This is a study of the catalysed reduction of cobalt (IT) to metal by carbon monoxide from aqueous, ammoniacal solutions between 180 and 230°C and from 0 to 50 atm. CO. The reaction proceeds through the intermediate formation of a cobalt carbonyl anion. Under the conditions of this study this intermediate is produced homogeneously, and also heterogeneously in the presence of cobalt sulfide. Metal formation occurs only in the presence of cobalt sulfide. The stoichiometry of the production of cobalt carbonyl anion is consistent with the equation. [ Equation omitted ] Metal formation follows stoichiometry of the equation [ Equation omitted ] The following equations represent a mechanism that is consistent with the kinetic observations: [ Equations omitted ] A side reaction involving carbon monoxide and hydroxyl ion produces formate ion, In the presence of cobalt sulfide, hydrogen rather than formate ion is the product. The following equations represent a mechanism that is consistent with experimental observations: [ Equations omitted ] A method for the separation of cobalt (II) from nickel (II) in aqueous solution is suggested. / Applied Science, Faculty of / Materials Engineering, Department of / Graduate

The 4.6m millimeter wave telescope at the University of British Columbia has been used to map a region 1/2° in diameter centered on 1=30°, b=0° in the J=1->0 transition of ¹²C¹⁶0. This study of the inner edge of the galactic molecular ring has revealed two well defined giant molecular clouds with diameters of approximately 30 pc and masses in the order of 5 x 10⁵ M⊙. In addition our analysis indicates that a substantial fraction, amounting to approximately 30%, of the integrated CO intensity comes from a feature covering the entire field observed. We have also found a complex of four clouds whose linewidths are a factor of two greater than those of the standard giant molecular clouds. The nature of these clouds is at present uncertain. The number of clouds detected in our survey gives as 5000 the total number of giant molecular clouds in the galaxy. / Science, Faculty of / Physics and Astronomy, Department of / Graduate

The thesis describes some aspects of the aqueous solution chemistry of chlororuthenate(III) and chlorocarbonylruthenate(III or II) complexes including their reactivity toward carbon monoxide. This led to the synthesis and characterisation of a polymeric complex [HRu(CO)₃][sub n], which is formally a Ru(I) derivative. The use of these ruthenium complexes for activating CO catalytically was studied, especially for the carbonylation of amines. The [HRu(CO)₃][sub n] polymer was characterised by microanalysis, infra-red and high-field ¹H n.m.r. , and its chemistry In donor solvents in which it was soluble. The polymer may be formed by reductive carbonylation of chloro complexes of Ru[sup II], Ru[sup III](CO), Ru[sup II] (CO), Ru[sup II] (C0)₂ and Ru[sup II]CO)₃, and stoichiometric evidence suggests processes such as: [chemical reactions 1 to 4]. Increasing acidity and chloride concentration inhibit the reductive carbonylation process, which likely requires simultaneous coordination of cis CO and OH ligands. Reactions (1) - (4) are accompanied by formation of smaller amounts of low valent ruthenium complexes including Ru₃(CO)₁₂, which could result from a reductive carbonylation process such as [chemical reaction 5] or via 'combination' of Ru[sup I] and Ru[sup -I] species. Evidence is presented for reaction (5) starting with CsRu(CO)₃Cl₃. Reductive carbonylation 2- of Ru(CO)₂Cl₄⁻² (reaction (4)) shows autocatalytic gas uptake plots, indicating catalysis of the reaction via a Ru(0) or Ru(I) intermediate. The kinetics for the carbonylation of piperidine to N-formyl piperidine catalysed by each of the complexes [HRu(CO)₃][sub n], [Ru(CO)₂(OAc)(pip)]₂, and CsRu(CO)₃Cl₃, have been studied under mild conditions. Mechanisms are proposed to explain the observed kinetics and in each case a tricarbonyl monomeric species appears to be the active catalyst. A CO insertion reaction in a Ru(CO)₃ (pip)[sub x] intermediate must be involved. A scheme such as (6) e.g. [chemical reaction 6] requires a hydride shift, likely metal activated. Alternatively, piperidine could behave as a proton acceptor with the reaction proceeding via a carbamoyl intermediate (reaction (7)). [chemical reaction 7] Both [HRu(CO)₃][sub n] and CsRu(C0)₃Cl₃ carbonylate piperidine in a stoichiometric reaction in the absence of CO, and in the case of the cesium salt evidence suggests the following reactions: [chemical reactions 8-9] Only secondary amines were carbonylated effectively. Attempts to isolate and characterise ruthenium complexes via the reactions [HRu(CO)₃][sub n] or CsRu(C0)₃Cl₃with piperidine proved frustrating, although one complex isolated from the polymer reaction is thought to be H₂Ru₂(CO)₄(pip)₃, and an oxygenated solution of [HRu(CO)₃][sub n] in piperidine yielded a complex which analysed well for [HRu(CO)₂(pip)]₂•0₂. / Science, Faculty of / Chemistry, Department of / Graduate

The angle, distance and vibration dependence of the Ar-CO intermolecular potential is calculated using the electron gas model to obtain the short range interaction which is smoothly joined onto the long range van der Waals tail which is obtained from accurate C_6, C_7, and C_8 coefficients. Our calculated second interaction virial coefficients are compared with experiment and with a simple adjustment of the Ar-CO potential an excellent agreement is obtained. Our spherically averaged potential is also in excellent agreement with a spherical potential inferred from high energy scattering data. Simplified expressions for the scattering amplitude and differential cross section are obtained in the infinite order sudden approximation. Then, treating the rotations and vibrations in the infinite order sudden and close coupling approximations respectively, vibrational transition probabilities and relaxation rates are calculated using the Ar-CO intermolecular potential. Our calculated vibrational relaxation rates are much smaller than the experimental values.

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In this thesis, the results of oxidation and decarburization experiments with pure iron-carbon alloys over the temperature range 800 - 950ºc, and in atmospheres of varying carbon monoxide - carbon dioxide ratio are reported. Most of the experimental work is concerned with a 1.065 weight percent carbon alloy at temperatures where austenite is the stable phase. Complex kinetic behaviour was observed for this alloy in the range 10 - 100 volume percent carbon dioxide. An analysis is given which in turn associates the kinetics with a pure diffusion controlled decarburization model and a pure surface controlled decarburization model. The latter best represents the interaction of the decarburization mechanism with the scaling process on Y - iron. Metallographic evidence is provided where possible in support of the results of the afore-mentioned analysis. Mathematical relations are introduced which attempt to describe qualitatively the kinetics of the carbon alloys in all the atmospheres employed. A statement is made as to the applicability of the model to carbon steels in general at temperatures where austenite is the stable phase and where the atmospheres employed are of various carbon monoxide - carbon dioxide ratio. / Thesis / Master of Science (MS)

Thesis (M.S.)--Virginia Polytechnic Institute and State University, 1993. / Vita. Abstract. Includes bibliographical references (leaves 60-62). Also available via the Internet.

Thesis--Copenhagen University. / Summary in Danish. Bibliography: p. [119]-141.