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McNichols, Brett William. "Synthesis and Application of Styryl Phosphonic and Cinnamic Acid Derivatives." Thesis, Colorado School of Mines, 2017. http://pqdtopen.proquest.com/#viewpdf?dispub=10624231.
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Styryl phosphonic and cinnamic acid derivatives have been gaining attention as key candidates to modulate specific electrode properties in organic electronic devices such as work function, surface energies, wettability, and electron charge transfer kinetics that lead to increased efficiency, operational range, and device lifetimes. Very few of these acids are commercially available. The driving factor behind this research is to explore simple, high yield, and inexpensive synthetic routes towards synthesis of these acids. Herein, the novel synthesis of vinyl phosphonic acids (VPAs) and their subsequent influence on interface properties compared to their phenyl phosphonic acids (PPAs) and benzyl phosphonic acids (BPAs) analogues are explored. This includes an in depth comparison of varying polar VPA, BPA, and PPA “families” attachment on conductive oxides as they allow for careful work function tuning of band edge energy and chemical properties on these surfaces.
By leveraging similar techniques of VPA synthesis we can produce analogous cinnamic acids in which these same surface control concepts are applied on the surface of lead sulfide (PbS) colloidal semiconductor nano-crystals, or quantum dots (QDs). In order to do this, first a development of a simple solution-phase ligand exchange was necessary, from which we selectively replace native solubilizing ligands with these fictionalized cinnamic acids. This application achieved remarkable control allowing the band edge position to be tuned over an unprecedented 2.0 eV.
This cinnamic acid synthetic chemistry can then be extended to functionalize multi acrylate containing molecules creating organic linkers to be integrated into Metal Organic Frameworks (MOFs). MOFs have increasingly gained attention for many high impact applications including but not limited to catalysis, gas storage and release, sensors, energy harvesting, conductivity, and filtration. A great amount of research is presently being conducted in developing new MOFs from the same handful of commercially available linkers. We introduce synthetic techniques for 18 isoreticular series of linkers that can be formulated with similar, if not identical, conditions giving way to the formation of previously unknown frameworks. This technique led us to incorporate a number of these linkers into Ni-MOFs and investigate catalytic activity for conversion of oleic acid to liquid hydrocarbons.
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Oquendo, Galarza Luis E. "Modification of Indium Tin Oxide Surfaces with Phosphonic Acid Functionalized Phthalocyanines." Diss., The University of Arizona, 2014. http://hdl.handle.net/10150/344225.
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The overall efficiency of organic photovoltaics cells (OPVs) is influenced by the nature of the charge injection barrier at the transparent conducting oxide (TCO) bottom contact. Modification of the transparent conducting oxide (TCO)/organic interface with an electroactive molecular monolayer will potentially create a robust ohmic contact that will influence the efficiency of hole injection into the TCO. Asymmetric zinc Phthalocyanines (ZnPc) with a flexible phosphonic acid (PA) linker have been synthesized and used to modify indium tin oxide (ITO) surfaces. The adsorption of PA functionalized asymmetric ZnPcs on an ITO/waveguide was monitored using attenuated total reflectance (ATR) spectroscopy. Polarized dependent ATR spectroscopy was used to determine the orientation of these absorbed subpopulations species on ITO modified surfaces as a function of wavelength using transverse electric (TE) or transverse magnetic (TM) polarized light. The first oxidation potential on absorbed monolayers was found by cyclic voltammetry to be resolved into two peaks indicative of two electrochemically distinct subpopulations of molecules, atributed to aggregates and monomerics forms of PA functionalized ZnPcs. Potential modulated ATR (PM-ATR) spectroelechtrochemistry was employed to measure the charge transfer rates constants (k(s,app)) at ITO modified surfaces using TE and TM polarized light. Faster charge transfer rate constants were found for molecules with a smaller tunneling distance. A k(s,app) of 3.9 x 10⁴ s⁻¹ represents the fastest rate measured for PA functionalized ZnPc chromophore tethered to an ITO waveguide electrode by PM-ATR. We synthesized and characterized the first examples of PA functionalized RuPcs to investigate the effect of molecular orientation on charge transfer properties at an ITO/organic interface. PA functionalized RuPcs have the ability to coordinate axial ligand to suppress aggregation, providing the flexibility of connecting the anchoring group through the axial position of the metal and allowing chemisorption of the molecule in plane with ITO. Cyclic voltammetry and ATR UV/vis spectroscopy on the modified ITO surface demonstrated a surface composition of a closed-packed monolayer of monomeric species. Measurement of the charge transfer rates constants demonstrated that RuPc anchored to ITO exhibited slow rates compared to corresponding surface bound ZnPcs. Finally, we describe the synthesis and characterization of a new PA functionalized N-pyridinyl perylenediimide (PDI)-RuPc donor-acceptor dyad capable of chemisorption to ITO surfaces as a molecular-level heterojunction system to study photo induced charge separated states. The developed ensemble was proven to be stable on ITO for further study of charge injection events from the dyad to the oxide surface.
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Centrone, Charla Anne. "Synthesis of C-phosphonic acid, C-phosphinic acid, and C-sulfone analogs of decaprenolphosphoarabinose inhibitors of mycobacterial arabinosyltransferases /." Connect to this title online, 2003. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1054062979.
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Thesis (Ph. D.)--Ohio State University, 2003.Document formatted into pages; contains xvi, 371 p.; also contains graphics. Includes bibliographical references. Abstract available online via OhioLINK's ETD Center; full text release delayed at author's request until 2005 May 5.
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Sebah, Majda. "Novel Synthetic and Evaluation Studies on Phosphonic Acid Functlonalised Periodic Hybrid Materials." Thesis, Queen Mary, University of London, 2010. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.520461.
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Hotchkiss, Peter J. "The design, synthesis, and use of phosphonic acids for the surface modification of metal oxides." Diss., Atlanta, Ga. : Georgia Institute of Technology, 2008. http://hdl.handle.net/1853/31836.
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Thesis (Ph.D)--Chemistry and Biochemistry, Georgia Institute of Technology, 2009.Committee Chair: Marder, Seth; Committee Member: Bredas, Jean-Luc; Committee Member: Kroger, Nils; Committee Member: Perry, Joe; Committee Member: Sandhage, Ken. Part of the SMARTech Electronic Thesis and Dissertation Collection.
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Senior, Geoffrey David. "The role of dissolved metal ionic species in the phosphonic acid flotation of cassiterite." Thesis, University of British Columbia, 1987. http://hdl.handle.net/2429/27527.
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The techniques of X-ray photoelectron spectroscopy (XPS), secondary ionization mass spectroscopy, chemical abstraction analysis and microelectrophoresis were used to confirm the existence of iron films on cassiterite grains recovered from the tin concentrator of Renison Limited (Australia). All analyses indicated the level of surface iron contamination to be far in excess of that characteristic of the bulk mineral lattice. No evidence was found in XPS analyses to support the contention that this iron represented lattice iron that had accumulated on the surface due to migration through the lattice, as has been suggested to be the case for certain sulphide minerals. Instead, all of the experimental data supported the hypothesis that the surface film was the result of previous adsorption of hydrous ferric oxide sols onto the cassiterite surface in the plant environment but which had undergone fundamental structural changes when the sample was dried. Specifically, the presence of the iron film did not change significantly the electrokinetic properties of cassiterite, as is known to be the case for other insoluble oxide minerals in the presence of freshly precipitated hydrolyzed metal ionic species. To reconcile these observations, it was shown independently that drying, both thermally and under vacuum, caused the charge reversal phenomena related to hydrolyzed metal ion adsorption either to diminish or disappear. In the presence of styryl phosphonic acid, the iron contaminated cassiterite exhibited a microflotation response that corresponded remarkably with the actual flotation observed in the plant from which it was taken. A critical examination of the literature revealed that this behaviour was indicative of that reported for other cassiterites in both batch and plant flotation of ores. Most notably the mineral floated strongly between pH 4.0 and 7.5. However, after acid leaching, the pH of maximum recovery moved to more acidic values around pH 2.0 and the mineral floated much less strongly in the slightly acidic to alkaline range. This latter behaviour correlated with a large body of published data for which it was known that the cassiterite used was either a high purity sample, not exposed to solutions containing dissolved metal ionic species, or had been acid cleaned prior to test work. Conversely, results from fundamental studies, where this was known not to be the case, exhibited remarkable consistency with the data obtained for the untreated cassiterite sample.
