Sökning: "humic substances"

Visar resultat 21 - 25 av 38 avhandlingar innehållade orden humic substances.

1. 21. Bacteria that escape predation : waterborne pathogens and their relatives

   Författare :Karolina I. A. Eriksson; Agneta Andersson; Johanna Thelaus; Jon Ahlinder; David Sundell; Klaus Jürgens; Umeå universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; bacterial pathogens; protozoa; predation resistance; aquatic microbiology; climate change; opportunists; humification; iron; environmental science; miljövetenskap; mikrobiologi; Microbiology;

   Sammanfattning : The hidden presence of opportunistic bacterial pathogens in the environment evokes concerns about emerging diseases, especially in the light of climate change. The co-evolution of bacteria and their predators (protozoa) has led to bacterial defence strategies of which some contribute to the ability of bacteria to cause disease. LÄS MER

3. 22. Capillary electrophoresis and multivariate calibration in the analysis of natural waters

   Författare :Johan Dahlén; Linköpings universitet; []
   Nyckelord :SAMHÄLLSVETENSKAP; SOCIAL SCIENCES; INTERDISCIPLINARY RESEARCH AREAS; TVÄRVETENSKAPLIGA FORSKNINGSOMRÅDEN;

   Sammanfattning : The aim of this work was to explore the applicability of capillary zone electrophoresis (CZE) and multivariate partial least squares (PLS) regression in the analysis of organic compounds and inorganic ions in natural waters. A new CZE application was developed to analyze low molecular weight (LMW) organic acids. LÄS MER

4. 23. Surface complexation in natural particle suspensions

   Författare :Qing Du; Luleå tekniska universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Chemistry of Interfaces; Gränsytors kemi;

   Sammanfattning : This thesis is a summary of our studies on (i) the proton and copper adsorption at aqueous illite surfaces, (ii) the proton and copper complexation of humic substances (fulvic acid FA and humic acid HA), (iii) the interaction between illite and fulvic acid, and (iv) the copper complexation behaviors in illite-FA bi-complexant systems. These particular studies were designed to help us develop a framework for modelling heavy metal complexation/adsorption mechanisms at natural particle surfaces. LÄS MER

5. 24. Photochemical alterations of dissolved organic matter : Impact on heterotrophic bacteria and carbon cycling in lakes

   Författare :Stefan Bertilsson; Linköpings universitet; []
   Nyckelord :SAMHÄLLSVETENSKAP; SOCIAL SCIENCES; INTERDISCIPLINARY RESEARCH AREAS; TVÄRVETENSKAPLIGA FORSKNINGSOMRÅDEN;

   Sammanfattning : Globally, the amount of carbon in dissolved organic matter (DOM) is similar to the total amount in the atmosphere. DOM also plays a key role in structuring natural surface waters and affects the physical, chemical, and biological character of these systems. LÄS MER

7. 25. A Passive Sampling System for Monitoring Metals in the Aquatic Environment

   Författare :Lena B Blom; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; metal diffusion; metal monitoring; metal speciation; aquatic systems; passive sampling system;

   Sammanfattning : Water monitoring is undertaken routinely as a requirement of water quality legislation. It is usual that water monitoring is undertaken through spot sampling. A passive sampling system has been developed for the aquatic environment that provides time-averaged (integrated) concentrations for metals. LÄS MER