GET pH FOR EXTRA MEASURE.
The Martek Mark X This self-contained waterquality moni tor measures temperature, conductivity, and salinity. Add the optional pH and we still are priced lower than competi tive systems without pH. With or without the pH measurement . capability, the rugged but lightweight Mark X operates under the harshest of environmental conditions, as well as in the laboratory. It combines simplicity of operation with fast and accurate answers. Forfurther information, contact Martek Instruments, Inc., 17302 Daimler St., P.O. Box 16487, Irvine, Calif. 92713, Telephone (714) 540-4435, Telex 692-317.
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622 A · ANALYTICAL CHEMISTRY, VOL. 53, NO. 4, APRIL 1981
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