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Surface Modification of Fluorine-Doped Tin Oxide Thin Films Using Femtosecond Direct Laser Interference Patterning: A Study of the Optoelectronic PerformanceHeffner, Herman, Soldera, Marcos, Ränke, Fabian, Lasagni, Andrés Fabián 10 January 2025 (has links)
Transparent conductive oxides (TCOs) are used in solar cells not only to extract photogenerated carriers but also to allow sunlight to reach the photoactive material. Therefore, controlling the electrical and optical properties of such oxides is crucial for the optimization of the efficiency of solar cells. Herein, direct laser interference patterning (DLIP) method is used to control the surface morphology, optical and electrical properties of fluorine-doped tin oxide (FTO) by applying femtosecond laser pulses. The topography characterization reveals periodic line-like microstructures with a period of 3.0 μm and average heights between 20 and 185 nm, depending on the applied laser fluence levels. Laser-induced periodic surface structures are observed on the valleys of the texture aligned perpendicularly to the laser radiation polarization. A relative increase in the average total and diffuse optical transmittance up to 5% and 500%, respectively, is obtained in the 400–800 nm spectral range as a consequence of the generated micro- and nanostructures. Calculations of two figures of merit suggest that the texturing of FTO might enhance the efficiency of solar cells, in particular dye-sensitized (DSSCs). The findings of this study confirm that DLIP is a convenient technique for structuring electrodes for highly efficient optoelectronic devices.
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Influence of Fluence and Pulse Number on Laser Cleaning of Atmospheric-Pressure-Plasma-Jet-Etched Optical GlassesHeinke, Robert, Arnold, Thomas, Ehrhardt, Martin, Lorenz, Pierre, Zimmer, Klaus 17 January 2025 (has links)
The use of beam-based technologies to process optical elements with nanoscale precision enables the fabrication of freeform surfaces. Especially, atmospheric pressure plasma jets (APPJ) have desirable properties such as atmospheric pressure machining, dry processing, and direct writing capabilities. However, the presence of metal oxides in optical glasses leads to the formation of nonvolatile reaction products during APPJ etching with fluorine-containing gas mixtures, forming a residual layer that increases surface roughness and alters etching behavior. To prevent the formation of the residual layer, the APPJ process is combined with laser cleaning. For a possible future in situ cleaning of the residual layer during the plasma process, laser parameter ranges need to be found to remove the residual layer without damaging the glass surface. Therefore, planar etchings are performed by APPJ on N-BK7 and Zerodur and the etched planes are subsequently laser irradiated with varying pulse numbers and fluences. The processed samples are then examined by scanning electron microscopy. For both N-BK7 and Zerodur, a parameter range is identified that results in clean surfaces. The best machining results are achieved with 2–16 pulses and laser fluences of 0.6–1.2 J cm−2 for N-BK7 and 0.56–0.7 J cm−2 for Zerodur.
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Mechanochemical Synthesis of low F-Doped Aluminium Hydroxide FluoridesScalise, Valentina 21 January 2019 (has links)
Die Mechanochemie ist eine effekive und überzeugende Methode zur Herstellung von Alumniumhydroxidfluoriden (Al(OH)3-xFx) mit einem sehr geringen Fluorgehalt. Durch den Prozess des Mahlens werden strukturelle Defekte in den Kristalliten erzeugt, die zu einer zunehmenden Amorphisierung des Kristallsystems führen. Die partielle Fluorierung von Alumniumhydroxid während des Mahlprozesses führt dabei zu einer noch stärkeren Amorphisierung und zur Bildung von Alumniumhydroxyfluoriden. Eine wichtige Rolle bei der resultierenden Produktzusammensetzung spielt die Variation der Synthesebedingungen, wie der Grad der Fluorierung, der Dauer des Mahlprozesses und des Wassergehalt der Edukte.
