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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
21

Angle-, energy- and position-resolved plasmon resonance coupling between gold nanocrystals. / 金顆粒納米晶中角度、能量和空間位置分辨的表面等離子共振耦合 / Angle-, energy- and position-resolved plasmon resonance coupling between gold nanocrystals. / Jin ke li na mi jing zhong jiao du, neng liang he kong jian wei zhi fen bian de biao mian deng li zi gong zhen ou he

January 2010 (has links)
Shao, Lei = 金顆粒納米晶中角度、能量和空間位置分辨的表面等離子共振耦合 / 邵磊. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2010. / Includes bibliographical references. / Abstracts in English and Chinese. / Shao, Lei = Jin ke li na mi jing zhong jiao du, neng liang he kong jian wei zhi fen bian de biao mian deng li zi gong zhen ou he / Shaolei. / Abstract --- p.1 / 摘要 --- p.iii / Acknowledgement --- p.v / Table of Contents --- p.vii / List of Figures --- p.ix / List of Tables --- p.xiv / Chapter 1. --- Introduction --- p.1 / Chapter 1.1 --- Localized Surface Plasmon Resonances of Noble Metal Nanocrystals --- p.3 / Chapter 1.1.1 --- Dielectric Functions of Noble Metal Nanocrystals --- p.3 / Chapter 1.1.2 --- Absorption and Scattering of Light by Noble Metal Nanoparticles --- p.7 / Chapter 1.2 --- Coupling between Localized Surface Plasmons --- p.14 / Chapter 1.2.1 --- Theoretical Treatments for Plasmon Coupling --- p.14 / Chapter 1.2.2 --- Unique Properties Resulting from Plasmon Coupling --- p.15 / Chapter 1.2.3 --- Applications Based on Plasmon Coupling --- p.17 / Chapter 1.3 --- Outline of Thesis --- p.18 / Chapter 2. --- Growth of Gold Nanocrystals and Characterization Techniques --- p.26 / Chapter 2.1 --- Growth of Gold Nanocrystals --- p.26 / Chapter 2.2 --- Characterization Techniques --- p.29 / Chapter 3. --- Surface Plasmon Coupling in Homodimers of Elongated Gold Nanocrystals --- p.34 / Chapter 3.1 --- Formation of Homodimers of Elongated Gold Nanocrystals --- p.35 / Chapter 3.2 --- Angle-Resolved Plasmon Coupling in Gold Nanorod Dimers --- p.37 / Chapter 3.2.1 --- Experimental Results --- p.39 / Chapter 3.2.2 --- FDTD Calculations --- p.43 / Chapter 3.2.3 --- Dipolar Modeling --- p.49 / Chapter 3.3 --- Effect of the Head Shape on the Plasmon Coupling --- p.57 / Chapter 3.4 --- Summary --- p.60 / Chapter 4. --- Surface Plasmon Coupling in Heterodimers of Gold Nanocrystals --- p.64 / Chapter 4.1 --- Formation of Heterodimers of Gold Nanocrystals --- p.65 / Chapter 4.2 --- Energy-Resolved Plasmon Coupling in Gold Nanorod Heterodimers --- p.67 / Chapter 4.3 --- Position-Resolved Plasmon Coupling in Gold Nanorod-Nanosphere Heterodimers --- p.70 / Chapter 4.3.1 --- Experimental Results --- p.71 / Chapter 4.3.2 --- FDTD Calculations --- p.75 / Chapter 4.4 --- Summary --- p.83 / Chapter 5. --- Summary and Conclusion --- p.87
22

Pixel-referencing phase-sensitive surface plasmon resonance imaging sensor.