The principal influence of the iron species adsorbed onto the surface of cassiterite was shown to be flotation activation in the pH range where the adsorbed species were not extensively solubilized. In the acidic range below pH 4.0, solubilization of the surface iron entities occurred which caused a severe flotation depressant effect. This solubilization was promoted in the presence of sodium fluoride, a known complexing agent for iron in acidic solutions, and the phosphonic acid. In the latter case, evidence was found for the formation of a soluble iron phosphonate complex. Independent confirmation was also sought and obtained from light scattering photometry to verify the strong affinity of phosphonic acids for hydrous ferric oxide species. Other ionic entities, such as those of magnesium and calcium were found to interact far less strongly.
On the basis of this research, it has proven possible to provide a rational interpretation of all previously existing data pertaining to cassiterite flotation with phosphonic acids, for which reasonable sample description and preparation information exist. Such a reconciliation has not previously been provided, either through studies on the effects of cassiterite mineral lattice impurities or other work with dissolved metal ionic species. Furthermore, a significant link has been established between the results of fundamental analyses and industrial related observations. In particular, commercially successful practices, such as fluoride pretreatment of ore slurries prior to cassiterite flotation, now can be interpreted successfully in terms of fundamental ion solution chemistry. The evidence is that such processes involve the solubilization under acidic conditions of adsorbed iron hydroxy sols from the surface of minerals prior to cassiterite flotation. A bulk rejection of the complexed metal ionic species is then made in the water split of the desliming circuit that precedes flotation. The solution chemical evidence obtained supporting such a mechanism is considerable and no finding, in this work or elsewhere, refutes it.Applied Science, Faculty of
Mining Engineering, Keevil Institute of
Graduate
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Wood, Christopher Alan. "Theoretical investigation of polar zinc oxide surface modification via phosphonic acid self-assembled monolayers." Thesis, Georgia Institute of Technology, 2012. http://hdl.handle.net/1853/43584.
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The interface of a zinc-terminated polar zinc oxide surface (0002) with a series of chemisorbed fluorinated benzylphosphonic acids has been studied using density functional theory. The calculations indicate that there is a substantial change in the binding energies and work function modification depending on the binding motif. The results also indicate that there is a pronounced difference in the magnitude and trends of the factors determining the total change in work function. The oxygen core-level binding shifts have been calculated and compared to available experimental data.
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Labalme, Etienne. "Synthesis and characterizations of new fluorinated membranes bearing pendant phosphonic acid groups for PEMFC application." Thesis, Montpellier, Ecole nationale supérieure de chimie, 2013. http://www.theses.fr/2013ENCM0013.
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Ce travail de thèse s'inscrit dans la continuité des travaux de recherche réalisés sur le développent de nouvelles membranes échangeuses de protons pour piles à combustibles de type PEMFC, porteuses de groupements protogènes acides phosphoniques. L'objectif de ces travaux est d'apporter des solutions permettant l'amélioration des propriétés physico-chimiques d'un copolymère phosphoné, le poly(CTFE-alt-VEPA) obtenu à partir de la polymérisation radicalaire de vinyl éthers et de CTFE. La première stratégie employée est une stratégie Blend. Elle consiste à ajouter un polymère fluoré commercial, le poly(VDF-co-CTFE), lors de la mise en forme de la membrane. Les membranes ainsi obtenues montrent d'excellentes propriétés mécaniques et des valeurs de conductivité protonique acceptable. Cependant, lors de l'acidification du polymère phosphoné, une légère dégradation est observée. Une nouvelle technique de réticulation a alors été mise en place afin d'augmenter la stabilité vis-à-vis des acides. La réticulation de ces membranes blend a de plus permis d'améliorer la miscibilité entre le polymère fluoré et le polymère phosphoné. Enfin, les derniers travaux de cette thèse concernent la synthèse de copolymère à bloc à partir d'une stratégie RAFT. Ainsi la polymérisation radicalaire contrôle de monomère phosphoné a pu être réaliséeThis work is a continuation of research conducted on the development of new proton exchange membrane fuel cell (PEMFC), bearing phosphonic acid as protogenic groups. The aim of this work is to provide solutions with a view to improving the physicochemical properties of a phosphonate copolymer, poly(CTFE-alt-VEPA) obtained from the radical polymerization of vinyl ethers and CTFE. The first strategy used is a Blend strategy. It consists of adding a commercial fluorinated copolymer, poly(VDF-co-CTFE), during the casting of the membrane. The membranes thus obtained show excellent mechanical properties and acceptable values of proton conductivity. However, during the acidification of membrane, a slight degradation of the phosphonate copolymer is observed. A new technique of crosslinking was then established to increase the stability versus acids. The crosslinking of the blend membranes has also helped to improve the miscibility between the fluorinated copolymer and phosphonate polymer. Finally, the last work of this thesis relate to the synthesis of block copolymer from a RAFT strategy. Thus, the controlled radical polymerization of monomer phosphonated was achieved
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Helfrich, Marcus Robert. "Preliminary investigations into the development of novel layered phosphonic acid vesicles for targeted drug delivery applications /." view abstract or download file of text, 2002. http://wwwlib.umi.com/cr/uoregon/fullcit?p3045088.
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Thesis (Ph. D.)--University of Oregon, 2002.Typescript. Includes vita and abstract. Includes bibliographical references (leaves 184-193). Also available for download via the World Wide Web; free to University of Oregon users. Address: http://wwwlib.umi.com/cr/uoregon/fullcit?p3045088.
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Wells, Christopher J. "The equilibrium characteristics of aqueous cobalt and nickel mixtures with the extractant bis-(2-ethylhexyl)-phosphonic acid." Thesis, University of Ottawa (Canada), 1991. http://hdl.handle.net/10393/7545.
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In this work, binary solutions of cobalt and nickel in aqueous ammonium sulfate solutions were extracted using a simple shake-out technique with a mixed organic phase consisting of the extractant bis-(2-ethylhexyl)phosphonic acid (PC-88A), the modifier tributyl phosphate, and the diluent Esso Varsol DX3641. It was found that the optimum pH for the separation of cobalt and nickel was 5.0, and that the separation of the ions was a complex function of the porportion of cobalt and nickel in the equilibrium phases. The maximum metal loading of the organic phase, based on the population of dimer extractant complexes was approximately 73%. Two methods, used to describe the equilibrium extraction of two or more metal ions were compared namely, the Delta Y method and the Pseudo-Gamma approach. Each of these methods account for the non-ideal interactions between mixture components. Barclay's Pseudo-Gamma relationship was found to be simpler, and correlated the data very well. (Abstract shortened by UMI.)
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Wharmby, Michael T. "Synthesis of porous metal phosphonate frameworks for applications in gas separation and storage." Thesis, University of St Andrews, 2012. http://hdl.handle.net/10023/3450.
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Porous metal phosphonate framework materials were synthesised by solvothermal reaction of bis(α-aminomethylenephosphonic acid) ligands with divalent and trivalent metal cations. The syntheses and characterisation by NMR and, where possible, single crystal X-ray diffraction of seven bisphosphonic acid ligands, including N,N′-piperazinebis(methylenephosphonic acid) (H₄L), its racemic and enantiopure (R) 2-methyl (H₄L′ and R-H₄L′) and 2,5-dimethyl (H₄L′′) derivatives, and N,N′-4,4′-bipiperidinebis(methylenephosphonic acid) (H₄LL) are reported. Syntheses of the known phase Y₂(LH₂)₃·5H₂O and the new phases, STA-13(Y) (St Andrews microporous material No. 13) and Y₂(R-L′H₂)₃·4H₂O, from reactions of Y(AcO)₃ with H₄L, H₄L′ and R-H₄L′ respectively are reported. The as-prepared and dehydrated structures of each phase have been determined from either laboratory or synchrotron powder X-ray diffraction data. Reaction of Y(AcO)₃ and H₄L′′ is shown to form a phase with a different structure. The features determining which structure crystallises are discussed. Syntheses of other rare-earth forms of STA-13 (Sc³⁺, Gd³⁺–Yb³⁺) and the porosity of each phase to N₂ are reported. STA-13(Y) is the most porous form with loadings of ∼3 mmol g⁻¹ and ∼4 mmol g⁻¹ for N₂ and CO₂ respectively. MIL-91(Fe) was synthesised for the first time from reactions of Fe³⁺ cations with H₄L. Its structure was confirmed by Rietveld refinement, but it was not porous. The first syntheses of [Fe₄L₁.₅(AcO)₁.₅(OH,H₂O)₃]·0.5NH₄5.5H₂O (L= L or L′) are reported, from reactions of H₄L or H₄L′ in the presence of an excess of Fe³⁺ cations. The phase is related to a previously reported Co phase. The synthesis of divalent metal bisphosphonate STA-12(Mg) (Mg₂(H₂O)₂L·5.6H₂O) was reported for the first time and its structure determined from single crystal X-ray diffraction. The dehydration behaviour of this material was compared with the known forms of STA-12. STA-12(Mg) is porous to both N₂ (∼5.5 mmol g⁻¹) and CO₂ (~ 8.5 mmol g⁻¹). Reaction of H₄LL with Co²⁺ and Ni²⁺ gave two materials isoreticular with STA-12, labelled STA-16(Co) and STA-16(Ni). The structures of both materials were solved from synchrotron powder X-ray diffraction data. On dehydration, STA-16(Co) undergoes a reversible structural transition to an unknown structure. By contrast, STA-16(Ni) retains the same symmetry in the dehydrated form and its structure was determined from synchrotron powder X-ray diffraction data. Both materials are porous to N₂, with an uptake of up to 22.2 mmol g⁻¹, and CO₂ with maximum loading of 21.7 mmol g⁻¹. NLDFT analysis of N₂ adsorption data confirm the crystallographically determined pore radii. Syntheses of other frameworks with divalent cations and initial reactions of H₄LL with trivalent cations are also reported.
