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Full-Text Articles in Physical Sciences and Mathematics
Synthesis Of Metallo-Supramolecular Materials Based On Terpyridine Functionalized Double-Decker Silsesquioxane With Improved Complexation Efficienc, Asuman Çeli̇k Küçük, Jun Matsui, Tokuji Miyashita
Synthesis Of Metallo-Supramolecular Materials Based On Terpyridine Functionalized Double-Decker Silsesquioxane With Improved Complexation Efficienc, Asuman Çeli̇k Küçük, Jun Matsui, Tokuji Miyashita
Turkish Journal of Chemistry
Silsesquioxane-based transition-metal complexes have come to the forefront due to the ability of silsesquioxane to control nanostructures and properties. However, some difficulties in complete complexation and purification limit the widespread use of transition-metal-based supramolecular coordination complexes comprising silsesquioxane. Herein, 2 different approaches have been proposed for the synthesis of metallo-supramolecular materials on the basis of ruthenium(II)-terpyridine functional double-layer silsesquioxane (DDSQ) (Tpy/Ru-DDSQ) (Routes 1 and 2). In Route 1, complexation was followed by functionalization of DDSQ with the ligand, whereas in Route 2, complexation was performed before the ligand was inserted into the DDSQ. Tpy/Ru-DDSQ obtained from both approaches was characterized …
Bioreduction: The Biological Activity, Characterization, And Synthesis Of Silver Nanoparticles, Nesri̇n Korkmaz
Bioreduction: The Biological Activity, Characterization, And Synthesis Of Silver Nanoparticles, Nesri̇n Korkmaz
Turkish Journal of Chemistry
Today, nanoparticles are effectively used in different areas. Initially, physical and chemical methods were used in the synthesis of nanoparticles. Biosynthesis (green synthesis) has emerged as an alternative to overcome the toxic effects of chemically synthesized nanoparticles. In this study, green synthesis of silver nanoparticles (AgNPs) with the leaf extract of Anthurium andraeanum was performed. UV-Vis spectrophotometry, scanning transmission electron microscopy, and XRD were applied to characterize the biosynthesized nanoparticles. As a result of the characterization, the spectra showed that a spectrum at a wavelength of about 419 nm and a spherical size of 38 nm nanoparticles was formed. Antibacterial …
Multiwall Carbon Nanotube-Supported Molybdenum Catalysts For Ammonia Decomposition Reaction Under Microwave Effect, Meli̇h Güler, Di̇lek Varişli
Multiwall Carbon Nanotube-Supported Molybdenum Catalysts For Ammonia Decomposition Reaction Under Microwave Effect, Meli̇h Güler, Di̇lek Varişli
Turkish Journal of Chemistry
In this study, microwave-assisted ammonia decomposition reaction was investigated over molybdenum incorporated catalysts. Due to the selective, volumetric, and noncontact heating properties of the microwave system, higher conversion values could be achieved at relatively lower reaction temperatures, which is important for on-site COx-free hydrogen production. Multiwall carbon nanotube-supported molybdenum catalysts were prepared following the impregnation procedure with different metal loading (3.5%-12.5% wt%), and inductively coupled plasma, nitrogen physisorption, X-ray diffraction, and transmission electron microscopic techniques were employed to characterize the fresh and used samples. Reaction experiments were performed under the flow of pure ammonia with a gas hourly space velocity …
Gc-Ms Analysis Of The Methanolic Extracts Of Smilax China And Salix Alba And Their Antioxidant Activity, Abdul Qadir, Mohd Aqil, Athar Ali, Farhan J. Ahmad, Sayeed Ahmad, Muhammad Arif, Nausheen Khan
Gc-Ms Analysis Of The Methanolic Extracts Of Smilax China And Salix Alba And Their Antioxidant Activity, Abdul Qadir, Mohd Aqil, Athar Ali, Farhan J. Ahmad, Sayeed Ahmad, Muhammad Arif, Nausheen Khan
Turkish Journal of Chemistry
Smilax china L.(familySmilacaceae) and Salix alba L.(familySalicaceae)areplantsthathavebeentraditionally used to treat various ailments in Indian and Chinese medicine. A quantitative estimation of the methanolic extracts of these plants was performed by GC-MS analysis to obtain insight into its phytoconstituents responsible for therapeutic action. Theantioxidantpotentialofthemethanolextractsof Smilax china (MESC) and Salix alba (MESA) wereassessed with DPPH by using a UV spectrophotometer at a wavelength of 517 nm. The prevailing compounds found in MESC were lactam sugars including 2,5-dimethyl-2,4-dihydroxy-3(2H)-furanon (1.40%), 1,5-anhydro-6-deoxyhexo-2,3-diulose (4.33%), and alpha-methyl-1-sorboside (1.80%); the two alkaloids found were 1,4-methane-4,4a,5,6,7,8,9,9a-octahydro10,10-dimethyl cyclohepta[d] pyridazine (0.87%) and 1,3,7-trimethyl-2,6-dioxopurine(0.54%); terpenes included deltacadinene (0.39%), terpineol, (+)-cedrol (22.13%), 3-thujanol …
