Search Results
2-hydroxyethylammonium iodide
2014, Kohrt, C., Spannenberg, A., Werner, T.
In the crystal structure of the title salt, C2H 8NO+·I-, N-H⋯O, N-H⋯I and O-H⋯I hydrogen bonds lead to the formation of layers staggered along the c axis.
Towards on-site testing of Phytophthora species
2014, Schwenkbier, Lydia, Pollok, Sibyll, König, Stephan, Urban, Matthias, Werres, Sabine, Cialla-May, Dana, Weber, Karina, Popp, Jürgen
Rapid detection and accurate identification of plant pathogens in the field is an ongoing challenge. In this study, we report for the first time on the development of a helicase-dependent isothermal amplification (HDA) in combination with on-chip hybridization for the detection of selected Phytophthora species. The HDA approach allows efficient amplification of the yeast GTP-binding protein (Ypt1) target gene region at one constant temperature in a miniaturized heating device. The assay's specificity was determined by on-chip DNA hybridization and subsequent silver nanoparticle deposition. The silver deposits serve as stable endpoint signals that enable the visual as well as the electrical readout. Our promising results point to the direction of a near future on-site application of the combined techniques for a reliable detection of Phytophthora species.
(η6-Benzene)dichlorido(chlorodicyclohexylphosphane-κp) ruthenium(II) chloroform monosolvate
2014, Gowrisankar, S., Neumann, H., Spannenberg, A., Beller, M.
The title compound, [RuN4(-6-C6H6) (C12H22ClP)]-CHCl3, was prepared by reaction of [RuN 4(-6-C6H6)]2 with chlorodicyclohexyl phosphane in CHCl3 at 323 K under argon. The RuII atom is surrounded by one arene ligand, two Cl atoms and a phosphane ligand in a piano-stool geometry. The phosphane ligand is linked by the P atom, with an Ru-P bond length of 2.3247 (4) Å. Both cyclohexyl rings at the P atom adopt a chair conformation. In the crystal, the RuII complex molecule and the chloroform solvent molecule are linked by a bifurcated C-H⋯(Cl,Cl) hydrogen bond. Intramolecular C-H⋯Cl hydrogen bonds are also observed.
Determining surface structure and stability of ε-Fe2C, χ-Fe5C2, θ-Fe3C and Fe4C phases under carburization environment from combined DFT and atomistic thermodynamic studies
2014, Zhao, Shu, Liu, Xing-Wu, Huo, Chun-Fang, Li, Yong-Wang, Wang, Jianguo, Jiao, Haijun
The chemical–physical environment around iron based FTS catalysts under working conditions is used to estimate the influences of carbon containing gases on the surface structures and stability of ε-Fe2C, χ-Fe5C2, θ-Fe3C and Fe4C from combined density functional theory and atomistic–thermodynamic studies. Higher carbon content gas has higher carburization ability; while higher temperature and lower pressure as well as higher H2/CO ratio can suppress carburization ability. Under wide ranging gas environment, ε-Fe2C, χ-Fe5C2 and θ-Fe3C have different morphologies, and the most stable non-stoichiometric termination changes from carbon-poor to carbon-rich (varying surface Fe/C ratio) upon the increase in ΔμC. The most stable surfaces of these carbides have similar surface bonding pattern, and their surface properties are related to some common phenomena of iron based catalysts. For these facets, χ-Fe5C2-(100)-2.25 is most favored for CO adsorption and CH4 formation, followed by θ-Fe3C-(010)-2.33, ε-Fe2C-(121)-2.00 and Fe4C-(100)-3.00, in line with surface work function and the charge of the surface carbon atoms.
(Cyanido-κC)(2,2-diphenylacetamido-κ2 N,O)bis(η5-pentamethylcyclopentadienyl)zirconium(IV)
2014, Becker, L., Spannenberg, A., Arndt, P., Rosenthal, U.
In the title compound, [Zr(C10H15)2(C14H12NO)(CN)], the ZrIV atom is coordinated by two pentamethylcyclopentadienyl ligands, the amidate ligand via the N and O atoms, and an additional C N ligand. The four-membered metallacycle is nearly planar (r.m.s. deviation = 0.008Å). In the crystal, the molecules are connected into centrosymmetric dimers via pairs of N - HN hydrogen bonds.
