Sökning: "Water cycle"

Visar resultat 6 - 10 av 371 avhandlingar innehållade orden Water cycle.

1. 6. Heat and water flows in freezing and thawing soils : numerical modelling, laboratory and field observations

   Författare :Helén Engelmark; Luleå tekniska universitet; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Vattenteknik; Water Resources Engineering;

   Sammanfattning : A laboratory study of infiltration rates into frozen and unfrozen fine sand, including temperature effects of both soil and infiltration water, is reported. The average infiltration rate varied from about 10.6 mm/min for unfrozen conditions, to about 1-2 mm/min for frozen conditions. LÄS MER

3. 7. Advanced power cycles with mixture as the working fluid

   Författare :Maria Jonsson; KTH; []
   Nyckelord :power cycle; mixture working fluid; Kalina cycle; ammonia-water mixture; reciprocating internal combustion engine; bottoming cycle; gas turbine; evaporative gas turbine; air-water mixture; exergy;

   Sammanfattning : The world demand for electrical power increasescontinuously, requiring efficient and low-cost methods forpower generation. This thesis investigates two advanced powercycles with mixtures as the working fluid: the Kalina cycle,alternatively called the ammonia-water cycle, and theevaporative gas turbine cycle. LÄS MER

4. 8. Changes of evapotranspiration and water cycle in China during the past decades

   Författare :Ge Gao; Göteborgs universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Potential evapotranspiration; Actual evapotranspiration; Spatial and temporal characteristic; Trend; Controlling factors; Water cycle; Thornthwaite water balance; China;

   Sammanfattning : Evapotranspiration is the second largest quantity in the water cycle and an important indicator for climate changes. Accurate estimations and better understanding of evapotranspiration are required in hydrologic studies and water resources modelling under stationary and changing climate conditions. LÄS MER

5. 9. Green roof vegetation and storm water runoff quantity - Effects of plant traits, diversity and life strategies

   Författare :Joel Lönnqvist; Godecke-Tobias Blecken; Maria Viklander; Ishi Buffam; Luleå tekniska universitet; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; VA-teknik; Urban Water Engineering; Centrumbildning - Centrum för dagvattenhantering DRIZZLE ; Centre - Centre for Stormwater Management DRIZZLE ;

   Sammanfattning : Green roofs have gained recognition and popularity globally for their potential to help mitigate the negative impacts of urbanization such as habitat loss and disruption of the water cycle caused by increased impervious surfaces. However, there is still a need to enhance our understanding of green roof vegetation dynamics and how they affect plant water use and hydrological function under varying environmental conditions. LÄS MER

7. 10. Fresh Perspectives on the Assessment of Sewage Sludge Management

   Författare :Robin Harder; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; life cycle assessment; biosolids; land application; sewage sludge; pathogen risk; risk assessment; life cycle impact assessment; human toxicity; wastewater; chemical risks;

   Sammanfattning : Sewage sludge management and its role in closing nutrient cycles have received considerable attention in recent years. This thesis quantified phosphorus flows in Gothenburg, Sweden, under current and possible future waste management practices, and aimed to improve the assessment of wastewater and sludge management from an environmental and human health perspective through blending risk assessment (RA) and life cycle assessment (LCA). LÄS MER