Proline-Based Organocatalyst-Mediated Asymmetric Aldol Reaction Of Acetone With Substituted Aromatic Aldehydes: An Experimental And Theoretical Study, Nevi̇n Arslan, Selami̇ Ercan, Necmetti̇n Pi̇ri̇nççi̇oğlu
Proline-Based Organocatalyst-Mediated Asymmetric Aldol Reaction Of Acetone With Substituted Aromatic Aldehydes: An Experimental And Theoretical Study, Nevi̇n Arslan, Selami̇ Ercan, Necmetti̇n Pi̇ri̇nççi̇oğlu
Turkish Journal of Chemistry
This work involves a facile synthesis of three (S)-proline-based organocatalysts with C$_{2}$ symmetry and their effects in enantioselective aldol reaction of acetone with substituted aromatic aldehydes. Moderate enantioselectivities (up to 61% ee) were obtained depending on the nature of the substituents on the aryl ring. Computational calculations at HF/6-31 + G(d) level were employed to underline the enantioselectivity imposed by all the organocatalysts. Higher calculations at B3LYP/6-311 ++ G(d,p) scrf=(solvent=dichloromethane)//B3LYP/6-31 + G(d) levels of theory were also performed for the aldol reaction of acetone with benzaldehyde and 4-nitrobenzaldehyde catalyzed by 1. The computationaloutcomeswereconsistentwiththoseproducedbyexperimentalresultsandtheywerevaluabletoelucidate the mechanism for the observed stereoselectivity.
Hydrotalcite Framework Stabilized Ruthenium Nanoparticles (Ru/Htal): Efficient Heterogeneous Catalyst For The Methanolysis Of Ammonia-Borane, İsmai̇l Burak Bağuç, Mehmet Yurderi̇, Gülşah Saydan Kanberoğlu, Ahmet Bulut
Hydrotalcite Framework Stabilized Ruthenium Nanoparticles (Ru/Htal): Efficient Heterogeneous Catalyst For The Methanolysis Of Ammonia-Borane, İsmai̇l Burak Bağuç, Mehmet Yurderi̇, Gülşah Saydan Kanberoğlu, Ahmet Bulut
Turkish Journal of Chemistry
Ruthenium nanoparticles stabilized by a hydrotalcite framework (Ru/HTaL) were prepared by following a 2-step procedure comprising a wet-impregnation of ruthenium(III) chloride precatalyst on the surface of HTaL followed by an ammonia-borane (NH$_{3}$BH$_{3}$) reduction of precatalyst on the HTaL surface all at room temperature. The characterization of Ru/HTaL was done by using various spectroscopic and visualization methods including ICP-OES, P-XRD, FTIR, $^{11}$B NMR, XPS, BFTEM, and HRTEM. The sum of the results gained from these analyses has revealed the formation of well-dispersed and highly crystalline ruthenium nanoparticles with a mean diameter of 1.27 ± 0.8 nm on HTaL surface. The catalytic …
A Comparative Study Of Silver Electrodeposition From Pyrophosphate-Cyanide And High Concentration Cyanide Electrolytes In The Presence Of Brighteners, Hati̇ce Kübra Akben, Servet İbrahi̇m Ti̇mur
A Comparative Study Of Silver Electrodeposition From Pyrophosphate-Cyanide And High Concentration Cyanide Electrolytes In The Presence Of Brighteners, Hati̇ce Kübra Akben, Servet İbrahi̇m Ti̇mur
Turkish Journal of Chemistry
A study of the electrodeposition of silver from 2 different types of electrolytes; (1) neutral pyrophosphatecyanide electrolyte and (2) alkaline high concentrated cyanide electrolyte in the presence of a variety of additives such as 2-mercaptobenzothiazole, potassium selenocyanate, and potassium antimony tartrate was performed. Influence of additives and cyanide concentration on microstructure and kinetics of the cathodic processes were studied. A brightener couple, 2-mercaptobenzothiazole and potassium antimony tartrate, were combined within this investigation anddetectedtobehighlyeffectiveforsilverelectrodeposition. Therapidincreaseincurrentdensityatthesamepotential interval related to grain refinement effect of potassium antimony tartrate was shown. The cyclic organic compound, 2mercaptobenzothiazole, polarizes the reduction to high cathodic potential in pyrophosphate …
Effect Of Various G-C3n4 Precursors On The Catalytic Performance Of Alkylorganotin-Based Catalysts In Acetylene Hydrochlorination, Yibo Wu, Fuxiang Li, Jianwei Xue, Zhiping Lv
Effect Of Various G-C3n4 Precursors On The Catalytic Performance Of Alkylorganotin-Based Catalysts In Acetylene Hydrochlorination, Yibo Wu, Fuxiang Li, Jianwei Xue, Zhiping Lv
