Search for dissertations about: "volume fraction"

Showing result 1 - 5 of 319 swedish dissertations containing the words volume fraction.

  1. 1. Macroscopic Volume and Free Volume of Polymer Blends and Pressure-densified Polymers

    Author : Marcus Schmidt; Chalmers University of Technology; []
    Keywords : free-volume theories; refractive index; Lorentz-Lorenz equation; loss tangent; Avrami equation; freezing fractions; copolymers; polymer blends; pressure dilatometry; Tait equation of state; free-volume distributions; pressure-densified polymers; entropy of melting; dynamic-mechanical analysis; positronium; positron annihilation; free volume; cavity size; polymers; bulk modulus; PVT; phase separation; compressibility; thermal expansivity;

    Abstract : The macroscopic volume V as a function of pressure P and temperature T is obtained from PVT measurements. PVT data is sensitive to the state of polymers and changes therein. Moreover, PVT data gives access to the free-volume fraction. READ MORE

  2. 2. Robust intersection of hexahedral meshes and triangle meshes with applications in finite volume methods

    Author : Frida Svelander; Göteborgs universitet; Göteborgs universitet; Gothenburg University; []
    Keywords : NATURVETENSKAP; NATURVETENSKAP; NATURAL SCIENCES; NATURAL SCIENCES; triangle-hex intersection; overlapping triangles; degenerate mesh; volume fraction; area fraction; cut cell; conjugated heat transfer.; triangle-hex intersection;

    Abstract : The topic of this thesis is the intersection of a structured hexahedral grid and one or more triangle meshes. The interest in the problem has arisen in connection with a finite volume method for simulation of conjugated heat transfer. READ MORE

  3. 3. Free Volume Determination in Polymers and Polymer Blends

    Author : Camilla Wästlund; Chalmers University of Technology; []
    Keywords : positronium formation; crystallinity; polymer blends; inhibition; polymers; free volume; positron annihilation; phase separation; distribution;

    Abstract : The free volume of a polymer, which corresponds to the unoccupied regions accessible to segmental motions, is an important parameter for understanding and predicting many of its characteristic properties. The concept of free volume is the basis for understanding the molecular mobility in polymers. READ MORE

  4. 4. Water diffusion and free volume in hydrophilic polymers

    Author : Charlotte Trotzig; Centrum för analys och syntes; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Physical chemistry; free volume; self-diffusion; degree of crystallinity; glass transition temperature; tensile storage modulus; surface tension; isotherm; HPMC; PEO; water; triacetin; clay; Macromolecular chemistry; dynamic mechanical analysis; Fysikalisk kemi; differential scanning calorimetry; nuclear magnetic resonance; positron annihilation; Makromolekylär kemi;

    Abstract : During moisture uptake in polymers, the diffusion of the water molecules is believed to occur via unoccupied voids. These voids are called free volume cavities and their sizes are continuously altered when the moisture content in the polymer is enhanced. READ MORE

  5. 5. On the assessment of right ventricular function using cardiac magnetic resonance imaging and echocardiography

    Author : Stina Jorstig; Per Thunberg; Kent Emilsson; Mats Lidén; Micael Waldenborg; Einar Heiberg; Örebro universitet; []
    Keywords : MEDICAL AND HEALTH SCIENCES; MEDICIN OCH HÄLSOVETENSKAP; MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; right ventricle; stroke volume; ejection fraction; cardiac magnetic resonance; ehocardiography; Kirurgi; Surgery;

    Abstract : Transthoracic echocardiography (TTE) and cardiac magnetic resonance (CMR) imaging are two commonly used imaging modalities for evaluating the size and function of the heart. There are advantages and disadvantages associated with both modalities when examining the right ventricle (RV). READ MORE