Dissertations / Theses: 'Organic'

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Vrchotová, Jana. "Organické materiály pro molekulární elektroniku a fotoniku." Doctoral thesis, Vysoké učení technické v Brně. Fakulta chemická, 2019. http://www.nusl.cz/ntk/nusl-403856.

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Organická elektronika je dynamické, rychle se rozvíjející odvětví. Studium nových materiálů pro organickou elektroniku je důležitým úkolem jak z hlediska výkonnosti budoucích zařízení a ekonomičnosti procesů, tak z hlediska vlivu jejich používání na životní prostředí. Deriváty diketopyrrolopyrrolu patří mezi zajímavé materiály, které jsou v posledních letech studovány s ohledem na využití v organické elektronice. Dizertační práce je zaměřena na studium těchto materiálů a jejich jak optickou, tak i elektrickou charakterizaci. Součástí je také zhodnocení jejich potenciální aplikace v organické elektronice a návrhy optimalizace jejich výkonu. Teoretická část práce popisuje současný stav na poli organické elektroniky zaměřený na materiály na bázi diketopyrrolopyrrolu. Následující výsledková část shrnuje podstatné výsledky práce a obsahuje stručný úvod k přiloženým publikacím, včetně zhodnocení vlastního přínosu autora k jednotlivým publikacím. Výsledková část dále sestává z 6 vědeckých publikací, které jsou nedílnou součástí této práce a jsou tematicky propojeny v oblasti organické elektroniky, nových materiálů na bázi diketopyrrolopyrrolu a jejich aplikací. Z formálního hlediska je práce na základě čl. 42 odstavce 1b Studijního a zkušebního řádu VUT koncipovaná jako tematicky uspořádaný soubor uveřejněných prací a prací přijatých k publikaci.

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Češka, Matěj. "Nízkomolekulární materiály pro organickou elektroniku a fotoniku." Master's thesis, Vysoké učení technické v Brně. Fakulta chemická, 2012. http://www.nusl.cz/ntk/nusl-216829.

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This master´s thesis deals with organic materials for use in electronics and photonics. Attention was paid to low molecular weight materials. The theoretical part of this thesis contains brief introduction to organic electronics and photonics. In particular, organic transistors, organic solar cells and organic light-emitting diodes are mentioned. The experimental part is focused on study of electrical and optical properties of two types of phthalocyanines. Thin films and solutions of phthalocyanines were characterized by UV-VIS spectroscopy. Thin films were also characterized by current voltage characteristics, spectral response measurement of photocurrent and by method of transient photoconductivity. It was found that illumination affects the electrical properties of thin layers of phthalocyanines, the performance of the prepared thin films depends on the type phthalocyanine and also depends on the thickness of the layer.

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Schalnat, Matthew Craig. "Spectroscopic Srudies of Model Organic Photovoltaic and Organic Light Emitting Diode Organic-Organic' and Metal-Organic Heterojunctions." Diss., The University of Arizona, 2009. http://hdl.handle.net/10150/194656.

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The purpose of this Dissertation was to present fundamental approaches to expand the general knowledge of the chemistry that occurs at both the organic-organic' (O-O') and the metal-organic (M-O) interfaces in organic optoelectronic devices. In order to simplify the interactions in the initial studies presented herein, simple model molecules that represent the larger, highly conjugated molecules used in device construction were considered.UPS, reductive-desorption electrochemistry, and Raman surface spectroscopy were used to determine monolayer characteristics of thiophenol and pentafluorothiophenol on Ag. Proposed interfacial orientations and molecular spacing of the TP and F5TP were proposed. Benzene and hexafluorobenzene (F6-benzene) were then condensed and forcibly dewet onto the monolayers in an effort to understand the solid-liquid interfacial interactions. Benzene films on alkanethiol (UDT) and perfluorinated thiophenol (F5TP) were prone to rupturing, and spectroscopically appeared to be liquid-like in character, while molecular spacing of TP and adsorbed benzene on unmodified Ag template ordered benzene films. Polycrystalline films of F6-benzene forms at the interfaces of TP and unmodified substrates. F6-benzene induces a reorientation of F5TP molecules, but is subsequently unable to induce long range order. F6-benzene on UDT appears liquid-like. These studies show that fixed molecules can stimulate order or disorder at a molecular heterojunction, which may have profound effects in device efficiency.In an effort to begin to understand the complicated reaction chemistry that occurs at the organic-metal interfaces in optoelectronic devices, thin benzene films were reacted with typical device cathode metals, Ag, Mg, Al, and Ca, and studied using Raman vibrational spectroscopy. Ag and Mg form metal clusters and some adduct formation. Al undergoes an insertion reaction, forming a substituted benzene ring. Ca reacts with benzene to form a phenyl radical, which then decomposes the film into regions of ordered graphitic carbon. The results of these studies are attributed to atomic properties of the metal atoms.

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Hunter, James Freeman. "Oxidation of atmospheric organic carbon : interconnecting volatile organic compounds, intermediate-volatility organic compounds, and organic aerosol." Thesis, Massachusetts Institute of Technology, 2015. http://hdl.handle.net/1721.1/97794.

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Thesis: Ph. D. in Environmental Chemistry, Massachusetts Institute of Technology, Department of Civil and Environmental Engineering, 2015.
Cataloged from PDF version of thesis.
Includes bibliographical references (pages 101-110).
.Organic molecules have many important roles in the atmosphere, acting as climate and biogeochemical forcers, and in some cases as toxic pollutants. The lifecycle of atmospheric organic carbon is extremely complex, with reaction in multiple phases (gas, particle, aqueous) and at multiple timescales. The details of the lifecycle chemistry (especially the amount and properties of particles) have important implications for air quality, climate, and human and ecosystem health, and need to be understood better. Much of the chemical complexity and uncertainty lies in the reactions and properties of low-volatility oxidized intermediates that result from the oxidation of volatile organic precursors, and which have received comparatively little study thus far. This thesis describes three projects that link together the entire chain of oxidation (volatile to intermediate to condensed) in an effort to improve our understanding of carbon lifecycle and aerosol production. Laboratory studies of atmospherically relevant aerosol precursors show that the slow oxidation of intermediates is critical to explaining the yield and properties of aerosol under highly oxidized ("aged") conditions, and that the production of organic particles is significantly increased when intermediates are fully oxidized. This aging process is a strong function of molecular structure, and depends on aerosol concentration through the phenomenon of condensational trapping. Further laboratory studies of a series of (poly)cyclic 10 carbon alkanes show that structural effects are largely explained through fragmentation reactions, and that more generally, carbon-carbon bond scission is a ubiquitous and important reaction channel for oxidized intermediates. Finally, direct measurement of oxidized intermediate compounds in field studies shows that these compounds are abundant and important in the ambient atmosphere, with concentrations and properties in between those of volatile and particulate organic compounds. Together with other co-located measurements and complementary techniques, this enables estimates of emission, oxidation, and deposition to be constructed. The results from this thesis can be used to inform more sophisticated models of atmospheric organic carbon cycling, and to improve prediction of organic particulate matter concentrations.
by James Freeman Hunter.
Ph. D. in Environmental Chemistry

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Schuerlein, Thomas John. "Chemisorption in organic semiconductor systems: Investigation of organic semiconductor-organic semiconductor and organic semiconductor-metal interfaces." Diss., The University of Arizona, 1995. http://hdl.handle.net/10150/187068.

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The production of ordered thin films of organic monolayers is of general interest to the surface science community and of specific interest to our laboratory where the understanding of small molecule adsorption has been a long term goal. The production of ordered thin films may simplify the study of the interactions of adsorbate molecules on organic films. The production of ordered layers of aromatic hydrocarbons and dye molecules were performed under a variety of deposition conditions in an ultrahigh vacuum (UHV) environment. These films were studied with several UHV analytical techniques including low energy electron diffraction, photoelectron spectroscopies, thermal program desorption mass spectrometry and visible spectroscopy. The study of several aromatic hydrocarbons revealed that these molecules possess significant mobility on the Cu(100) surface, while adsorbing with their molecular plane parallel to the copper surface. A majority of phthalocyanine (Pc) molecules studied were observed to adsorb in a single packing structure at similar substrate temperatures for divalent metal centers and a slightly higher temperature for trivalent metal centers. Chloroaluminum phthalocyanine was determined to pack in a unique structure at 150°C and adopt the previously observed phthalocyanine structure at 175°C. It was determined that the perylene derivatives 3,4,9,10-perylenetetracarboxylic dianhydride (PTCDA) and N, N-dimethyl-3,4,9,10-perylene-bis(carboxylimide) (DMPI) dissociatively interact with a Cu(100) surface while forming an epitaxial overlayer. These two structurally similar molecules were determined to possess different growth modes at the initial stages of growth, which was attributed to their different bulk packing structures. The electronic properties of a Pc-PTCDA heterostructure were investigated via ultraviolet photoelectron spectroscopy. The investigation correctly anticipated the diode behavior of this isotype heterostructure. This study also proved the validity of the electron affinity rule, developed for inorganic structures, for organic systems.

