonyl)-1,3,4-Oxadiazoles As Potent Antibacterial Andantioxidant Agents, S N Murthy Boddapati, Subrahmanyam Talari, A Emmanuel Kola, Bhuvaneswari Chalapaka Jan 2022

Synthesis Of 2-Aryl-5-(Arylsulfonyl)-1,3,4-Oxadiazoles As Potent Antibacterial Andantioxidant Agents, S N Murthy Boddapati, Subrahmanyam Talari, A Emmanuel Kola, Bhuvaneswari Chalapaka

Turkish Journal of Chemistry

Ten novel 2-aryl-5-(arylsulfonyl)-1,3,4-oxadiazoles were produced and assessed for their in vitro antibacterial and antioxidant activities. Diverse spectroscopic methods li1H NMR, 13C NMR, IR, and LCMS were used for the characterization of the prepared samples and all the data was in good agreement with the anticipated structures. The prepared compounds 6a-j were screened for their in vitro antibacterial activity against bacterial strains Pseudomonas aeruginosa, Enterobacter aerogenes, Escherichia coli (grampositive), and Bacillus cerus, Staphylococcus aureus, Bacillus subtilis (gram-negative). The antimicrobial screening outcome revealed that the prepared 2-(3,4-dimethylphenyl)-5-tosyl-1,3,4-oxadiazole (6j), 2-(3-isopropylphenyl)-5-tosyl-1,3,4-oxadiazole (6c), and 2-(2-ethylphenyl)-5-tosyl-1,3,4-oxadiazole (6i) are most potent among all the examined compounds. Furthermore, …


Ultrafiltration-Based Sample Preparation And Hplc-Uv Determination Of Diclofenac In Human Plasma Samples, Merve Nenni̇, Ayşegül Doğan, Mustafa Çelebi̇er, Murat Soyseven, Mustafa Si̇nan Kaynak, Hassan Y. Aboul-Enein, Göksel Arli̇ Jan 2022

Ultrafiltration-Based Sample Preparation And Hplc-Uv Determination Of Diclofenac In Human Plasma Samples, Merve Nenni̇, Ayşegül Doğan, Mustafa Çelebi̇er, Murat Soyseven, Mustafa Si̇nan Kaynak, Hassan Y. Aboul-Enein, Göksel Arli̇

Turkish Journal of Chemistry

The sample preparation step is the initial step in pharmaceutical analysis. While ultrafiltration is a well-known technique used in the food and pharmaceutical industries, it has rarely been used to measure the plasma concentration of active pharmaceutical ingredients. This study aimed to analyze diclofenac sodium (DS) in human plasma samples using ultrafiltration-based sample preparation before high-performance liquid chromatography (HPLC) analysis. The advantages and limitations of ultrafiltration-based sample preparation in bioanalysis were evaluated by comparing the results with conventional methods. The precipitating agent was used before ultrafiltration. The analysis was carried on an HPLC-UV system with a C18 column (250 ×4.6 …


Induction Of Lutein Production In Scenedesmus Obliquusunder Different Culture Conditions Prior To Its Semipreparative Isolation, Ayşegül Erdoğan, Ayça Büşra Karataş, Zeli̇ha Demi̇rel, Meltem Dalay Jan 2022

Induction Of Lutein Production In Scenedesmus Obliquusunder Different Culture Conditions Prior To Its Semipreparative Isolation, Ayşegül Erdoğan, Ayça Büşra Karataş, Zeli̇ha Demi̇rel, Meltem Dalay

Turkish Journal of Chemistry

Microalgae with their improved growth rates and accumulation of high-value-added products make their commercial production attractive. Among them, lutein, which is a carotenoid, plays a very important role due to its various applications in the food and pharmaceutical industry. Induction of its biosynthesis can be triggered by various stress conditions like light. In this study, three different light intensities (50,150 and 300 μmol photons/m2s) and aeration rates (1, 3, and 5 L/min) were utilized to induce the lutein biosynthesis and biomass productivity in Scenedesmus obliquus. Lutein was isolated by preparative chromatography using a semiprep C30 column (10 × 250 mm, …


