Thematische Bibliographien / Water quality – Eurasia – Measurement

Auswahl der wissenschaftlichen Literatur zum Thema „Water quality – Eurasia – Measurement“

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Veröffentlicht am 26. Juli 2024

Zuletzt aktualisiert am 27. Juli 2024

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Zeitschriftenartikel zum Thema "Water quality – Eurasia – Measurement"

Sussmann, R., T. Borsdorff, M. Rettinger, C. Camy-Peyret, P. Demoulin, P. Duchatelet, E. Mahieu und C. Servais. „Technical Note: New trends in column-integrated atmospheric water vapor – Method to harmonize and match long-term records from the FTIR network to radiosonde characteristics“. Atmospheric Chemistry and Physics Discussions 9, Nr. 3 (16.06.2009): 13199–233. http://dx.doi.org/10.5194/acpd-9-13199-2009.

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Abstract. We present a method for harmonized retrieval of integrated water vapor (IWV) trends from existing, long-term, measurement records at the ground-based mid-infrared solar FTIR spectrometry stations of the Network for the Detection of Atmospheric Composition Change (NDACC). Correlation of IWV from FTIR with radiosondes shows an ideal slope of 1.00(3). This optimum matching is achieved via tuning one FTIR retrieval parameter, i.e., the strength of a Tikhonov regularization constraining the derivative (with respect to height) of retrieved water profiles given in per cent difference relative to an a priori profile. All other FTIR-sonde correlation parameters (intercept =0.02(12) mm, bias =0.02(5) mm, standard deviation of coincident IWV differences (stdv)=0.27 mm, R=0.99) are comparable to or better than results for all other ground-based IWV sounding techniques given in the literature. An FTIR-FTIR side-by-side intercomparison reveals a strong exponential increase in stdv as a function of increasing temporal mismatch starting at Δt ~1 min. This is due to atmospheric water vapor variability. Based on this result we derive an upper limit for the precision of the FTIR IWV retrieval for the smallest Δt(=3.75 min) still giving a statistically sufficient sample (32 coincidences), i.e., precision (IWVFTIR)<0.05 mm (or 2.2% of the mean IWV). The bias of the IWV retrievals from the two different FTIR instruments is nearly negligible (0.02(1) mm). The optimized FTIR IWV retrieval is set up in the standard NDACC algorithm SFIT 2 without changes to the code. A concept for harmonized transfer of the retrieval between different stations deals with all relevant control parameters; it includes correction for differing spectral point spacings (via regularization strength), and final quality selection of the retrievals (excluding the highest residuals (measurement minus model), 5% of the total). The method is demonstrated via IWV trend analysis from the FTIR records at the Zugspitze (47.4° N, 11.0° E, 2964 m a.s.l.) and Jungfraujoch (46.5° N, 8.0° E, 3580 m a.s.l.) NDACC stations. Trend analysis comprises a linear fit after subtracting an intra-annual model (3 Fourier components) and constructing an uncertainty interval (95% confidence) via bootstrap resampling. For the Zugspitze a significant trend of 0.79 (0.65, 0.92) mm/decade is found for the time interval (1996–2008). There is a significantly increased trend of 1.41 (1.14, 1.69) mm/decade in the second part of the time series (2003–2008) compared to 0.63 (0.20, 1.06) mm/decade in the first part (1996–2002). For the Jungfraujoch no significant trend is found in any of the periods (1988–2008), (1996–2008), (1996–2002), or (2003–2008). The results imply either an altitude dependency with a significantly higher trend below 3.58 km than above, and/or strong, regional variations of IWV trends on the scale of ~250 km. This is in line with a widespread, complex, IWV trend picture over Eurasia during the last decades. Our paper provides a basis for future exploitation of more than a dozen existing, multi-decadal FTIR measurement records around the globe for joint IWV trend studies within NDACC that complement existing trend data sets which are based primarily on radiosondes.

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Muto, Giichi. „Some Ploblems on Water Quality Measurement“. Japan journal of water pollution research 8, Nr. 11 (1985): 689. http://dx.doi.org/10.2965/jswe1978.8.689.

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Danilov-Danilyan, V. I., E. G. Larina und O. M. Rozental. „Measurement Accuracy in Water Quality Control“. Water Resources 50, Nr. 1 (Februar 2023): 168–78. http://dx.doi.org/10.1134/s0097807823010062.

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Danilov-Danilyan, V. I., E. G. Larina und O. M. Rozental. „Measurement Accuracy in Water Quality Control“. Водные ресурсы 50, Nr. 1 (01.01.2023): 113–24. http://dx.doi.org/10.31857/s0321059623010066.

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It is well-known that the error of a measurement result can increase at each step of a laboratory procedure, as well as because of the sample character of partial measurements. To overcome these difficulties, close cooperation between hydrologists and analytical chemists is required in order to obtain reliable information about the composition and properties of natural waters, which are extremely unstable. The study focuses on details that are of importance for both the client-hydrologist and the performer—chemist-analyst. The article gives different variants of conclusions regarding the compliance or non-compliance with the established requirements. The cost of reliable measurements is calculated, and variants of optimization of enterprise’s payments for discharges are proposed. Recommendations are given to customers regarding the choice of a competent analytical laboratory.

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Kwak, Pill Jae, Seog Ku Kim, Sang Leen Yun, Sung Won Kang, Hyun Dong Lee, Keun Ho Yang, Hee Jae Oh und Young Sung Kim. „Development of Multiple Water Quality Measurement Devices“. Materials Science Forum 695 (Juli 2011): 606–9. http://dx.doi.org/10.4028/www.scientific.net/msf.695.606.

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The water quality measurement device that we developed measures pH, water temperature, conductivity, dissolved oxygen, turbidity and nitrate. And it measures all parameters simultaneously. The water resistant and screw packing technology also applied for improved mechanical reliability during water quality monitoring. A comparison between the performances of major company products (YSI, Hydrolab etc.) and this device don't provide a stark contrast. This device was verified through the KOREA’s Environmental Examination Methods. This device is offered reliable and cost-effective water quality monitoring solutions. Upgrades will be available and will include the technologies that are self-cleaning optical sensors with integrated wipers remove biofouling and maintain high data accuracy and optimal power management and built-in battery compartment extends in situ monitoring periods.

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Goda, Takeshi. „Monitoring and measurement of water quality parameters“. International Journal of Water Resources Development 4, Nr. 4 (Dezember 1988): 270–75. http://dx.doi.org/10.1080/07900628808722401.

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., Priyanka N. Bande. „A SURVEY OF WATER QUALITY MEASUREMENT SENSORS“. International Journal of Research in Engineering and Technology 05, Nr. 06 (25.06.2016): 161–65. http://dx.doi.org/10.15623/ijret.2016.0506031.

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IFUKU, Makoto, Teruya MASUMOTO, Hikaru SAEKI und Masato NAKATA. „CONTINUOUS MEASUREMENT OF WATER QUALITY WITH WATER-QUALITY PROFILING SYSTEM AT NOMURA RESERVOIR“. Journal of Japan Society of Civil Engineers, Ser. B1 (Hydraulic Engineering) 67, Nr. 4 (2011): I_1567—I_1572. http://dx.doi.org/10.2208/jscejhe.67.i_1567.

