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 Chemical Analysis and Material Characterization by Spectrophotometry written by Bhim Prasad Kaflé and published by Elsevier. This book was released on 2019-11-29 with total page 314 pages. Available in PDF, EPUB and Kindle. Book excerpt: Chemical Analysis and Material Characterization by Spectrophotometry integrates and presents the latest known information and examples from the most up-to-date literature on the use of this method for chemical analysis or materials characterization. Accessible to various levels of expertise, everyone from students, to practicing analytical and industrial chemists, the book covers both the fundamentals of spectrophotometry and instrumental procedures for quantitative analysis with spectrophotometric techniques. It contains a wealth of examples and focuses on the latest research, such as the investigation of optical properties of nanomaterials and thin solid films. - Covers the basic analytical theory that is essential for understanding spectrophotometry - Emphasizes minor/trace chemical component analysis - Includes the spectrophotometric analysis of nanomaterials and thin solid films - Thoroughly describes methods and uses easy-to-follow, practical examples and experiments
Download or read book 15N Tracing of Microbial Assimilation Partitioning and Transport of Fertilisers in Grassland Soils written by Alice Fiona Charteris and published by Springer Nature. This book was released on 2019-10-28 with total page 289 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book presents innovative research on soil nitrogen cycling and nitrate leaching with a view to improving soil management and fertiliser nitrogen use efficiency and reducing nitrogen leaching losses. In this regard, nitrogen-15 (15N)-labelled fertiliser was used as a biochemical and physical stable isotope tracer in laboratory and field experiments. The major outcome of the research was the development, validation and application of a new compound-specific amino acid 15N stable isotope probing method for assessing the assimilation of fertiliser nitrogen by soil microbial biomass. The novelty of the method lies in its tracing of incorporated nitrogen into newly biosynthesised microbial protein in time-course experiments using gas chromatography-combustion-isotope ratio mass spectrometry. The approach provides previously unattainable insights into the microbial processing of different nitrogen fertilisers in different soils. Further, it identifies the mechanistic link between molecular-scale processes and observations of field-scale fertiliser nitrogen immobilisation studies. The method and the results presented here will have far-reaching implications for the development of enhanced recommendations concerning farm-based soil management practices for increasing soil productivity and reducing nitrogen losses, which is essential to minimising environmental impacts.
Download or read book Nanobiotechnology for Sustainable Food Management written by Eduardo Alberto López-Maldonado and published by CRC Press. This book was released on 2024-10-25 with total page 646 pages. Available in PDF, EPUB and Kindle. Book excerpt: Among the most novel and ever-growing approaches to improving the food industry is nanobiotechnology. In this book, the prospective role of nanobiotechnology in food which includes quality control and safety through nanosensors and biosensors, targeted delivery of nutrients, controlled release of nutrients, proteins, antioxidants, and flavors through encapsulation and enzymatic reactions for food fortification of fat-soluble compounds is discussed. Along the chapters of this book, nanobiotechnological techniques are addressed in detail with specific emphasis on food science applications. Features: Discusses nanobiotechnology in food for quality control and safety Covers food processing and packaging for food safety Explores the positive role of nanomaterials towards the sustainability of food Provides efficient, real, and sustainable solutions to pertinent global problems Includes case studies and research directions of the nanobiotechnology This book is aimed at researchers and graduate students in nanotechnology and food engineering.
Download or read book Ecohydrological Interfaces written by Stefan Krause and published by John Wiley & Sons. This book was released on 2023-10-12 with total page 437 pages. Available in PDF, EPUB and Kindle. Book excerpt: Ecohydrological Interfaces Comprehensive overview of the process dynamics and interactions governing ecohydrological interfaces Summarizing the interdisciplinary investigation of ecohydrological interface functioning, Ecohydrological Interfaces advances the understanding of their dynamics across traditional subject boundaries. It offers a detailed explanation of the underlying mechanisms and process interactions governing ecohydrological interface functioning from the micro scale to the ecosystem and regional scale. The multidisciplinary team of authors integrates and synthesises the current understanding of process dynamics at different ecohydrological interfaces to develop a unifying concept of their ecosystem functions. The work introduces novel experimental and model-based methods for characterizing and quantifying ecohydrological interface processes, taking account of innovative sensing and tracing technologies as well as microbial and molecular biology approaches. Key questions addressed in the book include: Which conditions stimulate the transformative nature of ecohydrological interfaces? How are ecohydrological interfaces organized in space and time? How does interface activity propagate from small to large scales? How do ecohydrological interfaces react to environmental change and what is their role in processes of significant societal value? As a research level text on the functionality and performance of ecohydrological interfaces, Ecohydrological Interfaces is primarily aimed at academics and postgraduate researchers. It is also appropriate for university libraries as further reading on a range of geographical, environmental, biological, and engineering topics.
