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Full-Text Articles in Physical Sciences and Mathematics

Modeling And Optimization Of Simultaneous Degradation Of Rhodamine B And Acid Red 14 Binary Solution By Homogeneous Fenton Reaction: A Chemometrics Approach, Nasrin Aliasgharlou, Morteza Bahram, Pezhman Zolfaghari, Naiemeh Mohseni Jan 2020

Modeling And Optimization Of Simultaneous Degradation Of Rhodamine B And Acid Red 14 Binary Solution By Homogeneous Fenton Reaction: A Chemometrics Approach, Nasrin Aliasgharlou, Morteza Bahram, Pezhman Zolfaghari, Naiemeh Mohseni

Turkish Journal of Chemistry

This study aimed to propose a mathematical method to investigate and optimize the simultaneous elimination process of multiple organic pollutants using the Fenton process. Hence, the treatment of rhodamine B (RB) and acid red 14 (AR14) dyes in their binary solution was studied. Multivariate curve resolution alternating least square (MCR-ALS), a novel chemometric method, was applied along with correlation constraints to resolute the UV-Vis spectrophotometric data, enabling quantification of investigated dyes despite a high spectral overlapping. Response surface methodology was adopted to assess the model and optimize individual and interactive effects of three independent factors (Fe$^{2+}$, H$_{2}$O$_{2}$ and initial pH) …


Effects Of Composition On Catalytic Activities Of Molybdenum Doped Platinum Nanoparticles, Aslihan Sümer Jan 2020

Effects Of Composition On Catalytic Activities Of Molybdenum Doped Platinum Nanoparticles, Aslihan Sümer

Turkish Journal of Chemistry

The physical and chemical properties of bimetallic nanoparticles can be optimized by tuning the particle composition. In this study, we identified CO adsorption and dissociation energetics on five Pt-Mo nanoparticles at different concentrations, the lowest energy Pt$_{7}$, Pt$_{6}$Mo, Pt$_{5}$Mo$_{2}$, Pt$_{4}$Mo$_{3}$, and Mo$_{7}$ clusters. We have shown that the CO adsorption and dissociation energies and preferred CO adsorption sites are largely dependent on the composition of the nanoparticles. As the Mo concentration increases, the strength of the C-O internal bond in the adsorption complex decreases, as indicated by a decrease in the C-O stretching frequency. Also, more Mo sites in the …


Photochromic And Fluorescence Properties Of Coumarin Fulgimides, Khamis Nassor Ally, Leyla Öztürk, Mahmut Köse Jan 2020

Photochromic And Fluorescence Properties Of Coumarin Fulgimides, Khamis Nassor Ally, Leyla Öztürk, Mahmut Köse

Turkish Journal of Chemistry

Four new fulgimides possessing a fluorescent coumarin unit were synthesized from the corresponding fulgides, and their photochromic as well as fluorescence properties were investigated. The open-ring forms of coumarin fulgimides were found to exhibit fluorescence in the visible region. Upon exposure to UV light, the fulgimides were transformed into the nonfluorescent closed-ring forms, which can be reverted to the initial fluorescent open-ring forms on exposure to visible light. The efficiency of quenching of fluorescence was as high as 95% at the photostationary state of UV irradiation.


Characterization, Mechanical, And Antibacterial Properties Of Nanofibers Derived From Olive Leaf, Fumitory, And Terebinth Extracts, Ni̇lşen Sünter Eroğlu, Suat Canoğlu, Meti̇n Yüksek Jan 2020

Characterization, Mechanical, And Antibacterial Properties Of Nanofibers Derived From Olive Leaf, Fumitory, And Terebinth Extracts, Ni̇lşen Sünter Eroğlu, Suat Canoğlu, Meti̇n Yüksek

Turkish Journal of Chemistry

In this study, nanofiber structures were obtained with convenient polymers (PVA [polyvinyl alcohol] and PCL [poly º-caprolactone]) derived from the herbal extracts of olive leaves, fumitory, and terebinth plants. Optimum nanofiber structures were identified by measuring viscosity and conductivity values and performing morphological analysis, characterization, and mechanical tests of the prepared solutions. The potential use for wound healing at the most efficient level was determined as a result of antibacterial analysis of the structures obtained. APT (PVA/terebinth) and BFO (PCL/fumitory) nanofibers had the thinnest diameter range and the highest strength values. In terms of the determination of antibacterial effects, nanofiber …