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Romson, Tomas. "Triazine-based adhesive : An adherence study on clinically used metal surfaces." Thesis, KTH, Ytbehandlingsteknik, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-278862.
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When a material is adhered onto a specific surface it is relevant to know how to make thematerial stay on the surface. By investigating different primers to use with a triazine-basedadhesive, further improvements to using the adhesive on metals can be achieved. This studyfound that an adhesive of (2,4,6-trioxo-1,3,5-triazinane-1,3,5-triyl)tris(ethane-2,1-diyl)tris(3-mercaptopropanoate) (TEMPIC) and 1,3,5-triallyl-1,3,5-triazinane-2,4,6-trione(TATATO) adhered to titanium and stainless steel, two clinically used metal surfaces. Itfurther found that between a phosphonic acid primer, a biomimetic catechol primer and acommercially available silane primer the phosphonic acid primer gave the best adhesion.These results could be because of a higher amount of crosslinking for the phosphonic acidprimer. For further testing increased pH and increased amount as well as increasedhydrolysation time for the catechol and silane primers respectively is suggested. Shearstrength testing was used to determine the adhesion strength. The shear strength testswere done with conditioning in phosphate buffer saline (PBS) solution for 24h beforehand
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Tramaux, Axel. "Synthèse de nouveaux superplastifiants phosphonés et évaluation de leur efficacité sur des suspensions de carbonate de calcium." Thesis, Montpellier, 2018. http://www.theses.fr/2018MONTS009/document.
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Les superplastifiants sont des adjuvants permettant de considérablement fluidifier les pâtes cimentaires sans en changer le rapport eau/ciment. Parmi eux, les polycarboxylates sont les plus utilisés et les plus étudiés. Ces copolymères en peigne sont porteurs de fonctions acide carboxylique et de chaînes latérales de poly(ethylène glycol). Leurs fonctions anioniques leur permettent de s’adsorber sur les grains de ciment, tandis que les chaînes latérales génèrent de la répulsion stérique entre ces derniers. Cela conduit à la désagglomération des agglomérats, et donc la dispersion des particules. Macroscopiquement, la pâte cimentaire devient plus fluide, plus facile à mettre en oeuvre. Mais dans certaines circonstances, la présence d’anions compétiteurs peut réduire la capacité d’adsorption et donc l’efficacité des polycarboxylates. De nombreux auteurs ont tenté d’améliorer les performances de ces structures en modifiant l’architecture macromoléculaire. Parmi ces travaux, des chercheurs ont remplacé les acides carboxyliques par des fonctions acide phosphonique, et cela a considérablement amélioré la résistance des superplastifiants au phénomène de compétition ionique.Ce travail de thèse rapporte la synthèse d’une dizaine de nouveaux copolymères en peigne, de structure proche de polycarboxylates classiques mais possédant des fonctions phosphonées. Ces copolymères ont été obtenus par télomèrisation ou bien par polymérisation radicalaire RAFT. Leurs performances ont ensuite été évaluées sur des suspensions minérales de carbonate de calcium, un matériau modèle souvent utilisé pour modéliser le comportement du ciment aux premiers âges de son hydratation. Les efficacités d’adsorption, de dispersion des particules minérales et de fluidification des suspensions ont ainsi été investiguées et mises en relation avec la structure macromoléculaire. De plus, leur résistance à la compétition ionique a également été examinée à travers l’augmentation de la force ionique par ajouts de sulfate de sodium et de nitrate de sodium.Enfin, ce manuscrit rapporte la tentative de conception d’un superplastifiant biosourcé à travers la fonctionnalisation d’oligomères de chitosan par des fonctions phosphonées et des chaînes latérales de poly(éthylène glycol). Les efficacités d’adsorption, de dispersion et de fluidification des suspensions de calcite de ce composé biosourcé ont finalement été évaluées et comparées à celles des copolymères en peigne de synthèseSuperplasticizers are admixtures allowing the fluidification of cement pastes without any changes of the water/cement ratio. Among them, polycarboxylates are the most used and the most studied. These comb-like copolymers have carboxylic acid moieties and poly(ethylene oxide) side chains. Their anionic functions make possible their adsorption onto cement grains while side chains create steric repulsion between these latter. This leads to deagglomeration and dispersion of particles. From a macroscopic point of view, cement paste becomes more fluid, easier to place. But in some cases, competitive anions can reduce their adsorption ability and thus polycarboxylates dispersion efficiency. Lots of authors tried to improve structures performances by modifying macromolecular architecture. Among these works, some searchers have replaced carboxylic acids by phosphonic acid moieties, and this greatly improved superplasticizers resistance to ionic competition phenomenon.This work focuses on the synthesis of several new comb-like copolymers, whose structures are similar to conventional polycarboxylates but with phosphonic acid functions instead of carboxylic acids. These copolymers were obtained from telomerization or RAFT copolymerization. Their performances were evaluated on calcium carbonate suspensions, a model material widely used to simulate early-age cement behavior. Adsorption, dispersion and fluidification efficiencies of synthetized copolymers were examined and linked to their macromolecular structures. Moreover, their resistance to ionic competition was investigated through the increase of ionic strength by addition of sodium sulfate and sodium nitrate.Finally, this manuscript relates the conception of a biobased superplasticizer through the functionalization of oligomers of chitosan by phosphonated functions and poly(ethylene oxide) side chains. Adsorption, dispersion and fluidification efficiencies of this biobased compound were evaluated on calcite suspensions and compared to those of previously synthetized comb-like copolymers
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GOLLA, VINAYA KUMAR [Verfasser], Ulrich [Akademischer Betreuer] Kleinekathöfer, Ulrich [Gutachter] Kleinekathöfer, Mathias [Gutachter] Winterhalter, Roland [Gutachter] Benz, and Lars [Gutachter] Schäfer. "Translocation of Phosphonic Acid Antibiotics Through Bacterial Outer Membrane Channels / VINAYA KUMAR GOLLA ; Gutachter: Ulrich Kleinekathöfer, Mathias Winterhalter, Roland Benz, Lars Schäfer ; Betreuer: Ulrich Kleinekathöfer." Bremen : IRC-Library, Information Resource Center der Jacobs University Bremen, 2021. http://d-nb.info/1225937787/34.
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Chen, Alfred Yuen-Wei. "Synthesis and Functionalization of Poly(ethylene oxide-b-ethyloxazoline) Diblock Copolymers with Phosphonate Ions." Thesis, Virginia Tech, 2013. http://hdl.handle.net/10919/23930.
