Sökning: "critical layer thickness"

Visar resultat 1 - 5 av 64 avhandlingar innehållade orden critical layer thickness.

1. 1. The band offset and the critical layer thickness in III-V compound semiconductor heterostructures

   Författare :Shu Min Wang; Chalmers tekniska högskola; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; interface morphology; molecular beam epitaxy; band offset; transmission electron microscopy; InGaAs; strain; photoluminescence; critical layer thickness; quantum wells; heterostructures; III-V compounds;

   Sammanfattning : .... LÄS MER

3. 2. Tailored layer-by-layer films of nanofibrillated cellulose

   Författare :Erdem Karabulut; Lars Wågberg; Lennart Piculell; Eva Blomberg; KTH; []
   Nyckelord :layer-by-layer assembly; nanofibrillated cellulose; thin film; surface adsorption; polyelectrolytes;

   Sammanfattning : The preparation of multifunctional films, coatings and membranes from natural, sustainable and low-cost raw materials has attracted considerable interest during the last decade. In this respect, cellulose-based products possess a great promise for research and industry due both to the availability of large amounts of material in nature and to the preparation of new classes of nano-sized and well-characterized building-blocks of cellulose from trees or annual plants. LÄS MER

4. 3. An Experimental Study on Micro-Hydrodynamics of Evaporating/Boiling Liquid Film

   Författare :Shengjie Gong; Ma Weimin; Horst-Michael Prasser; KTH; []
   Nyckelord :liquid film; critical thickness; boiling; critical heat flux; rupture; dry spot; confocal optical sensor; SRA - Energy; SRA - Energi;

   Sammanfattning : Study of liquid film dynamics is of significant importance to the understanding and control of various industrial processes that involve spray cooling (condensation), heating (boiling), coating, cleaning and lubrication. For instance, the critical heat flux (CHF) of boiling heat transfer is one of the key parameters ensuring the efficiency and safety of nuclear power plants under both operational and accident conditions, which occurs as the liquid layers (microlayer and macrolayer) near the heater wall lose their integrity. LÄS MER

5. 4. On stability and receptivity of boundary-layer flows

   Författare :Nima Shahriari; Ardeshir Hanifi; Dan S. Henningson; Peter J. Schmid; KTH; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; boundary layer receptivity; acoustic receptivity; swept-wing flow; crossflow vortices; roughness element; global stability analysis; direct numerical simulation; plasma actuator; Engineering Mechanics; Teknisk mekanik;

   Sammanfattning : This work is concerned with stability and receptivity analysis as well as studies on control of the laminar-turbulent transition in boundary-layer flows through direct numerical simulations. Various flow configurations are considered to address flow around straight and swept wings. LÄS MER

7. 5. Modeling the effects of knots in Structural Timber

   Författare :Christina Foley; Avdelningen för Konstruktionsteknik; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Material technology; Byggnadsteknik; Building construction; three-dimensional fiber paradigm; fiber deviation; knots; annual growth layer; material matrix; knot bump; structural timber; load carrying capacity; Materiallära; critical knot; knot distance ratio; local principal material directions; stiffness; materialteknik;

   Sammanfattning : The main purpose of the pursued research is to increase knowledge of the effects of knots in structural timber so that characteristics of weaker timber may be determined and applied to improve current grading techniques. In the process, a three-dimensional fiber paradigm was established, which describes variations of local principle material axes in timber containing knots. LÄS MER