73113087
Jan 19, 1977
Mar 18, 1986
METERS AND DETECTORS FOR MEASURING AND MONITORING THE TRANSMITTANCE AND THE COLOR OF PROCESS LIQUIDS: METERS AND DETECTORS FOR MEASURING AND MONITORING THE PH (ACID OR BASE CONDITION), THE ORP (OXIDE-REDUCTION POTENTIAL), AND THE PIOH (SPECIFIC ION CONCENTRATION) OF PROCESS LIQUIDS; AND METERS AND DETECTORS FOR MEASURING AND MONITORING THE LEVEL AND THE FLOW OF PROCESS LIQUIDS
Electrical and Scientific Apparatus