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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.
121

Fabrication of gold nanoparticle array on micro-nano structrued self-assembled monolayers / 自己集積化単分子膜の微細加工と金ナノ粒子アレイ構築

Yang, Jeong Hyeon 26 March 2012 (has links)
Kyoto University (京都大学) / 0048 / 新制・課程博士 / 博士(工学) / 甲第16851号 / 工博第3572号 / 新制||工||1540(附属図書館) / 29526 / 京都大学大学院工学研究科材料工学専攻 / (主査)教授 杉村 博之, 教授 酒井 明, 准教授 鈴木 基史 / 学位規則第4条第1項該当
122

Violet Archer’s “The Twenty-Third Psalm” (1952): An Analytical Study of Text and Music Relations through Fibonacci Numbers, Melodic Contour, Motives, and Piano Accompaniment

Wan, Jessica J January 2012 (has links)
This study explores text and music relations in Canadian composer Violet Archer’s “The Twenty-Third Psalm” by analysing the text of Psalm 23, Fibonacci numbers, melodic contours, motives, and the role of the accompaniment. The text focuses on David’s faith in God and his acceptance of God as his shepherd on earth. The four other approaches allow us to examine the work on three different structural levels: background through Fibonacci numbers, middleground through melodic contour analysis, and foreground through motivic analysis and the role of the accompaniment. The measure numbers that align with Fibonacci numbers overlap with some of the melodic contour phrases, which are demarcated by rests, as well as with the most important moments at the surface level, such as the emphasis on the word “death” through recurring and symbolic motives. The piano accompaniment further supports these moments in the text.
123

Rtuťové elektrody jako nástroje pro voltametrické stanovení biologicky aktivních organických látek a pro detekci jejich interakce s DNA / Mercury Electrodes as Tools for Voltammetric Determination of Biologically Active Organic Compounds and for Detection of Their Interaction with DNA

Horáková, Eva January 2016 (has links)
The main aim of this work was to use traditional mercury electrodes for the development of voltammetric methods of determination of organic xenobiotics and for the electrochemical study of the interaction between double-stranded deoxyribonucleic acid (DNA) and these compounds. In relation to my previous research work (conducted in the framework of my diploma thesis), firstly, 4-nitrobiphenyl (4-NBP), the suspected carcinogen, was studied. Interaction of DNA with 4-NBP was studied using differential pulse voltammetry (DPV), cyclic voltammetry (CV), and chronocoulometry at a hanging mercury drop electrode (HMDE), and using CV and alternating current voltammetry at a DNA modified HMDE. Using CV, the reduction mechanism was investigated. The interaction of DNA with 4-aminobiphenyl (4-ABP), a metabolite of 4-NBP, and 4-NBP reduction intermediates was studied. It was found that the interaction of DNA with 4-NBP or 4-ABP results in a formation of a DNA aggregate with these analytes. The second studied analyte was methyl violet 2B (MV). For determination of MV in a buffered solution were used: direct current tast polarography and differential pulse polarography at a dropping mercury electrode, and direct current voltammetry, DPV, and differential pulse adsorptive stripping voltammetry (DPAdSV) at HMDE. The...
124

Metodoptimering för Luxol Fast Blue med kresylviolett på hjärnvävnad / Method optimization for Luxol Fast Blue with cresyl violet on brain tissue