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Poly(ethylene oxide) (PEO) and poly(2-ethyl-2-oxazoline) (PEOX) are biocompatible
polymers that act as hydrophilic "stealth" drug carriers. As block copolymers, the PEOX group
offers a wider variety of functionalization. The goal of this project was to synthesize a
poly(ethylene oxide)-b-poly(2-ethyl-2-oxazoline) (PEO-b-PEOX) block copolymer and
functionalize pendent groups of PEOX with phosphonic acid. This was achieved through
cationic ring opening polymerization (CROP) of 2-ethyl-2-oxazoline monomer onto PEO. These polymerizations used tosylsulfonyl chloride as initiator. Size-exclusion chromatography (SEC) was used to determine the molecular weights of the block copolymers. Two samples of 1:2 and one sample of 1:3 of PEO-to-PEOX block copolymers were made. These samples underwent partial hydrolysis of the PEOX pendent groups to form the random block copolymer, poly(ethylene oxide)-b-poly(2-ethyl-2-oxazoline)-co-poly(ethyleneimine) (PEO-b-PEOX-co-PEI). These reactions showed that there was a degree of control based on the moles of acid. Diethyl vinyl phosphonate was attached to the nitrogen of PEI units via Michael addition where the phosphorylation left <1% of PEI units unattached. The ethyl groups on the phosphonates were further hydrolyzed off phosphonate with HCl acid leaving phosphonic acid. After each step of synthesis, structures and composition were confirmed using 1H NMR. Due to the nature of the phosphonic acid, the polymer can be utilized in the incorporation and release of cationic drugs.Master of Science
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Nilsing, Mattias. "Computational Investigation of Dye-Sensitized Solar Cells." Doctoral thesis, Uppsala universitet, Avdelningen för kvantkemi, 2007. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-7673.
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Interfaces between semiconductors and adsorbed molecules form a central area of research in surface science, occurring in many different contexts. One such application is the so-called Dye-Sensitized Solar Cell (DSSC) where the nanostructured dye-semiconductor interface is of special interest, as this is where the most important ultrafast electron transfer process takes place. In this thesis, structural and electronic aspects of these interfaces have been studied theoretically using quantum chemical computations applied to realistic dye-semiconductor systems. Periodic boundary conditions and large cluster models have been employed together with hybrid HF-DFT functionals in the modeling of nanostructured titanium dioxide. A study of the adsorption of a pyridine molecule via phosphonic and carboxylic acid anchor groups to an anatase (101) surface showed that the choice of anchor group affects the strength of the bindings as well as the electronic interaction at the dye-TiO2 interface. The calculated interfacial electronic coupling was found to be stronger for carboxylic acid than for phosphonic acid, while phosphonic acid binds significantly stronger than carboxylic acid to the TiO2 surface. Atomistic and electronic structure of realistic dye-semiconductor interfaces were reported for RuII-bis-terpyridine dyes on a large anatase TiO2 cluster and perylene dyes on a periodic rutile (110) TiO2 surface. The results show strong influence of anchor and inserted spacer groups on adsorption and electronic properties. Also in these cases, the phosphonic acid anchor group was found to bind the dyes significantly stronger to the surface than the carboxylic acid anchor, while the interfacial electronic coupling was stronger for the carboxylic anchor. The estimated electron injection times were twice as fast for the carboxylic anchor compared to the phosphonic anchor. Moreover, the electronic coupling was affected by the choice of spacer group, where unsaturated spacer groups were found to mediate electron transfer more efficiently than saturated ones.
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Zheng, Yilong, Fadi M. Jradi, Timothy C. Parker, Stephen Barlow, Seth R. Marder, and S. Scott Saavedra. "Influence of Molecular Aggregation on Electron Transfer at the Perylene Diimide/Indium-Tin Oxide Interface." AMER CHEMICAL SOC, 2016. http://hdl.handle.net/10150/622363.
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Chemisorption of an organic monolayer to tune the surface properties of a transparent conductive oxide (TCO) electrode can improve the performance of organic electronic devices that rely on efficient charge transfer between an organic active layer and a TCO contact. Here, a series of perylene diimides (PDIs) was synthesized and used to study relationships between monolayer structure/properties and electron transfer kinetics at PDI-modified indium-tin oxide (ITO) electrodes. In these PDI molecules, one of the imide substituents is a benzene ring bearing a phosphonic acid (PA) and the other is a bulky aryl group that is twisted out of the plane of the PDI core. The size of the bulky aryl group and the substitution of the benzene ring bearing the PA were both varied, which altered the extent of aggregation when these molecules were absorbed as monolayer films (MLs) on ITO, as revealed by both attenuated total reflectance (ATR) and total internal reflection fluorescence spectra. Polarized ATR measurements indicate that, in these MLs, the long axis of the PDI core is tilted at an angle of 33-42 degrees relative to the surface normal; the tilt angle increased as the degree of bulky substitution increased. Rate constants for electron transfer (k(s,opt)) between these redox-active modifiers and ITO were determined by potential-modulated ATR spectroscopy. As the degree of PDI aggregation was reduced, k(s,opt) declined, which is attributed to a reduction in the lateral electron self-exchange rate between adsorbed PDI molecules, as well as the heterogeneous conductivity of the ITO electrode surface. Photoelectrochemical measurements using a dissolved aluminum phthalocyanine as an electron donor showed that ITO modified with any of these PDIs is a more effective electron-collecting electrode than bare ITO.
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Starke, Sandra. "Multifunktionale (Meth)acrylat-Copolymere mit Phosphonsäurederivaten." Doctoral thesis, Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2015. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-189936.
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Ziel der Doktorarbeit war es, Copolymere mit phosphonsäurehaltigen Seitenketten zu entwickeln, die nachfolgend über polymeranaloge Umsetzungen in Terpolymere mit polymerisationsfähgen Gruppen umgewandelt werden sollten. Die Terpolymere können dann somit im Bereich der Schicht,- Lackindustrie eingesetzt werden.
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Graillot, Alain. "Synthèse et caractérisation de copolymères thermosensibles phosphonés : évaluation de leurs propriétés de sorption et séparation au sein d’un nouveau procédé de traitement d’effluents aqueux chargés en métaux." Thesis, Montpellier 2, 2013. http://www.theses.fr/2013MON20226.
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Le travail de thèse présenté dans ce manuscrit a pour objectif la synthèse de copolymères thermosensibles complexants innovants pour la mise en place d'un nouveau procédé de traitement des effluents aqueux chargés en métaux. Ce procédé original est en effet basé sur l'utilisation de copolymères porteurs de groupements phosphonés permettant la sorption des métaux en solution aqueuse et possédant un caractère thermosensible de sorte à contrôler la solubilité du copolymère et à faciliter les étapes de sorption et de séparation. Dans un premier temps, la synthèse de copolymères thermosensibles phosphonés a été réalisée par polymérisation radicalaire conventionnelle puis par polymérisation radicalaire contrôlée (PRC) ce qui a conduit à différentes architectures. Parmi les composés préparés, le P(NnPAAm-stat-hMAPC1) a été sélectionné car il présente une basse température critique de solution proche de la température des effluents industriels chargés en métaux. Les propriétés de sorption de ces copolymères ont ensuite été déterminées en réacteur statique afin de mettre en évidence les facteurs influents (temps de contact, température, pH, composition de l'effluent). Ces différents essais ont également permis d'étudier les mécanismes de sorption intervenant entre les groupements acide phosphonique et les différents cations métalliques évalués (Ni2+, Ca2+, Cd2+, Al3+). Enfin, les étapes de séparation post-sorption et de régénération ont également fait l'objet d'études approfondies, permettant de proposer à l'issue de ce travail un procédé innovant de traitement de la pollution métallique, appelé procédé TEMF (Thermosensitive polymer Enhanced Microfiltration). L'efficacité des différentes étapes constituant ce procédé a été évaluée en batch à l'échelle du laboratoire et en semi-continu sur un pilote de laboratoire conçu dans le cadre du projetThis Ph-D work aims at synthetizing thermosensitive and complexing polymers for the implementation of an innovative process targeting the removal of metallic cations from wastewater. This process is based on the use of copolymers bearing phosphonic acid groups as sorption moieties whereas thermoresponsiveness allows adjusting the solubility of the polymeric sorbent according to the process step considered. First, the synthesis of various thermosensitive copolymers bearing phosphonated moieties is reported. The use of free radical polymerization or Reversible Addition Fragmentation Transfer (RAFT) polymerization allowed synthesizing copolymers with different architectures. Among all macromolecular compounds, the P(NnPAAm-stat-hMAPC1) copolymer was chosen as the most relevant polymeric sorbent for the process. Sorption properties of this copolymer were then evaluated and results highlighted that the contact time, the temperature, the pH and more generally the effluent composition were the main influencing parameters. These studies also enable to figure out the sorption mechanisms involved between phosphonic acid and the cationic metals studied (Ni2+, Ca2+, Cd2+, Al3+).The studies carried on the separation and regeneration steps of the process allowed the development of an innovative process for the removal of metallic pollution from wastewaters named Thermosensitive polymer Enhanced Microfiltration (TEMF) process. Finally, the conception of a pilot plant permitted the study of the TEMF process at larger scale
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Cortes-Clerget, Margery. "Synthèse de nouveaux catalyseurs bifonctionnels peptidiques incluant un motif acide phosphonique pour la création de liaisons C-C énantiosélective." Thesis, Sorbonne Paris Cité, 2015. http://www.theses.fr/2015USPCD058/document.
