Within the framework of the closed box model of chemical evolution of galaxies the evolution
of nitrogen and oxygen abundances in dwarf irregular galaxies is considered. We show that …

On the Evolution of Helium Nitrogen and Oxygen Abundances in Dwarf Irregular Gal ADS
Classic is now deprecated. It will be completely retired in October 2019. This page will …

Numerical models of chemical evolution have been computed for a sample of 40 dwarf
irregular galaxies by assuming bursts of star formation and taking galactic winds into …

Deep groundbased spectra of Hubble V and Hubble X, the two largest and brightest H ii
regions in the Local Group dwarf galaxy, NGC 6822, are presented. The extinction …

We present long-slit optical spectroscopy of 67 H II regions in 21 dwarf irregular galaxies to
investigate the enrichment of oxygen, nitrogen, neon, sulfur, and argon in low-mass …

The observed oxygen abundances in a number of irregular galaxies have been compared
with predictions of the closed-box model for chemical and photometric evolution of galaxies …

The low-luminosity dwarf irregular galaxies are considered. The oxygen abundances in H ii
regions of dwarf irregular galaxies were recalculated from published spectra through the …

In order to recognize environmental effects on the evolution of dwarf galaxies in clusters of
galaxies, it is first necessary to quantify the properties of objects that have evolved in relative …

We present abundances of neon, nitrogen and oxygen of some nearby dwarf irregular
galaxies. The elemental abundances are retrieved from long-slit spectroscopy of H ii regions …

Optical spectra of H ii regions of two dwarf irregular galaxies are presented. The objects are
IC 4662 and ESO 245-G05. Chemical abundances were derived in all the H ii regions where …