Hach DR/700 Procedures Manual page 754

TECHNICAL SUPPORT,
continued
"pH Measurement Problems Solved". By Gale McGaha Miller.
Reprinted from American Laboratory News Edition, October, 1988.
This article compares the conventional reference junction used in most
pH electrodes and the free diffusion reference junction used in Hach pH
electrodes.
Plating and Surface Finishing
"Heavy Metal Removal Using Dithiocarbamates".
By R.E. Wing and W.E. Rayford. Reprinted from Plating & Surface
Finishing, January, 1982.
Dithiocarbamates effectively precipitate heavy metals from plating rinse
water over a wide pH range. Concentrations of residual metal are well
below established EPA discharge limits.
"Know Your Water Quality: Influent and Effluent". By Tom Haukebo.
Reprinted from Plating & Surface Finishing, November, 1986.
Discusses how knowledge of the quality of water at both ends of the
surface finishing process is critical for product quality, cost control and
legal reasons. Methods are available for the simple and reliable
determination of water quality without the need for outside services and
within the requirements of environmental regulations.
"Sodium Hypophosphite Analysis in Electroless Nickel". By Diane M.
Tramontana. Reprinted from Metal Finishing, December, 1986.
In the smaller job shop, where expensive analytical equipment cannot be
justified, wet analytical methods are recommended for monitoring the
sodium hypophosphite concentrations used in electroless nickel plating.
Process Analysis
Introduction to: The Pump-Colorimeter Analyzer. By Paul Larson,
Charles Gibbs, Clifford Hach and David Schnoover, 1987.
Describes development of a continuous-reading on-line analyzer for
water and wastewater, Topics covered are: design objectives, mechanical
operation, optical design, and electronics. Also covered are field test
results for free chlorine in drinking water, total chlorine in sewage, and
orthophosphate in sewage.
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