Sökning: "N BOND"

Visar resultat 1 - 5 av 160 avhandlingar innehållade orden N BOND.

  1. 1. Four applications of stochastic processes : Contagious disease, credit risk, gambling and bond portfolios

    Författare :Patrik Andersson; Andreas Nordvall Lagerås; Håkan Andersson; Stewart N. Ethier; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Stochastic processes; Mathematical statistics; Matematisk statistik; Mathematical Statistics; matematisk statistik;

    Sammanfattning : This thesis consists of four papers on applications of stochastic processes. In Paper I we study an open population SIS (Susceptible - Infective - Susceptible) stochastic epidemic model from the time of introduction of the disease, through a possible outbreak and to extinction. The analysis uses coupling arguments and diffusion approximations. LÄS MER

  3. 2. Computational Studies and Design of Biomolecular Diels-Alder Catalysis

    Författare :Mats Linder; Tore Brinck; Kendall N. Houk; KTH; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Computational chemistry; density functional theory; enzyme design; molecular modeling; organocatalysis; stepwise Diels-Alder; oxyanion hole;

    Sammanfattning : The Diels-Alder reaction is one of the most powerful synthetic tools in organic chemistry, and asymmetric Diels-Alder catalysis allows for rapid construction of chiral carbon scaffolds. For this reason, considerable effort has been invested in developing efficient and stereoselective organo- and biocatalysts. LÄS MER

  4. 3. Investigation of [N-X-N]+ and [N-C-N]+ complexes in solution : Exploring Geometry, Stability and Symmetry

    Författare :Alavi Karim; Göteborgs universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; three center four electron; halonium; carbenium; carbonium; pentavalent; symmetry; NMR; variable temperature; counterion; isotopic perturbation of equilibrium;

    Sammanfattning : Halogen bonding is a weak interaction. In this thesis the three center four electron halogen bond, [N−X−N]+, has been studied. The lighter halogens form highly unstable halonium ions that are reactive towards nucleophiles and their complexes were therefore investigated at low temperatures. LÄS MER

  5. 4. Polyhydroxyl and Polyphosphorylcholine functionalized Silica for Hydrophilic interaction liquid Chromatography- Synthesis, characterization and application

    Författare :Nhat Thi Hong Bui; Knut Irgum; Michael Lämmerhofer; Umeå universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Hydrophilic Interaction Chromatography; HILIC; silica; TRIS; acrylamide acrylate; ATRP; iniferter; “controlled living’’ radical polymerization; N; N′-methylenebisacrylamide; MPC; stationary phase; analytisk kemi; Analytical Chemistry;

    Sammanfattning : This thesis focuses on the development of new stationary phases for use in hydrophilic interaction liquid chromatography using TRIS-based and phosphorylcholine typed monomers and porous silica particles as starting substrates. In this thesis, several ways of polymerizing highly hydrophilic mono­mers onto pore surfaces of silica supports are described, based on several “grafting from” schemes. LÄS MER

  7. 5. NHC,P- and N,P-Iridium Catalysts for Hydrogenations and Hydrogen Transfer Reactions

    Författare :Sutthichat Kerdphon; Pher Andersson; Anton Vidal; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Iridium catalyst; carbene; N; P-ligand; asymmetric hydrogenation; alkylation; hydrogen transfer reaction; organisk kemi; Organic Chemistry;

    Sammanfattning : The work described in this thesis is focused on hydrogenation and hydrogen transfer reactions using iridium catalysts. The first part concerns the use of N-heterocyclic carbene-phosphine iridium complexes in alkylation reactions (Chapters 2 and 3) and the hydrogenation of ketones (Chapter 4). LÄS MER