Main Group Chemistry - Volume 16, issue 4

Authors: Kunt, Kubra | Dur, Fatma | Yildirim, Meral | Derun, Emek Moroydor

Article Type: Research Article

Abstract: In this study, the influences of air-entraining, set accelerating and superplasticizer admixtures on the properties of borogypsum containing cement mortars were investigated. According to results, by using 3% borogypsum and water/binder ratio of 0.45, the compressive and flexural strength values were increased up to 196.38%. The usage of various ratios of air-entraining and set accelerating admixtures showed reverse effects on the compressive and flexural strength. However, 0.4% superplasticizer containing mortars had 65.39 MPa compressive strength and 9.08 MPa flexural strength which were 33.12% and 26.82% higher than the reference. Durability test results showed addition 3% borogypsum provided endurance to sulfate attacks up …to 30 days. Show more

Keywords: Borogypsum, chemical admixtures, durability, mortar

DOI: 10.3233/MGC-170239

Citation: Main Group Chemistry, vol. 16, no. 4, pp. 227-239, 2017

Authors: Drisya, R. | Soumya Mol, U.S. | Satheesh Chandran, P.R. | Simi, C.K. | Sudarsanakumar, M.R. | Sudhadevi Antharjanam, P.K.

Article Type: Research Article

Abstract: A 2D barium complex formulated as [Ba(C6 H4 NO3 )(Cl)(H2 O)]n was successfully synthesized by gel diffusion technique using hydrosilica gel medium at room temperature. Single crystal X-ray diffraction studies confirm that the complex is triclinic with space group P 1 ¯ and exhibits a 2D framework by the interconnection of oxobridge and chlorobridge in alternative layers. The unit cell dimensions are a  = 5.7737(2) Å, b  = 6.8503(2) Å, c  = 11.5378(4) Å, α= 106.432(2)°, β= 100.644(2)°, γ= 93.049(2)°. The crystal structure is further stabilized by a 3D one through a pair of N–H ⋯O intermolecular hydrogen …bonds to form R2 2 (8) ring motifs. Each barium cation is nine coordinated to form distorted tricapped trigonal prism geometry. The gel grown crystals were characterized by several physico-chemical techniques including elemental analysis, FT-IR, UV-Visible spectral studies, powder X-ray diffraction and thermogravimetry. Show more

Keywords: Gel diffusion technique, single crystal X-ray diffraction, 2D framework, 2-hydroxynicotinic acid

DOI: 10.3233/MGC-170240

Citation: Main Group Chemistry, vol. 16, no. 4, pp. 241-254, 2017

Authors: Demirhan, Nebahat | Peksel, Ayşegül | Elmali, Fikriye Tuncel | Eren, Mürfe

Article Type: Research Article

Abstract: A new Long-chain, di-Schiff base ligand (N2 O2 donor, L) has been synthesized by the reaction of dodecylamine with, 1,5-bis(2’-formylphenyl)-1,5-dioxapentane in molar, 2:1 ratio (yielded 82%) and its Ru(II) complex have been prepared (yielded 78%) in solvent-free conditions. The newly synthesized compounds have been verified by ATR-IR, UV-vis., mass (LC-MS and MALDI-TOF) and NMR (1 H,13 C) spectra, elemental and thermal analysis. The DNA binding studies of the ligand and complex were examined by absorption method. The results indicated that the ligand and Ru(II) complex could interact with calf thymus DNA (CT-DNA) through electrostatic or/and groove binding (minor/major). The …apparent binding constant values (Kb ) of the ligand and Ru(II) complex at room temperature were calculated to be 5.9×105 M-1 and 7.9×105 M-1 , respectively. Antioxidant study of the ligand and complex showed significant antioxidant activity against lipid peroxidation. The ligand and complex also have moderate radical scavenging properties. Show more

Keywords: Di-Schiff base, solvent-free reactions, antioxidative activities, DNA binding

DOI: 10.3233/MGC-170241

Citation: Main Group Chemistry, vol. 16, no. 4, pp. 255-266, 2017

Authors: Zhang, Wei-na | Hai, Shi-kun | Li, Chun-ling | Wang, Nai-ping | Shao, Jing | Zhang, Zhan | Ye, Bao-xian

Article Type: Research Article

Abstract: The precursors of SnO2 nanoparticles at different temperatures were synthesized by hydro-thermal method, and then SnO2 nanoparticles were obtained by calcination in this paper. Then the structure and micromorphology were characterized by X-ray Diffraction (XRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM), and the chemical composition of the products were analyzed by infrared spectroscopy (IR) and ultraviolet visible diffuse reflectance spectroscopy (UV-vis DRS), finally, the photocatalytic degradation ability of prepared products were studied by ultraviolet absorption method. The results showed that the low temperature reaction is beneficial to the formation of particle products, and the calcined …products were pure stannic oxide particles with rutile structure, which had good crystallinity, good dispersibility, uniform size and strong photocatalytic degradation ability. Show more

