Briefs Ultra-High Sensitive H P L C U N I V E R S A L DETECTOR
Fluorescence Quenching Titration for Determination of Complexing Capacities and Stability Constants of Fulvic Acid 986 D a t a t r e a t m e n t includes c o m p u t e r curve-fitting analysis t o o b t a i n c o n s t a n t s for C u 2 + b i n d i n g t o fulvic acid a n d Ltyrosine. Rayleigh s c a t t e r i n g gives i n f o r m a t i o n o n aggregation of Cu 2 + -fulvic acid complexes. David K. Ryan a n d J a m e s H. Weber*, Chemistry Department, University of New Hampshire, Durham, N.H. 03824. Anal. Chem.,54 (1982) Determination of Mercaptans at Microgram-perCubic-Meter Levels in Air by Gas Chromatography with Photoionization Detection 991
ERC-7510
RI DETECTOR
• Highest sensitivity and stability Detection limit : 10 η g/ml (Sucrose/Water) Attenuator range : 1/64-32χ 1CT5 RIU/FS 12 ranges Noise : 0.25xlCT8RIU • High-performance temperature regulator Temp, control : 30, 35, 40, 45, 50 °C, 5 ranges • No optical adjustment required • Rapid washable reference cell with reference valve
Separation of sucrose
T h e d e t e c t i o n limit is 0.06 n g for η - b u t y l m e r c a p t a n a n d 0.02 ng for o t h e r m e r c a p t a n s analyzed. W i t h a 5-mL injection v o l u m e , sensitivity is ~ 2 /^g/m 3 which is as sensitive as d e t e c t i o n by smell. Vincent B . Stein* and Rajinder S. N a r a n g * , Toxicology Institute, Center of Laboratories and Research, New York State Department of Health, Albany, N.Y. 12201 Anal. Chem.,54 (1982) Reduction of Water with Zinc for Hydrogen Isotope Analysis 993 1 m g w a t e r r e d u c e d in a sealed t u b e gives reproducibility of 0.2-0.4% (1σ, replicate analyses). P r e p a r a t i o n t i m e averages 6 m i n . F l u i d inclusions a n d water of h y d r a t i o n a r e analyzed. M a x L. Coleman*, Thomas J. Shepherd, John J. D u r h a m , John E. Rouse, and Gillian R. Moore, Isotope Geology Unit, Institute of Geological Sciences, 64 Gray's Inn Road, London WC1X 8NG, England Anal. Chem., 54 (1982)
Correspondence Integration of Differential Pulse Voltammograms for Concentration Measurements 995 K e n n e t h J . Stutts, M a r k A. Dayton, and R. M a r k Wightman*, Department of Chemistry, Indiana University, Bloomington, Ind. 47405 Anal. Chem., 54 (1982)
• • • • • •
Sample size Sensitivity Chart speed Column Solvent Pressure
0.35 μξ/2.5μ\ 1/16χ10~ 5 RIU/FS 1 cm/min S-801, 8 m m ^ x 250 mm H2O 23 kg/cm 2
For f u r t h e r i n f o r m a t i o n , c o n t a c t
ERMA OPTICAL WORKS, LTD. Scientific Instruments Department 2-4-5, Kajicho, Chiyoda-ku Tokyo, 101 Japan Telex : J25301 ERMAWORK Cable ; ERMAW0RKS TOKYO
CIRCLE 64 ON READER SERVICE CARD
674 A · ANALYTICAL CHEMISTRY, VOL. 54, NO. 6, MAY 1982
Exchange of Comments on Evaluation of the Copper Anodic Stripping Voltammetry Complexometric Titration for Complexing Capacities and Conditional Stability Constants 998 Mark S. Shuman, Department of Environmental Sciences & Engineering, School of Public Health, University of North Carolina at Chapel Hill, Chapel Hill, N.C. 27514 P . L. Brezonik, Department of Civil and Mineral Engineering, University of Minnesota, Minneapolis, Minn. 55455, and J. R. Tuschall, Jr.*, Department of Environmental Engineering Sciences, University of Florida, Gainesville, Fla. 32611 Anal. Chem., 54 (1982)
