Showing papers on "Copper published in 1972"
Esso1
TL;DR: In this article, the effect of adding copper to nickel was investigated for the hydrogenolysis of ethane to methane and the dehydrogenation of cyclohexane to benzene over a series of copper-nickel alloys.
585 citations
TL;DR: In this article, the X-ray photoelectron spectra of some forty-six copper compounds and complexes have been measured and the chemical shifts obtained from accurate determinations of the binding energies have been qualitatively explained on the basis of the Pauling electronegativity concept using the group electrophoresis of Huheey for the polyatomic counter anions.
Abstract: The X-ray photoelectron spectra of some forty-six copper compounds and complexes have been measured. The chemical shifts obtained from accurate determinations of the binding energies have been qualitatively explained on the basis of the Pauling electronegativity concept using the group electronegatives of Huheey for the polyatomic counter anions. The chemical shifts of the copper atoms as well as the atoms in the ligands were found to be dependent not only on the oxidation state but also on the kind and number of ligand atoms. Intense satellite lines were found in the 2p and 2s bands of the cupric compounds; the number and splitting of the satellites were found to be sensitive to the chemical environment. A correlation was found between the satellite splitting and the binding energies and this is explained by a 3d→4s, 4p ‘shake-up’ mechanism.
447 citations
TL;DR: A series of alcohols and amines have been oxidised at oxide-covered nickel, silver, copper, and cobalt anodes in aqueous alkaline solutions as mentioned in this paper, and it was shown that the mechanism of these oxidations involves hydrogen abstraction from the substrate by an oxide species rather than direct electron transfer to the anode.
Abstract: A series of alcohols and amines have been oxidised at oxide-covered nickel, silver, copper, and cobalt anodes in aqueous alkaline solutions. The kinetics of these electrode processes have been studied and it is shown that the mechanism of these oxidations involves hydrogen abstraction from the substrate by an oxide species rather than direct electron transfer to the anode. The mechanism put forward is compared with those commonly suggested for the chemical reactions of transition-metal oxides and for heterogeneous catalysis.
313 citations
TL;DR: The increase in oxidation-reduction potential of the Type 1 copper and the two-electron acceptor in the presence of excess hexacyanoferrate seems to be due to a specific reduction of Type 2 copper by the hexacynoferrate (II).
271 citations
TL;DR: In this paper, X-ray photoelectron spectroscopy measurements of solid cuprous oxide have shown the presence of three kinds of oxygen species: O2, H2O, and O2-H2O.
218 citations
TL;DR: In this article, a cyclopentane-deuterium exchange has been followed on nickel and some nickel-copper alloys in the temperature range 200-430 °K.
175 citations
Patent•
20 Apr 1972TL;DR: In this paper, a method for direct bonding of metallic members to other metallic members with a metal-gas eutectic was described, which comprises placing a metal member such as copper in contact with another metal member, such as nickel, for example, heating the metal members to a temperature slightly below the melting point of the lower melting point metal, e.g., approximately 1,072*C.
Abstract: A method is described for direct bonding of metallic members to other metallic members with a metal-gas eutectic. The method comprises placing a metal member such as copper, for example, in contact with another metal member, such as nickel, for example, heating the metal members to a temperature slightly below the melting point of the lower melting point metal, e.g., approximately 1,072*C. for copper, the heating being performed in a reactive atmosphere, such as an oxidizing atmosphere, for a sufficient time to create a metal-gas eutectic melt which, upon cooling, bonds the metal members together. Various metals and reactive gases are described for direct bonding.
155 citations
152 citations
TL;DR: In this paper, the syntheses and properties of copper(II) and nickel (II) complexes of N,N′-alkylenebis(3-formyl-5-methylsalicylaldimine (alkylene=ethylene, propylene, or trimethylene) are described.
Abstract: The syntheses and properties of copper(II) and nickel(II) complexes of N,N′-alkylenebis(3-formyl-5-methylsalicylaldimine (alkylene=ethylene, propylene, or trimethylene) are described. By the reaction of these complexes with other alkylenediamines (ethylenediamine or trimethylenediamine), mononuclear copper(II) and nickel(II) complexes of new N4O2-type macrocycles have been synthesized. These complexes react with additional copper(II) or nickel(II) ions to form binuclear copper(II) or nickel(II) complexes. The geometries and properties of these new complexes are discussed.
146 citations
145 citations
TL;DR: In this article, the effect of sorbed molecules on the cation distribution was studied by adding ammonia, pyridine, naphthalene and butene to the dehydrated zeolite.
TL;DR: In this paper, a device for concentrating electropositive cations using porous, fixed, flow-through, carbon electrodes is described, and a preliminary economic analysis indicates that the value of copper recovered will more than pay for the installation and operation of the cell, even for fairly small units.
