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1
Stack, Christianna Otey Carol A. « The role of palladin in pancreatic cancer ». Chapel Hill, N.C. : University of North Carolina at Chapel Hill, 2008. http://dc.lib.unc.edu/u?/etd,2072.
Texte intégralRésumé :
Thesis (M.S.)--University of North Carolina at Chapel Hill, 2008.Title from electronic title page (viewed Feb. 17, 2009). "... in partial fulfillment of the requirements for the degree of Master of Science in the Department of Cell and Molecular Physiology." Discipline: Cell and Molecular Physiology; Department/School: Medicine.
2
Ludwig, Tim Alexander [Verfasser]. « Der Zebrafisch als Modellorganismus für den Knockdown von Palladin / Tim Alexander Ludwig ». Greifswald : Universitätsbibliothek Greifswald, 2014. http://d-nb.info/1059782014/34.
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3
Kim, Pil-Sang [Verfasser]. « Bedeutung von Palladin für die trainingsinduzierte Anpassung der Skelettmuskulatur / Pil-Sang Kim ». Köln : Deutsche Sporthochschule Köln, 2012. http://d-nb.info/1070867489/34.
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4
Arneman, Daniel Kenneth Anton Eva S. « The role of palladin in actin organization implications for the glial scar / ». Chapel Hill, N.C. : University of North Carolina at Chapel Hill, 2007. http://dc.lib.unc.edu/u?/etd,1612.
Texte intégralRésumé :
Thesis (Ph. D.)--University of North Carolina at Chapel Hill, 2008.Title from electronic title page (viewed Sep. 16, 2008). "... in partial fulfillment of the requirements for the degree of Doctor of Philosophy in the Department of Cell and Molecular Physiology." Discipline: Cell and Molecular Physiology; Department/School: Medicine.
5
Brungardt, Joseph G. « The phosphorylation of palladin and the effect on its interaction with actin binding, bundling, and polymerization ». Diss., Wichita State University, 2013. http://hdl.handle.net/10057/6421.
Texte intégralRésumé :
Metastatic cell motility, namely breast cancer, has been shown to be regulated in part by the protein palladin. Palladin is a recently described actin binding and bundling protein whose expression level is related to metastatic cancer cell motility. Palladin plays a role in the regulation of actin, a highly abundant protein within a cell, which acts as a cell’s skeleton. Actin is also the structural basis of invasive cellular structures known as invadopodia, which cross the extracellular matrix and allow cells to invade surrounding tissue structures. Palladin has been shown to regulate actin bundles within these invasive structures. Further studies have shown that Akt1, a prominent and highly studied protein kinase, phosphorylates palladin at a linker region between its immunoglobulin domains that are critical for actin bundling. Our work builds upon initial cell-based assays which show that normal cell function is altered when phosphorylation of palladin is misregulated. We utilized biochemical assays to quantify how phosphorylation of palladin affects the structure and function of actin to further understand both of their roles in cancer cell motility.Thesis (Ph.D.)--Wichita State University, College of Liberal Arts and Sciences, Dept. of Chemistry
6
MASTROTOTARO, GIUSEPPINA. « Molecular characterization of the sarcomeric Z-line proteins nebulette and palladin in the heart : roles in cardiac structure, function, and disease ». Doctoral thesis, Università degli Studi di Milano-Bicocca, 2015. http://hdl.handle.net/10281/94177.
Texte intégralRésumé :
The sarcomeres are the smallest contractile units of striated muscle. It is formed by actin (thin) and myosin (thick) filaments that slide over each other during contraction and is stabilized by titin filaments, which acts as a spring during contraction. In the Z-line at the boundary between sarcomeres, actin and titin filaments are cross-linked and the contractile apparatus is connected with the cytoskeleton and extracellular matrix. The Z-line is important for efficient force generation and maintenance of cardiac structure, and is a focal point for mechanosensing and signal transduction. Consistently, mutations in many Z-line associated proteins have been associated with cardiomyopathies, including nebulette and its interaction partner myopalladin. On the other hand, the role of palladin (PALLD), a homologue of myopalladin (MYPN) associated with nebulette, in the heart has remained unknown. The aim of the present project was to investigate the function of nebulette and palladin in the heart. Nebulette is a 109 kDa modular protein composed of nebulin repeats and a C-terminal SH3 domain. In vitro studies have suggested a role of nebulette in stabilizing the thin filament, and missense mutations in the nebulette gene have been found to be causative for dilated cardiomyopathy and endocardial fibroelastosis in human and mice. However, the role of nebulette in vivo has remained unknown. To study the functional role of nebulette in the heart in vivo, we generated and studied nebulette knockout (nebl-/-) mice. Functional analyses revealed normal cardiac function of nebl-/- mice both at basal conditions and in response to transaortic constriction (TAC). Furthermore, histological, immunofluorescence, and Western blot analyses showed no cardiac abnormalities in nebl-/- mice. On the other hand, Z-line widening was observed from 5 months of age and the presence of chronic cardiac stress was suggested by the upregulation of cardiac stress responsive genes. Thus, nebulette may play an important role for Z-line integrity, while the absence of a functional phenotype of nebl-/- mice suggests that nebulette cardiomyopathy mutations have gain-of-function effects. PALLD, MYPN, and myotilin (MYOT) make up a small protein family of immunoglobulin-containing proteins in the sarcomeric Z-line associated with α-actinin and filamentous actin. MYPN and MYOT are expressed as single isoforms in striated muscle, while PALLD is ubiquitously expressed in several isoforms. The longest 200 kDa PALLD isoform is expressed predominantly in striated muscle and is highly homologous in structure to MYPN, suggesting a similar role of the two proteins in striated muscle. However, while mutations in the MYPN gene have been associated with dilated, hypertrophic, and restrictive cardiomyopathy, the role of PALLD in the heart has remained unknown. Since PALLD knockout mice are embryonic lethal, to study the role of PALLD in heart, we generated constitutive (cPKO) and inducible (cPKOi) cardiac specific PALLD knockout mice. cPKO mice showed normal cardiac function both at basal conditions and following TAC, while inducible knockout of PALLD in adult cPKOi mice resulted in progressive cardiac dilation and systolic dysfunction, associated with fibrosis, upregulation of markers of cardiac pathological remodeling, and ERK activation. Furthermore, PALLD was found to activate serum response factor (SRF) signaling and strongly increase MRTF-A-mediated activation of SRF, likely through its direct interaction MRTF-A and role in modulating actin dynamics. The development of a dilated cardiomyopathy in cPKOi mice induced at adult stage demonstrates that PALLD is essential for normal cardiac function and suggests that PALLD gene mutations may be causative for cardiomyopathy. The absence of a cardiac phenotype of cPKO mice may be due to compensatory mechanisms.
7
Artelt, Nadine Verfasser], Karlhans [Akademischer Betreuer] Endlich, Karlhans [Gutachter] Endlich, Thomas [Gutachter] Weide et Sigrid [Gutachter] [Hoffmann. « Untersuchung des Einflusses von Palladin auf das Aktinzytoskelett von Podozyten / Nadine Artelt ; Gutachter : Karlhans Endlich, Thomas Weide, Sigrid Hoffmann ; Betreuer : Karlhans Endlich ». Greifswald : Universität Greifswald, 2020. http://d-nb.info/1207502073/34.
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8
Artelt, Nadine Verfasser], Karlhans [Akademischer Betreuer] [Endlich, Karlhans Gutachter] Endlich, Thomas [Gutachter] [Weide et Sigrid [Gutachter] Hoffmann. « Untersuchung des Einflusses von Palladin auf das Aktinzytoskelett von Podozyten / Nadine Artelt ; Gutachter : Karlhans Endlich, Thomas Weide, Sigrid Hoffmann ; Betreuer : Karlhans Endlich ». Greifswald : Universität Greifswald, 2020. http://d-nb.info/1207502073/34.