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Takács, Attila, Attila Molnár V., Balázs A. Lukács, Timea Nagy, Ádám Lovas-Kiss, Andy J. Green, Agnieszka Popiela und Lajos Somlyay. „Resurrection and typification of Elatine campylosperma (Elatinaceae), a long-forgotten waterwort species“. PeerJ 6 (29.05.2018): e4913. http://dx.doi.org/10.7717/peerj.4913.

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The name Elatine campylosperma Seub. is generally treated as one of the synonyms of E. macropoda Guss. However, recent morphological, phylogenetic and karyological studies indicate that this judgement should be revised. In the present paper we typify the name E. campylosperma, review its taxonomic history and provide a thorough description, with compilation of previously published data and our new measurements from in vitro cultures. Based on our herbarium survey, we outline its Atlantic-Mediterranean distribution area (Spain, France, Italy, Greece, Turkey and Algeria). Habitat preferences are summarized from our field observations, water quality measurements and the label information of the herbarium specimens examined. Intact E. campylosperma seeds were found in faecal samples of the Eurasian Coot (Fulica atra L.) in southern Spain and two of them were germinated, suggesting that E. campylosperma has a capacity for long distance dispersal via endozoochory.

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Oberoi, K., S. Purohit, P. A. Verma, A. Deshmukh, S. Saran und P. Chauhan. „GEOSPATIAL BASED CITIZEN CENTRIC WATER QUALITY MEASUREMENT SOLUTION“. ISPRS - International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences XLII-5 (19.11.2018): 75–78. http://dx.doi.org/10.5194/isprs-archives-xlii-5-75-2018.

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<p><strong>Abstract.</strong> Citizen science has emerged as a game changer in various scientific endeavors, wherein scientific data for understanding the phenomenon could be collected by volunteers/non-specialist in a quick possible time. Citizens nowadays play an important role by functioning as “sensors” helping government/institutions by collecting and analyzing data. The advancements and convergence of technologies (Information and communication technologies (ICT)), especially the Internet and mobile technology has further assisted in such efforts. Moreover, the location sensors (GPS) and camera on board the mobile devices enables citizens to collect geotagged data. The classic example is the OpenStreetMap project where volunteers contribute towards the mapping of the planet. This paper highlights the geospatial solution based on citizen science to collect geotagged data about the water quality (turbidity). This solution is developed using open source tools and consists of an Android based mobile app and web based dashboard on the server side for real time data visualization and analysis. The web application is designed and developed using PHP, JavaScript, HTML & CSS and allows user to view the interpolated geotagged data about water quality over various background maps like OSM, Bhuvan etc. PostgreSQL/PostGIS are used as the backend geospatial data server for storing the geotagged dataset. Such solution will be very useful for water quality monitoring as part of national level project like Clean Ganga Mission using the citizen centric approach.</p>

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Dissertationen zum Thema "Water quality – Eurasia – Measurement"

Jiang, Meng. „Evaluation of Low-Cost Water Quality Measurement System“. Thesis, Mittuniversitetet, Avdelningen för elektronikkonstruktion, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:miun:diva-27179.

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Water is a very important element in our daily life, being able to check the water quality by ourselves would be a useful project to improve our life quality. My idea is to create something cheap and easy to examine the water quality and test it to see if it is capable for outdoor using as well. In this project I chose a DS18B20 as a temperature sensor. To get a system which can work as a water pump I chose an L298P as a motor driver board to support the electric motor, a Hall flow meter to get the flow and quantity, and a Water sensor to get the conductivity. With the Arduino and the Visual Studio user interface program, the system can extract the data that we want. The result of the measurement shows it is possible to analyse the water quality by comparing the conductivity of the known liquid to a test sample in a controlled environment. The system shows great promise of being a cheaper and easier system but still needs to improve accuracy, by reducing outside influence (like temperature), thereby enabling the system to work in more harsh environments.

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Bujatzeck, Baldur. „Statistical evaluation of water quality measurements“. Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1998. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape11/PQDD_0017/MQ44134.pdf.

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Saberi, Atefeh. „Automatic outlier detection in automated water quality measurement stations“. Master's thesis, Université Laval, 2015. http://hdl.handle.net/20.500.11794/25908.

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Des stations de mesure de la qualité de l’eau sont utilisées pour mesurer la qualité de l'eau à haute fréquence. Pour une gestion efficace de ces mesures, la qualité des données doit être vérifiée. Dans une méthode univariée précédemment développée, des points aberrants et des fautes étaient détectés dans les données mesurées par ces stations en employant des modèles à lissage exponentiel pour prédire les données au moment suivant avec l’intervalle de confiance. Dans la présente étude, ne considérant que le cas univarié, la détection de points aberrants est améliorée par l’identification d’un modèle autorégressif à moyenne mobile sur une fenêtre mobile de données pour prédire la donnée au moment suivant. Les données de turbidité mesurées à l'entrée d'une station d'épuration municipale au Danemark sont utilisées comme étude de cas pour comparer la performance de l’utilisation des deux modèles. Les résultats montrent que le nouveau modèle permet de prédire la donnée au moment suivant avec plus de précision. De plus, l’inclusion du nouveau modèle dans la méthode univariée présente une performance satisfaisante pour la détection de points aberrants et des fautes dans les données de l'étude de cas.
Water quality monitoring stations are used to measure water quality at high frequency. For effective data management, the quality of the data must be evaluated. In a previously developed univariate method both outliers and faults were detected in the data measured by these stations by using exponential smoothing models that give one-step ahead forecasts and their confidence intervals. In the present study, the outlier detection step of the univariate method is improved by identifying an auto-regressive moving average model for a moving window of data and forecasting one-step ahead. The turbidity data measured at the inlet of a municipal treatment plant in Denmark is used as case study to compare the performance of the use of the two models. The results show that the forecasts made by the new model are more accurate. Also, inclusion of the new forecasting model in the univariate method shows satisfactory performance for detecting outliers and faults in the case study data.

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Rajele, Molefi Joseph. „A comparison of SAAS and chemical monitoring of the rivers of the Lesotho Highlands Water Project“. Thesis, University of the Western Cape, 2004. http://etd.uwc.ac.za/index.php?module=etd&amp.

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The Lesotho Highlands Development Authority routinely uses the South African Scoring System version 4 (SASS4) in conjunction with water chemistry to monitor water quality of rivers in the Lesotho Highlands Water Project areas. The objective of this study was to test the efficiency of SASS4 in these areas.

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Sharpe, Taylor Jeffery. „Assessing a Fluorescence Spectroscopy Method for In-Situ Microbial Drinking Water Quality“. PDXScholar, 2017. https://pdxscholar.library.pdx.edu/open_access_etds/3838.

