Author: Publisher:
ISBN:
Category : Environment sampling
Languages : en
Pages : 4
Book Description
Quality Control at the U.S. Geological Survey, National Water Quality Laboratory
Author: Interpreting and Reporting Radiological Water-quality Data
Author: David E. McCurdyPublisher:
ISBN:
Category : Environmental sampling
Languages : en
Pages : 33
Book Description
Quality Control Manual of the U.S. Geological Survey's National Water Quality Laboratory
Author: Berwyn E. JonesPublisher:
ISBN:
Category : Water
Languages : en
Pages : 22
Book Description
U.S. Geological Survey Quality-assurance Project for Sediment Analysis
Author: J. D. GordonPublisher:
ISBN:
Category : Sedimentation analysis
Languages : en
Pages : 8
Book Description
Methods of Analysis by the U.S. Geological Survey National Water Quality Laboratory
Author: Virendra Kumar JhaPublisher:
ISBN:
Category : Flame photometry
Languages : en
Pages : 46
Book Description
Evaluation of Quality Assurance/quality Control Data Collected by the U.S. Geological Survey for Water-quality Activities at the Idaho National Engineering Laboratory, Idaho, 1989 Through 1993
Author: Linda M. WilliamsPublisher:
ISBN:
Category : Water quality
Languages : en
Pages : 130
Book Description
Evaluation of Quality-assurance/quality-control Data Collected by the U.S. Geological Survey from Wells and Springs Between the Southern Boundary of the Idaho National Engineering and Environmental Laboratory and the Hagerman Area, Idaho, 1989 Through 1995
Author: Linda M. WilliamsPublisher:
ISBN:
Category : Groundwater
Languages : en
Pages : 92
Book Description
Colorimetric Determination of Nitrate Plus Nitrite in Water by Enzymatic Reduction, Automated Discrete Analyzer Methods
Author: Charles J PattonPublisher: CreateSpace
ISBN: 9781500223311
Category : Technology & Engineering
Languages : en
Pages : 44
Book Description
This report documents work at the U.S. Geological Sur- vey (USGS) National Water Quality Laboratory (NWQL) to validate enzymatic reduction, colorimetric determinative meth- ods for nitrate + nitrite in filtered water by automated discrete analysis. In these standard- and low-level methods (USGS I-2547-11 and I-2548-11), nitrate is reduced to nitrite with nontoxic, soluble nitrate reductase rather than toxic, granular, copperized cadmium used in the longstanding USGS auto- mated continuous-flow analyzer methods I-2545-90 (NWQL laboratory code 1975) and I-2546-91 (NWQL laboratory code 1979). Colorimetric reagents used to determine resulting nitrite in aforementioned enzymatic- and cadmium-reduction meth- ods are identical. The enzyme used in these discrete analyzer methods, designated AtNaR2 by its manufacturer, is produced by recombinant expression of the nitrate reductase gene from wall cress (Arabidopsis thaliana) in the yeast Pichia pastoris. Unlike other commercially available nitrate reductases we evaluated, AtNaR2 maintains high activity at 37°C and is not inhibited by high-phenolic-content humic acids at reaction temperatures in the range of 20°C to 37°C. These previously unrecognized AtNaR2 characteristics are essential for success- ful performance of discrete analyzer nitrate + nitrite assays (henceforth, DA-AtNaR2) described here.
Methods of Analysis by the U.S. Geological Survey National Water Quality Laboratory
Author: Publisher:
ISBN:
Category : Government publications
Languages : en
Pages : 104
Book Description
National Water Information System (NWIS).
Author: Publisher:
ISBN:
Category : Water resources development
Languages : en
Pages : 2
Book Description