Download or read book Analytical Properties of Some Commercially Available Nitrate Reductase Enzymes Evaluated as Replacements for Cadmium in Automated Semiautomated and written by Charles J Patton and published by CreateSpace. This book was released on 2014-08-01 with total page 46 pages. Available in PDF, EPUB and Kindle. Book excerpt: A multiyear research effort at the U.S. Geological Survey (USGS) National Water Quality Laboratory (NWQL) evaluated several commercially available nitrate reductase (NaR) enzymes as replacements for toxic cadmium in longstanding automated colorimetric air-segmented continuous-flow analyzer (CFA) methods for determining nitrate plus nitrite (NOx) in water. This research culminated in USGS approved standard- and low-level enzymatic reduction, colorimetric automated discrete analyzer NOx methods that have been in routine operation at the NWQL since October 2011. The enzyme used in these methods (AtNaR2) is a product of recombinant expression of NaR from Arabidopsis thaliana (L.) Heynh. (mouseear cress) in the yeast Pichia pastoris. Because the scope of the validation report for these new automated discrete analyzer methods, published as U.S. Geological Survey Techniques and Methods 5-B8, was limited to performance benchmarks and operational details, extensive foundational research with different enzymes-primarily YNaR1, a product of recombinant expression of NaR from Pichia angusta in the yeast Pichia pastoris-remained unpublished until now. This report documents research and development at the NWQL that was foundational to development and validation of the discrete analyzer methods. It includes: (1) details of instrumentation used to acquire kinetics data for several NaR enzymes in the presence and absence of known or suspected inhibitors in relation to reaction temperature and reaction pH; and (2) validation results-method detection limits, precision and bias estimates, spike recoveries, and interference studies-for standard- and low-level automated colorimetric CFA-YNaR1 reduction NOx methods in relation to corresponding USGS approved CFA cadmium-reduction (CdR) NOx methods. The cornerstone of this validation is paired sample statistical and graphical analysis of NOx concentrations from more than 3,800 geographically and seasonally diverse surface-water and groundwater samples that were analyzed in parallel by CFA-CdR and CFA enzyme-reduction methods. Finally, (3) demonstration of a semiautomated batch procedure in which 2-milliliter analyzer cups or disposable spectrophotometer cuvettes serve as reaction vessels for enzymatic reduction of nitrate to nitrite prior to analytical determinations. After the reduction step, analyzer cups are loaded onto CFA, flow injection, or discrete analyzers for simple, rapid, automatic nitrite determinations. In the case of manual determinations, analysts dispense colorimetric reagents into cuvettes containing post-reduction samples, allow time for color to develop, insert cuvettes individually into a spectrophotometer, and record percent transmittance or absorbance in relation to a reagent blank. Data presented here demonstrate equivalent analytical performance of enzymatic reduction NOx methods in these various formats to that of benchmark CFA-CdR NOx methods.
Download or read book Scientific Investigations Report written by Sharon E. Kroening and published by . This book was released on 2004 with total page 122 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Practical Guidelines for the Analysis of Seawater written by Oliver Wurl and published by CRC Press. This book was released on 2009-06-09 with total page 404 pages. Available in PDF, EPUB and Kindle. Book excerpt: As we discover more about the role of the ocean in global changes and identify the effects of global change on the ocean, understanding its chemical composition and processes becomes increasingly paramount. However, understanding these processes requires a wide range of measurements in the vast ocean, from the sea surface to deep-ocean trenches, fr
Download or read book Methods of Seawater Analysis written by Klaus Grasshoff and published by John Wiley & Sons. This book was released on 2009-07-30 with total page 632 pages. Available in PDF, EPUB and Kindle. Book excerpt: Since the book first appeared in 1976, Methods of Seawater Analysis has found widespread acceptance as a reliable and detailed source of information. Its second extended and revised edition published in 1983 reflected the rapid pace of instrumental and methodological evolution in the preceding years. The development has lost nothing of its momentum, and many methods and procedures still suffering their teething troubles then have now matured into dependable tools for the analyst. This is especially evident for trace and ultra-trace analyses of organic and inorganic seawater constituents which have diversified considerably and now require more space for their description than before. Methods to determine volatile halocarbons, dimethyl sulphide, photosynthetic pigments and natural radioactive tracers have been added as well as applications of X-ray fluorescence spectroscopy and various electrochemical methods for trace metal analysis. Another method not previously described deals with the determination of the partial pressure of carbon dioxide as part of standardised procedures to describe the marine CO2 system.