Abstract: A device for concentrating electropositive cations using porous, fixed, flow-through, carbon electrodes is described. A feed of 667μg of copper per ml of solution was reduced to less than 1μg of copper per ml of solution. The flow rate was 0.20 cm3/cm2/min through a bed 6 cm thick. Capital cost for the cell is the controlling factor. A preliminary economic analysis indicates that the value of copper recovered will more than pay for the installation and operation of the cell, even for fairly small units.
TL;DR: In this paper, the T 1 phase forms as extremely thin hexagonal-shaped plates with a {111} habit plane and nucleates either at GP zones or at dissociated dislocations by a stacking-fault mechanism.
Abstract: T 1 precipitation has been studied by electron microscopy in aluminium alloys containing (wt.-%) Cu 3.5, Li 1.5 and Cu 2.5, Li 2.0. The T 1 phase forms as extremely thin hexagonal-shaped plates with a {111} habit plane and, depending on the degree of super-saturation, nucleates either at GP zones or at dissociated dislocations by a stacking-fault mechanism. The precipitate is bounded by 1/6 Shockley partial dislocations and growth of the phase occurs by separation of these partial dislocations.
TL;DR: In this article, the concept of metal buffers and their use for calibration, testing and comparison of ion-selective electrodes is described and a series ofcopper(II) buffers has been prepared and used for intercomparison of a newly developed copper(II)-selectrode with corresponding Orion, Beckman and Radiometer solid-state membrane copper-II-selectively electrodes.
Patent•
21 Jan 1972
TL;DR: A bath for electrodepositing ductile, lustrous copper which comprises an aqueous acidic copper plating bath containing dissolved therein a brightening amount of the reaction product of polyethyleneimine and an alkylating agent which will alkylate the nitrogen of the polyethylenimine to produce a quaternary nitrogen as mentioned in this paper.
Abstract: A bath for electrodepositing ductile, lustrous copper which comprises an aqueous acidic copper plating bath containing dissolved therein a brightening amount of the reaction product of polyethyleneimine and an alkylating agent which will alkylate the nitrogen of the polyethyleneimine to produce a quaternary nitrogen, wherein the reaction temperature for the imine and alkylating agent ranges from about room temperature to about 120*C and the reaction product is present in the bath in an amount from about 0.1 to 1,000 milligrams per liter.
TL;DR: In this article, the electronic, e.s.r., and i.r. spectra of a series of polycrystalline Cu(dien)XY,zH2O and Cu(din)βX2 type complexes are reported.
Abstract: The electronic, e.s.r., and i.r. spectra of a series of polycrystalline Cu(dien)XY,zH2O and Cu(dien)βX2 type complexes are reported, where X and Y are various anions and β= ammonia, ethylenediamine, 2,2′-bipyridyl, and diethylenetriamine. From a correlation of the three types of spectral data a tentative prediction is made of the local molecular copper(II) ion environment present in the different complexes.
TL;DR: In this article, surface potentials, diffraction patterns, and vibrational frequencies have been compared in relation to the chemisorption bond and the relationship between the surface potential and the vibrational frequency has been discussed.
Abstract: Although it is much less active than the transition metals copper does catalyse reactions of hydrogen and carbon monoxide. The nature of the weak adsorptions of these gases has been investigated by surface potentials, low energy electron diffraction, and infrared spectroscopy. Hydrogen is dissociatively adsorbed by copper but the adsorption is activated. Surface potential measurements have provided isotherms and isosteric heats of adsorption. Carbon monoxide is adsorbed in two distinct stages giving positive and negative surface potential changes. The positive stage is accompanied by a sharp infrared absorption band near 2100 cm−1 which is sufficiently strong to permit reflection spectroscopic studies on single crystal surfaces. Frequency shifts occur during the negative stage. Direct comparisons of surface potentials, diffraction patterns, and vibrational frequencies have been made and will be discussed in relation to the chemisorption bond.
TL;DR: In this article, the LMM Auger spectrum from metallic copper has been studied in a high-resolution X-ray photoelectron spectrometer, and the agreement between experimental and calculated Auger electron energies is very good.
Patent•
20 Apr 1972TL;DR: In this paper, a method for direct bonding of metallic members to non-metallic members at elevated temperatures in a controlled reactive atmosphere without resorting to the use of electroless plating, vacuum deposition or intermediate metals is described.
Abstract: A method is described for direct bonding of metallic members to non-metallic members at elevated temperatures in a controlled reactive atmosphere without resorting to the use of electroless plating, vacuum deposition or intermediate metals. The method comprises placing a metal member such as copper, for example, in contact with a non-metallic substrate, such as alumina, heating the metal member and the substrate to a temperature slightly below the melting of the metal, e.g., between approximately 1,065*C. and 1,080*C. for copper, the heating being performed in a reactive atmosphere, such as an oxidizing atmosphere, for a sufficient time to create a copper-copper oxide eutectic melt which, upon cooling, bonds the copper to the substrate. Various metals, non-metals and reactive gases are described for direct bonding.