Turkish Journal of Chemistry
A series of alkylorganotin-based catalysts (Sn-g-C$_{3}$N$_{4}$/AC) was prepared by wet impregnation in ethanol using different g-C$_{3}$N$_{4}$ precursors and alkylorganotin compounds. The structure, texture, surface composition, and adsorption properties of the as-prepared catalysts were extensively characterized. Then, the obtained samples were evaluated for their catalytic performance in hydrochlorination of acetylene. The results provided by the X-ray photoelectron spectroscopy, acetylene temperature-programmed desorption, and HCl adsorption confirmed the nature of the active sites (i.e. Sn-N$_{x}$ ) involved in the reactant adsorption, and hence in the improved catalytic performance. These active sites were also related to the improved lifetime of alkylorganotin-based catalysts in the …
The Single Nucleotide Ss-Arrestin2 Variant, A248t, Resembles Dynamical Properties Of Activated Arrestin, Özge Şensoy
The Single Nucleotide Ss-Arrestin2 Variant, A248t, Resembles Dynamical Properties Of Activated Arrestin, Özge Şensoy
Turkish Journal of Chemistry
ß-arrestins are responsible for termination of G protein-coupled receptor (GPCR)-mediated signaling. Association of single nucleotide variants with onset of crucial diseases has made this protein family hot targets in the field of GPCR-mediated pharmacology. However, impact of these mutations on function of these variants has remained elusive. In this study, structural and dynamical properties of one of ß-arrestin2 (arrestin 3) variants, A248T, which has been identified in some cancer tissue samples, were investigated via molecular dynamics simulations. The results showed that the variant underwent structural rearrangements which are seen in crystal structures of active arrestin. Specifically, the "short helix" unravels …
Preparation And Characterization Of Form-Stable Phase Change Material/End-Of-Life Tires Composites For Thermal Energy Storag, Yeli̇z Konuklu
Preparation And Characterization Of Form-Stable Phase Change Material/End-Of-Life Tires Composites For Thermal Energy Storag, Yeli̇z Konuklu
Turkish Journal of Chemistry
The management of end-of-life tires (ELT) waste gains importance in aspect of possible environmental and economic issues so the waste recycling becomes unavoidable. This study describes the fabrication and characterization of a new phase changing material (PCM)/ELT microcomposites that could be used in thermal energy storage. Paraffin together with the 4 fatty acids and ELT rubber powder are used as PCMs and as the supporting material, respectively. Paraffin/ELT composites are fabricated, as well, by the vacuum impregnation method in order to investigate the effect of the preparation method. The thermal, morphological, and chemical properties of the prepared PCM/ELT rubber microcomposites …
Sensitive Determination Of Hydrogen Peroxide In Real Water Samples By High Spin Peroxo Complex, Tuğba Yavuz, Levent Peli̇t
Sensitive Determination Of Hydrogen Peroxide In Real Water Samples By High Spin Peroxo Complex, Tuğba Yavuz, Levent Peli̇t
Turkish Journal of Chemistry
In this paper, a fast, cheap, simple, sensitive and selective spectrophotometric method based on high spin peroxo-Fe(III)-EDTAcomplexinthealkalinemediumwasdevelopedforthedeterminationofhydrogenperoxide(H$_{2}$O$_{2}$) in real water samples. The purple-coloured complex with a maximum absorbance at a wavelength of 525 nm was formed. Various parameters such as type of stabilizer reagent and its concentration, reaction time, Fe(III), EDTA and NH3 concentration were optimized. The method was confirmed with the Beer?s law with a molar absorption coefficient of267.36Lmol$^{-1}$ cm$^{-1}$ in the 8.3×10$^{-6}$ -4.08×10$^{3}$ mol/L concentrationrange. Sandell's sensitivityoftheproposed method was also calculated as 0.188 µg/cm2. LOD and LOQ were determined as 2.5 ×10$^{-6}$ and 8.3 ×10$^{-6}$ mol/L, respectively. Intraday …
Preparation And Catalytic Evaluation Of Au/ Γ-Al2o3nanoparticles For The Conversion Of 4-Nitrophenol To 4-Aminophenol By Spectrophotometric Metho, Farhat Saira, Naveeda Firdous, Rumana Qureshi, Ayesha Ihsan
Preparation And Catalytic Evaluation Of Au/ Γ-Al2o3nanoparticles For The Conversion Of 4-Nitrophenol To 4-Aminophenol By Spectrophotometric Metho, Farhat Saira, Naveeda Firdous, Rumana Qureshi, Ayesha Ihsan
Turkish Journal of Chemistry
