Scopus İndeksli Yayınlar Koleksiyonu / Scopus Indexed Publications Collection
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Article Citation - WoS: 1Citation - Scopus: 1Hydrothermal 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, MehtapTwo 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: 19Citation - Scopus: 21Synthesis and Additive Manufacturing of Calcium Silicate Hydrate Scaffolds(Elsevier, 2021) Oğur, Ezgi; Botti, Renata; Bortolotti, Mauro; Colombo, Paolo; Ahmetoğlu, Çekdar VakıfA 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: 7Citation - Scopus: 7Hydrothermal 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: 5Citation - Scopus: 5Hydrothermal 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: 4Citation - Scopus: 4Hydrothermal Synthesis and Characterization of a Novel Supramolecular Hybrid Based on Keggin and Cu(i) Complex(Elsevier, 2013) Eanes, Mehtap; Önen, BanuA 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.