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The process of gel formation in the reaction of polycyclotrimerization of 2,2‐bis(4‐cyanatophenyl) propane has been studied as a function of the nature of solvent, monomer concentration, kind and concentration of catalyst, temperature of the process, and the way in which the reaction is conducted. The gel point and the dependence of the gel yield on the degree of the system conversion vary with the conditions of the process conduction and the solvent used. It was found also that the type of the catalyst affects the parameters indicated above only in certain solvents. A change in the monomer concentration has been found to affect differently the gel point of the system, depending on the nature of the solvent. The experimental data obtained have been compared with the results of the theory of gel formation developed for the process of polycyclotrimerization by Fukui and Yamabe. The dependence of the process kinetics on the type and concentration of catalysts has been investigated. No marked influence of temperature on the regularities of gel formation has been disclosed.

The emission of positronium negative ions from Cs deposited W(100) surfaces has been studied. A dramatic change in the emission efficiency was observed upon coating a W(100) surface with Cs. The conversion efficiency (the fraction of incident slow positrons yielding the ions) of the W(100) target with a 2.2 × 10 14 atoms cm −2 Cs coverage, measured over a time interval of 3 × 10 3 s immediately after deposition, was found to be 1.25%, which is two orders of magnitude higher than that obtained for the clean, uncoated W(100) surface and 45 times greater than the highest efficiency reported thus far.