A set of catalysts having gold nanoparticles deposited on γ-Al$_{2}$O$_{3}$ ( Au/ γ-Al2O3) with lowest effective amount of gold content were prepared by successive impregnation and hydrogen reduction method. The structural featuresof prepared catalysts were analysed byX-ray diffraction(XRD), N2 physisorption, scanning electron microscopy (SEM), and Fourier transform infrared (FTIR). The catalytic activity was evaluated for the reduction of an organic pollutant 4-nitrophenol (4NP) to 4-aminophenol (4AP) by spectrophotometric analysis. Supported catalyst presented excellent catalytic ability to convert 4NP to 4AP in the presence of sodium borohydride (SBH) due to synergistic effect of Au NPs and mesoporous γ-Al$_{2}$O$_{3}$ support. The reduction …
Development Of A Biosensor Platform Based On Ito Sheets Modified With 3-Glycidoxypropyltrimethoxysilane For Early Detection Of Trap1, Berfi̇n Vural, Meltem Çalişkan, Mustafa Kemal Sezgi̇ntürk
Development Of A Biosensor Platform Based On Ito Sheets Modified With 3-Glycidoxypropyltrimethoxysilane For Early Detection Of Trap1, Berfi̇n Vural, Meltem Çalişkan, Mustafa Kemal Sezgi̇ntürk
Turkish Journal of Chemistry
The aim of this research was to design an electrochemical immunosensor for determination of tumour necrosis factor receptor-associated protein-1(TRAP1) antigen, a heat shock protein linked to tumour necrosis factor. The indium-tin oxide covered polyethylene terephthalate (ITO-PET) electrode surface was cleaned and was prepared for the introduction of hydroxyl groups on its surface by using NH$_{4}$ OH/H$_{2}$O$_{2}$/H$_{2}$O. As a silanization agent for covalent attachment of anti-TRAP1 on the surface of the ITO working electrode, 3-glycidoxypropyltrimethoxysilane (3-GOPS) was used. Cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) were used to characterize the immobilization steps. A variety of parameters, 3-GOPS and anti-TRAP1 concentrations, …
Investigation Of The Effect Of Pan And Pan/Zno Photocatalysts On 100% Degradation Of Congo Red Under Uv Visible Light Irradiation And Lightless Environment, Si̇bel Zor, Bi̇lge Budak
Investigation Of The Effect Of Pan And Pan/Zno Photocatalysts On 100% Degradation Of Congo Red Under Uv Visible Light Irradiation And Lightless Environment, Si̇bel Zor, Bi̇lge Budak
Turkish Journal of Chemistry
PAn (polyaniline) and PAn/ZnO photocatalysts were synthesized using chemical polymerization of aniline. The structure characterization of the synthesized samples was analysed by using X-ray diffraction (XRD), Fourier transforminfraredspectroscopy(FT-IR),scanningelectronmicroscopy(SEM),transmissionelectronmicroscopy(TEM), and UV-Vis spectroscopy measurements, and thermal gravimetric analysis (TGA). The photocatalytic activities of PAn and PAn/ZnO (0.1g/100ml) on the degradation of the Congo red (CR) dye were studied under the UV visible light irradiation and the lightless environment and the efficiency of catalysts have been explained in details. Contribution of UV visible light irradiation on the 100% degradation of CR dye for the PAn and PAn/ZnO photocatalyst is determined. The reaction kinetics …
Combined Computational And Experimental Studies On Cysteine-Sulfadiazine Adduct Formation, Nursel Açar Selçuki̇, Emi̇ne Coşkun, Ender Bi̇çer
Combined Computational And Experimental Studies On Cysteine-Sulfadiazine Adduct Formation, Nursel Açar Selçuki̇, Emi̇ne Coşkun, Ender Bi̇çer
Turkish Journal of Chemistry
The electrochemical characterization of sulfadiazine-cysteine (SD-CYS) adduct formation was performed in phosphatebuffer(pH7)onthebasisofvoltammetriccurrentandpeakpotentialmeasurements. Duetotheassociationof cysteine with sulfadiazine, the reduction peak currents of mercuric and mercurous cysteine thiolates decreased and their peak potentials simultaneously shifted to less negative potentials. By using the current changes of mercurous cysteine thiolate, it was determined that cysteine and sulfadiazine are associated with a 1:1 stoichiometry with a conditional association constant of 1.99 ×10$^{4}$ M$^{-1}$. In addition to experimental studies, a computational approach was carried out to study the geometrical parameters, electron densities, and UV-Vis absorption spectra of sulfadiazine and SDCYS adduct in water. Calculated (B3LYP/6-311++G(d,p) level) …
Design Of An Amphiphilic Hyperbranched Core/Shell-Type Polymeric Nanocarrier Platform For Drug Delivery, Ayça Bal Öztürk, Nesri̇n Oğuz, Hande Tekarslan Şahi̇n, Serkan Emi̇k, Emi̇ne Alarçi̇n
