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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.
1

PROPRIÉTÉS ÉLECTRONIQUES DU GRAPHITE

Schneider, Johannes M. 26 October 2010 (has links) (PDF)
Dans cette thèse le magnétotransport à basse température (T = 10 mK) et l'effet de Haas-van Alphen sont examinés pour le graphite naturel et le graphite HOPG. Dans la première partie, le magnétotransport au champ magnétique jusqu'à B = 11 T est présenté. Une analyse de Fourier du signal après soustraction du fond de magnétorésistance montre que le transport électrique dans le graphite est dominé par deux types de porteurs avec des fréquences et phases en accord avec le modèle SWM. Nous confirmons la validité du modèle SWM par des calculs détaillés de la structure de bande en champ magnétique. Le mouvement de l'énergie de Fermi pour B > 2 T est calculé d'une manière auto-cohérente en supposant que la somme des concentrations des électrons et des trous est constante. Des mesures sous champs magnétiques intenses (0 < B < 28 T) sont employées pour étudier l'effet Zeeman et la phase de l'onde de densité de charge. En ce qui concerne l'effet Zeeman, les calculs SWM incluant le mouvement de l'énergie de Fermi nécessitent un facteur de Lande g = 2.5 pour reproduire la séparation de spin des motifs dans les données. Les mesures de l'onde de charge de densité confirment que le champ magnétique auquel l'onde de charge de densité apparait est lie a la température par une formule de type Bardeen-Cooper-Schrieffer (BCS). Des mesures de l'effet de Haas-van Alphen confirment les résultats obtenus par de magnétotransport à bas champ.
2

PROPRIÉTÉS ÉLECTRONIQUES DU GRAPHITE

Schneider, Johannes M. 26 October 2010 (has links) (PDF)
Dans cette thèse le magnétotransport à basse température (T = 10 mK) et l'effet de Haas-van Alphen sont examinés pour le graphite naturel et le graphite HOPG. Dans la première partie, le magnétotransport au champ magnétique jusqu'à B = 11 T est présenté. Une analyse de Fourier du signal après soustraction du fond de magnétorésistance montre que le transport électrique dans le graphite est dominé par deux types de porteurs avec des fréquences et phases en accord avec le modèle SWM. Nous confirmons la validité du modèle SWM par des calculs détaillés de la structure de bande en champ magnétique. Le mouvement de l'énergie de Fermi pour B > 2 T est calculé d'une manière auto-cohérente en supposant que la somme des concentrations des électrons et des trous est constante. Des mesures sous champs magnétiques intenses (0 < B < 28 T) sont employées pour étudier l'effet Zeeman et la phase de l'onde de densité de charge. En ce qui concerne l'effet Zeeman, les calculs SWM incluant le mouvement de l'énergie de Fermi nécessitent un facteur de Lande g = 2.5 pour reproduire la séparation de spin des motifs dans les données. Les mesures de l'onde de charge de densité confirment que le champ magnétique auquel l'onde de charge de densité apparait est lie a la température par une formule de type Bardeen-Cooper-Schrieffer (BCS). Des mesures de l'effet de Haas-van Alphen confirment les résultats obtenus par de magnétotransport à bas champ.
3

Using GIS in Solid Waste Management Planning : A case study for Aurangabad, India

Shaikh, Moiz Ahmed January 2006 (has links)
<p>Waste management is a global environmental issue which concerns about a very significant problem in today’s world. There is a considerable amount of disposal of waste without proper segregation which has lead to both economic and environment sufferings. It is still practiced in many cities. There is a tremendous amount of loss in terms of environmental degradation, health hazards and economic descend due to direct disposal of waste. It is better to segregate the waste at the initial stages where it is generated, rather than going for a later option which is inconvenient and expensive. There has to be appropriate planning for proper waste management by means of analysis of the waste situation of the area.</p><p>This paper would deal with, how Geographical Information System can be used as a decision support tool for planning waste management. A model is designed for the case study area in an Indian city for the purpose of planning waste management. The suggestions for amendments in the system through GIS based model would reduce the waste management workload to some extent and exhibit remedies for some of the SWM problems in the case study area. The waste management issues are considered to solve some of the present situation problems like proper allocation and relocation of waste bins, check for unsuitability and proximity convenience due to waste bin to the users, proposal of recyclable waste bins for the required areas and future suggestions. The model will be implemented on the Aurangabad city’s case study area data for the analysis and the results will suggest some modification in the existing system which is expected to reduce the waste management workload to a certain extent.</p>
4

