Download or read book Colorimetric Determination of Nitrate Plus Nitrite in Water by Enzymatic Reduction Automated Discrete Analyzer Methods written by Charles J Patton and published by CreateSpace. This book was released on 2014-06-16 with total page 44 pages. Available in PDF, EPUB and Kindle. Book excerpt: 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.
Download or read book Method for the Determination of Nitrate and Nitrite in Waters written by and published by . This book was released on 1977 with total page 16 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Environmental Research and Protection written by W. Fresenius and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 304 pages. Available in PDF, EPUB and Kindle. Book excerpt: Inorganic chemical pollutants such as S02 and NO. , which also act as the major precursors of acid rain, as well as ecotoxic heavy metals and metalloids (cadmium, lead, mercury, copper, zinc, nickel, chromium, arsenic, selenium etc. ) have gained considerable significance as regards the ecotoxic burden on vegetation, soil and natural waters, and as air pollutants. The rapid increase that has recently been noticed in severe damage to forests has suddenly aroused public interest in the ever-growing problem of inorganic chemical pollutants to a hitherto unknown extent, especially as in addition to the damage to vegetation, this also constitutes a growing hazard for man via food chains. Research on the level, fate and transfer as well as on the ecotoxic and toxic impact of inorganic pollutants has therefore gained considerable significance in science and furthermore as a sound scientific basis for relevant environmental protection regulations, in research politics and in public awareness.
Download or read book Nitrate Contamination written by Istvan Bogardi and published by Springer Science & Business Media. This book was released on 2013-06-29 with total page 438 pages. Available in PDF, EPUB and Kindle. Book excerpt: The nitrate content of drinking water is rising at an alarming rate in several regions of NATO countries and elsewhere in the world. The increase is due to lack of proper sewage treatment, and primarily to excess fertilizer application. Also, eutrophication in several coastal areas is triggered by high nitrate concentrations. The main purpose of this book is to integrate scientific knowledge related to exposure assessment, health consequences and control of nitrate contamination in water. The motivation is related to the magnitude, the possible adverse health effects, and the high cost of control ling nitrate contamination. Future research tasks are defined by an interaction among hydro logists, toxicologists and environmental engineers in an integrated framework for nitrate risk management. The target readership of this book is a mix of university colleagues, practitioners from both the private and public sectors and advanced graduate students working with the hydrological, health science or environmental engineering aspects of nitrate contamination. The main conclusions include: 1. For risk assessment purposes, knowledge and sufficiently accurate models are available to predict nitrate load and its fate in water under changes in land use. 2. Once agricultural exposure controls are implemented, the response times in ground water may be so long as to make controls unrealistic. 3. It is still unknown whether agricultural best management practice is a compromise between nitrate risk reduction and agricultural revenue. 4. The current drinking water guidelines of 10 mg/L NOrN need not be changed.
Download or read book Nitrates and Nitrites in Food and Water written by Michael J Hill and published by CRC Press. This book was released on 1996-07-01 with total page 208 pages. Available in PDF, EPUB and Kindle. Book excerpt: From the Introduction With regard to nitrate and nitrite, the perceived hazards are to the ecological balance in rivers and lakes, and to human health. Increased nitrate levels in river water lead to increased growth of algae and consequent decrease in the level of biologically available oxygen (BAO). In extreme forms, the algae form unsightly blooms on the water surface, and the BAO level falls below that necessary to support fish and other animal life. At this extreme, there is little dispute that efforts should be made to restore the ecological balance, and this is best achieved by reversing the increase in nitrate concentration that caused the problem. The health hazards are less clear, but include the risk of methaemoglobinaemia in young infants and the possible risk of gastric cancer, particularly in certain high-risk patient groups. These health risks have led to legislation to control the exposure of humans to nitrate from drinking water and as a food additive . . . What can be done about this and how can the problem be solved (if, indeed, there is a problem)? It is normal practice to add nitrate and nitrite to food as a cosmetic and as a preservative. Is this necessary? If so, how much do we need to add? Are there alternatives? What effect does added nitrate have on total nitrate exposure of humans? . . . In this book, we have attempted to answer, or at least to give the background to, some of the questions. . . .
