Sökning: "Surface impedance"

Visar resultat 1 - 5 av 108 avhandlingar innehållade orden Surface impedance.

  1. 1. Electric Fields for Surface Design and Chemical Analysis

    Författare :Christian Ulrich; Fredrik Björefors; Ingemar Lundström; Tautgirdas Ruzgas; Linköpings universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Electric fields; Surface design; Chemical analysis; Bipolar electrodes; Impedance spectroscopy; Electrochemistry; Elektrokemi; Chemical physics; Kemisk fysik; Physical chemistry; Fysikalisk kemi; Surface and colloid chemistry; Yt- och kolloidkemi;

    Sammanfattning : This thesis deals with the use of electric fields for evaluation and control of chemical systems. An electric field can result in the flow of charge across an interface between a metal and a solution, by means of chemical reactions. This interplay between electricity and chemistry, i.e. LÄS MER

  3. 2. Integration of Surface Acoustic Wave and Microfluidic Technologies for Liquid-Phase Sensing Applications

    Författare :Kiryl Kustanovich; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; IDE; Resonator; SH-SAW; Impedance Spectroscopy; Surface Acoustic Wave; PDMS; LiNbO3; Microfluidics; Sensor;

    Sammanfattning : This thesis discusses a new concept for construction of a novel SAW in-liquid sensor employing surface acoustic wave resonance (SAR) in a one-port configuration. In this concept, the reflective gratings of a one-port SAW resonator are employed as mass loading-sensing elements, while the SAW transducer is protected from the measurement environment, reducing power losses significantly. LÄS MER

  4. 3. Device Technology Based on High Temperature Superconductors and Microwave Breakdown in Gases

    Författare :Martin Löfgren; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; distortion; penetration depth; surface resistance; transmit-receive switch; coupled-grain model; high-power; microwave; pulse; surface impedance; breakdown; propagation; modulator; air; superconductor; transmission line; resonator; coplanar waveguide; plasma;

    Sammanfattning : This thesis deals with two separate fields of microwave technology. The first section treats microwave characterization and applications of high temperature superconducting (HTS) thin films, while the second section treats microwave breakdown in transmit-receive (TR) switches and in air. Within the first section, four main topics are adressed. LÄS MER

  5. 4. Surface Phenomena in Li-Ion Batteries

    Författare :Anna Andersson; Rachid Yazami; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Chemistry; Li-ion batteries; graphite; surface films; non-aqueous electrolytes; thermal stability; salt dependence; Kemi; Chemistry; Kemi; Inorganic Chemistry; oorganisk kemi;

    Sammanfattning : The formation of surface films on electrodes in contact with non-aqueous electrolytes in lithium-ion batteries has a vital impact on battery performance. A basic understanding of such films is essential to the development of next-generation power sources. LÄS MER

  7. 5. Investigation of electrochemical properties and performance of stimulation/sensing electrodes for pacemaker applications

    Författare :Anna Norlin; Jinshan Pan; Dieter Scharnweber; KTH; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Physical chemistry; pacemaker electrode; interfacial property; biomaterial; electrostimulation charge transfer mechanism; electrochemical impedance spectroscopy; transient processes; plasma electrolysis anodisation; porous niobium oxide; ruthenium oxide; nano-porous carbon; iridium oxide; titanium nitride; platinum; surface roughness; porous electrode; pacing impedance; electrode polarisation; Fysikalisk kemi; Physical chemistry; Fysikalisk kemi;

    Sammanfattning : People suffering from certain types of arrhythmia may benefit from the implantation of a cardiac pacemaker. Pacemakers artificially stimulate the heart by applying short electrical pulses to the cardiac tissue to restore and maintain a steady heart rhythm. By adjusting the pulse delivery rate the heart is stimulated to beat at desired pace. LÄS MER