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2021

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Articles 1471 - 1500 of 1742

Full-Text Articles in Chemistry

The Application Of 13c Nmr And Untargeted Multivariate Analysis For Classifying Virgin Coconut Oil, Lolita G. Lagurin, Mark Joseph Garrovillas, Fabian M. Dayrit Jan 2021

The Application Of 13c Nmr And Untargeted Multivariate Analysis For Classifying Virgin Coconut Oil, Lolita G. Lagurin, Mark Joseph Garrovillas, Fabian M. Dayrit

Chemistry Faculty Publications

Virgin coconut oil (VCO) is produced from fresh mature coconut meat without the use of chemicals or high heat. VCO can be made using three processes: fermentation, centrifuge, and expeller. To determine quality, it is important to be able to differentiate control VCO (fresh) from old VCO, refined bleached and deodorized coconut oil (RBDCO), and VCO which has been adulterated with RBDCO. Differentiating these types of samples has remained a challenge because of their chemical similarity. This study investigated the ability of 13C NMR and multivariate analysis to differentiate these different coconut oil samples. The methodology used the standard 13C …


Philippine Medicinal Plants With Potential Immunomodulatory And Anti-Sars-Cov-2 Activities, Fabian M. Dayrit, Armando M. Guidote Jr, Nina Gloriani, Sheriah Laine M. De Paz-Silava, Irene M. Villaseñor, Rene Angelo S. Macahig, Mario A. Tan, John Ross N. Chua, Isidro C. Sia Jan 2021

Philippine Medicinal Plants With Potential Immunomodulatory And Anti-Sars-Cov-2 Activities, Fabian M. Dayrit, Armando M. Guidote Jr, Nina Gloriani, Sheriah Laine M. De Paz-Silava, Irene M. Villaseñor, Rene Angelo S. Macahig, Mario A. Tan, John Ross N. Chua, Isidro C. Sia

Chemistry Faculty Publications

Coronavirus disease 2019 (COVID-19) continues to devastate the world’s health and economy, affecting all aspects of life leading to widespread social disruption. Even as several vaccines have been developed, their availability in developing countries is limited and their efficacy against the variants of SARS-CoV-2 (severe acute respiratory syndrome–coronavirus 2) needs to be continuously assessed. The World Health Organization (WHO) has acknowledged that vaccines alone will not overcome the global challenges of COVID-19. Medicinal plants may provide the needed support. Herein, we identify Philippine medicinal plants that possess phytochemicals with potential anti-SARS-CoV-2 activity and/or immunomodulatory properties that may strengthen one’s immune …


Influence Of Iceberg-Discharge Events On The Climate And Circulation Of The Central North Atlantic Ocean During The Last Glaciation, Ava Mcilvaine Jan 2021

Influence Of Iceberg-Discharge Events On The Climate And Circulation Of The Central North Atlantic Ocean During The Last Glaciation, Ava Mcilvaine

Scripps Senior Theses

The repeated occurrence of episodic iceberg-discharge events and abrupt climate change in the North Atlantic Ocean is well-documented for the late Quaternary period. However, much of the evidence for these periods known as Heinrich Events comes from the subpolar region, where deposition can be dominated by ice-rafted debris (IRD) and overwhelm other oceanographic and climatic indicators. Thus, the following analysis of coarse sediment from Integrated Ocean Drilling Program (IODP) Core Site U1313 (41°0.0'N, 32°57.42'W) evaluated ocean cooling related to ice-rafting, water mass migration, and climate change over the approximate last 100,000 years. Site U1313 is located near the North Atlantic …


“The Production Of Eight Plasmid Expression Vectors Through Gibson Assembly And The Optimization Of The Enzymatic Cleavage Reaction Between Tobacco Etch Virus (Tev) And The Model Fusion Protein, Nus-G”, Elizabeth Kennard Jan 2021

“The Production Of Eight Plasmid Expression Vectors Through Gibson Assembly And The Optimization Of The Enzymatic Cleavage Reaction Between Tobacco Etch Virus (Tev) And The Model Fusion Protein, Nus-G”, Elizabeth Kennard

Student Summer Scholars Manuscripts

Snake envenomization is a neglected public health issue that effects large portions of the world, as venomous snakes are found on six continents (World Health Organization,2007). With 2-3 million people bitten globally every year leading to an estimated 125,000 deaths and 400,000 amputations, researching effective treatments is important. Several Mammalian species have a natural resistance to snake venom (Voss, R.S et al.,2012; Bastos, V.A. et al.,2016). The North American Opossum (D. virginiana) produces proteins that inhibit certain snake venom components including snake venom metalloproteinases (SVMPs) and phospholipase 2As (PLA2s) (Catanese, J.J. et al.,1992; Perales, J. et al.,1994; Farah, M.D.F.L. et …


