Carbon and nitrogen abundances in early B-stars I. NLTE calculations for asample of stars with small v sin i values

Abundances of carbon and nitrogen in a sample of hot main sequence stars we re determined in the NLTE approximation. All calculations were based on Kur ucz atmosphere models. Atmospheric parameters for the program stars have be en determined using spectroscopic and photometric methods. In most cases the derived atmospheric abundances appear to be subsolar and probably unaltered by stellar evolution. This is in agreement with the gene ral conclusions on C and N abundances for B main sequence stars reached by other investigators.