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Une bibliothèque de nouveaux catalyseurs bifonctionnels combinant à la fois l’aminocatalyse et l’activation acide par un acide phosphonique sur une même structure peptidique a été développée. Des variations structurales ont été apportées afin d’optimiser la géométrie du site catalytique. Le potentiel de ces catalyseurs a été testé sur la réaction d’addition de Michael stéréosélective d’aldéhydes sur divers nitroalcènes aromatiques. Dans des conditions optimisées, de très bonnes sélectivités (r.d. < 95:5 / r.e. < 93:7) ont été atteintes. Grâce à leur forte solubilité dans l’eau, ces catalyseurs ont été facilement extraits et réutilisés sur 10 cycles sans perte significative de sélectivité. Enfin, des études mécanistiques ont été menées afin de connaitre le mode d’action exact de ces catalyseurs. Tant l’énamine que l’activation acide se sont avérées essentielles pour que la réaction ait lieu. L’enchainement peptidique permet une réaction intramoléculaire et stéréosélectiveA novel bifunctional organocatalyst library combining both aminocatalysis and phosphonic acid activation on a peptide structure was developed. Some structural variations allowed the optimization of the catalytic site. The potential of these catalysts was evaluated on the stereoselective Michael addition of aldehydes with several aromatic nitroalkenes. In optimized conditions, very good selectivities (up to 95:5 d.r. and 93:7 e.r) were achieved. Due to their high water-solubility, the catalysts were easily recyclable and reused over several cycles without any significant loss of selectivities. Mechanistic investigations were carried out to understand the exact mode of action of the catalysts. Both enamine formation and acid activation were essential for the reaction to occur. The peptide structure allows an intramolecular and stereoselective reaction
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Kim, Philseok. "Surface modification of nanoparticles for polymer/ceramic nanocomposites and their applications." Diss., Atlanta, Ga. : Georgia Institute of Technology, 2008. http://hdl.handle.net/1853/31651.
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Thesis (Ph.D)--Chemistry and Biochemistry, Georgia Institute of Technology, 2009.Committee Chair: Perry, Joseph W.; Committee Member: Kippelen, Bernard; Committee Member: Lyon, L. Andrew; Committee Member: Marder, Seth R.; Committee Member: Whetten, Robert L. Part of the SMARTech Electronic Thesis and Dissertation Collection.
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Hanrahan, Jane. "The synthesis of substituted phosphonic acids." Thesis, University of Warwick, 1995. http://wrap.warwick.ac.uk/55734/.
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Cyclic phosphonic acid analogues of the endogenous amino acids L-aspartic acid and L -glutamic acid have played a major role in the characterisation of excitatory amino acid receptors in the central nervous system. The aim of the first section of this work is to describe the development of a synthetic route that gives access to a novel series of compounds, 3-substituted-cyclobutanephosphonic acids. The synthesis of a valuable intermediate diethyl3-oxocyclobutanephosphonate is described. Elaboration of the ketone functionality of this compound provides allows the synthesis of a number of previously inaccessible 3-substituted-cyclobutanephosphonates, including E- and Z-3-amino-3-carboxy-cyclobutanephosphonic acid, 3-aminocyclobutanephosphonic acid and the four stereoisomers of 3-(amino-carboxymethyl)- cyclobutanephosphonic acid. Enzymatic hydrolysis of the phenyl acetyl derivative of diethyl 3-(amino-cyanomethyl)- cyclobutanephosphonate by penicillinacylase allowed the preparation of 3-(amino-carboxy-methyl)-cyc1obutane-phosphonic acid with high enantiomeric purity. The antiviral activity of phosphonoacetic acid (P AA) has long been recognised. However, a number of problems are associated with the administration of this compound as an antiviral, these include high toxicity to the hosts cells, poor uptake in to cells and absorbtion by teeth and bones. One approach to solving some of these problems may be to make the compounds more lipophilic by increasing the number of carbon atoms in the molecule. The synthesis of a number of cyclic analogues of P AA and the related bisphosphonic acids is described. These compounds are prepared by phase transfer catalysed alkylation of trialkyl phosphonoacetate and tetra alkyl methylenebisphosphonate. The antiviral activity of these compounds against Herpes simplex virus 1 (HSVl) was investigated. A series of chiral at sulfur, a-phosphoryl sulfoxides and ~-hydroxy sulfoxides were prepared. These compounds were investigated for their ability to enantioselectively catalyse the reaction between diethylzinc and benzaldehyde. Although this reaction was catalysed by all of these compounds, this action was not accompanied by enantioselectivity. Comparison of our results with those obtained for ~-hydroxy sulfoximides enabled this lack of enantioselectivity to be explained by the analysis of the proposed transition state complexes.
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Orozco, Angela Maria. "Dilute acid hydrolysis of municipal solid waste using phosphoric acid." Thesis, Queen's University Belfast, 2008. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.501392.
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Bassil, Joëlle. "Développement par procédés plasma de polymères conducteurs protoniques de type phosphonique pour piles à combustible." Thesis, Montpellier 2, 2014. http://www.theses.fr/2014MON20029/document.
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Afin de rendre les piles à combustible de type PEMFC réellement compétitives, un certain nombre d'inconvénients liés à l'utilisation du Nafion® restent à contourner, en particulier sa mauvaise conductivité protonique à des températures supérieures à 80°C. Dans l'optique de pouvoir opérer à plus hautes températures (jusqu'à 120°C), le développement de membranes moins sensibles à l'eau s'avère donc déterminant. Les polymères à base de fonctions acide phosphonique sont considérés comme des candidats potentiels pour une intégration en tant que matériau électrolyte dans les PEMFC « hautes températures » (> 80°C) grâce à leur fort caractère amphotère qui leur confère une bonne conductivité protonique dans des conditions d'humidité réduites. Dans ce contexte, la majeure partie de ce travail de thèse concerne l'élaboration par polymérisation plasma (PECVD) de polymères à base de groupements acide phosphonique à partir du monoprécurseur diméthyl allyl phosphonate. Dans un premier temps, nous avons démontré la faisabilité d'élaborer par polymérisation plasma des polymères à base de fonctions acide phosphonique à partir d'un monoprécurseur. Nous avons confirmé par IRTF, EDX et XPS la présence des groupements acide phosphonique favorables au transport protonique et l'homogénéité de la composition chimique de la surface jusqu'au cœur du matériau plasma. Les matériaux plasma montrent une bonne stabilité thermique dans la gamme de température 80°C - 120°C. Ensuite, une optimisation des conditions de synthèse a été réalisée. Les plus importantes valeurs de vitesses de croissance (28 nm.min-1 sur plaquette de silicium, 22 nm.min-1 sur PTFE et 26 nm.min-1 sur Nafion®211), de CEI (4,65 meq.g-1) et de conductivité (0,08 mS.cm-1 à 90°C et 30% RH) sont celles de la membrane synthétisée à 60 W. Des mesures de perméabilité au méthanol, à l'éthanol et au glycérol ont été réalisées et montrent que les films plasma sont intrinsèquement 40 à 235 fois moins perméables au combustible que le Nafion®211 du fait de leur fort taux de réticulation. Les polymères ont été déposés en tant que liants sur des électrodes E-TEK® pour intégration en pile. Nous avons constaté que le liant phosphonique plasma possède une conductivité protonique suffisante pour permettre le transport des protons à l'interface membrane-électrodes. En parallèle, nous avons réalisé le traitement de surface par plasma d'une membrane phosphonique conventionnelle pour en améliorer la stabilité thermique et la rétention au combustible. Les analyses thermogravimétriques montrent une légère amélioration de la stabilité thermique suite au traitement de surface. Des tests de perméabilité au méthanol et à l'éthanol montrent que la membrane traitée par plasma est 2 à 4 fois moins perméable que la membrane