January 2011 (has links)
Yu, Tsz Tat. / "December 2010." / Thesis (M.Phil.)--Chinese University of Hong Kong, 2011. / Includes bibliographical references (leaves 143-147). / Abstracts in English and Chinese. / Abstract --- p.2 / 摘要 --- p.4 / Acknowledgements --- p.5 / List of Figures --- p.6 / List of Tables --- p.12 / List of Abbreviations --- p.13 / Table of Contents --- p.14 / Chapter Chapter 1 --- Introduction --- p.17 / Chapter Chapter 2 --- Literature Review / Chapter 2.1 --- Surface Plasmon Wave --- p.19 / Chapter 2.2 --- Excitation of Surface Plasmon --- p.23 / Chapter 2.3 --- Surface Plasmon Coupling --- p.24 / Chapter 2.4 --- Surface Plasmon Resonance Detection Techniques --- p.33 / Chapter 2.5 --- Applications of SPR biosensors --- p.39 / Chapter Chapter 3 --- Theory of irradiance modulator / Chapter 3.1 --- Polarization --- p.44 / Chapter 3.2 --- Optical polarizer --- p.45 / Chapter 3.3 --- Liquid Crystal Modulator --- p.49 / Chapter 3.4 --- Irradiance Modulator --- p.52 / Chapter Chapter 4 --- LCM characterization / Chapter 4.1 --- Single LCM Transmittance driven by pure square wave --- p.66 / Chapter 4.2 --- Single LCM Reflectance driven by 50:50 STAM wave --- p.70 / Chapter 4.3 --- Multiple LCMs Reflectance driven by 90:10 STAM wave --- p.73 / Chapter Chapter 5 --- Background of phase measurement / Chapter 5.1 --- From holography to shearography --- p.77 / Chapter 5.2 --- From static Mach-Zehnder interferometer to differential-phase Mach-ZehnderZ interferometer --- p.81 / Chapter 5.3 --- From differential-phase imaging to pixel-referencing imaging --- p.86 / Chapter Chapter 6 --- Pixel-referencing data processing / Chapter 6.1 --- Background --- p.89 / Chapter 6.2 --- Procedures --- p.94 / Chapter 6.3 --- Experimental results --- p.98 / Chapter 6.4 --- Sensor resolution --- p.116 / Chapter 6.5 --- Performance comparison between single-beam LCM and Mach Zehnder configuration --- p.119 / Chapter Chapter 7 --- Discussions / Chapter 7.1 --- Experiment precautions --- p.136 / Chapter 7.2 --- Linear curve fitting --- p.137 / Chapter 7.3 --- Hardware limitation: Low frame rate --- p.138 / Chapter 7.4 --- Matching oil and glass slide --- p.139 / Chapter Chapter 8. --- Conclusions --- p.141 / References --- p.143 / Appendix / Chapter A1 --- "Concentration, Refractive Index and Dielectric constant of Sodium Chloride Solution (20°C)" --- p.148 / Chapter A2 --- Liquid Crystal Modulator Specification --- p.149 / Chapter A3 --- "Digital-to-analogue Converter Device (NI, PCI6036E) Datasheet" --- p.150 / Chapter A4 --- "CCD Camera (Lumenera, Infinity) Datasheet" --- p.151 / Chapter A5 --- Flow chart of SPR phase extraction --- p.152 / Chapter A6 --- Codes of SPR phase extraction in modules --- p.153
23

Analysis of Enzymatic Degradation of Cellulose Microfibrils by Quantitative Surface Plasmon Resonance Imaging

Reiter, Kyle 14 December 2012 (has links)
Cellulose is the most plentiful biopolymer on the planet, and as such, is a large potential energy source. Converting cellulose into ethanol first requires the disruption of the crystallinity of cellulose fibers and subsequent hydrolysis into glucose. The glucose can then be fermented, producing ethanol. The conversion of cellulose fibers to glucose is an energy intensive and costly step, which is a barrier to industrial production of cellulosic ethanol. The use of enzymes to facilitate this conversion is a promising approach. In the present study, the action of individual enzymes and combinations of enzymes from the Hypocrea jecorina secretome on bacterial cellulose fibers has been studied, to better understand their individual and synergistic action. I have used a custom Surface Plasmon Resonance imaging (SPRi) device to measure changes in the thickness of cellulose fiber coverage of a thioglucose-functionalized gold substrate upon exposure to enzymes. The cellulose fibers were deposited using a Langmuir-Blodgett technique, resulting in non-uniform cellulose coverage of the substrate. By defining local Regions of Interest (ROIs) of the cellulose-covered gold film, and by measuring the SPR curves at elevated temperature for the ROIs as a function of time, we are able to determine the rate and extent of degradation of the cellulose fibers within individual ROIs. We have fit the change in SPR angle over time after exposure to enzyme to an exponential decay function that allows us to determine the average time constant of action of these enzymes on the deposited cellulose fibers. We have used the above procedure to measure the average time constants of action and the average degradation fraction (the change in average thickness divided by the initial average thickness) of cellulose fibers exposed to CBH-1, CBH-2, and EG-1, as well as combinations of these enzymes. We have measured an increase in the average degradation fraction and a decrease in the average time constants of action for cellulose fibers exposed to 23 μg/mL CBH-2 compared to fibers exposed to the same concentration of CBH-1. Additionally, for concurrent exposure of CBH-1 and EG-1 (with individual concentrations of 23 μg/mL), as well as concurrent introduction of CBH-1, CBH-2 and EG-1, we observed increases in the average degradation fraction and decreases in average time constants relative to the values measured for the individual enzymes. These measurements allow us to determine the relative activity of these enzymes and they demonstrate cooperativity and complementarity of action of the different enzymes.
24