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9
Artelt, Nadine [Verfasser], Karlhans [Akademischer Betreuer] Endlich, Karlhans [Gutachter] Endlich, Thomas [Gutachter] Weide et Sigrid [Gutachter] Hoffmann. « Untersuchung des Einflusses von Palladin auf das Aktinzytoskelett von Podozyten / Nadine Artelt ; Gutachter : Karlhans Endlich, Thomas Weide, Sigrid Hoffmann ; Betreuer : Karlhans Endlich ». Greifswald : Universität Greifswald, 2020. http://d-nb.info/1207502073/34.
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10
Frizzale, Tommaso. « Palladio digitale. Studio e ricostruzione di un progetto palladiano : villa Mocenigo ». Master's thesis, Alma Mater Studiorum - Università di Bologna, 2011. http://amslaurea.unibo.it/2132/.
Texte intégralRésumé :
L’obiettivo che l’elaborato si prefigge consiste nel dar forma ad un progetto palladiano rimasto sulla carta attraverso l’utilizzo delle tecnologie informatiche.
Nello specifico si è ricostruita Villa Mocenigo in forma tridimensionale attraverso uno schizzo del progetto fatto su carta dallo stesso Palladio nel 1550. Lo schizzo della pianta, conservato al RIBA di Londra, anticiperebbe il successivo progetto finale pubblicato ne “I Quattro Libri dell’Architettura” ma rimasto comunque incompiuta.
Il linguaggio di base utilizzato per la definizione dell’ipotesi progettuale del modello 3D è stato attinto dalle regole generali di proporzionamento “alla maniera degli antichi” che lo stesso Architetto illustra nel suo trattato.
Al fine di rendere l’ipotesi ricostruttiva il più possibile in linea con il metodo di proporzionamento palladiano, come esercitazione, si è partiti dallo studio preparatorio di un altro progetto: Villa Sarego, edificata solo in parte. A partire quindi dalla ricostruzione 3D basata sui disegni dei rilievi eseguiti dal CISAAP è stata avanzata l’ipotesi di ricostruzione totale della villa, completa della parte incompiuta.
Lo studio sintetizzato in questo elaborato ha anche riguardato:
la composizione architettonica e lo studio delle regole proporzionali evolutesi nel tempo;
il processo di digitalizzazione e archiviazione delle opere palladiane e i progetti attualmente in corso;
escursus storico sulle ville romane;
le opera di Palladio, costruite e progettate.
11
Arciszewska, Barbara. « The Hanoverian court and the triumph of Palladio : the Palladian revival in Hanover and England c. 1700 / ». Warsaw : Wydawn.DiG, 2002. http://www.loc.gov/catdir/toc/fy0609/2005478972.html.
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12
Cornelio, Benedetta. « Nanoparticules de palladium comme catalyseurs : Conception, analyses et application pour la préparation de dérivés bisaryliques d'intérêt biologique ». Thesis, Reims, 2014. http://www.theses.fr/2014REIMP203.
Texte intégralRésumé :
Un grand nombre de 3,4-bisindolylmaléimides possède une activité inhibitrice des protéine-kinases. Les 3-isothiazolone-1,(1)-(di)oxydes pouvant être considérées comme des analogues de la maléimide, la fonctionalisation des 5-chloro- et 4,5-dichloro-3-isothiazolone 1,(1)-(di)oxydes par des réactions de couplage palladocatalysé de Suzuki-Miyaura, permet d'accéder aux analogues “thia” des 3,4-bisindolylmaléimides. La synthèse de sulfonamides primaires tels que les dérivés 4-(hétéro)aryl substitués du benzènesulfonamide comme inhibiteurs potentiels de l'anhydrase carbonique, a également été envisagée dans ce travail.Une collection de matériaux hybrides constitués de nanoparticules de palladium adsorbées sur des nanostructures de carbone a été préparée et testée dans des réactions de couplages palladocatalysés, comme catalyseurs en milieu hétérogène. Le plus efficace d'entre eux, associant des nanoparticules de palladium stabilisées par le dodécanethiol et adsorbées sur des nanotubes de carbones “multi-walled”, a été employé afin de préparer vingt-quatre nouveaux dérivés 4-(hétéro)aryl substitués du benzènesulfonamide. L'échec de l'utilisation de ce catalyseur dans les reactions de fonctionalisation des isothiazolone-1,(1)-(di)oxydes nous a contraints à employer un catalyseur plus conventionnel, le PdCl2(dppf)•CH2Cl2.Le dernier volet de ce projet visait à concevoir des catalyseurs à base de nanoparticules de palladium encapsulées dans des nanofibres de carbone “grafitisées” (nanoréacteurs). Une série de nanoréacteurs a pu être préparée et nous avons étudié l'effet du confinement généré à l'intérieur de la nanofibre, sur la réaction palladocatalysée de Suzuki-Miyaura3,4-bisindolylmaleimides possess an inhibitory activity against protein kinase. Because 3-isothiazolone-1,(1)-(di)oxide can be considered as maleimide analog, 5-chloro and 4,5-dichloro-3-isothiazolone-1,(1)-(di)oxide were functionalised using a palladium-catalysed Suzuki-Miyaura cross-coupling reaction achieving the “thia” analogs of 3,4-bisindolylmaleimides. We were also interested in the preparation primary sulfonamides such as 4-(hetero)aryl substituted benzenesulfonamides as carbonic anhydrases inhibitors.A series of hybrid materials comprising palladium nanoparticles adsorbed on carbon nanostructures has been prepared and tested as heterogeneous catalysts of palladium-mediated cross-coupling reactions. The best catalyst, resulting in palladium nanoparticles stabilised by dodecanethiol adsorbed on multi-walled carbon nanotubes, was employed in Suzuki-Miyaura reactions for the preparation of twenty-four new 4-(hetero)aryl substituted benzenesulfonamides. As this catalyst failed in the functionalisation of isothiazolone-1,(1)-(di)oxides, this latter was realised using a more conventional catalyst, PdCl2(dppf)•CH2Cl2.A last part of the project aimed to the conception of catalysts made of palladium nanoparticles encapsulated in graphitised carbon nanofibres (nanoreactors). We prepared a series of nanoreactors and we studied the effect of the confinement inside the nanofibre channel on the Suzuki-Miyaura cross-coupling reaction
13
Scavella, Giovanni <1973>. « Sintesi di complessi di palladio (0) e palladio (II) con leganti tiopiridinici con sostituenti antracenici ». Master's Degree Thesis, Università Ca' Foscari Venezia, 2021. http://hdl.handle.net/10579/18490.
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14
Bangun, Nimpan. « NMR study of palladium methoxide and palladium carbomethoxide complexes ». Thesis, This resource online, 1993. http://scholar.lib.vt.edu/theses/available/etd-12052009-020137/.
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15
Gustafsson, Nils. « Uppsala Konstmuseum : Le Corbusier vs. Palladio ». Thesis, KTH, Arkitektur, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-145881.