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Waterborne disease is a significant contributor to the global burden of disease, in particular among high-risk populations in developing nations. State-of-the-art methods for the enumeration of microbial pathogens in drinking water sources have important limitations, including high initial cost, 24-48 hour delays in results, high staffing and facility requirements, and training requirements which all become especially problematic in the developing nation context. A number of alternative approaches to microbial water quality testing have been proposed, with the goal of decreasing the required testing time, decreasing overall costs, leveraging appropriate technology approaches, or improving sensitivity or specificity of the water quality testing method. One approach that may offer solutions to some of these limitations involves the deployment of sensor networks using fluorescent spectroscopy to detect intrinsic protein fluorescence in water samples as a proxy for microbial activity. In recent years, a number of researchers have found significant and meaningful correlations between indicator bacteria species and the protein fluorescence of drinking water samples. Additionally, advances in the semiconductor industry could be used to drive down the cost of such sensors. This technology may also be extensible to other water quality parameters, including dissolved organic matter or the presence of fluorescent pollutants. In this thesis, a literature review describes the fundamentals of fluorescence spectroscopy, historical and recent work regarding the fluorescence of the amino acid tryptophan and associated bacterial fluorescence, possible mechanisms for this association, and potential applications of this technology for drinking water quality monitoring and waste water process control. Extensibility of the technology is also discussed. Next, experimental methodology in reproduction of similar results is described. Samples were taken from seven (7) surface water sources and tested using membrane filtration and an off-the-shelf fluorescence spectrometer to help examine the association between the presence of indicator bacteria and the tryptophan fluorescence of the water sample. The results, showing an association of R2 = 0.560, are compared to the results of recent similar experiments. Finally, two prototypes are described, including their design requirements and data from prototype testing. The results of the testing are briefly discussed, and next steps are outlined with the goal of developing a low-cost, in-situ microbial water quality sensor using fluorescence spectroscopy principles.

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Nam, Kijin. „Optimization of paths and locations of water quality monitoring systems in surface water environments“. Diss., Atlanta, Ga. : Georgia Institute of Technology, 2008. http://hdl.handle.net/1853/24745.

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Thesis (Ph.D.)--Civil and Environmental Engineering, Georgia Institute of Technology, 2009.
Committee Chair: Aral, Mustafa; Committee Member: Guan, Jiabao; Committee Member: Kim, Seong-Hee; Committee Member: Roberts, Philip; Committee Member: Uzer, Turgay.

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Kwong, Pui-ki, und 鄺沛琪. „Surface water quality indicators in China and their implications for sustainability“. Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2006. http://hub.hku.hk/bib/B36618718.

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Heller, Winfried. „Hydro-dynamic effects with particular consideration of water quality and their measurement methods“. Doctoral thesis, Tönning; Lübeck; Marburg : Der Andere Verl, 2005. http://deposit.ddb.de/cgi-bin/dokserv?idn=979397405.

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Heller, Winfried. „Hydro-dynamic Effects with Particular Consideration of Water Quality and their Measurement Methods“. Doctoral thesis, Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2006. http://nbn-resolving.de/urn:nbn:de:swb:14-1141217614058-76453.

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Die Entwicklung der Strömungsmechanik im 20. Jahrhundert wurde auch durch intensive Forschungen geprägt, um die zahlreichen in der Praxis auftretenden hydrodynamischen Effekte zu ergründen, die physikalischen Abläufe und Zusammenhänge zu verstehen und diese mathematisch zu beschreiben. Dies wurde notwendig, da mit den hydrodynamischen Grundgleichungen allein keine Beschreibung der aus den Fluideigenschaften resultierenden Erscheinungen in Flüssigkeitsströmungen möglich war. Um die Qualität der Flüssigkeiten bezüglich ihres Gasgehaltes und ihrer Keimverteilung beurteilen zu können, wurden mit Beginn des 20. Jahrhunderts unterschiedliche Messmethoden und Apparaturen entwickelt und gebaut. Diese Entwicklung ließ sich annähernd vollständig darstellen, hierbei besonders die Entwicklungen von Apparaturen zur Bestimmung des Gesamtgasgehaltes. Neben der zumeist schwierigen Handhabung dieser Messgeräte und Methoden wird dabei nur der Einfluss einzelner Messgrößen, wie Gesamtgasgehalt, Gelöstsauerstoffgehalt, Keimgehalt, Keimverteilung und Keimgrößenverteilung auf hydrodynamische Effekte untersucht. Die aber in realen Strömungen auftretenden Wechselwirkungen zwischen den Einflussgrößen werden nicht berücksichtigt. Schon am Ende des 19. Jahrhundert begann die Entwicklung von Geräten und Methoden zur Bestimmung von Zugspannungen in Flüssigkeiten. Den anfänglich statischen Methoden folgten mit Beginn der 70-er Jahre des 20. Jahrhunderts die bis heute andauernden Entwicklungen dynamischer Methoden. Während für speziell behandelte Flüssigkeiten unter statischen Bedingungen Zugspannungen von einigen hundert bar gemessen wurden, liegen die typischen Werte für Wasser mit der Wirbel- oder Dralldüse gemessen, zwischen null und zwei bar. Das zeigt den starken Einfluss der Wechselwirkungen aller Einflussgrößen auf die Zugspannung in strömenden Flüssigkeiten. Außer auf die Schallgeschwindigkeit und die Druckverteilung an Profilen hat die Wasserqualität einen besonders starken Einfluss auf bestimmte Kavitationserscheinungen. Weltweite Kavitationstests zeigten, dass ohne Bestimmung der aktuellen Zugspannung des Testwassers keine reproduzierbaren Ergebnisse bezüglich des Kavitationsbeginns möglich sind. Bei Untersuchungen zur Kavitationserosion wurde der Zusammenhang zwischen Wasserqualität und erosiver Aggressivität und Erosionsrate eindeutig nachgewiesen. Die permanente Messung der Zugspannung der Testflüssigkeit ist bei Kavitationsexperimenten an Modellkörpern offensichtlich zwingend notwendig, um die Messergebnisse korrekt interpretieren zu können. Kavitationserscheinungen an Profilen oder Durchströmteilen bewirken Änderungen von Auftriebs-, Widerstands- und Verlustbeiwerten in Abhängigkeit vom Fortschrittsgrad der Kavitation. Hierbei spielen die Beeinflussung der Transition, Ablösung, Versperrung und Druckverteilung eine besondere Rolle. Bei elektrisch leitfähigen Fluiden ist die Qualität durch die Leitfähigkeit bestimmt. Mittels elektromagnetischer Felder werden Lorentzkräfte erzeugt, deren Wirkung sich zeigt in der Unterdrückung von Strömungsablösung, Widerstandsverringerung und stärkerem Auftrieb. Vielfältige experimentelle Forschungsergebnisse auf dem Gebiet der Strömungsmechanik haben gezeigt, dass für die Beschreibung realer Strömungsvorgänge die Qualität des Fluides berücksichtigt werden muss. Da die vielen Einflussgrößen in der Strömung permanenten Wechselwirkungen unterliegen, führt letztlich die Summe aller Einzeleinflüsse auf die genannten Effekte. Für die Bestimmung der Wasserqualität z.B. bei Kavitationsexperimenten kann die Zugspannung des Testwassers gemessen werden, wodurch die genauere mathematische Beschreibung des Kavitationsbeginns möglich wird
The development of fluid mechanics during the twentieth century has been affected by intense research in order to fathom numerous practically relevant hydrodynamic effects, to understand the physical processes and correlations and to describe them mathematically. This became necessary because employing only the fundamental hydrodynamic equations, the description of certain phenomena in fluid flows caused by fluid properties was impossible. In order to assess the quality of fluids regarding their gas contents and their nuclei distributions, various measuring methods and devices have been developed and constructed since the beginning of the twentieth century. This historical development could be described nearly completely in this work, particularly the development of devices to determine the total gas content. Apart from the mostly difficult handling of these measurement methods and devices, only the influence of single parameters such as the total gas content, the dissolved oxygen content, nucleus content, nucleus distribution and the distribution of nucleus sizes on hydrodynamic effects was examined. However, the correlations between these single parameters, as they occur in real flows, could not be taken into consideration. As early as the end of the ninetieth century the development of methods and devices began to determine the tensile strength of fluids. The initially static methods have been followed by the developments of dynamic methods since the beginning of the 1970s. While for specially prepared fluids, tensile strengths of several hundred bar were measured under static conditions, the typical values for water, measured with the eddy and swirl nozzle, range between zero and two bar. This illustrates the strong influence of interactions between all parameters on the tensile strength in flowing fluids. Except for sound velocity and pressure distribution at profiles, water quality particularly affects certain cavitation phenomena. Various cavitation tests around the world have shown that without determining the actual tensile strength of the test water, it is impossible to obtain reproducible results regarding cavitation inception. In experiments concerning cavitation erosion, the correlation between water quality, erosive aggressiveness and erosion rate was proven unmistakably. Evidently, permanent measurement of the test fluid?s tensile stress during cavitation experiments with model bodies is compulsory in order to be able to interpret measurement results correctly. Cavitation phenomena at profiles or other parts affected by flow cause changes of lift, drag and loss coefficients depending on the degree of the cavitation progress. The influence of transition, detachment, obstruction and pressure distribution plays a special role. The quality of electrically conductive fluids is determined by their conductivity. By means of electromagnetic fields Lorentz-forces are generated, whose effect can be observed in lessening of flow detachment, drag reduction and increased lift. Manifold experimental research results in the area of fluid mechanics have proven that the fluid quality must be taken into account when describing real flow processes. Since the many flow parameters are subject to permanent interaction, ultimately, the sum of all single parameters lead to the effects mentioned. For the determination of the water quality such as in cavitation experiments, the tensile stress of the water can be measured making the mathematical description of cavitation inception possible. - (The German online version of this thesis for qualification as university teacher has been published under the titel "Hydrodynamische Effekte unter besonderer Berücksichtigung der Wasserqualität und ihre Messverfahren" - http://hsss.slub-dresden.de/hsss/servlet/hsss.urlmapping.MappingServlet?id=1141215758714-7391)