Plasmon resonance coupling as a tool for detecting epidermal growth factor receptor expression in cancer

Aaron, Jesse Scott, January 1900 (has links)
Thesis (Ph. D.)--University of Texas at Austin, 2007. / Vita. Includes bibliographical references.
25

Optical manipulation using planar/patterned metallo-dielectric multilayer structures : a thesis presented for the degree of Doctor of Philosophy in Electrical and Electronic Engineering at the University of Canterbury, Christchurch, New Zealand /

Lin, Ling, January 1900 (has links)
Thesis (Ph. D.)--University of Canterbury, 2008. / Typescript (photocopy). "January, 2008." Includes bibliographical references (p. 179-206). Also available via the World Wide Web.
26

An examination of the kintetic [sic], structural, and biological effects of zinc on lactogenic cytokine interaction with the human prolactin receptor

Voorhees, Jeffrey L., January 2008 (has links)
Thesis (Ph. D.)--Ohio State University, 2008. / Title from first page of PDF file. Includes vita. Includes bibliographical references (p. 110-118).
27

Effects of the adenosine A2A receptor C-terminus on ligand binding, stability, and downstream signaling

January 2019 (has links)
archives@tulane.edu / G protein-coupled receptors (GPCRs) are the largest family of proteins in humans and are expressed widely throughout the body. GPCRs consist of seven-transmembrane helices that bind extracellular ligands to initiate intracellular downstream signaling via interaction with G proteins, and function in many short and long-term responses in the body, including taste, immune function, and sugar sensing. Extracellular binding and the coupled downstream signaling pathway means that GPCRs are ideal drug targets for many diseases, making them of great interest to the pharmaceutical industry. Some GPCRs have been crystallized in an effort to better elucidate the structure-function relationship to aid in the design of novel therapeutics. The adenosine A2A receptor (A2AR) is a GPCR that has been crystallized bound to agonist, antagonist, and G protein. Although these crystal structures are informative in regards to A2AR structure when associated with binding partners, all current crystal structures truncate nearly 100 amino acids of the C-terminus. As a crystallization strategy, this truncation makes sense considering the C-terminus is long and unstructured. However, truncating roughly 25% of the protein, as well as making other point mutations calls into question the authenticity of the crystal structures in reflecting functional receptor and thus their potential value for therapeutic design. Beyond structural studies, biophysical characterization of drug binding to receptors in vitro to predict efficacy in vivo has shifted away from measures of affinity and selectivity and towards determination of kinetic rates. Kinetic rate constants in combination with affinity and drug residence time are thought to be better predictors of drug behavior in vivo. For these reasons, this thesis focuses on experiments to characterize A2AR kinetic rate constants. Previously, our lab showed that truncating the A2AR C-terminus reduced downstream cAMP signaling in mammalian cells, although where the effect on the signaling pathway occurred was not determined. Here, we report that truncation of the C-terminus ablates receptor association to Gαs, the first step in signaling. In this work, A2AR ligand binding kinetics, stability, and association to Gαs are characterized to better delineate the importance of interactions between receptor and stimuli in a way that is impactful to drug design. / 1 / Kirsten Swonger Koretz
28

