Briefs
NBS TRACEABLE CALIBRATION GAS STANDARDS
Determination of Lead and Cadmium in Fish and Clam Tissue by Atomic Absorption Spectrometry with a Molybdenum and Lanthanum Treated Pyrolytic Graphite Atomizer 1147 Under Typical conditions, average analytical recoveries are within 90-110% for lead and cadmium, and peak height reproducibility is ~ 2 - 3 % when working sufficiently above detection limits. J. E. Poldoski, U.S. Environmental Protection Agency, Environmental Research Laboratory—Duluth, 6201 Congdon Boulevard, Duluth, Minn. 55804 Anal. Chem., 52 (1980)
Correspondence Comments on Regression through the Origin
1151
Roger R. W. Ellerton, Department of Mathematics and Statistics, University of New Brunswick, Post Office Box 4400, Fredericton, N.B. E3B 5A3 Canada and Frederick C. Strong III, Faculdade de Engenharia de Alimentos e Agricola, Universidade Estadual de Campinas, Caixa Postal No. 1170, 13100 Campinas, S.P., Brasil Anal. Chem., 52 (1980)
Exchange of Comments on Neutron Activation Analyses for Simultaneous Determination of Trace Elements in Ambient Air Collected on Glass-Fiber Filters 1153 R. D. Gilbert and R. E. Fornes,* Department of Textile Materials and Management, School of Textiles, North Carolina State University, Box 5006, Raleigh, N.C. 27650 and J. P. F. Lambert* and F. W. Wilshire, U.S. Environmental Protection Agency, Trace Elements Analysis Section, Analytical Chemistry Branch, Environmental Monitoring and Support Laboratory, Research Triangle Park, N.C. 27711 Anal. Chem., 52 (1980)
Aids for Analytical Chemists
Polar Bonded-Phase Sorbents for High Performance Liquid Chromatographic Separations of Polycyclic Aromatic Hydrocarbons 1154
To meet the performance standards of the Environmental Protection Agency, stationary sources required to continuously monitor for gaseous pollutants must be calibrated and audited with calibration gas standards that are both accurate and stable. When it's time to calibrate your continuous monitor, you can rely on Matheson's NBS Traceable Gas Mixtures. Matheson makes gas mixture standards for air pollutants such as sulfur dioxide, nitric oxide, nitrogen dioxide, oxygen, carbon dioxide and carbon monoxide. Component concentrations in these calibration mixtures are traceable to the National Bureau of Standards, Standard Reference Materials via the EPA Traceability Protocol No. 1 or No. 2, dated June 15,1978. Each of these gas mixtures is compared to an NBS Standard Reference Material either directly, or through a gas manufacturer's primary standard which is referenced to an NBS Standard Reference Material. The stability of each reactive gas standard is verified before shipment and a written analysis is included with the cylinder to certify it has been analyzed according to the Protocol. For a current list of Matheson gas standards prepared via the EPA Traceability Protocol, write to Matheson, 1275 Valley Brook Avenue, P.O. Box E, Lyndhurst, NJ 07071. CIRCLE 125 ON READER SERVICE CARD
HEAVY-DUTY CYLINDER TRANSPORTATION Moves cylinders easily even on gravel Safely handle and transport compressed gas cylinders with Matheson's new, Model 6502 heavy-duty hand trucks. Large, hi-load capacity wheels, precision balancing and rear carriage supports allow easy maneuverability through crowded laboratories or plant areas. Matheson heavy-duty hand trucks can be used with all size cylinders and are easily rolled over all types of surfaces, even gravel beds. Matheson, 1275 Valley Brook Avenue, P.O. Box E, Lyndhurst, NJ 07071
Jan Chmielowicc* and Albert E. George, Energy Research Laboratories, c/o 555 Booth Street, Ottawa, Ontario K1A 0G1, Canada Anal. Chem., 52 (1980)
Determination of Ethyl Sulfate by Reversed-Phase Ion Pair Chromatography 1157 Grace Chiu, Monsanto Chemical Intermediates Company, P.O. Box 12830, Pensacola, Fla. 32575 Anal. Chem., 52 (1980)
(Continued on page 724 A)
CIRCLE 126 ON READER SERVICE CARD 722 A • ANALYTICAL CHEMISTRY, VOL. 52, NO. 7, JUNE 1980
