Sökning: "Electric dipole"

Visar resultat 1 - 5 av 43 avhandlingar innehållade orden Electric dipole.

1. 1. Analysis of Dipole and Patch Antennas in Cylindrical Structures

   Författare :Peter Slättman; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Fourier transform; cross-section; patch; slot; arbitrary; EFIE; trough guide; cylindrical; dipole; moment method; antenna; aperture coupled;

   Sammanfattning : This thesis deals with the analysis of dipoles, patches, and aperture coupled patches located in an infinitely long cylindrical structure with arbitrary cross-section. The analysis exploits the two-dimensional nature of the structure by expanding all fields and currents in spatial harmonics along the cylinder axis, and solving the subsequent spectral two-dimensional problems by the moment method. LÄS MER

3. 2. Water in and on ionic materials : Structure, energetics, and vibrations

   Författare :Getachew Kebede; Kersti Hermansson; Marie-Pierre Gaigeot; Uppsala universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; DFT; dispersion interactions; OH stretching frequency; electric field; dipole moment; Hydrogen bond; ionic surfaces; ionic hydrates;

   Sammanfattning : Many chemical and physical phenomena in nature, in industrial processes, and in our daily lives take place at water/solid interfaces. The aim of this thesis is to further our knowledge of such processes at a molecular level. LÄS MER

4. 3. Theoretical and Biochemical : Advancing Protein Structure Investigations with Complementing Computations

   Författare :Maxim N. Brodmerkel; Erik G. Marklund; Carl Caleman; Charlotte Uetrecht; Helmut Grubmüller; Uppsala universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Molecular dynamics simulation; Protein structure; Structural biology; Protein hydration; Electric dipole; Collision Induced Unfolding;

   Sammanfattning : Life as we know it today would not exist without proteins. The functions of proteins for us and other organisms are linked to their three-dimensional structures. As such, protein structure investigations are a crucial contribution for understanding proteins and the molecular basis of life. LÄS MER

5. 4. Moment Method Analysis of Antennas on Cylindrical Structures by Using G2DMULT and Design of Hat Fed Reflector Antennas

   Författare :Jian Yang; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; G2DMULT; reflector antenna; paraboloid; dipole; base station antenna; screw heads; vertex plate; self impedance; G1DMULT; ring-shaped phase center; radiation efficiency; FDTD; cylindrical structures; V2D; ring-focus; moment method;

   Sammanfattning : This thesis deals with two aspects of research interest: moment method analysis of antennas on cylindrical structures by using G2DMULT, and design of hat fed reflector antennas. Both of them are two-dimensional (2D) structure problems, one being cylindrical and the other rotationally symmetric. LÄS MER

7. 5. Stark Spectroscopy, Lifetimes and Coherence Effects in Diatomic Molecular Systems

   Författare :Annie Hansson; Peder Royen; Michel Herman; Stockholms universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; diatomic; dipole moment; Stark effect; lifetimes; transition moment; coherence effects; EIT; Autler-Townes; Chemical physics; Kemisk fysik;

   Sammanfattning : In this dissertation is exemplified how different laser based methods are applied in high-resolution spectroscopic studies of internal properties of diatomic molecules.A molecular beam apparatus assembly is described, where a laser ablation source is combined with a time-of-flight mass spectrometer. LÄS MER