Drug Delivery System For Controlled Release Of Empagliflozin From Alginate-Chitosannanocarrier System, Nasim Ramazanzadeh, Nosrat O. Mahmoodi Jan 2022

Drug Delivery System For Controlled Release Of Empagliflozin From Alginate-Chitosannanocarrier System, Nasim Ramazanzadeh, Nosrat O. Mahmoodi

Turkish Journal of Chemistry

biocompatible nanocarrier system was prepared in this research through the reaction of calcium alginate (CA) with chitosan (CS). The structure of developed nanocarriers (CS-CA) was characterized by thermogravimetric analysis (TGA), Fourier transforms infrared (FT-IR) spectroscopy, field emission scanning electron microscopy (FE-SEM), X-ray diffraction (XRD) atomic force microscopy (AFM), and transmission electron microscopy (TEM). Swelling properties of CS-CA and CA, and their ability for loading and in vitro release of empagliflozin (EMP) were also investigated. The results showed the higher loading capacity of CS-CA compared to CA. For both nanocarriers, the drug release was higher at neutral pH (7.4 and 6.8) …


A New Study Of Dynamic Mechanical Analysis And The Microstructure Of Polyurethanefoams Filled, Noureddine Boumdouha, Zitouni Safidine, Achraf Boudiaf Jan 2022

A New Study Of Dynamic Mechanical Analysis And The Microstructure Of Polyurethanefoams Filled, Noureddine Boumdouha, Zitouni Safidine, Achraf Boudiaf

Turkish Journal of Chemistry

Polyurethane foams have good shock-absorbing properties. This article discusses the study of the physical, dynamic analysis, and microstructure of filled polyurethane foams (PUR). We used mineral fillings nanoparticles of titanium dioxide (TiO2) and calcium carbonate (C1) to support and strengthen the foam cell structure to develop shock absorption and thermal resistance properties. Dynamic mechanical analysis (DMA) and compression tests compared the mechanic characterization results with different modelling approaches. For studies of physicochemical properties, we used differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA). We deduced the flame retardancy mechanism. It appears that a detailed description of the characteristics of viscosity …


Design, Synthesis, And In Vitro Antitumor Activity Of 6-Aryloxyl Substituted Quinazolinederivatives, Meixia Fan, Lei Yao Jan 2022

Design, Synthesis, And In Vitro Antitumor Activity Of 6-Aryloxyl Substituted Quinazolinederivatives, Meixia Fan, Lei Yao

Turkish Journal of Chemistry

Quinazoline derivatives are a class of important antitumor drugs known as small molecule inhibitors that include epidermal growth factor receptor (EGFR) inhibitors. Based on the structure of poziotinib, a series of 6-aryloxyl substituted quinazoline derivatives were designed and synthesized. The in vitro antitumor activities of the compounds were evaluated by the 3-(4,5-dimethyl-thiazol-2- yl)2,5-diphenyltetrazolium bromide (MTT) method using the human gastric cancer N87 (HER2), nonsmall-cell lung cancer H1975 (EGFRT790M/L858R), and A549 (EGFRWT) cell lines. The most promising compound 4m exhibited potent antitumoral activities with IC50 values of 6.3 nM and 7.5 nM for N87 and H1975 cell lines, respectively. Meanwhile, it …


Adsorption Of Dimethyl Disulfide Onto Activated Carbon Cloth, Fi̇rdevs Mert, Numan Hoda, Ayhan Topuz, Leyla Budama Akpolat, Emrah Eroğlu Jan 2022

Adsorption Of Dimethyl Disulfide Onto Activated Carbon Cloth, Fi̇rdevs Mert, Numan Hoda, Ayhan Topuz, Leyla Budama Akpolat, Emrah Eroğlu

