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We have obtained high-resolution echelle spectra of 18 solar-type stars thatan earlier survey showed to have very high levels of Ca II H and K emission.Most of these stars belong to close binary systems, but 5 remain as probablesingle stars or well-separated binaries that are younger than the Pleiades onthe basis of their lithium abundances and H-alpha emission. Three of theseprobable single stars also lie more than 1 magnitude above the main sequence ina color-magnitude diagram, and appear to have ages of 10 to 15 Myr. Two ofthem, HD 202917 and HD 222259, also appear to have a kinematical associationwith the pre-main sequence multiple system HD 98800.Comment: 25 figures, 3 table

High-Resolution Spectroscopy of Some Very Active Southern Stars