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岑永昌 und Wing-cheong Sham. „The determination of mercury in sediment, river water and seawater samples, and the determination of Cr(VI) in river water“. Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 1991. http://hub.hku.hk/bib/B31210533.

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Bücher zum Thema "Water quality – Eurasia – Measurement"

Association, American Water Works, Hrsg. Water quality. 4. Aufl. Denver, Colo: American Water Works Association, 2010.

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Ritter, Joseph A. Water quality. 4. Aufl. Denver, Colo: American Water Works Association, 2010.

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Mackenzie River Basin Committee (Canada) und Canada. Inland Waters Directorate. Water Quality Branch., Hrsg. Water quality. Regina, Sask: Water Quality Branch, Inland Waters Directorate, Environment Canada, 1985.

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Association, American Water Works, Hrsg. Water quality. 3. Aufl. [Denver Colo.]: American Water Works Association, 2003.

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Organization, World Meteorological, Hrsg. Manual on water-quality monitoring. Geneva, Switzerland: Secretariat of the World Meteorological Organization, 1988.

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Duerring, Christine L. Nantucket Harbor water quality survey: Water quality survey data, summary of significant findings, 1988. Westborough, Mass: Massachusetts Dept. of Environmental Protection, Division of Water Pollution Control, Technical Services Branch, 1990.

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Baczynski, Robert J. 1990 ambient water quality monitoring results. Concord, N.H. (6 Hazen Dr., P.O. Box 95, Concord 03302-0095): The Division, 1991.

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C, Loftis Jim, und McBride Graham B. 1948-, Hrsg. Design of water quality monitoring systems. New York: Van Nostrand Reinhold Co., 1990.

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K, Mueller David, Nowell Lisa H, Geological Survey (U.S.) und National Water-Quality Assessment Program (U.S.), Hrsg. Methods for comparing water-quality conditions among National Water-Quality Assessment Study units, 1992-1995. Sacramento, Calif: U.S. Dept. of the Interior, U.S. Geological Survey, 1998.

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Barbie, Dana L. Ground-water withdrawals, water levels, and ground-water quality in the Houston district, Texas, with emphasis on 1985-89. Austin, Tex: U.S Geological Survey, 1993.

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Buchteile zum Thema "Water quality – Eurasia – Measurement"

Boyd, Claude E., und Craig S. Tucker. „Measurement of Water Quality“. In Pond Aquaculture Water Quality Management, 576–600. Boston, MA: Springer US, 1998. http://dx.doi.org/10.1007/978-1-4615-5407-3_15.

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Reznikova, Tais, Shynar Sarikenova und Ruslan Melian. „Harmonization of Water Quality Legislation in Shared Basins of Central Asia“. In Water, Energy and Environment in Eurasia, 223–48. Nevşehir: Cappadocia University Press, 2022. http://dx.doi.org/10.35250/kun/9786054448227.8.

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Perrier, E. R., und A. B. Salkini. „Water Quality, Irrigation Measurement and Efficiency“. In Supplemental Irrigation in the Near East and North Africa, 177–89. Dordrecht: Springer Netherlands, 1991. http://dx.doi.org/10.1007/978-94-011-3766-9_12.

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Renger, E. „Measurement of Suspended Loads in Streams by Means of Hydrocyclones“. In Estuarine Water Quality Management, 239–42. Berlin, Heidelberg: Springer Berlin Heidelberg, 1990. http://dx.doi.org/10.1007/978-3-642-75413-5_36.

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Knutz, T., P. Koske und J. Rathlev. „Current Measurement in Estuaries by Electro-Magnetic Methods and DECCA-Drifters“. In Estuarine Water Quality Management, 217–20. Berlin, Heidelberg: Springer Berlin Heidelberg, 1990. http://dx.doi.org/10.1007/978-3-642-75413-5_31.

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Cerdà, V., J. Avivar, L. Ferrer und L. O. Leal. „Automatic Water and Wastewater Quality Monitoring Systems“. In Smart Sensors, Measurement and Instrumentation, 105–23. Berlin, Heidelberg: Springer Berlin Heidelberg, 2013. http://dx.doi.org/10.1007/978-3-642-37006-9_5.

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Sam, Ajin Mathew, und C. Balaji. „Reconfigurable WSN Interface for Water Quality Measurement“. In Advances in Intelligent Systems and Computing, 1279–85. New Delhi: Springer India, 2016. http://dx.doi.org/10.1007/978-81-322-2656-7_116.

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Li, D., und S. Liu. „Remote Monitoring of Water Quality for Intensive Fish Culture“. In Smart Sensors, Measurement and Instrumentation, 217–38. Berlin, Heidelberg: Springer Berlin Heidelberg, 2013. http://dx.doi.org/10.1007/978-3-642-37006-9_10.

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Honikel, K. O., und R. Hamm. „Measurement of water-holding capacity and juiciness“. In Quality Attributes and their Measurement in Meat, Poultry and Fish Products, 125–61. Boston, MA: Springer US, 1994. http://dx.doi.org/10.1007/978-1-4615-2167-9_5.

