Comparison of Far-Infrared Optical, and Radiofrequency Data of Diffuse Nebulae

The relation of far-infrared grain emission to bremsstrahlung in gas-and-dust nebulae is discussed. Application is made to diffuse nebulae in a 100- catalog which are identified with sources in 6-cm catalogs. Comments are made on some individual objects and on the significance of the observed 8(100 )/S(6 cm) ratio of flux densities. Subject headings:nebulae - infrared - radio radiation