Sökning: "supercritical"

Visar resultat 1 - 5 av 91 avhandlingar innehållade ordet supercritical.

  1. 1. Supercritical Hydrogenation of Vegetable Oils

    Författare :Maj-Britt Macher; Chalmers University of Technology; []
    Nyckelord :palladium catalyst; supercritical; hydrogenation; silver ion HPLC; rapeseed oil; fatty acid methyl ester; trans fatty acid; palm oil; deactivation; propane;

    Sammanfattning : Vegetable oils were hydrogenated in a supercritical single-phase mixture with propane and hydrogen. The reaction was carried out in a small (0.5 ml) fixed-bed reactor and the influence of different process parameters was investigated. LÄS MER

  2. 2. Packed Column Supercritical Fluid Chromatography : Applications in Environmental Chemistry

    Författare :Nicole Riddell; Bert van Bavel; Robert McCrindle; Ingrid Ericson Jogsten; Jake Ryan; Örebro universitet; []
    Nyckelord :NATURAL SCIENCES; NATURVETENSKAP; NATURVETENSKAP; NATURAL SCIENCES; Supercritical Fluid Chromatography; Mass Spectrometry; Ionization; POPs; APPI; APCI; chiral; achiral; packed column;

    Sammanfattning : Although gas and liquid chromatography have emerged as dominant separation techniques in environmental analytical chemistry, these methods do not allow for the concurrent analysis of chemically diverse groups of persistent organic pollutants (POPs). There are also a small number of compounds which are not easily amenable to either of these traditional separation techniques. LÄS MER

  3. 3. Fundamental Investigations of Supercritical Fluid Chromatography

    Författare :Martin Enmark; Torgny Fornstedt; Arvind Rajendran; Karlstads universitet; []
    Nyckelord :NATURAL SCIENCES; NATURVETENSKAP; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; NATURVETENSKAP; NATURAL SCIENCES; Supercritical Fluid Chromatography; SFC; Modeling; Adsorption Isotherms; Scale-up; Peak Distortion; Injection; Design of Experiments; Perturbation Peak Method; Elution by Characteristic Points Method; Method transfer; Kemi; Chemistry;

    Sammanfattning : This thesis aims at a deeper understanding of Supercritical FluidChromatography (SFC). Although preparative SFC has started to replace Liquid Chromatography (LC) in the pharmaceutical industry - because of its advantages in speed and its less environmental impact - fundamental understanding is still lacking. LÄS MER

  4. 4. Preparation of Pharmaceutical Powders using Supercritical Fluid Technology : Pharmaceutical Applications and Physicochemical Characterisation of Powders

    Författare :Sitaram P. Velaga; Johan Carlfors; Kristiina Järvinen; Uppsala universitet; []
    Nyckelord :MEDICAL AND HEALTH SCIENCES; MEDICIN OCH HÄLSOVETENSKAP; MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; Pharmaceutics; Supercritical fluid; Gas Anti-Solvent; SEDS; Crystallisation; Particle design; Polymorphs; Dry powder inhalation; Solid-state behaviour; Therapeutic proteins; Precipitation; Stability; Recombinant human growth hormone hGH ; Galenisk farmaci; Pharmaceutics; Galenisk farmaci;

    Sammanfattning : The main aim of the thesis was to explore the potential of supercritical fluid (SF) techniques in the field of drug delivery. In particular, the relatively recently developed solution-enhanced dispersion by supercritical fluids (SEDS) technology has been employed in the preparation of particles/powders. LÄS MER

  5. 5. Fundamental research on supercritical fluid extraction kinetics : From on-line measurements to inverse modeling

    Författare :Victor Abrahamsson; Centrum för analys och syntes; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; supercritical fluid extraction; supercritical fluid chromatography; linseed; microalgae; extraction kinetics; inverse modeling; curve resolution;

    Sammanfattning : Supercritical fluid extraction is an extraction technique suitable for lipophilic compounds from solid samples. Most commonly supercritical carbon dioxide is the main component in the extraction phase, rendering the technique relatively environmentally benign. LÄS MER