Texte intégralRésumé :
Två av arkitekturhistoriens främsta teoretiker, Andrea Palladio (1508-80) och Le Corbusier (1887-1965), är goda representanter för arkitekturens två huvudgrenar; klassicismen och modernismen. Samtidigt som arkitekterna i mycket utgör varandras motpoler, verkade de båda för strikta ideal beträffande hur god arkitektur skall utföras. Deras respektive avtryck i historien bör inte passeras onämnda i den hastigaste av sammanfattningar; palladianismen användes som stilbegrepp fram tills på 1920-talet då Le Corbusiers läror tog avstamp för att alltjämt hemsöka oss i dagens härskandenyfunktionalism. Idén att ställa dessa giganter mot varandra, jämföra deras huvudsakliga ståndpunkter och söka sammanföra dessa i en ny form av kompositstil, väcktes efter en inventering av den plats som projektet är avsett att behandla. Närområdet kring platsen intill Fyrisån i Uppsala, erbjuder en rad arkitektoniska stilar från 1800-talets empir till modern nyfunkis. Allra närmast ligger ett postmoderntbostadshus och ett modernistiskt kontorskomplex i corbusiansk anda. I denna miljö skall ett nytt museum resas; ett museum som skall sammanföra gammalt och nytt, till innehåll liksom utsida.Two of the foremost theorists in architectural history; Andrea Palladio (1508-80) and Le Corbusier (1887-1965), are both good representatives of architectures two main branches; classicism and modernism. The architects are direct opposites in many aspects. However, they are both advocates of strict rules of producing good architecture. Their imprints in architectural history are inevitable in the briefest of summarys. The concept of putting these architect giants face to face, comparing their main points of theory and trying to combine them in a neverseen composit style, was developed as a result of an inventory of the site. In the surroundings of the Fyris River in central Uppsala, there is a vast amount of architectural styles, reaching from early 19th century neo-classicism to modern day neo-modernmism. Closest to the site, there is a post-modern residential building complex and some modernistic office buildings in true corbusian spirit. In these invironments, a new museum will be risen, a house of the new and the old, inside and outside.
16
El, Allam Driss. « Les enthalpies de formation des alliages liquides : palladium-nickel, palladium-gallium, palladium-indium, nickel-gallium, nickel-indium, palladium-nickel-gallium et paladium-nickel-indium ». Aix-Marseille 1, 1989. http://www.theses.fr/1989AIX11239.
Texte intégralRésumé :
A l'aide d'un calorimetre tres haute temperature (1000c
17
Oh, Seung-Hoon. « Low-temperature catalytic oxidation of carbon monoxide over palladium metal, hydrous palladium oxides, and anhydrous palladium oxides ». [Gainesville, Fla.] : University of Florida, 2005. http://purl.fcla.edu/fcla/etd/UFE0013045.
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McNicholl, Ruth-Anne. « A study of hydrogen interactions with palladium and palladium alloys ». Thesis, Queen's University Belfast, 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.334511.
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19
Frey, Karin Marita Grossen Johannes Michael. « Untersuchung der Korrosion von Silber, Palladium und Silber-Palladium-Legierungen / ». [S.l : s.n.], 1987. http://www.ub.unibe.ch/content/bibliotheken_sammlungen/sondersammlungen/dissen_bestellformular/index_ger.html.
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Pauley, Cassandra C. « Alexander Pope's Opus Magnum as Palladian Monument ». [Tampa, Fla. : s.n.], 2003. http://purl.fcla.edu/fcla/etd/SFE0000082.
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21
Kim, Jeha. « Structural and elastic properties of silver-palladium and copper-palladium superlattices ». Diss., The University of Arizona, 1993. http://hdl.handle.net/10150/186275.
Texte intégralRésumé :
I prepared Ag/Pd and Cu/Pd superlattices using both sputtering and molecular beam epitaxy. For the Ag/Pd (t(Ag):t(Pd) = 1:1) superlattices, I observed two distinctive behaviors in the structural coherence length ξ as a function of modulation wavelength Λ. Using Brillouin light scattering (BLS) I observed a 50% enhancement of the shear elastic constant c₅₅ and a 16% increase of c₁₁ with decreasing Λ. Annealing study showed that a high structural order of the films in the growth direction was strongly correlated to the increase of c₅₅. For the 3:1 and 1:3 Ag/Pd samples, I also observed a monotonic increase of the Rayleigh velocity υ(R) (or c₅₅) with decreasing Λ and similar behavior in the structural coherence length to the 1:1 samples. In conclusion, the recrystallization of the alloy and the formation of extended interfaces by intermixing at the Ag-Pd interfaces are responsible for a large enhancement of c₅₅. Using BLS for the Cu/Pd superlattices, I observed a 24% decrease of c₅₅ as Λ was decreased to ∼30-40 Å, followed by a rapid increase for smaller Λ. The observed homogeneous strain in the growth direction showed a strong relationship with c₅₅. The strain was localized at the interface and the Cu/Pd films were in compressive stress for Λ < 38 Å. In conclusion, a localized strain at the interfaces in Cu/Pd is related to the softening in c₅₅. The measurements of in-plane lattice spacing d[220] indicated a structural transformation of the films at Λ = 14 Å from an incoherent to a coherent structure. However, the in-plane strain did not show any relationship with the softening of c₅₅. For single crystalline Cu/Pd superlattices, well-defined RHEED streaks showed incommensurate growth of Cu(111) on Pd(111) layer. The measured shear elastic constant c₅₅ showed a 26% decrease with respect to the largest Λ film with a peak at Λ ≃ 40 Å. Unlike the sputtered films, while c₅₅ decreases by 26% with decreasing Λ, the Cu/Pd films show no change in d(avg)[111] for Λ > 40 Å. I observed no in-plane anisotropies in υ(R) as predicted from theory for single crystal films.
22
Cappello, Nora. « Palladio e Vicenza : a construção de uma cidade através de seus edifícios ». Universidade de São Paulo, 2009. http://www.teses.usp.br/teses/disponiveis/18/18142/tde-25052009-144939/.
Texte intégralRésumé :
A presente pesquisa pretende, através da realização de um estudo dos projetos de Andrea Palladio para palácios na cidade de Vicenza, identificar na obra do arquiteto as possíveis implicações advindas das viagens por ele feitas à cidade de Roma. A pesquisa também procura aprofundar o entendimento do processo de projeto do arquiteto, entender quais são as diferenças e as semelhanças de composição entre os projetos dos palácios, entender de que maneira Palladio vê e compõe a cidade, qual a sua relação com um traçado urbano preexistente, já configurado, no qual os edifícios devem ser inseridos.This research intends to, through the study of Andrea Palladio\'s palaces projects at Vicenza, identify in the architect\'s work, possible implications which came form his trips to Rome. The research also tries to deepen the comprehension of the process of the architect\'s project; to understand compound\'s differences and similarities between the projects of the palaces; to understand how Palladio sees and compounds the city; the relationship between Palladio and a pre-existent urban plan, already shaped, in which buildings must be introduced.
23
Zuideveld, Martin Alexander. « Solvolysis of palladium-carbon bonds in palladium(II) complexes containing diphosphine ligands ». [S.l. : Amsterdam : s.n.] ; Universiteit van Amsterdam [Host], 2001. http://dare.uva.nl/document/60731.
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Powroźnik, Paulina. « Sensing mechanism in semiconducting hybrid structures for DMMP detection ». Doctoral thesis, Katowice : Uniwersytet Śląski, 2020. http://hdl.handle.net/20.500.12128/15206.
Texte intégralRésumé :
W ostatnich dwóch dekadach, w związku ze wzmożoną aktywność terrorystyczną,
wzrosło zainteresowanie badaniami czujników bojowych środków trujących, w szczególności
sarinu. Ze względu na wysoką toksyczność sarinu, w praktyce laboratoryjnej stosowany jest
związek o podobnej budowie chemicznej - dymetylo metylofosfonian (DMMP). Większość
prac dotyczących wykrywania DMMP skupia się na poszukiwaniu materiałów czułych na ten
związek chemiczny i ich modyfikacji w celu uzyskania jak najlepszych parametrów czujnika.