vierge. Le traitement à 60 W conduit aux coefficients de diffusion les plus faibles (DMeOH = 9.10-12 m2.s-1 et DEtOH = 6.10-12 m2.s-1). Des tests en pile ont été effectués montrant de meilleures performances de la membrane traitée en comparaison de son homologue non traitéThe proton exchange membrane is a key component in the PEMFC-type fuel cell; it plays a decisive role as electrolyte medium for proton transport and barrier to avoid the direct contact between fuel and oxygen. The Nafion® is one of the most extensively studied proton exchange membrane for PEMFC applications. However, it has a number of drawbacks that need to be overcome, especially the poor performance at temperature above 80°C. That's why the development of effective and low cost membranes for fuel cell turned to be a challenge for the membrane community in the last years. Phosphonic acid derivatives are considered suitable candidates as ionomers for application in PEMFC at high temperature (> 80°C) thanks to their efficient proton transport properties under low humidity condition due to their amphoteric character.In this work, plasma polymers containing phosphonic acid groups have been successfully prepared using dimethyl allylphosphonate as a single precursor demonstrating the feasibility of plasma process for the manufacture of proton exchange membranes. Moreover, plasma polymers properties have been investigated as a function of the plasma conditions. The evolution of the films growth rate on three different supports as a function of the plasma discharge power is bimodal, with a maximum (close to 30 nm min-1 on Si) at 60 W. The chemical composition of plasma materials (investigated by FTIR, EDX and XPS) is quite homogeneous from the surface to the bulk; it is characterized by a wide variety of bond arrangements, in particular the presence of phosphonate and phosphonic acid groups which are above all concentrated in the plasma film synthesized at 60 W, characterized by the highest ion exchange capacity (4.65 meq g-1) and the highest proton conductivity (0.08 mS cm-1 at 90°C and 30% RH). TGA analysis has shown that phosphonic acid-based plasma polymers retain water and don't decompose up to 150 °C, which reveals a satisfying thermal stability for the fuel cell application. In terms of fuel retention, plasma films are intrinsically highly performing (methanol, ethanol and glycerol permeabilities being 40 to 235 lower than that of Nafion®211). The plasma films were deposited on fuel cell electrodes (E-TEK®) as binding agents. We have noticed that the phosphonic binder has a sufficient proton conductivity to allow proton transport at the electrode-membrane interface.A second part of this work concerns the surface treatment by plasma process of a conventional phosphonated membrane for improvement of thermal stability and fuel retention. TGA analysis has shown a slight improvement of the thermal stability for the treated membrane. Methanol and ethanol permeabilities tests show that the plasma-modified membrane is 2 to 4 times less permeable than the non-modified membrane. The treatment at 60 W shows the lowest fuel diffusion coefficients (DMeOH = 9.10-12 m2.s-1 and DEtOH = 6.10-12 m2.s-1). Fuel cell tests were realized showing better performance for the modified membrane compared to the non-modified one
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Laurent, Grégory. "Réactions de cycloadditions énantiosélectives catalysées par des dérivés d’acides de Brønsted chiraux." Thesis, Paris 11, 2014. http://www.theses.fr/2014PA112419.
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Ces travaux de thèse avaient pour objectif la synthèse asymétrique d’hétérocycles énantioenrichis par des méthodes à hautes valeurs ajoutées. Pour cela des catalyseurs ont été employés dans des réactions de cycloaddition. D’une part, l’organocatalyse asymétrique permet d’utiliser un matériel chiral peu coûteux en faible quantité pour générer des produits chiraux, d’autre part, les réactions de cycloadditions permettent une économie d’atome certaine et la création de plusieurs liaisons en une réaction.La première partie de cette thèse concerne des réactions de cycloadditions d’aza-Diels-Alder à demande inverse en électrons. Ces travaux mettent en jeu des 1-Azadiènes et des énecarbamates pour générer des tétrahydropyridines possédant 3 centres stéréogènes contigus.Les produits ont été obtenus sous la forme d’un seul diastéréomère avec de bons rendements et de bons excès énantiomérique. La modification des substrats sur diverses positions a été possible sans influencer l’efficacité de la réaction.Dans la seconde partie, une réaction de cycloaddition entre des quinones et des énecarbamates a été étudiée. L’utilisation d’un acide phosphorique à squelette SPINOL s’est révélée très efficaces, menant à des 2,3-Dihydrobenzofuranes optiquement actifs. Les produits sont isolés avec d’excellents rendements et excès énantiomériques, mais des ratios diastéréomériques faibles. Ces derniers peuvent être améliorés en engageant des énethiocarbamates.Une cascade réactionnelle peut aussi être effectuée en formant la quinone in situ à l’aide d’un réactif hypervalent iodé. L’étendue de notre cycloaddition ainsi que sa variante initié par du PIDA est conséquente mais reste encore à améliorer. Différentes hydroquinones seront ainsi évaluées. Les cycloadduits seront ultérieurement transformés de manière à valoriser cette méthodologie. Les configurations relatives et absolues des centres asymétriques formés seront déterminées avec précision par cliché de diffraction des rayons X. Ces pistes sont en cours d’étude et de réalisation au laboratoire.Enfin, la dernière partie concerne une réaction de cycloaddition 1,3-Dipolaire entre des nitrones et des énecarbamates. Si l’utilisation d’un acide phosphorique ne s’est pas révélée efficace, l’utilisation d’un phosphate de cuivre est en revanche convaincante. Initialement, la réaction a montré d’excellents résultats, malheureusement non reproductibles. Une optimisation rigoureuse a été nécessaire pour obtenir des résultats satisfaisants. Cette réaction nécessite une évaluation de son étendue vis-À-Vis des énecarbamates. Des transformations sont également envisagées pour valoriser cette méthodologieThis thesis works were aimed the asymmetric synthesis of optically pure heterocycles by high added value methodology. On one hand, the asymmetric organocatalysis allows using an inexpensive chiral materials in small quantities to generate chiral products, on the other hand, the cycloaddition reactions allow atom economy and the creation of several bonds in one reaction.The first part of this thesis concerns inverse electron demand aza-Diels-Alder cycloaddition reaction. These works involve 1-Azadienes and enecarbamates to generate tetrahydropyridines with three contiguous stereocenters.The products were obtained as a single diastereomer in good yields and good enantiomeric excess. The modification of substrates at various positions was possible without influencing the efficiency of the reaction.In the second part, a cycloaddition reaction between quinones and enecarbamates was studied. The use of a backbone SPINOL phosphoric acid proved to be very effective, leading to optically active 2,3-Dihydrobenzofurans. The products are isolated in excellent yields and enantiomeric excesses, but low diastereomeric ratios. These can be improved by engaging enethiocarbamates.A cascade reaction may also be carried out by forming the quinone in situ with a hypervalent iodine reagent. The scope of our cycloaddition and its variant initiated by PIDA is substantial but still needs to be improved. Different hydroquinones will thus be evaluated. The cycloadducts will later be transformed to develop this methodology.The last part concerns a 1,3-Dipolar cycloaddition reaction between nitrones and enecarbamates. If the use of a phosphoric acid has not proved effective, using a copper phosphate is convincing. Initially, the reaction shown excellent results, unfortunately not reproducible. A rigorous optimization was necessary to obtain satisfactory results. This reaction requires an assessment of its extent. Transformations are also envisaged to enhance the methodology
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Cao, Edgar. "Towards designing composite membranes for CO2 separation : the inclusion of hybrid TiO2-PEG structures and study of their interfaces." Thesis, Bordeaux, 2015. http://www.theses.fr/2015BORD0203/document.
