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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.
191

Synthesis and redox behaviour of some tetramine complexes of ruthenium III and iridium III /

Tang, Tin-wu. January 1982 (has links)
Thesis--Ph. D., University of Hong Kong, 1982.
192

Basel III, banker och kreditgivning : En studie av Basel III:s påverkan på bankers kreditgivning till nystartade företag

Ekmark, Victor, Hirschfeldt, Didrik January 2015 (has links)
I Sverige klassificeras cirka 99,4 % av alla företag som mindre företag och under 2014 registrerades cirka 70 000 nya företag. Gemensamt är att nystartade och mindre företag som växer och utvecklas bidrar till nationell tillväxt i länderna de är verksamma inom. För att företagen ska kunna växa krävs finansiering och banker har traditionellt tillgodosett detta behov. Regelverket Basel III är därför väldiskuterat eftersom flera studier visar att det kan påverka bankers kreditgivning. Forskning visar bland annat att Basel III leder till minskad utlåning och ökade utlåningsräntor. Det visar också att nystartade företag kan missgynnas mer än andra bolag på grund av de interna riskklassificeringssystem som tillåts inom regelverket. Interna riskklassificeringssystem kan nämligen, på grund av olika variabler och parametrar, göra att nystartade företag betraktas som mer riskfyllda. Andra studier som gjorts i ämnet visar att Basel III inte påverkar varken banker, kreditgivning eller utlåningsräntor. Eftersom tidigare forskning och litteratur visar olika resultat syftar denna studie till att undersöka, beskriva och öka förståelsen för hur Basel III påverkat kreditgivningen till nystartade företag i Sverige. För att få empiriskt underlag till studien har tio intervjuer gjorts med elva respondenter från sju olika banker. Intervjuer har gjorts med anställda på större och mindre banker på central och lokal nivå. Resultatet i studien visar att alla banker höjt utlåningsräntorna till nystartade företag. Bankerna uppger att det framför allt beror på förändrad risksyn och riskbedömning till följd av Basel III. Basel III har lett till att företagskunder prissätts mer efter bedömd kreditrisk och detta har gjort att nystartade företag generellt fått en högre ränta. Resultatet visar också att interna system och modeller blivit viktigare inom bankerna och att alternativa finansieringslösningar börjat växa fram på marknaden. Samtidigt är kreditbedömningsprocessen och låneutbudet oförändrat sedan Basel III:s introduktion. Studiens resultat bidrar med praktiska implikationer till nystartade företag, banker, entreprenörer och samhället. Den bidrar också teoretiskt till forskningen i form av underlag till diskussionen om utlåningsräntor och låneutbud. / In Sweden approximately 99.4% of all companies are classified as small companies and in 2014 around 70,000 new companies were registered. The common denominator is that start-ups and small businesses that grow and evolve contribute to national growth in the countries they operate in. In order to enable businesses to grow they require finance and traditionally banks have met this need. Basel III is therefore a well-argued subject since several studies show that it can affect banks' lending. Research shows that Basel III will lead to reduced lending and increased lending rates. It also shows that start-ups may be more disadvantaged than other companies because of the internal ratings-based (IRB) approach allowed within the regulation. The IRB approach can namely, because of different variables and parameters, consider start-ups more risky than other companies. Other studies however, show that Basel III has no, or very little, impact on lending and interest rates. Since previous research and literature shows different results this study aims to examine, describe and increase the understanding of how Basel III impact lending to start-ups in Sweden. Ten interviews with eleven respondents from seven different banks have been conducted. The interviews were conducted with employees of large and small banks working on central and local level. The results of the study show that all banks have raised lending rates to start-ups. The banks say that it is mainly due to changed risk profile and risk assessment as a result of Basel III. Basel III has led to corporates, retails and start-ups being priced on estimated credit risk and this has led to start-ups being considered as riskier. Thus, banks have raised lending rates to start-ups. The result also shows that internal systems and models have become more important in banks and that alternative financing has begun to emerge on the market. Meanwhile, the credit assessment process and the loan supply are unaffected since Basel III's introduction. The study's results contribute with practical implications for start-ups, banks, entrepreneurs and the community. It also contributes to theoretical research regarding the lending rates and loan supply discussion.
193

Synthesis, Structure and Reactivity of Bismuth(III) and Aluminum(III) Complexes Supported by Nitrogen Donor Ligands

Nekoueishahraki, Bijan 21 January 2010 (has links)
No description available.
194

Utvecklingen av den svenska företagsobligationsmarknaden : En institutionell analys av förändrade förutsättningar och dess påverkan på transaktionskostnader / The Development of the Swedish Corporate Bond Market : An Institutional Analysis of changing Market Conditions and their Impact on Transaction Costs