Odpowiednie zaprojektowanie urządzenia o wysokiej czułości i selektywności, a jednocześnie
o niskich kosztach produkcji i eksploatacji, wymaga dogłębnej znajomości mechanizmów
oddziaływania wykrywanego gazu z materiałem czułym chemicznie. W przypadku DMMP,
mechanizmy te zostały zbadane dla powszechnie stosowanych w czujnikach gazów
półprzewodzących tlenków metali. Wadami tych materiałów są brak selektywności i wysokie
temperatury pracy. Z uwagi na to, testowane są również materiały organiczne o niskich
temperaturach pracy i wyższej selektywności. Jedną z szeroko stosowanych w elektronice, w
tym w czujnikach gazów, grup półprzewodników organicznych są ftalocyjaniny. Kilka prac
sygnalizowało czułość ftalocyjanin względem DMMP, jednak mechanizm sensorowy nie został
wyczerpująco opisany.
Celem tej pracy było opracowanie metodologii badania mechanizmów sensorowych
i zastosowanie jej do opisania mechanizmów wykrywania DMMP przez ftalocyjaniny oraz
struktury hybrydowe oparte o ftalocyjaniny, pallad i tlenek palladu. Zastosowana metodologia
składała się z części teoretycznej i eksperymentalnej. W części teoretycznej wykorzystano
metody chemii kwantowej do zamodelowania adsorpcji DMMP na badanych strukturach
sensorowych. Do weryfikacji wyników teoretycznych posłużyły metody eksperymentalne,
takie jak: spektroskopie fotoemisyjne (XPS i UPS), spektroskopia termodesorpcji oraz pomiar
odpowiedzi sensorowych metodą rezystancyjną.
Badania zostały wykonane dla dwóch grup struktur: dla ftalocyjaniny wodorowej
(H2Pc) z palladem (Pd) i tlenkiem palladu (PdO) oraz dla ftalocyjanin metali. W pierwszej
kolejności określono mechanizm sensorowy dla struktury H2Pc/Pd/PdO, która wykazała
czułość na DMMP w temperaturze pokojowej. Wyniki modelowania teoretycznego wykazały,
że DMMP adsorbuje na H2Pc poprzez oddziaływania fizyczne wzmacniane przez pallad
zarówno w postaci metalicznej, jak i w postaci tlenku palladu. Oddziaływanie to wywołuje
znaczną zmianę momentu dipolowego układu adsorbent-adsorbat, z niewielkim przesunięciem
ładunku elektrycznego. Wyniki teoretyczne zostały potwierdzone doświadczalnie w badaniu
składu chemicznego powierzchni struktury H2Pc/Pd/PdO i pomiarach odpowiedzi sensorowej.
Następnie, w celu optymalizacji struktury sensorowej, zanalizowano mechanizm
oddziaływania DMMP z ftalocyjaninami metali, w których DMMP tworzy wiązanie poprzez
tlen z centralnym atomem ftalocyjaniny. W wyniku wstępnych obliczeń teoretycznych wybrano
ZnPc do szczegółowej analizy mechanizmu sensorowego. Modelowanie adsorpcji DMMP na
ZnPc pokazało, że następuje transfer elektronów z cząsteczki DMMP do ftalocyjaniny, przy
czym ładunek pozostaje w większości zakumulowany na wierzchniej monowarstwie ZnPc, co
prowadzi do powstania silnego dipola powierzchniowego. Wyniki teoretyczne zostały
potwierdzone badaniami zmian elektronowych i chemicznych w cienkiej warstwie ZnPc. Dodatkowo, dla ftalocyjanin metali potwierdzono w modelowaniu teoretycznym analogię
mechanizmu sensorowego dla sarinu i DMMP.
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Todorova, Mira. « Oxidation of Palladium surfaces ». [S.l.] : [s.n.], 2004. http://deposit.ddb.de/cgi-bin/dokserv?idn=971639868.
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Williamson, Anna Maria. « Studies on novel palladium ». Thesis, Imperial College London, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.252246.
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Sparkes, Robert P. « Carbocations in palladium crystals ». Thesis, University of Oxford, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.249213.
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Sukirthalingam, Sukanthini. « Palladium catalysed cyclisation processes ». Thesis, Queen's University Belfast, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.335444.
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Morris, James Alan. « Palladium-ruthenium bimetallic cascades ». Thesis, University of Leeds, 2004. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.405707.
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Ostovar, Peyman. « Palladium-catalysed neuroleptic synthesis ». Thesis, Imperial College London, 1989. http://hdl.handle.net/10044/1/47601.
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Rojas, Anthony J. (Anthony Jose). « Palladium reagents for bioconjugation ». Thesis, Massachusetts Institute of Technology, 2018. http://hdl.handle.net/1721.1/120905.
Texte intégralRésumé :
Thesis: Ph. D., Massachusetts Institute of Technology, Department of Chemistry, 2018.Cataloged from PDF version of thesis.
Includes bibliographical references.
physicochemical properties in comparison to their linear counterparts. Here we detail a method for a divergent macrocyclization of unprotected peptides by crosslinking two cysteine residues with bis-palladium organometallic reagents. These synthetic intermediates are prepared in a single step from commercially available aryl bis-halides. Two bioactive linear peptides with cysteine residues at i, i + 4 and i, i + 7 positions, respectively, were cyclised to introduce a diverse array of aryl and bi-aryl linkers. These two series of macrocyclic peptides displayed similar linker-dependent lipophilicity, phospholipid affinity, and unique volume of distributions. Additionally, one of the bioactive peptides showed target binding affinity that was predominantly affected by the length of the linker. Collectively, this divergent strategy allowed rapid and convenient access to various aryl linkers, enabling the systematic evaluation of the effect of appending unit on the medicinal properties of macrocyclic peptides. Chapter 2: We report the use of a sulfonated biarylphosphine ligand (sSPhos) to promote the chemoselective modification of cysteine containing proteins and peptides with palladium reagents in aqueous medium. The use of sSPhos allowed for the isolation of several air-stable and water-soluble mono- and bis-palladium reagents, which were used in an improved protocol for the rapid S-arylation of cysteines under benign and physiologically relevant conditions. The cosolvent-free aqueous conditions were applied to the conjugation of a variety of biomolecules with affinity tags, heterocycles, fluorophores, and functional handles. Additionally, bispalladium reagents were used to perform macrocyclization of peptides bearing two cysteine residues. Chapter 3: The synthesis of palladium oxidative addition complexes of unprotected peptides is described. Incorporation of 4-halophenylalanine into a peptide during solid phase peptide synthesis allows for subsequent oxidative addition at this position of the unprotected peptide upon treatment with a palladium precursor and suitable ligand. The resulting palladium-peptide complexes are solid, storable, water-soluble, and easily purified via high-performance liquid chromatography. These complexes react rapidly with thiols at low micromolar concentrations in an aqueous buffer, offering an efficient method for bioconjugation. Using this strategy, peptides can be rapidly functionalized with small molecules to prepare modified aryl thioether sidechains. Additionally, peptide-peptide and peptide-protein ligations are demonstrated under dilute aqueous conditions.
by Anthony J. Rojas.
Ph. D.
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Li, Meiling. « Palladium catalysed allene carbocyclisation ». Thesis, University of Oxford, 2010. http://ora.ox.ac.uk/objects/uuid:747420b6-c11f-451c-83c7-fa9fca5f7752.
