Search results for "copper"

Insight into the mechanism of diazocompounds transformation catalyzed by hetero cuboidal clusters [Mo3CuQ4(MeBPE)3X4]+, (Q=S, Se; X=Cl, Br): The cata…

2008

Abstract Two enantiomerically pure trinuclear compounds of formula (P)-[Mo3S4{(R,R)-Me–BPE}3Br3]Br and (P)-[Mo3Se4{(R,R)-Me–BPE}3Cl3]Cl, (P)-1b.Br and (P)-1c.Cl, respectively, have been synthesized in a good yield and a stereospecific manner by excision of polymeric [Mo3Q7X4]n (Q = S or Se, X = Cl or Br) phases with (R,R)-Me–BPE{1,2-bis[(2R,5R)-2,5-(dimethylphospholan-1-yl)]ethane}. They have been transformed into chiral hetereo cuboidal compounds [Mo3S4{(R,R)-Me–BPE}3Br3]PF6, (P)-2b.PF6, and [Mo3Se4{(R,R)-Me–BPE}3Cl3]PF6, (P)-2c.PF6, by reaction with copper salts. All these compounds have been characterized by 31P NMR, IR, UV–Vis, mass spectrometry, elemental analysis, and chiral dichroism…

Towards controlling PCDD/F production in a multi-fuel fired BFB boiler using two sulfur addition strategies. Part II: Thermodynamic analysis

2014

Abstract A staged equilibrium process model was developed for a bubbling fluidized bed boiler firing SRF, bark and sludge. The model was used to study the influence of sulfur addition strategies (S-pellet additive and peat co-firing) on the behavior of copper, bromine, and alkalis. Aerosol samples collected from the backpass of the boiler were used to validate the chemistry predicted by the model. The model revealed that Cu existed as Cu 2 S (s3) in the reducing zone, and CuCl (g) (for all test cases) and CuO (s) (during peat co-firing) in the oxidation zones. CuBr 3(g) was also present after the introduction of tertiary air. However the model failed to predict the formation of CuSO 4 , an …

Copper(II) complexes with the N,N,O-tridentate ligand 6-amino-5-formyl-1,3-dimethyluracilato-(N6)-benzoylhydrazone: synthesis, spectral and XRD studi…

1999

Abstract From reactions between different Cu(II) salts and the Schiff base 6-amino-5-formyl-1,3-dimethyluracil-benzoylhydrazone (H2BEZDO) in alcohol, six new copper complexes with simplified formulas [Cu(HBEZDO)(H2O)(MeOH)]NO3 (1), [CuCl(HBEZDO)(DMF)] (2), [CuBr(HBEZDO)]·2H2O (3), CuBr(HBEZDO) (4), Cu(ClO4)(HBEZDO)·H2O (5), and Cu(SO4)1/2(HBEZDO)·1 1 2 H2O (6) were isolated. The structures of compounds 1, 2 and 3 have been established by means of XRD diffraction methods. In the three compounds, the Schiff base acts as a tridentate monodeprotonated ligand through the N(6), N(51) and O(52) atoms, making two five- and six-membered chelate rings. In the structure of 1 and 2, the solvent molecul…

Territories, identities and strategies in Forez from the sixth at the first front millenium BC in the upstream basin of the Loire (France)

2007

This thesis heading Territories, identities and strategies in Forez from the sixth at the first front millenium BC in the upstream basin of the Loire, relates to an extent in the north-Eastern part of the Massif central in contact with the Rhodanian corridor. This intramontane sector (current department of Loire 42) has allowed to build a consequent archaeological corpus which clarified behaviors having strong socio-economic and environmental implications. The archaeological study called upon various disciplines: agronomy, anthropology, archeometry (palynology, dating 14C, etc.), ceramology, geography, geomorphology, petrography, sedimentology, volumetry. It recuts several sets of themes : …

Multiple-scan voltammetry and OCP: Archaeometric tools for dating archaeological bronzes

2021

[EN] The application of a multiple-scan strategy to nanosamples taken from 18 cross-sections of Bronze Age arms and armour, as well as two Roman coins using two solid-state electrochemical techniques, the voltammetry of immobilized microparticles (VIMP) and open circuit potential measurements (OCP) is described. The voltammetric responses in contact with aqueous acetate buffer can be attributed to the reduction of cuprite with variable degree of compaction and crystallinity revealing significant differences in the gradient of such properties with depth. Such differences are also revealed by "dry" OCP measurements connecting points in the cross section near and separated from the corrosion l…

"Résumé de thèse, Le Forez du VIe au Ier millénaire av. J.-C. Territoires, identités et stratégies des sociétés humaines du Massif central dans le ba…

2009

Summary of thesis: Forez from the sixth to the first front millennium BC, Territories, identities and strategies of human societies in the upstream basin of the Loire (France) by Vincent GEORGES defended on 20th December 2007 at the University of Bourgogne; Joëlle Burnouf (reporter), Hervé Cubizolle (co-dir.), José Gomez de Soto (chair), Vincent Guichard (exam.), Claude Mordant (dir.), Pierre Pétrequin (reporter). This thesis is available online on www.tel.archives-ouvertes.fr.

New perspectives on the human occupation of the Gulf of Palermo during the Metal Ages: the funerary cave of Zubbio di Cozzo San Pietro (Bagheria) and…

2020

Abstract The Archaeological Superintendency of Palermo (Sicily), with the chair of Anthropology at the University of Palermo, carried out a preliminary investigation in the Zubbio of Cozzo San Pietro (Bagheria) – a cave known so far only from a speleological point of view - which proved to be a funerary cave dating to the Copper/Bronze Age. In the course of archaeological work during the installation of the electricity grid in the Mondello area (Palermo), part of a necropolis consisting of three oven-shaped tombs was exposed. The tombs multiple depositions, whose remains were found in a very bad state of preservation. Based on the type of funerary structures and the equipment found in them,…

Pressure-induced chemical decomposition of copper orthovanadate (α-Cu3V2O8)

2021

The high pressure stability of α-Cu3V2O8 has been investigated via complementary high pressure synchrotron X-ray diffraction experiments and theoretical density functional theory calculations. The results of both experiment and theory are in close agreement. The main result of this work is that α-Cu3V2O8 undergoes a pressure-induced chemical decomposition into CuO and V2O5 at a modest pressure of ∼1.35 GPa according to the experimental observations, and at ∼2.45 GPa according to the calculations. The decomposition is investigated with enthalpy calculations and one of the main driving factors is the stability of the octhedral oxygen-coordination of the metal atoms in the decompositon product…

Copper quality and provenance in Middle Bronze Age I Byblos and Tell Arqa (Lebanon)

2013

Shrinkage Bubbles: The C–O–H–S Magmatic Fluid System at San Cristóbal Volcano

2018

New analytical results for the composition of shrinkage bubbles (09-70 vol. %) in olivine-hosted (Fo <80%) primary melt inclusions (MIs) have been incorporated into a novel geochemical model for San Cristó bal volcano, Nicaragua. The vapour, liquid, and mineral components found inside shrinkage bubbles may represent relics of early C-O-H-S fluids exsolved from a magmatichydrothermal system. This conclusion is supported by high-resolution Raman microspectroscopy revealing: (1) gaseous CO2 (d=0·17-0·31 g/cm3 in 31 samples) coexisting with liquid H2O (in seven samples) at ambient temperature (<22°C) inside the shrinkage bubbles of naturally quenched inclusions; (2) several mineral phases (i.e.…