Dicer Represses The Interferon Response And The Double-Stranded Rna-Activated Protein Kinase Pathway In Mouse Embryonic Stem Cells, Chandan Gurung, Mona Fendereski, Krishna Sapkota, Jason Guo, Faqing Huang, Yan Lin Guo Jan 2021

Dicer Represses The Interferon Response And The Double-Stranded Rna-Activated Protein Kinase Pathway In Mouse Embryonic Stem Cells, Chandan Gurung, Mona Fendereski, Krishna Sapkota, Jason Guo, Faqing Huang, Yan Lin Guo

Faculty Publications

Recent studies have demonstrated that embryonic stem cells (ESCs) are deficient in expressing type I interferons (IFN), the cytokines that play key roles in antiviral responses. However, the underlying molecular mechanisms and biological implications of this finding are poorly understood. In this study, we developed a synthetic RNA-based assay that can simultaneously assess multiple forms of antiviral responses. Dicer is an enzyme essential for RNA interference (RNAi), which is used as a major antiviral mechanism in invertebrates. RNAi activity is detected in wild-type ESCs but is abolished in Dicer knockout ESCs (D-/-ESCs) as expected. Surprisingly, D-/-ESCs have gained the ability …


Direct Determination Of Absolute Stereochemistry Of Α-Methylselenocysteine Using The Mosher Method, Robert J. Wehrle, Douglas R. Powell, Douglas S. Masterson Jan 2021

Direct Determination Of Absolute Stereochemistry Of Α-Methylselenocysteine Using The Mosher Method, Robert J. Wehrle, Douglas R. Powell, Douglas S. Masterson

Faculty Publications

Mosher amides of α-methylselenocysteine were synthesized to determine the absolute stereochemistry of the sterically hindered α-carbon utilizing 1H, 13C, 19F, and 77Se NMR spectroscopies. After analysis of these spectra using the established Mosher method, the stereochemistry of the α-carbon was determined to be (R), which was subsequently confirmed using x-ray crystallography.


One-Pot Synthesis Of 2-Methylfurans From 3- (Trimethylsilyl)Propargyl Acetates Promoted By Trimethylsilyl Trifluoromethanesulfonate, Danielle E. Sklar, Alex V. Helbling, Yiqi Liu, C. Wade Downey Jan 2021

One-Pot Synthesis Of 2-Methylfurans From 3- (Trimethylsilyl)Propargyl Acetates Promoted By Trimethylsilyl Trifluoromethanesulfonate, Danielle E. Sklar, Alex V. Helbling, Yiqi Liu, C. Wade Downey

Chemistry Faculty Publications

In the presence of trimethylsilyl trifluoromethanesulfonate (TMSOTf) and triethylamine, 3-(trimethylsilyl)propargyl carboxylates undergo a one-pot alkylation-cyclization- desilylation reaction with ketones to produce 2-methylfurans. Alkylation at 0 °C in methylene chloride, followed by acid-catalyzed cyclization at room temperature, provides the furans in 52-86% yield. Cyclization and desilylation appear to be promoted by triflic acid generated in situ from the exposure of the reaction mixture to water upon completion of the initial substitution reaction.


Friedel–Crafts Addition Of Indoles To Nitrones Promoted By Trimethylsilyl Trifluoromethanesulfonate, Zachary Z. Oracheff, Helen L. Xia, Christopher D. Poff, Scott E. Isaacson, C. Wade Downey Jan 2021

Friedel–Crafts Addition Of Indoles To Nitrones Promoted By Trimethylsilyl Trifluoromethanesulfonate, Zachary Z. Oracheff, Helen L. Xia, Christopher D. Poff, Scott E. Isaacson, C. Wade Downey

Chemistry Faculty Publications

N-alkylindoles undergo Friedel–Crafts addition to aryl and secondary alkyl nitrones in the presence of trimethylsilyl trifluoromethanesulfonate and a trialkylamine to produce 3-(1- (silyloxyamino)alkyl)indoles. Spontaneous conversion to the bisindolyl(aryl)methanes, which is thermodynamically favored for nitrones derived from aromatic aldehydes, is suppressed under the reaction conditions. The silyloxyamino group can be deprotected with tetrabutylammonium fluoride to yield the hydroxylamine.