Turkish Journal of Chemistry

Dimethyl disulfide (DMDS) has a specific unpleasant odour and is profoundly toxic with an odour threshold of around 7-12 ppb. In this study, the removal of DMDS was investigated by adsorption on activated carbon cloth (ACC) in the gas phase. Kinetics and isotherm studies were performed. Adsorption kinetics followed by GC-MS and the data were processed using different models. When correlation coefficients (R2) of linear regression analysis are analyzed, it is seen that the concordance of experimental data to the pseudo-second-order equation is quite good. Isotherm data have been examined using Freundlich, Temkin and Langmuir models. The regression coefficient (R2) …


Electroanalytical Investigation And Voltammetric Quantification Of Antiviral Drug Favipiravir In The Pharmaceutical Formulation And Urine Sample Using A Glassy Carbon Electrode In Anionic Surfactant Media, Zeynep Akca, Hande İzem Özok, Yavuz Yardim, Zühre Şentürk Jan 2022

Electroanalytical Investigation And Voltammetric Quantification Of Antiviral Drug Favipiravir In The Pharmaceutical Formulation And Urine Sample Using A Glassy Carbon Electrode In Anionic Surfactant Media, Zeynep Akca, Hande İzem Özok, Yavuz Yardim, Zühre Şentürk

Turkish Journal of Chemistry

This work describes the electrochemical investigation of a promising antiviral agent, favipiravir (FAV) utilizing a nonmodified glassy carbon (GC) electrode, along with a unique voltammetric approach that can determine FAV with a good degree of accuracy, speed, and cost-effectiveness. Using cyclic voltammetry, the compound demonstrated a single well-defined and an irreversible oxidation peak at approximately +1.12 V (vs. Ag/AgCl) in Britton-Robinson (BR) buffer at pH 10.0. The synergistic effect of anionic surfactant, sodium dodecyl sulfate (SDS) on the adsorption ability of GC electrode remarkably increased the sensitivity of the stripping voltammetric measurements of FAV. Employing square-wave adsorptive stripping voltammetry at …


Microwave-Assisted Rapid Conjugation Of Horseradish Peroxidase-Dextran Aldehyde With Schiff Base Reaction And Decolorization Of Reactive Blue 19, Mi̇that Çelebi̇, Zafer Ömer Özdemi̇r, Murat Topuzoğullari Jan 2022

Microwave-Assisted Rapid Conjugation Of Horseradish Peroxidase-Dextran Aldehyde With Schiff Base Reaction And Decolorization Of Reactive Blue 19, Mi̇that Çelebi̇, Zafer Ömer Özdemi̇r, Murat Topuzoğullari

Turkish Journal of Chemistry

Microwave irradiation has become a routine technique in homogeneous and effective heating in organic synthesis. However, its application in enzyme-containing reactions is limited since it can cause denaturation of the enzyme. In this study, we have briefly investigated the effect of microwave heating on the conjugation reaction of horseradish peroxidase (HRP) with aldehyde derivative of dextran (D-CHO). The reaction was irradiated by microwave at 50 °C for 5 min. The conjugate was confirmed via GPC, in which the conjugates of HRP and D-CHO coexist with free unbound HRP molecules. Activity studies of HRP revealed that there is a small decrease …


Microstructure And Ionic Conductivity Investigation Of Samarium Doped Ceria(Sm0.2ce0.8o1.9) Electrolytes Prepared By The Templating Methods, Di̇lara Güçtaş, Vedat Sariboğa, Mehmet Ali̇ Faruk Öksüzömer Jan 2022

Microstructure And Ionic Conductivity Investigation Of Samarium Doped Ceria(Sm0.2ce0.8o1.9) Electrolytes Prepared By The Templating Methods, Di̇lara Güçtaş, Vedat Sariboğa, Mehmet Ali̇ Faruk Öksüzömer