Folglich wurde zuerst der Einfluss von Wasser und dessen Bedeutung durch die verschiedenen Kombinationen von Oxid- und Hydroxid- (Al(OH)3, Al2O3), sowie Fluorid-Quellen mit oder ohne Kristallwasser (β-AlF3.3H2O, α-AlF3) bei der mechanochemischen Synthese von hochgestörten Alumniumhydroxidfluoriden untersucht.
Um den optimalen Fluorierungsgrad zu ermitteln, wurden verschiedene Aluminiumhydroxidfluoride mit Al/F-Molverhältnissen von 1:1.5 bis 1:0.05 über die mechanochemische Syntheseroute hergestellt. Eine tiefergehende Charakterisierung der Struktur- und Oberflächeneigenschaften der entsprechenden Produkte erfolgte mittels XRD, 27Al- und 19F-Festkörper-NMR, thermischer Analyse, Stickstoffabsorptions- und Zeta Potentialmessungen. Mit γ-Al(OH)3 und β-AlF3•3H2O als Hydroxid- und Fluorid-Quellen wurden dabei ab einem Verhältnis Al:F von 1:0.25 und hin zu höheren Fluoridanteilen besonders ungeordnete Strukturen erzeugt. Der Fluorierungsgrad betrifft dabei besonders die Ausbildung von 4- und 5-fach koordinierten Al-Zentren, die sonst nicht in den Edukten vorkommen. Diese Spezies beeinflussen die Bildung von Alumniumoxid und ermöglichen den Phasenübergang zu α-Al2O3 schon bei tieferen Temperaturen.
Der Einfluss der Mahldauer auf die Struktur und Oberfläche wurde am Beispiel von γ-Al2O3 im Detail untersucht. Die mechanochemische Synthese beeinflusst dabei die Absorption von Fluor an der Grenzschicht von γ-Al2O3 zu Wasser stark. Die Dauer des Mahlprozesses gewinnt daher einen großen Einfluss auf die entstehenden Produkte. Da Fluor nicht im Bulk von γ-Al2O3 vorkommt, kann mit der 19F-Festkörper-NMR eine Zuordnung der unterschiedlichen an der Oberfläche adsorbierten F-Spezies getroffen werden. / The mechanochemical approach opens a reliable and effective strategy for the formation of aluminium hydroxide fluorides with a very low F-content. Milling has the effect of introducing structural defects, causing amorphisation. The fluorination by milling creates a further and drastic increase of this degree of amorphisation.
Synthesis conditions (milling time, fluorination degree, water content) play a crucial role in the product composition.
Firstly, the significant role played by water in the mechanochemical synthesis of highly distorted aluminium hydroxide fluorides was evaluated. The importance of water in the synthesis was considered by a separated combination of O/OH sources (Al(OH)3, Al2O3) and fluorine sources with or without structural water (β-AlF3.3H2O, α-AlF3).
Concerning the degree of fluorination, different aluminium hydroxide fluorides with varying Al/F molar ratios from 1:1.5 up to 1:0.05 were successfully synthesized by mechanochemical reactions. The characterization of the products by XRD, 27Al and 19F MAS NMR, thermal analysis, nitrogen adsorption and zeta potential techniques allows a detailed understanding of the structure and surface properties of the products. Using γ-Al(OH)3 and β-AlF3•3H2O as OH- and F-sources, respectively, strongly disordered products were obtained with an Al: F molar ratio higher than 1:0.25. The degree of fluorination affects the amount of 4- and 5-fold coordinated Al sites, not present in the reactants. Obviously, these species affect the phase transition to alumina, by decreasing the transition temperature of the formation of α-Al2O3.
The influence of the milling time was considered by studying the power of a high energy ball milling process on the structure and at the surface of γ-Al2O3. The mechanochemical treatment strongly influences the adsorption of fluorine at the γ-Al2O3/ water interface. The time of the treatment has relevant importance on these processes. Since fluorine is not originally present in the bulk of γ-Al2O3, 19F MAS NMR studies allow the discrimination of different F-species adsorbed at the surface or present as metal fluoride particles in γ-Al2O3 powders after adsorption experiments.