Download or read book Method 353 4 written by Jia-Zhong Zhang and published by . This book was released on 1997 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Quantifying Uncertainty in Analytical Measurement written by Eurachem/CITAC Working Group and published by . This book was released on 2000-01-01 with total page 120 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book New Methods of Nitrite and Nitrate Analysis for Natural Waters written by Patrick John Canney and published by . This book was released on 1973 with total page 336 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Smart Nitrate Sensor written by Md Eshrat E. Alahi and published by Springer. This book was released on 2019-05-09 with total page 132 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book presents the design and development of an Internet of Things (IoT) enabled, smart sensor to detect nitrate contamination in natural water. It considers three different sensors designed, fabricated and configured for nitrate detection: a Graphite/PDMS and Si-based MEMS sensors, and aFR4-based sensor. It also introduces a selective polymer material developed by means of the ion imprinting polymerization technique that was used as a coating on the Si-based MEMS sensor. Further, the book discusses the development of a smart sensing system that can be used to remotely monitor the nitrate concentration in any water. Fully explaining all the techniques used, the book is of interest to engineers, researchers and scientists working in the field of the water-quality measurement.
Download or read book Handbook of Water Analysis Third Edition written by Leo M.L. Nollet and published by CRC Press. This book was released on 2013-07-29 with total page 999 pages. Available in PDF, EPUB and Kindle. Book excerpt: Extensively revised and updated, Handbook of Water Analysis, Third Edition provides current analytical techniques for detecting various compounds in water samples. Maintaining the detailed and accessible style of the previous editions, this third edition demonstrates water sampling and preservation methods by enumerating different ways to measure chemical and radiological characteristics. It gives step-by-step descriptions of separation, residue determination, and clean-up techniques. See What’s New in the Second Edition: Includes five new chapters covering ammonia, nitrates, nitrites, and petroleum hydrocarbons, as well as organoleptical and algal analysis methodology Compares older methods still frequently used with recently developed protocols, and examines future trends Features a new section regarding organoleptical analysis of water acknowledging that ultimately the consumers of drinking water have the final vote over its quality with respect to odor, flavor, and color The book covers the physical, chemical, and other relevant properties of various substances found in water. It then describes the sampling, cleanup, extraction, and derivatization procedures, and concludes with detection methods. Illustrated with procedure flow charts and schematics, the text includes numerous tables categorizing methods according to type of component, origin of the water sample, parameters and procedures used, and application range. With contributions from international experts, the book guides you through the entire scientific investigation starting with a sampling strategy designed to capture the real-world situation as closely as possible, and ending with an adequate chemometrical and statistical treatment of the acquired data. By organizing data into more than 300 tables, graphs, and charts, and supplementing the text with equations and illustrations, the editors distill a wealth of knowledge into a single accessible reference.
Download or read book Determination of Nitrite and Nitrate Ions in Natural Waters Using Aromatic Ortho Diamines as Reagents written by Patrick J. Canney and published by . This book was released on 1974 with total page 40 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Two Methods for the Determination of Nitrates in Water written by Eugene Goldman and published by . This book was released on 1963 with total page 10 pages. Available in PDF, EPUB and Kindle. Book excerpt: This reappraisal of the phenol-disulfonic-acid method for the determination of nitrate shows that it can be adequate if procedural pitfalls are recognized and avoided. The determination of nitrate ion based on its absorption of ultraviolet radiation is also discussed. Results obtained using the ultraviolet absorption method are apparently equivalent to those found by the phenol-disulfonic-acid method based on analysis of a variety of water types. The two methods are discussed and the results obtained are compared.
