scispace - formally typeset
Search or ask a question

Showing papers on "Cobalt published in 1982"


Journal ArticleDOI
TL;DR: In this paper, the feasibility of using XPS to characterize the different Co-containing phases which may be present in sulfided Co-Mo catalysts was examined, and it was shown that by a combination of accurate determinations of binding energy differences and comparisons of peak shapes it is possible to distinguish the different CO phases in the catalysts by XPS.

313 citations


Journal ArticleDOI
TL;DR: In this paper, preliminary results on cobalt-containing heterogeneous catalysts for the selective synthesis of C1-C6 alcohols from carbon monoxide and hydrogen are presented.

246 citations


Journal ArticleDOI
TL;DR: The corrosion rates of chromium and nickel showed a slight increase, while cobalt and copper dissolved to a very much greater extent in the presence of protein, however, with molybdenum the corrosion was inhibited by protein.
Abstract: The corrosion of the pure metals aluminium, cobalt, copper, chromium, molybdenum, nickel, and titanium and of a cobalt-chromium molybdenum casting alloy has been studied in buffered saline with and without the presence of the proteins serum albumin and fibrinogen. The corrosion of aluminium and titanium was unaffected by the protein. The corrosion rates of chromium and nickel showed a slight increase, while cobalt and copper dissolved to a very much greater extent in the presence of protein. However, with molybdenum the corrosion was inhibited by protein.

238 citations


Book ChapterDOI
01 Jan 1982
TL;DR: In this paper, the spectral and magnetic properties of simple high spin cobalt(II) complexes are reviewed with the aim of showing how it is possible to relate the experimental data to the electronic structure and the coordination geometry of the complexes.
Abstract: The spectral and magnetic properties of simple high spin cobalt(II) complexes are reviewed with the aim of showing how it is possible to relate the experimental data to the electronic structure and the coordination geometry of the complexes. It is hoped that this may be of help to all researchers who need to characterize cobalt(II) complexes or use cobalt(II) as a spectroscopic probe. The data relative to electronic, EPR, MCD, NMR spectra as well as to magnetic susceptibility measurements are interpreted within an Angular Overlap approach. Energy level diagrams are employed to calculate the electronic spectra and then, applying the relevant perturbation μ, g, A values are calculated for different chromophores in different coordination environments. The underlying theory is sketched paying in every case much attention to show the possibility of calculating the electronic properties in low symmetry environments. An extensive compilation of available experimental data is presented. The chromophores are classified according to the coordination number and according to the donor atom set.

190 citations


Journal ArticleDOI
TL;DR: In this paper, the effect of a range of organic phase additives such as isodecanol and tributyl phosphate on the performance of the extraction of cobalt and nickel has been examined.

178 citations




Journal ArticleDOI
TL;DR: In this article, the effect of varying the cobalt loading, calcination temperature, and sample pretreatment conditions was studied for NO adsorption on Co Al 2 O 3 and CoAl 2 O 4 catalysts.

163 citations


Journal ArticleDOI
TL;DR: In this article, a cobalt electrode in base to repetitive triangular potential sweeps over the range 0.2 V(RHE) resulted in the formation of a thick hydrous oxide film.

152 citations


Journal ArticleDOI
TL;DR: This article showed that the presence of cobalt or nickel improves the reducibility of iron based catalysts and increases the Fe2+/Fe3+ ratio in the mixed oxide catalyst precursors.

143 citations


Book
01 Jan 1982

Journal ArticleDOI
01 Nov 1982
TL;DR: In this paper, cobalt ferrites were prepared by aging at 90°C either coprecipitated iron and cobalt hydroxides from aqueous solutions of Co(N03)2 and FeSO4, or (B) ferrous hydroxide gels in contact with Co(II) salt solutions.
Abstract: Cobalt ferrites were prepared by aging at 90°C either (A) coprecipitated iron(II) and cobalt(II) hydroxides from aqueous solutions of Co(N03)2 and FeSO4, or (B) ferrous hydroxide gels in contact with Co(II) salt solutions. In both cases KNO3 was added to act as a mild oxidizing agent. Magnetic particles were formed when the equivalent concentration of metal ions exceeded that of the hydroxide ion. The chemical composition and the morphology of particles varied with the concentrations of the reacting components in the original solutions. Under certain conditions spherical particles of narrow size distributions were obtained.


