Sökning: "Carbon C"

Visar resultat 21 - 25 av 781 avhandlingar innehållade orden Carbon C.

  1. 21. Fast Chemistry by Microwave Heating : First Descriptions of Highly Enantioselective Microwave Protocols for Metal Catalysis; First Descriptions of in-situ Gas Generation for Fast Combinatorial Microwave Chemistry

    Författare :Nils-Fredrik K. Kaiser; C. O.; Uppsala universitet; []
    Nyckelord :MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; Pharmaceutical chemistry; Farmaceutisk kemi; Pharmaceutical chemistry; Farmaceutisk kemi; Organic Pharmaceutical Chemistry; organisk farmaceutisk kemi;

    Sammanfattning : Microwave heating was applied to different palladium-catalyzed allylic substitution reactions. The use of various nucleophiles demonstrated C-, N-, O- and S- nucleophilicity. High yields and stereopurities of the corresponding alkyls, amides, ethers and sulfones were afforded after only 30 – 120 s of heating. LÄS MER

  3. 22. Development of electron microscopy towards nano-structured porous materials : Focus on novel zeolites from layered silicates and chiral mesoporous nanotubes

    Författare :Juanfang Ruan; Osamu Terasaki; James C. Vartuli; Stockholms universitet; []
    Nyckelord :Transmission electron microscopy; Layered silicates; Chiral mesoporous nanotubes; strukturkemi; Structural Chemistry;

    Sammanfattning : Three novel zeolites (M-IEZ-MWW, IEZ-FER and IEZ-CDO) have been successfully synthesised from the corresponding precursors. Structure characterisation of those materials was conducted by TEM. LÄS MER

  4. 23. Event stratigraphy for the Last Glacial-Holocene transition in eastern middle Sweden

    Författare :Jonas Björck; Michael J.C Walker; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Last Glacial-Holocene transition; event stratigraphy; eastern middle Sweden; pollen; plant macrofossils; marine calcareous fossils; microtephra; radiocarbon dating; clay varve chronology; GRIP; ice-core chronology; calendar year chronology; Preboreal oscillation; Yoldia Sea; Baltic Ice Lake; Quaternary Geology; kvartärgeologi;

    Sammanfattning : This thesis outlines an event stratigraphy for the Last Glacial-Holocene transition in eastern middle Sweden. Events are short-lived occurrences that have left traces in the geological record and which, therefore, may be used for correlation and inter-regional comparisons. LÄS MER

  5. 24. Nanocomposite films for corrosion protection

    Författare :Majid Sababi; Jinshan Pan; J.M.C. (Arjan) Mol; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; corrosion protection; nanocomposite; coating; tool alloy; layer‐by‐layer; polarization; passivity; nanomechanical; topography; Mefp‐ 1; ceria nanoparticle; PAni; UV‐cure; AFM; Peak Force QNM; EIS; SEM; CRM; QCM‐D; ATR‐FTIR;

    Sammanfattning : This thesis describes technical and scientific aspects of new types of composite films/coatings for corrosion protection of carbon steel, composite films with nanometer thickness consisting of mussel adhesive protein (Mefp‐1) and ceria nanoparticles, and polymeric composite coatings with micrometre thickness consisting of conducting polymer and ceria nanoparticles in a UV‐curing polyester acrylate (PEA) resin.The influence of microstructure on corrosion behaviour was studied for a Fe‐Cr‐V‐N alloy containing micro‐sized nitrides with different chemical composition spread in martensitic alloy matrix. LÄS MER

  7. 25. Melt flow and surface stability effects on polymer flammability : A study on polystyrene, flexible polyurethane foam and polyolefin composites

    Författare :Roland H. Krämer; Ulf W. Gedde; Norman C. Billingham; KTH; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Melt; flow; dripping; collapse; combustion; pool fire; feed‐back; gasification; heat release; flammability; nanocomposites; molar mass; intumescence; polyurethane; Polymer chemistry; Polymerkemi;

    Sammanfattning : Our ability to accurately determine the flammability properties of polymers is hampered bythe erratic effects of deformation and liquid flow that occur during polymer combustion.This study aims to improve the understanding of such effects at several levels: The often obvious impact of melt flow on standardized flammability test methods forelectrical appliances is described to identify the need and to motivate others to worktowards an improved material characterization. LÄS MER