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Cleary, J., D. Maher und D. Diamond. „Development and Deployment of a Microfluidic Platform for Water Quality Monitoring“. In Smart Sensors, Measurement and Instrumentation, 125–48. Berlin, Heidelberg: Springer Berlin Heidelberg, 2013. http://dx.doi.org/10.1007/978-3-642-37006-9_6.

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Konferenzberichte zum Thema "Water quality – Eurasia – Measurement"

Styrin, Evgeny, und Natalya Dmitrieva. „Information Services Quality Measurement“. In EGOSE '15: Challenges in Eurasia. New York, NY, USA: ACM, 2015. http://dx.doi.org/10.1145/2846012.2846023.

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Lai, Yung-Chang, Chien-Chi Kao, Jhih-Dao Jhan, Fei-Hua Kuo, Chih-Wei Chang und Tai-Chueh Shih. „Quality of Service Measurement and Prediction through AI Technology“. In 2020 IEEE Eurasia Conference on IOT, Communication and Engineering (ECICE). IEEE, 2020. http://dx.doi.org/10.1109/ecice50847.2020.9302008.

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Chang, Chin-Chih, Chi-Hung Wei, Min-Tien Lin und Sz-Chwun John Hwang. „Machine Learning Approach to IoT- Based Water Quality Monitoring“. In 2023 IEEE 5th Eurasia Conference on Biomedical Engineering, Healthcare and Sustainability (ECBIOS). IEEE, 2023. http://dx.doi.org/10.1109/ecbios57802.2023.10218420.

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Wiryasaputra, Rita, Chin-Yin Huang, Yu-Wei Chen und Chao-Tung Yang. „Monitoring and Prediction Model of Drinking-Water Quality Based on IoT Architecture“. In 2023 IEEE 5th Eurasia Conference on IOT, Communication and Engineering (ECICE). IEEE, 2023. http://dx.doi.org/10.1109/ecice59523.2023.10383028.

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Peixeiro, R., O. Postolache und Jose Miguel Dias Pereira. „Virtual instrument for water quality parameters measurement“. In 2012 International Conference and Exposition on Electrical and Power Engineering (EPE). IEEE, 2012. http://dx.doi.org/10.1109/icepe.2012.6463829.

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Yang, Ming. „Challenges for Water Quality Measurement for Produced Water Handling Subsea“. In Offshore Technology Conference. Offshore Technology Conference, 2012. http://dx.doi.org/10.4043/23099-ms.

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Konyha, Jozsef. „Grid-based wide area water quality measurement system for surface water“. In 2016 17th International Carpathian Control Conference (ICCC). IEEE, 2016. http://dx.doi.org/10.1109/carpathiancc.2016.7501120.

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Nayeem, Huzaifa, Azeemuddin Syed und Md Zafar Ali Khan. „Low Cost Wavelength Specific Water Quality Measurement Technique“. In 2019 41st Annual International Conference of the IEEE Engineering in Medicine & Biology Society (EMBC). IEEE, 2019. http://dx.doi.org/10.1109/embc.2019.8857381.

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Mat Jafri, Mohammad Z., Khiruddin Abdullah, Mohammed N. Abu Bakar und Stephen Marshall. „Multispectral back-scattering spectrometer for water quality measurement“. In AeroSense 2002, herausgegeben von Xavier P. Maldague und Andres E. Rozlosnik. SPIE, 2002. http://dx.doi.org/10.1117/12.459571.

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fneer, M., J. Kurata, W. J. O. Boyle und K. T. V. Grattan. „Optical Fiber Ammonia Sensor For Water Quality Measurement“. In Optical Fiber Sensors. Washington, D.C.: OSA, 1996. http://dx.doi.org/10.1364/ofs.1996.th35.

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Berichte der Organisationen zum Thema "Water quality – Eurasia – Measurement"

Pickering, Robert, Kathleen Onorevole, Rob Greenwood und Sarah Shadid. Measurement science roadmap workshop for water use efficiency and water quality in premise plumbing systems, August 1-2, 2018:. Gaithersburg, MD: National Institute of Standards and Technology, Dezember 2018. http://dx.doi.org/10.6028/nist.gcr.19-020.

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Bradford, Joe, Itzhak Shainberg und Lloyd Norton. Effect of Soil Properties and Water Quality on Concentrated Flow Erosion (Rills, Ephermal Gullies and Pipes). United States Department of Agriculture, November 1996. http://dx.doi.org/10.32747/1996.7613040.bard.

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Concentrated flow erosion in rills, pipes, ephermal gullies, and gullies is a major contributor of downstream sedimentation. When rill or gullies form in a landscape, a 3- to 5-fold increase in soil loss commonly occurs. The balance between the erosive power of the flow and the erosion resistance of the bed material determines the rate of concentrated flow erosion. The resistance of the bed material to detachment depends primarily on the magnitude of the interparticle forces or cohesion holding the particles and aggregates together. The effect of soil properties on bed material resistance and concentrated flow erosion was evaluated both in the laboratory and field. Both rill erodibility and critical hydraulic shear were greater when measured in 9.0 m long rills under field conditions compared with laboratory mini-flumes. A greater hydraulic shear was required to initiate erosion in the field compared to the mini-flume because of the greater aggregate and clod size and stability. Once erosion was initiated, however, the rate of erosion as a function of hydraulic shear was greater under field conditions because of the greater potential for slaking upon wetting and the greater soil surface area exposed to hydraulic shear. Erosion tests under controlled laboratory conditions with the mini-flume allowed individual soil variables to be studied. Attempts to relate rill erosion to a group soil properties had limited success. When individual soil properties were isolated and studied separately or grouped separately, some trends were identified. For example, the effect of organic carbon on rill erodibility was high in kaolinitic soils, low in smectitic soils, and intermediate in the soils dominated by illite. Slow prewetting and aging increased the cohesion forces between soil particles and decreased rill erodibility. Quick prewetting increased aggregate slaking and increased erodibility. The magnitude of the effect of aging depended upon soil type. The effect of clay mineralogy was evaluated on sand/clay mixtures with montmorillonite (M), Illite (I), and kaolinite (K) clays. Montmorillonite/sand mixtures were much less erodible than either illite or kaolonite sand mixtures. Na-I and Na-K sand mixtures were more erodible than Ca-I and Ca-K due to increased strength from ionic bonding and suppression of repulsive charges by Ca. Na-M was less erodiblethan Ca-M due to increased surface resulting from the accessibility of internal surfaces due to Na saturation. Erodibility decreased when salt concentration was high enough to cause flocculation. This occurred between 0.001 mole L-1 and 0.01 mole L-1. Measuring rill erodibility in mini-flumes enables the measurement of cohesive forces between particles and enhances our ability to learn more about cohesive forces resisting soil detachment under concentrated water flow.

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Starkey, Eric, Daniel McCay, Chrisopher Cooper und Mark Hynds. Assessment of estuarine water and sediment quality at Cape Hatteras National Seashore and Cape Lookout National Seashore: 2021 data summary. National Park Service, Oktober 2022. http://dx.doi.org/10.36967/2294854.

