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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

Performance optimisation of HFC refrigerants by experimental and mathematical methods

Yan, Yu January 2002 (has links)
No description available.
2

The development and subsequent deployment of an automated GC-system for monitoring trace atmospheric halocarbons in near-real time

Bassford, Matthew Richard January 1998 (has links)
No description available.
3

Kontroliuojamų užsienio vienetų pajamų apmokestinimo taisyklės Lietuvoje, Jungtinėje Karalystėje ir Vokietijoje / Reglamentation of cfc rules in lithuania, junited kingdom and germany

Lukas, Mindaugas 08 September 2009 (has links)
Šiame magistro darbe nagrinėjamos ir vertinamos Lietuvoje galiojančių kontroliuojamųjų užsienio vienetų pajamų apmokestinimo taisyklių, dar vadinamų CFC taisyklėmis, nuostatos. Būtinybę analizuoti ir tobulinti lietuviškąsias CFC taisykles patvirtina tiek besiformuojanti Europos Teisingumo Tesimo pozicija, vertinant šias taisykles Europos Sąjungos teisės kontekste, tiek itin skurdi CFC taisyklių taikymo praktika Lietuvoje. Pagrindinis darbo tikslas yra išanalizuoti esmines Lietuvoje taikomų CFC taisyklių nuostatas, palyginti jas su analogiškomis nuostatomis Jungtinės Karalystės ir Vokietijos CFC taisyklėse. Taip pat bandoma įvertinti, kiek lietuviškosios CFC taisyklės padeda įgyvendinti joms keliamus tikslus bei pateikti potencialius esamų nuostatų tobulinimo variantus. Darbe nėra pateikiamas idealus ar Lietuvai tinkamiausias kontroliuojamųjų užsienio vienetų pajamų apmokestinimo taisyklių modelis, kadangi tai reikalautų kur kas išsamesnės ir platesnės užsienio valstybių teisės aktų bei praktikos analizės, o tik, įvertinant ir Europos Teisingumo Teismo poziciją išdėstytą byloje C-196/04 Cadbury Schweppes plc & Cadbury Schweppes Overseas Ltd v Commissioners of Inland Revenue, ieškoma galimų esamo teisinio reguliavimo alternatyvų bei, modeliuojant hipotetines situacijas, atskleidžiamos potencialios spragos. Darbo struktūra iš esmės atitinka CFC taisyklių taikymo etapus: pirmiausia analizuojami kontroliuojamojo vieneto identifikavimo kriterijai, aptariami taisyklių netaikymo... [toliau žr. visą tekstą] / This master thesis concerns with Lithuanian CFC rules. The necessity to analyze and improve current Lithuanian CFC legislation first of all is influenced by recent position of European Court of Justice, stated in case Cadbury Schweppes plc & Cadbury Schweppes Overseas Ltd v Commissioners of Inland Revenue, and quite poor practice applying CFC rules in Lithuania. The primary objective of this master thesis is to examine the basic elements of Lithuanian CFC rules and compare them to British and German CFC legislation. There is no purpose to find perfect or the most suitable controlled foreign company legislation for Lithuania, as this would require much wider and deeper analysis of foreign CFC rules and practice, but, regarding ECJ position in above mentioned case, possible alternatives for current Lithuanian CFC rules are examined. The structure of master thesis reflects the basic scheme of CFC rules, common for all countries that apply them: it begins with analysis of the concept of controlled foreign company and exceptions of CFC rules, then the rules for computation of passive income of CFC and apportionment to resident shareholders are assessed, then the taxation of apportioned profits of a CFC and methods of relief to prevent double taxation are discussed. Thesis is concluded by summarizing examined issues and presenting basic guidelines for improvement of current Lithuanian CFC rules.
4

Skatteparadis : Hur fungerar CFC - lagstiftningen som en förebyggande åtgärd? / Tax Havens : How does CFC - legislation work as a preventive arrangement?