Petersson, Daniel, Vikdahl, Kristin, Nilemar, Jesper January 2013 (has links)
Bakgrund: De svenska företagens lånebaserade finansiering har historiskt sett mestadels utgjorts av banklån framför företagsobligationer. Efter finanskrisens start 2008, och fram till och med fjärde kvartalet år 2012, har den svenska företagsobligationsmarknaden vuxit med drygt 60 procent. I media framställs en bild där regelverket Basel III har gjort och kommer göra företagsobligationsmarknaden till en viktigare finansieringskälla för svenska företag. En studie om företagsobligationsmarknaden efterfrågas av Svenskt Näringsliv. Syfte: Syftet med studien är att kartlägga och utifrån institutionell teori analysera hur de ekonomiska förutsättningarna för den svenska företagsobligationsmarknaden har förändrats sedan år 2008. Genomförande: För att uppnå studiens syfte har ett kvalitativt tillvägagångssätt tillämpats. Empirin har samlats in genom semistrukturerade intervjuer med aktörer på företagsobligationsmarknaden. En intervjuguide utformades med grund i institutionell ekonomisk teori, med fokus på transaktionskostnader. Samma teoretiska referensram har sedan använts för att analysera den insamlade empirin. Slutsats: Tiden innan år 2008 kännetecknades av att företagen valde banklån. Detta för att bankerna kunde hantera banklån till låga transaktionskostnader. Institutionella förändringar sedan år 2008 har lett till att transaktionskostnaderna sänkts på företagsobligationsmarknaden. Företagsobligationer har således blivit ett bättre alternativ för många företag, även fast små företag fortfarande är utestängda från marknaden. / Background: Swedish corporates’ debt financing have historically mostly consisted of bank loans instead of corporate bonds. Since the beginning of the financial crisis of 2008, leading up to the fourth quarter of 2012, the Swedish corporate bond market has grown by over 60 per cent. Media coverage of the market presents a picture where the corporate bond market has become an important source of financing as a result of the legal framework Basel III. A study of the corporate bond market has been requested by the Confederation of Swedish Enterprise. Aim: The purpose of the study is to identify and, by the use of institutional theory, analyse how the market conditions in the Swedish corporate bond market have changed since the year of 2008. Completion: To achieve the purpose of the study a qualitative research method has been applied. Empirical data have been collected through semi-structured interviews with stakeholders in the Swedish corporate bond market. An interview guide was designed from an institutional theory perspective with a focus on transaction costs. The same theoretical framework has been used to analyze the empirical data. Conclusion: Before the year of 2008, debt financing was characterised by bank loans. This was the result of the banks’ ability to keep transaction costs low. Since the year of 2008, institutional changes have decreased transaction costs on the Swedish corporate bond market. Corporate bonds have become a more attractive alternative for many companies, even though small companies are still excluded from the market.
195

Gravitational lensing as a probe of the first stars and galaxies

Rydberg, Claes-Erik January 2015 (has links)
This thesis investigates the potential for detection and identification of primordial stars, galaxies, and supernovae at high redshift. Simulations indicate that the first Population III stars should appear in minihalos of mass M = 105-106 Msol at z ≈ 10-30. To assess the detectability of these objects, theoretical models of these stars and their surrounding HII regions are used. We assess the plausibility of detection with the upcoming James Webb Space Telescope (JWST), using the gravitational lensing provided by the galaxy cluster MACSJ0717.5+3745. The conclusion is that the detection of these objects is highly improbable but not impossible. To investigate the prospects of detecting and identifying the first galaxies, the spectral synthesis code Yggdrasil is introduced. According to this code, JWST may be able to detect Population III galaxies with stellar masses as low as 105 Msol at z ≈ 10 in unlensed fields. We find that, over limited redshift intervals, it could be possible to use Hubble Space Telescope (HST) and/or JWST broadband color criteria to single out Population III galaxy candidates. The prospects of detecting gravitationally lensed Population III galaxies with JWST and HST is investigated. A lower limit to detect ≈1 Population III galaxy of ε ≈ 10-2 (HST/CLASH) and ε ≈ 10-3 (JWST using MACS J0717.5+3745 as lens) is derived, where ε is the baryon fraction converted to Population III stars in a host halo. By fitting HST/CLASH data to Yggdrasil and comparison grids, two Population III galaxy candidates are discovered. These two candidates are the first Population III galaxy candidates discovered at z &gt; 6.5. A highly-magnified and doubly lensed extremely high-redshift (z ≈ 7.8) object is also identified. Finally the prospects of detecting core-collapse (CC) supernovae (SN) from the first galaxies at z ≈ 5-12 are investigated. The prediction is that no primordial SN is detectable, but 2-3 CC SN should be discovered by the HST/CLASH. / <p>At the time of the doctoral defense, the following papers were unpublished and had a status as follows: Paper 5: Submitted. Paper 6: Submitted. Paper 7: Manuscript.</p>
196