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Ce travail de thèse vise à concevoir de nouvelles membranes performantes pour la séparation de gaz (CO2) dans le procédé de post-combustion. La stratégie proposée repose sur la préparation de membranes hybrides organiques/inorganiques, combinant des supports poreux de dioxyde de titane (TiO2) intégrés dans une couche dense de polymère à base de poly-oxyde d'éthylène. L'un des points important de cette étude est l'ancrage de la phase organique sur le support inorganique. Deux agents de couplage : le propyl phosphonique acide 2-bromo-2-méthyl propanoate et le 3--propylamino triéthoxy silan ont été sélectionnés et greffés sur trois surface de TiO2 différentes : des nanoparticules, des surfaces denses et des surfaces poreuses. Pour chacune des deux molécules d'ancrage les meilleurs résultats ont été obtenus avec les nanoparticules. Les nanoparticules de TiO2 ainsi fonctionnalisées, ont dans une seconde étape, servi de semences pour l'élaboration de particules coeur-écorce. Deux voies de polymérisation ont été explorées avec succès : la si-ATRP et la si-ROMP. Dans le premier cas des greffons de poly-poly-éthylène glycol méthyl éther méthacrylate ont été introduits sur les nanoparticules de TiO2. Pour la si-ROMP les greffons incorporés sont à base de polynorbonène. Les résultats obtenus sur les nanoparticules de TiO2 ont été exploités afin de créer des couches polymères sur des supports poreux céramiques tubulaires commerciaux. Deux modes de conception ont été développés : la voie dite "coating onto" et celle dite "Grafting from". Les membranes composites obtenues par ces deux voies ont été testées en perméabilité des gaz afin de déterminer la qualité des couches polymères. Des essais préliminaires de séparation des gaz ont été également effectuésThis thesis work aims towards designing hybrid membranes for CO2 separation in the post-combustion process. The different methods of existing technologies are compared ans assessed for their merit, and the decision of using inorganic titanium dioxide supports integrated with a grown polymeric/PEG layer is made. First, the structure of the interfacing group is determined and narrowed down to phosphonic-based anchoring groups. The modification of various titanium oxide surfaces (i.e. particle, flat and porous) is performed with each group, and particles were found to yield the highest surface modification. Secondly, the functionalized particles of titania were then studied for their potential with si-ATRP and si-ROMP. in the case of phosphonic acid functionalized titania, the particles yielded a bromine terminus that could be used for si-ATPR. In the case of the silane grafted titania particles, further fonctionalization was required to ultimately yield a norbornenyl group that can be used for Si-ROMP. Both teechniques were shown to work, and were thus applied to longer ceramic tubes. Finally the development of two pathways ("Coating onto" and "Grafting from") were assessed for their ability to modify the tubular ceramic support and preliminary gas separation tests were performed
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Chen, Ran S. M. Massachusetts Institute of Technology. "Magnetic gels for uranium recovery from wet phosphoric acid." Thesis, Massachusetts Institute of Technology, 2017. http://hdl.handle.net/1721.1/111042.
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Thesis: S.M., Massachusetts Institute of Technology, Department of Chemical Engineering, 2017.Cataloged from PDF version of thesis.
Includes bibliographical references (pages 75-85).
Incorporation of uranium recovery into wet phosphoric acid (WPA) processes can potentially supplement a significant portion of the world's uranium production and simultaneously benefit human health and environment by reducing radiological and toxic contamination of the phosphate fertilizer products. Liquid-liquid extraction as conventional uranium recovery methods applied in industrial suffers from various processing challenges, such as large consumption of combustible carriers, incomplete demulsification, interference with humic matters and crud formation. The aim of this thesis is to develop novel solid state gel-based materials suitable for recovery of uranium from industrial wet phosphoric acid. The materials developed can serve as the foundation of developing alternative processes to overcome limitations within liquid-liquid extraction for uranium recovery. Two types of materials -- magnetic organo-hydrogel and magnetic lyogel were developed and tested to be capable of extracting uranium selectively from the OCP phosphoric acid samples. The materials demonstrated sufficient structural stability, magnetic recoverability, similar uranium uptake performance as liquid-liquid extraction. Compared with magnetic organo-hydrogel, the lyogel exhibited reduced amount of extractant loss and better recyclability. Therefore, the magnetic lyogel can serve as the foundation on which novel uranium extraction processes to be designed in the future.
by Ran Chen.
S.M.
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Arlow, Antoinette. "Crystallisation aspects of the wet-process phosphoric acid industry." Pretoria : [s.n.], 2003. http://upetd.up.ac.za/thesis/available/etd-04152004-095501.
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Lizon, Tatiana Gallego. "Cadmium separation from phosphoric acid using the emulsion liquid membrane." Thesis, Imperial College London, 1998. http://hdl.handle.net/10044/1/7634.
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An emulsion liquid membrane (ELM) containing Cyanex 302 has been successfully used for the recovery of cadmium from synthetic phosphoric acid solutions containing 30% wt. P205. The ELM formulation was optimised for high extraction rate and stability. Cyanex 302, and a mixture of NaC1 (3M) and HC1 (1M), were selected from a set of possible reagents and stripping phases, following equilibrium and kinetic experiments in two-phase systems. Under chemical control the rate of Cd2 extraction was pseudo first order with respect to Cd2 and Cyanex 302 concentration. Arlacel C was found to be the most suitable surfactant for emulsion stability. The dependence of the ELM rate of Cd 2 extraction on the concentrations of cadmium, Cyanex 302, and surfactant, as well as on phase and treat ratio, and homogeniser and stirrer speed, was investigated. Cadmium extraction levels were found to be above 90% for most conditions. The influence of operating variables on emulsion swelling and rupture was also evaluated as a function of time. Swelling of the internal phase of the emulsion reached values greater than 50%, whilst emulsion rupture was below 2%. Emulsion globule size distributions in the stirred tank were measured for different impeller speeds and diameters, reagent concentrations, and emulsion hold-up, using an endoscope attached to a high-speed video camera. A correlation for globule size, accounting for swelling and rupture phenomena, changes in viscosity and hold-up, was proposed and found to be in good agreement with experimental results. This allowed the effect of the stirring speed on the specific interfacial area and the mass transfer coefficient to be decoupled, and led to the conclusion that the overall rate of Cd 2 recovery was controlled by diffusional resistances in the continuous phase. A time- dependent model, and a quasi-steady state model were proposed for the extraction of cadmium with the ELM. Simulations with both models were found to be in good agreement with experimental results.
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Behbahani, Reza M. "Heat transfer and heat transfer fouling in phosphoric acid evaporators." Thesis, University of Surrey, 2003. http://epubs.surrey.ac.uk/842710/.
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The primary problem in concentrating phosphoric acid is due to fouling on the tube-side of the heat exchangers of the evaporators. Scaling on the heat transfer surfaces occurs because of high supersaturation of phosphoric acid liquor with respect to calcium sulfate. A review of the existing literature reveals that no information is available on heat transfer and on crystallisation fouling of phosphoric acid solutions. Solubility of calcium sulfate is very important with regards to the scaling problems in phosphoric acid concentration plants. Hence, the solubility of different calcium sulfate types in phosphoric acid solution was studied and their dependency on acid concentration and temperature were investigated. A large number of measurements of heat transfer coefficient for water and phosphoric acid solutions under forced convective, subcooled flow boiling and pool boiling conditions at different temperatures, flow velocities, heat fluxes and concentrations were performed. The results show that the modified Gnielinski and Petukhov and Popov con-elations fit the experimental results for forced convective heat transfer to phosphoric acid solutions better than the other correlations. The Chen model and associated correlations were found suitable for the prediction of subcooled flow boiling heat transfer coefficients for phosphoric acid solutions. Applying the actual temperature driving force (Tw-Ti) instead of (Tw-Tb), a theoretical model was proposed, which permits the prediction of pool boiling heat transfer coefficients of phosphoric acid solutions with good accuracy. A large number of fouling experiments were carried out at different flow velocities, surface temperatures and concentrations to determine the mechanisms, which control deposition process. After clarification of the effect of operational parameters on the deposition process, a mathematical model was developed for prediction of fouling resistance. The activation energy evaluated for the surface reaction of the deposit formation was found to be 56,829 J/mol. The predicted fouling resistances were compared with the experimental data. Quantitative and qualitative agreement for measured and predicted fouling rates, is good. Also, a kinetic model for crystallization fouling was developed, using the field data. The predictions of the suggested model are in good agreement with the plant operating data. Finally, a numerical model was developed for computer simulation of shell and tube heat exchangers. The agreement between the field data and the prediction of the model was very satisfactory.
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Pilditch, Stephen Robert. "Modelling high temperature phosphoric acid doped polymer electrolyte fuel cells." Thesis, University of Newcastle Upon Tyne, 2010. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.519580.
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Kaplan, Matthew Jon. "Chiral Phosphoric Acid-Catalyzed Acetalization and Iso-Pictet-Spengler Reactions." Scholar Commons, 2013. http://scholarcommons.usf.edu/etd/4515.
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The development of novel asymmetric reaction methodologies has been invaluable in both the academic and industrial world. In just 15 years, organocatalysis has provided a new means of developing asymmetric reaction methodologies using catalysts that are environmentally benign, relatively inexpensive, bench stable, and non-toxic. One development in organocatalysis that is important to our group in particular is chiral phosphoric acid-catalysis. BINOL-derived and VAPOL-derived phosphoric acids have proven to be excellent catalysts for a number of reactions.