Biocompatible And Multifunctional Trityl Spin Probes For Electron Paramagnetic Resonance Spectroscopy, Teresa D. Gluth Jan 2021

Biocompatible And Multifunctional Trityl Spin Probes For Electron Paramagnetic Resonance Spectroscopy, Teresa D. Gluth

Graduate Theses, Dissertations, and Problem Reports (ETD)

The primary objective of my thesis was to develop and utilize a biocompatible multifunctional trityl spin probe for concurrent measurement of pO2, pHe, and [Pi] in vivo by electron paramagnetic resonance (EPR) spectroscopy (Chapter 2). My first goal was to synthesize the proposed probe we are terming HOPE71. Secondly, HOPE71 was characterized by X-band and L-band EPR spectroscopy. Next, the biocompatibility of HOPE71 was assessed through an albumin binding test, cytotoxicity assays, and in vivo intravenous tolerance. Then, the use of HOPE71 to measure the target parameters was demonstrated in a breast cancer …


Efficiency Enhancement With Chloride To Iodide Ion Exchange Of Benzimidazolium Salt Asa Redox Mediator, Serkan Dayan, Mert Olgun Karataş, Bülent Alici, Ni̇lgün Kalaycioğlu Özpozan Jan 2021

Efficiency Enhancement With Chloride To Iodide Ion Exchange Of Benzimidazolium Salt Asa Redox Mediator, Serkan Dayan, Mert Olgun Karataş, Bülent Alici, Ni̇lgün Kalaycioğlu Özpozan

Turkish Journal of Chemistry

The new benzimidazolium derivative (SM-1) salt with ion exchange from the (SM-0) was fabricated and characterized by protonnuclear magnetic resonance (1H-NMR), carbon-nuclear magnetic resonance (13C-NMR), Fourier-transform infrared spectroscopy (FTIR), electrospray ionization (EIS-MS), thermal analysis (TG), cyclic voltammetry (CV), and ultraviolet-visible spectroscopy (UV-vis), for electrolytes (liquid or dried) in the DSSC charge transportation mechanism. Also, the influence of ion exchange from chloride to iodine in the synthesized electrolytes, compared to other electrolytes (conventional or commercial), was investigated about DSSC performance efficiency. When using as a liquid electrolyte (SM-1), the power conversion efficiency (η) of the working DSSC device was recorded as …


Reusability And Regeneration Of Solid Catalysts Used In Ultrasound Assisted Biodieselproduction, Mahmut Rahi̇m Bayramoğlu, İbrahi̇m Korkut, Başak Temur Ergan Jan 2021

Reusability And Regeneration Of Solid Catalysts Used In Ultrasound Assisted Biodieselproduction, Mahmut Rahi̇m Bayramoğlu, İbrahi̇m Korkut, Başak Temur Ergan

Turkish Journal of Chemistry

Reusability of two heterogeneous catalysts in ultrasound (US) assisted biodiesel production was investigated in comparison to each other. An ultrasound (US) generator (200 W, 20 kHz) equipped with a horn type probe (19 mm) was used. Regeneration experiments were planned according to second order central composite design (CCD) method. After the eighth use of the catalysts, biodiesel yield decreased from 99.1% to 90.4% for calcined calcite (CaO) and from 98.8% to 89.8% for calcined dolomite (CaO.MgO). Furthermore, regeneration of spent catalysts by calcination was investigated; optimum temperature and time were found as 750 °C and 90 min, lower than fresh …


Tin-Sulfur Based Catalysts For Acetylene Hydrochlorination, Yibo Wu, Fuxiang Li, Xiaoqiang Luo, Gang Tian, Yunxiao Feng, Yongjun Han, Li Wang, Songmao Chu, Yunli Cao, Kesheng Cao, Xiaoming Hu, Xuejun Shi, Songtian Li, Guoxv He, Qingbin Li Jan 2021

Tin-Sulfur Based Catalysts For Acetylene Hydrochlorination, Yibo Wu, Fuxiang Li, Xiaoqiang Luo, Gang Tian, Yunxiao Feng, Yongjun Han, Li Wang, Songmao Chu, Yunli Cao, Kesheng Cao, Xiaoming Hu, Xuejun Shi, Songtian Li, Guoxv He, Qingbin Li

