Sökning: "Gas adsorption"

Visar resultat 1 - 5 av 160 avhandlingar innehållade orden Gas adsorption.

  1. 1. Gas Adsorption and Permeation in MFI Zeolites and Membranes

    Författare :Sang Wirawan; [2009]
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; composite membranes; TPD; MFI zeolites; WGS membrane reactor; adsorption; FTIR spectra;

    Sammanfattning : The single and multi component gas adsorption behavior on silicalite-1 and cation exchanged MZSM-5 zeolites (M = H, Na, and Ba) were investigated by a step change response method. Temperature programmed desorption (TPD) and in-situ fourier transform infrared (FTIR) spectroscopy were also performed to study the type of adsorbed species and their thermal stabilities. LÄS MER

  2. 2. Molecular overlayers on homogeneous and heterogeneous metal surfaces studied by core-level photoemission

    Detta är en avhandling från Department of Synchrotron Radiation Research, Lund University

    Författare :Maria Smedh; Lunds universitet.; Lund University.; [2001]
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; photoelectron spectroscopy; core-level photoemission; electron energy loss spectroscopy; single crystal surfaces; metal surfaces; heterogeneous surfaces; adsorption; adsorbed molecules; hydrocarbons; molecular vibrations; carbon monoxide; adsorption sites; adsorption energy; diffusion; dissociation; Physics; Fysik; Fysicumarkivet A:2001:Smedh;

    Sammanfattning : The main topic of this thesis is the investigation of small molecules adsorbed on metal surfaces by means of core-level photoemission spectroscopy. The thesis consists of three parts; The first group of papers concerns the effects of internal molecular vibrations on the core-level photoemission spectra. LÄS MER

  3. 3. Studies of inorganic crystal structures and gas adsorption process in mesoporous crystals : New approach through analysis of electron charge distribution by synchrotron powder X-ray diffraction

    Detta är en avhandling från Stockholm : Institutionen för fysikalisk kemi, oorganisk kemi och strukturkemi

    Författare :Norihiro Muroyama; Stockholms universitet.; [2008]
    Nyckelord :XRD; Mesoporous; Gas adsorption; Laves Phase; MEM; strukturkemi; Structural Chemistry;

    Sammanfattning : Using synchrotron powder XRD experiments, I studied (i) structures of silica mesoporous MCM-41 and MCM-48 crystals, (ii) gas adsorption processes of Ar and N2 in the mesopores of the mesoporous crystals, and (iii) bonding features of CaAl2-xZnx crystals through the analysis of electron charge density distributions. In the case of mesoporous crystals, the following two different approaches were taken depending on the number of observed X-ray reflections1. LÄS MER

  4. 4. Adsorption of surface active elements on the iron (100) surface A study based on ab initio calculations

    Detta är en avhandling från Stockholm : KTH

    Författare :Weimin Cao; KTH.; [2009]
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; sulfur; oxygen; surface adsorption; iron surface; ab initio calculations; adsorption energy; work function; difference charge density; thermodynamic stability; average velocity; TECHNOLOGY Materials science; TEKNIKVETENSKAP Teknisk materialvetenskap;

    Sammanfattning : In the present work, the structural, electronic properties, thermodynamic stability and adatom surface movements of oxygen and sulfur adsorption on the Fe surface were studied based on the ab initio method.Firstly, the oxygen adsorbed on the iron (100) surface is investigated at the three adsorption sites top, bridge and hollow sites, respectively. LÄS MER

  5. 5. Design of Cellulose-based Materials by Supramolecular Assemblies

    Detta är en avhandling från KTH Royal Institute of Technology

    Författare :Tobias Benselfelt; KTH.; KTH.; [2019]
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Adhesion; adsorption; alginate; assemblies; biodegradable; biomaterials; biopolymers; cellulose; cellulose nanofibrils; CNFs; gas barrier; hemicellulose; interfaces; ion-ion correlation; latex; layer-by-layer; metal-ligand complexes; montmorillonite; multivalent ions; packaging; PISA; polyelectrolyte multilayers; polyelectrolytes; polysaccharides; RAFT; renewable; specific ion effects; supramolecular; surfaces; sustainable; thin films; water-resilient; xyloglucan; Fiber- och polymervetenskap; Fibre and Polymer Science;

    Sammanfattning : Due to climate change and plastic pollution, there is an increasing demand for bio-based materials with similar properties to those of common plastics yet biodegradable. In this respect, cellulose is a strong candidate that is already being refined on a large industrial scale, but the properties differ significantly from those of common plastics in terms of shapeability and water-resilience. LÄS MER