Sökning: "particulate nitrogen"

Visar resultat 1 - 5 av 60 avhandlingar innehållade orden particulate nitrogen.

  1. 1. Cyanobacterial Nitrogen Fixation in the Baltic Sea : With focus on Aphanizomenon sp

    Författare :Jennie B. Svedén; Jakob Walve; Helle Ploug; Angela Wulff; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; cyanobacteria; Baltic Sea; nitrogen fixation; Aphanizomenon sp.; dissolved nitrogen; particulate nitrogen; sedimentation; Marine Ecology; marin ekologi;

    Sammanfattning : Cyanobacteria are widely distributed in marine, freshwater and terrestrial habitats. Some cyanobacterial genera can convert di-nitrogen gas (N2) to bioavailable ammonium, i.e. perform nitrogen (N) fixation, and are therefore of profound significance for N cycling. LÄS MER

  3. 2. Nitrogen Cycling at Cold Climate Mine Sites in Northen Sweden

    Författare :Lino Nilsson; Anders Widerlund; Anders Lundqvist; Luleå tekniska universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Nitrogen; Mining; Cycling; nutrients; Isotopes; Nitrogen-model; modelling; numerical-modelling; Isotope-tracing; Tracing; Isotope; geochemistry; Applied Geology; Tillämpad geologi;

    Sammanfattning : High nitrogen discharge from mining sites has been an environmental issue that has been closely studied in the recent years. The environmental effects of high nitrogen discharge are mainly eutrophication, but can also lead to changed species composition and algae blooms. LÄS MER

  4. 3. Particulate Flows in Aftertreatment Systems

    Författare :Henrik Ström; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Modeling; Computational fluid dynamics; Exhaust gas aftertreatment; Particulate matter; Multiphase flow; Particulate flow;

    Sammanfattning : Emissions from internal combustion engines contain many components that have a detrimental effect on the environment and on human health, such as nitrogen oxides (NOx) and particulate matter (PM). In addition, the final product of any combustion of fossil fuel - carbon dioxide (CO2) - contributes to global warming. LÄS MER

  5. 4. Predictive Modelling of Aquatic Ecosystems at Different Scales using Mass Balances and GIS

    Författare :Andreas Gyllenhammar; Lars Håkanson; Lars Brydsten; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Earth sciences; mass balance model; dynamic model; scales; marine fish farms; rainbow trout; nutrients; suspended particulate matter; phosphorus; nitrogen; GIS; basin delineation; regionalisation; coastal areas; aquatic foodweb; fishing quotas; Baltic Sea; Archipelago Sea; Okavango Delta; Geovetenskap; Earth sciences; Geovetenskap;

    Sammanfattning : This thesis presents models applicable for aquatic ecosystems. Geographical Information Systems (GIS) form an important part of the thesis. The dynamic mass balance models focus on nutrient fluxes, biotic/abiotic interactions and operate on different temporal and spatial scales (site, local, regional and international). LÄS MER

  7. 5. Tailored process gases for laser powder bed fusion

    Författare :Camille Nicole Géraldine Pauzon; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Helium; Laser powder bed fusion; AM process productivity; Spatter particles; Residual oxygen; 316L stainless steel; Argon; Nitrogen; Additive manufacturing; Process atmosphere; Process stability; Residual stresses.; Ti-6Al-4V; Alloy 718;

    Sammanfattning : Metal laser powder bed fusion (L-PBF) allows for production of complex components using the energy from a laser to locally melt micron-sized powder following a layer-wise approach. Considerable scientific efforts are focused on addressing the influence of the process parameters on the melting stability and the control of material properties, while developing necessary monitoring and characterization tools. LÄS MER