Turkish Journal of Chemistry

In the present work, tin-sulfur based catalysts were prepared using Na2SO3 and (CH3SO3)2Sn and were tested in acetylene hydrochlorination. Based on the analysis of experiments results, the acetylene conversion of (CH3SO3)2Sn/S@AC is still over 90% after a 50 h reaction, at the reaction conditions of T = 200 oC, VHCl/VC2H2 = 1.1:1.0 and C2H2-GSHV = 15 h-1. According to the results of X-ray photoelectron spectroscopy (XPS), HCl adsorption experiments, and acetylene temperature programmed desorption (C2H2-TPD), it is reasonable to conclude that the interaction between Sn and S not only can retard the oxidation of Sn2+ in catalysts but also strengthen …


Investigation Of Performances Of Commercial Diesel Oxidation Catalysts For Co, C3h6, And No Oxidation, Hande Güneş, Deni̇z Şanli Yildiz, Hüseyi̇n Barkin Özener, Gökhan Hi̇sar, Selmi̇ Eri̇m Bozbağ, Can Erkey Jan 2021

Investigation Of Performances Of Commercial Diesel Oxidation Catalysts For Co, C3h6, And No Oxidation, Hande Güneş, Deni̇z Şanli Yildiz, Hüseyi̇n Barkin Özener, Gökhan Hi̇sar, Selmi̇ Eri̇m Bozbağ, Can Erkey

Turkish Journal of Chemistry

Four commercial monolithic diesel oxidation catalysts (DOCs) with two different platinum group metal (PGM) loadings and Pt:Pd ratios of 1:0, 2:1, 3:1 (w/w) were investigated systematically for CO, C3H6, and NO oxidation, CO-C3H6 co-oxidation, and CO-C3H6-NO oxidation reactions via transient activity measurements in a simulated diesel engine exhaust environment. As PGM loading increased, light-off curves shifted to lower temperatures for individual and co-oxidation reactions of CO and C3H6. CO and C3H6 were observed to inhibit the oxidation of themselves and each other. Addition of Pd to Pt was found to enhance CO and C3H6 oxidation performance of the catalysts while …


Synthesis And Molecular Docking Study Of Novel Covid-19 Inhibitors, Zuhal Gerçek, Deni̇z Ceyhan, Erol Erçağ Jan 2021

Synthesis And Molecular Docking Study Of Novel Covid-19 Inhibitors, Zuhal Gerçek, Deni̇z Ceyhan, Erol Erçağ

Turkish Journal of Chemistry

In 2020, the world tried to combat the corona virus (COVID-19) pandemic. A proven treatment method specific to Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2) is still not found. In this study, seven new antiviral compounds were designed for COVID-19 treatment. The ability of these compounds to inhibit COVID-19's RNA processing was calculated by the molecular docking study. It has been observed that the compounds can have high binding affinities especially against NSP12 (between -9.06 and -8.00 kcal/mol). The molecular dynamics simulation of NSP12-ZG 7 complex proved the stability of interaction. The synthesis of two most active molecules was performed by …


Thermal Stresses In Sofc Stacks: The Role Of Mismatch Among Thermalconductivity Of Adjacent Components, Özgür Aydin, Go Matsumoto, Yusuke Shiratori Jan 2021

Thermal Stresses In Sofc Stacks: The Role Of Mismatch Among Thermalconductivity Of Adjacent Components, Özgür Aydin, Go Matsumoto, Yusuke Shiratori

Turkish Journal of Chemistry

Generating power from renewable biogas in solid oxide fuel cells (SOFCs) is an environment-friendly, efficient, and promising energy conversion process. Biogas can be used in SOFCs via a reforming process for which dry reforming is more suitable as the reforming agent exists in the biogas mixture. Biogas can be directly reformed to H2 -rich fuel stream in the anode chamber of a SOFC by the heat released during power generation. Exploiting the heat and water produced in the SOFC for internal reforming of biogas makes the energy conversion process very efficient; however, various challenges are reported. Thus, indirect internal reforming …


Synthesis Of Hydroxy Benzoin/Benzil Analogs And Investigation Of Their Antioxidant,Antimicrobial, Enzyme Inhibition, And Cytotoxic Activities, Nuretti̇n Yayli, Gözde Kiliç, Gonca Çeli̇k, Nuran Kahri̇man, Şeyda Kanbolat, Ari̇f Bozdeveci̇, Şengül Alpay Karaoğlu, Rezzan Ali̇yazicioğlu, Hasan Erdi̇nç Selli̇tepe, İnci̇ Seli̇n Doğan, Ali̇ Aydin Jan 2021