Ericsson, Marina January 2008 (has links)
<p>Skatteparadis har funnits i många år. De första trenderna på skatteparadis kan spåras redan från 1960 - talet och det verkar inte finnas något stopp för dess tillväxt. På grund av en alltmer globaliserad värld har kapitalrörelserna frigjorts över nationsgränserna. Likaså har alltfler människor i dag en ökad förmögenhet. Allt detta tillsammans skapar en skattekonkurrens som gör det möjligt för vissa stater, det vill säga skatteparadis, att locka till sig utländska investerare som i vanliga fall inte skulle ha varit så attraktiva om de förmånliga skattevillkoren inte hade funnits.</p><p>Uppsatsens syfte är dels att ge en innebörd av vad skatteparadis innebär, dels att studera vilka aktioner riktade mot skatteparadis det finns samt påvisa hur dessa fungerar som medel. Det sistnämnda syftet är tänkt att ta CFC - lagstift¬ningen i beaktande genom att studera vilken funktion denna har som förebyggande åtgärd mot skatteparadisen.</p><p>För att komma åt problemet med skatteparadis pågår det, hos många organisationer, ett effektivt förebyggande arbete mot dess framväxt. Likaså är det tänkt att CFC - lagstiftningen ska hjälpa till att motverka skatteparadisen på den grunden att lagstiftningen är tänkt att inhemska delägare ska löpande beskattas för lågbeskattade inkomster i utländska juridiska personer. Genom detta ska den skattskyldiga inte kunna undgå beskattning även om de placerar sin förmögenhet i stater med låg beskattning eller till och med ingen beskattning alls.</p><p>Ett bland flera skäl, vilken påverkar att skatteparadis inte kan utplånas helt och hållet, som jag har kommit fram till i uppsatsen är den starka sekretess som råder i skatteparadisstaterna. Genom den starka sekretessen sker det inget effektivt informationsutbyte med länder i andra delar av världen. Detta gör att det bland annat blir svårare att spåra människors samt bolags konton till stater vilka kännetecknas som skatteparadis.</p>
5

Distribution and Modeling of Chlorofluorocarbons in the Northwestern Pacific Ocean

Hwang, Hsing- Chih 17 January 2002 (has links)
Because CFC-11 and CFC-12 are extremely stable and purely anthropogenic and the CFCs enter the ocean through air-sea exchange at the sea surface, they serve as good tracers for studying the oceans. Since CFCs and tritium share similar characteristics such as their anthropogenic production, inertness to biological activities, a tritium box model applied to the North Atlantic Ocean by J. L. Sarmiento in 1983 is used to study the distribution of CFCs in the Northwest Pacific. This thesis attempts to use this model to calculate the past concentrations of CFCs in the atmosphere assuming equilibrium distribution between the surface ocean waters and the atmosphere in the source region of the oceans. The results may allow us to check the history of CFCs in the atmosphere. The data used in this thesis are those reported by NOAA from three cruises: CO2-87 and CGC92 along 165oE and CO2-88 along 170oW, all from 40o to 10oN. This latitude range avoids the complex gyres and the sea-ice which may limit the air-sea exchange in the North, and also avoids the upwelling in the equatorial region. The outcrop of the 26.0 sq water is located at longitude about 52o-53oN along 165oE, but is located at about 40oN along 170oW. The outcrop will move southward in winter. The vertical distribution pattern of CFCs is similar to that of oxygen. Concentrations of CFCs in ocean water increase as potential temperature and salinity decrease. High latitudes of low temperature and salinity have high CFC solubility and high air-sea exchange rates, and are presumably the major areas for input of CFCs into the seawater. As the CFCs in the air increase over the years the concentrations of CFCs in the surface ocean water also increase but decrease with water depth. The solubility, F, of CFCs is a function of both temperature and salinity, but temperature prevails. The F values for CFC-11 and CFC-12 from 10o to 50oN along 165oE are 5.86-16.0 and 1.70-4.15 mmole/kg/ atm, respectively. The values along 170oW are, respectively, 6.60-22.2 and 1.89-5.55 mmole/kg/atm. The solubility of CFC-11 is about four times as large as that of CFC-12. The solubility of CFCs along 170oW is about 1.4 times along 165oE because of temperature and salinity differences. The exchange rate in the time scale for =1 year ranges 0.85-1.3 yr-1, CFC-11 has a mean of 0.99 yr-1, CFC-12 has a mean of about 1.04 yr-1. Along the isopycnal surface of sq=26.0, the highest exchange rate between two boxes is 2.34 yr-1, the lowest 0.06 yr-1. Based on the calculated concentrations of CFCs in the surface seawater from the atmospheric value in the past, apparent ages of the Mode Waters are similar for both CFC-11 and CFC-12. The apparent age along 165oE at 10oN is about 17 years on the defined isocypnal surface, and it is about 15 years along 170oW at 10oN. The spreading rate of CFCs in the Northwest Pacific is thus about 172-221 km/yr. During the 17 years, the annual increase in influx to the seawater is about 0.12 pM/kg/yr for CFC-11, and about 0.059 pM/kg/yr for CFC-12. The error in calculating atmosphere CFCs in the past is about 11 % for CFC-11, and 6 % for CFC-12.
6

Syndrome de Noonan et apparentés Etude clinique et moléculaire de 51 enfants et adultes pris en charge au centre de référence "anomalies de développement" de Nancy /

Piard, Juliette Leheup, Bruno. January 2009 (has links) (PDF)
Thèse d'exercice : Médecine : Nancy 1 : 2009. / Titre provenant de l'écran-titre.
7

Skatteparadis : Hur fungerar CFC - lagstiftningen som en förebyggande åtgärd? / Tax Havens : How does CFC - legislation work as a preventive arrangement?