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In July 2021 the Southeast Coast Network conducted an assessment of water quality in the vicinity of Cape Hatteras and Cape Lookout National Seashores as part of the National Park Service Vital Signs Monitoring Program. Monitoring was conducted following methods developed by the Environmental Protection Agency (EPA) as part of the National Coastal Assessment Program (EPA 2010). Laboratory analysis measured chlorophyll a and total and dissolved concentrations of nitrogen and phosphorous. Field measurements included water temperature, pH, dissolved oxygen, and salinity. Water clarity, which requires a Secchi depth measurement, was obtained when possible. All measured parameters were rated as good, fair, or poor based on thresholds set by the EPA (2012). All measured parameters were rated as good, fair, or poor based on thresholds set by the EPA (2012). Water clarity was not calculated at all sites due to the shallow depth of the water in the sound. Of the sites where water clarity could be assessed (5 sites), four measured good and one fair. Sites that were too shallow to measure water clarity had water column conditions that did not preclude light from penetrating to the bottom of the water body so no ecological effects would be expected.Turbidity measurements ranged from 1.0 to 8.0 FNU (Formazin Nephelometric Units) and are good (i.e. < 25 NTU [Nephelometric Turbidity Units]) according to North Carolina Standards (NC Administrative Code 2019). Note that turbidity units of FNU and NTU are roughly equivalent. Chlorophyll a concentration was rated good at 29 sites (97%), and fair at one site (3%). Dissolved inorganic nitrogen (DIN) concentration was good at all 30 sites (100%). Dissolved inorganic phosphorus (DIP) concentration was good at all 30 sites (100%). Dissolved oxygen concentration (bottom) was rated good at all 30 sites (100%). A water-quality condition summary index was calculated for each site sampled at Cape Hatteras and Cape Lookout National Seashores based on the categorical assessments of chlorophyll a, DIN and DIP concentrations, dissolved oxygen, and water clarity. This summary index indicated good water-quality conditions at all thirty sites (100%). Based on the summary water-quality index rating, overall water-quality conditions at Cape Hatteras and Cape Lookout National Seashores during sampling in 2021 were good. For sediment, ecological condition was ranked as good at 30 sites (100%). As a result, no adverse impacts to benthic organisms due to sediment contamination are anticipated at any of the sampled sites. This ranking was assigned according to the 2010 Environmental Protection Agency, National Coastal Condition Assessment (NCCA) thresholds for sediment chemistry.

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Raymond, Kara, Laura Palacios und Evan Gwilliam. Status of climate and water resources at Big Bend National Park: Water year 2019. Herausgegeben von Tani Hubbard. National Park Service, September 2022. http://dx.doi.org/10.36967/2294267.

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Climate and hydrology are major drivers of ecosystem structure and function, particularly in arid and semi-arid ecosystems. Understanding changes in climate, groundwater, streamflow, and water quality is central to assessing the condition of park resources. This report combines data collected on climate, groundwater, and springs at Big Bend National Park (NP) to provide an integrated look at climate and water conditions during water year (WY) 2019 (October 2018–September 2019). However, this report does not address the Rio Grande or its tributaries. Annual precipitation was higher than normal (1981–2010) for Big Bend NP at four of the five National Oceanic and Atmospheric Administration Cooperative Observer Program weather stations: 111% of normal for Chisos Basin, 122% of normal for Panther Junction, 155% of normal for Persimmon Gap, and 124% of normal for Rio Grande Village. Castolon had 88% of normal annual precipitation. All five stations had higher than normal rainfall in October and December, while rainfall totals were substantially below normal at all stations in November, February, and March. Monthly precipitation totals for April through September were more variable from station to station. Mean monthly maximum air temperatures were below normal in the fall months, with Panther Junction as much as 7.5°F below normal in October. Monthly temperatures from January through July were more variable. Temperatures in August and September were warmer than normal at every station, up to +9.4°F at Rio Grande Village and +8.7°F at Chisos Basin in July. The reconnaissance drought index values indicate generally wetter conditions (based on precipitation and evaporative demand) at Chisos Basin since WY2016 and at Panther Junction and Persimmon Gap since WY2015, except for WY2017. This report presents the manual and automatic groundwater monitoring results at nine wells. Five wells had their highest water level in or just before WY2019: Panther Junction #10 peaked at 99.94 ft below ground surface (bgs) in September 2018, Contractor’s Well peaked at 31.43 ft bgs in November 2018, T-3 peaked at 65.39 ft bgs in December 2018, K-Bar #6 Observation Well peaked at 77.78 ft bgs in February 2019, and K-Bar #7 Observation Well peaked at 43.18 ft bgs in February 2019. This was likely in response to above normal rainfall in the later summer and fall 2018. The other monitoring wells did not directly track within-season precipitation. The last measurement at Gallery Well in WY2019 was 18.60 ft bgs. Gallery Well is located 120 feet from the river and closely tracked the Rio Grande stage, generally increasing in late summer or early fall following higher flow events. Water levels in Gambusia Well were consistently very shallow, though the manual well measurement collected in April was 4.25 ft bgs—relatively high for the monitoring record—and occurred outside the normal peak period of later summer and early fall. The last manual measurement taken at TH-10 in WY2019 was 34.80 ft bgs, only 0.45 ft higher than the earliest measurement in 1967, consistent with the lack of directional change in groundwater at this location, and apparently decoupled from within-season precipitation patterns. The last water level reading in WY2019 at Oak Springs #1 was 59.91 ft bgs, indicating an overall decrease of 26.08 ft since the well was dug in 1989. The Southwest Network Collaboration (SWNC) collects data on sentinel springs annually in the late winter and early spring following the network springs monitoring protocol. In WY2019, 18 sentinel site springs were visited at Big Bend NP (February 21, 2019–March 09, 2019). Most springs had relatively few indications of natural and anthropogenic disturbances. Natural disturbances included recent flooding, drying, and wildlife use. Anthropogenic disturbances included flow modifications (e.g., springboxes), hiking trails, and contemporary human use. Crews observed one to seven facultative/obligate wetland plant...

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Adam, Isabelle, Mihály Fazekas, Alfredo Hernandez Sanchez, Peter Horn und Nóra Regös. Integrity Dividends: Procurement in the Water and Sanitation Sector in Latin America and the Caribbean. Herausgegeben von Marcello Basani und Jacopo Gamba. Inter-American Development Bank, Januar 2023. http://dx.doi.org/10.18235/0004688.

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Public procurement represents a large portion of government expenditure, more so in developing economies. Inefficiencies in public expenditures thus place a heavy burden on society. The Water and Sanitation (W&S) sector is especially vulnerable to public procurement inefficiencies due to the capital-intensive and complex nature of large-scale projects such as sewage, pipelines, and general maintenance. Recent studies have found that quality of corporate governance and transparency of water utilities as well as regulatory and supervisory agencies are key drivers of the sectors performance. To support better policies in the W&S sector, this report conducts a sectoral measurement of public procurement integrity using government administrative data and identifies effective interventions for improving the performance of utilities. The following questions are explored: Which types of integrity risk carry the highest economic costs? What are effective policy solutions? Which address the most impactful risks effectively? What are the price savings and project-delay-reducing impacts of such solutions? To this effect, the study analyzes data for six countries in the Latin American & Caribbean region. Several regression models were run to assess which indicators of integrity are good predictors of improved outcomes in terms of price (unit or relative) and quality (delays) of public purchases in the sector.

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Glass, Samuel V., Samuel L. Zelinka, Charles R. Boardman und Emil Engelund Thybring. Promoting advances in understanding water vapor sorption in wood: relegating popular models and misconceptions. Department of the Built Environment, 2023. http://dx.doi.org/10.54337/aau541615744.

