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The conditions for carrying out the condensation of 1,2-dihydropyrrolizine, 2-methyl-1,2-dihydropyrrolizine, and 3-methyl-1,2-dihydropyrrolizine with ethylene oxide were investigated. The NMR spectra indicated that hydroxyethylation proceeds at the 5 and 7 positions of the 1,2-dihydropyrrolizine system.

The storage multifunctional oscillograph is a measuring instrument which provides preliminary processing of the investigated signals. This processing consists of determining the separate parameters of the signal, representing it in the required form, and matching the parameters with the potentialities of the processing devices. The oscillograph is free from design redundancy inherent in sets of instruments which accumulate simple measurement.

The stereochemistry of the catalytic hydrogenation of 5- and 7-(β-hydroxyethyl)-1,2-dihydropyrrolizines on 2.5% Rh/Al2O3 and Raney nickel under various conditions has been studied. On the basis of information on the configurational catalytic isomerization and the competing quaternization of the isomers, a consideration of the relative retention times, and an analysis of the geometries of the molecules of the 1- and 3-(β-hydroxyethyl)pyrrolizidines a configurational assignment of the stereoisomers has been made.

Die Hydrierung der Dihydropyrrolidine (I) und (IV) uber 2,5% Rh/AI2O3 und Raney-Nickel fuhrt zu Gemischen der Verbindungen (II) und (III) und (V) und (VI), wobei jeweils die Bildung der cis-Verbindungen (II) und (V) uberwiegt.

A mixture consisting of n homogeneous phases having certain properties is considered. The geometry of the phase domains is arbitrary and the mixture as a whole is considered to be statistically homogeneous but generally anisotropic. Ideal conditions of thermal contact (a continuous temperature and thermal flux) at the phase boundary are assumed. A variational method is used to find both the upper and lower bounds of the effective thermal-conductivity coefficients of the mixture for given concentrations and the thermal-conductivity coefficients of the individual phases.