Theories of urban size and growth have assumed that innovativeness is more common to larger cities. This paper tests the relationship between three measures of scientific employment, and the population of U. S. metropolitan areas. Elasticities of scientific employment with respect to city size and nonlinear functions of city size suggest that innovative ability of the largest urban areas declined somewhat from 196 to 1972. Diseconomies of size for scientific activity may be becoming dominant in thelargest cities in contrast to prevailing assumptions about the advantages of urban size.
Authors:B. Małecka, E. Drożdż-Cieśla and A. Małecki
Thermal decomposition of CoC2O4⋅2H2O was studied using DTA, TG, QMS and XRD techniques. It was shown that decomposition generally occurs in two steps: dehydration
to anhydrous oxalate and next decomposition to Co and to CoO in two parallel reactions. Two parallel reactions were distinguished
using mass spectra data of gaseous products of decomposition. Both reactions run according toAvrami–Erofeev equation. For
reaction going to metallic cobalt parameter n=2 and activation energy is 9714 kJ mol–1. It was found that decomposition to CoO proceeds in two stages. First stage (0.12<αII<0.41) proceeds according to n=2, with activation energy 25115 kJ mol–1 and second stage (0.45<αII<0.85) proceeds according to parameter n=1 and activation energy 20321 kJ mol–1.