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 Determination of Anions written by Thomas R. Crompton and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 598 pages. Available in PDF, EPUB and Kindle. Book excerpt: The author has drawn together almost all published methods since 1975 on the determination of anions in all types of matrices. He presents the methods in a logical manner so that the reader can quickly gain access to the method and types of instrumentation available.
Download or read book Recent Progress in Slow Sand and Alternative Biofiltration Processes written by Rolf Gimbel and published by IWA Publishing. This book was released on 2006-03-31 with total page 580 pages. Available in PDF, EPUB and Kindle. Book excerpt: Slow sand filtration is typically cited as being the first "engineered" process in drinking-water treatment. Proven modifications to the conventional slow sand filtration process, the awareness of induced biological activity in riverbank filtration systems, and the growth of oxidant-induced biological removals in more rapid-rate filters (e.g. biological activated carbon) demonstrate the renaissance of biofiltration as a treatment process that remains viable for both small, rural communities and major cities. Biofiltration is expected to become even more common in the future as efforts intensify to decrease the presence of disease-causing microorganisms and disinfection by-products in drinking water, to minimize microbial regrowth potential in distribution systems, and where operator skill levels are emphasized. Recent Progress in Slow Sand and Alternative Biofiltration Processes provides a state-of-the-art assessment on a variety of biofiltration systems from studies conducted around the world. The authors collectively represent a perspective from 23 countries and include academics, biofiltration system users, designers, and manufacturers. It provides an up-to-date perspective on the physical, chemical, biological, and operational factors affecting the performance of slow sand filtration (SSF), riverbank filtration (RBF), soil-aquifer treatment (SAT), and biological activated carbon (BAC) processes. The main themes are: comparable overviews of biofiltration systems; slow sand filtration process behavior, treatment performance and process developments; and alternative biofiltration process behaviors, treatment performances, and process developments.
Download or read book Groundwater Quality written by Harriet Nash and published by Springer. This book was released on 1994-10-31 with total page 204 pages. Available in PDF, EPUB and Kindle. Book excerpt: Groundwater quality monitoring and testing is of paramount importance both in the developed and developing world. This book presents a series of papers illustrating the varied nature of current research into groundwater quality. Urban and rural supplies are covered through a case history approach, and the importance of remedial action to prevent deterioration is emphasized.
Download or read book Drinking Water Distribution Systems written by National Research Council and published by National Academies Press. This book was released on 2006-12-22 with total page 404 pages. Available in PDF, EPUB and Kindle. Book excerpt: Protecting and maintaining water distributions systems is crucial to ensuring high quality drinking water. Distribution systems-consisting of pipes, pumps, valves, storage tanks, reservoirs, meters, fittings, and other hydraulic appurtenances-carry drinking water from a centralized treatment plant or well supplies to consumers' taps. Spanning almost 1 million miles in the United States, distribution systems represent the vast majority of physical infrastructure for water supplies, and thus constitute the primary management challenge from both an operational and public health standpoint. Recent data on waterborne disease outbreaks suggest that distribution systems remain a source of contamination that has yet to be fully addressed. This report evaluates approaches for risk characterization and recent data, and it identifies a variety of strategies that could be considered to reduce the risks posed by water-quality deteriorating events in distribution systems. Particular attention is given to backflow events via cross connections, the potential for contamination of the distribution system during construction and repair activities, maintenance of storage facilities, and the role of premise plumbing in public health risk. The report also identifies advances in detection, monitoring and modeling, analytical methods, and research and development opportunities that will enable the water supply industry to further reduce risks associated with drinking water distribution systems.
Download or read book Analytical Techniques in Biochemistry and Molecular Biology written by Rajan Katoch and published by Springer Science & Business Media. This book was released on 2011-07-19 with total page 449 pages. Available in PDF, EPUB and Kindle. Book excerpt: Advances in biochemistry now allow us to control living systems in ways that were undreamt of a decade ago. This volume guides researchers and students through the full spectrum of experimental protocols used in biochemistry, plant biology and biotechnology.
Download or read book Manual for the Certification of Laboratories Analyzing Drinking Water written by and published by . This book was released on 1992 with total page 24 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Handbook of Food Analysis Two Volume Set written by Leo M.L. Nollet and published by CRC Press. This book was released on 2015-06-10 with total page 1530 pages. Available in PDF, EPUB and Kindle. Book excerpt: Updated to reflect changes in the industry during the last ten years, The Handbook of Food Analysis, Third Edition covers the new analysis systems, optimization of existing techniques, and automation and miniaturization methods. Under the editorial guidance of food science pioneer Leo M.L. Nollet and new editor Fidel Toldra, the chapters take an in
