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, Mohamed
    Zeolites 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: 1
    Citation - Scopus: 1
    Hydrothermal Synthesis, Characterization and Catalytic Activities of a Keggin Structure of (4,4′-Bpyh2)3[pw12o40]2•3h2o and a Wells-Dawson Structure of (4,4′-Bpyh2)3(4,4′
    (Elsevier, 2025) Ece, Ozlem; Chilufya, Langson; McMillen, Colin D.; Emirdag-Eanes, Mehtap
    Two novel polyoxometalates composed of heteropolytungstates, (4,4 '-bpyH2)3[PW12O40]2 center dot 3H2O (1) and (4,4 '- bpyH2)3(4,4 '-bpyH)1.75[Cu(bpy)2]0.25[H2P2W18O62]2 (2) have been synthesized under hydrothermal conditions and characterized by single crystal X-ray diffraction and TGA methods. Compound 1 crystallizes in the cubic space group Ia-3with a = 25.9356(12) angstrom, b = 25.936(3) angstrom, c = 25.936(3) angstrom, alpha = 90.00, (3= 90.00, gamma= 90.00 and Z = 8, and compound 2 crystallizes in the triclinic space group P-1with a = 13.5194(17) angstrom, b = 22.400(3) angstrom, c = 27.374(4) angstrom, alpha = 79.833(3), (3= 77.439(3), gamma= 80.213(4) and Z = 2. In addition to structural characterization, the catalytic activities of 1 and 2 were determined in hydrolysis reactions. In the catalytic study, starch hydrolysis reactions were performed by using hydrothermal synthesis, and starch was hydrolyzed successfully at 150 degrees C, 5 h, based on the results of Lugol's test, which highest conversion yields above 90 wt.% under optimum reaction conditions. FT-IR analysis and catalyst reusability tests were also performed for each compound. No appreciable loss was observed in activity after five reaction cycles.
  • Article
    Citation - WoS: 19
    Citation - Scopus: 21
    Synthesis and Additive Manufacturing of Calcium Silicate Hydrate Scaffolds
    (Elsevier, 2021) Oğur, Ezgi; Botti, Renata; Bortolotti, Mauro; Colombo, Paolo; Ahmetoğlu, Çekdar Vakıf
    A Calcium silicate hydrate (CSH) powder containing above 60 wt% xonotlite (remaining being tobermorite, scawtite and calcite) were produced from lime and ordinary recycled soda-lime glass via simple hydrothermal synthesis route. The thermogravimetric analysis demonstrated only similar to 20%weight loss up to 800 degrees C (at about the transformation temperature of CSHs to wollastonite), reaching a plateau in the 800-1200 degrees C temperature range. The synthesized CSH powder was employed for the fabrication of both green and heat-treated scaffolds by additive manufacturing (AM), possessing a high porosity (>80 vol%) and limited strength (similar to 0.9 MPa). (c) 2021 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).
  • Article
    Citation - WoS: 7
    Citation - Scopus: 7
    Hydrothermal Synthesis of New Rare Earth Silicate Fluorides: a Novel Class of Polar Materials
    (Academic Press Inc., 2012) McMillen, Colin D.; Eanes, Mehtap; Stritzinger, Jared T.; Kolis, Joseph K.
    Polar crystals provide an interesting avenue for materials research both in the structures they form and the properties they possess. This work describes the hydrothermal synthesis and structural characterization of three novel silicate fluorides. Compound (1), LiY 3(SiO 4) 2F 2 crystallizes in space group C2/c, with a=17.651(4) Å, b=4.8868(10) Å, c=11.625(2) Å and β=131.13(3)°. BaY 2(Si 2O 7)F 2 (2) crystallizes in space group P-1, with a=5.1576(10) Å, b=6.8389(14) Å, c=11.786(2) Å, α=93.02(3)°, β=102.05(3)° and γ=111.55(3) °. Finally, the structure of Ba 2Y 3(SiO 4) 2F 5 (3) was determined in the polar orthorhombic space group Pba2, having unit cell parameters a=8.8864(18) Å, b=12.764(3) Å and c=5.0843(10) Å. The structures are compared based on their building blocks and long range polarities. Aligned silicate tetrahedra segregated into a single layer in (3) impart the observed polarity.
  • Article
    Citation - WoS: 5
    Citation - Scopus: 5
    Hydrothermal Synthesis and Characterization of One Dimensional Chain Structures of Monolacunary Keggin Polyoxoanions Substituted With Copper
    (Elsevier Ltd., 2015) Eanes, Mehtap; Önen, Banu; McMillen, Colin D.
    Two novel polymeric polyoxometallates constructed from transition metal substituted heteropolytungstates, [(4,4’bpyH2)2(4,4’bpyH)][PCuW11O39]·H2O (1), and [(4,4’bpyH2)(pyH)3][PCuW11O39]·2H2O (2), (4,4’bpy = 4,4’bipyridine, py = pyridine) have been synthesized under hydrothermal conditions and characterized by IR, TGA, single crystal X-ray diffraction and magnetic measurements. The product formation showed a high sensitivity toward experimental factors including pH and stirring. Compounds 1 crystallizes in the monoclinic space group P2(1)/n with a = 13.503(3) Å, b = 26.726(5) Å, c = 15.168(3) Å, = 99.61(3)° and Z=4. The second compound also crystallizes in space group P2(1)/n, but with a = 13.519(3) Å, b = 20.431(4) Å, c =18.655(4) Å, = 96.52(3)° and Z=4. Compound 1 exhibits a zigzag chain structure, while compound 2 exhibits a straight chain structure. Compound 2 is the first example of a polyoxometallate containing 1D chains of transitionmetal- substituted heteropolytungstate designed with two significantly different organic units as the countercations. The Cu2+ ions in 1 exhibit paramagnetic behavior.
  • Article
    Citation - WoS: 4
    Citation - Scopus: 4
    Hydrothermal Synthesis and Characterization of a Novel Supramolecular Hybrid Based on Keggin and Cu(i) Complex
    (Elsevier, 2013) Eanes, Mehtap; Önen, Banu
    A novel inorganic-organic hybrid molecule, [Cu(4,4′bipyH)3(4,4bipy)][HPW12O40]2.12H2O (1), has been hydrothermally synthesized and characterized by IR spectra, TG and single crystal X-ray diffraction analyses. Structural analysis reveals that the novel compound 1 composed of two Kegging polyoxoanion connected with Cu complex fragment forming a big molecule that extends in 3D via hydrogen bonding.