Synthesis Of Hydroxy Benzoin/Benzil Analogs And Investigation Of Their Antioxidant,Antimicrobial, Enzyme Inhibition, And Cytotoxic Activities, Nuretti̇n Yayli, Gözde Kiliç, Gonca Çeli̇k, Nuran Kahri̇man, Şeyda Kanbolat, Ari̇f Bozdeveci̇, Şengül Alpay Karaoğlu, Rezzan Ali̇yazicioğlu, Hasan Erdi̇nç Selli̇tepe, İnci̇ Seli̇n Doğan, Ali̇ Aydin

Turkish Journal of Chemistry

In this study, hydroxy benzoin (1-7), benzil (8-14), and benzoin/benzil-O-β-D-glucosides (15-25) were synthesized to investigate their biological activities. An efficient method for synthesizing hydroxy benzoin compounds (1-7) was prepared from four different benzaldehydes using an ultrasonic bath. Then, antioxidant (FRAP, CUPRAC, and DPPH), antimicrobial (3 Gram (-), 4/6 Gram (+), one tuberculosis and one fungus), and enzyme inhibition (acetylcholinesterase, butyrylcholine esterase, tyrosinase, α-amylase, and α- glucosidase) for the all synthesized compounds (1-25) were evaluated. And also, four most active compounds (4, 12, 18a+b, and 25) from each group were evaluated to the human cervical cancer cell line (HeLa) and anticancer …


Synthesis And Antioxidant Activities Of New Nickel(Ii) Complexes Derived From 4-Benzy¬Loxysalicylidene-S-Methyl/Propyl Thiosemicarbazones, Songül Eğlence Bakir Jan 2021

Synthesis And Antioxidant Activities Of New Nickel(Ii) Complexes Derived From 4-Benzy¬Loxysalicylidene-S-Methyl/Propyl Thiosemicarbazones, Songül Eğlence Bakir

Turkish Journal of Chemistry

Six nickel(II) complexes of the N2O2 chelating thiosemicarbazones were synthesized using N1-4-benzyloxysalicylidene-S-methyl/propyl thiosemicarbazone and methoxy-substitute-salicylaldehydes in the presence of Ni(II) ion by template reaction. The structures of thiosemicarbazones and nickel(II) complexes were characterized by elemental analysis, UV-Vis, IR, and 1H-NMR spec¬troscopies. The structure of the N1-4-benzyloxysalicylidene-S-propyl thiosemicarbazone (2) was determined by X-ray single-crystal diffraction method. The total antioxidant capacities of synthesized compounds were evaluated by using cupric reducing antioxidant capacity (CUPRAC) method. The thiosemicarbazones exhibited more potent antioxidant capacity than Ni(II) complexes. Trolox equiv¬alent antioxidant capacity (TEAC) of 1c was found highest in tested nickel(II) complexes. In addition, antioxidant activities …


Synthesis, Spectroscopic, Thermal, Crystal Structure Properties, And Characterization Of New Hofmann-Td-Type Complexes With 3-Aminopyridine, Zeki̇ Kartal, Onur Şahi̇n Jan 2021

Synthesis, Spectroscopic, Thermal, Crystal Structure Properties, And Characterization Of New Hofmann-Td-Type Complexes With 3-Aminopyridine, Zeki̇ Kartal, Onur Şahi̇n

Turkish Journal of Chemistry

In this study, synthesis of two new tetracyanocadmate(II) and tetracyanozincate(II) complexes based on 3-aminopyridine (3AP) and investigation of their structural properties were reported. These complexes were characterized by using vibration spectroscopy, elemental, thermal analysis and single crystal X-ray diffraction (SC-XRD) techniques. Investigation of the elemental, spectral and single crystal data of these complexes showed that the formulas [Cd(3AP)2Zn(μ4-CN)4]n (1) and [Cd(3AP) 2Cd(μ4-CN)4]n (2) fully explained their crystal structure. General information about the structural and chemical properties of these complexes obtained in single crystal form was obtained by observing the changes in the characteristic peaks of the 3AP with the [Zn(μ4-CN)4]2- …


Novel Mixed Ligand Coordination Compounds Of Some Rare Earth Metal Cations Containing Acesulfamato/N,N-Diethylnicotinamide, Leri̇man Zeybel, Dursun Ali̇ Köse Jan 2021

Novel Mixed Ligand Coordination Compounds Of Some Rare Earth Metal Cations Containing Acesulfamato/N,N-Diethylnicotinamide, Leri̇man Zeybel, Dursun Ali̇ Köse