Keywords: Stannic oxide, nanoparticle, hydro-thermal method, photocatalysis

DOI: 10.3233/MGC-170242

Citation: Main Group Chemistry, vol. 16, no. 4, pp. 267-274, 2017

Authors: Liang, Li | Shaomin, Lei | Min, Hu | Huihua, Luo | Teng, Huang

Article Type: Research Article

Abstract: To increase the production of potash, it is important to convert insoluble potassium-rich minerals into soluble potash salt efficiently. This paper focused on the extraction of soluble potassium from potassium feldspar with normal pressure and negative pressure in the reaction system of hydrofluoric acid–sulfuric acid. The mineralogy of the crude potassium feldspar was studied by X-Ray Fluorescence (XRF) and X-ray Diffraction (XRD) analyses. Factors of ammonium fluoride dosage, reaction time and system pressure on extraction efficiency of soluble potassium were investigated and system pressure is emphasized. The results shows that the dissolution rate of potassium was 79.3 wt.% with 0.5 g·g–1 …ammonium fluoride for 2 h at atmospheric pressure. The dissolution rate was 93.1 wt.% at combined normal pressure for 1.5 h with negative pressure (–0.06 Mpa) for 0.5 h, which increased 13.87 wt.% for the extraction efficiency of soluble potassium. The dissolution mechanism was revealed by the thermodynamics calculation of potassium feldspar and demonstrated by phase identification and morphology of extraction residue using XRD. The process is novel method to extracted a large amount of soluble potassium from potassium feldspar which belongs to a simple, economical and effective chemical extraction method. Show more

Keywords: Potassium feldspar, dissolution, extracting potassium, negative pressure

DOI: 10.3233/MGC-170243

Citation: Main Group Chemistry, vol. 16, no. 4, pp. 275-289, 2017

Authors: Soumya Mol, U.S. | Drisya, R. | Satheesh Chandran, P.R. | Sudarsanakumar, M.R. | Prathapachandra Kurup, M.R.

Article Type: Research Article

Abstract: Metal carboxylates possess wide range of intriguing structural topologies due to their diverse ligational behavior of carboxylate group. Two new polymorphs of monomeric complex, [Ca(dga)(H2 O)5 ].H2 O (1 ) and the three-dimensional metal-organic framework, [Ba(dga)(H2 O)] (2 ) (dgaH2  = diglycolic acid) have been grown by gel diffusion technique at room temperature. Colourless transparent crystals were obtained within one week. Single crystal X-ray diffraction study reveals that the title compounds crystallized in monoclinic P21 /n in 1 and orthorhombic system with space group Pnma in 2 . The monomeric units, CaO8 interact each other via extensive hydrogen bonding …among the coordinated and the lattice water molecules with the carboxylate oxygen atoms to form a 2D supramolecular sheet like structure in 1 . The adjacent BaO8 polyhedra are connected by diglycolate ligand forming the 3D framework with porous architecture in 2 . Elemental analysis, FT-IR, UV-Visible, thermogravimetric, powder X-ray diffraction and solid state photoluminescence studies were also carried out. Show more

Keywords: Crystal structure, gel diffusion technique, single crystal X-ray diffraction, 3D and 2D structure, photoluminescence

DOI: 10.3233/MGC-170244

Citation: Main Group Chemistry, vol. 16, no. 4, pp. 291-305, 2017

Authors: Bruggen, Jessica A. | Feller, Keyton D. | Schickel, Henry I. | Tuleushova, Nazym | Zhukush, Medet | Lam, Kevin | Barry, Brian M. | Kemp, Richard A.

Article Type: Research Article

Abstract: A series of Group 13 complexes MLX2 (M = Al or Ga, L = SC6 H4 -2-Pt Bu2 or OC6 H4 -2-Pt Bu2 , X = Me or C6 F5 ) have been synthesized and characterized by multinuclear NMR spectroscopy and single crystal X-ray diffraction. Reactions of Me3 Al or Me3 Ga with an equivalent of either 2-t Bu2 P(C6 H4 )OH (1 ) or 2-t Bu2 P(C6 H4 )SH (5 ) resulted in the formation of four new (2 ,3 ,6, and 7 ), 4-coordinate dimethyl chelate (S,P or O,P) complexes via methane elimination. …The dimethyl gallium complexes (3 and 7 ) underwent a further reaction with excess B(C6 F5 )3 , and through ligand exchange (methyl/pentafluorophenyl), resulted in the disubstituted bis(pentafluorophenyl) analogs (4 and 8 ). Cyclic voltammetry (CV) experiments for all compounds in the presence of and the absence of (1 –8 ) CO2 were performed. For compounds showing cathodic reduction waves under CO2 (2 ,3 ,4 , and 6 ), bulk electrolysis experiments were performed. Electrochemical studies indicate that, for several compounds, a transient CO2 adduct is formed which undergoes a one-electron, irreversible (or partially irreversible) reduction to form an unstable radical anion. Show more

Keywords: Carbon dioxide, main-group complex, cyclic voltammetry, X-ray crystallography, phosphinophenolate, phosphinobenzenethiolate, frustrated Lewis pair

DOI: 10.3233/MGC-170245

Citation: Main Group Chemistry, vol. 16, no. 4, pp. 307-319, 2017