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Bisinoti, Marcia Cristina. "Biogeoquimica aquatica do mercurio organico na Bacia do Rio Negro, Amazonia." [s.n.], 2005. http://repositorio.unicamp.br/jspui/handle/REPOSIP/249639.

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Orientador: Wilson de Figueiredo Jardim
Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Quimica
Made available in DSpace on 2018-08-04T20:31:57Z (GMT). No. of bitstreams: 1 Bisinoti_MarciaCristina_D.pdf: 1949476 bytes, checksum: a702f967a817c83e250f6e74b334ddd3 (MD5) Previous issue date: 2005
Doutorado
Quimica Analitica
Doutor em Ciências

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Rather, Elisabeth. "Supramolecular metal-organic and organic materials." [Tampa, Fla.] : University of South Florida, 2004. http://purl.fcla.edu/fcla/etd/SFE0000267.

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Mannsfeld, Stefan. "Ordering in weakly bound molecular layers: organic-inorganic and organic-organic heteroepitaxy." Doctoral thesis, Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2004. http://nbn-resolving.de/urn:nbn:de:swb:14-1098888571984-95956.

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It is an aim of this work to provide insight into the energetic influence on the ordering of molecular thin films on crystalline substrates. Here, the term substrate either refers to inorganic crystal surfaces or highly ordered layers of another organic molecular species. In order to calculate the total interface potential of extended molecular domains, a new calculation technique (GRID technique) is developed in the first part of this work. Compared to the standard approach, this method accelerates the potential calculation drastically (times 10000). The other parts of the thesis are dedicated to the comparison of experimental results (obtained by scanning tunneling microscopy and electron diffraction) to the optimal layer structure as predicted by optimization calculations. Potential calculations which are performed for the system perylenetetracarboxylicdianhydride (PTCDA) on graphite demonstrate that point-on-line coincident structures correspond to energetically favorable alignments of the molecular lattice with respect to the substrate lattice. The capability of the GRID technique to predict the optimal layer structure is demonstrated for the system peri-hexabenzocoronene (HBC) on graphite. The organic-organic heteroepitaxy system PTCDA on HBC on graphite is investigated in order to clarify to which extent the ordering mechanism there differs from that of the organic-inorganic heteroepitaxy system PTCDA on graphite. As a result of this investigation, a new type of epitaxy, i.e., substrate induced ordering is found. This new epitaxy type is governed by the inner structure of the substrate lattice unit cell. Here, the substrate surface is a layer of organic molecules itself, hence the substrate surface unit cell does indeed exhibit a complex inner structure. A generalized classification scheme for epitaxial growth incorporating this new type of epitaxy is proposed. In the last chapter, the structure of the first layers of titanylphthalocyanine (TiOPc) on Au(111) is investigated and compared to potential optimization calculations. The correspondence of experimental and theoretical results provides evidence that the GRID technique can, in principle, also be applied to molecular layers on metal surfaces
Das Ziel der vorliegenden Arbeit ist es, Einblicke in die energetischen Einflüsse, die zur Ausbildung der Schichtstruktur organischer Moleküle auf kristallinen Substraten führen, zu geben. Diese Substrate sind entweder Oberflächen anorganische Kristalle oder selbst hochgeordnete Molekülschichten. Um das totale Grenzflächenpotential ausgedehnter Moleküldomänen berechnen zu können, wird im ersten Teil der Arbeit eine neue Berechnungsmethode (GRID Technik) vorgestellt. Im Vergleich mit herkömmlichen Berechnungsmethoden auf der Basis molekülmechanischer Kraftfelder ist diese neue Methode daher um ein Vielfaches schneller (Faktor 100000). Die folgenden Teile der Arbeit sind dem Vergleich experimenteller Ergebnisse (Rastertunnelmikroskopie und Elektronenbeugung) mit, durch Potentialoptimierungsrechnungen als energetisch günstig vorhergesagten, Schichtstrukturen gewidmet. So kann für das System Perylentetracarbonsäuredianhydrid (PTCDA) auf Graphit mittels Potentialberechnungen nachgewiesen werden, daß die experimentell gefundenen ?Point-on-line koinzidenten? Strukturen energetisch günstige Anordnungen des Molekülgitters bezüglich des Substratgitters darstellen. Die Eignung der neuen Berechnungsmethode zur Vorhersage der günstigsten Adsorbatgitterstruktur für ein gegebenes System aus Molekül und Substrat, wird anhand des Systems peri-Hexabenzocoronen (HBC) auf Graphit demonstriert. Das organisch-organische Heteroepitaxiesystem PTCDA auf HBC auf Graphit wird untersucht, um zu klären, inwieweit sich die dafür gültigen Ordnungsmechanismen von denen unterscheiden, die für das Wachstum des organisch-anorganischen Heteroepitaxiesystems PTCDA auf Graphit verantwortlich sind. Dabei gelingt es, eine bisher nicht klassifizierte Art von Epitaxie, d.h. substratinduzierter Ordnung, nachzuweisen. Dieser neue Epitaxietyp ist bedingt durch die innere Struktur einer Substrateinheitszelle - das Substrat ist ja hier selbst eine Schicht geordneter Moleküle, die natürlich eine innere Struktur aufweisen. Im folgenden wird ein verallgemeinertes Klassifizierungssystem für Epitaxietypen abgeleitet, welches den neuen Epitaxietyp beinhaltet. Im letzten Kapitel wird die Struktur von der ersten Lagen von Titanylphthalocyanin (TiOPc) auf Au(111) experimentell untersucht und mit entsprechenden Potentialoptimierungsrechnungen verglichen. Die Übereinstimmung von experimentellen und theoretischen Ergebnissen zeigt, daß die GRID Technik, zumindest prinzipiell, auch für Molekülschichten auf Metallsubstraten anwendbar ist

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Blasucci, Vittoria Madonna. "Organic solvents for catalysis and organic reactions." Diss., Atlanta, Ga. : Georgia Institute of Technology, 2009. http://hdl.handle.net/1853/31723.

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Thesis (Ph.D)--Chemical Engineering, Georgia Institute of Technology, 2010.
Committee Chair: Charles Eckert; Committee Co-Chair: Charles Liotta; Committee Member: Amyn Teja; Committee Member: Christopher Jones; Committee Member: William Koros. Part of the SMARTech Electronic Thesis and Dissertation Collection.

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Oey, Ching-ching. "Organic-inorganic nanocomposites for organic optoelectronic devices." Click to view the E-thesis via HKUTO, 2005. http://sunzi.lib.hku.hk/hkuto/record/B35321222.

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Oey, Ching-ching, and 黃晶晶. "Organic-inorganic nanocomposites for organic optoelectronic devices." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2005. http://hub.hku.hk/bib/B35321222.

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Zeng, Xiaofeng. "Mechanisms for Solvolytic Elimination and Substitution Reactions Involving Short-lived Carbocation Intermediates." Doctoral thesis, Uppsala University, Organic Chemistry, 2002. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-2565.

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Solvolysis reactions of a range of tertiary substrates in largely aqueous solvents were studied in such respects as β-deuterium kinetic isotope effects, linear free energy relationships and stereochemistry.

Solvolysis of the fluorene derivatives 9-methyl–9-(2´-X-2´-propyl)fluorene (1-X, X = Cl, Br, OOCCF₃) involves a very short-lived carbocation intermediate. The fraction of alkene is increased by addition of general bases, which can be expressed by a Brφnsted parameter β = 0.07. The kinetic deuterium isotope effects vary with solvent composition in a way which is not consistent with a common carbocation intermediate which has time to choose between dehydronation and addition of a solvent water molecule.

In the absence of bases, the reaction of 4-chloro-4-(4´-nitrophenyl)pentan-2-one (2-Cl) proceeds through a short-lived carbocation intermediate yielding 4-(4´-nitrophenyl)-2-oxopent-4-ene (2-t-ne)as the main elimination product. Addition of acetate ion and other weak bases results in the base-promoted E2 (or E1cb) reaction to give (E)-4-(4´-nitrophenyl)-2-oxopent-3-ene (2-E-ne) and (Z)-4-(4´-nitrophenyl)-2-oxopent-3-ene(2-Z-ne). There is no evidence for a water-promoted E2 (or E1cb) reaction.

The stereochemistry studies of elimination from (R,S and S,R)-[1-(3´-fluoro)phenyl-2-methyl]cyclopentyl-p-nitrobenzoate (3-PNB) and its (R,R and S,S)isomer 3´-PNB and (R,S and S,R)-[1´-(3´´-fluoro)phenyl-2´-methylcyclopentyl]-2,2,2-trifluoroacetate(3-OOCCF3) exclude the concerted pericyclic elimination mechanism for formation of the alkene 1-(3´-fluoro)phenyl-2-methylcyclopentene(3-m-ne). The effects of added thiocyanate ion and halide ions on the solvolysis reaction are discussed.

Mass spectrometry analysis showed complete incorporation of the labeled oxygen from solvent water into the product 2-hydroxy-2-phenyl-3-butene (4-OH), confirming that it is the tertiary carbon-oxygen bond that is broken in the acid-catalyzed solvolysis of 2-methoxy-2-phenyl-3-butene (4-OMe). The mechanism for the dominant formation of the less stable 4-OH is discussed.