Truong, Freddy January 2022 (has links)
Hjärnan innehåller bland annat neuroner och glia celler. Soma där nukleus samt nissl substans påträffas samt axon som isoleras av myelin anträffas i en neuron. Genom färgningen Luxol Fast Blue (LFB) med kresylviolett färgas myelinet blått av LFB och cellkärnor samt nissl substans rosa-violett av kresylviolett. Syftet med studien var att optimera Luxol Fast Blue med kresylviolett infärgningsmetoden på hjärnvävnad med avseende på koncentration, mängd tillsatt 10 % ättiksyra och därmed pH, färgning i värme samt undersöka kresylviolett-lösningens hållbarhet. Från färgningen graderades LFB intensiteten, kresylviolett intensiteten samt bakgrunds infärgning av kresylviolett från 0-3 där 0 ansågs en negativ infärgning, 1 en svag infärgning, 2 en måttlig infärgning och 3 en stark infärgning. Infärgningen optimerades genom en ökning av kresylviolett koncentrationen där koncentrationen 0,05 % ansågs optimalt. En tillsatt mängd av 10 % ättiksyra tills pH:et når 3,3-3,4 konkluderades även vara optimalt. 0,05 % kresylviolett-lösningen visades även kunna återanvändas i åtminstone 5 veckor, men troligtvis längre, och färgningen med kresylviolett-lösningen bör ske i rumstemperatur. / The brain contains, among other things, neurons and glial cells. Soma where nucleus and nissl substance are found and axon isolated by myelin is found in a neuron. Through the staining Luxol Fast Blue (LFB) with cresyl violet, the myelin is colored blue by LFB and cell nuclei as well as nissl substance pink-violet by cresyl violet. The purpose of the study was to optimize Luxol Fast Blue with the cresyl violet staining method on brain tissue with respect to concentration, amount of added 10 % acetic acid and thus pH, dyeing in heat and to investigate the durability of the cresyl violet solution. From the staining, the LFB intensity, the cresyl violet intensity and the background staining of cresyl violet were graded from 0-3 where 0 was considered a negative staining, 1 a weak staining, 2 a moderate staining and 3 a strong staining. The staining was optimized by an increase in the cresyl violet concentration where the concentration of 0,05 % was considered optimal. An added amount of 10 % acetic acid until the pH reaches 3,3-3,4 was also concluded to be optimal. The 0,05 % cresyl violet solution was also shown to be reusable for at least 5 weeks, but probably longer, and the staining with the cresyl violet solution should take place at room temperature.
125

Oberflächenverstärkte Hyper-Raman-Streuung (SEHRS) und oberflächenverstärkte Raman-Streuung (SERS) für analytische Anwendungen