Turkish Journal of Chemistry

The mixed ligand coordination compounds containing acesulfamato and N,N-diethylnicotinamide biomolecules of some rare earth metal cations (Eu3+, Tb3+, Ho3+, Er3+ and Yb3+) were synthesized, and their structural properties were investigated. Possible structural formulas have been proposed by determining the chemical composition of molecules (elemental analysis), binding properties (infrared spectroscopy, mass analysis, solid-state UV-vis spectroscopy), thermal degradation properties (TGA / DTA curves). Based on the data collected, it is suggested that rare earth metal cations with a 3+ oxidation state have sextet coordination. The geometries of the structures were thought to be distorted octahedral. The charge balance of the coordination sphere …


Binding Of Permanganate Anion To Pentaammineazidocobalt(Iii) Cation In Solution And Solid Phases: Synthesis, Characterization, X-Ray Structure, And Genotoxic Effects Of [Co(Nh3)5n3](Mno4)2•H2o, Ritu Bala, Jinkwon Kim, Vinit Prakash Jan 2021

Binding Of Permanganate Anion To Pentaammineazidocobalt(Iii) Cation In Solution And Solid Phases: Synthesis, Characterization, X-Ray Structure, And Genotoxic Effects Of [Co(Nh3)5n3](Mno4)2•H2o, Ritu Bala, Jinkwon Kim, Vinit Prakash

Turkish Journal of Chemistry

A pentaammineazidocobalt(III) complex, [Co(NH3)5N3](MnO4)2XH2O has been synthesized by an one-pot synthesis method. It was characterized by studies such as infrared (IR) and UV-visible spectroscopy. The single crystal X-ray structure analysis revealed that the title complex crystallizes in space group Cc. The cobalt center is six coordinated with slightly octahedral geometry. The supramolecular architecture is also formed by intermolecular N-H…O (anion and H2O) and Mn-O…O-H hydrogen bonds. The binding property of the cation, [Co(NH3)5N3]2+ with the anion, MnO4- has also been determined (in solution phase) with the help of UV-visible spectroscopic titrations. Further, the genotoxic effects of KMnO4, [Co(NH3)5N3]Cl2 and [Co(NH3)5N3](MnO4)2XH2O …


Evaluation Of Quercetin As A Potential Β-Lactamase Ctx-M-15 Inhibitor Via The Molecular Docking, Dynamics Simulations, And Mmgbsa, Emrah Sariyer, Ayşegül Saral Jan 2021

Evaluation Of Quercetin As A Potential Β-Lactamase Ctx-M-15 Inhibitor Via The Molecular Docking, Dynamics Simulations, And Mmgbsa, Emrah Sariyer, Ayşegül Saral

Turkish Journal of Chemistry

Antimicrobial resistance (AMR) threatens millions of people around the world and has been declared a global risk by the World Economic Forum. One of the important AMR mechanisms in Enterobacteriaceae is the production of extended-spectrum β-lactamases. The most common ESBL, CTX-M β-lactamases, is spread to the world by CTX-M-15 and CTX-M-14. Sulbactam, clavu-lanic acid, and tazobactam are first-generation β-lactamase inhibitors and avibactam is a new non-β-lactam β-lactamase inhibitor. We studied that avibactam, sulbactam, clavulanic acid, tazobactam, and quercetin natural flavonoids were docked to target protein CTX-M-15. Subsequently, the complexes were simulated using the molecular dynamics simulations method during 100 ns …


Impact Of Graphitic Carbon Nitrides Synthesized From Different Precursors On Schottky Junction Characteristics, Orhan Altan Jan 2021

Impact Of Graphitic Carbon Nitrides Synthesized From Different Precursors On Schottky Junction Characteristics, Orhan Altan

Turkish Journal of Chemistry

Graphitic carbon nitride (g-CN) has gained wide interest in many areas, such as energy and the environmental remediation as a layered polymeric semiconductor that allows the formation of catalytically active Schottky junctions due to its proper electronic band structure. Interestingly, although it is known that the precursors used in the synthesis, can influence the properties of the g-CN, no detailed study on these effects on Schottky junctions could be found in the literature. In this research, the effects of g-CNs synthesized by thermal polycondensation of different precursors on the photocatalytic efficiency of Schottky junctions were investigated. For this purpose, urea, …


Fabrication And Characterization Of Enhanced Hydrazine Electrochemical Sensor Based On Gold Nanoparticles Decorated On The Vanadium Oxide, Ruthenium Oxide Nanomaterials, And Carbon Nanotubes Composites, Si̇bel Karaca, Süleyman Koçak Jan 2021

