LETTERS Needed: award nominees Dear Sir: The ACS Award for Creative Advances in Environmental Science and Technology was established in 1978 by Air Products and Chemicals, Inc. and will be presented for the first time in 1980. Requests for nominations and additional information should be directed to Dr. Justin W. Collat at the American Chemical Society, I155 16th Street, N.W., Washington, D.C. 20036. The nomination deadline for the 1980 award is March 1 , 1979. The purpose of this award is to encourage creativity in research and technology or methods of analysis to provide a scientific basis for informed environmental control decisionmaking processes, or to- provide practical technologies that will reduce healthrisk factors.
The award consists of $2000, a certificate of recognition, and an allowance of not more than $350 for travel expenses incidental to the conferral of the award. Julian B. Andelman Chairman of the Canvassing Committee University of Pittsburgh Pittsburgh, Pa. 15261
Particles Dear Sir: I read with interest the article entitled “Particle Sampling and Measurement” (ES&T, August 1978, p 881). We at the University of Washington have been conducting research on cascade impactors since about 1968, and have developed a number of cascade impactor models including the Mark 3, Mark 4, and
Permeation devices
Mark 5 models, which are patented and licensed out by the University of Washington to the Pollution Control Systems Corp. (Renton, Washington) for manufacture and marketing. Recently we have developed Mark I O (samples at 0.2 acfm for high particle concentrations such as at inlets to control equipment) and Mark 20 (samples at 2 acfm for low particle concentrations such as at outlets of control equipment) models under an EPRI contract, these models being designed for simultaneous sampling at the inlet and outlets of particle collection systems on electric utility power plants. Our U. of W. Source Test Cascade Impactors are reported to be advantageous for use in obtaining particle samples for later chemical analysis because the U. of W. impactors do not have to use the glass fiber filter substrate (the glass interferes with many chemical analysis techniques). Dr. John Ondov, Lawrence Livermore Laboratory, has presented a number of papers on the use of our impactors in ES& T, Atmospheric Environment, and the APCA Journal. Michael J. Pilat, Professor Dept. of Civil Engineering University of Washington Seattle. Wash. 98195
by experts When you need a gas permeation device, Metronics is your best source of expert help. Our DynacaF line is the most complete in the industry, covering over 100 gases. Permeation rates range from nanograms per minute to milligrams per minute. Even if you have an unusual requirement (e.g. exotic gas, nonstandard rate), we’ll gladly make recommendations. In most cases, we can supply a device customtailored to your application. Dynacal permeation devices fit most calibrators and internally calibrated analyzers now on the market, including Philips analyzers and Monitor Labs calibrators. In addition, we have the largest inventory in the industry. So, you’ll get prompt delivery. CIRCLE 14
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For a quotation, or additional information about applications for these precision, low concentration gas sources, call or write: Metronics, 2991 Corvin Drive, Santa Clara, CA 95051. (408) 737-0550.
meant gas (pure liquid phase) aling gas (rate
Calibration you can count on.
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Environmental Science & Technology
is function
Cyanide discharge Dear Sir: A news release on our cyanide removal process (ES&T, August 1978, p 975) stated incorrectly that Amberlitem IRA-958 converts cyanide to a metallic complex. As our brochure explains, cyanide in solution is first converted to ferrocyanide and ferricyanide by the addition of ferrous sulfate. The metallic cyanide complexes already in solution and those created by addition of ferrous sulfate are then effectively removed from solution by adsorption onto Amberlite IRA-958. Amberlite IRA-958 takes no part in the conversion of cyanide to a metallic complex, J. C. Fanelli Rohm and Haas Company Philadelphia, Pa. 19105
