Sökning: "aromatic substances"

Visar resultat 1 - 5 av 29 avhandlingar innehållade orden aromatic substances.

  1. 1. Bush Encroachment and the Role of Browse in Cattle Production : An ecological perspective from a bush encroached grazing system, Olifants Drift, Kgatleng District, Southeast Botswana

    Författare :Nkobi Moleele; Norman Owen-Smith; Stockholms universitet; []
    Nyckelord :savannas; bush encroachment; carrying capacity; browse; biomass; range degradation; colour infrared photographs; Landsat Thematic Mapper; mid infrared bands; tannins; toxins; aromatic substances; Dicrostachys cinerea; Grewia flava; NDVI; Olifants Drift; Botswana; naturgeografi; Physical Geography;

    Sammanfattning : The increase in density and cover of woody plant species is coincident with the introduction of cattle in southern Africa, and it is a wide spread phenomenon in the savannas of the world. The causes are little understood, but can only be speculated to be either anthropogenic or natural or a combination of both. LÄS MER

  3. 2. Applications of Solid-Phase Microextraction to Chemical Characterization of Materials Used in Road Construction

    Författare :Bing Tang; Ulf Isacsson; Xiaohu Lu; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Asphalt release agents; Petroleum oils; Vegetable oils; Bituminous sealants; Bitumen; Emissions; Monocyclic aromatic hydrocarbons; Polycyclic aromatic hydrocarbons; Fourier Transform Infrared Spectroscopy - Attenuated Total Reflectance; Gel Permeation Chromatography; Mass Spectrometry; Gas Chromatography - Mass Spectrometry; Thermogravimetric Analysis; Headspace; Solid-phase microextraction; Calibration.; Building engineering; Byggnadsteknik;

    Sammanfattning : Environmental and health aspects of road materials have been discussed for a long time, mostly regarding bitumen and bitumen fumes. However, just a few studies on other types of road materials have been reported. LÄS MER

  4. 3. Fluorimetric Bioprobe Based on DNA-dye Intercalation - Application in Enviromental and Clinical Monitoring

    Författare :Yang Liu; Tillämpad biokemi; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Bioteknik; Biotechnology; Biokemisk teknik; Biochemical technology; Antibiotics; Toxic aromatic compounds; Doxorubicin; High throughput screening; Fluorimetric assay; DNA;

    Sammanfattning : Nucleic acids have many unique structural features that offer reliable means of recognizing and monitoring many compounds of medical or environmental importance. In recent years, there has been an enormous increase in the use of nucleic acids as a tool to determine the chemical compounds of environmental and clinical interest and the major research activities in these areas have been directed towards the design of sequence-selective biosensors based on hybridization. LÄS MER

  5. 4. Chemical and bioanalytical characterisation of PAH-contaminated soils : identification, availability and mixture toxicity of AhR agonists

    Författare :Maria Larsson; Magnus Engwall; Jessika Hagberg; Peter Haglund; Örebro universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Polycyclic aromatic compounds; Soil; Risk assessment; Mixture studies; AhR-mediated activity; REPs; GC MS; H4IIE-luc bioassay; Chemistry; Kemi;

    Sammanfattning : Contaminated soils are a worldwide problem. Polycyclic aromatic hydrocarbons (PAHs) are common contaminants in soil at former industrial areas, especially at old gasworks sites, gas stations and former wood impregnation facilities. LÄS MER

  7. 5. Laser Diagnostics in Combustion - Elastic Scattering and Picosecond Laser-Induced Fluorescence

    Författare :Frederik Ossler; Förbränningsfysik; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Spray; Picosecond laser; Streak camera; Time resolved; Fluorescence lifetimes; 3 – D flow imaging; 2 - D lifetime imaging; Pressure; Temperature; Hydrogen atoms; Oxygen atoms; 3-pentanone; Acetone; Lorenz-Mie theory; Aerosol; Fysicumarkivet A:1999:Ossler; Scattering; Fysik; Physics; Polycyclic aromatic hydrocarbons.;

    Sammanfattning : Elastic scattering and the Lorenz-Mie (LM) theory in particular is used for the characterization of sub-micron- and micron-sized droplets of organic fuels in sprays and aerosols. Calculations on the Lorenz- Mie theory show that backward-sideward scattered visible radiation can be used for unambiguous detection of ensembles of homogeneous droplets of organic substances with diameters around 1 micrometer (size parameter between 2 and 6). LÄS MER