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Water vapor sorption is a fundamental characteristic of wood as a building material. Apart from empirical prediction, models are often used to interpret the time-dependent process of water vapor uptake (sorption kinetics) and equilibrium states of water in wood (sorption isotherms). This paper summarizes our recent investigations into measurement methods and popular models that are widely used for interpreting these physical phenomena. Commonly used criteria for determining equilibrium moisture content with the dynamic vapor sorption technique yield much larger errors than previously thought. A more rigorous equilibrium criterion and a method to reduce data acquisition time are proposed. Evaluation of the parallel exponential kinetics model with improved data and multi-exponential decay analysis indicates that this model is unable to characterize the full sorption kinetic response following a step change in relative humidity. Fitting of common sorption isotherm models to high-quality equilibrium data for wood gives model predicted physical quantities such as monolayer capacity and enthalpy of sorption that are far from agreement with independently measured data. Thus, these models are not valid for water vapor sorption in wood. New theoretical models are needed that correctly describe the physical phenomena.

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Castellano, Mike J., Abraham G. Shaviv, Raphael Linker und Matt Liebman. Improving nitrogen availability indicators by emphasizing correlations between gross nitrogen mineralization and the quality and quantity of labile soil organic matter fractions. United States Department of Agriculture, Januar 2012. http://dx.doi.org/10.32747/2012.7597926.bard.

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A major goal in Israeli and U.S. agroecosystems is to maximize nitrogen availability to crops while minimizing nitrogen losses to air and water resources. This goal has presented a significant challenge to global agronomists and scientists because crops require large inputs of nitrogen (N) fertilizer to maximize yield, but N fertilizers are easily lost to surrounding ecosystems where they contribute to water pollution and greenhouse gas concentrations. Determination of the optimum N fertilizer input is complex because the amount of N produced from soil organic matter varies with time, space and management. Indicators of soil N availability may help to guide requirements for N fertilizer inputs and are increasingly viewed as indicators of soil health To address these challenges and improve N availability indicators, project 4550 “Improving nitrogen availability indicators by emphasizing correlations between gross nitrogen mineralization and the quality and quantity of labile organic matter fractions” addressed the following objectives: Link the quantity and quality of labile soil organic matter fractions to indicators of soil fertility and environmental quality including: i) laboratory potential net N mineralization ii) in situ gross N mineralization iii) in situ N accumulation on ion exchange resins iv) crop uptake of N from mineralized soil organic matter sources (non-fertilizer N), and v) soil nitrate pool size. Evaluate and compare the potential for hot water extractable organic matter (HWEOM) and particulate organic matter quantity and quality to characterize soil N dynamics in biophysically variable Israeli and U.S. agroecosystems that are managed with different N fertility sources. Ultimately, we sought to determine if nitrogen availability indicators are the same for i) gross vs. potential net N mineralization processes, ii) diverse agroecosystems (Israel vs. US) and, iii) management strategies (organic vs. inorganic N fertility sources). Nitrogen availability indicators significantly differed for gross vs. potential N mineralization processes. These results highlight that different mechanisms control each process. Although most research on N availability indicators focuses on potential net N mineralization, new research highlights that gross N mineralization may better reflect plant N availability. Results from this project identify the use of ion exchange resin (IERs) beads as a potential technical advance to improve N mineralization assays and predictors of N availability. The IERs mimic the rhizosphere by protecting mineralized N from loss and immobilization. As a result, the IERs may save time and money by providing a measurement of N mineralization that is more similar to the costly and time consuming measurement of gross N mineralization. In further search of more accurate and cost-effective predictors of N dynamics, Excitation- Emission Matrix (EEM) spectroscopy analysis of HWEOM solution has the potential to provide reliable indicators for changes in HWEOM over time. These results demonstrated that conventional methods of labile soil organic matter quantity (HWEOM) coupled with new analyses (EEM) may be used to obtain more detailed information about N dynamics. Across Israeli and US soils with organic and inorganic based N fertility sources, multiple linear regression models were developed to predict gross and potential N mineralization. The use of N availability indicators is increasing as they are incorporated into soil health assessments and agroecosystem models that guide N inputs. Results from this project suggest that some soil variables can universally predict these important ecosystem process across diverse soils, climate and agronomic management. BARD Report - Project4550 Page 2 of 249

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Minz, Dror, Stefan J. Green, Noa Sela, Yitzhak Hadar, Janet Jansson und Steven Lindow. Soil and rhizosphere microbiome response to treated waste water irrigation. United States Department of Agriculture, Januar 2013. http://dx.doi.org/10.32747/2013.7598153.bard.

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Research objectives : Identify genetic potential and community structure of soil and rhizosphere microbial community structure as affected by treated wastewater (TWW) irrigation. This objective was achieved through the examination soil and rhizosphere microbial communities of plants irrigated with fresh water (FW) and TWW. Genomic DNA extracted from soil and rhizosphere samples (Minz laboratory) was processed for DNA-based shotgun metagenome sequencing (Green laboratory). High-throughput bioinformatics was performed to compare both taxonomic and functional gene (and pathway) differences between sample types (treatment and location). Identify metabolic pathways induced or repressed by TWW irrigation. To accomplish this objective, shotgun metatranscriptome (RNA-based) sequencing was performed. Expressed genes and pathways were compared to identify significantly differentially expressed features between rhizosphere communities of plants irrigated with FW and TWW. Identify microbial gene functions and pathways affected by TWW irrigation*. To accomplish this objective, we will perform a metaproteome comparison between rhizosphere communities of plants irrigated with FW and TWW and selected soil microbial activities. Integration and evaluation of microbial community function in relation to its structure and genetic potential, and to infer the in situ physiology and function of microbial communities in soil and rhizospere under FW and TWW irrigation regimes. This objective is ongoing due to the need for extensive bioinformatics analysis. As a result of the capabilities of the new PI, we have also been characterizing the transcriptome of the plant roots as affected by the TWW irrigation and comparing the function of the plants to that of the microbiome. *This original objective was not achieved in the course of this study due to technical issues, especially the need to replace the American PIs during the project. However, the fact we were able to analyze more than one plant system as a result of the abilities of the new American PI strengthened the power of the conclusions derived from studies for the 1ˢᵗ and 2ⁿᵈ objectives. Background: As the world population grows, more urban waste is discharged to the environment, and fresh water sources are being polluted. Developing and industrial countries are increasing the use of wastewater and treated wastewater (TWW) for agriculture practice, thus turning the waste product into a valuable resource. Wastewater supplies a year- round reliable source of nutrient-rich water. Despite continuing enhancements in TWW quality, TWW irrigation can still result in unexplained and undesirable effects on crops. In part, these undesirable effects may be attributed to, among other factors, to the effects of TWW on the plant microbiome. Previous studies, including our own, have presented the TWW effect on soil microbial activity and community composition. To the best of our knowledge, however, no comprehensive study yet has been conducted on the microbial population associated BARD Report - Project 4662 Page 2 of 16 BARD Report - Project 4662 Page 3 of 16 with plant roots irrigated with TWW – a critical information gap. In this work, we characterize the effect of TWW irrigation on root-associated microbial community structure and function by using the most innovative tools available in analyzing bacterial community- a combination of microbial marker gene amplicon sequencing, microbial shotunmetagenomics (DNA-based total community and gene content characterization), microbial metatranscriptomics (RNA-based total community and gene content characterization), and plant host transcriptome response. At the core of this research, a mesocosm experiment was conducted to study and characterize the effect of TWW irrigation on tomato and lettuce plants. A focus of this study was on the plant roots, their associated microbial communities, and on the functional activities of plant root-associated microbial communities. We have found that TWW irrigation changes both the soil and root microbial community composition, and that the shift in the plant root microbiome associated with different irrigation was as significant as the changes caused by the plant host or soil type. The change in microbial community structure was accompanied by changes in the microbial community-wide functional potential (i.e., gene content of the entire microbial community, as determined through shotgun metagenome sequencing). The relative abundance of many genes was significantly different in TWW irrigated root microbiome relative to FW-irrigated root microbial communities. For example, the relative abundance of genes encoding for transporters increased in TWW-irrigated roots increased relative to FW-irrigated roots. Similarly, the relative abundance of genes linked to potassium efflux, respiratory systems and nitrogen metabolism were elevated in TWW irrigated roots when compared to FW-irrigated roots. The increased relative abundance of denitrifying genes in TWW systems relative FW systems, suggests that TWW-irrigated roots are more anaerobic compare to FW irrigated root. These gene functional data are consistent with geochemical measurements made from these systems. Specifically, the TWW irrigated soils had higher pH, total organic compound (TOC), sodium, potassium and electric conductivity values in comparison to FW soils. Thus, the root microbiome genetic functional potential can be correlated with pH, TOC and EC values and these factors must take part in the shaping the root microbiome. The expressed functions, as found by the metatranscriptome analysis, revealed many genes that increase in TWW-irrigated plant root microbial population relative to those in the FW-irrigated plants. The most substantial (and significant) were sodium-proton antiporters and Na(+)-translocatingNADH-quinoneoxidoreductase (NQR). The latter protein uses the cell respiratory machinery to harness redox force and convert the energy for efflux of sodium. As the roots and their microbiomes are exposed to the same environmental conditions, it was previously hypothesized that understanding the soil and rhizospheremicrobiome response will shed light on natural processes in these niches. This study demonstrate how newly available tools can better define complex processes and their downstream consequences, such as irrigation with water from different qualities, and to identify primary cues sensed by the plant host irrigated with TWW. From an agricultural perspective, many common practices are complicated processes with many ‘moving parts’, and are hard to characterize and predict. Multiple edaphic and microbial factors are involved, and these can react to many environmental cues. These complex systems are in turn affected by plant growth and exudation, and associated features such as irrigation, fertilization and use of pesticides. However, the combination of shotgun metagenomics, microbial shotgun metatranscriptomics, plant transcriptomics, and physical measurement of soil characteristics provides a mechanism for integrating data from highly complex agricultural systems to eventually provide for plant physiological response prediction and monitoring. BARD Report