Journal ArticleDOI
TL;DR: Mittels potentiometrischer Messungen werden die Protonierungskonstanten des makrocyclischen Liganden (I) bei 25°C untersucht as mentioned in this paper.
Abstract: Mittels potentiometrischer Messungen werden die Protonierungskonstanten des makrocyclischen Liganden (I) bei 25°C untersucht.


Journal ArticleDOI
TL;DR: A Parafilm disk floating on saline and bearing a drop of cobalt solution in which the nerve stump is bathed provides a convenient and versatile method for in vitro or in vivo filling of neurons for cobalt sulfide staining.
Abstract: A Parafilm disk floating on saline and bearing a drop of cobalt solution in which the nerve stump is bathed provides a convenient and versatile method for in vitro or in vivo filling of neurons for cobalt sulfide staining. Silicone grease around the edge of the disk provides an effective seal around the nerve as it passes between the two solutions.Using a modified developer, silver intensification of cobalt sulfide stained neurons may be done in the light at room temperature, and the time of optimum intensification may be observed under a dissecting microscope.

Journal ArticleDOI
TL;DR: Ten women with known allergy to nickel showed clear-cut or strong patch test reactions to the alloy with 7% nickel, and in five patients with contact allergy reactions to both nickel and cobalt salts mild or marked responses to some of the other alloys were observed.
Abstract: Test pieces from five cobalt-chromium casting alloys intended for use in removable partial dentures were attached to the skin of 10 women with known allergy to nickel. Patch tests were also performed with nickel and cobalt salts. Nine of the 10 women showed clear-cut or strong patch test reactions to the alloy with 7% nickel, one patient also to one of the other alloys (less than 1% nickel). In five patients with contact allergy reactions to both nickel and cobalt salts mild or marked responses to some of the other alloys were observed. Corresponding observations were made in three out of the five patients with contact allergy reactions to nickel salt but not cobalt salt.

Journal ArticleDOI
TL;DR: In this paper, a non-symmetrical, tetradentate Schiff base has been obtained in a two-step process, in which one mole of ethylene diamine is reacted with one Mole of acetylacetone to afford a 1:1 condensation product, which is then reacted with Mole of either salicylaldehyde or 2-hydroxyacetophenone to yield nonsymmetric diimines.

Journal ArticleDOI
TL;DR: The structural characteristics of Co/Mo/Al/sub 2/O/sub 3/ hydrodesulfurization catalysts have been investigated with a variety of surface spectroscopic techniques as mentioned in this paper.
Abstract: The structural characteristics of Co/Mo/Al/sub 2/O/sub 3/ hydrodesulfurization catalysts have been investigated with a variety of surface spectroscopic techniques: ESCA, ISS, and photoacoustic spectroscopy (PAS). All catalysts were prepared by sequential impregnation of Mo and Co into ..gamma..-Al/sub 2/O/sub 3/ with the Mo concentration held constant at 15% MoO/sub 3/ by weight as the cobalt concentration was varied from 1 to 9% CoO. In all catalysts interaction between Co and the support was observed which rendered a portion of the Co inert toward H/sub 2/ reduction and H/sub 2/S sulfidation. This interaction species (Co-t) is dominant for catalysts of low cobalt loading (i.e., 1% CoO). As the cobalt concentration is increased a new phase is formed characterized by interactions between Co and Mo. This species (Co-M) is produced up to a concentration of 7% CoO. Above this level, Co/sub 3/O/sub 4/ is formed. From ISS it was determined that the Co ions were situated beneath the Mo ions as Co-t and the Co-Mo interaction species. The presence of cobalt was found to have no effect on the reduction or sulfidation of Mo. 10 figures, 5 tables.



Journal ArticleDOI
TL;DR: In this paper, a study of the oxidation states of metals in selected Pacific ferromanganese nodules by x-ray photoelectron spectroscopy (XPS) indicates the presence of Co(III, Pb(II), Pb-IV, Fe(III) and Ti(IV).

Journal ArticleDOI
TL;DR: In this article, an upper layer of Co3O4 and subsequent layers of CoO down to the substrate were used for spray pyrolysis on stainless steel substrates kept at 300°C.