Fabrication And Characterization Of Enhanced Hydrazine Electrochemical Sensor Based On Gold Nanoparticles Decorated On The Vanadium Oxide, Ruthenium Oxide Nanomaterials, And Carbon Nanotubes Composites, Si̇bel Karaca, Süleyman Koçak

Turkish Journal of Chemistry

This work describes the synthesis of mixed oxide film of vanadium and ruthenium by pulsed deposition technique on multiwall carbon nanotubes and the decoration of gold nanoparticles on the mixed film. A ternary electrocatalyst has been developed for the electrochemical oxidation of hydrazine by combining two metal oxide mixtures with Au nanoparticles. Surface morphology and chemical composition of the electrode have been examined with SEM, EDX, HRTEM, EIS, and XRD. The peak current of hydrazine increased 9 times at the AuNPs/(VOx-RuOx)/CNT/GCE compared to the bare GCE, and the peak potential shifted to negative 848 mV. Linear sweep voltammetry (LSV) and …


Structural And Adsorption Behaviour Of Zno/Aminated Swcnt-Cooh For Malachite Green Removal: Face-Centred Central Composite Design, Zeynep Ci̇ğeroğlu Jan 2021

Structural And Adsorption Behaviour Of Zno/Aminated Swcnt-Cooh For Malachite Green Removal: Face-Centred Central Composite Design, Zeynep Ci̇ğeroğlu

Turkish Journal of Chemistry

In this study, an effective adsorbent was synthesized to remove malachite green (MG), which is one of the toxic dyes. Firstly, single walled carbon nanotube with carboxylated acid (SWCNT-COOH) was functionalized with diethylenetriamine and a new nanocomposite was obtained using nano zinc oxide (ZnO) powder. The effects of pH (3-7), the amount of adsorbent (5-15 mg) and the initial concentration (10-50 mg L-1) of the solution on the adsorption uptake were investigated. The optimal parameters that maximize the adsorption uptake according to the specified working range are found to be 4.63 for pH, 49.94 mg L-1 for initial concentration, 5.25 …


Preparation And Characterization Of Templated Porous Carbons From Sucrose By One-Pot Method And Application As A Co2 Adsorbent, Meltem Gürbüz, Fatma Tümsek Jan 2021

Preparation And Characterization Of Templated Porous Carbons From Sucrose By One-Pot Method And Application As A Co2 Adsorbent, Meltem Gürbüz, Fatma Tümsek

Turkish Journal of Chemistry

The templated porous carbons were prepared from sucrose by one-pot method. In this method in which the pre-synthesis of the hard template is eliminated, the porous carbons were produced by organic-inorganic self-assembly of sucrose, tetraethyl ortosilicate (TEOS), Pluronic P123 and n-butanol in an acidic medium, and subsequent carbonization. The synthesis parameters such as sucrose amount, TEOS molar ratio and carbonization temperature were evaluated for describing their effects on the pore structures of the synthesized carbons. The prepared porous carbons were characterized by N2 adsorption, thermogravimetric analysis (TGA), Raman spectroscopy, X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), and transmission …


Catalytic, Theoretical, And Biological Investigation Of An Enzyme Mimic Model, Gülci̇han Gülseren Jan 2021

Catalytic, Theoretical, And Biological Investigation Of An Enzyme Mimic Model, Gülci̇han Gülseren

Turkish Journal of Chemistry

Artificial catalyst studies were always stayed at the kinetics investigation level, in this work bioactivity of designed catalyst were shown by the induction of biomineralization of the cells, indicating the possible use of enzyme mimics for biological applications. The development of artificial enzymes is a continuous quest for the development of tailored catalysts with improved activity and stability. Understanding the catalytic mechanism is a replaceable step for catalytic studies and artificial enzyme mimics provide an alternative way for catalysis and a better understanding of catalytic pathways at the same time. Here we designed an artificial catalyst model by decorating peptide …


Low Loaded Pt-Co Catalyst Surfaces Optimized By Magnetron Sputtering Sequentialdeposition Technique For Pem Fuel Cell Applications: Physical And Electrochemicalanalysis On Carbon Paper Support, Osman Öztürk, Aydin Haşi̇moğlu, Oğuz Kaan Özdemi̇r, İnci̇ Karaaslan, Ali̇ Şems Ahsen Jan 2021