Turkish Journal of Chemistry

Sm0.2Ce0.8O1.9 (SDC20) electrolytes were synthesized with cellulose templating (CT) and PVA templating (PVAT) methods. Powder characteristics were examined using TG/DTA, XRD, and SEM. Pellets are sintered at various temperatures for different durations. Mean grain sizes were calculated from SEM micrographs using the linear intercept method. Grain growth behavior of the electrolytes was investigated and the dominant diffusion mechanism was examined. The grain growth activation energies were obtained for the first time for the mentioned electrolytes prepared by the mentioned methods. The ionic conductivities were calculated by electrochemical impedance spectroscopy. The highest ionic conductivity value was found to be 0.050 S …


Boric Acid And Schiff Base-Based Fluorescent Sensor For Detection Of L-Tryptophan In Milk And Bsa Samples, Ümran Duru Kamaci, Musa Kamaci Jan 2022

Boric Acid And Schiff Base-Based Fluorescent Sensor For Detection Of L-Tryptophan In Milk And Bsa Samples, Ümran Duru Kamaci, Musa Kamaci

Turkish Journal of Chemistry

In the present paper, the fluorescence sensor based on Schiff base and boric acid was developed for easy and rapid detection of L-tryptophan in different samples such as milk and bovine serum albumin. The photoluminescence intensity was measured by using fluorescent measurements and the results indicated that the developed fluorescent sensor was exhibited selective, sensitive, reliable determination against L-tryptophan, and a series of various analytes such as cations, amino acids, and organic compounds were used to investigate the selectivity of the fluorescent chemosensor. The limit of detection and linear range of the chemosensor were calculated as 0.82 μM, and 0.1?500 …


Effect Of Promoter Type And Synthesis Method On Catalytic Performance Of Fe-Mn Based Ft-Olefin Catalysts, Gamze Gümüşlü Gür, Özge Ati̇k Jan 2022

Effect Of Promoter Type And Synthesis Method On Catalytic Performance Of Fe-Mn Based Ft-Olefin Catalysts, Gamze Gümüşlü Gür, Özge Ati̇k

Turkish Journal of Chemistry

Direct production of light olefins, building blocks of chemical industry, can be attained by developing efficient catalysts for Fischer?Tropsch synthesis (FTS). The nature of FTS complicates the catalyst development process as the product distribution is affected by the components and the preparation methods of the catalyst. In this work, high-throughput (HT) methodology is employed to overcome this problem by testing many different catalyst formulations. Fast performance screening of 40 different α-Al2O3 supported Fe-Mn based catalysts promoted with Cu, K and Ni, using different impregnation agents, was performed in a HT test system at atmospheric pressure. Promising catalyst candidates identified by …


Electrically Conductive, Hydrophobic, Uv Protective And Lightweight Cotton Spunlace Nonwoven Fabric Coated With Reduced Graphene Oxide, Beki̇r Cenkkut Gülteki̇n Jan 2022

Electrically Conductive, Hydrophobic, Uv Protective And Lightweight Cotton Spunlace Nonwoven Fabric Coated With Reduced Graphene Oxide, Beki̇r Cenkkut Gülteki̇n

Turkish Journal of Chemistry

In this study, cotton spunlace nonwoven fabrics with four different basis weights were coated with graphene oxide (GO) by conventional dip coating method which is one of the most simple and effortless process in textile industry. The graphene oxide coated cotton nonwoven fabrics were immersed in an aqueous sodium dithionite solution in order to obtain reduced graphene oxide (RGO) coated cotton spunlace nonwoven fabrics. The obtained nonwoven fabrics became electrically conductive with very low surface electrical resistivity of 5.98 × 102 W/sq for the 70 g/m2 basis weight nonwoven fabric. The color measurements and reflectance spectrophotometry were performed in order …


Synthesis And Characterization Of Amino Sulfonic Acid Functionalized Graphene Oxide As A Potential Carrier For Quercetin, Ali Sadeghi, Mohammad Faeli, Mahmood Tajbakhsh, Abdolreza Abri, Monireh Golpour Jan 2022