TL;DR: In this article, the potential dependence of reaction product composition has been studied on high purity binary Cu-Ni alloys (10 − 40%Ni) in 0·5M sodium chloride solution at 25°C.
TL;DR: In this paper, the stochastic and kinetics of the reaction between Grignard reagents and alkyl halides with a copper catalyst have been examined in tetrahydrofuran solutions.
TL;DR: In this paper, the structures of electroplated and vapordeposited copper films have been studied by x-ray diffraction, and it was shown that the electrical resistivity of these films is, at most, half of the grain-boundary resistivity.
Abstract: The structures of electroplated and vapor‐deposited copper films have been studied by x‐ray diffraction. While there was no evidence of stacking faults in any of these films, the electroplated films were characterized by presence of twins, large thickness‐dependent microstrains, and small particle sizes. The vapor‐deposited films, on the other hand, showed no twins, smaller microstrains, and large thickness‐dependent particle sizes. Analysis of the electrical resistivity of the electroplated films indicated that the twin resistivity of copper is, at most, half of the grain‐boundary resistivity.
TL;DR: In this article, total K-shell ionization cross sections by electron bombardment have been measured for copper silver and gold at various energies up to 140 keV, and total L III -shell ionisation cross sections for gold.
01 Dec 1972
TL;DR: The earliest copper alloy of the British Bronze Age is arsenical copper, a material relatively shortlived when compared with the succeeding tin bronze but of no little importance when tracing the stages and progress of prehistoric metal working as mentioned in this paper.
Abstract: The earliest copper alloy of the British Bronze Age is arsenical copper, a material relatively short-lived when compared with the succeeding tin bronze but of no little importance when tracing the stages and progress of prehistoric metal working. Like tin, arsenic functions as a mild deoxidant and confers the useful property of work-hardening upon the metal. Copper-arsenic alloys need to be strengthened by cold working, and it was probably this requirement as much as any other that would have led to their eventual disuse and replacement by cast tin bronzes. The normal source of arsenic for such alloys is generally agreed as a constituent of the copper ore actually smelted, usually the grey tetrahedrite tennantite mineral (Coghlan and Case, 1957; Tylecote, 1962), although other suggestions have been made (Charles, 1967).
TL;DR: In this paper, the valence bands of Cu, Ag and Ni have been obtained by X-ray photoemission spectroscopy (XPS) with a resolution of ≈ 0.5 eV.
TL;DR: The surface potentials (s.p.) of atomic hydrogen adsorbed at low temperature on clean copper films show wide variations from one film to another as discussed by the authors, which is believed to reflect varying proportions of different crystal planes.
Abstract: Surface potentials (s.p.) of atomic hydrogen adsorbed at low temperature on clean copper films show wide variations from one film to another. This is believed to reflect varying proportions of different crystal planes. Initial adsorption with a negative s.p. may be followed by a weaker adsorption with a positive effect. The negative s.p. corresponds to hydrogen which can be in equilibrium with gaseous molecular hydrogen. This spontaneous dissociative chemisorption has been studied between 242 and 337 K at pressures up to 60 Torr, using vibrating capacitor s.p. measurements to follow the equilibrium concentration of adatoms. Isosteric heats (typically 40–50 kJ mol–1) are almost independent of coverage on some films, and a major part of the adsorption can then be described approximately by the Langmuir isotherm for dissociative adsorption.
TL;DR: Toxicity of copper to T. pseudonana wax examined in inshore seawater using a 96‐hr bioassay method and population densities, mean cell, volume, and 14C bicarbonate uptake were measured.
Abstract: SUMMARY
Toxicity of copper to T. pseudonana (formerly Cyclotella nana, clone 13-1) wax examined in inshore seawater using a 96-hr bioassay method. Raw unenriched seawater wax filtered through a 0.22-μ membrane filter and then pasteurized, for 30 min at 60 C. Following this treatment, samples contained 0.68–1.14 μg Cu/liter. Copper was added as the chloride in 5-μg increments over the range of 5 to 30 μg/liter (about 0.1–0.5 μM). Population densities, mean cell, volume, and 14C bicarbonate uptake were measured.
Population growth, and 14C uptake by T. pseudonana displayed inhibition over the entire range of added copper. Growth rate constant (k) of T. pseudonana decreased with increasing copper concentration and during the course of growth at each concentration. Correspondingly, mean cell volumes increased with copper concentration and time. Copper toxicity varied in different water samples. The presence of decomposed natural plankton and detritus decreased toxicity. In the absence of enrichment, bacteria had little effect on copper toxicity. H exults were influenced by glassware treatment, collection and storage of seawater, and absence of enrichments.