Scopus İndeksli Yayınlar Koleksiyonu / Scopus Indexed Publications Collection
Permanent URI for this collectionhttps://hdl.handle.net/11147/7148
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Article Hydrothermal Synthesis of Zeolite T From Bentonite Clay: Catalytic Applications and Molecular Docking Analysis(National Information & Documentation Centre-NIDOC, 2025) Taib, H.; Lefrada, L.; Belfennache, D.; Belghit, M. Y.; Benbouzid, M.; Yilmaz, S.; A.Ali, MohamedZeolites are essential materials in modern industries due to their uses as cation exchangers, selective adsorbents, and catalysts. In this study,we report novel procedures for producing zeolite T, which is distinguished by its round crystals that closely resemble Saharan flowers. An investigation was conducted on the hydrothermal synthesis of T zeolite in alkaline aqueous solutions without templates. Zeolite T crystals were synthesized via hydrothermal methods with clay-based aluminosilicate gel containing 1Al2O3, 25SiO2, 6.5Na2O, 2.25K2O, and 350 H2O. Zeolite crystals were formed at a temperature of 130 degrees C, with crystallization durations of 3 and 5 days, respectively, using processed natural bentonite clay as the starting material. A range of analytical methods, such as XRD, FTIR, Raman, SEM, ATD-EDX, BET, ATG, and NH3-TPD, were used to observe the crystallization stages of zeolite T grains.During the synthesis of Zeolite T, samples were collected at various intervals, with the samples taken after three and five days of reaction being particularly noteworthy. The T1 zeolite is identified as a mixture of T2 zeolite and other impurities present in the reaction medium, indicating that T1 zeolite serves as a precursor phase to T2 zeolite (T1 is a germination phase). The analysis revealed that a treatment temperature of 130 degrees C for 5 days is optimal. The nucleation of zeolite T from treated bentonite commenced after 3 days. The results indicate that zeolite T2, composed of uniform crystalline grains formed over 5 days, yields a mesoporous structure with a size of 1.35 mu m and a molar ratio of 1.78 between molar quantities of silica and aluminum of this zeolite (T Zeolite). An analysis of the BET (surface area) revealed a value of 95.75 m2g-1, accompanied by a pore volume of 0.010 cm3g-1. Moreover, the examination of TPD-NH3 desorption revealed a restricted occurrence of the acidic site of Br & oslash;nsted, while a significant number of acidic sites of Lewis were detected. The obtained crystalline zeolite T was examined for its ability to catalyze the Hantzsch reaction. In addition, T2 zeolite prepared was used as a catalyst in the synthesis of the 1,1'-(4-(5-bromo-2-thiophenyl)-2,6-dimethyl-1,4-dihydropyridine-3,5-diyl)bis(ethan-1-one) (BTDDB) due to the acidity sites (Lewis and Br & oslash;nsted acid) in the structure of the zeolite. The result of the reaction has shown a good percentage in the synthetic of BTDDB The results of FTIR, UV, 13C NMR, and 1H NMR spectrum analyses revealed that the structure of the 1,4-dihydropyridine compound was well-defined, and the use of molecular docking and density functional theory (DFT) analysis revealed better performance in the inhibition of the macromolecular targets aminodeoxyfutalosine nucleosidase and DNA gyrase subunit B.Article Citation - WoS: 38Citation - Scopus: 36Structural Studies of Geosmin Synthase, a Bifunctional Sesquiterpene Synthase With ?? Domain Architecture That Catalyzes a Unique Cyclization-Fragmentation Reaction Sequence(American Chemical Society, 2015) Harris, Golda G.; Lombardi, Patrick M.; Pemberton, Travis A.; Matsui, Tsutomu; Weiss, Thomas M.; Cole, Kathryn E.; Köksal, Mustafa; Murphy, Frank V.; Vedula, L. Sangeetha; Chou, Wayne K. W.; Cane, David E.; Christianson, David W.Geosmin synthase from Streptomyces coelicolor (ScGS) catalyzes an unusual, metal-dependent terpenoid cyclization and fragmentation reaction sequence. Two distinct active sites are required for catalysis: the N-terminal domain catalyzes the ionization and cyclization of farnesyl diphosphate to form germacradienol and inorganic pyrophosphate (PPi), and the C-terminal domain catalyzes the protonation, cyclization, and fragmentation of germacradienol to form geosmin and acetone through a retro-Prins reaction. A unique αα domain architecture is predicted for ScGS based on amino acid sequence: each domain contains the metal-binding motifs typical of a class I terpenoid cyclase, and each domain requires Mg2+ for catalysis. Here, we report the X-ray crystal structure of the unliganded N-terminal domain of ScGS and the structure of its complex with three Mg2+ ions and alendronate. These structures highlight conformational changes required for active site closure and catalysis. Although neither full-length ScGS nor constructs of the C-terminal domain could be crystallized, homology models of the C-terminal domain were constructed on the basis of 36% sequence identity with the N-terminal domain. Small-angle X-ray scattering experiments yield low-resolution molecular envelopes into which the N-terminal domain crystal structure and the C-terminal domain homology model were fit, suggesting possible αα domain architectures as frameworks for bifunctional catalysis. © 2015 American Chemical Society.Article Citation - WoS: 30Citation - Scopus: 30Glycidyl-Methacry Late-Based Electrospun Mats and Catalytic Silver Nanoparticles(John Wiley and Sons Inc., 2008) Demir, Mustafa Muammer; Uğur, Gökçe; Gülgün, Mehmet A.; Menceloğlu, Yusuf Z.P(AN-GMA) and PGMA fibers coated with monodisperse silver nanoparticles have been prepared by a combination of electrospinning and electroless plating. The morphology of the electrospun fibers remains unchanged after surface hydrazination. Oxidation of hydrazine in an ammoniacal solution of AgNO 3 reduces and deposits silver atoms along the fiber surface, which then coalesce to Ag particles. The size of the silver nanoparticles is varied between 20-60 nm. Since the density of the active sites for silver reduction is lower in P(AN-GMA), a smaller particle size could be obtained. The catalytic activity of the silver nanoparticles has been confirmed.