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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.
181

Catalytic Organic Molecular Transformations Involving Iridium-Mediated Hydride Transfer as a Key Step: An Application for Dehydrogenation and Borrowing Hydrogen Reaction / イリジウムによるヒドリド移動を鍵とする触媒的有機分子変換反応:脱水素化反応と水素借用反応への応用

Jeong, Jaeyoung 23 March 2022 (has links)
京都大学 / 新制・課程博士 / 博士(人間・環境学) / 甲第23991号 / 人博第1043号 / 新制||人||245(附属図書館) / 2022||人博||1043(吉田南総合図書館) / 京都大学大学院人間・環境学研究科相関環境学専攻 / (主査)教授 藤田 健一, 教授 小松 直樹, 教授 津江 広人, 教授 大江 洋平 / 学位規則第4条第1項該当 / Doctor of Human and Environmental Studies / Kyoto University / DFAM
182

Synthèse de N-hydroxyphtalimides hautement fonctionnalisés via la cycloaddition [2+2+2] de a,w-diynes catalysée par des complexes d'iridium et de rhodium. Evaluation de leur activité en tant que catalyseurs d'oxydation aérobie.

Alvarez-Galan, Leonardo 28 September 2009 (has links) (PDF)
Une nouvelle stratégie de synthèse pour la préparation de N-hydroxyphtalimides par le biais de la cycloaddition [2+2+2] entre le maléimide et des α,ω-diynes catalysée par le système [IrCl(COD)]2/DPPE ou [RhCl(COD)]2/DPPE a été développée. Cette nouvelle méthodologie de synthèse nous a permis de préparer 17 N-hydroxyphtalimides originaux en seulement quatre étapes et avec des rendements compris entre 47 et 85%. Nous avons aussi utilisé cette approche dans la préparation de 5 nouveaux N-hydroxyphtalimides possédant deux axes d'atropoisomèrie et 2 phtalimides originaux énantio- et atropoisomèriquement purs avec des rendements compris entre 15 et 44%. L'activité de ces N-hydroxyphtalimides en tant que catalyseurs d'oxydation aérobie a été évaluée et nous avons obtenu dans certains cas, des activités similaires à celle du NHPI, l'indane étant transformé en indanone avec 57% de rendement à un taux de conversion de 84% dans nos conditions de réactions.
183

Excitation transfer between conjugated polyelectrolytes and triplet emitter confined in protein nanowires

Thinprakong, Chorpure January 2010 (has links)
<p>Phosphorescent metal complexes can be incorporated into amyloid-like fibrils, and these fibrils can be decorated with conjugated polyelectrolytes (CPEs). In this study, <em>fac</em>-tris[2-phenylpyridinato-<em>C</em><sup>2</sup>,N]irdium(III) complexes [Ir(piq)<sub>3</sub>] were used as the phosphorescence emitter and Sodium-poly(3-thiophene acetic acid) (PTAA-Na) compounds were used as CPEs. Herein we study the energy transfer processes between the iridium complexes and the CPEs. To investigate these mechanisms, the analysis of the emission quenching and time-resolved measurements were done. Our measurements show that energy can be transfered from singlet state of PTAA to the singlet state of Ir(piq)<sub>3</sub>. Moreover, incorporation of iridium into amyloid fibrils decreases the importance of energy transfer by the Dexter mechanism. Finally we propose a geometry of interaction to explain the obtained results.</p>
184

Excitation transfer between conjugated polyelectrolytes and triplet emitter confined in protein nanowires

Thinprakong, Chorpure January 2010 (has links)
Phosphorescent metal complexes can be incorporated into amyloid-like fibrils, and these fibrils can be decorated with conjugated polyelectrolytes (CPEs). In this study, fac-tris[2-phenylpyridinato-C2,N]irdium(III) complexes [Ir(piq)3] were used as the phosphorescence emitter and Sodium-poly(3-thiophene acetic acid) (PTAA-Na) compounds were used as CPEs. Herein we study the energy transfer processes between the iridium complexes and the CPEs. To investigate these mechanisms, the analysis of the emission quenching and time-resolved measurements were done. Our measurements show that energy can be transfered from singlet state of PTAA to the singlet state of Ir(piq)3. Moreover, incorporation of iridium into amyloid fibrils decreases the importance of energy transfer by the Dexter mechanism. Finally we propose a geometry of interaction to explain the obtained results.
185