Texte intégralRésumé :
In this thesis, firstly, a Pd-catalysed diastereoselective carbocyclisation of allenes with aryl halides or vinyl iodides was designed and developed to form arylative or vinylative spirolactam compounds. High yields and diastereoselectivities were obtained in the presence of Pd2(dba)3/dppe and K2CO3 in DMSO at 70 °C, particularly when spiropiperidin-2-ones were formed. The method is simple to perform and broad in scope. Having established the diastereoselective methodology for the arylative or vinylative allene carbocyclisation, a Pd-catalysed enantioselective version was developed by using bisoxazolines as chiral ligands. Aryl halides and vinyl iodides were investigated in this carbocyclisation. High yields and enantioselectivities were obtained in the presence of Pd(OAc)2, a bisoxazoline ligand L7d derived from L-isoleucine and Ag3PO4 in 1,2-dichloroethane at 70 °C. No olefin isomerisation was observed when cis-vinyl iodides were used. The method is mild, efficient and broad in scope. A palladium catalysed diastereoselective allene carbocyclisation reaction was developed via enamine catalysis and palladium catalysis, which allows for the efficient carbocyclisation of formyl or ketone allenes. Good yields and high diastereoselectivities were obtained in the presence of Pd(OAc)2 and pyrrolidine in toluene at 60 °C when formyl allenes were investigated. The cyclisation is diastereoselective and can also performed as a catalytic asymmetric reaction by using prolinol derivatives as chiral catalysts. Good yields and high diastereo- and enantioselectivities were obtained in the presence of catalyst (S)-L19. Additionally, a boronic acid catalysed ene carbocyclisation of acetylenic dicarbonyl compounds was developed. An attempted transesterification of a β-ketoester substrate bearing a pendent terminal alkyne substituent at the β-position led to the discovery of an efficient 3-nitrobenzeneboronic acid catalysed ene carbocyclisation of acetylenic dicarbonyl compounds. The reaction is easy to perform, efficient, broad in scope and provides a convenient transition metal-free alternative to existing catalytic protocols.
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Sadig, Jessie E. R. « Palladium-catalysed heterocycle synthesis ». Thesis, University of Oxford, 2012. http://ora.ox.ac.uk/objects/uuid:c9608957-d215-4a15-87e3-5871c1391946.
Texte intégralRésumé :
Chapter 1 is a literature review of selected palladium-catalysed aryl C-N and C-S bond forming reactions. The application of these reactions to the synthesis of heterocycles is also discussed. Chapter 2 highlights the importance of the benzimidazole motif and gives a brief discussion of the existing routes to this scaffold. The utility of N-(o-halophenyl)imidoyl chlorides and imidates as precursors to heterocycles is demonstrated in a palladium-catalysed reaction with N-nucleophiles to afford benzimidazole products. Chapter 3 provides a brief introduction to the synthesis of benzothiazoles and describes efforts towards the use of our established substrates for the preparation of these heterocycles. This is achieved via reaction of N-(o-chlorophenyl)imidoyl chlorides with a sulfur nucleophile in a metal-free process. Chapter 4 is a literature review of palladium-catalysed carbonylation chemistry with specific focus on aminocarbonylation and thiocarbonylation reactions of aryl halides. Heterocycle syntheses which employ such carbonylative methods are also discussed. Chapter 5 describes existing protocols for the synthesis of quinazolinones. A novel palladium-catalysed synthesis of these heterocycles from the reaction of our imidate substrates with an amine and carbon monoxide is described. This further demonstrates their utility as general heterocycle precursors
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Hollingworth, Charlotte. « Palladium mediated allylic fluorination ». Thesis, University of Oxford, 2013. http://ora.ox.ac.uk/objects/uuid:8c61b9e9-b143-4c5e-b151-7e62bf4ecc03.
Texte intégralRésumé :
In this thesis, the construction of the allylic fluorides under palladium catalysis was investigated. Chapter 1 provides a general introduction to organofluorine compounds and the use of palladium for the formation of both Csp2- and Csp3-F bonds. The aims of the thesis are presented. In Chapter 2 the identification that a p-nitrobenzoate is the optimum leaving group under Pd-catalysis to give allyl fluorides is described. A range of allylic fluorides was synthesized in 35->95% yield using the nucleophilic fluorinating reagent, TBAF(tBuOH)4. To further develop this transformation we have examined the effect of a variety of leaving groups and phosphine ligands. This methodology led to the development of the first transition metal mediated C-18F bond formation. The development of Ir-catalysed fluorination of allylic carbonates to give allylic fluorides is also discussed. This system provided access to branched, E- and Z-linear allylic fluorides in a regioselective manner. This methodology was also translated to 18F radiochemistry. In Chapter 3 the synthesis of allylic fluorides via a C-H functionalisation with Pd and nucleophilic source of fluorine was investigated. Comprehensive screening of Pd sources, fluoride reagents and additives was performed. The presence of a quinone was found to be crucial for this transformation. Chapter 4 describes the synthesis and characterization of a series of allylpalladium(II) complexes and their subsequent reactivity towards a range of electrophilic fluorination reagents. Chapter 5 gives full experimental procedures and characterization data for all compounds.
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Setayandeh, Samaneh S. « Hydrogen Properties in Palladium ». Thesis, Griffith University, 2021. http://hdl.handle.net/10072/404154.
Texte intégralRésumé :
In this project the palladium-hydrogen system was investigated, using computational and experimental approaches. Computational modelling, employing ab initio calculations based on density functional theory (DFT), were done with the Quantum Espresso package, to investigate the electronic and phonon properties of PdH and its superabundant vacancy phase (Pd3VacH4), assuming that octahedral or tetrahedral lattice interstices are occupied by hydrogen, and to relate these to important physical properties, in particular the atomic volume of hydrogen in Pd and the superconducting transition temperature of PdH.
The driver for the computational part of this project was the history of DFTbased publications in the literature predicting such widely different phonon band structures that confident interpretations of the results really could not be made. Therefore, a systematic approach was followed to compare the calculated electron and phonon properties of PdH and Pd3H4 with six different DFT schemes, within the harmonic approximation. The results highlighted the excellent agreement for the electron band structure and the sensitivity of the phonon properties to the details of the schemes employed, and also confirmed the need to include anharmonicity of the H potential to obtain realistic phonon results.
The calculations predicted dynamic instability for octahedral Pd3VacH4, although the calculated lattice constant agreed with the estimated zerotemperature experimental value. This structure requires new calculations accounting for anharmonicity. The calculated lattice constant for Pd3VacH4 in the tetrahedral case was larger than any experimental value, so this alternative, while dynamically stable, is certainly not observed.
While the absolute lattice constant of PdH varied considerably between DFT schemes, it was found that the partial atomic volume of H in Pd, a relative measure, was rather robust against differing computational approaches. A significant discrepancy was demonstrated between the average DFT predictions for the atomic volume assuming octahedral-only interstitial occupancy and that calculated from neutron diffraction measurements on Pd and PdHx. Calculations for PdH with mixed octahedral and tetrahedral occupancy showed that PdH containing around 20% tetrahedral H would have the correct atomic H volume.
Within the harmonic approximation, the calculated superconducting transition temperature of octahedral PdH varied by a factor of nearly three across the six DFT schemes employed. This shows that a reliable DFT approach is needed before attempting to account for anharmonicity of the H potential. In the tetrahedral case, less discrepancy was observed between the characteristic measures of superconductivity, due to the smaller contribution of high-frequency optical branches to the electron-phonon coupling parameter, but the actual values predicted for the transition temperature should be relatively reliable because the tetrahedral site, being relatively small, should be more nearly harmonic than the octahedral site. The transition temperatures calculated for tetrahedral PdH were higher than those measured experimentally, making partial tetrahedral occupancy an interesting possibility from the superconductivity point of view.