Using GIS in Solid Waste Management Planning : A case study for Aurangabad, India

Shaikh, Moiz Ahmed January 2006 (has links)
Waste management is a global environmental issue which concerns about a very significant problem in today’s world. There is a considerable amount of disposal of waste without proper segregation which has lead to both economic and environment sufferings. It is still practiced in many cities. There is a tremendous amount of loss in terms of environmental degradation, health hazards and economic descend due to direct disposal of waste. It is better to segregate the waste at the initial stages where it is generated, rather than going for a later option which is inconvenient and expensive. There has to be appropriate planning for proper waste management by means of analysis of the waste situation of the area. This paper would deal with, how Geographical Information System can be used as a decision support tool for planning waste management. A model is designed for the case study area in an Indian city for the purpose of planning waste management. The suggestions for amendments in the system through GIS based model would reduce the waste management workload to some extent and exhibit remedies for some of the SWM problems in the case study area. The waste management issues are considered to solve some of the present situation problems like proper allocation and relocation of waste bins, check for unsuitability and proximity convenience due to waste bin to the users, proposal of recyclable waste bins for the required areas and future suggestions. The model will be implemented on the Aurangabad city’s case study area data for the analysis and the results will suggest some modification in the existing system which is expected to reduce the waste management workload to a certain extent.
5

Solid waste management based on cost-benefit analysis using the WAMED model

Mutavchi, Viacheslav January 2012 (has links)
Efficient waste management enables the protection of human health, reducing environmental pollution, saving of natural resources, and achieving sustainable and profitable management of energy. In many countries, the general guidelines for waste management are set by national or local waste management plans. Various models provide local authorities with decision-making tools in planning long-term waste management scenarios.This study aims at providing a special model framework for the evaluation of ecological–economic efficiency (ECO-EE) of waste management. This will serve as an information support tool for decision making by actors of a solid waste management (SWM) scheme, primarily at the municipal and regional levels. The objective of this study is to apply the waste management’s efficient decision (WAMED) model along with the company statistical business tool for environmental recovery indicator (COSTBUSTER) model to SWM and municipal solid waste (MSW) schemes in general in order to evaluate and improve their ECO-EE. COSTBUSTER is a mathematical indicator for the size and extent of implementation costs of a certain SWM scheme, compared with the total size of the average financial budget of a SWM actor of a certain kind. In particular, WAMED is proposed for evaluating the suitability to invest in baling technology. Baling of solid waste is an emerging technology which is extensively used worldwide to temporarily store waste for either incineration or recovery of raw materials. The model for efficient use of resources for optimal production economy (the EUROPE model) is for the first time applied to emissions from baling facilities. It has been analysed how cost-benefit analysis (CBA) and full cost accounting (FCA) can facilitate environmental optimisation of SWM schemes. The effort in this work represents a continuation of such ambitions as an enlargement of the research area of CBA based modelling within SWM. In the thesis, certain theoretical and economic aspects of SWM were analysed as case studies. A shift of viewpoints within the field of waste management is presented. This shift is in accordance with the prevailing concept of sustainable development, as commonly understood. It is concluded that in the practical SWM context, the findings of the study point at the possibilities to modify the common CBA- and FCA-based methods by WAMED, COSTBUSTER, and EUROPE. Therefore, it can be said that estimations in a SWM scheme can be carried out by using certain economic model, if properly modified in a logical and plausible way. New principles for cost allocation to SWM residual products are presented in the current work. They imply strong industrial cost saving incentives through promoting the introduction of new and improved processing technologies for rest-waste. Such incentives then strongly promote investments that are likely to improve both the environment and the corporate profitability. Thereby, the occurrence of non-commercialised, and hence not utilized, wastes is reduced. This improves the short term corporate economy through saving raw materials such as solid waste fuel, spending less time for administrating waste flows, and less wear and tear of the plant machinery. Additional environmental advantages which affect the balance sheets in a favourable way are related to the long-term business economy and extended environmental goodwill. This is due to the recently introduced way of considering solid waste as regular goods in financial terms - the equality principle. If waste is seen as goods, and not wasted in landfills, the environment will improve. This, in turn, leads to an improved quality of life. Based on the current study, it is recommended to apply WAMED to SWM schemes in order to evaluate their ECO–EE to justify decision making and investments. Also, it is recommended to apply COSTBUSTER, based on the current WAMED outcome, to SWM schemes to determine their relative size and extent. It is recommended to apply EUROPE to the emissions in case of accidental burning, treatment of leachate, andabatement with odours at any SWM scheme, based on the induced economic incentives, in order to reduce unwanted substances and phenomena.
6