Download or read book Nitrate and Nitrite in Drinking Water written by and published by National Academies Press. This book was released on 1995-01-01 with total page 77 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Safe Drinking Water Act directs the U.S. Environmental Protection Agency (EPA) to establish national drinking-water standards for chemical and biological contaminants in public water supplies. The standards are to be set at concentrations at which no adverse effects on human health occur or are expected to occur from lifetime consumption, allowing a margin of safety; enforceable standards are standards that are feasible to achieve with the use of the best technology available. The standards are to be reviewed periodically to ensure continued protection of public health. Consistent with the requirement for periodic review, EPA asked the National Research Council to evaluate the current drinking-water maximum-contaminant-level goals (MCLGs) and maximum contaminant levels (MCLs) for nitrate and nitrite in public water supplies. The Subcommittee on Nitrate and Nitrite in Drinking Water, convened under National Research Council procedures, reviewed information on the occurrence and toxicity of nitrate and nitrite. The subcommittee evaluated this information in the context of the drinking-water standards for those substances and drew conclusions about the adequacy of the current standards to protect human health.
Download or read book Determination of Nitrate and Nitrite in Drinking Water by Chemically Suppressed Ion Chromatography written by Mairead Forrestal and published by . This book was released on 1992 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Smartphone Based Detection Devices written by Chaudhery Mustansar Hussain and published by Elsevier. This book was released on 2021-08-21 with total page 462 pages. Available in PDF, EPUB and Kindle. Book excerpt: Smartphone usage has created a new means for detection, analysis, diagnosis and monitoring through the use of new apps and attachments. These breakthrough analytical methods offer ways to overcome the drawbacks of more conventional methods, such as the expensive instrumentation that is often needed, complex sample pre-treatment steps, or time-consuming procedures. Smartphone-Based Detection Devices: Emerging Trends in Analytical Techniques gathers these modern developments in smartphone analytical methods into one comprehensive source, covering recent advancements in analytical tools while paying special attention to the most accurate, highly efficient approaches. Serving as a guide not only to analytical chemists but also to environmentalists, biotechnologists, pharmacists, forensic scientists and toxicologists, Smartphone-Based Detection Devices: Emerging Trends in Analytical Techniques is an important source for researchers who require accurate analysis of their on- and off-site samples. Students in these fields at the graduate and post-graduate level will also benefit from this topical and comprehensive book. Provides an integrated approach for advanced analytical methods and techniques using smartphones Covers the usage of smartphones in sample prep, integration and detection stages of analytical chemistry Applicable for researchers of all levels, from graduate students to professionals
Download or read book The Quantitative Determination of Nitrate and Nitrite in Water by Ultraviolet Absorption written by Robert A. Biggers and published by . This book was released on 1967 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Smart Sensors and Sensing Technology written by Gourab Sen Gupta and published by Springer Science & Business Media. This book was released on 2008-07-01 with total page 408 pages. Available in PDF, EPUB and Kindle. Book excerpt: Technological advancements in recent years have enabled the development of tiny, cheap disposable and self contained battery powered computers, known as sensor nodes or “motes”, which can accept input from an attached sensor, process this input and transmit the results wirelessly to some interested device(s). When a number of these nodes work together, conceivably up to hundreds of thousands, a Wireless Sensor Network (WSN) is formed. Research in the area of wireless sensor networks has become increasingly wid- pread in recent years, partly due to their wide range of potential uses and also partly due to the fact that the technology enabling such networks is now widely available from many di?erent suppliers, such as: Crossbow, MoteIV, Intel and SUN (java based motes). These wireless sensor networks have the potential to allow a level of integration between computers and the physical world that, to date, has been virtually impos- ble. The uses for such networks is almost limitless and include such diverse app- cations as a counter sniper system for urban warfare [1] tracking the path of a forest re [2], determining the structural stability of a building after an earthquake [3], or tracking people or objects inside a building [4], etc.
