Avancerad sökning

Visar resultat 1 - 5 av 2268 avhandlingar som matchar ovanstående sökkriterier.

  1. 1. Finite Element Methods for Interface Problems

    Författare :David Samvin; Peter Hansbo; Kent Salomonsson; Jönköping University; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Finite Element Method; Interface; Embedded; CutFEM; Finita elementmetoden; Sprickor; CutFEM;

    Sammanfattning : This thesis focuses on computationally efficient methods for flow in fractured porous media. Two approaches are presented where the interface is embedded on the underlying finite element mesh. The methods allow for representation of the interface geometry from the underlying discretization and with discontinuities across the interface. LÄS MER

  3. 2. Polyethylene – metal oxide particle nanocomposites for future HVDC cable insulation : From interface tailoring to designed performance

    Författare :Dongming Liu; Ulf Gedde; Mikael Hedenqvist; Richard Olsson; Linda Schadler; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; HVDC; electrical insulation; core-shell nanoparticles; surface modification; silane chemistry; nanocomposites; polyethylene; adsorption; long-term stability; interface; particle dispersion; cavitation; conductivity; HVDC; elektrisk isolation; ytmodifiering; silankemi; nanokompositer; polyeten; adsorption; långtidsstabilitet; ytskikt; partikeldispergering; kavitation; ledningsförmåga; Fiber- och polymervetenskap; Fibre and Polymer Science;

    Sammanfattning : Low-density polyethylene (LDPE) nanocomposites containing metal oxide nanoparticles are considered as promising candidates for insulating materials in future high-voltage direct-current (HVDC) cables. The significant improvement in dielectric properties compared with unfilled polymer is attributed to the large and active interface between the nanoparticles and the polymer. LÄS MER

  4. 3. Development of highly biocompatible neuro-electronic interfaces towards monitoring authentic neuronal signaling in the brain

    Författare :Johan Agorelius; NanoLund: Centre for Nanoscience; []
    Nyckelord :MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; BMI; brain machine interface; Neuro-electronic interface; neurophysiology; brain computer interface; biocompatibility; biocompatible neural interface; neural interface; histology; electrophysiology;

    Sammanfattning : Background: To understand how the neuronal circuits in the brain process information there is a need for novelneuro-electronic interfaces that can interact chronically with brain tissue with minimal disturbance of thephysiological conditions in the tissue, in awake and freely moving animals. For this, there is a need for implantableneuro-electronic interfaces that are mechanically compliant with the tissue and that can remain positionally stablewith respect to the neurons, despite the continuous micromotions in the brain. LÄS MER

  5. 4. Self Assembly at the Liquid Air Interface

    Författare :Niga Petru; Rutland Mark; Ye Shen; KTH; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; VSFS; SFG; interface; crown ethers; ethylene oxides; ionic liquids; fatty acids; domains.; Surface and colloid chemistry; Yt- och kolloidkemi;

    Sammanfattning : The aim of this work is to study the interfacial properties of amphiphilic compounds at the liquid–air interface in an attempt to develop a comprehensive understanding of their orientation as well as the influence of their interaction with the solvent on the interfacial layer properties. Using Vibrational Sum Frequency Spectroscopy (VSFS) as the main tool, the molecular structure of the amphiphilic layer and the amphiphile–solvent relation can be illuminated in great detail – it is arguably the most sensitive surface spectroscopy currently available. LÄS MER

  7. 5. Towards compatibilization of cellulose nanofibrils in polymer matrices : Polymer design for mediating the nanofibril–matrix interface

    Författare :Rosella Telaretti Leggieri; Eva Malmström; Mats Johansson; Catarina de Carvalho Esteves; KTH; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Cellulose nanofibril CNF ; copolymer; nanocomposite; coating; reinforcement; interface; Fiber- och polymervetenskap; Fibre and Polymer Science;

    Sammanfattning : Magnifying the nanostructure of wood reveals the features of an extraordinary nanocomposite material. In this nanocomposite, long fibrils of semicrystalline cellulose, with a cross-section in the nanometer range and length up to several micrometers, are embedded in an amorphous matrix made of other polymeric components. LÄS MER