Nano-metals plasmonic coupling

Cheng, Ka Ying 12 March 2020 (has links)
In this work, we investigated nano-metal plasmonic coupling between dissimilar metals. We measured the optical transmission of nano-Ag coupled to other nano-metals using glass and Si substrates respectively. The reflected colors shifted from yellow to violet were obtained through the plasmonic coupling with nearest-neighbor nano-metals such as aluminum, magnesium, and ytterbium nano-metals. They were deposited randomly next to the nano-Ag. The metal size is from 8 to 15 nanometers. The results show that the colors changing is essentially due to plasmonic coupling between nano-Ag and another the nano-metals e.g. nano-Al The coupling caused a red shift in plasmonic resonance frequency, thus, changing the reflection color. The resonance shift agrees well with the simulation result using COMSOL. The inter-particle distance and particle size dependency of the optical spectra correspond to surface plasmon resonance extinction peaks for isolated nano-Ag and coupled with those neighboring nano- metals. Due to plasmonic coupling between nanoparticles in small space can create new resonances; red shifts as the interparticle distance reduce. Wavelengths are tuned by the extent of the interparticles interactions which relate to the particles size, interparticles distance and the similarity of nano metals. Using different nano metals to fabricate thin films can change the plasmonic resonance frequency which makes the reflected colours become multihued. When we look into the effect of the nano-particle size, and the distance between nano-particles, we discovered that larger nano-particle size has larger distance between the particles, and since the plasmonic coupling is a function of Inverse Square of the distance between particles. Therefore, smaller nano-particles have the strongest plasmonic coupling. Al produced the smallest nano-particle therefore it has the shortest distance between nano-Al and nano-Ag. Since the size of the particles can be controlled during deposition, the color changing of nano-Ag can be well defined. Thus tunable color changing devices can be fabricated
29

Development of a New Plasmonic Transducer for the Detection of Biological Species

Laffont, Emilie 25 January 2024 (has links)
During the COVID-19 outbreak, PCR tests were widely used for large-scale testing and screening. Yet, this technique requires bulky and time-consuming procedures to prepare the samples collected from the patients before their analysis by well-trained experts with expensive and specific equipment. PCR is therefore not competitive as a technique of detection for a widespread and rapid use in point-of-care sites. Thus, the COVID-19 pandemic highlighted the need for cheap and easy-to-implement biosensors. Surface plasmon resonance based sensors were suggested as a promising alternative in recent years. Indeed, they enable real-time and label-free detection of a wide range of analytes. That explains their widespread use in various fields of applications such as pharmacology, toxicology, food safety, and diagnosis. This thesis proposes and demonstrates a new plasmonic configuration of detection, which can address challenges posed by point-of-care settings. The gratings used as transducers in this configuration were fabricated based on laser interference lithography combined with a nanoimprinting process. The responses of these nanostructures interrogated by a p-polarized light beam result in a transfer of energy between two diffracted orders over an angular scan. This optical phenomenon termed as “optical switch”, was theoretically and experimentally investigated and optimized. The principle of detection based on this specific configuration was demonstrated for the detection of small variations in the bulk refractive index with solutions comprised of different ratios of de-ionized water and glycerol. A limit of detection in the range of 10−6 RIU was achieved. In addition, preliminary bio-assays obtained by combining this configuration with a functionalization are presented and demonstrate the selectivity and the potential of this new plasmonic configuration for biosensing applications. This thesis work paves the way for the use of the optical switch configuration as a biosensor aligned with low-cost manufacturing and relevant for diagnosing in point-of-care sites.
30

Design and verification of a surface plasmon resonance biosensor

Sommers, Daniel R. 18 August 2004 (has links)
The Microelectronics Group has been researching sensors useful for detecting and quantifying events in biological molecular chemistry, for example, binding events. Our previous research has been based primarily on quartz resonators. This thesis describes the results of our initial research of Surface Plasmon Resonance (SPR) based technology. This study contains the design and implementation of a fully functional SPR biosensor with detailed disclosure of monolayer construction, digital hardware interfaces and software algorithms for process the SPR sensors output. An antibody monolayer was constructed on the biosensor surface with the goal of setting the strengths, weaknesses and limitation of measuring molecular events with SPR technology. We documented several characteristics of molecular chemistry that directly effect any measurements made using Surface Plasmon Resonance technology including pH, free ions, viscosity and temperature. Furthermore, the component used in our study introduced additional limitations due to wide variations amongst parts, the constraint of a liquid medium and the large surface area used for molecular interrogation. We have identified viable applications for this sensor by either eliminating or compensating for the factors that affect the measured results. This research has been published at the inaugural IEEE sensors conference and to our knowledge is the first time a biosensor has been constructed by attaching a sensor to a PDA and performing all signal processing, waveform analysis and display in the PDAs core processor.

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