Ab-initio-Cluster-Rechnungen und Monte-Carlo-Simulationen zur Adsorption von CO auf der Cr203(0001)-Oberfläche

Pykavy, Mikhail. January 1999 (has links) (PDF)
Bochum, Universiẗat, Diss., 1999.
197

Modélisation compacte de transistors MOSFETs à canal III-V et films minces pour applications CMOS avancées / Compact modeling of MOSFETs transistors with III-V channels and thin film for advanced CMOS applications

Hiblot, Gaspard 23 October 2015 (has links)
Les MOSFET III-V sont considérés comme des candidats potentiels pour les futures générations d'applications à base de logique CMOS, grâce à leurs remarquables propriétés de transport.D'un autre côté, ils souffrent de désavantages physiques (tels que les courants tunnels ou leur faible densité d'états), et de difficultés technologiques (en particulier les états d'interface), qui peuvent détériorer leur performance.Dans cette thèse, un modèle physique et compact du MOSFET III-V est établi. Il inclut une description des effets canaux courts, de la charge d'inversion (considérant aussi les effets de structure de bandes dans les canaux fins), les caractéristiques de transport, les courants tunnels, et les composants externes tels que les résistances d'accès et les capacités parasites.En utilisant ce modèle, la performance des MOSFET III-V est évaluée par rapport à celle du Si, et une feuille de route incluant ces dispositifs est présentée.Il est démontré que les canaux à matériaux III-V pourraient présenter une meilleure performance que le Si, pourvu que le problème des pièges d'interface soit résolu. Si tel est le cas, ils pourraient être introduits au noeud "7nm".La densité de pièges, à partir de laquelle la performance des MOSFET III-V devient pire que celle du Si, dépend de l'architecture considérée.Enfin, les canaux très fins nécessaires pour atteindre une bonne performance avec les matériaux III-V risquent de poser des problèmes de variabilité, qui pourraient avec des répercussions négatives au niveau de la conception du circuit. / III-V MOSFETs are considered as a potential candidate for next generation CMOS logic applications thanks to their remarkable transport properties.On the other hand, they suffer from several physical drawbacks (such as tunneling currents or low density-of-states) and technological difficulties (in particular interface traps), which may deteriorate their performance.In this thesis, a physical compact model of the III-V MOSFET is established. It includes a description of short-channel effects, inversion charge (also considering bandstructure effects in thin channels), transport characteristics, tunneling currents, and external components such as access resistances and fringe capacitances. Using this model, the performance of III-V MOSFETs is benchmarked against Si, and a possible roadmap including these devices is presented. It has been found that the III-V channels may feature a significant performance advantage over Si, provided that the interface traps issue be solved. In that case, they may be introduced at the "7nm" node. The critical trap density, above which the performance of III-V MOSFETs degrades below Si, depends on the architecture considered. Finally, the very thin channels required to achieve a good performance with III-V materials may raise variability issues that could reverberate negatively at the circuit design level.
198

Development and understanding of III-N layers for the improvement of high power transistors / Développement et compréhension des couches III-N pour l'amélioration des transistors de haute puissance