Low Loaded Pt-Co Catalyst Surfaces Optimized By Magnetron Sputtering Sequentialdeposition Technique For Pem Fuel Cell Applications: Physical And Electrochemicalanalysis On Carbon Paper Support, Osman Öztürk, Aydin Haşi̇moğlu, Oğuz Kaan Özdemi̇r, İnci̇ Karaaslan, Ali̇ Şems Ahsen

Turkish Journal of Chemistry

A series of thin Pt-Co films with different metal ratios were deposited by using the sequential cosputtering directly on a commercial hydrophobic carbon paper substrate at room temperature and in ultra-high vacuum (UHV) conditions. Their electrocatalytic properties toward the oxygen reduction reaction were investigated in 0.5 M H2SO4 solution by means of cyclic voltammetry (CV) and linear sweep voltammetry (LSV) on rotating disc electrode (RDE). The results showed that Pt particles, deposited by dc-magnetron gun, surround the large Co-clusters deposited by rf-magnetron gun. In addition, the increase of Co content led to an increase in the electrochemical active surface area …


N Doping Of Tio2 Nanocrystal For Efficient Photodegradation Of Organic Pollutants Underultraviolet And Visible Light Irradiation, Xiaoyou Yu, Qianrui Lv Jan 2021

N Doping Of Tio2 Nanocrystal For Efficient Photodegradation Of Organic Pollutants Underultraviolet And Visible Light Irradiation, Xiaoyou Yu, Qianrui Lv

Turkish Journal of Chemistry

To decrease the band gap of TiO2 and enhance its photocatalytic performance, in this work, N-doped nanocrystalline TiO2 is synthesized successfully through a simple sol-gel synthesis process with dicyandiamide used as N source. The N-doped TiO2 photocatalysts have been characterized in detail by means of powder X-ray diffraction, Raman spectroscopy, infrared spectroscopy, UV-vis spectroscopy, X-ray photoelectron spectroscopy, and scanning electron microscope. The photocatalytic activities of N-doped TiO2 to different organic pollutants are significantly different. Using 2 × 10-5 mol/L methylene blue as the target pollutant, N-doped TiO2 can produced approximately 100% conversion within 40 min, the photocatalytic degradation ability of …


Effect Of Fuel Choice On Conductivity And Morphological Properties Of Samarium Doped Ceria Electrolytes For It-Sofc, Burcu Aygün, Vedat Sariboğa, Mehmet Ali̇ Faruk Öksüzömer Jan 2021

Effect Of Fuel Choice On Conductivity And Morphological Properties Of Samarium Doped Ceria Electrolytes For It-Sofc, Burcu Aygün, Vedat Sariboğa, Mehmet Ali̇ Faruk Öksüzömer

Turkish Journal of Chemistry

The present investigation is emphasized on the effect of various combustion agents on the crystal properties, surface microstructure, and oxygen ion conductivity of 20% mole-Sm doped ceria (Ce0.80Sm0.20O1.90/SDC20) ceramics as solid electrolyte for ITSOFCs. The most widely used combustion agents for engineering ceramic production as ethylene glycol, diethylene glycol, triethylene glycol, L-alanine, L-valine, glycine, citric acid monohydrate, urea, and EDTA-citric acid were compared in terms of SDC20 properties. X-ray diffraction (XRD), scanning electron microscopy (SEM), thermogravimetric analysis (TGA), and electrochemical impedance spectroscopy (EIS) were used to determine the microstructure properties, crystal structure and ionic conductivity of SDC20 powder. XRD pattern …


Photocatalytic Decomposition Of Textile Dyestuffs By Photosensitive Metal Oxide Catalysts, Esra Yeli̇z Altun, Zehra Tuba Şi̇şmanoğlu, Güli̇n Selda Pozan Soylu Jan 2021

Photocatalytic Decomposition Of Textile Dyestuffs By Photosensitive Metal Oxide Catalysts, Esra Yeli̇z Altun, Zehra Tuba Şi̇şmanoğlu, Güli̇n Selda Pozan Soylu

Turkish Journal of Chemistry

Textile azo dyes are one of the pollutants in waste water that adversely affect human and environmental health. Removal of these chemicals from wastewater is important for eco-system and human health. In this study, Bi2O3 nanoflakes and ZnO were synthesized by the co-precipitation method. Adsorption and photocatalytic degradation reactions were carried out to remove dyes (Victoria blue (VB) and Malachite green (MG)) from wastewater with the photocatalysts. In order to improve the activity of catalysts, cetyltrimethylammoniumbromide (CTAB) was added as a surfactant to pure oxide structures, and Bi2O3-CTAB and ZnO-CTAB catalysts were prepared. The structural and morphological properties of these …