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Extraction/Transportation Of Co2+ Metal Ions With Bis(2-Ethylhexyl) Phosphate Dissolved In Kerosene Using A Multidropped Liquid Membrane Technique, VOLKAN DEMİREL, RAMAZAN DONAT 2023 TÜBİTAK

Extraction/Transportation Of Co2+ Metal Ions With Bis(2-Ethylhexyl) Phosphate Dissolved In Kerosene Using A Multidropped Liquid Membrane Technique, Volkan Demi̇rel, Ramazan Donat

Turkish Journal of Chemistry

The transport properties of Co2+ ions from the aqueous donor phase to aqueous acceptor phase with the recently developed multidroplet liquid membrane (MDLM) extraction system were studied. This system serves as a continuous process for the transportation of ions and requires fewer reagents for starting and conducting the procedure. Moreover, the procedure results in fewer waste chemicals and mixtures in comparison to traditional extraction methods. During extraction, bis(2-ethylhexyl) phosphate (D2EHPA) was used as a carrier material and 5% potassium thiocyanate (KSCN) solution was used to obtain a colored complex for UV-Vis detection. By means of several experiments, the optimum D2EHPA …


Exploring The Photocatalytic And Photodynamic Effects Of Bodipy-Linked Titanium Dioxide Nanoparticles, SEDA DEMİREL TOPEL 2023 TÜBİTAK

Exploring The Photocatalytic And Photodynamic Effects Of Bodipy-Linked Titanium Dioxide Nanoparticles, Seda Demi̇rel Topel

Turkish Journal of Chemistry

This study aimed to investigate the photocatalytic and photodynamic actions of a 2,6-diiodinated-BODIPY (2,6-diI2-Bod) photosensitizer (PS) covalently linked to TiO2 nanoparticles (NPs). The TiO2 NPs were synthesized utilizing the hydrothermal technique, yielding an average particle size of 4–5 nm as ascertained by transmission electron microscopy and 6.4 nm as determined by dynamic light scattering measurements. The integration of the nonsoluble Bod PS to TiO2 NPs provided increased dispersibility in physiological media, making it more applicable to photodynamic therapy applications. Bod-TiO2 NPs exhibited moderate efficiency of 56.9% in singlet oxygen generation. Additionally, the photocatalytic behavior of the TiO2 NPs was evaluated …


Photophysical, Thermal, And Dft Studies On A Tetraaryl-Azadipyrromethene Ligand And Its Zinc(Ii) Complex, GÖKHAN SEVİNÇ 2023 TÜBİTAK

Photophysical, Thermal, And Dft Studies On A Tetraaryl-Azadipyrromethene Ligand And Its Zinc(Ii) Complex, Gökhan Sevi̇nç

Turkish Journal of Chemistry

An azadipyrromethene ligand (H1) and homoleptic zinc(II) (H1-Zn) complex were synthesized. The resulting structures were elucidated by NMR, FTIR, and HRMS techniques. The photophysical properties and effects of complexing the zinc(II) atom to azadipyrromethene ligands in solution were studied by means of UV-Vis absorption and fluorescence spectroscopy. Experimental findings were elucidated using density functional theory computations and interfragment charge transfer (IFCT) and electron-hole analyses. The fluorescence features were found to be negligible. The ligand molecule decayed at a rate of 3% while the complex decayed at 2% upon photoirradiation based on photostability experiments. The singlet oxygen quantum yields of the …


Quaternized Chitosan/Pva/Natural Bioactive Agent Electrospun Wound Scaffolds: Production, Characterization, And Investigation Of Release Kinetics, Ezgi Eren Belgin, CANKIZ GİZEM DELİBALTA 2023 TÜBİTAK

Quaternized Chitosan/Pva/Natural Bioactive Agent Electrospun Wound Scaffolds: Production, Characterization, And Investigation Of Release Kinetics, Ezgi Eren Belgin, Cankiz Gi̇zem Deli̇balta