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Optical Enhancement of Fluorine-Doped Tin Oxide Thin Films using Infrared Picosecond Direct Laser Interference PatterningHeffner, Herman, Soldera, Marcos, Lasagni, Andrés Fabián 16 May 2024 (has links)
Surface texturization of Transparent Conductive Oxides (TCOs) is a well-known strategy to enhance the light-trapping capabilities of thin-film solar cells and thus, to increase their power conversion efficiency. Herein, the surface modification of fluorine-doped tin oxide (FTO) using picosecond infrared direct laser interference patterning (DLIP) is presented. The surface characterization exhibits periodic microchannels, which act as diffraction gratings yielding an increase in the average diffuse transmittance up to 870% in the spectral range of 400–1000 nm. Despite the one dimensionality of the microstructures, the films did not acquire a significant anisotropic electrical behavior, but a partial deterioration of their conductivity is observed as a result of the removal of conductive material. This work proposes the feasibility of trading off a portion of the electrical conductivity to obtain a substantial improvement in the optical performance.
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Development and comparison of analytical methods for the determination of PFASs as sum parameters in environmental samples using HR-CS-GFMASSimon, Michael Fabian 28 February 2024 (has links)
Im ersten Teil wurde Probenvorbereitungs-Methoden und instrumentelle Methoden zur Organofluor-Bestimmung verglichen, um Vor- und Nachteile bei der Summenparameter-Analytik von per- und polyfluorierten Alkylverbindungen (PFAS) zu identifizieren. Daher wurden Oberflächenwasserproben aus der Spree in Berlin und Industrieabwasserproben mit zwei PFAS-Summenparametern analysiert – dem extrahierbaren (EOF) und dem adsorbierbaren organisch gebundenen Fluor (AOF). Beide PFAS-Summenparameter wurden mit zwei fluorsensitiven Detektionssystemen analysiert – Hochauflösender Kontinuumstrahler-Graphitofen Molekülabsorptionsspektrometrie (HR-CS-GFMAS) und combustion Ionenchromatographie (CIC). HR-CS-GFMAS erwies sich im Vergleich zu CIC als der empfindlichere und schnellere Ansatz mit höherer Präzision.
Im zweiten Teil wurde eine neue Methode zur PFAS-Summenparameteranalyse und EOF-Bestimmung in Bodenproben auf Basis von HR-CS-GFMAS entwickelt und optimiert. EOF-Massenanteile wurden bei mehrfacher Extraktion und Nutzung der Festphasenextraktion (SPE) zur Entfernung anorganischen Fluors untersucht. Bei einem Vergleich der optimierten Methode mit und ohne SPE zeigte sich eine drastische Diskriminierung von Organofluor-Verbindungen mittels SPE.
Im dritten Teil wurden Organofluor-Massenbilanzen in aquatischen Systemen anhand von Oberflächenwasser- und Schwebstoffproben (SPM) untersucht. SPM-Proben wurden mit vier komplementären Analysemethoden analysiert – target und non-target, direct total oxidizable precursor assay (dTOPA) und EOF. Daher wurden drei Organofluor-Massenbilanzansätze für die räumlich und zeitaufgelöste SPM-Probenanalyse verwendet: (I) Identifizierung von oxidierbaren PFAS-Vorläufer, (II) Identifizierung des Anteils der identifizierten und nicht identifiziertes EOF und (III) PFAS-target, PFAS dTOPA, non-target-Screening und EOF-Analyse, um das nicht identifizierte EOF aus Ansatz (II) weiter zu entschlüsseln. / In the first part, a comparison of sample preparation and instrumental methods for organofluorine determination was used to identify advantages and disadvantages in sum parameter analysis of per- and polyfluoroalkyl substances (PFASs). Therefore, surface water samples from the Spree River in Berlin, Germany and industrial effluent samples were analyzed using two PFAS sum parameters – the extractable (EOF) and adsorbable organically bound fluorine (AOF). Both PFAS sum parameters were analyzed using two fluorine sensitive detection systems – high-resolution-continuum source-graphite furnace molecular absorption spectrometry (HR-CS-GFMAS) and combustion ion chromatography (CIC). HR-CS-GFMAS turned out to be the more sensitive and faster approach accompanied with higher precision compared to CIC.