Electrochromic Properties of Iridium Oxide Based Thin Films

Backholm, Jonas January 2008 (has links)
Electrochromic iridium oxide (IrOx) and iridium-tantalum oxide (IrTaOx) thin films were prepared by reactive magnetron sputtering. Composition, density, and structure were determined using Rutherford backscattering spectroscopy, X-ray photoelectron spectroscopy, X-ray diffraction, scanning electron microscopy, transmission electron microscopy, and electron energy loss spectroscopy. The electronic density of states (DOS) and the solid phase chemical diffusion coefficient (D) were determined for hydrogen in IrOx and IrTaOx by potentiostatic intermittent titration technique (PITT), and electrochemical impedance spectroscopy (EIS). The complex refractive indices were determined for colored and bleached IrOx and IrTaOx by inverting transmission and reflectance, measured using spectrophotometry in the 300-2500 nm wavelength range. A very porous structure, with a stoichiometry of IrO2.2, was found for IrOx. It contained ~4 nm sized grains. The IrTaOx had a denser structure built up by ~4 nm sized grains. The composition of IrTaOx was found to vary on a nanometer scale, with an average composition of IrTa1.4O5.6. It was found that DOS can be measured using PITT and EIS in the presence of spontaneous side reactions, even for systems influenced by non-negligible charge transfer kinetics and Ohmic drops. It was found that the measured DOS is 30-50% of the theoretically calculated DOS and that D is in the 10-10 – 10-11 cm2/s range for both materials. The hydrogen diffusion mechanism was described by an anomalous diffusion model, possibly indicating percolation or diffusion paths described by a fractal network. The refractive indices were found to be ~1.3 and ~2 for IrOx and IrTaOx, respectively, and independent of coloration state, whereas the extinction coefficients were found to modulate by ~30% for IrOx and ~50% for IrTaOx, making IrTaOx more favorable for electrochromic applications. A modulation peak was found at ~660 nm for both IrOx and IrTaOx associated with the removal of intraband transitions within the Ir t2g band.
186

Investigation of carrier transport in organic optoelectronic devices and iridium complex based phosphorescent light emitting devices

Jhan, Yi-Pin 13 August 2012 (has links)
In this research, the contents are divided into two sections. In the first section, we investigated carrier transport behavior of organic optoelectronic devices by using space charge limited current(SCLC) method. Firstly, we fabricated a hole-only device (ITO/Spiro-MeOTAD/Al) for Sprio-MeOTAD and the current density¡V voltage(J-V) characteristics of the device was measured. The J-V characteristics of the device do not match with SCLCs very well at high voltage since the number of hole injection was not enough to achieve SCLCs condition. To enhance the injection of hole carrier into the organic layer, a MoO3 buffer layer was inserted between ITO electrode and organic layer. The current density in device with MoO3 buffer layer achieved 5 times enhancement, indicating that the concentration of hole in MoO3 device is increment. Hence, we succeeded in making the J-V characteristics of the hole-only device to match with SCLCs well at high voltage, and the hole mobility of Sprio-MeOTAD estimated by SCLCs was 1.44¡Ñ10-4cm2/Vs. Li salt was also doped into Sprio-MeOTAD as an n-type dopant. We found that Li salt could form hole-traps in Sprio-MeOTAD, which reduced hole carriers in Spiro-MeOTAD. The current density of the device was decreased, and the device could not achieve SCLCs condition at high voltage. In the second section, we use two novel iridium(Ir) complexes to fabricate blue-green emitting devices by solution process. First, we obtained optimum concentration of phosphorescent emitters by controlling of the dopants concentration. Then, we adjusted the thickness of the electron injection layer, hole injection layer, and emission layer to design more suitable device structure. Finally, we succeeded in fabricating blue-green light emitting devices. The maxima luminescence was 37.7cd/m2 and maxima current efficiency was 1.68 cd/A in the Ir complex based devices.
187

Methods for calculating rates of transitions with application to catalysis and crystal growth /

Henkelman, Graeme, January 2001 (has links)
Thesis (Ph. D.)--University of Washington, 2001. / Vita. Includes bibliographical references (p. 129-136).
188

Aminophosphine-oxazolines

Blanc, Catherine Agbossou-Niedercorn, Francine January 2005 (has links)
Reproduction de : Thèse de doctorat : Chimie organique et macromoléculaire : Lille 1 : 2004. / Titre provenant de la page de titre du document numérisé.
189

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.
190

Iridium-catalyzed C-C bond formation : development of crotylation and methallylation reactions through transfer hydrogenation

Townsend, Ian A. 19 July 2012 (has links)
Under the conditions of transfer hydrogenation utilizing chromatographically purified ortho-cyclometallated iridium C,O-benzoate precatalysts, enantioselective carbonyl crotylation and methallylation can be performed in the absence of stoichiometric metallic reagents and stoichiometric chiral modifiers. In the case of carbonyl crotylation, use of a preformed precatalyst rather than an in situ generated catalyst results in lower reaction temperatures, providing generally higher diastereoselectivity and yields. By utilizing a more reactive leaving group in chloride over acetate on our methallyl donor, the inherently shorter lifetime of the olefin π-complex is compensated for, giving our group’s first report of reactivity utilizing 1,1-disubstituted allyl donors. / text

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