Turkish Journal of Chemistry

Quaternized chitosan (HTCC) was synthesized and characterized to increase chitosan solubility. Then HTCC was electrospun with poly (vinyl alcohol) (PVA) and prepared natural bioactive agent (Calendula officinalis) extract was loaded onto fibers for wound scaffold applications. Morphological, structural, and mechanical characterization of the produced wound scaffolds was performed and their in vitro bioactive component release behavior was investigated. As a result, it was observed that the degree of quaternization of chitosan was 0.89, and synthesized HTCC was soluble in acidic, basic, alkaline media and could be electrospun with PVA in the presence of a natural bioactive agent. The presence of …


Phytochemical Investigation On The Aerial Parts Of Veratrum Versicolor F. Viride Nakai And Their Biological Activities, SEONG SU HONG, JAE YEON LEE, YEON WOO JEONG, JI EUN LEE, YUN-HYEOK CHOI, WONSIK JEONG, Eun-Kyung AHN, CHUN WHAN CHOI, IL HO AHN, JOA SUB OH 2023 TÜBİTAK

Phytochemical Investigation On The Aerial Parts Of Veratrum Versicolor F. Viride Nakai And Their Biological Activities, Seong Su Hong, Jae Yeon Lee, Yeon Woo Jeong, Ji Eun Lee, Yun-Hyeok Choi, Wonsik Jeong, Eun-Kyung Ahn, Chun Whan Choi, Il Ho Ahn, Joa Sub Oh

Turkish Journal of Chemistry

Veratrum spp. have traditionally been used in folk medicine to treat various pathologies. In this study, nine compounds, comprising one simple phenolic compound (1), three stilbenoids (2–4), and five flavonoids (5–9), were isolated from the aerial parts of Veratrum versicolor f. viride Nakai. The structures of these compounds were elucidated by spectroscopic analyses and comparison with reported data. Together, all reported compounds were isolated from V. versicolor f. viride for the first time in the study. Among them, two flavone aglycone tricetins (7 and 9) have never been isolated from the genus Veratrum or the family Melanthiaceae. The ethanol extract …


Optimum Pyrolysis Conditions To Prepare The Most Crystalline Boron Carbide Powder From Boric Acid–Mannitol Complex Ester, ABDULLAH DEVRİM PEKDEMİR, MÜŞERREF ÖNAL, YÜKSEL SARIKAYA 2023 TÜBİTAK

Optimum Pyrolysis Conditions To Prepare The Most Crystalline Boron Carbide Powder From Boric Acid–Mannitol Complex Ester, Abdullah Devri̇m Pekdemi̇r, Müşerref Önal, Yüksel Sarikaya

Turkish Journal of Chemistry

A weak acidic complex ester (CE) in solid form was prepared by a condensation reaction between very weak boric acid (BA: H3BO3) and (D)-mannitol (MA: C6H14O6) by the molar ratio of BA/MA = 2. A boron carbide (B4C) precursor was obtained from heating of the CE at 400 °C for 4 h. The precursor was pyrolyzed under argon flow in the interval of 1300–1550 °C for 4 h and at 1400 °C for 1–4 h, respectively. The materials were examined using several techniques such as X-ray diffraction analysis, thermal analysis, scanning electron microscopy, particle size distribution, and nitrogen adsorption/desorption. The …


Poly(Vinyl Alcohol)/Zsm-5 Zeolite Mixed Matrix Membranes For Pervaporation Dehydration Of Ethanol And N-Propanol, JI TING WANG, ZHEN HUANG, YA TONG ZHU, SI NING WANG 2023 TÜBİTAK

Poly(Vinyl Alcohol)/Zsm-5 Zeolite Mixed Matrix Membranes For Pervaporation Dehydration Of Ethanol And N-Propanol, Ji Ting Wang, Zhen Huang, Ya Tong Zhu, Si Ning Wang

Turkish Journal of Chemistry

In this study, mixed matrix membranes (MMMs) composed of poly(vinyl alcohol) (PVA) and porous ZSM-5 zeolite are thoroughly investigated for concentrating alcohols of ethanol and n-propanol via dewatering pervaporation. The effects of the zeolite content (10–30 wt.%), feed composition (5–30 wt.% water), and feed temperature (50–90 °C) on the pervaporation flux/separation factor and component permeance/selectivity of these MMMs are examined in detail. These MMMs achieve higher separation efficiency and pervaporation flux than their pure PVA counterparts as expected, even if the dehydration results strongly depend on the pervaporation conditions. The disparity in pervaporation performances acquired for different alcohol solutions may …