Design Of An Amphiphilic Hyperbranched Core/Shell-Type Polymeric Nanocarrier Platform For Drug Delivery, Ayça Bal Öztürk, Nesri̇n Oğuz, Hande Tekarslan Şahi̇n, Serkan Emi̇k, Emi̇ne Alarçi̇n
Turkish Journal of Chemistry
An amphiphilic core/shell-type polymer-based drug carrier system (HPAE- PCL-b-MPEG), composed of hyperbranched poly(aminoester)-based polymer (HPAE) as the core building block and poly(ethylene glycol)-bpoly(ε-caprolactone) diblock polymers (MPEG-b-PCL) as the shell building block, was designed. The synthesized polymers were characterized with FTIR, $^{1}$H NMR, $^{13}$C NMR, and GPC analysis. Monodisperse HPAE-PCL-bMPEG nanoparticles with dimensions of
Fabrication And Biocompatibility Assessment Of Polypyrrole/Cobalt(Ii) Metal-Organic Frameworks Nanocomposite, Mehrnaz Mehrabani, Zeinab Ansari Asl, Farzaneh Rostamzadeh, Saeideh Jafarinejad Farsangi, Mahnaz Sadat Hashemi, Mozhgan Sheikholeslami, Zeinab Neisi
Fabrication And Biocompatibility Assessment Of Polypyrrole/Cobalt(Ii) Metal-Organic Frameworks Nanocomposite, Mehrnaz Mehrabani, Zeinab Ansari Asl, Farzaneh Rostamzadeh, Saeideh Jafarinejad Farsangi, Mahnaz Sadat Hashemi, Mozhgan Sheikholeslami, Zeinab Neisi
Turkish Journal of Chemistry
Nowadays, metal-organic frameworks (MOFs) have emerged as promising tools for different biological applications and therefore, efforts are ongoing to develop more biocompatible MOFs-based nanocomposites. We aimed to fabricate some new conductive nanocomposites of polypyrrole and cobalt-MOF with different weight percentages (PPy/x%Co-MOF)usingthesolutionmixingmethodandcharacterizethemthroughFT-IR(Fourier-transforminfrared), PXRD (powder X-ray diffraction), SEM (scanning electron microscope), and TEM (transmission electron microscope) techniques. The biocompatibility of nanocomposites was assessed by haemolytic, cytotoxic, and quantitative reverse transcription PCR (qRT-PCR) assays. FT-IR and PXRD results revealed that nanocomposites consisted of pure MOFs and PPy. Moreover, SEM results indicated their spherical morphology along with an average diameter of 190 nm. (3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium …
Arene Diazonium Saccharin Intermediates: A Greener And Cost-Effective Alternative Method For The Preparation Of Aryl Iodide, Lia Zaharani, Nader Ghaffari Khaligh, Zohreh Shahnavaz, Mohd Rafie Johan
Arene Diazonium Saccharin Intermediates: A Greener And Cost-Effective Alternative Method For The Preparation Of Aryl Iodide, Lia Zaharani, Nader Ghaffari Khaligh, Zohreh Shahnavaz, Mohd Rafie Johan
Turkish Journal of Chemistry
In the current protocol, the arene diazonium saccharin derivatives were initially produced from various substituted aromatic amines; subsequently, these intermediates were treated with a greener organic iodide for the preparation of the aryl iodide. We tried to choose low-cost, commercially available, biodegradable, recoverable, ecofriendly, and safe reagents and solvents. The arene diazonium saccharin intermediates could be stored in the liquid phase into a refrigerator for a long time with no significant loss activity. The outstanding merits of the current protocol (a) included the partial recovering of saccharin and tetraethylammonium salt, (b) reduce the use of solvents and the reaction steps …
Phosphorus-Nitrogen Compounds- (Part 50): Correlations Between Structural Parameters For Cylophosphazene Derivatives Containing Ferrocenyl Pendant Arm(S), Nuran Asmafi̇li̇z, Gamze Elmas, Aytuğ Okumuş, Selen Bi̇lge Koçak, Zeynel Kiliç
Phosphorus-Nitrogen Compounds- (Part 50): Correlations Between Structural Parameters For Cylophosphazene Derivatives Containing Ferrocenyl Pendant Arm(S), Nuran Asmafi̇li̇z, Gamze Elmas, Aytuğ Okumuş, Selen Bi̇lge Koçak, Zeynel Kiliç
Turkish Journal of Chemistry
The results of a systematic study of spiro-cyclotri/tetraphosphazenes with ferrocenyl pendant arm on the basis of correlation between structural parameters were presented. The main parameters were obtained from Xray crystallography and 31 P NMR results in order to investigate the relationship between the δ P$_{spiro}$ shift values and endocyclic and exocyclic NPN bond angles, and electron density transfer parameters. Structural parameters derived from 11 types of the ferrocenyl cyclophosphazene derivatives with 5- to 7-membered spiro-rings introduced to the literature from our research group were studied and compared with each other.