Bouveyron, Romain 31 October 2017 (has links)
Cette thèse est principalement axée sur le développement des matériaux III-N pour les transistors de puissance HEMTs, ainsi que les multipuits quantiques et les applications optroniques qui en découlent dans une moindre mesure. Suite à un rappel des propriétés des nitrures, des différentes applications possibles, du principe de la MOCVD et des différentes caractérisations retenues pour ce travail, nous avons traité dans un premier temps la croissance de GaN à basse température, c'est-à-dire en dessous de 1050degres C. La fabrication de multipuits impliquant l’alternance des couches de GaN et d'InAlN ou InGaAlN nous contraint de travailler à ces températures ce qui génère l’apparition d’un défaut en surface du GaN que l’on nomme V-defect. Une étude expérimentale poussée nous a permis de comprendre comment apparaissent et évoluent ces défauts selon les paramètres de croissance. Un modèle basé sur les énergies de surface à pu être élaboré et explique l’évolution de ces défauts. Ensuite nous avons défini l'influence de nombreux paramètre de croissance par MOCVD et tiré, des multiples tendances mises en relief, des modèles et explications justifiant telle ou telle propriété physique et chimique du matériau. En aval, ce sont des caractérisations électriques et principalement des mesures de résistivités qui ont été traitées afin de comparer la performance de nos échantillons à base d'indium à ceux de type AlGaN/GaN. Le problème de la pollution au gallium dans les réacteurs MOCVD verticaux a été mis en évidence et nous avons proposé différentes solutions pour la limiter, voire l’annihiler. Pour terminer ce sont des couches de protection à base de SiN et GaN que nous avons tenté de développer afin de protéger nos alliages à base d’indium pour la suite des étapes technologiques nécessaires à la fabrication d’un composant par exemple. / This thesis is mainly focused on the development of III-N materials for HEMTs power transistors, as well as quantum wells and optronics applications that result to a lesser extent. Following a reminder of the properties of nitrides, the different possible applications, the principle of the MOCVD and the different characterizations used for this work, we first treated the growth of GaN at low temperature, that is to say below 1050degres C. The manufacture of multiple quantum wells involving the alternation of GaN and InAlN or InGaAlN layers forces us to work at these temperatures, which generates the appearance of a defect in surface of the GaN which is called V-defect. An advanced experimental study allowed us to understand how these defects appear and evolve according to the growth parameters. A model based on surface energies could be developed and explains the evolution of these defects. Then we defined the influence of many MOCVD growth parameters by MOCVD and derived, from the multiple trends highlighted, the models and explanations justifying this or that physical and chemical property of the material. Downstream, these are electrical characterizations and mainly resistivity measurements that have been processed to compare the performance of our indium-based samples to those of AlGaN/GaN type. The problem of gallium pollution in vertical MOCVD reactors has been highlighted and we have proposed different solutions to limit or even annihilate it. Finally, we have tried to develop protective layers based on SiN and GaN in order to protect our indium-based alloys for the next technological steps required to manufacture a component, for example.
199

Possibilities of Royal Power in the Late Carolingian Age : Charles III "The Simple" / Champ d'action et marges de manoeuvre du pouvoir royal au temps des derniers Carolingiens : L'exemple de Charles III "Le Simple" (893/898 à 923)