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Roth, Peter. "Asymmetric transfer hydrogenation of aromatic ketones and azirines with NH-ligands." Doctoral thesis, Uppsala University, Organic Chemistry, 2002. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-2679.

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The Ru(arene)[(1S, 3R, 4R)-3-(Hydroxymethyl)-2-azabicyclo[2.2.1]heptane catalyst was optimized as ligand in the asymmetric transfer hydrogenation of ketones and resulted in increased activity and enantioselectivity of the catalyst. Dioxolane substitution at the rear end of the amino alcohol ligand and introduction of a (R)-methyl substituent yielded a catalyst that reduced acetophenone in 96% enantiomeric excess in 90 minutes with a substrate to catalyst molar ratio of 5000. A diversity of substituted aromatic ketones was reduced with excellent rate and enantioselectivity. Based on experimental and computational results, a study of the origin of the enantioselectivity was conducted. A combination of electrostatic, steric, dispersion forces and solvation effects was suggested to be the cause of the stereo discrimination. A set of amino sulfides built upon the 2-azabicyclo and the cyclohexane structures were prepared and tested as ligands in the enantioselective transfer hydrogenation of acetophenone with [IrCl(COD)]₂ as metal precursor. With this type of catalysts, the reaction rates were good but the enantioselectivity unsatisfactory with 70% as the highest obtained enantiomeric excess. The first enantioselective reduction of aromatic 2H-azirines was accomplished by using the asymmetric transfer hydrogenation protocol. Aromatic azirines were reduced to yield chiral aziridines with up to 72% enantiomeric excess and good yields. The enantioselectivity and reactivity of the reaction were strongly influenced by substituents on the aromatic and aliphatic moiety of the substrate.

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Karimi, Farhad. "[¹¹C]Carbon Monoxide in Palladium- / Selenium-Promoted Carbonylation Reactions : Synthesis of ¹¹C-Imides, Hydrazides, Amides, Carboxylic Acids, Carboxylic Esters, Carbothioates, Ketones and Carbamoyl Compounds." Doctoral thesis, Uppsala University, Organic Chemistry, 2002. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-2931.

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[¹¹C]Carbon monoxide in low concentrations has been used in palladium- or seleniummediated carbonylation reactions such as the synthesis of ¹¹C-imides, hydrazides, amides, carboxylic acids, esters, carbothioates, ketones and carbamoyl compounds.

In these reactions aryl iodides have been used in most cases. However, less reactive aryl triflate, chloride and bromides were activated using tetrabutylammonium iodide.

The reactivities of nucleophiles may have influence on the radiochemical yield of the ¹¹Clabelled compounds. Carboxyamination of aryl halides using aniline derivatives yielded 10% of the corresponding ¹¹C-amide. However, the radiochemical yields increased significantly when the aniline derivatives were treated with lithium bis(trimethylsilyl)amide. In contrast, this reagent did not improve the radiochemical yields when primary amines such as methylamine and benzylamine were used. In these cases the radiochemical yields were improved by using pempidine.

¹¹C-Esterification usually gave low yields. However, the radiochemical yields of ¹¹C-esters could be improved by using magnesium bromide and pempidine.

An excess of ligand may have a significant impact on palladium-promoted carbonylation reaction. The radiochemical yields of ¹¹C-ketones were improved when using excess amounts of tri-o-tolylphosphine.

(¹³C)Carbon monoxide may be utilized for the synthesis of ¹³C-substituated compounds in order to confirm the position of ¹¹C-labelling.

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Karimi, Farhad. "[11C]Carbon Monoxide in Palladium- / Selenium-Promoted Carbonylation Reactions : Synthesis of 11C-Imides, Hydrazides, Amides, Carboxylic Acids, Carboxylic Esters, Carbothioates, Ketones and Carbamoyl Compounds." Doctoral thesis, Uppsala universitet, Avdelningen för organisk kemi, 2002. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-2931.

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[11C]Carbon monoxide in low concentrations has been used in palladium- or seleniummediated carbonylation reactions such as the synthesis of 11C-imides, hydrazides, amides, carboxylic acids, esters, carbothioates, ketones and carbamoyl compounds. In these reactions aryl iodides have been used in most cases. However, less reactive aryl triflate, chloride and bromides were activated using tetrabutylammonium iodide. The reactivities of nucleophiles may have influence on the radiochemical yield of the 11Clabelled compounds. Carboxyamination of aryl halides using aniline derivatives yielded 10% of the corresponding 11C-amide. However, the radiochemical yields increased significantly when the aniline derivatives were treated with lithium bis(trimethylsilyl)amide. In contrast, this reagent did not improve the radiochemical yields when primary amines such as methylamine and benzylamine were used. In these cases the radiochemical yields were improved by using pempidine. 11C-Esterification usually gave low yields. However, the radiochemical yields of 11C-esters could be improved by using magnesium bromide and pempidine. An excess of ligand may have a significant impact on palladium-promoted carbonylation reaction. The radiochemical yields of 11C-ketones were improved when using excess amounts of tri-o-tolylphosphine. (13C)Carbon monoxide may be utilized for the synthesis of 13C-substituated compounds in order to confirm the position of 11C-labelling.

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Winberg, Karl Johan. "Carborane Derivatives for Nuclide Therapy and Imaging : Synthesis and Radio-labelling." Doctoral thesis, Uppsala : Acta Universitatis Upsaliensis : Univ-bibl. [distributör], 2003. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-3561.

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Günther, Alrun Aline. "Vertical Organic Field-Effect Transistors." Doctoral thesis, Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2016. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-207731.

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Diese Arbeit stellt eine eingehende Studie des sogenannten Vertikalen Organischen Feld-Effekt-Transistors (VOFET) dar, einer neuen Transistor-Geometrie, welche dem stetig wachsenden Bereich der organischen Elektronik entspringt. Dieses neuartige Bauteil hat bereits bewiesen, dass es in der Lage ist, eine der fundamentalen Einschränkungen herkömmlicher organischer Feld-Effekt-Transistoren (OFETs) zu überwinden: Die für Schaltfrequenz und An-Strom wichtige Kanallänge des Transistors kann im VOFET stark reduziert werden, ohne dass teure und komplexe Strukturierungsmethoden genutzt werden müssen. Das genaue Funktionsprinzip des VOFET ist bisher jedoch weitgehend unerforscht. Durch den Vergleich von experimentellen Daten mit Simulationsdaten des erwarteten Bauteil-Verhaltens wird hier ein erstes, grundlegendes Verständnis des VOFETs erarbeitet. Die so gewonnenen Erkenntnisse werden im Folgenden genutzt, um bestimmte Parameter des VOFETs kontrolliert zu manipulieren. So wird beispielsweise gezeigt, dass die Morphologie des organischen Halbleiters, und damit seine Abscheidungsparameter, sowohl für die VOFET-Herstellung als auch für den Ladungsträgertransport im fertigen Bauteil eine wichtige Rolle spielen. Weiterhin wird gezeigt, dass der VOFET, genau wie der konventionelle OFET, durch das Einbringen von Kontaktdotierung deutlich verbessert werden kann. Mit Hilfe dieser Ergebnisse kann gezeigt werden, dass das Funktionsprinzip des VOFETs mit dem eines konventionellen OFETs nahezu identisch ist, wenn man von geringen Abweichungen aufgrund der unterschiedlichen Geometrien absieht. Basierend auf dieser Erkenntnis wird schließlich ein VOFET präsentiert, welcher im Inversionsmodus betrieben werden kann und so die Lücke zur konventionellen MOSFET-Technologie schließt. Dieser Inversions-VOFET stellt folglich einen vielversprechenden Ansatz für leistungsfähige organische Transistoren dar, welche als Grundbausteine für komplexe Elektronikanwendungen auf flexiblen Substraten genutzt werden können
This work represents a comprehensive study of the so-called vertical organic field-effect transistor (VOFET), a novel transistor geometry originating from the fast-growing field of organic electronics. This device has already demonstrated its potential to overcome one of the fundamental limitations met in conventional organic transistor architectures (OFETs): In the VOFET, it is possible to reduce the channel length and thus increase On-state current and switching frequency without using expensive and complex structuring methods. Yet the VOFET's operational principles are presently not understood in full detail. By simulating the expected device behaviour and correlating it with experimental findings, a basic understanding of the charge transport in VOFETs is established and this knowledge is subsequently applied in order to manipulate certain parameters and materials in the VOFET. In particular, it is found that the morphology, and thus the deposition parameters, of the organic semiconductor play an important role, both for a successful VOFET fabrication and for the charge transport in the finished device. Furthermore, it is shown that VOFETs, just like their conventional counterparts, are greatly improved by the application of contact doping. This result, in turn, is used to demonstrate that the VOFET essentially works in almost exactly the same way as a conventional OFET, with only minor changes due to the altered contact arrangement. Working from this realisation, a vertical organic transistor is developed which operates in the inversion regime, thus closing the gap to conventional MOSFET technology and providing a truly promising candidate for high-performance organic transistors as the building blocks for advanced, flexible electronics applications

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Omasta, Lukáš. "Příprava a charakterizace tenkých vrstev nízkomolekulárních materiálů pro organickou fotoniku." Master's thesis, Vysoké učení technické v Brně. Fakulta chemická, 2013. http://www.nusl.cz/ntk/nusl-216943.