Scope And Limitations Of The Preparation Of Xanthones Using Eaton’S Reagent, JOHANN BOSSON 2023 TÜBİTAK

Scope And Limitations Of The Preparation Of Xanthones Using Eaton’S Reagent, Johann Bosson

Turkish Journal of Chemistry

Xanthones comprise a large family of heterocycles displaying fascinating biological properties. Many synthetic protocols have been developed for the preparation of natural and nonnatural xanthone derivatives. Among them, condensation reactions between salicylic acid derivatives and phenol partners are highly desirable. Those reactions can be satisfactorily performed using Eaton’s reagent (P2O5 in CH3SO3H). Despite being highly effective with a variety of substrates, this approach presents limitations that depend on the electronic nature of the reaction precursors. The scope and limitations of the Eaton’s reagent-mediated preparation of xanthones are herein presented and discussed. In short, this approach is limited to the utilization …


Comparison Of Metal-Carbenoid Reactions Of Β-2-Five-Membered Heteroaryl Substituted Α,Β-Unsaturated Ketones, KUMSAL EROĞLU, OLCAY ANAÇ, FÜSUN ŞEYMA KIŞKAN 2023 TÜBİTAK

Comparison Of Metal-Carbenoid Reactions Of Β-2-Five-Membered Heteroaryl Substituted Α,Β-Unsaturated Ketones, Kumsal Eroğlu, Olcay Anaç, Füsun Şeyma Kişkan

Turkish Journal of Chemistry

In this study, β-2-heteroaryl substituted (N-methyl 2-pyrrolyl, 2-thiophenyl, 2-furyl) α,β-unsaturated ketones were reacted with two α-diazo carbonyl compounds that had different characteristics (dimethyl diazo malonate and 1-diazo-1-phenyl-propane-2-one) in the presence of both copper and rhodium catalysts. In the case of reactions with N-methyl 2-pyrrolyl α,β-unsaturated ketones, the major product was the insertion derivative. However, in the reactions of 2-thiophenyl and 2-furyl α,β-unsaturated ketones with dimethyl diazomalonate (acceptor-acceptor disubstituted), only dihydrofuran products were formed over carbonyl ylides. When 2-thiophenyl and 2-furyl α,β-unsaturated ketones were reacted with 1-diazo-1-phenyl-propane-2-one (donor-acceptor disubstituted), 1-phenylpropane-1,2-dione was obtained under our reaction conditions.


Synthesis And Singlet Oxygen Generation Of Boron- 2-(4,5-Dibromo-1h-Imidazole-2-Yl)-3,5-Dipyrazolopyridine Complex For Antimicrobial Photodynamic Therapy, ZEYNEP EKMEKÇİ, SEDA KARAOĞLU 2023 TÜBİTAK

Synthesis And Singlet Oxygen Generation Of Boron- 2-(4,5-Dibromo-1h-Imidazole-2-Yl)-3,5-Dipyrazolopyridine Complex For Antimicrobial Photodynamic Therapy, Zeynep Ekmekçi̇, Seda Karaoğlu

Turkish Journal of Chemistry

In this study, the pyridine side of a boron 2-(2'-pyridyl) imidazole (BOPIM) core, which has very few derivatives synthesized in the literature and can show fluorescence properties in solid form, was derivatized with 1-methylpyrazole, predicted to have activity against fungi or bacteria according to the literature. Additionally, its imidazole side was brominated to increase the efficiency of singlet oxygen production by increasing the intersystem crossing. The photophysical properties of the new synthesized BOPIM derivative were investigated in general organic solvents with different polarities. While the wavelength of the maximum absorbance was determined as 406 nm in CH2Cl2 and THF, the …


Removal Of Toxic Cr(Vi) From Aqueous Medium With Effective Magnetic Carbon-Based Nanocomposites, FERDA CİVAN ÇAVUŞOĞLU, GÜLSÜM ÖZÇELİK, ŞAHİKA SENA BAYAZİT 2023 TÜBİTAK