Lösslein, Horst 08 February 2017 (has links)
La thèse est dédiée à analyser les possibilités du pouvoir royal à l’époque des derniers Carolingiens en étudiant le règne de Charles III le Simple (893/898-923) et en le comparant avec ceux de ses prédécesseurs depuis la mort de son grand-père Charles II le Chauve en 877, c’est ce que permet aussi l’identification des développements à moyen terme des structures politiques du monde Franc. Le pouvoir royal se devait de naître des interactions entre le roi et les nobles autour de lui. Selon les interprétations de la recherche récente, ces derniers sont considérés comme des partenaires du premier, qui participent dans le processus de sa prise de décision et qui fonctionnent comme des exécuteurs des décisions prises en consensus, transmettant ainsi le pouvoir royal dans les différentes parties du royaume. La question des marges de manœuvre du pouvoir royal est donc une question des relations entre le roi et les nobles qui l’entourent. En conséquence, l’étude de ces relations constitue l’axe central de cette étude. Les réseaux des nobles en contact avec les rois sont identifiés et l’influence des nobles individuels ainsi que des groupes est déterminée en analysant les diplômes royaux et en les mettant dans le contexte des sources narratives. Pendant les règnes de Louis II le Bègue (877-897) et ses fils Louis III (879-882) et Carloman II (882-884), jusqu'à celui de Charles III le Gros (884-888), l’existence d’un et plus tard de deux groupes qui dominaient la politique royale est révélée. Cette image change sous le dernier, qui promouvait certains nobles qui entretenaient des liens avec ces anciens groupes. Le manque de cohérence de cette nouvelle élite devient évident après la mort de Charles le Gros, quand des groupes rivaux soutinrent différents candidats pour le trône vacant. Cette fragmentation de l’élite du royaume continua pendant le règne d’Eudes (888-898) jusqu’aux premières années de Charles le Simple. Ce n’est qu’après la mort de certaines figures clés que l’intégration des nobles qui s’opposaient au nouvel ordre dans le cercle autour du nouveau roi devint possible. Pendant les prochaines décennies du règne de Charles, ce cercle fut modifié encore plusieurs fois, par l’addition d’un grand nombre de nobles après l’acquisition de la Lotharingie ainsi que par l’ascendance d’un nouveau groupe favorisé par Charles vers les dernières années 910s. Cette analyse constitue la base pour une évaluation des activités des rois concernant leurs pairs et les Vikings. Une collaboration étroite entre les rois est mise en lumière pour avoir d’une part stabilisé les relations entre ces rois et leurs nobles, et d’autre part, pour avoir limité aussi au même moment les marges de manœuvres des rois concernant leurs propres intérêts dans les royaumes voisins. Concernant les mesures prises contre les Vikings, des stratégies purement militaires pour sécuriser le royaume s’avèrent avoir été inefficaces. Ce n'était seulement que par des accords diplomatiques avec les Vikings, négociés et mis en œuvre avec le soutien des grands, que des succès sur le long terme pouvaient être obtenus. Quand pour la majeure partie de son règne Charles le Simple profitait du soutien des nobles, sa fin arriva quand même par leur rébellion en 922. Cette contradiction est résolue par l’introduction du concept sociologique de la confiance. Son importance dans les relations entre les rois et les nobles est déterminée par l’analyse de différentes situations de conflits. Il semble que la détérioration des liens entre Charles et les grands autour de lui était causée par la perception de certaines actions royales comme des violations des normes par les nobles ainsi que sa mauvaise grâce à employer une langue appropriée pour répondre à cette crise de confiance. / The thesis aims to determine the possibilities of royal power in the late Carolingian age, analysing the reign of Charles III the Simple (893/898-923). His predecessors’ reigns up to the death of his grandfather Charles II the Bald (843-877) serve as basis for comparison, thus also allowing to identify mid-term developments in the political structures shaping the Frankish world toward the turn from the 9th to the 10th century. Royal power is understood to have derived from the interaction of the ruler with the nobles around him. Following the reading of modern scholarship, the latter are considered as partners of the former, participating in the royal decision-making process and at the same time acting as executors of these decisions, thus transmitting the royal power into the various parts of the realm. Hence, the question for the royal room for manoeuvre is a question of the relations between the ruler and the nobles around him. Accordingly, the analysis of these relations forms the core part of the study. Based on the royal diplomas, interpreted in the context of the narrative evidence, the noble networks in contact with the rulers are revealed and their influence examined. Thus, over the course of the reigns of Louis II the Stammerer (877-879) and his sons Louis III (879-882) and Carloman II (879-884) up until the rule of Charles III the Fat (884-888), the existence of first one, then two groups of nobles significantly influencing royal politics become visible. This image changes only under the latter, when individual nobles originating in the immediate vicinity of the older groups were promoted. The missing inner coherence of this new elite is revealed after the death of Charles the Fat, when rivalling parties formed, which supported different candidates for the vacant throne. This fragmentation of the leading nobility continued throughout Odo’s reign (888-898) until the first years of Charles the Simple’s rule. Only then, after the death of political key figures, the full integration of those nobles opposing the new king into the circle around him became possible. Over the course of the next decades this circle underwent a number of further modifications, most of all by the integration of numerous nobles after the addition of Lotharingia to Charles’ rule as well as the ascent of a new group of nobles promoted by the king in the late 910s. These analyses constitute the basis for an evaluation of the rulers’ activities in regard to their peers as well as the Vikings. A close cooperation between the rulers is revealed to have had a stabilizing effect on the relations between the rulers and the nobles. At the same time, however, these alliances also limited their room for manoeuvre when it came to pursuing their interests against their partners. Concerning the politics pursued against the Vikings, purely military measures to secure the realm remained rather ineffective. Longer lasting success could only be obtained by diplomatic agreements with the Northmen, negotiated and implemented with the support of the leading nobles of the realm. While for the most part of his reign Charles enjoyed the support of the leading nobles, his rule, nevertheless, remains under the shadow of their rebellion against him in 922. Outlining the importance of trust by analysing different conflict situations, this contrast is resolved by arguing that the deterioration of the relations between Charles and the nobles was caused by repeated actions of the king, which were perceived as violations of the existing norms and a failure to adjust his symbolic language to respond to this crisis.
200

Detekce prionových proteinů a jejich interakce s kovy a metalothioneinem

Cardová, Alžběta January 2014 (has links)
Prion diseases are formed by a conformational change of prion-like protein (PrPC) with alfa-helix structure to the pathological isoform - prion (PrPSc) which acquires beta-sheet structure. PrPC physiological properties in the brain are insufficiently described but there is an assumption of its affinity to metal ions. Another protein with metal-binding ability is metallothionein (MT). Brain specific isoform of MT is called MT-III and it is assumed to participate in maintenance of metal ions concentration in the brain. Aim of this study was to prepare recombinant human PrPC in E. coli. Furthermore, this protein was used to detect interactions between metal ions (Cu, Zn), MT and PrPC by differential pulse voltammetry method. The final part was devoted to the MT-III determination in different genotypes of prion-infected and non-infectious mouse brain tissues.

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