In the second part, a new method for PFAS sum parameter analysis and EOF determination in soil samples based on HR-CS-GFMAS was developed and optimized. EOF mass fractions were investigated upon multiple extraction and utilization of solid phase extraction (SPE) for inorganic fluorine removal. In a comparison of the optimized method with and without SPE, a highly biased discrimination of organofluorines using SPE was shown.
In the third part, organofluorine mass balances were investigated in aquatic systems using surface water and suspended particulate matter (SPM) samples. SPM samples were analyzed using 4 complementary analytical methods – target and non-target HRMS, direct total oxidizable precursor assay (dTOPA) and EOF. Therefore, 3 organofluorine mass balance approaches were used for SPM sample analysis in spatial and time resolved manner: (I) Identification of oxidizable PFAS precursors, (II) Identification of the proportion of identified and unidentified EOF and (III) PFAS target, PFAS dTOPA, non-target screening and EOF analysis to further unravel the unidentified EOF from approach (II).
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Stereospecific dehydroxyfluorination and the synthesis of trifluoro D-hexose sugar analoguesBresciani, Stefano January 2011 (has links)
This thesis describes stereospecific fluorination reactions, and addresses the synthesis of fluorosugars. In Chapter 1, the influence of fluorine on the physical properties of organic molecules, as well as its stereoelectronic effects, are introduced. Furthermore, an overview of nucleophilic and electrophilic fluorination reactions is given. Chapter 2 describes the dehydroxyfluorination of allylic alcohol diastereoisomers 155a and 155b, which can proceed either by direct or allylic fluorination. The regio- and stereo- selectivities were also assessed. Chapter 3 outlines the synthesis of the novel trifluoro D-glucose analogue 193 and trifluoro D-altrose analogue 216. The transport of these hexose analogues across the red blood cell membranes was then explored, to investigate the influence of polarity versus hydrogen bonding ability in carbohydrate-protein interactions. Chapter 4 describes the development and optimisation of Bio’s methodology, to promote stereospecific dehydroxyfluorination of benzylic alcohols (R)-213 and (R)-227 by addition of TMS-amine additives 226 and 229. And finally Chapter 5 reports the experimental procedures as well as the characterisation and the crystallographic data of the molecules prepared in this thesis.
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Fluorine and chlorine fractionation in the sub-arc mantle : an experimental investigation / Fractionemment du fluor et du chlore dans le manteau sub-arc : une approche expérimentaleDalou, Célia 21 January 2011 (has links)
Les éléments volatils libérés de la plaque plongeante lors de la subduction jouent un rôle fondamental durant la formation des magmas d'arc dans le coin mantellique. Depuis quelques années, les développements des techniques d'analyse par sonde ionique ont permis l'analyse de ces éléments, en particulier F et Cl, dans les magmas d'arc, et notamment dans les magmas d'arc primaires grâce aux avancées des études sur les inclusions magmatiques. Une récente étude des inclusions magmatiques du Mont Shasta (E. U.) (Le Voyer et al., 2010) a montré que le fractionnement du F et du Cl apportait des informations sur la genèse des magmas d'arc. Afin de caractériser la source de ces magmas, j'ai étudié les coefficients de partage du fluor et du chlore. Dans cette étude, je présente les premiers coefficients de partage du F et du Cl, entre des liquides de fusions silicatés anhydres et hydratés et des minéraux mantelliques tels que olivine, orthopyroxène, clinopyroxène, plagioclase, grenat ainsi que pargasite et phlogopite. Les valeurs sont issues de 300 mesures dans 24 expériences de fusion, réalisées entre 8 et 25 kbars et, 1180 et 1430˚C. Les faibles concentrations en F et Cl dans les minéraux ont été analysées par la sonde ionique Cameca IMF 1280 de WHOI en utilisant le mode d'ions secondaires