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This diploma thesis is focused on characterization of properties of new organic materials with respect to its potential application in organic photonics. The theoretical part contains a themed literature research on low molecular thin films for organic photonics, mainly phthalocyanines together with description and structure of the photovoltaic energy conversion. The practical part includes the preparation of thin layers of selected organic materials for organic photonics. Prepared thin films were characterized by optical methods and current voltage characteristics. Based on these results, the thin films and structure of solar cells were optimalized. Acquired data were used to determine the materials and structures suitable for photonics applications.

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Selander, Nicklas. "Development of Multi-Component Reactions using Catalytically Generated Allyl Metal Reagents." Licentiate thesis, Stockholm University, Department of Organic Chemistry, 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-8077.

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This licentiate thesis is based on the development of catalytic reactions for the synthesis and application of organometallic reagents. By use of palladium pincer-complex catalysts, we have developed an efficient procedure for the synthesis of allylboronates starting from allylic alcohols. These reactions were further extended by including various one-pot multi-component reactions, using the in situ generated allylboronates. Furthermore, novel unsymmetrical palladium pincer-complexes were synthesized and studied in auto-tandem catalysis.

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Tilliet, Mélanie. "Synthesis and study of new oxazoline-based ligands." Doctoral thesis, KTH, Organisk kemi, 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-4858.

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This thesis deals with the study of oxazoline-based ligands in metal-catalyzed asymmetric reactions. The first part describes the synthesis of six new bifunctinal pyridine-bis(oxazoline) ligands and their applications in asymmetric metal-catalysis. These ligands, in addition to a Lewis acid coordination site, are equipped with a Lewis basic part in the 4-position of the oxazoline rings. Dual activation by means of this system was probed in cyanide addition to aldehydes. The second part is concerned with the synthesis of two pyridine-bis(oxazoline) ligands bearing bulky triazole groups in the 4-position of the oxazoline rings and a macrocyclic ligand consisting of a pyridine-bis(oxazoline) moiety and a diaza-18-crown-6 ether. The synthesis of these compounds benefits from the use of “click chemistry”. The ligands thus obtained were tested in different asymmetric catalytic reactions. Complexation studies with different bifunctional molecules that could bind into the cavity of the macrocycle were carried out using NMR spectroscopy. A third chapter is devoted to the synthesis of a supported pyridine-bis(oxazoline) catalyst and its use in catalysis. The pyridine-bis(oxazoline) ligand was efficiently connected to a polystyrene resin via a robust triazole linker. This resin could be employed in different metal-catalyzed asymmetric reactions and good results were obtained in terms of yield and enantioselectivity. Moreover, this polymer-bound ligand could be easily and efficiently recycled. Finally, the last part deals with the use of a hydroxy-containing phosphinooxazoline ligand in the hydrosilylation of imines and in the asymmetric intermolecular Heck reaction. A cationic iridium complex of this ligand was studied by NMR spectroscopy.
QC 20100914

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Oberlander, Kristin M. "CULTURES IN OPPOSITION: THE BATTLE BETWEEN CORPORATE ORGANICS AND THE ORGANIC MOVEMENT." Oxford, Ohio : Miami University, 2006. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=miami1155088707.

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Von, Sehlen Jennifer Ann. "Beyond organic defining alternatives to USDA certified organic /." CONNETC TO THIS TITLE ONLINE, 2007. http://etd.lib.umt.edu/theses/available/etd-05312007-142541/.

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Yim, Keng Hoong. "Controlling organic-organic interfaces for efficient optoelectronic devices." Thesis, University of Cambridge, 2008. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.612134.

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Sellner, Stefan. "Organic inorganic interfaces for applications in organic electronics." [S.l. : s.n.], 2006. http://nbn-resolving.de/urn:nbn:de:bsz:93-opus-25843.

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Stenta, Marco <1979&gt. "Computational models in organic and bio-organic chemistry." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2008. http://amsdottorato.unibo.it/1069/1/Tesi_Stenta_Marco.pdf.

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Stenta, Marco <1979&gt. "Computational models in organic and bio-organic chemistry." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2008. http://amsdottorato.unibo.it/1069/.

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Gardner, Lisa. "Organic Space." VCU Scholars Compass, 2007. http://hdl.handle.net/10156/1371.

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Pantoja, Plaza Katherine Milagros, Quiroz Nelitza Lesly Bartolo, Livias Jenny Claudia, and Chinguel Eliana Marisol Guerrero. "Natural Organic." Bachelor's thesis, Universidad Peruana de Ciencias Aplicadas (UPC), 2019. http://hdl.handle.net/10757/625357.

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En el presente trabajo desarrollaremos un modelo de negocio que surge debido a la necesidad que tienen hoy en día las mujeres de adquirir productos en diferentes cantidades y tamaños que le permitan disfrutar de una variedad de aromas y beneficios para su piel; debido a esto, nosotros ofreceremos productos al peso con la finalidad de que cada cliente pueda adquirir diferentes tamaños y cantidades según su necesidad. A la vez, estos productos artesanales serán elaborados con insumos naturales que certifiquen su calidad, y podrán ser encontrados en los establecimientos más concurridos de Lima. En la primera parte del presente trabajo se analizará los aspectos generales del negocio y su planeamiento estratégico en donde se realizará el análisis interno y externo; a la vez crearemos nuestra visión y misión que nos permitirá llegar a nuestro público objetivo. Además, se desarrollará las estrategias y objetivos, los cuales determinarán los pasos a seguir para el buen funcionamiento de la empresa. Para conocer la viabilidad del producto y el modelo de negocio se realizó una investigación de mercado, que permitió conocer las características de nuestro público objetivo; a la vez, conocer la oferta y demanda, para identificar la cantidad de personas que están interesadas en el producto y tipo de negocio. En el aspecto financiero detallaremos la inversión total a necesitar para la implementación del negocio, además analizaremos los estados financieros, flujo de caja e indicadores de rentabilidad, que nos permitirán conocer la rentabilidad que obtendrá el negocio. Finalmente, se realizará un análisis de riesgo y punto de equilibrio; con una proyección de cinco años.
In the present work we will develop a business model that arises because of the need of women today to purchase products in different quantities and sizes that allow you to enjoy a variety of aromas and benefits for their skin because of this we will offer products to the weight with the purpose of that each client may purchase different sizes and quantities according to your needs. At the same time, these artisanal products will be developed with natural inputs that certify their quality and may be found in the most crowded places of Lima. In the first part of this paper we will analyze the general aspects of the business and its strategic planning in where the internal and external analysis, at the same time we will create our vision and mission that will allow us to reach our target audience. In addition, develop the strategies and objectives which will determine the steps to follow for the proper functioning of the company. To learn about the viability of the product and the business model is conducted a market research which allowed to know the characteristics of our target audience; at the same time, know the supply and demand, to identify the number of people who are interested in the product and type of business. In the financial aspect we will detail the total investment needed for the implementation of the business, in addition we will analyze the financial statements, cash flow and profitability indicators, which will allow us to know the profitability you will obtain the business. Finally, will be a risk analysis and point equilibrium; with a projection for five years.
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Oyola, Carlos Harriet Penny, Perez Jill Roxana Farro, Riofrio Alejandra Alocén, Legrand María Del Carmen Luna, and Rodríguez Jonathan Francis Espinoza. "Life Organic." Bachelor's thesis, Universidad Peruana de Ciencias Aplicadas (UPC), 2018. http://hdl.handle.net/10757/624079.

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Life Organic es una propuesta de negocio con sentido ético ya que contribuye con la buena alimentación de las personas ofreciendo un portal digital móvil y web donde el target pueda obtener información transparente para adquirir alimentos orgánicos de una manera rápida, fácil y confiable; esta aplicación está dirigida para todas las personas que deseen llevar una vida saludable a través del consumo orgánico.
Life Organic is a business proposal with ethical sense given that it contributes to the good nutrition of people by offering a mobile and web digital portal where the target can obtain transparent information to acquire organic food in a fast, easy and reliable way; this application is aimed at all people who wish to lead a healthy life through organic consumption.
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Huth, Martin. "X-ray and neutron scattering study of organic-organic heterolayers for organic electronics and biointerfaces." Diss., lmu, 2010. http://nbn-resolving.de/urn:nbn:de:bvb:19-125197.

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Molodtsova, Olga. "Electronic properties of metal-organic and organic-organic interfaces studied by photoemission and photoabsorption spectroscopy." Doctoral thesis, Technische Universität Dresden, 2006. https://tud.qucosa.de/id/qucosa%3A24174.