Removal Of Toxic Cr(Vi) From Aqueous Medium With Effective Magnetic Carbon-Based Nanocomposites, Ferda Ci̇van Çavuşoğlu, Gülsüm Özçeli̇k, Şahi̇ka Sena Bayazi̇t

Turkish Journal of Chemistry

Cr(VI), which has toxic effects, is a heavy metal and it must be removed from the environment due to the various damages it causes. In this study, the removal of Cr(VI) pollutants from aqueous solutions with Fe3O4-based materials using a batch adsorption technique was investigated. Magnetically modified graphene nanoplatelet (GNP)-based nanocomposites were prepared and their structures were characterized by FTIR, XRD, SEM, BET, and TGA techniques. The effects of various physicochemical parameters such as adsorbent dose, contact time, initial Cr(VI) solution concentration, pH, and the presence of coexisting ions (NaCl) on the adsorption process were investigated. Accordingly, the optimum conditions …


Intercalation Of Pyrazolone-Based Oxalamide Metal Complexes Into Na-Montmorillonite For Catalytic Liquid-Phase Oxidation Of Phenol Using H2o2, Serhat UZAN, EYÜP BAŞARAN 2023 TÜBİTAK

Intercalation Of Pyrazolone-Based Oxalamide Metal Complexes Into Na-Montmorillonite For Catalytic Liquid-Phase Oxidation Of Phenol Using H2o2, Serhat Uzan, Eyüp Başaran

Turkish Journal of Chemistry

The intercalation of pyrazolone-based oxalamide metal complexes into Na-montmorillonite (Na-MMT) for catalytic liquid-phase oxidation of phenol using H2O2 was undertaken by a flexible ligand method using metal ions including Mn(II), Zn(II), and Sn(II). First, the metal ions were exchanged with the sodium ions of Na-MMT, and then these metal ions were complexed with a new pyrazolone-based oxalamide ligand. The intercalated metal complexes were characterized by Fourier transform infrared spectroscopy, X-ray diffraction, scanning electron microscopy, energy-dispersive X-ray spectroscopy, elemental analysis, and thermogravimetric analysis. Phenol was successfully oxidized by heterogeneous catalysts based on Mn(II), Zn(II), and Sn(II) pyrazolone-based oxalamide complexes intercalated into …


Bromination And Conversion Of Tetrahydro-1h-Indene To Bisoxirane With A New Approach: Synthesis, Structural Characterization By Spectroscopic And Theoretical Methods, And Biological Analysis Supported By Dft And Docking, RAŞİT FİKRET YILMAZ, SULTAN ERKAN, SALİH ÖKTEN, AHMET TUTAR, ERTAN ŞAHİN 2023 TÜBİTAK

Bromination And Conversion Of Tetrahydro-1h-Indene To Bisoxirane With A New Approach: Synthesis, Structural Characterization By Spectroscopic And Theoretical Methods, And Biological Analysis Supported By Dft And Docking, Raşi̇t Fi̇kret Yilmaz, Sultan Erkan, Sali̇h Ökten, Ahmet Tutar, Ertan Şahi̇n

Turkish Journal of Chemistry

In this study, a new method for synthesizing diepoxides is proposed. Tetrahydroindene 1 was brominated with NBS in the presence of LiClO4 and acetic acid, resulting in the formation of dibromodiacetate derivatives 2 and 3. Treatment of compounds 2 and 3 with NaOH in methanol produced a mixture of diepoxides 4 and 5. Additionally, direct bromination of tetrahydro-1H-indene yielded tetrabromo octahydroindene isomers 6 and 7. The structures of the compounds were characterized using spectroscopic techniques such as 1H NMR, 13C NMR, APT, COSY, and XRD. The new method provides an easy and selective route to access epoxides for the synthesis …


Intelligent Control Based On Bp Artificial Neural Network For Electrochemical Nitrate Removal, Xin-Wan Zhang, Guang-Yuan Meng, Li-Qiang Fang, Ding-ming Chang, Tong Li, Jin-Wen Hu, Peng Chen, Yong-Di Liu, Le-Hua Zhang 2023 National Engineering Laboratory of High Concentration Refractory Organic Wastewater Treatment Technology, East China University of Science and Technology, Shanghai200237, China