For the experimental part of this project, high-resolution gravimetry was used to survey the pressure-composition behaviour of PdHx and PdDx formed above their critical points and cooled to room temperature, to determine if this preparation route leads to extra hydrogen and deuterium absorption compared to passage through the two-phase region. It was found that supercritical absorption shifted the low-pressure portion of the desorption isotherm towards higher concentration. However, the isotherms were shifted towards the expected H/D concentration by cycling, apparently due to introducing misfit dislocations in the sample. Hydriding the sample at room temperature and heating it to 300 ℃ under pressure instead of first heating to 300 ℃ and then loading with hydrogen unexpectedly shifted the supercritcal isotherms at 300℃ to lower pressure, pointing to a further and previously unobserved influence of defects on the absorption-desorption behaviour.Thesis (PhD Doctorate)
Doctor of Philosophy (PhD)
School of Environment and Sc
Science, Environment, Engineering and Technology
Full Text
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Powell, Luke Haydn William. « Palladium-catalysed enantioselective desymmetrisations ». Thesis, University of Bath, 2005. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.425803.
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Capistrano, Gradisca de Oliveira Werneck de. « A vila nos textos de Alberti e Palladio ». Universidade de São Paulo, 2014. http://www.teses.usp.br/teses/disponiveis/102/102132/tde-08012015-153002/.
Texte intégralRésumé :
Alberti e Palladio foram dois dos principais nomes na constituição dos modelos de vilas que caracterizaram o Renascimento italiano. Enquanto Alberti, em seu De re aedificatoria, estabeleceu as bases e a fundamentação teórica sobre o tema, no início do período, Palladio com I Quattro Libri dell\'Architettura, sistematizou um repertório formal que o tornou responsável pela difusão do modelo ao redor do mundo. Tendo-se em vista a importância da contribuição de ambos os autores e considerando que Palladio leu o tratado de Alberti, foi feito um estudo comparativo desses dois modelos de vila, visando detectar suas aproximações e divergências. Partindo-se da exposição do tema no corpo dos tratados e passando pelas definições do termo vila são abordados diversos aspectos da argumentação dos dois autores. Considerando a grande contribuição de Alberti e Palladio no campo da representação gráfica da arquitetura e do processo intelectual de projeto, foi discutida a relação desses dois temas, tanto na composição quanto na apresentação das vilas (especificamente no tratado paladiano). São analisadas ainda, o estabelecimento das hierarquias que são utilizadas na adequação das vilas à classes sociais de seus proprietários, a setorização proposta na organização da vila e da casa de vila e, por fim, a compartimentação desses edifícios. Mesmo considerando que os dois autores leram Vitruvio, de onde poderiam ter surgido diversos pontos que apresentam em comum, deve-se considerar que, para o projeto e a concepção das vilas, o texto de Vitruvio foi de pouca utilidade. Sendo assim, é surpreendente e também reveladora a semelhança que se percebe nas vilas de Alberti e Palladio. Em diversos trechos dos tratados, os discursos são tão próximos que parecem complementares, como também se pode utilizar projetos paladianos para exemplificar indicações teorizadas por Alberti. Esse trabalho não pretende esgotar o argumento, mas verificar a existência de uma relação entre a vila para ambos e, com essa relação mostrando-se tão forte, superaram-se todas as expectativas iniciais.Alberti and Palladio were two of the leading names in the establishment of models for villas, which characterized the Italian Renaissance. At the beginning of the Renaissance period, Alberti in his De Re Aedificatoria established the foundation and the theoretical background of the subject. Afterward Palladio, in his I Quattro Libri Dell\'Architettura, systematized a set of formal rules that made him responsible for the diffusion of a general model of villa around the world. Bearing in mind the importance of the contribution of both authors and considering that Palladio read Alberti´s treatise, we made a comparative study of these two models of villa, in order to detect their similarities and differences. Several aspects of both authors\' arguments are addressed, starting from the development of the subject in the body of the treaties and including the different definitions of the term villa. Given the important contributions of Alberti and Palladio in the field of graphic representation of architecture and intellectual process of project, the relationship between these two topics was discussed, both in the composition and in the presentation of villas (specifically in the Palladian treaty). Furthermore, we analyzed the establishment of hierarchies used in adapting the villas to the social class of their owners; we investigated the sections proposed for the organization of the villa and, finally, we examined the partitions of these buildings. Although the two authors read Vitruvius, who could have provided them with a common theoretical background, it must be stressed that Vitruvius´s writings were of little use in the conception and project of villas. Therefore, it is surprising and revealing the resemblance noticed in the villas of Alberti and Palladio. In different parts of the treaties, discussions are so close that they seem complementary. Besides, Palladian projects can also be used to exemplify indications theorized by Alberti. The present study does not bring to an end the discussion; instead, it intends to check the existence of a relationship between the ideas of in both authors. We demonstrate that this relationship is actually strong, overcoming all the initial speculations of tight connections.
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López, Avilés Agustín. « Palladine of England (1588) Translated by Anthony Munday ». Doctoral thesis, Universidad de Alicante, 2017. http://hdl.handle.net/10045/73030.
Texte intégralRésumé :
Edición crítica en inglés de Palladine of England, libro de caballerías traducido al inglés por Anthony Munday en 1588 a través de su versión francesa L'Histoire Palladienne, de 1555. El libro original, ibérico y de autor anónimo, que Claude Colet tradujo al francés, es Don Florando de Inglaterra (1545). Esta edición crítica proporciona una introducción a la época, género y prácticas traductológicas de Munday; un seguimiento histórico de la obra, descripción bibliográfica, transcripción y edición del texto original con notas eruditas; y glosario, emendaciones y un apéndice de notas traductológicas.
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Tong, Xiu Qiang. « Lattice strain induced (Gorsky effect) diffusion of hydrogen in palladium and palladium alloys ». Thesis, Queen's University Belfast, 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.334683.
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Rayee, Quentin. « Dépôts électrochimiques d’argent, de palladium et d’alliages argent-palladium en solvants eutectiques profonds ». Doctoral thesis, Universite Libre de Bruxelles, 2020. http://hdl.handle.net/2013/ULB-DIPOT:oai:dipot.ulb.ac.be:2013/303218.
Texte intégralRésumé :
Le recours aux solvants eutectiques profonds se présente comme une alternative potentielle aux limitations rencontrées en milieux aqueux pour la réalisation de dépôts électrochimiques. La transposition des procédés électrochimiques des milieux conventionnels vers ces nouveaux milieux n’est pas immédiate et nécessite d’entreprendre des études fondamentales visant à comprendre l’impact de la nature des solvants eutectiques profonds sur différents processus survenant à l’interface électrochimique. Dans cette optique, le présent travail examine les mécanismes impliqués dans la formation de dépôts d’argent, de palladium et du mélange Ag-Pd en solvants eutectiques profonds à l’aide de plusieurs techniques voltampérométriques (voltampérométries cyclique, différentielle, alternative, hydrodynamique, à balayage linéaire) et de mesures chronoampérométriques. Le choix du dépôt d’argent a été retenu comme système modèle et a été étendu à la réalisation d’alliage Ag-Pd qui présente un intérêt plus appliqué. Les solvants eutectiques profonds sélectionnés pour cette recherche sont obtenus en mélangeant du chlorure de choline avec de l’urée (ChCl-U) ou avec de l’acide oxalique (ChCl-Ox). Le comportement électrochimique de AgCl en ChCl-U est fortement affecté par la nature de l’électrode. Sur carbone et platine, une importante surtension pour le dépôt à 3D est requise, alors qu’aucune surtension n’est nécessaire sur électrode d’or en raison d’un processus de dépôt à 2D (dépôt en soustension) de l’argent sur l’or. Ce mécanisme de dépôt en sous-tension est peu sensible à la nature du solvant eutectique profond et très similaire à celui obtenu en solution aqueuse avec une concentration équivalente en chlorures. Le recours à des monocristaux a permis d’examiner l’influence de la cristallographie sur le dépôt en sous-tension. Une attention particulière a été portée à la présence de thiourée en milieu ChCl-U et celle-ci affecte profondément les dépôts métalliques d’Ag en modifiant la coordination des espèces Ag(I) et l’adsorption des espèces constitutives du ChCl-U à la surface d’une électrode d’or. Les mesures voltampérométriques du PdCl2 en ChCl-U ont permis de distinguer quatre régions en potentiel où ont lieu respectivement (des potentiels les plus positifs vers les plus négatifs) un dépôt en sous-tension confirmé par des mesures de désorption oxydative de CO, un dépôt à 3D, la formation d’hydrure de palladium (PdHx) et, à des potentiels bien inférieurs, un processus d’inhibition du dépôt. L’utilisation du ChCl-Ox a mis en évidence que la formation de PdHx dépendait du pH apparent du solvant eutectique. L’étude du mélange de AgCl et de PdCl2 a révélé la coexistence de phases distinctes associées à des alliages de différentes compositions formés lors du dépôt électrochimique. Les proportions entre les différentes phases sont très sensibles aux conditions de température, potentiel de dépôt et concentration des précurseurs métalliques, et l’influence de ces différents paramètres est discutée en détail. De plus, un processus de remplacement galvanique de l’argent par le palladium a également été mis en évidence avec l’appui de mesures XPS.Doctorat en Sciences
info:eu-repo/semantics/nonPublished
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Barrett, Anne Rachelle. « The Consul Smith Palladio at Virginia Commonwealth University and the American Renaissance / ». VCU Scholars Compass, 2006. http://hdl.handle.net/10156/1239.
