Search results for "COPPER"
showing 10 items of 3029 documents
Spontaneous growth of 2D coordination polymers on functionalized ferromagnetic surfaces
2018
2D coordination polymers grow spontaneously on reactive surfaces due to surface oxidation. The growth process is observed in real time.
Toward the development of metal-based synthetic nucleases: DNA binding and oxidative DNA cleavage of a mixed copper(II) complex with N-(9H-purin-6-yl…
2009
Abstract The complex [Cu(N9-ABS)(phen) 2 ]·3.6H 2 O, H 2 N9-ABS = N -(9 H -purin-6-yl)benzenesulfonamide and phen = 1,10-phenanthroline, has been synthesized and then characterized with the aid of X-ray diffraction, analytical, and spectroscopic techniques. The geometry of Cu(II) is distorted square pyramidal with the equatorial positions occupied by three N atoms from two phenantroline molecules and one N atom from the adenine ring of the sulfonamide ligand. The interaction of the complex with DNA was studied by means of viscosity measurements and fluorescence spectroscopy. The results pointed to a classic intercalation of the complex between the DNA base pairs. The complex was found to b…
On the regeneration of thermally regenerative ammonia batteries
2018
In the past few years, thermally regenerative ammonia battery (TRAB) has been proposed as an effective tool to recover waste heat at temperatures below 130 °C. Most of the literature available is devoted to the power production step, with less attention being given to the regeneration step (e.g. the removal of ammonia from the anolyte). In this paper, the TRAB is analyzed with particular attention to the regeneration step and to the study of various generation of energy-regeneration cycles. It was shown that approximately 90 °C is necessary for the regeneration step due to the fact that ammonia is present in the anolyte mainly as a complex. Various cycles were performed with success, demons…
Avoidance of Cu- and Zn-contaminated soil by three ecologically different earthworm species
2005
Earthworm avoidance response to soils contaminated with harmful substances has been proposed as a potential tool for assessing soil toxicity with low test effort. In the present study, the objective was to find out whether three ecologically different earthworm species, Aporrectodea tuberculata (Eisen), Lumbricus rubellus (Hoffmeister), and Dendrobaena octaedra (Savigny), avoid soils simultaneously spiked with Cu and Zn. In addition, metal-contaminated field soil taken close to a Cu-Ni smelter was tested with A. tuberculata using a two-section avoidance lest procedure. All three earthworm species clearly avoided Cu/Zn contaminated soil but differently: D. octaedra was the most sensitive spe…
Silver(I), Copper(I) and Copper(II) Complex of the New N,Se-Chelate Ligand 2-Phenylselenomethyl-1H-benzimidazole: Electrochemistry and Structure
2009
Abstract. 2-Phenylselenomethyl-1H-benzimidazole (psbi) can form complexes in 2:1 ratio with coinage metal ions. Crystal structure analysis revealed a flattened metal coordination for [AgI(psbi)2](BF4) (1), approaching a distorted planar arrangement with weak Ag-Se bonds (d > 2.9 A) and confirmed as energy minimum by DFT calculations. The typical Jahn-Teller system [CuII(psbi)2Cl2] (2) exhibits a planar CuN2Cl2 core with weak Se---Cu---Se axial ligation (3.2944(8) A Cu--Se distance). The oxygen-sensitive compound [CuI(psbi)2](BF4) (3) exhibits electrochemically reversible oxidation in contrast to the silver(I) analogue 1.