Hosphorus-Nitrogen Compounds (Part 51): The Relationship Between Spectroscopic And Crystallographic Data Of Mono- And Di-Spirocyclophosphazene Derivatives With 4-Fluoro/Nitrophenylmethyl Pendant Arm/Arms, Aytuğ Okumuş, Gamze Elmas, Nuran Asmafi̇li̇z, Selen Bi̇lge Koçak, Zeynel Kiliç
Hosphorus-Nitrogen Compounds (Part 51): The Relationship Between Spectroscopic And Crystallographic Data Of Mono- And Di-Spirocyclophosphazene Derivatives With 4-Fluoro/Nitrophenylmethyl Pendant Arm/Arms, Aytuğ Okumuş, Gamze Elmas, Nuran Asmafi̇li̇z, Selen Bi̇lge Koçak, Zeynel Kiliç
Turkish Journal of Chemistry
A great wealth of structural information about phosphazenes can be gleaned from the combined spectroscopic and crystallographic data. When data from $^{31}$P NMR spectroscopy and X-ray crystallography are put together like pieces in a puzzle, a number of correlations can be obtained for phosphazene derivatives. A systematic study concerning the correlations among the structural parameters (e.g., $^{31}$P NMR data, endocyclic/exocyclic NPN bond angles and bond lengths) revealed some characteristics of mono- and di-spirocyclophosphazene derivatives bearing~4-fluoro/nitrophenylmethyl pendant arm/arms. These correlations include the relationship between the $\delta $P$_{spiro}$ shifts, the values of electron density transfer parameters $\Delta $(P--N), and the endocyclic and …
Combined Ligand And Structure-Based Virtual Screening Approaches For Identification Of Novel Ache Inhibitors, Kader Şahi̇n, Serdar Durdaği
Combined Ligand And Structure-Based Virtual Screening Approaches For Identification Of Novel Ache Inhibitors, Kader Şahi̇n, Serdar Durdaği
Turkish Journal of Chemistry
The excessive activity of acetylcholinesterase enzyme (AChE) causes different neuronal problems, especially dementia and neuronal cell deaths. Food and Drug Administration (FDA) approved drugs donepezil, rivastigmine, tacrine and galantamine are AChE inhibitors and in the treatment of Alzheimer's disease (AD) these drugs are currently prescribed. However, these inhibitors have various adverse side effects. Therefore, there is a great need for the novel selective AChE inhibitors with fewer adverse side effects for the effective treatment. In this study, combined ligand-based and structure-based virtual screening approaches were used to identify new hit compounds from small molecules library of National Cancer Institute (NCI) …
Syntheses And Antibacterial Activities Of 4 Linear Nonphenolic Diarylheptanoids, Şemsi̇ Betül Demi̇r, Hati̇ce Seçi̇nti̇, Nesli̇han Çelebi̇oğlu, Murat Özdal, Alev Sezen, Özlem Gülmez, Ömer Faruk Algur, Hasan Seçen
Syntheses And Antibacterial Activities Of 4 Linear Nonphenolic Diarylheptanoids, Şemsi̇ Betül Demi̇r, Hati̇ce Seçi̇nti̇, Nesli̇han Çelebi̇oğlu, Murat Özdal, Alev Sezen, Özlem Gülmez, Ömer Faruk Algur, Hasan Seçen
Turkish Journal of Chemistry
Four linear nonphenolic diarylheptanoids were synthesized and their antibacterial activities were studied. ($S)$-2-Me-CBS-catalysed reduction of alnustone with BH$_{3}$.SMe$_{2}$ gave ($R)$(-)(4$E$,6$E)$-1,7-diphenylhepta-4,6-dien-3-ol, a natural product. Reduction of alnustone with Na in t-BuOH at -15 $^{\circ}$C under NH$_{3}$ atm gave ($E)$-1,7-diphenylhept-5-en-3-one as a Birch-type reduction product. $t$-BuOK catalysed condensation of benzalacetone with propionyl chloride gave (4$Z$,6$E)$-5-hydroxy-1,7-diphenylhepta-4,6-dien-3-one, a natural product. (1$E$,4$Z$,6$E)$-5-Hydroxy-4-phenethyl-1,7-diphenylhepta-1,4,6-trien-3-one, a curcuminoid, was synthesized starting from pentan-2,4-dione in 3 steps. The synthesized chemical compounds were applied against 2 gram-positive bacteria (Bacillus cereus and Arthrobacter agilis), 4 gram-negative bacteria (Pseudomonas aeruginosa, Xanthomonas campestris, Klebsiella oxytoca and Helicobacter pylori), and 1 yeast (Candida albicans) by …
Analysis Of Electrochemical Impedance Spectroscopy Response For Commercial Lithium-Ion Batteries: Modeling Of Equivalent Circuit Elements, Uğur Morali, Sali̇m Erol
Analysis Of Electrochemical Impedance Spectroscopy Response For Commercial Lithium-Ion Batteries: Modeling Of Equivalent Circuit Elements, Uğur Morali, Sali̇m Erol