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In this work systematic studies of the organic semiconductor CuPc have been presented. In general the investigation can be devided in three parts. In the first one we have studied the electronic structure of clean CuPc thin film. The next two parts are devoted to organic-organic and metal–organic interface formation, where one of the interface components is CuPc thin film. The main results of this thesis are: - The electronic structure of the pristine organic semiconductor CuPc (valence band and empty states) has been obtained by a combination of conventional and resonant photoemission, near-edge X-ray absorption, as well as by theoretical ab initio quantum-chemical calculations. A qualitative assignment of different VB structures has been given, or in other words the contributions of different atomic species as well as sites of the CuPc molecule to the electronic DOS has been established. In particular, it was shown, that the HOMO is mainly comprised of the spectral weights from the orbitals of carbon pyrolle atoms. Additional contributions to the HOMO stems from the benzene atoms. A combined experimental and theoretical study of the unoccupied electronic density of states of CuPc was presented. Our study allows identifying the contributions from different parts of the molecule to the unoccupied DOS and the measured spectra, which lays grounds for future studies of the evolution of the CuPc electronic states upon e.g. functionalization or doping. Application of similar studies to other organic semiconductors will also provide significant insight into their unoccupied electronic states. - The electronic properties of the organic heterointerfaces between fullerite and pristine copper phthalocyanine were studied. Both interfaces, CuPc/C60 and C60/CuPc, were found to be non-reactive with pronounced shifts of the vacuum level pointing to the formation of an interfacial dipole mainly at the CuPc side of the heterojunctions. The dipole values are close to the difference of the work functions of the two materials. Important interface parameters and hole-injection barriers were obtained. The sequence of deposition does not influence the electronic properties of the interfaces. - CuPc doped with potassium was studied by means of photoemission and photoabsorption spectroscopy. A detailed analysis of the core-level PE spectra allows one to propose possible lattice sites, which harbor the potassium ions. Contrasting to a few results reported in the literature, the films prepared in this thesis showed no finite electronic density of states at the Fermi level. - Two stages of the In/CuPc interface formation have been distinguished. The low-coverage stage is characterized by a strong diffusion of the In atoms into the organic film. Metal ions occupy sites close to the pyrolle nitrogen and strongly interact with molecules transferring negative charge to CuPc. Indium diffusion into the organic films saturates at a stoichiometry of In2CuPc. Subsequently, in the second stage the formation of a metallic indium film occurs on the top of the In2CuPc film. - Upon deposition on CuPc film Sn and Ag atoms do not diffuse into the organic film forming metallic clusters and/or thin metallic overlayer. Sharp metal-organic film interface is formed, in contrast to indium and potassium deposition. Presented experimental results also give evidence for absence of noticeable chemical reaction of Sn and Ag with CuPc thin film. - The systematic investigation of interface formation between CuPc thin film and various metals gives us the possibility to summarize all results with demonstrating similarities and differences for all systems studied.

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Molodtsova, Olga. "Electronic properties of metal-organic and organic-organic interfaces studied by photoemission and photoabsorption spectroscopy." Doctoral thesis, [S.l. : s.n.], 2007. http://nbn-resolving.de/urn:nbn:de:swb:14-1197646805493-74166.

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Du, Weiwei. "Development of new organic emissive materials for organic light-emitting diodes and organic laser applications." Electronic Thesis or Diss., Sorbonne université, 2021. http://www.theses.fr/2021SORUS215.

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Dans ce travail, de nouveaux matériaux émetteurs organiques ont été développés pour des applications dans le domaine des diodes électroluminescentes ou des lasers organiques. Tout d’abord, trois séries de molécules « through space » TADF (Fluorescence retardée activée thermiquement) à base de cœurs cyclophane ont été préparées avec succès. Leurs structures chimiques ont été caractérisées par résonnance magnétique nucléaire (RMN) et spectroscopie de masse haute résolution (HRMS). Leurs propriétés photophysiques ont été étudiées en solution et à l’état solide. Dans ces structures, le transfert de charge intramoléculaire est produit via des interactions intramoléculaires à travers l’espace entre les groupements donneur et accepteur, et leurs études ont révélé que la plupart des dérivés synthétisés présentent un caractère TADF. Les propriétés d’électroluminescence de certains dérivés ont été également étudiées en configuration OLED et des résultats prometteurs ont été mis en évidence. Ensuite, une série de molécules à gain basées sur des structures pi-conjuguées ou tridimensionnelles étendues ont été synthétisées avec succès pour des applications lasers. Leurs structures chimiques ont été caractérisées par résonnance magnétique nucléaire (RMN) et spectroscopie de masse haute résolution (HRMS). De bonnes propriétés de luminescence telles que de hauts rendements quantiques de photoluminescence (PLQY) et de courts temps de vie de fluorescence ont été démontrés en solution et à l’état solide pour la plupart des dérivés. Pour finir, ces matériaux émissifs présentent de bonnes propriétés d’émission spontanée amplifiée (ASE) avec de faibles valeurs de seuil et des dispositifs laser optiquement pompés ont également pu être fabriqués à partir de certains des dérivés de la série
In this work, new organic emitting materials were designed for the organic light-emitting diodes (OLED) or laser applications. First, three series of through-space TADF (Thermally Activated Delayed Fluorescence) molecules based on different cyclophane cores have been successfully prepared. Their chemical structures were confirmed by Nuclear Magnetic Resonance (NMR) and high-resolution mass spectrometry (HRMS). The photophysical properties were investigated in solution and solid state. In these systems, the intramolecular charge transfer was produced via intramolecular through-space interactions between the donor and acceptor units, and their study revealed that most of these derivatives exhibit a TADF character. The electroluminescence properties of some derivatives were also investigated in OLED configuration and promising results were evidenced. Second, a new set of soluble gain molecules based on extended π-conjugated or three dimensional (3D) structures have been successfully synthesized for laser applications. Their chemical structures were confirmed by Nuclear Magnetic Resonance (NMR), high-resolution mass spectrometry (HRMS) and elemental analysis. High luminescence properties such as high photoluminescence quantum yields (PLQY) and short fluorescence lifetimes were demonstrated in both solution and solid state for most of the derivatives. Finally, these emitting materials exhibits good amplified spontaneous emission (ASE) properties with low thresholds and optically pumped laser devices were fabricated based on some derivatives of the series

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Herrnsdorf, Johannes Hermann Ludwig. "Organic lasers and nanostructred organic films for hybrid integration." Thesis, University of Strathclyde, 2012. http://oleg.lib.strath.ac.uk:80/R/?func=dbin-jump-full&object_id=18568.

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Light emitting polymers (LEPs) are a promising category of organic materials for photonic applications owing to their potential for simple fabrication and availability of materials emitting across the whole visible spectrum. LEPs are already exploited commercially in the case organic light emitting diodes and their interesting properties for colour conversion and as laser gain material are under investigation. To keep the LEPs' benefit of simple and low-cost fabrication, integration onto inorganic semiconductor devices such as in particular gallium nitride light emitting diodes (LEDs) is an important research topic. In this thesis, developments towards integration of organic devices onto micro-pixellated ip-chip LEDs are presented. This particular format may be beneficial for applications such as displays, various sensing schemes and data transmission owing to spatio-temporal control, high modulation bandwidths and potential for simple integration with complementary meta l oxide semiconductor electronics. The properties of LEP films as optical gain medium were assessed on smooth and corrugated substrates. In the former case, random laser action (RL) was observed which is attributed to the high optical gain delivered by these materials. Arguments are presented suggesting that RL may be very common in high gain media. In the latter case, mechanically flexible distributed feedback lasers were fabricated in a very simple way and their properties including operational lifetime were characterised. Nano-patterned LEP films for colour conversion of LED light exhibited strong modification of the LEP emission due to the photonic crystal (PhC) effect of the periodic pattern. PhCs allow tailoring of the emission properties by appropriate design of the nano-pattern and they can be created relatively easy in organic films. Furthermore, the modulation bandwidth of an organic PhC film excited by micro-LEDs was measured to be 168 MHz and was mainly limited by the inorganicLED. This underpins the potential of LEPs for communications applications. The suitability of micro-LEDs in flip-chip format as pump source for organic semiconductor lasers was investigated. For this purpose, stripe-shaped arrays of micro-LEDs were developed that were employed for the demonstration of the first micro-LED pumped polymer laser.

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Reinheimer, Eric Wade. "Hybrid inorganic-organic, organic charge transfer, and radical based compounds with chalcofulvalene donors and organic acceptors." [College Station, Tex. : Texas A&M University, 2007. http://hdl.handle.net/1969.1/ETD-TAMU-2452.

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Dall'Ora, Lucia. "Characterization and modeling of organic solvents sorption and transport in PDMS membranes for organic/organic separations." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2017.

