Sökning: "carbon cycle"

Visar resultat 21 - 25 av 404 avhandlingar innehållade orden carbon cycle.

1. 21. Thermodynamic Cycles using Carbon Dioxide as Working Fluid : CO2 transcritical power cycle study

   Författare :Chen Yang; Lundqvist Per; Carlos Infante Ferreria; KTH; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY;

   Sammanfattning : The interest in utilizing the energy in low‐grade heat sources and waste heat is increasing. There is an abundance of such heat sources, but their utilization today is insufficient, mainly due to the limitations of the conventional power cycles in such applications, such as low efficiency, bulky size or moisture at the expansion outlet (e.g. LÄS MER

3. 22. Modelling the terrestrial carbon cycle – drivers, benchmarks, and model-data fusion

   Författare :Zhendong Wu; Institutionen för naturgeografi och ekosystemvetenskap; []
   Nyckelord :Global carbon cycle; Ecosystem modeling; Uncertainty; LPJ-GUESS; Traceability Framework; Model-data fusion; Climate data;

   Sammanfattning : The terrestrial ecosystem sequesters about one-third of anthropogenic emissions each year, thereby providing a critical ecosystem service that slows the rate of increase of atmospheric carbon dioxide and helps mitigate climate change. Observed atmospheric carbon dioxide concentrations exhibit a large inter-annual variability which is considered to be caused primarily by the response of the terrestrial ecosystem to climate change and anthropogenic activity. LÄS MER

4. 23. Oxy-Fuel Combustion Combined Cycles for Carbon Capture

   Författare :Egill Maron Thorbergsson; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; conceptual compressor design; oxy-fuel combustion combined cycles; Graz cycle; Carbon capture and storage; Semi-closed Oxy-fuel Combustion Combined Cycle;

   Sammanfattning : A short and medium term method to decrease carbon dioxide emissions is carbon capture and storage. This method captures carbon dioxide from point sources of emissions and then stores the carbon dioxide in geological formations. LÄS MER

5. 24. Boreal Lake Sediments as Sources and Sinks of Carbon

   Författare :Cristian Gudasz; Tranvik Lars; David Bastviken; Susan Ziegler; Uppsala universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; boreal lakes; allochthonous; lake sediments; sediment mineralization; bacterial production; bacterial biomass; carbon cycle; Freshwater ecology; Limnisk ekologi; Limnologi; Limnology;

   Sammanfattning : Inland waters process large amounts of organic carbon, contributing to CO2 and CH4 emissions, as well as storing organic carbon (OC) over geological timescales. Recently, it has been shown that the magnitude of these processes is of global significance. LÄS MER

7. 25. Advancing prospective life cycle assessment -Experiences from guiding carbon fibre composite development

   Författare :Frida Hermansson; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; climate impact; Life cycle assessment; prospective; carbon fibre composites; energy use;

   Sammanfattning : Life cycle assessment is a powerful tool for quantifying the environmental impacts of goods and services. While most easily done for well-defined and known product systems, there is also a need for a prospective (that is, a future-orientated) approach to assessing developing technologies. LÄS MER