Synthesis And Characterization Of Amino Sulfonic Acid Functionalized Graphene Oxide As A Potential Carrier For Quercetin, Ali Sadeghi, Mohammad Faeli, Mahmood Tajbakhsh, Abdolreza Abri, Monireh Golpour

Turkish Journal of Chemistry

In this investigation, a new nanocomposite as a nanocarrier based on functionalized graphene oxide was synthesized by reaction of tetraethylenepentamine and chlorosulfonic acid with functional groups on the surface of GO. The synthesized nanocomposite was characterized by FT-IR, XRD TGA, FE-SEM, EDAX, TEM, and AFM analysis. To explore the potential of nanocomposites in drug delivery, the loading and releases of quercetin as an anticancer drug were investigated. The result displayed that more than 90% of the drug was loaded on the nanocarrier and the release of the drug is depending on the pH of the environment such that the releases …


Co2 Absorption Into Primary And Secondary Amine Aqueous Solutions With And Without Copper Ions In A Bubble Column, Hamed Yousefzadeh, Cansu Güler, Can Erkey, Erdal Uzunlar Jan 2022

Co2 Absorption Into Primary And Secondary Amine Aqueous Solutions With And Without Copper Ions In A Bubble Column, Hamed Yousefzadeh, Cansu Güler, Can Erkey, Erdal Uzunlar

Turkish Journal of Chemistry

Chemical absorption of CO2 into aqueous amine solutions using a nonstirred bubble column was experimentally investigated. The performance of CO2 absorption of four different primary and secondary amines including monoethanolamine (MEA), piperazine (PZ), 2-piperidineethanol (2PE), and homopiperazine (HPZ) were compared. The effects of initial concentration of amine, the inlet mole fraction of CO2, and solution temperature on the rate of CO2 absorption and CO2 loading (mol CO2/mol amine) were studied in the range of 0.02-1 M, 0.10-0.15, and 25-40 °C, respectively. The effect of the presence of copper ions in the amine solution on CO2 loading was also studied. By …


Peg4000 Modified Liposomes Enhance The Solubility Of Quercetin And Improve The Liposome Functionality: In Vitro Characterization And The Cellular Efficacy, Gülen Meli̇ke Demi̇rbolat, Ömer Erdoğan, Gökni̇l Peli̇n Coşkun, Özge Çevi̇k Jan 2022

Peg4000 Modified Liposomes Enhance The Solubility Of Quercetin And Improve The Liposome Functionality: In Vitro Characterization And The Cellular Efficacy, Gülen Meli̇ke Demi̇rbolat, Ömer Erdoğan, Gökni̇l Peli̇n Coşkun, Özge Çevi̇k

Turkish Journal of Chemistry

Quercetin, a multifunctional therapeutic agent, is used in various types of cancer. However, its therapeutic effect is limited by virtue of poorly aqueous solubility and instability in the physiological medium. To overcome these limitations, we aimed (i) to design quercetin loaded liposomes with unlinked-PEG4000 with regard to not only surface modification but also solubility enhancement, and (ii) to investigate the antineoplastic effects on HeLa cells. PEG4000 increased the quercetin solubility 2.2 fold. PEG4000 modified liposomes displayed small particle size (254 ± 69 nm), low polydispersity index (0.236 ± 0.018), favorable zeta potential (-35.4 ± 0.6 mV), high quercetin encapsulation efficiency …


Synthesis Of Polydentate, Multi Metal Ion Sensing, Unsymmetrical Schiff Bases With Complimented Antifungal Activity, Saranya Dhasarathan, Selvaraj Shunmugaperumal, P. Kamatchi Selvaraj Jan 2022

Synthesis Of Polydentate, Multi Metal Ion Sensing, Unsymmetrical Schiff Bases With Complimented Antifungal Activity, Saranya Dhasarathan, Selvaraj Shunmugaperumal, P. Kamatchi Selvaraj