Ericsson, Marina January 2008 (has links)
Skatteparadis har funnits i många år. De första trenderna på skatteparadis kan spåras redan från 1960 - talet och det verkar inte finnas något stopp för dess tillväxt. På grund av en alltmer globaliserad värld har kapitalrörelserna frigjorts över nationsgränserna. Likaså har alltfler människor i dag en ökad förmögenhet. Allt detta tillsammans skapar en skattekonkurrens som gör det möjligt för vissa stater, det vill säga skatteparadis, att locka till sig utländska investerare som i vanliga fall inte skulle ha varit så attraktiva om de förmånliga skattevillkoren inte hade funnits. Uppsatsens syfte är dels att ge en innebörd av vad skatteparadis innebär, dels att studera vilka aktioner riktade mot skatteparadis det finns samt påvisa hur dessa fungerar som medel. Det sistnämnda syftet är tänkt att ta CFC - lagstift¬ningen i beaktande genom att studera vilken funktion denna har som förebyggande åtgärd mot skatteparadisen. För att komma åt problemet med skatteparadis pågår det, hos många organisationer, ett effektivt förebyggande arbete mot dess framväxt. Likaså är det tänkt att CFC - lagstiftningen ska hjälpa till att motverka skatteparadisen på den grunden att lagstiftningen är tänkt att inhemska delägare ska löpande beskattas för lågbeskattade inkomster i utländska juridiska personer. Genom detta ska den skattskyldiga inte kunna undgå beskattning även om de placerar sin förmögenhet i stater med låg beskattning eller till och med ingen beskattning alls. Ett bland flera skäl, vilken påverkar att skatteparadis inte kan utplånas helt och hållet, som jag har kommit fram till i uppsatsen är den starka sekretess som råder i skatteparadisstaterna. Genom den starka sekretessen sker det inget effektivt informationsutbyte med länder i andra delar av världen. Detta gör att det bland annat blir svårare att spåra människors samt bolags konton till stater vilka kännetecknas som skatteparadis.
8

Ascensão e queda dos CFCs: uma análise de periódicos científicos e de livros didáticos de química ambiental / Rise and fall of CFCs: an analysis of scientific journals and environmental chemistry textbooks

Viana, Helio Elael Bonini 27 August 2013 (has links)
O presente trabalho tem como objetivo investigar os processos de ascensão e queda dos clorofluorocarbonetos (CFCs) como bens de consumo, bem como o desenvolvimento da percepção de risco da comunidade química em relação a esses compostos, que culminou com sua caracterização como agentes de risco ambiental global. Para isso, foi desenvolvido um estudo de caso histórico acerca do uso dos CFCs ao longo do século XX, de solução tecnológica ideal a protagonista de uma inédita dimensão de risco químico. Além disso, foi realizada uma análise de cartas enviadas por leitores, editoriais e resenhas de livros publicadas em cinco periódicos científicos: Chemical & Engineering News, Journal of Chemical Education, Environmental Science and Technology, Nature e Science, no período compreendido entre 1975 e 1991, e de livros didáticos de Química Ambiental publicados entre 1970 e 1995 - período marcado por intenso debate sobre a possibilidade de destruição da camada de ozônio estratosférica. A escolha desses periódicos e livros buscou contemplar diferentes seções da comunidade química, de modo a se ter uma amostra representativa de diferentes formas de pensamento dentro desse amplo espectro profissional que constitui a química. Para análise dessa amostra foi escolhida a Teoria Cultural de Douglas e Wildavsky, a qual descreve quatro visões de mundo que se mostram bastante adequadas para analisar as percepções de risco, as atitudes e os argumentos envolvidos nas discussões da época. Os resultados obtidos apontam para mudanças nas percepções de risco da comunidade química, aproximando-as do Princípio da Precaução para a tomada de decisões, em um período marcado pelo desenvolvimento da Química Ambiental. / This study aims to investigate the processes of rise and fall of chlorofluorocarbons (CFCs) as consumer goods, as well as the development of risk perception regarding these compounds among the chemists community, culminating in its characterization as agents of global environmental risk. A historical case study on the trajectory of CFCs throughout the twentieth century, from ideal technological solution to protagonist of an unprecedented scale chemical risk, was developed. In addition, the study includes an analysis of letters from readers, editorials and book reviews published in five journals: Chemical & Engineering News, Journal of Chemical Education, Environmental Science and Technology, Nature and Science, in the period between 1975 and 1991, and also an analysis of Environmental Chemistry textbooks published between 1970 and 1995 - a period marked by intense debate about the possibility of destruction of the stratospheric ozone layer. The choice of these journals and books sought to include different sections of the chemistry community, in order to get a representative sample of different ways of thinking within the broad professional spectrum of chemistry. Douglas\' and Wildavsky\'s Cultural Theory was selected to analyse this sample. The theory describes four worldviews that seems rather appropriate to analyze risk perceptions, attitudes and arguments involved in the discussions of the time. Results point to changes in chemists\' risk perceptions, which brought them closer to the Precautionary Principle as a guide to decision making in a period marked by the development of Environmental Chemistry.
9

