Sökning: "Constant capacitance model"

Visar resultat 1 - 5 av 15 avhandlingar innehållade orden Constant capacitance model.

  1. 1. Acid-base properties of and metal ion affinity for oxygen-delignified kraft pulps

    Författare :Karin Athley; KTH; []
    Nyckelord :Oxygen-delignified kraft pulps; Carboxylate groups; Potentiometric titration; Acid base properties; Constant capacitance model; Metal ion dsitribution; Surface complexes; Complex formation; Donnan theory;

    Sammanfattning : .... LÄS MER

  3. 2. Modeling of glyphosate and metal-glyphosate speciation in solution and at solution-mineral interfaces

    Författare :Caroline Jonsson; Staffan Sjöberg; Per Persson; Bernd Nowack; Umeå universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; herbicide; glyphosate; surface complexation model; speciation; goethite; aged gamma-alumina; bayerite; manganite; cadmium II ; aluminium III ; potentiometric titration; adsorption; Chemistry; Kemi;

    Sammanfattning : Glyphosate (N-(phosphonomethyl)glycine, PMG, H3L) is a widely used organophosphorous herbicide. It interacts with metal ions and mineral surfaces, which may affect its mobility, degradation and bioavailability in the environment. However, these interactions are far from fully understood. LÄS MER

  4. 3. Cation adsorption properties of substituted kraft fibres : an experimental and thermodynamic modelling study

    Författare :Ola Sundman; Lars-Olof Öhman; Per Persson; Janne Laine; Umeå universitet; []
    Nyckelord :MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; Kraft fibres; Donnan equilibria; ion exchange; acid base properties; potentiometric titrations; thermodynamic modelling; NPEs; GaAl12 7 ; EXAFS; Chemistry; Kemi;

    Sammanfattning : Acid/base and metal ion adsorption properties have been investigated for a range of chemically modified bleached Kraft fibre materials (pulps). The studies were performed via potentiometric titrations, Flame Atomic Absorbtion (and Emission) Spectroscopy, Inductively Coupled Plasma Optical Emission Spectroscopy and Extended X-ray Absorbtion Fine Structure measurements. LÄS MER

  5. 4. Modelling of Terahertz Planar Schottky Diodes

    Författare :Aik-Yean Tang; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; S-parameter extraction; Electro-thermal; Schottky diodes; Skin effect; Electromagnetic; Frequency multipliers; High-power frequency multiplier; Current crowding; Proximity effect; Submillimetre wave generation and detection; Geometric modelling; Gallium Arsenide;

    Sammanfattning : This thesis deals with the modelling of THz planar Schottky diodes, focusing on analyses of the geometry- dependent parasitics and the diode chip thermal management. Moving towards higher operating frequencies, the electromagnetic couplings pose significant limitations on the diode performance. LÄS MER

  7. 5. Surface reactions in aqueous suspensions of fluorapatite and iron oxides

    Författare :Mathias Jarlbring; Luleå tekniska universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Chemistry of Interfaces; Gränsytors kemi;

    Sammanfattning : The main objectives have been to study and model surface reactions of aqueous suspen-sions of minerals with relevance to the dephosphorization of iron oxides by reverse froth flotation. Synthetic hematite, maghemite and fluorapatite in colloidal forms were prepared and thoroughly characterized using XRD, SEM, BET, FT-IR and FT-Raman. LÄS MER