Gühlke, Marina 02 August 2016 (has links)
Hyper-Raman-Streuung folgt anderen Symmetrieauswahlregeln als Raman-Streuung und profitiert als nicht-linearer Zweiphotonenprozess noch mehr von verstärkten elektromagnetischen Feldern an der Oberfläche plasmonischer Nanostrukturen. Damit könnte die oberflächenverstärkte Hyper-Raman-Streuung (SEHRS) praktische Bedeutung in der Spektroskopie erlangen. Durch die Kombination von SEHRS und oberflächenverstärkter Raman-Streuung (SERS) können komplementäre Strukturinformationen erhalten werden. Diese eignen sich aufgrund der Lokalisierung der Verstärkung auf die unmittelbare Umgebung der Nanostrukturen besonders für die Charakterisierung der Wechselwirkung zwischen Molekülen und Metalloberflächen. Ziel dieser Arbeit war es, ein tieferes Verständnis des SEHRS-Effekts zu erlangen und dessen Anwendbarkeit für analytische Fragestellungen einzuschätzen. Dazu wurden SEHRS-Experimente mit Anregung bei 1064 nm und SERS-Experimente mit Anregung bei derselben Wellenlänge sowie mit Anregung bei 532 nm - für eine Detektion von SEHRS und SERS im gleichen Spektralbereich - durchgeführt. Als Beispiel für nicht-resonante Anregung wurden die vom pH-Wert abhängigen SEHRS- und SERS-Spektren von para-Mercaptobenzoesäure untersucht. Mit diesen Spektren wurde die Wechselwirkung verschiedener Silbernanostrukturen mit den Molekülen charakterisiert. Anhand von beta-Carotin wurden Einflüsse von Resonanzverstärkung im SEHRS-Experiment durch die gleichzeitige Anregung eines molekularen elektronischen Übergangs untersucht. Dabei wurde durch eine Thiolfunktionalisierung des Carotins eine intensivere Wechselwirkung mit der Silberoberfläche erzielt, sodass nicht nur resonante SEHRS- und SERS-Spektren, sondern auch nicht-resonante SERS-Spektren von Carotin erhalten werden konnten. Die Anwendbarkeit von SEHRS für hyperspektrale Kartierung in Verbindung mit Mikrospektroskopie wurde durch die Untersuchung von Verteilungen verschiedener Farbstoffe auf strukturierten plasmonischen Oberflächen demonstriert. / Hyper-Raman scattering follows different symmetry selection rules than Raman scattering and, as a non-linear two-photon process, profits even more than Raman scattering from enhanced electromagnetic fields at the surface of plasmonic nanostructures. Surface-enhanced hyper-Raman scattering (SEHRS) could thus gain practical importance for spectroscopy. The combination of SEHRS and surface-enhanced Raman scattering (SERS) offers complementary structural information. Specifically, due to the localization of the enhancement to the close proximity of the nanostructures, this information can be utilized for the characterization of the interaction between molecules and metal surfaces. The aim of this work was to increase the understanding of the SEHRS effect and to assess its applicability to answer analytical questions. For that purpose, SEHRS experiments with excitation at 1064 nm and SERS experiments with excitation at the same wavelength, as well as with excitation at 532 nm - to detect SEHRS and SERS in the same spectral region - were conducted. As an example for non-resonant excitation, pH-dependent SEHRS and SERS spectra of para-mercaptobenzoic acid were examined. Based on these spectra, the interaction of different silver nanostructures with the molecules was characterized. beta-Carotene was used to study the influence of resonance enhancement by the excitation of a molecular electronic transition during SEHRS experiments. By the thiol-functionalization of carotene, a more intense interaction with the silver surface was achieved, which enables to obtain not only resonant SEHRS and SERS but also non-resonant SERS spectra of carotene. Hyperspectral SEHRS imaging in combination with microspectroscopy was demonstrated by analyzing the distribution of different dyes on structured plasmonic surfaces.
126

A Treatise on the Geometric and Electronic Structure of Clusters : Investigated by Synchrotron Radiation Based Electron Spectroscopies

Lindblad, Andreas January 2008 (has links)
<p>Clusters are finite ensembles of atoms or molecules with sizes in the nanometer regime (<i>i.e.</i> nanoparticles). This thesis present results on the geometric and electronic structure of homogeneous and heterogeneous combinations of atoms and molecules. The systems have been studied with synchrotron radiation and valence, core and Auger electron spectroscopic techniques.</p><p>The first theme of the thesis is that of mixed clusters. It is shown that by varying the cluster production technique both structures that are close to that predicted by equilibrium considerations can be attained as well as far from equilibrium structures.</p><p>Electronic processes following ionization constitute the second theme. The post-collision interaction phenomenon, energy exchange between the photo- and the Auger electrons, is shown to be different in clusters of argon, krypton and xenon. A model is proposed that takes polarization screening in the final state into account. This result is of general character and should be applicable to the analysis of core level photoelectron and Auger electron spectra of insulating and semi-conducting bulk materials as well.</p><p>Interatomic Coloumbic Decay is a process that can occur in the condensed phases of weakly bonded systems. Results on the time-scale of the process in Ne clusters and mixed Ar/Ne clusters are herein discussed, as well observations of resonant contributions to the process. In analogy to Auger <i>vis-à-vis</i> Resonant Auger it is found that to the ICD process there is a corresponding Resonant ICD process possible. This has later been observed in other systems and by theoretical calculations as well in subsequent works by other groups.</p><p>Delocalization of dicationic valence final states in the hydrogen bonded ammonia clusters and aqueous ammonia has also been investigated by Auger electron spectroscopy. With those results it was possible to assign a previously observed feature in the Auger electron spectrum of solid ammonia.</p>
127

