Search results for "COPP"

Determination of antimony, arsenic, bismuth and copper by inductively coupled plasma atomic emission spectrometry in the electrorefining of copper

1996

Inductively coupled plasma atomic emissionspectrometry (ICP-AES) has been applied as a rapid and routine method for the analysis of process electrolytes in the electrorefining of copper. Antimony, arsenic, bismuth and copper have been selected as major electrolyte constituents. For these elements profound statistical studies of spectral and interelement effects have been carried out. For As, Bi and Sb two analyte wavelengths have been selected, and for Cu one relatively insensitive analyte line has been chosen due to the high Cu concentration in samples. Best analytical lines were: As at 193.759 nm, Bi at 306.772 nm, Sb at 206.833 nm and Cu at 216.953 nm. Multiple linear regression proved t…

Cyclam-functionalized silica-modified electrodes for selective determination of Cu(II)

2009

Cyclam derivatives have been grafted via 1, 2 or 4 silylated arms to the surface of mesoporous silica and the resulting materials have been incorporated into carbon paste electrodes and applied to the preconcentration electroanalysis of Cu(II). Sensitive and selective detection of the target analyte was achieved owing to the attractive binding properties of this macrocyclic ligand towards Cu(II) species. Various parameters likely to affect the preconcentration and detection steps have been studied, including pH of the accumulation medium, composition of the detection solution, structure and composition of the adsorbent, accumulation time, or presence of potentially interfering species. In p…

Optimization of operating conditions of axially and radially viewed plasmas for the determination of trace element concentrations from ultrasound-ass…

2006

Abstract The method of ultrasound-assisted extraction followed by inductively coupled plasma optical emission spectrometry (ICP-OES) used for the determination of trace element concentrations (arsenic, copper, lead, antimony, and zinc) in shooting range areas was optimized. Optimization was achieved not only on the basis of the analysis of appropriate standard reference materials but also on that of 31 synthetic mixtures of matrix and analyte elements (aluminum, antimony, arsenic, calcium, copper, lead, iron, manganese, silicon, and zinc), in five concentrations. All the measurements were performed in robust plasma conditions which were tested by measuring the Mg II 280.270 nm/Mg I 285.213 …

Combined Adsorption/Photocatalytic dye removal by copper-titania-fly ash composite

2020

Abstract Achieving both photocatalytic efficiency and adsorption capacity is essential to produce a highly efficient photocatalyst. This study fabricated a new photocatalyst by combining copper (Cu) doped titanium dioxide (TiO2) with fly ash (FA). The photocatalysts were synthesized using mild acid (acid-FA/Cu/TiO2), base (base-FA/Cu/TiO2), and deionized water (rFA/Cu/TiO2) activated FA. EDX confirmed the inclusion of Cu in both Cu/TiO2 and FA/Cu/TiO2 composites. XRD analysis indicated the presence of the anatase form of TiO2 after Cu doping and incorporation into modified FA. All three FA/Cu/TiO2 composites demonstrated high absorption (UV and visible region) compared to their TiO2 and Cu/…

Assessment of Copper Intake in Relation to Tolerable Upper Intake Levels

2018

Dynamic magnetic materials based on the cationic coordination polymer [Cu(btix)2]n(2n+) [btix = 1,4-bis(triazol-1-ylmethyl)benzene]: tuning the struc…

2012

A three-dimensional coordination polymer, [Cu(btix)(2)(BF(4))(2)](n) [btix = 1,4-bis(triazol-1-ylmethyl)benzene], with antiferromagnetic interactions occurring via the organic ligand, has been prepared and characterized. It has been shown to permit the exchange of anionic species in the crystalline network with modification of the magnetic properties. Coordinated BF(4)(-) can be reversibly exchanged by different anions with (NO(3)(-) and Cl(-)) or without (PF(6)(-) and ClO(4)(-)) dynamic response of the organic ligand, which acts as the only linker between the metal centers. Interestingly, an irreversible exchange occurs with N(3)(-) anions to generate a new coordination polymer, [Cu(btix)(…

Influence of the anions on the structure and magnetic properties of a series of bis(µ-diphexono)-bridged linear trinuclear copper(II) complexes: an e…

2011

The reaction of H(2)L (N,N'-dimethyl-N,N'-bis(2-hydroxy-3-methoxy-5-methylbenzyl)-ethylenediamine) with different copper salts, in methanol and using a H(2)L/Cu = 2 : 3 molar ratio, led to four new bis(μ-diphenoxo)-bridged Cu(3) complexes of general formula [{Cu(S)(μ-L)}(2)Cu(H(2)O)(2n)]X(2) (S = CH(3)OH, n = 1 and X = BF(4)(-) for (1) or ClO(4)(-) for (2); S = Br(3)(-) anion and n = 1 without any X species for (3); S = H(2)O, n = 0 and X = NO(3)(-) for (4)). The use in the same reaction conditions of 4,4'-bipyridine (4,4'-bipy) as connector led to the chain complex [{Cu(μ-4,4'-bipy)(0.5)(μ-L)}(2)Cu(H(2)O)(2n)](ClO(4))(2)·17H(2)O (5). The structure of the centrosymmetric trinuclear unit in …

"Reactivity of Cu3Si of different genesis towards copper(I) chloride"

2000

Abstract A comparative study of the reactivity between copper(I) chloride and three types of Cu 3 Si obtained in a molten medium (Cu 3 Si-Ref) and from mechanical activation following an annealing process (Cu 3 Si-M2AP) or a self-propagating high-temperature synthesis (Cu 3 Si-MASHS) was performed by thermogravimetry under vacuum using non-isothermal and isothermal methods of kinetic measurement. It was established that for the three Cu 3 Si/CuCl systems, the acceleration and decay stages in the temperature range 145–215°C are very closely approximated by an equation of the Prout–Tompkins type where an autocatalytic process was proposed. The lower apparent activation energy obtained for the…

3,4-Dihydro-2H-pyrrole-2-carbonitriles: Useful Intermediates in the Synthesis of Fused Pyrroles and 2,2′-Bipyrroles

2016

Various heterocyclic structures containing the pyrrole moiety have been synthesized from easily accessible 3,4-dihydro-2H-pyrrole-2-carbonitriles in one-pot procedures. 5,6,7,8-Tetrahydroindolizines, 2,3-dihydro-1H-pyrrolizines as well as 6,7,8,9-tetrahydro-5H-pyrrolo[1,2-a]azepines were obtained from these precursors in high yields in an alkylation/annulation sequence. The same conditions were applied in the synthesis of a 5,8-dihydroindolizine, which could easily be transformed to the corresponding indolizine by dehydrogenation. Furthermore, oxidative couplings of 3,4-dihydro-2H-pyrrole-2-carbonitriles with copper(II)-salts furnished 2,2'-bipyrroles as well as 5,5'-bis(5-cyano-1-pyrroline…

Interaction of metal ions with D-glucobenzothiazoline: isolation and characterization of the resultant products

2002

Six different metal-ion complexes of D-glucobenzothiazoline were synthesized and characterized by analytical and spectral techniques. Formation of different types of species (ML and ML2) were observed with Cu2+, Ag+, Cd2+, Hg2+, and Zn2+ ions. Existence of an anomeric mixture in the case of the Cu2+ complex is identified from the EPR spectra, and the results were further supported by the simulated spectra. The structures were proposed based on different studies.