Turkish Journal of Chemistry
Electrochemical impedance spectroscopy measurements were performed to capture the physically meaningful parameters of commercially available 18650 cylindrical and 2032 coin cells by using the equivalent circuit model. The impedance response of the batteries was systematically investigated and discussed. A detailed analysis was achieved providing a determination of influential factors on the equivalent circuit parameters. The results suggested that the cell type tested here influenced the equivalent circuit elements profoundly. Taguchi analysis indicated that state-of-charge had the highest effect on the cathodic constant-phase-element exponent. The results contribute to full electrochemical analysis that is required for battery characterization.
Mesoporous Starch Aerogels Production As Drug Delivery Matrices: Synthesis Optimization, Ibuprofen Loading, And Release Property, Akbar Mohammadi, Jafar Sadegh Moghaddas
Mesoporous Starch Aerogels Production As Drug Delivery Matrices: Synthesis Optimization, Ibuprofen Loading, And Release Property, Akbar Mohammadi, Jafar Sadegh Moghaddas
Turkish Journal of Chemistry
he aim of this work was to prepare biodegradable starch aerogels as drug carriers. The effective parameters in the synthesis and the optimal values of these parameters were determined using Minitab experimental design software. Ibuprofen was selected as a model drug for the dissolution study and loaded into optimized aerogel during the last solvent exchange step. The Fourier Transform Infrared Spectroscopy (FTIR) analysis showed that ibuprofen has been successfully loaded into the aerogel matrix without any effect on the aerogel nature. The drug loading was calculated to be 29%. The isotherm of ibuprofen adsorption into aerogels matrices followed from the …
Effect Of Polyelectrolyte Complex Formation On The Antibacterial Activity Of Copolymer Of Alkylated 4-Vinylpyridine, Murat Topuzoğullari
Effect Of Polyelectrolyte Complex Formation On The Antibacterial Activity Of Copolymer Of Alkylated 4-Vinylpyridine, Murat Topuzoğullari
Turkish Journal of Chemistry
Polymers bearing quaternized 4-vinylpyridine (QVP) groups are known for their antibacterial activities and these polymers can form polyelectrolyte complexes (PEC) with polyanions through electrostatic interactions. PEC formation can be used to adjust the antibacterial activity of polymers of QVP, deliver active molecules, or design antibacterial supramolecular structures. However, the antibacterial activity of PECs of QVP polymers has not been investigated. In this study, a copolymer of QVP was mixed with polyacrylic acid in various molar ratios of components to form PECs. Hydrodynamic diameters and zeta potentials of formed PECs were determined by dynamic and electrophoretic light scattering spectroscopy techniques. The …
Development And Validation Of An Hplc Method For Determination Of Rofecoxib In Bovine Serum Albumin Microspheres, Esra Demi̇rtürk, Emi̇rhan Nemutlu, Selma Şahi̇n, Levent Öner
Development And Validation Of An Hplc Method For Determination Of Rofecoxib In Bovine Serum Albumin Microspheres, Esra Demi̇rtürk, Emi̇rhan Nemutlu, Selma Şahi̇n, Levent Öner
Turkish Journal of Chemistry
A simple and reliable HPLC method was developed and validated for determination of rofecoxib in bovine serum albumin microsphere. The analyses were performed on a C18 column (150 x 4.6 mm, 5 μm particle size) at room temperature with UV detection at 272 nm. The mobile phase was composed of acetonitrile-0.1% o-phosphoric acid solution in water (1:1, v/v) mixture, and flow rate was set to 1 mL/min. The method was validated according to the international guidelines with respect to stability, linearity range, limit of quantitation and detection, precision, accuracy, specificity, and robustness. The detection and quantification limit of the method …
A Novel Fluorimetric Method For Determination Of Pseudoephedrine Hydrochloridein Pharmaceutical Formulations And Blood Serum, Nazli Farajzadeh, Nasrin Ranjbar Nader