Journal ArticleDOI
TL;DR: In this article, the potentiodynamic response of cobalt in KOH solutions (10−2 M ⩽c⩽2.5 M) in the potential range of the thermodynamic stability of the Co(II) species reveals two limiting electrochemical behavirours.

Journal ArticleDOI
TL;DR: In this paper, the interaction of oxygen with recrystallized Co has been studied using AES, Δφ and UPS techniques, and it was found that oxygen adsorb dissociatively at T ⩾ 120 K with high sticking coefficient.

Journal ArticleDOI
TL;DR: In this paper, a transmission electron microscope study of several precipitation hardened cobalt rare earth magnets has been conducted and a fine cellular microstructure was revealed, which is strongly influenced by the shape and size of the cellular structure as well as by the lattice misfit between the 5:1 and 17:2 phases.

Patent
19 Nov 1982
TL;DR: In this paper, methods for forming protective diffusion layers on nickel, cobalt and iron base alloy parts comprising the formation of a diffusion layer of platinum, chromium and aluminum on said surfaces were provided.
Abstract: Methods are provided for forming protective diffusion layers on nickel, cobalt and iron base alloy parts comprising the formation of a diffusion layer of platinum, chromium and aluminum on said surfaces either by deposition of platinum and gas phase chromizing followed by aluminizing or by gas phase chromizing and deposition of platinum followed by aluminizing, or by gas phase chromizing followed by aluminizing and deposition of platinum, said gas phase chromizing performed out of contact with a source of gaseous chromizing species at elevated temperature, said aluminizing performed either out of contact or in contact with a powder mixture at elevated temperature.

Journal ArticleDOI
TL;DR: In this paper, a mechanism of low-temperature hot corrosion is proposed based on rapid dissolution of the more noble metal or metal oxide in liquid salts. But it is not shown that the dissolution of cobalt oxides can prevent the formation of a protective Cr2O3 or A12O3 film.
Abstract: This paper presents a mechanism of low-temperature hot corrosion that is based on rapid dissolution of the more noble metal or metal oxide in liquid salts. It is proposed that the rapid degradation of cobalt-base alloys results from dissolution of cobalt or cobalt oxides on the surface, which prevents the formation of a protective Cr2O3 or A12O3 film. The reaction occurs in two stages: (a) an initial stage, during which an Na2SO4-CoSO4 liquid forms on the surface, and (b) a propagation stage, during which SO3 migrates inward and cobalt outward through the molten salt. At longer times, cobalt dissolves at the scale/salt interface and forms Co3O4 and/or CoSO4(s) in different regions of the reaction product. The mechanisms of transport of various reactants and products through the liquid salt and the effects of their relative transport rates on the reaction product morphology have been considered.


Journal ArticleDOI
TL;DR: In this paper, the absolute oscillator strength of neutral cobalt was determined from hook measurements for 159 transitions and emission intensity measurements for 314 transitions between 2276 A and 9357 A.
Abstract: Absolute oscillator strengths of neutral cobalt have been determined from hook measurements for 159 transitions and emission intensity measurements for 314 transitions between 2276 A and 9357 A. Ninety-five of these transitions were subjected to the procedure developed by Cardon, Smith, and Whaling which fits combined absorption and emission data to a set of consistent, optimum, relative oscillator strengths and upper level lifetimes. These relative values were normalized to the radiative lifetimes of Figger et al. and of Marek and Vogt obtained by pulsed laser fluorescence. Absolute oscillator strengths for 362 transitions and 36 lifetimes were determined. Typical uncertainties in the reported absolute oscillator strengths are +- 15-25% (2/3 confidence level). Equivalent widths were obtained for nineteen solar cobalt lines with the McMath solar telescope at Kitt Peak National Observatory. These widths were used to redetermine the solar cobalt abundance, assuming the photospheric model of Holweger and a microturbulence velocity of 1.0 km s/sup -1/. The adopted solar cobalt abundance is the mean value log +12 = 4.92 +- 0.08 ( +- 19%), from the 19 cobalt transitions. This value is in excellent agreement with the solar values of Ross and Aller, of Biemont, and of Holweger and that ofmore » Cameron for carbonaceous chondrites.« less