A Comparative Study On The Monovalent And Divalent Cation Separation Of Polymeric Films And Membranes From Salt Solutions Under Diffusion-Dialysis, Serkan Acar, Hacer Yeşi̇m Cengi̇z, Ayça Ergün, Eymen Konyali, Hüseyi̇n Deli̇göz Jan 2020

A Comparative Study On The Monovalent And Divalent Cation Separation Of Polymeric Films And Membranes From Salt Solutions Under Diffusion-Dialysis, Serkan Acar, Hacer Yeşi̇m Cengi̇z, Ayça Ergün, Eymen Konyali, Hüseyi̇n Deli̇göz

Turkish Journal of Chemistry

This study deals with selective separation of mono- and divalent cations from aqueous salt solutions using polymeric films based on polyethylene (PE) and polyamide6 (PA6), and two different commercial nanofiltration (NF) membranes. The diffusion rates (D) of ions (Na$^{+}$ and Ca$^{2+})$, separation factors ($\alpha )$ and ion rejections (R) of the films and NF membranes are examined comparatively as well as their surface morphology and hydrophilicity. It is observed that the diffusion rates of Na$^{+}$are in the range of 0.7-1.8 $\times $ 10$^{-8}$cm$^{2}$.s$^{-1\, }$in the decreasing order of PE $>$ NF90 $>$ NF270 $>$ PA6 while Ca$^{2+\, …


Fluorescent Sensing Platform For Low-Cost Detection Of Cu$^{\Mathbf{2+}}$ By Coumarin Derivative: Dft Calculation And Practical Application In Herbal And Black Tea Samples, Tahi̇r Savran, Abdurrahman Karagöz, Şükri̇ye Ni̇han Karuk Elmas, Duygu Aydin, Furkan Özen, Kenan Koran, Fatma Nur Arslan, Ahmet Orhan Görgülü, İbrahi̇m Yilmaz Jan 2020

Fluorescent Sensing Platform For Low-Cost Detection Of Cu$^{\Mathbf{2+}}$ By Coumarin Derivative: Dft Calculation And Practical Application In Herbal And Black Tea Samples, Tahi̇r Savran, Abdurrahman Karagöz, Şükri̇ye Ni̇han Karuk Elmas, Duygu Aydin, Furkan Özen, Kenan Koran, Fatma Nur Arslan, Ahmet Orhan Görgülü, İbrahi̇m Yilmaz

Turkish Journal of Chemistry

A fluorogenic probe based on a coumarin-derivative for Cu$^{2+}$ sensing in CH$_{3}$CN/H$_{2}$O media (v/v, 95/5, 5.0 \textmu M) was developed and applied in real samples. 3-(4-chlorophenyl)-6,7-dihydroxy-coumarin (MCPC) probe was obtained by synthetic methodologies and identified by spectral techniques. The probe MCPC showed remarkable changes with a ``turn-off'' fluorogenic sensing approach for the monitoring of Cu$^{2+}$ at 456 nm under an excitation wavelength of 366 nm. The response time of the probe MCPC was founded as only 1 min. The detection limit of the probe MCPC was recorded to be 1.47 nM. The binding constant and possible stoichiometric ratio (1:1) values …


Synthesis, Biological Evaluation Of Antioxidant-Antibacterial Activities And Computational Studies Of Novel Anthracene- And Pyrene-Based Schiff Base Derivatives, Ayşegül Gümüş, Veysi̇ Okumuş, Selçuk Gümüş Jan 2020

Synthesis, Biological Evaluation Of Antioxidant-Antibacterial Activities And Computational Studies Of Novel Anthracene- And Pyrene-Based Schiff Base Derivatives, Ayşegül Gümüş, Veysi̇ Okumuş, Selçuk Gümüş

