Sökning: "NATURAL SCIENCES Chemistry Physical chemistry Spectroscopy"

Visar resultat 16 - 20 av 376 avhandlingar innehållade orden NATURAL SCIENCES Chemistry Physical chemistry Spectroscopy.

  1. 16. Investigating cellulose structure using solid-state NMR spectroscopy

    Författare :Alexander Idström; Chalmers tekniska högskola; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; CNC; crystallinity index; regenerated cellulose; 2D NMR; native cellulose; pulp; Solid-state NMR; ionic liquids; CP MAS 13C-NMR; hornification;

    Sammanfattning : Cellulose is the most abundant polymer in nature and it is an important constituent in most flowers, trees, and even some animals. Cellulose has an established use in many important products, such as textile fibers, paper and paperboard, and recently new applications have received increased attention. LÄS MER

  2. 17. Imidazole containing polymers complexed with Cu2+ and Zn2+

    Författare :Markus Andersson; Chalmers tekniska högskola; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; vibrational spectroscopy; far-FTIR; EPR; cross-linking; DSC; Coordinating polymer; imidazole; mid-FTIR; metal ion;

    Sammanfattning : An enormous problem for the shipping industry is fouling of marine organisms such as algae andbarnacles on the boat hull. The negative consequences for the society are both economical as well asenvironmental. To prevent fouling in general, biocides are typically incorporated directly into the paint. LÄS MER

  3. 18. Structure and spectroscopy of bio- and nano-materials from first-principles simulations

    Författare :Weijie Hua; Yi LUO; Mauro Stener; KTH; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; soft x-ray spectroscopy; bio- and nano-materials; first-principles simulation; host-guest interaction; generalized energy-based fragmentation; Quantum chemistry; Kvantkemi; Spectroscopy; Spektroskopi; SRA - Molecular Bioscience; SRA - Molekylär biovetenskap;

    Sammanfattning : This thesis is devoted to first-principles simulations of bio- and nano-materials,focusing on various soft x-ray spectra, ground-state energies and structures of isolated largemolecules, bulk materials, and small molecules in ambient solutions. K-edge near-edge x-ray absorption fine structure (NEXAFS) spectra, x-ray emission spectra, andresonant inelastic x-ray scattering spectra of DNA duplexes have been studied by means oftheoretical calculations at the density functional theory level. LÄS MER

  4. 19. The Role of Molecular Heterogeneity in the Structural Dynamics of Aqueous Solutions

    Författare :Sharon Berkowicz; Fivos Perakis; Giulio Monaco; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Water; Aqueous solutions; X-ray scattering; X-ray photon correlation spectroscopy; Dynamic light scattering; kemisk fysik; Chemical Physics;

    Sammanfattning : The liquid-liquid critical point hypothesis suggests that liquid water exists in two liquid states with different local structures, so-called high- and low-density liquid (HDL, LDL). At ambient pressure water locally fluctuates between these two states, with the fluctuations becoming more pronounced as the liquid is supercooled. LÄS MER

  5. 20. Going for gold : A spectroelectrochemical and catalytic study of gold materials

    Författare :Sara Boscolo Bibi; Hansson Tony; Sergey Koroidov; Henrik Öström; Richard Kramer Campen; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Gold oxidation; oxide-derived metals; electrochemistry; X-ray spectroscopy; optical nonlinear spectroscopy; AuNPs supported in metal oxides; mass spectrometry; kemisk fysik; Chemical Physics;

    Sammanfattning : With the increase in demand for renewable energy, understanding chemical processes is essential for improving the design of catalysts in order to achieve better performance. This thesis summarises the experimental investigation of three types of catalytic gold materials: gold oxide formed from gold films, oxide-derived gold (OD-Au) produced from gold films, and gold nanoparticles supported on metal oxides. LÄS MER