A PHYSICO-CHEMICAL SYSTEM FOR WATER AEROSOL MEASUREMENT

摘要

The need for a durable, precision collecting surface for water aerosols has led to the development of a new transparent 35-mm film sensitive to distilled water and sea water fog droplets in the size range 1 to 100μ. The droplet indicating film is polyvinyl alcohol containing silver nitrate and hydrogen peroxide coated on a substrate of 35-mm cellulose acetate film leader stock. A unique development process employing gaseous phenylhydrazine, ammonia, water vapor, and ultraviolet light from a sun lamp defines the impressions left by the droplets. The salt water impressions are sharply distinguished from distilled water spots by in¬tense color differences. Large scale tests defining important variables and film sensitivity have been made. Special techniques are developed which allow collections of radioisotope tagged water droplets to be identified by radioautographic methods.nTo meet the requirements of a large scale field sampling program, instruments which automatically and continuously prepare, develop, and assist in the analysis of large volumes of the special film have been developed.