(η6-Benzene)(carbonato-κ2O,O') [dicyclohexyl(naphthalen-1-ylmethyl)phosphanejP] ruthenium(II) chloroform trisolvate
2014, Gowrisankar, S., Neumann, H., Spannenberg, A., Beller, M.
The title compound, [Ru(CO3)(η6-C 6H6){(C6H11)2P(CH 2-C10H7)}]-3CHCl3, was synthesized by carbonation of [RuCl2-(η6-C6H 6){(C6H11)2P(CH2C 10H7)}] with NaHCO3in methanol at room temperature. The RuIIatom is surrounded by a benzene ligand, a chelating carbonate group and a phosphane ligand in a piano-stool configuration. The crystal packing is consolidated by C-H⋯O and C-H⋯Cl hydrogen-bonding interactions between adjacent metal complexes and between the complexes and the solvent molecules. The asymmetric unit contains one metal complex and three chloroform solvent molecules of which only one was modelled. The estimated diffraction contributions of the other two strongly disordered chloroform solvent molecules were substracted from the observed diffraction data using the SQUEEZE procedure in PLATON.
Modified bibenzimidazole ligands as spectator ligands in photoactive molecular functional Ru-polypyridine units? Implications from spectroscopy
2014, Meyer-Ilse, J., Bauroth, S., Bräutigam, M., Schmitt, M., Popp, J., Beckert, R., Rockstroh, N., Pilz, T.D., Monczak, K., Heinemann, F.W., Rau, S., Dietzek, B.
The photophysical properties of Ruthenium-bipyridine complexes bearing a bibenzimidazole ligand were investigated. The nitrogens on the bibenzimidazole-ligand were protected, by adding either a phenylene group or a 1,2-ethandiyl group, to remove the photophysical dependence of the complex on the protonation state of the bibenzimidazole ligand. This protection results in the bibenzimidazole ligand contributing to the MLCT transition, which is experimentally evidenced by (resonance) Raman scattering in concert with DFT calculations for a detailed mode assignment in the (resonance) Raman spectra.
The use of matrix-specific calibrations for oxygen in analytical glow discharge spectrometry
2014, Gonzalez-Gago, C., Smid, P., Hofmann, T., Venzago, C., Hoffmann, V., Gruner, W.
The performance of glow discharge optical emission spectroscopy and mass spectrometry for oxygen determination is investigated using a set of new conductive samples containing oxygen in the percent range in three different matrices (Al, Mg, and Cu) prepared by a sintering process. The sputtering rate corrected calibrations obtained at standard conditions for the 4 mm anode (700 V, 20 mA) in GD-OES are matrix independent for Mg and Al but not for Cu. The importance of a "blue shifted" line of oxygen at 130.22 nm (first reported by Köster) for quantitative analyses by GD-OES is confirmed. Matrix-specific calibrations for oxygen in GD-MS are presented. Two source concepts - fast flow (ELEMENT GD) and low gas flow (VG9000) - are evaluated obtaining higher sensitivity with the static flow source. Additional experiments using Ar-He mixtures or μs pulsed GD are carried out in ELEMENT GD aiming to improve the oxygen sensitivity.
Bis(μ2-isopropylimido-κ2 N:N)bis[(η5-cyclopentadienyl)(ethenolato-κO)titanium(IV)]
2014, Haehnel, M., Spannenberg, A., Rosenthal, U.
The title dinuclear half-sandwich complex, [CpTi(OCH=CH2) (μ2-N-iPr)]2 (Cp = cyclopentadienyl; iPr = isopropyl), was obtained from the reaction of Cp2TiCl2, n-butyllithium and isopropylamine in tetrahydrofuran. Each TiIV atom is coordinated by one Cp ligand, one vinyloxy unit and two bridging imido groups in a strongly distorted tetrahedral geometry. There are two half molecules in the asymmetric unit, such that whole molecules being generated by inversion symmetry.
The effect of supported MoOX structures on the reaction pathways of propene formation in the metathesis of ethylene and 2-butene
2014, Hahn, T., Kondratenko, E.V., Linke, D.
The kind of surface MoOX structures on Al2O3–SiO2 was found to determine propene selectivity in the metathesis of ethylene and 2-butene. Compared to isolated tetrahedral MoOX species, their polymerized octahedral counterparts show significantly lower activity for isomerisation of 2- to 1-butene thus hindering non-selective metathesis of these butenes. In addition, they reveal higher ability to engage ethylene in propene formation.