Search results for "River water"
showing 10 items of 21 documents
Analysis of psychoactive substances in water by information dependent acquisition on a hybrid quadrupole time-of-flight mass spectrometer.
2016
Emerging drugs of abuse, belonging to many different chemical classes, are attracting users with promises of “legal” highs and easy access via internet. Prevalence of their consumption and abuse through wastewater-based epidemiology can only be realized if a suitable analytical screening procedure exists to detect and quantify them in water. Solid-phase extraction and ultra-high performance liquid chromatography quadrupole time-of-flight-mass spectrometry (UHPLC–QqTOF–MS/MS) was applied for rapid suspect screening as well as for the quantitative determination of 42 illicit drugs and metabolites in water. Using this platform, we were able to identify amphetamines, tryptamines, piperazines, p…
Immuno-SLM—a combined sample handling and analytical technique
2004
Immuno-supported liquid membrane (immuno-SLM) extraction is a new technique that makes use of antibody (Ab)-antigen interactions as the "extraction force" to drive the mass transfer in a selective way. In immuno-SLM, anti-analyte (Ag) Abs are introduced into the acceptor phase of the SLM unit to trap the Ag that passes from the flowing donor through the SLM into the stagnant acceptor. The amount of immuno-extracted analyte (AbAg) is quantified by connecting the immuno-SLM unit on-line with a non-competitive heterogeneous fluorescence flow immunoassay (FFIA) that makes use of a fluorescein-labeled analyte tracer that titrates the residual excess of Ab present in the acceptor. A restricted ac…
Iron as a source of color in river waters.
2015
Organic chromophores of total organic carbon (TOC) and those of iron (Fe) contribute to the color of water, but the relative contributions of colored organic carbon (COC%) and Fe (Fe%) are poorly known. In this study, we unraveled Fe% and COC% in 6128 unfiltered water samples collected from 94 Finnish river sites of contrasting catchment properties. According to regression analysis focusing on TOC alone, on average 84% of the mean TOC consisted of COC, while 16% was non-colored or below the color-detection limit. COC and Fe were much more important sources of color than phytoplankton (chlorophyll a as a proxy) or non-algal particles (suspended solids as a proxy). When COC and Fe were consid…
Structure and Sensory Analyses of Tainting Substances in Finnish Freshwater Environments
1988
GC/MS/SNIFF/TASTE methods have been used in Finland to identify the causes of three tainting problems in water and one in fish nets. Structure determination was often verified by comparison with authentic compounds. Algal growth was implicated to be the source of geosmin and MIB in river water in Northern Finland and was associated with the appearance of tainting problems in raw water and reservoir water in Åland county. Terpenoids (e.g. camphor), degradation products of natural lipids (e.g. aldehydes, ketones and unsaturated aliphatic compounds) and volatile organohalogen compounds were frequently found in contaminated water but showed minor tainting effects compared to geosmin and MIB. Di…
Reverse electrodialysis
2016
Abstract Reverse electrodialysis (RED) technology has grown significantly in the last decade, gaining a fast increase in its technology readiness level and presenting some interesting examples of RED pilot systems operating under very different real environments. In this chapter, an overview of technological developments and piloting examples are reported. In particular, a short introduction is given on the historical trend of RED technology growth, followed by a careful analysis of which feed solutions can be adopted and how these can affect the process performance, potentials, and applications. Most prominent fluid dynamics aspects for the RED process are presented, highlighting how these…
Analysis and simulation of scale-up potentials in reverse electrodialysis
2015
The Reverse Electrodialysis (RED) process has been widely accepted as a viable and promising technology to produce electric energy from salinity difference (salinity gradient power - e.g. using river water/seawater, or seawater and concentrated brines). Recent R&D efforts demonstrated how an appropriate design of the RED unit and a suitable selection of process conditions may crucially enhance the process performance. With this regard, a process simulator was developed and validated with experimental data collected on a lab-scale unit, providing a new modelling tool for process optimisation. In this work, performed within the REAPower project (www.reapower.eu), a process simulator previousl…
Multiregression Analysis of the Kinetic Constants in Ephemeral Rivers: The Case Study of the Oreto River
2018
Profuse efforts have been committed to develop efficient tools to measure the ecological status of the receiving water body quality state. The recurrence to mathematical models as support tools for the receiving water body quality assessment can be an optimal choice. Indeed, mathematical models can allow to build-up the cause effect relationship between polluting sources and receiving water quality. Regarding the river water quality modelling, two different kinds of river can be single out: large and small rivers. In the modelling approach, the main differences between the two types of river are reflected in the model kinetic constants. Indeed, the main quality processes which control and g…
Spatial distribution and temporal changes in river water temperature in the Baltic States
2017
Abstract The thermal regime of rivers in the Baltic States (Estonia, Latvia and Lithuania) is not sufficiently studied. The presented research describes the spatial distribution and temporal variation of river water temperature (WT) in the Baltic States using a unified methodology. The object of the research is the WT of rivers during the warm season (May–October) and the warmest month of the year (July). The contour maps of WT were compiled for the rivers of the Baltic States using data series for the period 1961–1990 from 17 water measuring stations in Estonia (EST), 36 stations in Latvia (LV) and 40 stations in Lithuania (LT). These maps allow the evaluation of WT for the unmonitored riv…
Water quality modelling for ephemeral rivers: Model development and parameter assessment
2010
Summary River water quality models can be valuable tools for the assessment and management of receiving water body quality. However, such water quality models require accurate model calibration in order to specify model parameters. Reliable model calibration requires an extensive array of water quality data that are generally rare and resource-intensive, both economically and in terms of human resources, to collect. In the case of small rivers, such data are scarce due to the fact that these rivers are generally considered too insignificant, from a practical and economic viewpoint, to justify the investment of such considerable time and resources. As a consequence, the literature contains v…
Assessment of the integrated urban water quality model complexity through identifiability analysis
2010
Urban sources of water pollution have often been cited as the primary cause of poor water quality in receiving water bodies (RWB), and recently many studies have been conducted to investigate both continuous sources, such as wastewater-treatment plant (WWTP) effluents, and intermittent sources, such as combined sewer overflows (CSOs). An urban drainage system must be considered jointly, i.e., by means of an integrated approach. However, although the benefits of an integrated approach have been widely demonstrated, several aspects have prevented its wide application, such as the scarcity of field data for not only the input and output variables but also parameters that govern intermediate st…