Turkish Journal of Chemistry

Schiff base derivatives with anthracene- and pyrene-based units, A1-A6 and P1-P6 were synthesized (89%-99% yields). Schiff base derivatives were designed to possess an heterocyclic moiety on one side to enhance the coordination ability towards metals. To investigate the biological assay of the newly synthesized compounds, their DPPH (2,2-diphenyl-1-picrylhydrazyl) radical scavenging, metal chelating, reducing power, antibacterial and DNA binding activities were tested. A6 (63.1%) showed the maximum free radical scavenging activity among all. However, compound P3 at concentration of 200 \textmu g/mL possessed the highest metal chelating (45.8%) activity and power of reduction. In addition, P3 and A6 showed antibacterial activity …


Structural Insights Of Two Novel N-Acetyl-Glucosaminidase Enzymes Through In Silico Methods, Ari̇f Sercan Şahutoğlu, Hati̇ce Duman, Steven Alex Frese, Sercan Karav Jan 2020

Structural Insights Of Two Novel N-Acetyl-Glucosaminidase Enzymes Through In Silico Methods, Ari̇f Sercan Şahutoğlu, Hati̇ce Duman, Steven Alex Frese, Sercan Karav

Turkish Journal of Chemistry

EndoBI-1 and EndoBI-2 are two endo-β-N-acetylglucosaminidase isoenzymes that cleave N-N'-diacetylchitobiosyl moieties found in various types of native N-glycans. These N-glycans are indigestible by human infants and adults due to the lack of responsible glycosyl hydrolases and they act as selective prebiotics for a probiotic microorganism, Bifidobacterium longum subsp. infantis, in the large intestine. The selectivity and the thermostability of EndoBI-1 and EndoBI-2 suggest that these enzymes may be useful for many scientific and industrial applications. In this study, the growing numbers of homologous sequences in different databases were exploited in a comparative approach to investigate structural properties of EndoBI-1 and …


Fabrication And Characterization Of Boric Acid-Crosslinked Ethyl Cellulose And Polyvinyl Alcohol Films As Potential Drug Release Systems For Topical Drug Delivery, Nasrin Aliasgharlou, Farzin Asghari Sana, Saba Khoshbakht, Pezhman Zolfaghari, Hamed Charkhian Jan 2020

Fabrication And Characterization Of Boric Acid-Crosslinked Ethyl Cellulose And Polyvinyl Alcohol Films As Potential Drug Release Systems For Topical Drug Delivery, Nasrin Aliasgharlou, Farzin Asghari Sana, Saba Khoshbakht, Pezhman Zolfaghari, Hamed Charkhian

Turkish Journal of Chemistry

In this study, boric acid (BA) is employed as a crosslinking agent to improve the characteristics of two commonly used polymeric films, ethyl cellulose (EC) and polyvinyl alcohol (PVA), for topical drug delivery applications. The developed films are characterized by FTIR spectroscopy and SEM analysis. The results show that the surfaces of the prepared films are even and transparent, except for the BA-modified EC sample. The initial cumulative release for erythromycin (EM) is found to be 0.30 and 0.36 mg/mL for EC and PVA films, which drops to 0.25 and 0.20 mg/mL after BA crosslinking, respectively, after 1 h at …


Synthesis, Antioxidant And Antimicrobial Properties Of Novel Pyridyl-Carbonyl Thiazoles As Dendrodoine Analogs, Zafer Şahi̇n, Sevde Nur Bi̇lteki̇n, Leyla Yurttaş, Şeref Demi̇rayak Jan 2020

Synthesis, Antioxidant And Antimicrobial Properties Of Novel Pyridyl-Carbonyl Thiazoles As Dendrodoine Analogs, Zafer Şahi̇n, Sevde Nur Bi̇lteki̇n, Leyla Yurttaş, Şeref Demi̇rayak

Turkish Journal of Chemistry

Marine compound dendrodoine was first obtained from tunicate species (Dendrodo grossularia). It has a five-membered ring, namely, it is a heterocycle thiadiazole, which is found rarely in natural sources. Following its biological activities, novel analogs have been investigated recently. Synthesis of the analogs for this study is realized with uncommon thiazole closure, including methylene-carbonyl condensation. Structures are elucidated by NMR (1H, 13C) and HRMS spectrums. As an alkaloid derivative, antioxidant properties were evaluated with DPPH and FRAP assays and antimicrobial effect with microdilution method. Among the series, 3bc-3cf showed higher antioxidant activity than those having 3 or 4-pyridyl substituents. There …