A Novel Fluorimetric Method For Determination Of Pseudoephedrine Hydrochloridein Pharmaceutical Formulations And Blood Serum, Nazli Farajzadeh, Nasrin Ranjbar Nader
Turkish Journal of Chemistry
An inexpensive, simple, highly sensitive, and rapid fluorimetric method was developed for the analysis of pseudoephedrine hydrochloride at trace levels. The method is based on the recovery of fluorescence of Rh6G dye due to the interaction of pseudoephedrine hydrochloride with Rh6G-Au NPs complex, which results in the release of Rh6G from the complex and halting fluorescence resonance energy transfer between Rh6G and Au NPs. The intensity of fluorescence was directly proportional to the concentration of the analyte, which was used for its determination. Experimental factors were optimized by response-surface methodology. Under optimum conditions, the calibration curve was linear over the …
Allylphenoxypiperidinium Halides As Corrosion Inhibitors Of Carbon Steel And Biocides, Gunay Mehdiyeva Muzakir, Musa Bairamov Rza, Shahnaz Hosseinzadeh Bahador, Gulnara Hasanova Musa
Allylphenoxypiperidinium Halides As Corrosion Inhibitors Of Carbon Steel And Biocides, Gunay Mehdiyeva Muzakir, Musa Bairamov Rza, Shahnaz Hosseinzadeh Bahador, Gulnara Hasanova Musa
Turkish Journal of Chemistry
A series of 1-(4-(2-allylphenoxy)butyl)piperidin-1-ium halides (4a-d) was synthesized and characterized via spectroscopic methods (FTIR, $^{1}$H NMR). The corrosion inhibition of the synthesized halides on carbon steel in water-salt-hydrocarbon environment, saturated with H$_{2}$S, was investigated. For this purpose, a series of techniques such as gravimetric measurement, potentiodynamic polarisation, and scanning electron microscope (SEM) were used and some thermodynamic parameters of corrosion process ($\Delta G_{ads.}$, $\Delta H^{0}_{ads.}$, $\Delta S^{0}_{ads.})$ were evaluated. The steel surface was checked by SEM, and the steel surface showed good surface coverage. The results showed that the synthesized compounds at the concentrations 125, 150 mg x L$^{-1}$ have …
Synthesis And Effect Of Substituent Position, Metal Type On The Electrochemical Properties Of (3-Morpholin-4-Ylpropoxy) Groups Substituted Cobalt, Manganese Phthalocyanines, Zekeri̇ya Biyiklioğlu, Hüseyi̇n Baş
Synthesis And Effect Of Substituent Position, Metal Type On The Electrochemical Properties Of (3-Morpholin-4-Ylpropoxy) Groups Substituted Cobalt, Manganese Phthalocyanines, Zekeri̇ya Biyiklioğlu, Hüseyi̇n Baş
Turkish Journal of Chemistry
In this work, 4-(3-morpholin-4-ylpropoxy)phthalonitrile 2, 3-(3-morpholin-4-ylpropoxy)phthalonitrile 3, Co(II)Pc and Mn(III)Pcs containing (3-morpholin-4-ylpropoxy) groups at peripheral and nonperipheral positions were synthesized. Phthalonitrile derivatives (2 and 3), Co(II)Pc and Mn(III)Pcs (2a, 2b, 3a, 3b) were characterized by using FT-IR, NMR (only for 2 and 3), mass and UV-Vis (except 2 and 3) spectral data techniques. Also, electrochemistry of (3-morpholin-4-ylpropoxy) group substituted Co(II)Pc and Mn(III)Pcs were inspected by using cyclic voltammetry. Electrochemical studies show that (3-morpholin-4-ylpropoxy) group substituted Co(II)Pc and Mn(III)Pcs electropolymerized on the Pt working electrode.
Gas Phase Polymerization Of Ethylene Towards Uhmwpe, Gözde Geçi̇m, Ertuğrul Erkoç
Gas Phase Polymerization Of Ethylene Towards Uhmwpe, Gözde Geçi̇m, Ertuğrul Erkoç
Turkish Journal of Chemistry
For the first time, ultra-high molecular weight polyethylene (UHMWPE) was produced in gas phase process with a new fluidized bed concept where the solids are dispersed phase and the gas is bulk phase as opposed to conventional fluidized bed reactors (FBRs). With this concept, UHMWPE with average molecular weights about 1-6,9$\, \times \, $10$^{6}$ g moles$^{-1}$ were produced with a commercial supported Ziegler-Natta catalyst by using a gas phase mini semibatch reactor system. Additionally, optimum conditions of gas phase polymerization for the best results of productivity, catalyst activity, molecular weight and crystallinity were determined by Taguchi experimental design and catalyst …