négatifs. Les résultats montrent que DOpx/meltF varient de 0.123 à 0.021 et DCpx/meltF de 0.153 à 0.083, tandis que DOpx/meltCl varient de 0.002 à 0.069 et DCpx/meltCl de 0.008 à 0.015. De plus, DOl/meltF de 0.116 à 0.005 et DOl/meltCl de 0.001 à 0.004 ; DGrt/meltF de 0.012 à 0.166 et DGrt/meltCl de 0.003 à 0.087 avec l'augmentation de la teneur en eau et la diminution de la température dans les expériences. Je montre aussi que le F est compatible dans la phlogopite (DPhl/meltF >1.2) alors qu'il est incompatible dans la pargasite (DAmp/meltF de 0.36 à 0.63). A l'inverse, Cl est plus incompatible dans la phlogopite (DPhl/meltCl en moyenne 0.09±0.02), que dans la pargasite (DAmp/meltCl de 0.12 à 0.38). Cette étude démontre que F et Cl sont substitués dans des sites spécifiques de l'oxygène, ce qui les rend plus sensibles que les éléments traces aux variations de chimie des cristaux et de la quantité d'eau, et donc aux conditions de fusion. En utilisant ces nouveaux coefficients de partage, j'ai modélisé la fusion de lithologies potentielles du manteau sub-arc permettant de 1) déterminer la quantité de fluide aqueux impliqué dans la fusion, 2) distinguer la fusion induite par apport de fluides de la fusion d'une source à minéraux hydratés et 3) la fusion d'une lithologie à pargasite de celle à phlogopite, et montre que la source de certains magmas primaires d'arc, par exemple d'Italie, contient de la pargasite et de la phlogopite, tandis d'autres magmas primaires d'arc résultent d'une fusion par apport de fluides. / Volatile elements released from the subducting slab play a fundamental role during the formation of arc magmas in the mantle wedge. Advances of melt inclusion studies enlarged the data on volatile abundance in arc magmas, and it is now possible to characterize some volatile contents in arc primary magmas, in particular F and Cl. A recent study of Mt Shasta melt inclusions (LeVoyer et al., 2010) shows that fractionation of F and Cl potentially contains information about arc magma genesis. In order to trace the source of arc magmas, fluorine and chlorine partitioning was investigated. Here, I present new experimental determinations of Cl and F partition coefficients between dry and hydrous silicate melts and mantle minerals: olivine, orthopyroxene, clinopyroxene, plagioclase, garnet and also pargasite and phlogopite. The values were compiled from more than 300 measurements in 24 melting experiments, conducted between 8 and 25 kbars and between 1180 and 1430˚C. The low abundance F, Cl measurements in minerals were done by Cameca IMF 1280 at WHOI using the negative secondary ion mode. The results show that DOpx/meltF ranges from 0.123 to 0.021 and DCpx/meltF ranges from 0.153 to 0.083, while Cl partition coefficient varies from DOpx/meltCl from 0.002 to 0.069 and DCpx/meltCfrom 0.008 to 0.015, as well. Furthermore, DOl/meltF ranges from 0.116 to 0.005 and DOl/meltCl from 0.001 to 0.004; DGrt/meltF ranges from 0.012 to 0.166 and DGrt/meltCl from 0.003 to 0.087 with the increasing water amount and decreasing temperature. I also show that F is compatible in phlogopite DPhl/meltF > 1.2) while DAmp/meltF is incompatible in pargasite DAmp/meltF from 0.36 to 0.63). On the contrary, Cl is more incompatible in phlogopite (DPhl/meltCl > 1.2 on average 0.09 ± 0.02), than in pargasite (DPhl/meltCl from 0.12 to 0.38). This study demonstrates that F and Cl are substituted in specific oxygen site in minerals that lead then to be more sensitive than trace elements to crystal chemistry and water amount variations thus melting conditions. Using those new partition coefficients, I modelled melting of potential sub-arc lithologies with variable quantity aqueous-fluid. This model is able to decipher 1) amount of aqueous-fluid involved in melting, 2) melting induced by fluid or melting of an hydrous mineral-bearing source and 3) melting of either pargasite-bearing lithology or phlogopite-bearing lithology and shows that sources of some primitive melts, for instance from Italy, bear pargasite and phlogopite, while some primitve melts seem to be the results of fluid-induced melts.
