Keystone has hired Dennis Senackerib as the new technical sales representative for the Mid-Atlantic region. Mr. Senackerib will call on accounts for Keystone in southern New York, New Jersey, eastern Pennsylvania, Delaware and Maryland, reporting to Ed Messer, Keystone regional sales manager.      Prior to joining Keystone, Mr. Senackerib worked as a technical sales representative for GEO Specialty Chemicals. He has also worked for Tricon Colors with its line of ink jet dyes, and Tikkurila Inc...