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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.
131

Essays on electricity market reforms : a cross-country applied approach

Erdogdu, Erkan January 2013 (has links)
In the last two decades, more than half of the countries in the world have introduced a reform process in their power industries and billions of dollars have been spent on liberalizing electricity markets around the world. This thesis presents a doctoral research concerned with the cross-country empirical analysis of the electricity market reforms. The thesis is in three-paper format; that is, we present three independent but related stand-alone papers. The first paper focuses on the impact of power market reforms on electricity price-cost margins and industrial/residential price ratios. It investigates this issue by looking at the impact of the electricity industry reforms on residential and industrial electricity price-cost margins and their effect on industrial/residential price ratios. Using panel data from 63 developed and developing countries covering the period 1982–2009, empirical models are developed and analysed. The results suggest that each individual reform step has different impact on price-cost margins and industrial/residential price ratios for each consumer and country group. That is to say, our findings imply that similar reform steps may have different impacts in different countries, which supports the idea that reform prescription for a specific country cannot easily be transferred to another one with similar success. The second paper explores whether the question of why some countries are able to implement more extensive reforms is closely related to the question of why some countries have better institutions than others. It analyses this question by using an empirical econometric model based on Poisson regression with cross-section data covering 51 states in US, 13 provinces in Canada and 51 other countries. The study concludes that both the background of the chairperson and the minister/governor and institutional endowments of a country are important determinants of how far reforms have gone in a country. Considering the fact that ideological considerations, political composition of governments and educational/professional background of leaders have played and will play a crucial role throughout the reform process; the third paper attempts to discover the impact of political economic variables on the liberalization process in electricity markets. It develops and analyses empirical models using panel data from 55 developed and developing countries covering the period 1975–2010. The results suggest that a portion of the differences in the reform experiences of reforming countries in the past three decades can be explained by differences in the political structure, in the ideology of the government and in the professional and educational backgrounds of the political leaders.
132

Monocouches auto‐assemblées et nanostructures de métaux nobles : préparation et application au photovoltaïque / Self‐assembled monolayer and noble metal nanostructures : preparation and application to organic photovoltaics

Dufil, Yannick 06 November 2018 (has links)
Au cours de ce travail, dans une première approche descendante, nous avons étudié la réalisation de cellules solaires multicouches évaporées à base de matériaux organiques : le pentacène et le PTCDI-C5. Nous nous sommes servis de cela pour bâtir des cellules simple jonction bicouches et les caractériser. Ces cellules ont servi de modèle de référence à notre étude et démontrent des capacités en accord avec la littérature. Nous avons ensuite produit et caractérisé des cellules multijonctions en bicouches. Une rapide étude sur le comportement d’une couche d’argent d’épaisseur nanométrique a servi à déposer la couche de recombinaison de ces cellules. Nous nous sommes ensuite attelés à la réalisation de monocouches auto-assemblées sur silicium dans le but de développer des couches actives donneur-accepteur et de pouvoir les empiler par l’approche ascendante. Après avoir étudié les groupements d’accroche silanes et acides phosphoniques, nous avons investigué la réalisation de SAM de (3-Triméthoxysilylpropyl) diéthylènetriamine (DETAS) sur silicium en tant que couche d’accroche pour les molécules actives. Nous avons mis en évidence la présence de liaisons hydrogènes aidant à l’organisation de la SAM grâce à des analyses ATR-FTIR. Nous nous sommes servis de cette SAM comme couche d’accroche pour la greffe d’une molécule photo-active le pérylène tétracarboxylique dianhydride (PTCDA). Les techniques de caractérisation par AFM, ellipsométrie et spectroscopie Raman nous ont servi à caractériser notre surface après la greffe de PTCDA / During this study, in a first top-down approach, we investigated evaporated multilayer organic solar cells built from pentacene and PTCDI-C5. We studied spectral response from these materials as well as their vacuum deposition characteristics. We used that knowledge to build simple junction and bi-layer solar cells. Those cells were the reference that allowed us to build and characterised multijonctions bi-layer solar cells with a nanostructured silver layer as recombination layer. A simple study of that silver layer was also conducted. We then switched to self-assembled monolayers on silicon in order to build donor-acceptor active layers that could be stacked, in a bottom-up approach. First, we compared silane and phosphonic acid grafting groups with an 18 carbon long alkane chain. Then we studied (3- trimethoxysilylpropyl) diethylentrimaine (DETAS) on silicon with extra care on relative humidity as a grafting parameter. We also investigated DETAS SAM to highlight hydrogen bonding within the monolayer using ATR-FTIR. DETAS SAM were then used as an anchor molecule for a photoactive molecule perylene tetracarboxylicdianhydrid (PTCDA). Characterisation technics used were AFM, ellipsometry, and Raman spectroscopy

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