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The cylinder withdrawal theory for power‐law fluids proposed by Tallmadge has been compared with continuous withdrawal data in this work. Calculated withdrawal speeds differ greatly from measured values, although Tallmadge's gravity‐corrected theory for Newtonian fluids is in agreement with the present data on Newtonian fluids. Correlations similar to that of Goucher and Ward have been developed with the experimental data over a 400‐fold range of dimensionless withdrawal speeds. These correlations are applicable for prediction of non‐Newtonian liquid film thicknesses on vertical wires and also apparently for viscoelastic fluids like CMC solutions, but are not applicable for inelastic fluids like Carbopol 934.

Vapour phase catalytic oxidation of quinoline over a vanadia base catalyst yielded nicotinic acid, while vapour phase catalytic ammoxidation gave 3‐cyano‐pyridine, the benzenoid ring undergoing cleavage in both cases. The isomeric molecule, isoquinoline, was however found to behave in sharp contrast, undergoing an unexpected reaction in its transformation into phthalimide during identical conditions of oxidation and into ortho‐phthalonitrile during ammoxidation, the pyridine ring undergoing cleavage in both cases, with the appearance of the heterocyclic ring nitrogen in a reactive functional group. The significance of these observations is discussed in relation to structure and reactivity and possible reaction mechanisms are suggested.

A three‐parameter model for mass transfer by absorption, based on a combined effect of non‐steady‐state molecular and eddy diffusion through a resistance zone has been suggested, which encompasses all the existing theories on mass transfer at the gas‐liquid interface. King's approach [5] to describing gas‐liquid mass transfer phenomena through an eddy‐diffusivity model can explain some experimental results, but does not provide a general mathematical solution of the problem. The shortcomings of the King's model are overcome in the present work and a general solution is presented. This solution confirms the experimental findings of Versteeg et al. [10] for liquid phase mass transfer. The steady‐state solution of the present theory, valid for the dimensionless number α > 0, shows a close agreement with experimental data of Luk [22], the only source of all the information necessary for model verification.

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