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This study is mainly focused on the investigation of which are the main characteristics affecting the membranes’ performances and how they are influenced by the presence of different organic solvents. Two different PDMS membranes were prepared and studied, the two materials have the same chemical structure but different number of active sites for the cross-linking process. This choice was made to investigate how the swelling of a polymer can affect membrane characteristics. The first experiment performed with these PDMS membranes was the dynamic vapor sorption of organic solvents. Both hydrocarbons and alcohols were tested in order to understand how the polymeric material interacts with the different chemical species. It is evident from the results, the higher affinity between polymer and hydrocarbons with respect to alcohols. The sorption isotherms so obtained were modelled using different theories, trying to estimate the strengths and limits of each of them. From the same sorption experiments, kinetic data for the evaluation of transport phenomena were obtained and Fick’s law was applied to calculate values of the diffusion coefficient. In the second part of this study, the same membranes were tested in presence of pure liquid organic solvents, performing some filtration experiments. Fluxes through the membranes were measured and an evaluation of rejection and Molecular Weight Cut Off were given. In the end, the membranes were tested in presence of organic solvents binary mixtures. As before, fluxes through the membranes were measured and selectivities were calculated. It was possible to observe how these membranes are not able to separate hydrocarbons but they show higher selectivity in presence of a mixture of a hydrocarbon and an alcohol. In conclusion, this research provides a guidance on which experiments can be performed to characterize a membrane material and help to understand how many different parameters can affect the separation process.

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Anderson, Michele Lynn 1968. "Characterization of organic/organic' and organic/inorganic heterojunctions and their light-absorbing and light-emitting properties." Diss., The University of Arizona, 1997. http://hdl.handle.net/10150/282555.

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Increasing the efficiency and durability of organic light-emitting diodes (OLEDs) has attracted attention recently due to their prospective wide-spread use as flat-panel displays. The performance and efficiency of OLEDs is understood to be critically dependent on the quality of the device heterojunctions, and on matching the ionization potentials (IP) and the electron affinities (EA) of the luminescent material (LM) with those of the hole (HTA) and electron (ETA) transport agents, respectively. The color and bandwidth of OLED emission color is thought to reflect the packing of the molecules in the luminescent layer. Finally, materials stability under OLED operating conditions is a significant concern. LM, HTA, and ETA thin films were grown in ultra-high vacuum using the molecular beam epitaxy technique. Thin film structure was determined in situ using reflection high energy electron diffraction (RHEED) and ex situ using UV-Vis spectroscopy. LM, HTA, and ETA occupied frontier orbitals (IP) were characterized by ultraviolet photoelectron spectroscopy (UPS), and their unoccupied frontier orbitals (EA) estimated from UV-Vis and fluorescence spectroscopies in combination with the UPS results. The stability of the molecules toward vacuum deposition was verified by compositional analysis of thin film X-ray photoelectron spectra. The stability of these materials toward redox processes was evaluated by cyclic voltammetry in nonaqueous media. Electrochemical data provide a more accurate estimation of the EA since the energetics for addition of an electron to a neutral molecule can be probed directly. The energetic barriers to charge injection into each layer of the device has been correlated to OLED turn-on voltage, indicating that these measurements may be used to screen potential combinations of materials for OLEDs. The chemical reversibility of LM voltammetry appears to limit the performance and lifetimes of solid-state OLEDs due to degradation of the organic layers. The role of oxygen as an electron trap in OLEDs has also been verified electrochemically. Finally, a more accurate determination of the offset of the occupied energy levels at the interface between two organic layers has been achieved via in situ monitoring of the UPS spectrum during heterojunction formation.

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Esfandiarfard, Keyhan. "Novel Organophosphorus Compounds for Materials and Organic Synthesis." Doctoral thesis, Uppsala universitet, Molekylär biomimetik, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-328295.

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This thesis is devoted to the development of new organophosphorus compounds for potential uses in material science and as reagents in Organic Chemistry. Organophosphorus compounds in a single molecule or organic electronics context are appealing as the phosphorous centers perturb the electronic properties of the π-conjugated systems while at the same time provide synthetic handles for subsequent synthetic modifications. As such, new synthetic methodology to such compounds and the exploration of new building blocks is of considerable interest. In a different study, novel organophosphorus compounds are synthesized and shown to promote a reaction in Organic Chemistry that has previously not been possible, i.e. the stereoselective reductive coupling of aldehydes to alkenes. Such developments enlarge the toolkit of reactions that are available to Organic Chemists, and may impact the synthetic routes to pharmaceuticals and other important commodity chemicals. A general introduction of the key structural unit of this thesis, phosphaalkenes, is given in the first chapter. The synthesis, reactivity, properties and applications of these P=C double bond containing compounds are highlighted. The Wittig reaction and its variations as well as the phosphorus analogues that produce phosphaalkenes are outlined in detail. The second chapter is dedicated to the synthesis of a precursor that is used for the preparation of novel π-conjugated, organophosphorus compounds. C,C-Dibromophosphaalkenes are prepared and the halide substituents are used for the selective introduction of acetylene units. Besides the phosphaalkenes, the successful syntheses of two new diphosphenes is presented, indicating a broad applicability of the precursors. The third chapter is dedicated to the isolation of a metal-free phosphanylphosphonate that transforms aldehydes quantitatively to their corresponding E-phosphaalkenes in a transition metal-free phospha-HWE (Horner-Wadsworth-Emmons) reaction. The reaction benefits from mild conditions, high E-stereoselectivity, and a broad substrate scope. In the last chapter, a novel method for the reductive coupling of aldehydes to olefins is introduced. The reaction, which is a vast improvement over the McMurry coupling, allows for the selective synthesis of symmetrical and most importantly unsymmetrical E-alkenes. The phosphanylphosphonate mentioned above is the reagent that facilitates the coupling of the aldehydes via a phosphaalkene intermediate. This one-pot reaction benefits from mild conditions, good conversions, and high E-stereoselectivity. In summary, the thesis presents novel aspects of organophosphorus chemistry. These include the preparations and exploration of interesting precursors for the construction of π-conjugated organophosphorus compounds, and the use of organophosphorus reagents for unprecedented transformations in Organic Chemistry.

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Santos, Vânia Aparecida de Freitas Formenton Macedo dos [UNESP]. "Aspectos metabolômico, biológico e proteômico de Maytenus ilicifolia e Salacia campestris (Celastraceae)." Universidade Estadual Paulista (UNESP), 2010. http://hdl.handle.net/11449/105821.

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Made available in DSpace on 2014-06-11T19:35:09Z (GMT). No. of bitstreams: 0 Previous issue date: 2010-08-23Bitstream added on 2014-06-13T21:07:18Z : No. of bitstreams: 1 santos_vaffm_dr_araiq.pdf: 10987404 bytes, checksum: 973eae3cf8e80c624c39ca8c1fa5c2b2 (MD5)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
Este projeto teve como principal objetivo o estudo de aspectos químicos, biológicos e biossintéticos dos metabólitos secundários de duas espécies de Celastraceae, Maytenus ilicifolia e Salacia campestris. O estudo fitoquímico das cascas das raízes das duas espécies selecionadas resultou no isolamento de oito substâncias pertencentes a três diferentes classes de metabólitos secundários, incluindo os triterpenos quinonametídeos, maitenina e pristimerina; os alcalóides piridínicos sesquiterpênicos, aquifoliunina E1, maiteina, wilforina, sendo dois inéditos, maiteinol e campestrina; além de uma catequina, ourateacatequina. Os extratos, frações e substâncias puras foram avaliados quanto a atividade antifúngica, frente aos patógenos humanos Candida albicans, C. kruseii, C. parapsilosis e Cryptococcus neoformans; tripanocida, frente a cepa Y da forma epimastigota do Trypanossoma cruzi; leishmanicida, frente a formas promastigotas de L. amazonensis e L. chagasis e antitumoral avaliado por testes de viabilidade metabólica usando três tipos de células tumorais, incluindo B16 (melanoma), HeLA (colo uterino) e U343 (astrocitoma cerebral). Em todas as matrizes biológicas avaliadas, os triterpenos quinonametídeos, maitenina e pristimerina, se mostraram os mais potentes, evidenciando atividade biológica superior aos controles positivos utilizados. Além dos triterpenos quinonametídicos, os alcalóides piridínicos sesquiterpênicos, aquifoliunina E1 e maiteinol se mostraram ativos nos testes leishmanicida e tripanocida, respectivamente, mas menos potentes que os triterpenos quinonametídeos. Experimentos para avaliar a biossíntese das etapas de oxidação que ocorrem no anel E dos triperpenos quinonametídeos foram baseados em protocolos para a extração da enzima oxidoredutase do tipo citocromo P450, supostamente envolvida nas referidas etapas de oxidação...
The project was addressed to investigate chemical, biological and biosynthetic aspects of major secondary metabolites from two Celastraceae species, Maytenus ilicifolia (espinheira-Santa) and Salacia campestris. The phytochemical study of the bark roots resulted in the isolation of eight compounds belonging to three different classes of natural products including the quinonemethides triterpenes, maytenin and pristimerin; the alkaloids pyridine sesquiterpenes, aquifoliunine E1, mayteine, wilforine, including two novel, mayteinol and campestrine; in addition to one catechin, ourateacatechin. The localization of quinonemethides triterpenes in roots of M. ilicifolia was achieved by histochemical analysis based on complexation reactions using some specific reagents to identify groups or organic functions in the interested molecule. The crude extracts, fractions and pure compounds had their antifungal properties assayed against the human pathogens Candida albicans, C. kruseii, C. parapsilosis and Cryptococcus neoformans. Additionally, their anti-parasite activity were assessed against Trypanossoma cruzi (epimastigote form of Y strain), L. amazonensis and L. chagasis (promastigote forms) while the antitumoral activity was based on metabolic viability metabolic using two kinds of tumor cells, B16 (melanoma), HeLA (uterus) e U343 (cerebral astrocytoma). The quinonemethides triterpenes, maytenin and pristimerin displayed considerable potential since were more active than controls. The alkaloids pyridine sesquiterpenes, aquifoliunine E1 and mayteinol revealed to have some potential as leishmanicidal and trypanocide, respectively, but not comparable to quinonemethides triterpenes. As the biosynthesis of quinonemethides triterpenes is concerned, the oxidation step at ring E was investigated considering the participation of cytochrome P450 oxidoreductase besides enzymatic assays using pristimerin... (Complete abstract click electronic access below)

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Modin, Judit. "Synthesis and Evaluation of Photoactive Pyridine Complexes for Electron Transfer Studies and Photoelectrochemical Applications." Doctoral thesis, Uppsala : Acta Universitatis Upsaliensis, 2005. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-6146.