Intelligent Control Based On Bp Artificial Neural Network For Electrochemical Nitrate Removal, Xin-Wan Zhang, Guang-Yuan Meng, Li-Qiang Fang, Ding-Ming Chang, Tong Li, Jin-Wen Hu, Peng Chen, Yong-Di Liu, Le-Hua Zhang

Journal of Electrochemistry

Achieving effective control of parameters in the process of nitrate wastewater treatment is critical to electrochemical water treatment. The powerful nonlinear mapping ability, self-adaptation and self-learning ability of neural network technology can optimize the electrochemical processing. However, there are few researches in this direction. Hence, based on the test data of the electrochemical reduction of nitrate, an electrochemical prediction model was established by using the BP neural network algorithm. Considering the correlation of various parameters in the electrochemical process, the reaction time, initial nitrate nitrogen concentration, pH and current density were determined as the input layer of the BP neural …


Nitrogen-Doped Graphite Felt On The Performance Of Aqueous Quinone-Based Redox Flow Batteries, Heng Zhang, Li-Xing Xia, Shan Jiang, Fu-Zhi Wang, Zhan-Ao Tan 2023 State Key Laboratory of Alternate Electrical Power System with Renewable Energy Sources, North China Electric Power University, Beijing 102206, China

Nitrogen-Doped Graphite Felt On The Performance Of Aqueous Quinone-Based Redox Flow Batteries, Heng Zhang, Li-Xing Xia, Shan Jiang, Fu-Zhi Wang, Zhan-Ao Tan

Journal of Electrochemistry

Modification of electrode is vitally important for achieving high energy efficiency in aqueous quinone-based redox flow batteries (AQRFBs). The modification of graphite felt (GF) was carried out by means of urea hydrothermal reaction, and simultaneously, the effects of hydrothermal reaction time on the functional groups and surface structure of nitrogen-doped graphite felt were studied. The surface morphology and defect, element content and surface chemical state of the modified electrode were characterized by scanning electron microscopy (SEM), Brunauer-Emmett-Teller (BET) test, Raman spectroscopy, and X-ray photoelectron spectroscopy (XPS). The electrochemical performance of the modified electrodes was evaluated by cyclic voltammetry, electrochemical impedance …


An In-Situ Raman Spectroscopic Study On The Interfacial Process Of Carbonate-Based Electrolyte On Nanostructured Silver Electrode, Yu Gu, Yuan-Fei Hu, Wei-Wei Wang, En-Ming You, Shuai Tang, Jian-Jia Su, Jun Yi, Jia-Wei Yan, Zhong-Qun Tian, Bing-Wei Mao 2023 State Key Laboratory of Physical Chemistry of Solid Surfaces, Innovation Laboratory for Sciences and Technologies of Energy Materials of Fujian Province (IKKEM), College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, Fujian, China

An In-Situ Raman Spectroscopic Study On The Interfacial Process Of Carbonate-Based Electrolyte On Nanostructured Silver Electrode, Yu Gu, Yuan-Fei Hu, Wei-Wei Wang, En-Ming You, Shuai Tang, Jian-Jia Su, Jun Yi, Jia-Wei Yan, Zhong-Qun Tian, Bing-Wei Mao

Journal of Electrochemistry

The solid-electrolyte interphase (SEI) plays a key role in anodes for rechargeable lithium-based battery technologies. However, a thorough understanding in the mechanisms of SEI formation and evolution remains a major challenge, hindering the rapid development and wide applications of Li-based batteries. Here, we devise a borrowing surface-enhanced Raman scattering (SERS) activity strategy by utilizing a size optimized Ag nanosubstrate to in-situ monitor the formation and evolution of SEI, as well as its structure and chemistry in an ethylene carbonate-based electrolyte. To ensure a reliable in-situ SERS investigation, we designed a strict air-tight Raman cell with a three-electrode configuration. Based on …