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Apport de la chimie ‘‘click’’ pour le marquage au carbone-11 et au fluor-18 de nucléosides et d’oligonucléotides / "Click" chemistry contribution for labeling nucleosides and oligonucleotides with carbon-11 and fluorine-18 as potential radiotracers for Positron Emission Tomography (PET) imagingBordenave, Thomas 14 December 2012 (has links)
La Tomographie par émission de positons (TEP) constitue l’une des techniques d’imagerie médicale les plus novatrices pour la visualisation in vivo des processus biologiques. Elle intervient comme technique de choix pour le diagnostic dans de nombreux domaines notamment, en oncologie, cardiologie ou encore en neurologie. La conception et l’élaboration de nouveaux radiotraceurs sont en perpétuel développement. L’utilisationd’oligonucléotides (ODN) modifiés (aptamères) possédant une grande affinité et spécificité pour une cible (gène,protéine, principe actif), comme radiotraceur pour l’imagerie in vivo apparait comme une alternative intéressante. A ce jour, quelques rares exemples d’oligonucléotides marqués, par un radioisotope, ont été décrits dans la littérature.Dans ce contexte, il a été développé deux méthodologies d’introduction du radioisotope (11C ou 18F) en dernièreétape de synthèse par chimie ‘‘click’’ pour le marquage de nucléosides et d’oligonucléotides envisagés commeradiotraceurs pour la TEP. / Positron Emission Tomography (PET) is a powerful molecular-imaging technique for physiological and biologicalinvestigations in various areas, such as oncology, cardiology, and neurosciences, as well as for drug development.Due to the increasing need of this technique for in vivo applications, there is always a demand for the developmentof new tracers and radiolabeling strategies. Furthermore, because of their excellent targeting capacities and easysynthesis along with a high level of diversity, oligonucleotides are already extensively used in vitro as ligands fornucleic acids (antisense oligonucleotides), proteins, and small related molecules (aptamer oligonucleotides). Theuse of aptamers for in vivo imaging appears especially promising, because of the wide range of possibilitiesavailable to introduce variations in their structure through defined chemical modifications. However, only fewexamples of oligonucleotide labeling for PET have been reported. In this context, we have developed twomethodological ways to introduce the radioisotope (11C, 18F), by ‘‘click’’ chemistry, at the last radiosynthesis stepin order to label nucleoside and oligonucleotide as potential radiotracers for PET.
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Design, synthesis and biological evaluation of new platelet aggregation inhibitors and novel methodologies for the preparation of CF₂R containing molecules / Synthèse et évaluation biologique de nouveaux inhibiteurs de l'agrégation plaquettaire et nouvelles méthodologies pour la préparation de molécules contenant des motifs CF₂RKhalaf, Ali 21 February 2013 (has links)
Dans la première partie nous décrivons la synthèse et l'évaluation biologique de nouveaux inhibiteurs de l'agrégation plaquettaire, composés dont la structure a été établie en partant du 12-HETE et du 13-HODE. Dans la seconde partie nous développons de nouvelles méthodologies pour la préparation de molécules contenant des motifs CF₂R. Tout d'abord une stratégie très flexible a été mise au point pour la préparation de composés gem-difluorobisaryliques et de leurs analogues hétéroaromatiques. Elle est basée sur l'emploi d'intermédiaires gem-difluoropropargyliques faciles d'accès. Par une séquence de Diels-alder-aromatisation on obtient les molécules cibles de la première série. Pour la seconde, des réactions de cycloaddition dipolaire 1,3 ont été utilisées. A partir de ces intermédiaires, des chimiothèques ciblées de molécules fluorées ont été préparées. Nous nous sommes intéressés ensuite à la synthèse de composés fluorés fonctionnalisés et chiraux à