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Wickremasinghe, Niranjala D. "Optical Properties of Organic Films, Multilayers and Plasmonic Metal-organic Waveguides Fabricated by Organic Molecular Beam Deposition." University of Cincinnati / OhioLINK, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1439307144.

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42

Sang, Lingzi, and Lingzi Sang. "Spectroscopy Investigation of Molecular Processes at Organic/Metal Oxide and Organic/Metal Interfaces in Organic Photovoltaic Devices." Diss., The University of Arizona, 2015. http://hdl.handle.net/10150/566987.

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The purpose of this Dissertation is to investigate the chemistry at interfaces between organic active materials and two electrodes, namely organic metal oxide cathode and metal anode, in organic photovoltaic (OPV) devices. Poor compatibility and energy level mismatch at organic/transparent metal oxide (TCO) interfaces is a long standing challenge which limits interfacial electron transfer efficiency. Phosphonic acid modifiers on TCO surfaces are able to improve interface compatibility and energy alignment. Chapters 3 and 4 in this Dissertation investigate the fundamental formation, quality and orientation of phosphonic acid monolayers on indium-doped zinc oxide (IZO) surfaces, a model TCO. Metal electrode deposition on organic active layer materials is a common last step of OPV device fabrication. Chapters 5-8 in this Dissertation explore possible molecular processes at organic-metal interfaces when metal deposition occurs under ultra-high vacuum conditions. Choosing octylphosphonic acid (OPA), F₁₃-octylphosphonic acid (F₁₃OPA), pentafluorophenyl phosphonic acid (F₅PPA), benzyl phosphonic acid (BnPA), and pentafluorobenzyl phosphonic acid (F₅BnPA) as a representative group of modifiers, Chapter 3 describes polarization modulation-infrared reflectance-absorbance spectroscopy (PM-IRRAS) of binding and molecular orientation on IZO substrates. Considerable variability in molecular orientation and binding type is observed with changes in PA functional group. OPA exhibits partially disordered alkyl chains, but on average, the chain axis is tilted 57° from the surface normal; F13OPA tilts 26° with mostly tridentate binding; the F₅PPA ring orients 72° from the surface normal with a mixture of bidentate and tridentate binding; the BnPA ring orients 59° from normal with a mixture of bidentate and tridentate binding, and the F₅BnPA ring orients 45° from normal with a majority of bidentate with some tridenate binding. These trends are consistent with what has been observed previously for the effects of fluorination on orientation of phosphonic acid modifiers. The results from PM-IRRAS are well correlated with recent results on similar systems from near-edge x-ray absorption fine structure (NEXAFS) and density functional theory (DFT) calculations. Overall, these results indicate that both surface binding geometry and intermolecular interactions play important roles in dictating orientation of PA modifiers on TCO surfaces. This work also establishes PM-IRRAS as a routine method for SAM orientation determination on complex oxide substrates. In addition to orientation studies the effect of PA deposition method on the formation of close-packed, high-quality monolayers is investigated in Chapter 4 for SAMs fabricated by solution deposition, microcontact printing, and spray coating. The solution deposition isotherm for perfluorinated benzylphosphonic acid (F₅BnPA) on IZO is studied using PM-IRRAS at room temperature as a model PA/TCO system. Fast surface adsorption occurs in the first minute; however, well-oriented high-quality SAMs are reached only after ~48 h, presumably through a continual process of molecular adsorption/desorption accompanied by molecular reorientation. Two other rapid, soak-free deposition techniques, microcontact printing and spray coating, are also explored. SAM quality is compared for deposition of phenyl phosphonic acid (PPA), F₁₃-octylphosphonic acid (F₁₃OPA), and perfluorinated benzyl phosphonic acid (F₅BnPA) by solution deposition, microcontact printing and spray coating using PM-IRRAS. In contrast to microcontact printing and spray coating techniques, 48-168 h solution depositions at both room temperature and 70 °C result in contamination- and surface etch-free close-packed monolayers with good reproducibility. SAMs fabricated by microcontact printing and spray coating are much less well ordered.Oligothiophenes are building blocks of the popular organic donor materials polythiophene and P3HT. In Chapters 6 and 7, interfacial reactions of the model thiophene-based oligomers, ɑ-sexithiophene (ɑ-6T) and 2, 2’:5’, 2”-terthiophene (ɑ-3T), with vapor deposited Ag, Al, Mg and Ca are investigated using surface Raman spectroscopy under ultra-high vacuum conditions. Results indicate that Al and Ca cause reduction of ɑ-6T to tetrahydrothiophene and calcium sulfite, respectively, with Al exhibiting less reactivity than Ca. Partial electron donation from the sulfur atom lone pair electrons to vacant Ag and Mg d or p orbitals is observed, inducing formation of polaron states at the interface. Inter-ring C-C bond rotation is also induced by this electron sharing betweenɑ-6T and both Ag and Mg. This unexpected evolution of ɑ-6T interfaces with low work function metals alters the interfacial energetics through the formation of “gap” states which ultimately impact device performance. Vapor deposited Ag forms nanoparticles on the surface and induces considerable surface enhanced Raman scattering (SERS) of the ɑ-3T along with a change in molecular symmetry and formation of Ag-S bonds; no other reaction chemistry is observed. Vapor deposited Al and Ca exhibit chemical reaction withɑ-3T spectrum initiated by metal-to-3T electron sharing. For Al, the resulting product is predominantly amorphous carbon (a-C) through initial radical formation and subsequent decomposition reactions. For Ca, the spectral evidence suggests two pathways: one leading to ɑ-3T polymerization and the other resulting in thiophene ring opening, both initiated by radical formation through Ca-to-ɑ-3T electron transfer. In Chapter 8, metal penetration depth into ɑ-3T and ɑ-6T films is investigated and compared between Ag, Al, Mg and Ca using Raman and X-ray photoelectron spectroscopies. Mg exhibits the greatest penetration with no observable surface metallization on 50 ML (15 nm) OT surfaces. Ag shows moderate penetration and metallization ability with no reaction chemistry when in contact with ɑ-6T. Al and Ca exhibit the least penetration and greatest metallization abilities, possibly due to reaction chemistry occurring between Al (or Ca) and ɑ-6T. Al and Ca both penetrate up to 10-14 nm intoɑ-6T layers. The penetration process for Ca consists of two distinct phases. Ca tends to be more evenly distributed throughout the entire ɑ-6T film and reduce the native ɑ-6T until the composition of the top 5-7 nm of the ɑ-6T film becomes constant; beyond this point, further Ca deposition penetrates and completely reduces ɑ-6T into CaS throughout the entire 10-14 nm thickness. Al atoms are more concentrated within the top 5-7 nm of the film and gradually penetrate deeper into the film. These results reveal significant but varying depths of the impact of deposited metals on OT thin films during physical vapor deposition; these results further reinforce the critical role of interfacial chemistry on organic electronic device performance.

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43

Hagberg, Daniel. "Synthesis of Organic Chromophores for Dye Sensitized Solar Cells." Licentiate thesis, Stockholm : Kemi, Kungliga Tekniska högskolan, 2007. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-4600.

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44

Kvinnesland, Thomas. "Coagulation and flocculation of dissolved organic substances with organic polymers." Doctoral thesis, Norwegian University of Science and Technology, Department of Hydraulic and Environmental Engineering, 2002. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-528.

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Coagulation of natural organic matter (NOM) in water is a well-established process, enabling or enhancing the removal of these substances by different particle separation processes. The dominating coagulating agents used are, however, inorganic salts of iron (Fe3+) and aluminium (Al3+). The primary use of organic polymers is as flocculating agents for already coagulated aggregates. However, in recent years the use of cationic organic polymers have received increasing attention as coagulating agents, used alone or in combination with the traditional metal salt coagulants.

The objective of this study was to determine how organic cationic polymers can coagulate dissolved organic substances in water. The main focus has been on how differences in chemical composition and charge density of the polyelectrolytes affect their efficiency as coagulants. This was achieved by comparing the efficiencies of low molecular weight poly- Epi-amine, polydiallyldimethylammonium chloride, cationic polyacrylamide and chitosan in jar test experiments on constructed humic water as well as on wastewater biofilm reactor effluent. In order to compare the coagulation of dissolved organic substances as such with the following flocculation of aggregates, sequential filtration through filters of decreasing pore diameters (11 µm through 0,1 µm) was chosen as the particle separation method.