Ascensão e queda dos CFCs: uma análise de periódicos científicos e de livros didáticos de química ambiental / Rise and fall of CFCs: an analysis of scientific journals and environmental chemistry textbooks

Helio Elael Bonini Viana 27 August 2013 (has links)
O presente trabalho tem como objetivo investigar os processos de ascensão e queda dos clorofluorocarbonetos (CFCs) como bens de consumo, bem como o desenvolvimento da percepção de risco da comunidade química em relação a esses compostos, que culminou com sua caracterização como agentes de risco ambiental global. Para isso, foi desenvolvido um estudo de caso histórico acerca do uso dos CFCs ao longo do século XX, de solução tecnológica ideal a protagonista de uma inédita dimensão de risco químico. Além disso, foi realizada uma análise de cartas enviadas por leitores, editoriais e resenhas de livros publicadas em cinco periódicos científicos: Chemical & Engineering News, Journal of Chemical Education, Environmental Science and Technology, Nature e Science, no período compreendido entre 1975 e 1991, e de livros didáticos de Química Ambiental publicados entre 1970 e 1995 - período marcado por intenso debate sobre a possibilidade de destruição da camada de ozônio estratosférica. A escolha desses periódicos e livros buscou contemplar diferentes seções da comunidade química, de modo a se ter uma amostra representativa de diferentes formas de pensamento dentro desse amplo espectro profissional que constitui a química. Para análise dessa amostra foi escolhida a Teoria Cultural de Douglas e Wildavsky, a qual descreve quatro visões de mundo que se mostram bastante adequadas para analisar as percepções de risco, as atitudes e os argumentos envolvidos nas discussões da época. Os resultados obtidos apontam para mudanças nas percepções de risco da comunidade química, aproximando-as do Princípio da Precaução para a tomada de decisões, em um período marcado pelo desenvolvimento da Química Ambiental. / This study aims to investigate the processes of rise and fall of chlorofluorocarbons (CFCs) as consumer goods, as well as the development of risk perception regarding these compounds among the chemists community, culminating in its characterization as agents of global environmental risk. A historical case study on the trajectory of CFCs throughout the twentieth century, from ideal technological solution to protagonist of an unprecedented scale chemical risk, was developed. In addition, the study includes an analysis of letters from readers, editorials and book reviews published in five journals: Chemical & Engineering News, Journal of Chemical Education, Environmental Science and Technology, Nature and Science, in the period between 1975 and 1991, and also an analysis of Environmental Chemistry textbooks published between 1970 and 1995 - a period marked by intense debate about the possibility of destruction of the stratospheric ozone layer. The choice of these journals and books sought to include different sections of the chemistry community, in order to get a representative sample of different ways of thinking within the broad professional spectrum of chemistry. Douglas\' and Wildavsky\'s Cultural Theory was selected to analyse this sample. The theory describes four worldviews that seems rather appropriate to analyze risk perceptions, attitudes and arguments involved in the discussions of the time. Results point to changes in chemists\' risk perceptions, which brought them closer to the Precautionary Principle as a guide to decision making in a period marked by the development of Environmental Chemistry.
10

Comportement du deutérium dans les matériaux d’intérêt pour la fusion thermonucléaire / Deuterium behavior in first-wall materials for nuclear fusion