ECONOMIC AND ENVIRONMENTAL IMPACTS OF STORMWATER MANAGEMENT : Case study: Cost-effectiveness evaluation of Proposition O projects

Mahdian, Adrian January 2020 (has links)
Stormwater Management (SWM) or Best management practices (BMPs) treat the stormwater runoff that carries pollutants. Pollutants in the waters and in the stormwater, negatively impact the environment, the ecology, and natural resources. Stormwater Control Measures (SCM) are used in different projects to improve water quality and quantity. This thesis aims to understand the connection between SWMs, the economy, and environmental sustainability. This thesis evaluates the cost-effectiveness of SWMs in Mediterranean climates. The research aims to guide the next project managers to choose better SWMs based on cost-effectiveness, socio-economic, and environmental implications. Various studies suggest that the terms SWM, SWM, and SCM are used interchangeably. The research methodology uses a mix of qualitative and quantitative data analysis The research was conducted in Los Angeles at the request of UCLA. Therefore, it focused on water quality improvement projects in Los Angeles. The costs for the projects, areas, and whatSWMs are used will be acquired through data gathering and personal communication with experts. This thesis compares several projects which include different SWMs. It calculates the cost-effectiveness with two different methods, firstly, the cost per drainage area, and secondly, the cost per pollutant removed. Data is gathered from the city of LA and other secondary data sources to calculate the cost-effectiveness. The calculation results showed that the Glenoaksproject and the Machado lake project were the most cost-effective. Glenoaks utilizes infiltration wells and grass swales, and the Machado lake is a large wetland. Based upon these facts, generally, wetlands and grass swales can be recommended for Mediterranean climates. The expensive total costs of SWMs or their inability to remove pollutants can strongly affect the cost-effectiveness of some projects, and produce a negative impact on the economy. Quantitative assessment of study investigates cost-effectiveness of SWMs and for highlighting its economic impact. For qualitative assessment thematic analysis of 14 sample studies related to stormwater management (SWM) was carried out. Findings reveal that 78% of sample studies reflect the themes associated with the positive economic impact of SWMs. Additionally, the sample studies confirm a 76% positive impact of SWMs on the environment and ecology of the region. Further research with better data and more accurate calculations are needed. It would be beneficial if other factors such as recreation and unquantifiable factors such as the aesthetic improvements and community benefits were incorporated into or considered together with the cost-effectiveness for future projects.
7

Messung und Modellierung der Initiatoreffektivität organischer Peroxide in der Ethen-Hochdruckpolymerisation / Measurement and modelling of the initiator efficiency of organic peroxides in the high-pressure ethene polymerization

Hinrichs, Stefan 30 June 2005 (has links)
No description available.
8

Sternpolymere mittels RAFT-Polymerisation / Star Polymers via RAFT Polymerization

Boschmann, Daniel 28 April 2008 (has links)
No description available.

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