Sökning: "Monoliths"

Visar resultat 1 - 5 av 39 avhandlingar innehållade ordet Monoliths.

1. 1. New Techniques for Sample Preparation in Analytical Chemistry : Microextraction in Packed Syringe (MEPS) and Methacrylate Based Monolithic Pipette Tips

   Författare :Zeki Altun; Lars G Blomberg; Stig Pedersen-Bjergaard; Karlstads universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Liquid Chromatography Tandem Mass Spectrometry; Local Anaesthetics; Microextraction in Packed Syringe; Monoliths; Pipette Tips; Sample Preparation; Analytical chemistry; Analytisk kemi; Kemi; Chemistry;

   Sammanfattning : Sample preparation is often a bottleneck in systems for chemical analysis. The aim of this work was to investigate and develop new techniques to address some of the shortcomings of current sample preparation methods. LÄS MER

3. 2. True Monoliths as Separation Media : Homogeneous Gels for Electrophoresis and Electrochromatography in the Capillary and Microchip Modes

   Författare :Ákos Végvári; Douglas Westerlund; Uppsala universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Biochemistry; capillary electrophoresis; capillary electrochromatography; gel electrophoresis; agarose; polyacrylamide; b-cyclodextrin; DNA; peptide; glutathione; drug enantiomers; microchip; Biokemi; Biochemistry; Biokemi; biokemi; Biochemistry;

   Sammanfattning : The thesis focuses on the development of new homogeneous gels for the separation of drug enantiomers, peptides, DNA and virus by electrophoresis and electrochromatography in capillaries and microchips. This type of separation media offers high resolution and small zone broadening. LÄS MER

4. 3. Porous Polymeric Monoliths by Less Common Pathways : Preparation and Characterization

   Författare :Ahmed Elhaj; Knut Irgum; Sebastiaan Eeltink; Umeå universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Monolith; commodity polymer; thermally induced phase separation; dissolution-precipitation; polymer solvents; porogenic polymer; step-growth polymerization; separation science; melamine-formaldehyde;

   Sammanfattning : This thesis focuses on my endeavors to prepare new porous polymeric monoliths that are viable to use as supports in flow-through processes. Polymer monoliths of various porous properties and different chemical properties have been prepared utilizing the thermally induced phase separation (TIPS) phenomenon and step-growth polymerization reactions. LÄS MER

5. 4. Functionalization and processing of porous powders into hierarchically porous monoliths

   Författare :Petr Vasiliev; Lennart Bergström; Yoshio Sakka; Stockholms universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Porous; zeolite; hierarchical; monolith; nanoparticle; functionalization; amorphization; PCP; SPS; pulsed current processing; spark plasma sintering.; Chemistry; Kemi; Inorganic Chemistry; oorganisk kemi;

   Sammanfattning : Inorganic porous materials are widely used in a number of applications, where is a need to functionalize and produce materials with a multiscale porosity. The first part of the thesis describes how a novel and facile powder processing approach, using pulsed current processing (PCP) or, as it is commonly called, spark plasma sintering (SPS), has been employed to produce mechanically stable, hierarchically porous bodies from different porous powders. LÄS MER

7. 5. New approaches to preparation of macroporous monoliths for use in liquid chromatography

   Författare :Anh Mai Nguyen; Knut Irgum; Tatiana B. Tennikova; Umeå universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; monolith; polycondensation; dissolution-precipitation; epoxy-amine; poly-amide; nylon; emulsion polymerization; characterization; protein separation; liquid chromatography; Analytical chemistry; Analytisk kemi; analytisk kemi; Analytical Chemistry;

   Sammanfattning : High performance liquid chromatography (HPLC) is one of the major techniques in separat-ion sciences. Faster separation and higher efficiency are required to meet ever-growing demands. Despite numerous studies and achievements on improving mass transfer in particulate packings discontinuity seems to be the cornerstone drawback in their development. LÄS MER