Bernard, Elodie 31 October 2012 (has links)
Dans la conception des futurs réacteurs de fusion, l’impact des interactions plasma – paroi pèse grandement sur le choix des matériaux à utiliser en première interface. L’utilisation du tritium en tant que combustible impose de plus des limites de sécurité quant à la quantité totale contenue dans le réacteur. L’analyse d’échantillons de parois de Tokamaks a montré une pénétration et une rétention du deutérium (utilisé à la place du tritium) au sein des matériaux carbonés; cette rétention est problématique car contrairement à la rétention dans les couches co-déposées, on ne peut espérer l’éliminer facilement. De part l’accès difficile aux échantillons réels, l’étude de ce phénomène se limite souvent à des analyses post-mortem.Afin d’accéder à la dynamique du phénomène et de s’affranchir de potentielles redistributions des éléments lors du stockage, un dispositif couplant micro analyse nucléaire (µNRA) et implantation basse énergie simultanée, visant à reproduire l’interaction entre le deutérium et les matériaux de la première paroi, a été mis en place. L’analyse µNRA permet de caractériser les profils de répartition en trois dimensions du deutérium en temps réel, à des échelles micrométriques. Des tests ont permis de confirmer le caractère non-perturbateur du faisceau d’analyse.On observe sur l’ensemble des données obtenues que la surface de l’échantillon (0-1 µm) présente une teneur en deutérium élevée et quasi constante ; la répartition du deutérium y est uniforme. A contrario, le deutérium piégé en profondeur (1-11 µm) se concentre dans des sites préférentiels liés à la microstructure du matériau. L’inventaire deutérium en profondeur semble augmenter avec la fluence incidente, malgré une grande dispersion des données attribuée à la variation de structure des zones étudiées. La saturation surfacique comme la migration en profondeur sont instantanées ; le stockage sous vide entraine une légère désorption du deutérium.Les observations faites par µNRA ont été croisées avec celles obtenues via d’autres techniques expérimentales. La µtomographie X a permis d’identifier clairement les porosités comme sites de localisation préférentielle du deutérium en profondeur. La micro-spectrométrie Raman a révélé la formation d’une couche amorphe fine (~30 nm) et saturée en deutérium à la surface du CFC suite à l’exposition au faisceau de deutérium. Enfin, la caractérisation expérimentale de la migration du deutérium dans les CFC obtenue est confrontée aux modèles existants, et un modèle simplifié original est proposé. Considérant que le dépôt en profondeur se produit par le biais de l’implantation et de la diffusion coulombienne du deutérium à la surface des porosités, il permet de reproduire qualitativement les profils de migration observés. / Plasma-wall interactions play an important part while choosing materials for the first wall in future fusion reactors. Moreover, the use of tritium as a fuel will impose safety limits regarding the total amount present in the tokamak. Previous analyses of first-wall samples exposed to fusion plasma highlighted an in-bulk migration of deuterium (used as an analog to tritium) in carbon materials. Despite its limited value, this retention is problematic: contrary to co-deposited layers, it seems very unlikely to recover easily the deuterium retained in such a way. Because of the difficult access to in situ samples, most published studies on the subject were carried out using post-mortem sample analysis.In order to access to the dynamic of the phenomenon and come apart potential element redistribution during storage, we set up a bench intended for simultaneous low energy ion implantation, reproducing the deuterium interaction with first-wall materials, and high energy microbeam analysis. Nuclear reaction analysis performed at the micrometric scale (µNRA) allows characterizing deuterium repartition profiles in situ. This analysis technique was checked to be non-perturbative.We observed from the experimental data set that the material surface (depth 0-1 µm) displays a high and nearly constant deuterium content, with a uniform distribution. On the contrary, in-bulk deuterium (1-11 µm) localizes in preferential trapping sites related to the material microstructure. In-bulk deuterium inventory seems to increase with the incident fluence, in spite of the wide data scattering attributed to the structure variation of studied regions. Deuterium saturation at the surface as well as in-depth migration is instantaneous; in-vacuum storage leads only to a small deuterium global desorption.Observations made via µNRA were combined with results from other characterization techniques. X-ray µtomography allowed identifying porosities as the preferential trapping sites for in-depth deuterium retention. Raman µspectrometry disclosed the formation of an amorphous layer at the surface, very thin (~30 nm) and deuterium saturated, following deuterium irradiation.At last, we confronted the experimental characterization obtained with existing models for deuterium behaviour in carbon materials and proposed a simple and original one. Considering that in-depth retention is due to deuterium implantation and Coulombian diffusion at the open porosity surfaces, it allows reproducing qualitatively the observed experimental profiles.

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