Sökning: "nitrification"

Visar resultat 11 - 15 av 62 avhandlingar innehållade ordet nitrification.

1. 11. Nitrogen transformations in wetlands: Effects of water flow patterns

   Författare :Torbjörn Davidsson; Biologiska institutionen; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Hydrobiology; hydrology; infiltration; subsurface flow; surface flow; wetland; nitrogen; Denitrification; mineralization; nitrification; marine biology; aquatic ecology; limnology; Marinbiologi; limnologi; akvatisk ekologi;

   Sammanfattning : In this thesis, I have studied nitrogen turnover processes in watermeadows. A watermeadow is a wetland where water infiltrates through the soil of a grassland field. LÄS MER

3. 12. Reactors and biosensors for improved microbial degradation of acetonitrile

   Författare :Kristina Håkansson; Bioteknik; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Biotechnology; Bioteknik; denitrification; nitrification; on-line analysis and control; Clark electrode; biosensor; biofilm process; acetonitrile; microbial degradation;

   Sammanfattning : Biodegradation is becoming an attractive mode of operation for eliminating toxic chemicals released from industrial processes or already present in the environment. One needs, however, not only to identify organisms capable of degrading such chemicals, but also to address the issue of whether these chemicals, after being degraded, will be toxic to the degrading organisms if present in high concentrations. LÄS MER

4. 13. New Dimensions of Moving Bed Biofilm Carriers : Influence of biofilm thickness and control possibilities

   Författare :MARIA PICULELL; Avdelningen för kemiteknik; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; biofilm control; biofilm thickness; biological wastewater treatment; carrier; moving bed biofilm reactor; nitrification; nitritation; organic removal; process optimization; scaling; suspended growth;

   Sammanfattning : The moving bed biofilm reactor (MBBR) is a biological wastewater treatment process in which microorganisms grow as biofilms on suspended carriers. Conventionally, MBBRs are mainly designed and optimized based on the carrier surface area, neglecting the dynamic relationship between carrier design, reactor operation and biofilm characteristics, such as biofilm thickness and the composition of the microbial community. LÄS MER

5. 14. Effects of heavy metal contamination on carbon and nitrogen cycling : An ecological approach to assess risks to soil functions

   Författare :Ingrid Rijk; Alf Ekblad; Dan Berggren Kleja; Erik Karltun; Örebro universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; heavy metals; soil contamination; stable isotopes; N cycling microbial guilds; 13C; 15N; nitrification; denitrification; biochar; soil respiration; microbial activity; bioavailability;

   Sammanfattning : Soil contamination with heavy metals may disrupt soil microorganisms with important roles in carbon (C) and nitrogen (N) cycling. However, there is a lack of understanding on how microorganisms are affected in soil, which may lead to a mismatch when assessing risks of contaminants to field soils. LÄS MER

7. 15. On Modeling the Dynamics of Fixed Biofilm Reactors. With focus on nitrifying trickling filters

   Författare :Torsten Wik; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; operation; transfer functions; biofilm reactors; adsorption; dormancy; modeling; dynamics; nitrification;

   Sammanfattning : Fixed biofilms, which are matrix-enclosed populations of organisms attached to solid surfaces, are increasingly used in environmental biotechnology processes, such as the treatment of potable water and wastewater. This thesis aims to give some insight into the dynamic modeling of biofilms and fixed biofilm reactors, with a focus on nitrifying trickling filters (NTFs) for the treatment of wastewater. LÄS MER