All polyelectrolytes tested were efficient in coagulating NOM in humic water and reached approximately the same maximum levels of coagulation, however, different dosages were required for the different polyelectrolytes.

Results from experiments on humic water at pH 6 indicated that the difference in efficiencies of the different polyelectrolytes as coagulants for NOM are predominantly related to differences in charge density, not to differences in the chemical composition of the polymer chain. Furthermore it was shown that the effect of polyelectolyte charge density is predominantly related to the additions of different amounts of charge equivalents when dosing equal amounts of polyelectrolytes with different charge densities, not to the spatial distribution of charge as such. Experiments performed at pH 4 indicated that the effect of charge addition that was dominating at pH6 is less pronounced at pH4.

Using sequential filtration as the particle separation method showed that the coagulation of dissolved organic substances in particle free humic water by polyelectrolytes and the subsequent flocculation of aggregates are two distinguishable processes with distinguishable dosage optima. With respect to the relationship between coagulation of dissolved organic matter and flocculation in the experiments on biofilm reactor effluent, significant differences in performance were observed with chitosan relative to the synthetic polyelectrolytes. In general, the results indicated that chitosan forms aggregates with dissolved COD that more readily flocculate, internally or with other particulate matter, than the synthetic polyelectrolytes tested.

Direct comparisons of results obtained on particle free humic water and particle rich biofilm reactor effluent indicated strong similarities in the dosage response with respect to coagulation of dissolved organic substances. The presence of particles and absorption of polyelectrolyte to these did not appear to negatively affect the coagulation of dissolved organic matter with polyelectrolyte. Rather these appeared to be a positive effect of the presence of particulate matter on the polymer dose efficiency in coagulation of dissolved organic matter.

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45

Ojala, S. (Satu). "Catalytic oxidation of volatile organic compounds and malodorous organic compounds." Doctoral thesis, University of Oulu, 2005. http://urn.fi/urn:isbn:9514278704.

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Abstract This thesis describes efforts made on the development of an existing catalytic incinerator. The development work, called process characterization, consists of four general parts. These are the development of measurement methodology, the studying of construction materials, the selection of suitable catalysts and the testing of the effects of process operation conditions. The two application areas for catalytic incineration considered in this thesis are solvent emission abatement (VOC, volatile organic compounds) and chip bin emission abatement (SVOC, sulphur-containing volatile organic compounds). As a baseline, the process characterization is started with the development of measurement methodology. In general, the methodology will decrease costs and simplify the carrying out of the actual measurements and thereby make the measurement time more effective. In the methodology it is proposed that continuous total concentration measurement should be used in connection with qualitative sampling to obtain reliable measurement data. The selection of suitable construction materials for the application is very important. As shown in this thesis, the end conversions in solvent emission abatement may even be improved through the selection of the proper construction materials. In chip bin emission abatement, the problem arises from corrosive oxidation products that set limits on the construction materials used as well as on oxidation conditions. Catalyst selection is based on the following catalytic properties: activity, selectivity and durability. These catalytic properties are studied either at the laboratory or on an industrial scale. The catalytic materials tested are Pt, Pd, Pt-Pd, Cu-Mn oxides, MnO2-MgO, CuxMg(1-x)Cr2O4 and CuxCr2O4. The most important selection criteria in solvent emission abatement are proposed to be activity and selectivity. In the case of chip bin-SVOC-abatement, these are selectivity and durability. Based on these criteria, catalysts containing Cu-Mn oxides and Pt were demonstrated to be the best catalysts in VOC oxidation, and catalyst containing MnO2-MgO was shown to be best catalyst in SVOC oxidation. A study on the effect of process operation parameters (temperature, concentration and gas hourly space velocity (GHSV)) and moisture was carried out with the aid of factorial design. In VOC (n-butyl acetate) oxidation, the most influential process parameter was GHSV, which decreased the end conversion when it was increased. In SVOC (DMDS) oxidation, the effect of temperature was most significant. The end conversions increased as the temperature increased. Moisture slightly decreased the formation of by-products in n-butyl acetate oxidation. In DMDS oxidation, moisture slightly increased the end conversions at a lower temperature level (300°C). At the end of the thesis, these process parameters are also discussed from the standpoint of the catalysts' activity, selectivity and durability. Finally, proposals for process improvements are suggested.

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46

Qayyum, M. M. B. "Organic electronic materials : electroreticulated conductive polymers and potential organic superconductors." Thesis, London South Bank University, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.618648.

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47

Gorman, T. "Design and optimisation of in-organic and organic elecrooptic modulators." Thesis, University of Kent, 2010. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.516205.

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48

Bound, Michelle. "Modelling the binding of organic molecules to metal-organic frameworks." Thesis, University of Nottingham, 2018. http://eprints.nottingham.ac.uk/52440/.

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Modelling of the fundamental interactions between small organic molecule to metal-organic frameworks (MOFs) and MOF-like structures has been carried out using a variety of computational techniques to further understand and aid in the design of MOFs for gas storage and separation applications. MOFs are an emerging class of porous crystal materials made up of organic linkers and metal nodes that are being researched for many different applications including gas storage and separations. Understanding the adsorption process is vital for the future design of better adsorbents, tailored to application. There are many useful experimental techniques currently in use but the cost and complexity for many systems is great. In this thesis, the importance of computational investigations in this area is illustrated, in particular focussing on binding that occurs between MOF surfaces and gaseous molecules. A number of computational techniques are employed in this work including ab initio electron correlation and DFT calculations, looking at binding between linker like fragments and various organic molecules and classical GCMC simulation methods, used to study the uptake and binding of small gaseous molecules at, in particular, lower pressures. The different techniques used are evaluated and compared before being utilised on a variety of structures to illustrate the significance of functionalisation within organic linkers on adsorption within MOFs. Results show the importance of a combination of computational and experimental techniques to achieve the deepest understand of binding within MOFs and, to further develop and design MOFs for adsorption applications, optimum functionalisation of linkers within MOF structures is essential.

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49

Ndamyabera, Christophe Adrien. "Porous metal-organic frameworks for sorption of volatile organic compounds." Doctoral thesis, Faculty of Science, 2021. http://hdl.handle.net/11427/33877.

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Metal-organic frameworks (MOFs) present potential for various applications such as gas sorption, gas storage, sensing, drug delivery, and catalysis. This attracts researchers to design and synthesize MOFs that can respond to a specific application. In this thesis, mixed ligands 34pba and 44pba ligands (34pba = 3-(4-pyridyl)benzoate, and 44pba = 4-(4-pyridyl)benzoate) and Co2+ metal salts were used to synthesize porous MOFs {[Co(34pba)(44pba)]·DMF}n (1) and {[Co(34pba)(44pba)]·(C3H6O)}n (2), with DMF = N,N'-dimethylformamide and C3H6O = acetone through solvothermal reaction. These two relate to each other through hinge-like expansion or contraction of the guest-accessible void. The use of Zn2+ as a metal ion led to an isostructural MOFs [Zn(34pba)(44pba)]·DMF}n (3) of 1. Using 34pba as a single ligand and Cu2+ as the metal ion led to the formation of a 2D [(Cu(34pba)2]·DMF) (4) while a little variation of solvent mixture resulted in a 3D {[CuCl2(34pba)2]∙solvent}n (7) structures. The functionalized ligands 44paba and 34paba (34paba = 3-(pyridyn-4-ylmethyl)aminobenzoate, 44paba = 4-(pyridyn-4- ylmethyl)aminobenzoate) were used with Cu2+ centre to prepare [Cu(44paba)·(H2O)·(DMF)]n (5) and {[Cu3(34paba)5(H2O)2]·(DMF)2}n (6), both of which are 1D structures. The activated MOFs 1d and 3d from (1 and 2) were used for the adsorption of volatile organic compounds (VOCs) and gases. In all tested guest molecules, there was higher sorption capacity in 1d which could be attributed to some gate opening process occurring which does not occur in 3d. Some effects responding to the sorption such as the change of colour in 1d were characterized. This colour change may be associated with the d-d, metal to ligand charge transfer, or π to π* transitions in coordination complex. Crystal structures and their stability, sorption properties and selectivity were characterized by single crystal X-ray diffraction, thermogravimetric analysis, differential scanning, hot stage microscopy, powder X-ray diffraction, infrared spectroscopy, and proton viii nuclear magnetic resonance (1H NMR) analysis. This thesis also reports the effect of methanol on discrete complexes of cis-dichloro-bis(ethylenediamine)cobalt(III) chloride (Coen) that led to the formation of a new crystal structure upon the removal of the water of hydration. The lattice energies calculated prove that Coen is more stable to allow a quick reversible sorption.

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Kao, Chi-Yueh. "Thin films of organic-based magnetic semiconductors for organic spintronics." The Ohio State University, 2012. http://rave.ohiolink.edu/etdc/view?acc_num=osu1343748166.

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Dissertations / Theses on the topic 'Organic'

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