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Yang, Zhiqiang. « Preparation of palladium, palladium sulfide, cadmium selenide nanoparticles and magnesium oxychloride, magnesium hydroxide nanorods ». Diss., Manhattan, Kan. : Kansas State University, 2008. http://hdl.handle.net/2097/891.
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Vicente, Aurélie. « Hydrogénation du citral sur catalyseurs bimétalliques supportés rhodium-germanium, palladium-germanium et palladium-étain ». Poitiers, 2008. http://www.theses.fr/2008POIT2338.
Texte intégralRésumé :
Ce travail est consacré à la préparation de catalyseurs bimétalliques supportés Rh-Ge, Pd-Ge et Pd-Sn pour l’hydrogénation sélective du citral en alcools a,b-insaturés. Pour les catalyseurs à base de Rh, l’étude porte sur l’influence de la nature des sels précurseurs utilisés. L’existence d’interactions entre les deux métaux des différents systèmes bimétalliques est mise en évidence par diverses techniques de caractérisation (EDX, réaction modèle de déshydrogénation du cyclohexane, RTP sous H2, IRTF de CO adsorbé). La réaction d’hydrogénation sélective du citral a montré qu’il est possible de modifier profondément les propriétés de ces métaux par les ajouts Ge et Sn, et ainsi former des alcools insaturés. L’adsorption de CO suivie par IRTF sur les catalyseurs Rh-Ge/TiO2 révèle la formation d’espèces Rh≥1+ avec ajout de Ge, lesquelles permettraient l’activation de la fonction carbonyle du citral. De plus, la présence de chlore issu des sels précurseurs semble être favorable à la formation de ces espèces Rh≥1+ sur ces systèmes bimétalliques. Pour le palladium, une bonne sélectivité en alcools insaturés est obtenue lorsqu’il y a formation d’un alliage de type Pd3M (avec M = Ge ou Sn), formation mise en évidence par différentes caractérisations (RTP et XPS). Cet alliage induit un transfert d’électron de Sn vers Pd constaté aussi bien par IRTF que par XPS, qui peut expliquer une adsorption favorisée de la liaison C=O du citralThis work was devoted to the preparation of supported bimetallic Rh-Ge, Pd-Ge and Pd-Sn catalysts for the selective hydrogenation of citral to its corresponding a,b-unsaturated alcohols. In the case of Rh catalysts, the influence of Rh and Ge salt precursors has been studied. The existence of interactions between the two metals for the different bimetallic systems has been highlighted by several characterization methods (EDX, cyclohexane dehydrogenation reaction, TPR under H2, FTIR of adsorbed CO). The reaction of selective hydrogenation of citral showed that the addition of Ge or Sn to Rh and Pd allowed one to strongly modified the catalytic properties of these metals. The adsorption of CO followed by FTIR on Rh-Ge/TiO2 revealed the formation of Rh≥1+ species due to Ge addition. These species would activate the carbonyl group of citral. Moreover, the presence of chlorine resulting from precursor salts seemed favourable to the formation of these Rh≥1+ species. In the case of Pd catalysts, the different characterizations (TPR and XPS) proved the formation of Pd3M alloy (with M = Ge or Sn). This alloy induced an electron transfer from Sn to Pd, evidenced by FTIR and XPS. The formation of these Pd-Snd+ sites could then explain a favoured adsorption of the carbonyl group of citral, which leads to high selectivity in unsaturated alcohol
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Stumpp, Monika Maria. « A simetria modular e as villas de Andrea Palladio ». reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2013. http://hdl.handle.net/10183/85180.
Texte intégralRésumé :
Esta tese se propõe a estudar a simetria enquanto recurso compositivo na obra do arquiteto italiano Andrea Palladio. Parte-‐se da hipótese de que a simetria teria facilitado a criação de um sistema arquitetônico flexível, que coordena desdobramentos inventivos, sem comprometer a unidade compositiva. Dessa hipótese derivou a necessidade de verificar a adoção de procedimentos compositivos que comprovassem o uso da simetria por Palladio como base ordenadora de unidade e diversidade, tanto formal como espacial. Para isso são analisados doze edifícios de villas construídos ao longo do século XVI. Ao contrário do que é comumente assumido, o termo “simetria” tem um significado bem mais amplo que a mera disposição especular das partes de um edifício. As origens do termo na arquitetura se encontram no tratado De Architectura libri decem, escrito por Vitrúvio no século I a.C. Em seu primeiro livro, ao definir o termo “simetria”, o autor se refere a unidades modulares articuladas que concatenam as partes de uma obra. Tais unidades modulares são passíveis de subdivisões ou adições, onde as relações de medida asseguram a coordenação do todo e, ao mesmo tempo, abrem espaço à diversidade. Ao longo deste trabalho, esse instrumento foi denominado de “simetria modular, por sua ênfase na comensurabilidade como meio de coordenação no projeto arquitetônico. A análise das obras selecionadas, seguida de sua visão em síntese, demonstrou que Palladio utilizou recursos geométricos, modulares e proporcionais que se relacionam ao conceito de simetria enunciado por Vitrúvio. Percebe-‐se que Palladio formulou um sistema de modulação dimensional que se desdobra em um procedimento de controle geométrico do projeto. A disposição de partes segundo faixas, malhas, medidas proporcionais e espaços concatenados, tanto em planta como em corte, resultou em um conjunto harmônico, cujas partes constituem um todo ordenado por meio da proporção. Desse modo, a definição de simetria proposta por Vitrúvio e retomada por Alberti no século XV, tratando da correspondência entre o todo e as partes, faz-‐se presente na obra de Palladio, que diferentemente de seus antecessores, demonstra sua efetividade como recurso de projeto por meio de um vasto legado de obras executadas. As lições extraídas do uso da simetria nos projetos de Palladio mostram a importância de procedimentos ordenadores como um sistema de controle que potencializa a inventividade. Seu valor como forma de abordar o projeto arquitetônico é tão atual hoje como o foi na Itália do século XVI.This dissertation intends to study simmetry as a design component in the work of the Italian architect Andrea Palladio. It was originated in the assumption that the use of simmetry allowed for the creation of a flexible architectural system, which coordinates inventive movements without threatening the unity of the whole composition. Such hypothesis required the study of design procedures that could support the use of symmetry by Palladio as a frame of order to achieve unity and diversity in form and space at the same time. Therefore, twelve of his villas built in the 16th century are analyzed. In opposition to popular assumption, symmetry has a much larger scope than the simple bilateral arrangement of the parts of a building. The architectural meaning of the term is found in the treatise De Architectura, written by Vitruvius in the 1st century BC. In defining the term in his first book, the author speaks about modular units that coordinate the parts of a building. Such modules can be divided or added, and the ratios among dimensions provide coordination to the whole work and, at the same time, allow for diversity. In the course of this dissertation, this instrument is defined as“modular symmetry” due to its emphasis in commensurability as a means for coordination in architectural design. The individual analysis of Palladio's villas, followed by a synthesis, demonstrated that Palladio used in his design procedures geometrical, modular and proportional approaches related to the concept of symmetry enunciated by Vitruvius. The architect followed a modular system in attributing dimensions which turned into a procedure of geometric control in designing. The ordering of parts in rows and grids, the use of proportional dimensions and the spatial relationship among compartments, both in plan and section, resulted in harmonic ensembles in which parts constitute a whole ordered by proportion. Therefore, the definition of symmetry given by Vitruvius and reassessed by Alberti in the 15th century, dealing with the correspondence between whole and parts, comes up in Palladio's work. Differently from his forerunners, he demonstrates the efficiency of this larger sense of symmetry as a design resource through a great number of buildings. The lessons learned in Palladio's use of symmetry show the importance of ordering procedures as a system of control that strengthens inventiveness in architectural design. Such approach is as valuable today as it was in 16th century Italy.