Turkish Journal of Chemistry

Polydentate, unsymmetrical, and multi metal ion sensing Schiff bases comprised of ferrocenecarboxaldehyde attached azomethine group at one side and aromatic aldehyde linked imine on the other side have been synthesized. Cumulative addition of different metal salts solution to receptors solution, changes the electronic spectra contrarily and for the addition of Cu2+ ions, generation of MLCT charge transfer band responsible for the coordination of metal ion with a receptor is observed. Electrochemical data (ΔEp) arrived from the cyclic voltammograms suggest a quasi-reversible process. The modest concentration of metal ions required for effective sensing by the sensory material is calculated from the …


Intake Of Divalent Copper And Nickel Onto Natural Zeolite From Aqueous Solutions: A Study In Mono- And Dicomponent Systems, Burak Teki̇n, Ünsal Açikel Jan 2022

Intake Of Divalent Copper And Nickel Onto Natural Zeolite From Aqueous Solutions: A Study In Mono- And Dicomponent Systems, Burak Teki̇n, Ünsal Açikel

Turkish Journal of Chemistry

In this study, the noncompetitive and competitive adsorption process of copper (II) and nickel (II) ions on the natural zeolite were examined in simulated wastewater in a batch system with respect to concentration, pH and temperature. Optimum pH values were found as 5,0 for adsorption of copper and nickel ions on the zeolite. The effect of initial concentration and ambient temperature on the yield of adsorption was examined at this pH value. The equilibrium adsorption data of Cu (II) and Ni (II) onto the zeolite were analyzed by the Langmuir's and Freundlich's isotherms, and the experimental metal uptake data fitted …


Thio-Schiff Bases Derived From 2,2'-Disulfanedianiline Via Nanocerium Oxide: Antimicrobial Effect And Antiproliferative Effects In Melanoma Cells, Aslihan Dalmaz, Sefa Durmuş, Görkem Dülger, Merve Alpay Jan 2022

Thio-Schiff Bases Derived From 2,2'-Disulfanedianiline Via Nanocerium Oxide: Antimicrobial Effect And Antiproliferative Effects In Melanoma Cells, Aslihan Dalmaz, Sefa Durmuş, Görkem Dülger, Merve Alpay

Turkish Journal of Chemistry

In this study, the synthesis of dimeric disulfide-Schiff bases was carried out using two methods. The structures of the obtained Schiff bases were elucidated by various spectroscopic methods as well as elemental analysis. The Schiff base derivative compounds (3a-6) were screened for in vitro antibacterial activity against multidrug-resistant microorganisms using microdilution method. All the tested compounds showed varying inhibition zones against the pathogens. According to MIC results, the compound 2 was shown strong inhibitory activity against all the tested microorganisms compared to antibiotics. In addition, all the tested compounds showed different antiproliferative effects on the melanoma cell line (B16F10). Our …


Comparison Of A Commercial Water-Gas Shift Catalyst And La Modified Cu-Based Catalysts Prepared By Deposition-Precipitation In Methanol Steam Reforming, Orhan Özcan, Ayşe Ni̇lgün Akin Jan 2022

Comparison Of A Commercial Water-Gas Shift Catalyst And La Modified Cu-Based Catalysts Prepared By Deposition-Precipitation In Methanol Steam Reforming, Orhan Özcan, Ayşe Ni̇lgün Akin

Turkish Journal of Chemistry

Herein, a performance analysis of La-doped copper-based catalysts (CuO/ZrO2/La-Al2O3) in methanol steam reforming (MSR) was conducted and compared with a commercial low temperature water-gas shift catalyst (HiFUEL W220) to produce H2 with low CO selectivity. The physicochemical properties of as-obtained catalysts were characterized by N2 adsorption, XRD, and ICP-OES. Effect of calcination temperature (750 oC and 1000 oC) on the properties of mixed oxide support (La-Al2O3) were discussed based on catalytic activity. The optimum conditions of H23O/CH3OH ratio (1.0-3.0), space-time ratio (WFA0) (40-120 kg s mol-1), and reaction temperature (180-310 oC) were evaluated by a parametric study using the commercial …


