Sökning: "Solute retention"

Visar resultat 1 - 5 av 19 avhandlingar innehållade orden Solute retention.

1. 1. Effect of Hyporheic Exchange on Conservative and Reactive Solute Transport in Streams : Model Assessments Based on Tracer Tests

   Författare :Karin Jonsson; Anders Wörman; Bernhard H. Schmid; Uppsala universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Earth sciences; conservative; hyporheic exchange; model; reactive; retention; solute; sorption kinetics; stream transport; temporal moments; tracer experiment; Geovetenskap; Earth sciences; Geovetenskap; Sedimentology; sedimentologi;

   Sammanfattning : Understanding of the processes affecting solute transport in flowing water is important for the possibility to predict the evolution with time of polluted stream systems. This thesis presents tracer experiment methodology and model developments for solute transport in streams, with special focus on retention processes and their effect on solute stream transport. LÄS MER

3. 2. Solute Transport Across Scales : Time Series Analyses of Water Quality Responses to Quantify Retention and Attenuation Mechanisms in Watersheds

   Författare :Joakim Riml; Anders Wörman; Aaron I. Packman; KTH; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Solute transport modeling; Transient storage; Tracer test; Central temporal moments; Spectral analysis; Parameterization;

   Sammanfattning : The intra-continental movement of waterborne contaminants is governed by the distribution of solute load in the landscape along with the characteristics and distribution of the hydrological pathways that transport the solutes. An understanding of the processes affecting the transport and fate of the contaminants is crucial for assessments of solute concentrations and their environmental effect on downstream recipients. LÄS MER

4. 3. The influence of multiscale hyporheic flow on solute transport : Implications for stream restoration enhancing nitrogen removal

   Författare :Ida Morén; Anders Wörman; Joakim Riml; Roy Haggerty; KTH; []
   Nyckelord :LANTBRUKSVETENSKAPER; AGRICULTURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; Hyporheic exchange flow; Hydrological modeling; Solute transport; Stream restoration; Nitrogen; Power spectral analysis; Hydraulic and Hydrologic Engineering; Hydraulik och teknisk hydrologi;

   Sammanfattning : Stream water that flows into and out of streambeds is called hyporheic exchange flow (HEF).It continuously interacts with groundwater and thereby affect the water quality of local streamreaches as well as downstream recipients by providing an environment where solutes andenergy can be retained and degraded. LÄS MER

5. 4. Fundamental Investigations of Adsorption in SFC

   Författare :Emelie Glenne; Torgny Fornstedt; Jörgen Samuelsson; Caroline West; Karlstads universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Supercritical fluid chromatography; SFC; Adsorption isotherm; Excess adsorption isotherm; Solvent adsorption; Peak distortion; Solute retention; Overloaded peaks; Kemi; Chemistry;

   Sammanfattning : In supercritical fluid chromatography (SFC), the eluent is composed by carbon dioxide, often with additional components, in a condition between gas and liquid. This thesis aims to reach a deeper understanding of SFC by revealing the function of the additional eluent components through systematic adsorption studies. LÄS MER

7. 5. Hydrodynamic control of retention in heterogeneous aquifers and fractured rock

   Författare :Hua Cheng; Vladimir Cvetkovic; Chin-Fu Tsang; KTH; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Aquifer; Fracture; groundwater; First-order solution; Monte-Carlo simulation; Nu-clear waste; Heterogeneity; Retention processes; Matrix diffusion; Prediction; Evaluation; Travel time; Flow rate; ; Water engineering; Vattenteknik;

   Sammanfattning : In this thesis, fluid flow and solute transport in heterogeneous aquifers and particularly in frac-tured rock have been investigated using Lagrangian Stochastic Advective-Reaction (LaSAR) framework. The heterogeneity of the aquifer structure or fracture configuration, as well as the various reaction/retention processes have been considered in the modelling approach. LÄS MER