Electrochemical Performance Of Porous Ceramic Supported Tubular Solid Oxide Electrolysis Cell, Heng-Ji Wang, Wen-Guo Chen, Zhou-Yi Quan, Kai Zhao, Yi-Fei Sun, Min Chen, Ogenko Volodymyr 2023 School of Materials Science and Hydrogen Energy, Foshan University, Foshan 528000, China

Electrochemical Performance Of Porous Ceramic Supported Tubular Solid Oxide Electrolysis Cell, Heng-Ji Wang, Wen-Guo Chen, Zhou-Yi Quan, Kai Zhao, Yi-Fei Sun, Min Chen, Ogenko Volodymyr

Journal of Electrochemistry

Solid oxide electrolysis cell (SOEC) is an efficient and clean energy conversion technology that can utilize electricity obtained from renewable resources, such as solar, wind, and geothermal energy to electrolyze water and produce hydrogen. The conversion of abundant intermittent energy to hydrogen energy would facilitate the efficient utilization of energy resources. SOEC is an all-ceramic electrochemical cell that operates in the intermediate to high temperature range of 500–750 ℃. Compared with traditional low temperature electrolysis technology (e.g., alkaline or proton exchange membrane cells operating at ~100 ℃), the high-temperature SOEC can increase the electrolysis efficiency from 80% to ~100%, providing …


Combined Risk Based Inspection And Fault Tree Analysis For Repetitive 3-Phase Line Piping Leakage At West Java Offshore Topside Facility, Dona Yuliati, Akhmad Herman Yuwono, Datu Rizal Asral, Donanta Dhaneswara 2023 Universitas Indonesia

Combined Risk Based Inspection And Fault Tree Analysis For Repetitive 3-Phase Line Piping Leakage At West Java Offshore Topside Facility, Dona Yuliati, Akhmad Herman Yuwono, Datu Rizal Asral, Donanta Dhaneswara

Journal of Materials Exploration and Findings (JMEF)

Hydrocarbon releases might result in serious consequences in various aspects. In addition to the contribution to environmental pollution, repetitive leakages need high repair costs. This study aim is to minimize potential repetitive leakage for other typical 3-phase piping systems. We conducted the risk assessment by adopting Risk Based Inspection (RBI) API 581 to identify risk level, calculating piping lifetime, recommended inspection plan and mitigations. The most relevant root causes can be obtained through quantitative Fault Tree Analysis (FTA). Observation and investigation was taken from eight 3-phase piping systems that experienced repetitive leakages. It has been found that the risk level …


Nitrogen Gas Quenching Pressure Effect On Bs S155 Alloy Steel In Vacuum Furnace, Agus Mulyadi Hasanudin, Eddy Sumarno Siradj 2023 University of Indonesia, Depok

Nitrogen Gas Quenching Pressure Effect On Bs S155 Alloy Steel In Vacuum Furnace, Agus Mulyadi Hasanudin, Eddy Sumarno Siradj

Journal of Materials Exploration and Findings (JMEF)

The production of metal and alloy products requires the use of heat treatment, when during the heat treatment process, quenching is a crucial step. The quenching medium can be anything from water, a salt bath, oil, air and gas. In a vacuum furnace, pressurized gas, most frequently nitrogen (N2) gas, serves as one of the quenching mediums. One of the drawbacks of the quenching process is the distortion and dimensional change of the parts. This paper aims to investigate the influence of nitrogen gas quenching pressure on the distortion and dimensional change of aerospace actuator gear planet parts …


Search For Osme Bonds With Π Systems As Electron Donors, Xin Wang, Qingzhong Li, Steve Scheiner 2023 Yantai University

Search For Osme Bonds With Π Systems As Electron Donors, Xin Wang, Qingzhong Li, Steve Scheiner

Chemistry and Biochemistry Faculty Publications

The Osme bond is defined as pairing a Group 8 metal atom as an electron acceptor in a noncovalent interaction with a nucleophile. DFT calculations with the ωB97XD functional consider MO4 (M = Ru, Os) as the Lewis acid, paired with a series of π electron donors C2H2 , C2H4 , C6H6 , C4H5N, C4H4O, and C4H4S. The calculations establish interaction energies in the range between 9.5 and 26.4 kJ/mol. Os engages in stronger interactions than does Ru, …


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