Unique Bridging Function of the Triazole Core in Copper(II) Chloride Complexes with 1-Allylbenzotriazole
2005
During alternating-current electrochemical synthesis of copper(I) π-complex of [CuCl{C6H4N3(C3H5)}] composition, starting from ethanol solution, containing CuCl2·2H2O and 1-allylbenzotriazole, green crystals of intermediate [CuII3Cl6{C6H4N3(C3H5)}4] (I) compound has been obtained upon 24 h. After some days these crystals transform into red ones of [CuII2Cl4{C6H4N3(C3H5)}3] (II). Both compounds were X-Ray structurally investigated. Crystals of I are triclinic, sp.gr. a = 9.1329(9), b = 10.0352(4), c = 12.239(3) A, α = 76.443(13), β = 84.470(14), γ = 76.808(7)°, V = 1060.5(3) A3, R = 0.0414 for 3311 reflections. II: monoclinic, C2/c, a = 13.828(1), b = 15.044(2), c = 10.702(1) A, β = 91.36(1)…
Inhibitoren der Korrosion 30 (1,2) - Vergleichende Studien über das Verhalten bekannter und bisher unbekannter Inhibitoren der Korrosion des Kupfers …
1985
Folgende Verbindungen wurden auf ihre Fahigkeit zur Inhibierung der Korrosion von Kupferproben unter Standardbedingungen uberpruft: Benzotriazol (BTA), 5-Aminotetrazol-monohydrat (5-AT), 2,5-Diphenyl-3-(m-chlorphenyl)-tetrazolium-nitrat (Tetrazin-B), α- und β-Naphthylamin, Phenylthioharnstoff, Xanthanwasserstoff, 2-Mercaptothiazolin (2-MT) und Kupferron. Folgende Messungen wurden durchgefuhrt: Bestimmung der Geschwindigkeit der Sauerstoffaufnahme im Schuttelversuch und pH-statische Verfolgung des Korrosionsverlaufs in Abhangigkeit (a) von der Konzentration des Inhibitors, (b) dem Verteilungszustand der Kupferprobe (Korn, Staub, Blech), (c) der Anwesenheit von Cu2+-Ionen und (d) dem pH-Wert.…
Cu2+and AMP complexation of enlarged tripodal polyamines
2006
The synthesis, characterization, Cu2+ coordination and interaction with AMP of three tripodal polyamines are reported. The polyamines are based on the structure of the tetraamine (tren) which has been enlarged with three propylamino functionalities (TAL), with a further anthrylmethyl fragment at one of its terminal primary nitrogens (ATAL) or with naphthylmethyl fragments at its three ends (N3TAL). The protonation constants of all three polyamines show that at pH 6, all six primary and secondary nitrogen atoms in the arms are protonated. The interaction with Cu2+ and AMP (adenosine-5′-monophosphate) has been studied by potentiometric, UV-Vis, ESI-MS spectroscopy and NMR techniques. pH-Metri…
Metallosupramolecular compounds based on Cu(ii)/oxalate/twisted NSSN ligands showing a new in situ S–C bond cleavage
2013
Four new complexes, [Cu2(C2O4) 2(SCS)]·3H2O (1), [Cu2(C 2O4)3(SCSH)2]·H2O (2), [Cu(C2O4)(SS)2]·3H2O (3) and [Cu(C2O4)(SS)]·6H2O (4) [where SCS = bis(4-pyridylthio)methane and SS = 4,4′-dipyridyldisulfide], have been synthesized by the reaction of the SS and SCS ligands with the corresponding copper(ii) oxalate salt. The different synthetic conditions allowed control of the preparation of a 3D open metal-organic framework in 1, a dinuclear zwitterionic molecular compound in 2 and one- and two-dimensional (1D and 2D) coordination polymers in 3 and 4, respectively. Compound 4 was also obtained by in situ transformation of the dithioether ligand (SCS) to the disulfide ligand (SS) under hydrothe…
Synthesis and Characterization of a Stable Copper(I) Complex for Radiopharmaceutical Applications
2014
A highly stable copper(I) complex was obtained starting from a copper(II) salt. This compound was characterized by a combination of several analytical techniques (UV/Vis spectroscopy, energy-dispersive X-ray spectroscopy, electrochemistry, and X-ray photoelectron spectroscopy) and was shown to present an N4Cu structure. These results were confirmed by a density functional calculations study of the binding energy and the electronic structure of model ligand and copper complexes. Preliminary tests of complexation showed a high ability of the corresponding ligand to chelate 64Cu in very diluted medium, which is of interest for developing new positron emission tomography imaging agents. The sta…