Sökning: "phase behavior"

Visar resultat 16 - 20 av 615 avhandlingar innehållade orden phase behavior.

1. 16. Complex Phase Behavior in Thermoelectric Mg2Si1-xSnx Alloys and Development of Transient Plane Source Method for Structural Characterization

   Författare :Andrey Sizov; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; multiphase structure; quality control; inhomogeneity tests; Rietveld refinement; Transient Plane Source method; isotropic and anisotropic materials; defects detection; advance measurements of thermal properties; X-ray diffraction; structural characterization; spark plasma sintering; magnesium silicide-stannide alloys; complex behavior; thermoelectric properties; thermal conductivity vs. probing depth;

   Sammanfattning : The thermoelectric effect was discovered nearly 200 years ago, but it started to be utilized for waste heat recovery only fairly recently. From an economical point of view, such applications requires a cheap and efficient material, which is able to convert heat energy into electricity. LÄS MER

3. 17. Mathematical Modeling of Transport Phenomena in Polymer Electrolyte and Direct Methanol Fuel Cells

   Författare :Erik Birgersson; KTH; []
   Nyckelord :Fuel Cell; DMFC; PEFC; model; visual cell; scale analysis; one-phase; two-phase;

   Sammanfattning : This thesis deals with modeling of two types of fuel cells:the polymer electrolyte fuel cell (PEFC) and the directmethanol fuel cell (DMFC), for which we address four majorissues: a) mass transport limitations; b) water management(PEFC); c) gas management (DMFC); d) thermal management. Four models have been derived and studied for the PEFC,focusing on the cathode. LÄS MER

4. 18. Phase transitions in magnetic metamaterials

   Författare :Björn Erik Skovdal; Björgvin Hjörvarsson; Vassilios Kapaklis; Gunnar K. Pálsson; Peter Schiffer; Uppsala universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Magnetic metamaterials; artificial spin ice; mesospins; magnetic nanostructures; mesoscopic spin systems; multiscale materials; tri-criticality; emergence; edge modes;

   Sammanfattning : Magnetic metamaterials consisting of arrays of densely packed, two-dimensional nanoscale magnetic islands have degrees of freedom on two separate length scales: inside the islands, and among them. These degrees of freedom can be tuned by e.g. size, shape, island separation and lattice geometry. LÄS MER

5. 19. Modeling of phase transformations and cyclic plasticity in pearlitic steels

   Författare :Björn Andersson; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Phase transformations; TRIP; Pearlitic steel; FEM; Cyclic plasticity; Homogenization;

   Sammanfattning : The low rolling resistance in railway transportation is a key factor for its high efficiency, but it comes at the price of very high contact pressure between the rail and wheel. Due to the high stresses and the large number of load cycles during railway operation, both the rail and the wheel can be susceptible to fatigue crack initiation and propagation. LÄS MER

7. 20. NMR Self-Diffusion Studies and Stability Studies of Emulsions

   Författare :Ingrid Lönnqvist; LTH Ingenjörshögskolan vid Campus Helsingborg; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; coalescence; emulsion stability; size distribution; restricted diffusion; self-diffusion coefficient; self-diffusion PGSE NMR; surfactant; emulsifier; continuous phase; microemulsion; phase diagram; emulsion; multiple emulsion; cream; conductivity; Physics; Fysik; Chemistry; Kemi;

   Sammanfattning : The aim of this study is to characterize emulsion systems by self-diffusion PGSE NMR methods. The specifics of the emulsions studied are all taken from the literature and they are of the W/O or O/W type stabilized with different emulsifiers. LÄS MER