Sökning: "Ca-phosphates"

Visar resultat 1 - 5 av 6 avhandlingar innehållade ordet Ca-phosphates.

  1. 1. The evolution of lunar breccias : U-Pb geochronology of Ca-phosphates and zircon using Secondary Ion Mass Spectrometry

    Författare :Fiona Karen Thiessen; Martin Whitehouse; Alexander Nemchin; Victoria Pease; Barbara Cohen; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Moon; impact breccias; Apollo missions; impact event; Late Heavy Bombardment; zircon; Ca-phosphates; U-Pb; SIMS; geochronology; Geology; geologi;

    Sammanfattning : Planetary bodies in our Solar System, including the Moon, were exposed to an intense asteroid bombardment between ~4.5-3.8 Ga, shaping their surfaces and leaving visible “footprints” in the form of large impact basins. The end of this period (~4. LÄS MER

  3. 2. Soluble and Plant Available Phosphorus in Acid Soils

    Författare :Ann-Mari Fransson; Biologiska institutionen; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; solubilisation mechanisms; Phosphorus extractions; Oxalate extraction; P fertilisation; Plant ecology; Växtekologi;

    Sammanfattning : The P availability and solubility differ between soils and plants seem to have different ways of utilising the P present. The many P fractions present in soil interact and are closely related to another and transformations may easily occur. Due to this more P than the soluble fraction is available to plants. LÄS MER

  4. 3. Ash transformation in single-pellet combustion and gasification of biomass with special focus on phosphorus

    Författare :Ali Hedayati; Marcus Öhman; Rainer Backman; Luleå tekniska universitet; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Energy Engineering; Energiteknik;

    Sammanfattning : The utilization of different biomass feedstocks in thermal conversion systems can contribute towards mitigation of global warming. However, the formation of different ash fractions (i.e. LÄS MER

  5. 4. Ash transformation in thermochemical conversion of different biomass resources with special focus on phosphorus

    Författare :Ali Hedayati; Marcus Öhman; Christoffer Boman; Kentaro Umeki; Anita Pettersson; Luleå tekniska universitet; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; agricultural biomass; forest residues; sewage sludge; ash transformation; release; potassium; phosphorus; combustion; gasification; bio charcoal; phosphorus recovery; Energy Engineering; Energiteknik;

    Sammanfattning : A great potential exists for increasing the use of bioenergy in thermochemical processes by utilizing agricultural biomass, forest residues, and sewage sludge that have high availability. Many of these biomass assortments have high ash contents with relatively high concentrations of ash-forming elements such as potassium (K), calcium (Ca), silicon (Si), and phosphorus (P). LÄS MER

  7. 5. Experimental studies of ash transformation processes in combustion of phosphorus-rich biomass fuels

    Författare :Alejandro Grimm; Britt-Marie Steenari; Luleå tekniska universitet; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Energy Engineering; Energiteknik;

    Sammanfattning : The present thesis is a summary of eight papers dealing with experimental studies on bed agglomeration, slag formation, formation of deposits and fine particulate matter during combustion of phosphorus-rich biomass fuels. The experimental procedures were performed in a bubbling fluidized bed (5 kW), two fixed bed appliances (20 and 15 kW) and in a powder burner (150 kW). LÄS MER