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George und Hart. PR-015-06603-R02 Tests of Instruments for Measuring Hydrocarbon Dew Points in Natural Gas Streams Phase 2. Chantilly, Virginia: Pipeline Research Council International, Inc. (PRCI), September 2008. http://dx.doi.org/10.55274/r0010969.

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Research has assessed the accuracy of two commercially-available hydrocarbon dew point (HCDP) analyzers, an Ametek� Model 241 CE II and a Michell Condumax II. During a previous phase of this project, both automated analyzers, along with a Bureau of Mines chilled mirror device serving as a reference, were tested on gravimetrically-prepared gas blends chosen to simulate a transmission-quality gas and a production gas. The measurement repeatability of both units was found to be better than the manual chilled mirror. Trends in the analyzer and manual chilled mirror measurements suggested that differences in performance between the automated units were related to their measurement techniques and default set points. During the second phase of the project, the Ametek and Michell automated analyzers were tested again on the transmission-quality test gas used in Phase 1, but with specific levels of contamination added to gain knowledge of their performance under adverse conditions. In one round of tests, water vapor was added to simulate a transmission gas with water vapor levels above common tariff specifications. In the second round of tests, the test gas contained both methanol and water vapor, simulating a stream to which methanol has been added to prevent hydrates. Contaminants were added to the test gas stream in amounts such that, depending upon the pressure of the test stream, the contaminant dew point would be reached first, the HCDP would be reached first, or the two phases would condense simultaneously. Multiple HCDP measurements were made with the analyzers to determine their ability to accurately measure HCDPs under these adverse conditions. Analyzer results were again compared to HCDP measurements taken with the Bureau of Mines chilled mirror device and a digital video camera. Results were adjusted for small changes in the heavy hydrocarbon content of the test gases over time, using predictions from an equation of state and gas chromatographic analyses of the test gases.

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Zhang, Renduo, und David Russo. Scale-dependency and spatial variability of soil hydraulic properties. United States Department of Agriculture, November 2004. http://dx.doi.org/10.32747/2004.7587220.bard.

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Water resources assessment and protection requires quantitative descriptions of field-scale water flow and contaminant transport through the subsurface, which, in turn, require reliable information about soil hydraulic properties. However, much is still unknown concerning hydraulic properties and flow behavior in heterogeneous soils. Especially, relationships of hydraulic properties changing with measured scales are poorly understood. Soil hydraulic properties are usually measured at a small scale and used for quantifying flow and transport in large scales, which causes misleading results. Therefore, determination of scale-dependent and spatial variability of soil hydraulic properties provides the essential information for quantifying water flow and chemical transport through the subsurface, which are the key processes for detection of potential agricultural/industrial contaminants, reduction of agricultural chemical movement, improvement of soil and water quality, and increase of agricultural productivity. The original research objectives of this project were: 1. to measure soil hydraulic properties at different locations and different scales at large fields; 2. to develop scale-dependent relationships of soil hydraulic properties; and 3. to determine spatial variability and heterogeneity of soil hydraulic properties as a function of measurement scales. The US investigators conducted field and lab experiments to measure soil hydraulic properties at different locations and different scales. Based on the field and lab experiments, a well-structured database of soil physical and hydraulic properties was developed. The database was used to study scale-dependency, spatial variability, and heterogeneity of soil hydraulic properties. An improved method was developed for calculating hydraulic properties based on infiltration data from the disc infiltrometer. Compared with the other methods, the proposed method provided more accurate and stable estimations of the hydraulic conductivity and macroscopic capillary length, using infiltration data collected atshort experiment periods. We also developed scale-dependent relationships of soil hydraulic properties using the fractal and geostatistical characterization. The research effort of the Israeli research team concentrates on tasks along the second objective. The main accomplishment of this effort is that we succeed to derive first-order, upscaled (block effective) conductivity tensor, K'ᵢⱼ, and time-dependent dispersion tensor, D'ᵢⱼ, i,j=1,2,3, for steady-state flow in three-dimensional, partially saturated, heterogeneous formations, for length-scales comparable with those of the formation heterogeneity. Numerical simulations designed to test the applicability of the upscaling methodology to more general situations involving complex, transient flow regimes originating from periodic rain/irrigation events and water uptake by plant roots suggested that even in this complicated case, the upscaling methodology essentially compensated for the loss of sub-grid-scale variations of the velocity field caused by coarse discretization of the flow domain. These results have significant implications with respect to the development of field-scale solute transport models capable of simulating complex real-world scenarios in the subsurface, and, in turn, are essential for the assessment of the threat posed by contamination from agricultural and/or industrial sources.

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