travers des réactions d'organocatalyse asymétrique. A partir d'énals gem-difluorés des réactions de Diels-Alder et des additions 1,4 asymétriques ont été réalisées avec succès. / The first part of the thesis deals with the synthesis and biological evaluation of new platelets aggregation inhibitors, based on 12-HETE, 13-HODE and their analogues. In the second part we are interested in novel methodologies for the preparation of CF₂-containing molecules : First, a flexible strategy for the synthesis of gem-difluoro-bisarylic derivatives and heteroaromatic analogues was designed based on the easy synthesis and the reactivity of gem-difluoro propargylic intermediates, which by Diels-Alder cycloaddition and 1,3-dipolar cycloadditions afforded respectively the bisarylic and mixed arylic heteroarylic scaffolds. In addition, two small libraries were constructed around a bisarylic scaffold as representative examples. Second, we were interested in the synthesis of optically active functionalized molecules containing a gem-difluoro group, using asymmetric organocatalysis protocols. After preparation of the gem-difluoro enals, from their difluoropropargylic precursors, asymmetric organocalytic Diels-Alder cycloaddition and 1,4-conjugated additions were successfully performed.
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Desempenho de bovinos nelore suplementados com fontes alternativas de fósforo /Lemos, Guilherme Cazerta. January 2006 (has links)
Orientador: Manoel Garcia Neto / Banca: Cecílio Viega Soares Filho / Banca: Júlio César Damasceno / Resumo: Foi avaliado o desempenho produtivo e a interferência do flúor em bovinos Nelore suplementados com fontes alternativas de fósforo. As fontes de fósforo e as relações P:F foram distribuídas nos seguintes tratamentos: controle (CONTNEG), fosfato bicálcico 120:1 (FB-120), 30:1 (FB-30) e 10:1 (FB-10), monobicálcico 60:1 (MBC-60), superfosfato triplo 30:1 (SFT-30) e rocha de Cajati 10:1 (ROCHA-10). Foram utilizados 49 novilhos, desmamados, com nove meses de idade, castrados e com 230 kg de peso médio, distribuídos em sete piquetes, com água e mistura mineral completa ad libitum, exceto fósforo. A dieta padrão foi calculada para um ganho de peso aproximado de 0,500 kg/dia. Os animais do tratamento SFT-30, atingiram o peso de 520 kg, aproximadamente cinco meses antes que os do tratamento ROCHA-10, devido à solubilidade do P nas fontes. As análises de fósforo no osso mostraram diferença estatística apenas entre o tratamento CONTNEG e os tratamentos com fosfato bicálcico. As análises de flúor no osso se mostraram intimamente associados à quantidade de flúor disponível nas fontes testes. Pode-se concluir que as diferentes fontes de fósforo utilizadas interferiram nos resultados de desempenho dos animais. / Abstract: The productive performance and the interference of fluorine in supplemented Nelore bovines with alternative sources of phosphorus were evaluated. The sources of phosphorus and relations P:F had been distributed in the following treatments: control (CONTNEG), dicalcium phospate 120:1 (FB-120), 30:1 (FB-30) and 10:1 (FB-10), monodicalcium 60:1 (MBC-60), triple superphosphate 30:1 (SFT-30) and Cajati Rock 10:1 (ROCHA-10). Forty nine castrated steers with nine months of age averaging 230 kg distributed in seven pens, with water available and a complete mineral mixture, except phosphorus. The ration was formulated for a weight gain of 0,500 kg/day. Animals of SFT-30 treatment had reached 520 kg approximately five months before ROCHA-10 treatment, due to the P solubility in the sources. The analyses of phosphorus in the bone had shown statistical differences only between treatment CONTNEG and the treatments with dicalcium phosphate. Bone fluorine analyses were highly associated to fluorine quantity in the phosphorous sources evaluated. It can be concluded that the different phosphorus sources used had influenced animal performance. / Mestre
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