Properties and analysis of dioxin-like compounds in marine samples from Sweden

Lundgren, Kjell January 2003 (has links)
Polychlorinated dibenzo-p-dioxins (PCDDs) and dibenzofurans (PCDFs), and dioxin-like polychlorinated biphenyls (PCBs) have been assigned toxic equivalency factors (TEFs). These compounds are today routinely analysed with sophisticated analytical techniques. In a near future, there might be other dioxinlike compounds such as polychlorinated naphthalenes (PCNs), alkyl-polychlorodibenzofurans (R-PCDFs), and polychlorinated dibenzothiophenes (PCDTs) added to this list of toxic dioxin-like compounds. It is therefore important to have a readiness to analyse these new compounds in environmental samples. In this study, a multi-residue non-destructive analytical method for the analyses of these planar dioxin-like compound classes was developed. The use of HPLC PX-21 carbon column fractionation enabled the separation of interfering PCBs from coplanar PCBs and other planar dioxin-like compounds of interest. The obtained planar fraction containing the dioxin-like compounds was analysed using high-resolution GC-MS. Levels of PCNs in surface sediments and settling particulate matter in the northern Baltic Sea were determined. The concentrations of PCNs in background surface sediments were approximately 1 ng/g dw and the estimated PCN fluxes were similar to the pre-industrial levels determined in Europe. The PCN congener patterns in the surface sediments suggest that the PCNs deposited in the Baltic Sea originate from similar sources. Bioaccumulation of PCNs in a benthic food chain (sediment, amphipod, isopod, and four-horned sculpin) from the Gulf of Bothnia was studied. The results indicated that only a few PCN congeners biomagnified. The highest biomagnification factors (BMFs) were found for 2,3,6,7-substituted congeners and those lacking adjacent hydrogen-substituted carbon atoms. The calculated biota to sediment accumulation factors (BSAFs) showed that the tetra- and penta- CNs exhibited BSAF values higher than one, while BSAFs for the more chlorinated PCNs were less than one. A general difference between the northern and southern parts of the Gulf of Bothnia could be seen in the samples, with the lowest PCN and total PCB concentrations being found in the north and the highest in the south. This gradient is related to distance from the more industrialised and populated regions in the southern parts of Sweden and Finland, and central Europe. Analysis of R-PCDFs in crustacean samples from the Swedish west coast was performed using HRGC-MS/MS. The ΣR-PCDFs in these samples were present at concentrations up to 10 times higher than the ΣPCDFs. The relatively high concentrations of R-PCDFs in the crab samples demonstrate that these compounds bioaccumulate. The fate of a pollutant in the environment and the toxicity of a compound are governed by its physicochemical properties. The information found in a data set of properties can predict a compound’s mode of action. The following physicochemical properties for 87 PCDFs were measured: ultra-violetadsorption, relative retention times on two common gas chromatographic stationary phases, and relative mass spectrometric response factors using EI- and NCI- modes.
128

A Treatise on the Geometric and Electronic Structure of Clusters : Investigated by Synchrotron Radiation Based Electron Spectroscopies

Lindblad, Andreas January 2008 (has links)
Clusters are finite ensembles of atoms or molecules with sizes in the nanometer regime (i.e. nanoparticles). This thesis present results on the geometric and electronic structure of homogeneous and heterogeneous combinations of atoms and molecules. The systems have been studied with synchrotron radiation and valence, core and Auger electron spectroscopic techniques. The first theme of the thesis is that of mixed clusters. It is shown that by varying the cluster production technique both structures that are close to that predicted by equilibrium considerations can be attained as well as far from equilibrium structures. Electronic processes following ionization constitute the second theme. The post-collision interaction phenomenon, energy exchange between the photo- and the Auger electrons, is shown to be different in clusters of argon, krypton and xenon. A model is proposed that takes polarization screening in the final state into account. This result is of general character and should be applicable to the analysis of core level photoelectron and Auger electron spectra of insulating and semi-conducting bulk materials as well. Interatomic Coloumbic Decay is a process that can occur in the condensed phases of weakly bonded systems. Results on the time-scale of the process in Ne clusters and mixed Ar/Ne clusters are herein discussed, as well observations of resonant contributions to the process. In analogy to Auger vis-à-vis Resonant Auger it is found that to the ICD process there is a corresponding Resonant ICD process possible. This has later been observed in other systems and by theoretical calculations as well in subsequent works by other groups. Delocalization of dicationic valence final states in the hydrogen bonded ammonia clusters and aqueous ammonia has also been investigated by Auger electron spectroscopy. With those results it was possible to assign a previously observed feature in the Auger electron spectrum of solid ammonia.
129