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Isetta, Giacomo <1991>. « Sintesi e caratterizzazione di nuovi complessi indenilici di Palladio ». Master's Degree Thesis, Università Ca' Foscari Venezia, 2021. http://hdl.handle.net/10579/20135.
Texte intégralRésumé :
Sintesi di nuovi complessi indenilici di palladio con leganti carbenici N-eterociclici e fosfine. Successiva caratterizzazione mediante NMR e prove di catalisi su reazioni di cross-coupling Suzuki-Miyaura in acqua.
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Beyer, Andreas. « Reaktivmembranen aus Polyacrylsäure-Palladium-Verbundsystemen ». [S.l.] : [s.n.], 2001. http://deposit.ddb.de/cgi-bin/dokserv?idn=963799169.
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Markmann, Jürgen. « Mikrostrukturuntersuchungen an kaltgewalztem nanokristallinem Palladium ». Karlsruhe : FZKA, 2005. http://bibliothek.fzk.de/zb/berichte/FZKA7126.pdf.
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Lindh, Jonas. « Palladium(II)-Catalyzed Coupling Reactions ». Doctoral thesis, Uppsala universitet, Avdelningen för organisk farmaceutisk kemi, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-130031.
Texte intégralRésumé :
Sustainable chemical processes are becoming increasingly important in all fields of synthetic chemistry. Catalysis can play an important role in developing environmentally benign chemical processes, and transition metals have an important role to play in the area of green chemistry. In particular, palladium(II) catalysis includes many key features for successful green chemistry methods, as demonstrated by a number of eco-friendly oxidation reactions catalyzed by palladium(II). The aim of the work presented in this thesis was to develop novel and greener palladium(II)-catalyzed coupling reactions. In striving to achieve this aim, the first open-vessel, room-temperature palladium(II)-catalyzed oxidative Heck reaction, using oxygen from the air as the reoxidant of palladium, was developed. In a further investigation of the palladium(II)-catalyzed oxidative Heck reaction, base-free conditions for the transformation were identified and suitable conditions for microwave-assisted oxidative Heck reactions were established. A convenient and low-cost palladium(II)-catalyzed method for the synthesis of styrene derivatives, by coupling arylboranes with vinyl acetate, was developed. The reaction mechanism was studied using ESI-MS, which enabled the detection of cationic palladium intermediates in ongoing productive reactions, and a plausible catalytic cycle was proposed. In an attempt to make the oxidative Heck and the styrene synthesis reactions more attractive from an industrial point of view, conditions for continuous flow synthesis were identified. The results were generally good and rapid synthesis of the desired products was obtained. The first palladium(II)-catalyzed C–P bond-forming Hirao-type reaction, employing arylboranes instead of the commonly used aryl halides, was developed. An ESI-MS study was performed, and a plausible catalytic pathway was suggested. Finally, a novel method for synthesizing aryl ketones from benzoic acids and nitriles, via palladium(II)-catalyzed decarboxylation of the benzoic acids, was established. Further, the reaction mechanism was studied by ESI-MS and a plausible catalytic route presented.
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Zargarian, Davit. « Palladium-catalyzed carbonylation of alkynes ». Thesis, University of Ottawa (Canada), 1992. http://hdl.handle.net/10393/7555.
Texte intégralRésumé :
This thesis describes the palladium-catalyzed carbonylation of alkynes with formic acid. Terminal alkynes react with formic acid in the presence of catalytic amounts of Pd(OAc)$\sb2$ and suitable phosphine ligands (120 psi of CO gas pressure, 100-110$\sp\circ$C) to produce the unsaturated carboxylic acids CR(COOH)=CH$\sb2,$ 1, and (E)-CHR=CH(COOH), 2. The combined yields of 1 and 2 for various R's range from 60 to 90%. The regioselectivity is approximately 90:10 in favour of 1 when R is a phenyl or a straight chain alkyl group; 2 is the favoured product when R is t-Bu and the exclusive one when R is SiMe$\sb3.$ Under similar conditions, internal alkynes react with formic acid to produce the unsaturated carboxylic acids (E)-CR(COOH)=CHR$\sp\prime$, 3, and (E)-CHR=CR$\sp\prime$(COOH), 4, also in 60-90% combined yields. The regioselectivity of this reaction, however, is not as high as for terminal alkynes. Oxalic acid can be used instead of formic acid in both of these reactions. The most suitable phosphine ligands for alkyne hydrocarboxylation in the present system are PPh$\sb3$ and dppb (1,4-bis(diphenylphosphino)butane). In some cases, using a mixture of these two ligands remarkably improves the reaction yields; the implications of such ligand synergism are discussed. On the basis of deuterium labelling studies and other experimental results, a reaction mechanism has been proposed which involves the addition of the O-H bond of formic acid to form a cationic hydrido(alkyne) intermediate. This intermediate is thought to undergo a sequence of reactions, including hydride and CO insertions, to give the acid product and regenerate the active catalyst. Terminal alkynes undergo dicarbonylation upon reacting with formic acid and/or water in a catalytic system consisting of $\rm PdCl\sb2/CuCl\sb2/O\sb2/CO$ (room temperature, atmospheric pressure); the products are monosubstituted maleic anhydrides and the corresponding maleic and fumaric acids in 30-75% combined yields. The product distribution is influenced by both the steric bulk of the alkyne substituent and the amount of water present in the reaction medium. Internal alkynes are unreactive in this system. Among the solvents tested, THF is the most suitable one. Phosphines and phosphites completely inhibit the reaction. In contrast to most systems in which CuCl$\sb2$ acts as the principal oxidant for converting Pd(0) to Pd(II), the role of CuCl$\sb2$ in the present system seems to be secondary to that of oxygen. For instance, modest catalytic turnovers are observed in the absence of CuCl$\sb2$, whereas no catalysis occurs if oxygen is excluded from the system, even in the presence of excess CuCl$\sb2$. These and other observation are rationalized by invoking various oxidation schemes involving oxygen as the main oxidant. The role of CuCl$\sb2$ is thought to be one of facilitating the catalysis by forming a heterometallic Cu/Pd complex.
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Zhao, Jian. « Palladium migrations and aryne annulations ». [Ames, Iowa : Iowa State University], 2007.
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