Oxygen Vacancies On Pd/Tio2 Are Detected At Low Pressures By Esr Spectroscopy At Ambient Temperatures, Deni̇z Üner, Meli̇s Yarar Jan 2022

Oxygen Vacancies On Pd/Tio2 Are Detected At Low Pressures By Esr Spectroscopy At Ambient Temperatures, Deni̇z Üner, Meli̇s Yarar

Turkish Journal of Chemistry

A low field benchtop electron spin resonance (ESR) (also referred to as electron paramagnetic resonance (EPR)) spectrometer is used to reveal paramagnetic centres such as oxygen vacancies and Ti+3 centres over 0.5%Pd/TiO2. The measurement was performed at room temperature after the sample was reduced in situ under mild hydrogen pressures and evacuated to P < 10-6 Torr. The measurement was possible due to a T1 compensation effect under vacuum: Correlation times at low pressures enabled sufficient line narrowing and detection of the ESR signal, justifying a method using benchtop spectrometers coupled to vacuum manifolds. The method justification was demonstrated using similar measurements performed on a reference compound, Mn(II) in plasticine: a measurement performed by saturation recovery technique revealed that T1 of the signal due to Mn(II) was smaller in vacuum than its atmosphere exposed counterpart. By applying vacuum, the ESR spectra of 0.5%Pd/TiO2 were collected at ambient temperatures, with features equivalent to the published data obtained at cryogenic temperatures.


Synthesis Of Novel Oxadiazole Derivatives And Their Cytotoxic Activity Against Various Cancer Cell Lines, Bi̇lgesu Onur Sucu, Eli̇f Beyza Koç Jan 2022

Synthesis Of Novel Oxadiazole Derivatives And Their Cytotoxic Activity Against Various Cancer Cell Lines, Bi̇lgesu Onur Sucu, Eli̇f Beyza Koç

Turkish Journal of Chemistry

Caffeic acid (CA), ferulic acid (FA) and caffeic acid phenethyl ester (CAPE) have a broad anticancer effect on various cell lines. In this study, nine ferulic and caffeic acid-based 1,2,4 and 1,3,4 oxadiazole molecular hybrids were synthesized and their cytotoxic activity was evaluated mainly against Glioblastoma (GBM) cell lines. Compounds 1 and 5 exhibited the highest inhibitory activity against three different GBM cell lines (LN229, T98G, and U87), without toxicity to healthy human mesenchymal stem cells (hMSC). In addition, their cytotoxicity was also evaluated against three additional cancer cell lines and more inhibitory results were found than GBM cell lines. …


Synthesis And Characterization Of An Electrochromic Copolymer Based On 9, 10-Di (Furan-2-Yl)Anthracene And 3,4-Ethylenedioxythiophene, Ali̇ Kalçik, Ari̇f Kivrak, Buket Çarbaş Jan 2022

Synthesis And Characterization Of An Electrochromic Copolymer Based On 9, 10-Di (Furan-2-Yl)Anthracene And 3,4-Ethylenedioxythiophene, Ali̇ Kalçik, Ari̇f Kivrak, Buket Çarbaş

Turkish Journal of Chemistry

In this study, a new copolymer, which is a combination of two chemical structure (9,10-di(furan-2-yl)anthracene and 3,4-ethylenedioxythiophene was synthesized via electrochemical synthesis methods in the electrolyte medium of 0.1 M TBAPF6/ ACN solution. PEDOT homopolymer was also electrosynthesized for comparator experiments of the polymer formations in the same medium. The characterizations of polymers were achieved with general optical and electrochemical characterization techniques. The corresponding electrochromic copolymer shows blue and lilac color in its neutral and oxidized states, respectively. The copolymer has an optical band gap of 1.65 eV and 24% optical contrast at 500 nm with a high coloration efficiency …