Solvent–Solute Interaction : Studied by Synchrotron Radiation Based Photo and Auger Electron Spectroscopies

Pokapanich, Wandared January 2011 (has links)
Aqueous solutions were studied using photoelectron and Auger spectroscopy, based on synchrotron radiation and a liquid micro-jet setup. By varying the photon energy in photoelectron spectra, we depth profiled an aqueous tetrabutylammonium iodide (TBAI) solution. Assuming uniform angular emission from the core levels, we found that the TBA+ ions were oriented at the surface with the hydrophobic butyl arms sticking into the liquid. We investigated the association between ions and their neighbors in aqueous solutions by studying the electronic decay after core ionization. The (2p)−1 decay of solvated K+ and Ca2+ ions was studied. The main features in the investigated decay spectra corresponded to two-hole final states localized on the ions. The spectra also showed additional features, related to delocalized two-hole final states with vacancies on a cation and a neighboring water molecule. These two processes compete, and by comparing relative intensities and using the known rate for the localized decay, we determined the time-scale for the delocalized process for the two ions. We compared to delocalized electronic decay processes in Na+, Mg2+, and Al3+, and found that they were slower in K+ and Ca2+, due to different internal decay mechanisms of the ions, as well as external differences in the ion-solute distances and interactions. In the O 1s Auger spectra of aqueous metal halide solutions, we observed features related to delocalized two-hole final states with vacancies on a water molecule and a neighboring solvated anion. The relative intensity of these feature indicated that the strength of the interaction between the halide ions and water correlated with ionic size. The delocalized decay was also used to investigate contact ion pair formation in high concentrated potassium halide solutions, but no concrete evidence of contact ion pairs was observed. / Felaktigt tryckt som Digital Comprehensive Summaries of Uppsala Dissertations from the Faculty of Science and Technology 726
130

Molecularly imprinted polymers for detection of volatile organics associated with fuel combustion

Ngwanya, Olwethu January 2018 (has links)
Magister Scientiae - MSc (Chemistry) / Pollutants such as polycyclic aromatic hydrocarbons (PAHs) are known for their toxic effects which may lead to the cause of degenerative diseases in both humans and animals. PAHs are widespread in the environment, and may be found in water, food, automotive industry and petrochemical industries to name but a few sources. Literature reports have highlighted industrial workplace exposure to PAHs as a leading cause for development of cancer in workers. Particularly, workers in the petrochemical industry are adversely affected and the incidence of skin and lung cancer in this population group is high. The United States of America in its guidelines developed by environmental protection agency (EPA) has identified 18 PAHs as priority pollutants. Among these are anthracene, benzo[a]pyrene and pyrene which have been selected as the focal point of this study due to their significance in the petrochemical industry. Due to the carcinogenic and mutagenic properties reported in literature for certain PAHs, there have been monitoring procedures taken in most countries around the world. The commonly used analytical methods for the detection of PAHs from industrial samples are high performance liquid chromatography (HPLC) coupled to fluorescence detection, membrane filtration, ozonation and reverse osmosis. Analysis of PAHs from the petrochemical industry is typically performed by HPLC method as well as sono-degredation in the presence of oxygen and hydrogen peroxide.

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