The two projects I will discuss my efforts on are acetalization and iso-Pictet-Spengler reactions. These were projects that I performed during my first two years as a graduate student. The acetalization was particularly fascinating as only one literature report existed for the catalytic asymmetric variant of a reaction that makes such important compounds--O,O-acetals. The acetalization reaction proved to be a formidable opponent, and to this date no research report has been published documenting the intra-, or intermolecular catalytic asymmetric acetalization of vinyl ethers or the intermolecular catalytic asymmetric transacetalization.
The iso-Pictet-Spengler reaction is one that is interesting because exhaustive research has been conducted into the development of catalytic asymmetric Pictet-Spengler reactions, but at the time of my research, not a single catalytic asymmetric method existed to synthesize tetrahydro-γ-carbolines, the product of the iso-Pictet-Spengler reaction. Structurally, the tetrahydro-γ-carboline is isomeric to the tetrahydro-β-carboline, the product of the Pictet-Spengler reaction. They differ only in the position of nitrogen in the annulated product. This reaction seemed attractive to investigate, since independent elegant reports by Professors Benjamin List, Henk Hiemstra, and Darren Dixon documented the excellent control over enantioselectivity that chiral phosphoric acid have in the Pictet-Spengler reaction. Concurrent with the beginning stages of this project, Professor Eric Jacobsen reported the enantioselective thiourea-catalyzed iso-Pictet-Spengler reaction. The results were very good but not as great as the Pictet-Spengler work he pioneered. Around the time this report came out I commenced my reaction studies, and this thesis is the sum of just two projects I worked on. There were many more including halolactonization, VAPOL synthesis, chiral phosphoric acid synthesis, catalytic asymmetric hydroamination, and others.
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Badini, Sérgio Ricardo Garcia [UNESP]. "Estudo da passagem de diferentes concentrações de ácido fosfórico através da dentina e observação da morfologia dentinária pelo microscópio eletrônico de varredura." Universidade Estadual Paulista (UNESP), 1997. http://hdl.handle.net/11449/113962.
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000036234.pdf: 4116221 bytes, checksum: 868e565d3f58d838039c7a0ba8c15bda (MD5)A finalidade deste trabalho foi verificar a passagem do ácido fosfórico em diferentes concentrações em dentina profunda, situado a 0,3mm da câmara pulpar, e observar as• alterações morfológicas da dentina pelo MEV. Setenta e dois corpos de prova, molares e pré-molares humanos hígidos, foram utilizados para este trabalho onde foi exposta a dentina oclusal. Através da máquina especialmente elaborada para o corte dos dentes, foi cortada a dentina deixando-a com espessura de 0,3 mm acima do corno pulpar. Os dentes foram aleatoriamente divididos em seis grupos de dez dentes cada: grupo 1 - controle ( sem tratamento ácido); grupo 2- ácido fosfórico a 10% sem sílica; grupo 3- ácido fosfórico a 32% sem sílica; grupo 4 - ácido fosfórico à 35% com sílica; grupo 5 – ácido fosfórico a 3 7% sem sílica e grupo 6 - ácido fosfórico a 50% líquido. Foi alojado na câmara pulpar dos corpos de prova, um papel de tornassol que atapetasse toda esta câmara, a fim de que quando aplicado o ácido fosfórico nas suas diferentes concentrações, pudéssemos avaliar a passagem mesmo. Cada concentração do ácido foi aplicada por quinze segundos e lavadas com spray água/ar. Observamos que: a) não houve a passagem do ácido fosfórico através da dentina com as diferentes concentrações estudadas; b) o ácido fosfórico a 10% sem sílica em corte transversal,demonstrou abertura parcial dos túbulos dentinários; c) o ácido fosfórico a 32% sem sílica, 35% com sílica, 37% sem sílica e 50% líquido demonstraram alterações morfológicas semelhantes; d) houve remoção preferencial da dentina peritubular; e) a sílica contida no ácido fosfórico a 35% não foi totalmente removida após abundantes lavagens
The purpose of this study was to verify acid penetration of phosphoric acid at variable concentrations, into deep dentin, located at 0,3 mm from the pulp chamber, and a.tso observe dentin morphological changes with S.E.M. Occlusal dentin of human sound molars and premolars was exposed totaling 72 specimens. A special designed device was used to section teeth, obtaining 0.3 mm of remaining dentin over pulp horns. Teeth were randomly assigned to six groups with ten teeth each: group 1 - Control (no acid conditioning); group 2 - 10 % phosphoric acid: group 3 - 32 % phosphoric acid; group 4 - 35 % phosphoric acid with silica; group 5 - 37 % phosphoric acid; group 6 - 50 % phosphoric acid solution. A pH indicating paper was placed on pulp chamber walls in order to verify acid penetration of acid etchants. Each etchant was applied for 15 seconds, spray rinsed and air dried Conclusions: a) no acid penetration occurred through dentin; b) dentin tubules were partially open in crosscut 10 % phosphoric acid specimens; c) similar morphological changes were found for 50 % solution, 37 %, 35 % and 32 % phosphoric acid groups; d) most structural removal occurred at peritubular dentin; e) silica from 35% acid gel was not completely removed from dentin surface after thorough rinsing.
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James, Keith Edward. "The Effects of Phosphonic Acids in Dye-Sensitized Solar Cells." PDXScholar, 2016. http://pdxscholar.library.pdx.edu/open_access_etds/2951.
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Novel methods for the construction of dye-sensitized solar cells (DSSCs) were developed. A thin dense underlayer of TiO2 was applied on fluorine-doped tin oxide (FTO) glass using as a precursor Tyzor AA-105. Subsequently a mesoporous film of P-25 TiO2 was applied by spreading a suspension uniformly over the surface of the underlayer and allowing the plate to slowly dry while resting on a level surface. After sintering at 500° C slides were treated with TCPP as a sensitizing dye and assembled into DSSCs. A novel method was used to seal the cells; strips of Parafilm® were used as spacers between the electrodes and to secure the electrodes together. The cells were filled with a redox electrolyte and sealed by dipping into molten paraffin.
A series of phosphonic acids and one arsonic acid were employed as coadsorbates in DSSCs. The coadsorbates were found to compete for binding sites, resulting in lower levels of dye adsorption. The resulting loss of photocurrent was not linear with the reduction of dye loading, and in some cases photocurrent and efficiency were higher for cells with lower levels of dye loading.
Electrodes were treated with coadsorbates by procedures including pre-adsorption, simultaneous (sim-adsorption), and post-adsorption, using a range of concentrations and treatment times and a variety of solvents. Most cells were tested using an iodide-triiodide based electrolyte (I3I-1) but some cells were tested using electrolytes based on a Co(II)/Co(III) redox couple (CoBpy electrolytes). Phosphonic acid post-adsorbates increased the Voc of cells using CoBpy electrolytes but caused a decrease in the Voc of cells using I3I-1 electrolyte. Phosphonic acids as sim-adsorbates resulted in a significant increase in efficiency and Jsc, and they show promise as a treatment for TCPP DSSCs.
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Psofogiannakis, George. "A mathematical model for a direct propane phosphoric acid fuel cell." Thesis, University of Ottawa (Canada), 2003. http://hdl.handle.net/10393/26424.
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In direct hydrocarbon fuel cells, a hydrocarbon fuel is oxidised in the anode electrode. This thesis presents a mathematical model to predict the performance of a unit cell that utilises propane as the fuel, oxygen as the oxidant, phosphoric acid as the electrolyte, and platinum as the catalyst, supported on porous carbon electrodes. The phenomena considered include the electrochemical reactions of propane oxidation and oxygen reduction on platinum, the diffusion of the gases in gas-filled electrode pores, the dissolution and diffusion of dissolved gases in liquid-filled electrode pores as well as ionic conduction of protons. The model was based on the multi-layered physical structure of a modern unit fuel cell.
The model was first applied to a phosphoric acid fuel cell cathode electrode.
Subsequently, the model was applied to a direct propane-oxygen cell. (Abstract shortened by UMI.)
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Booker, Nicholas Anthony. "Removal of cadmium from wet process phosphoric acid by cation exchange." Thesis, Imperial College London, 1989. http://hdl.handle.net/10044/1/47365.
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Luschtinetz, Regina. "Theoretical studies towards a ferroelectric organic field-effect transistor based on functional thiophene molecules." Doctoral thesis, Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2013. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-102735.
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Thin-film organic field effect transistors (OFETs) have attracted growing interest in recent years due to their promising electrical, optical and mechanical properties. Especially, oligothiophenes and their derivates are candidates with good prospects for application as the organic semiconducting material in such devices. They possess an extended, polarisable aromatic π-electron system that promotes a high structural arrangement of the molecules. The charge transport in the organic film is realised in the direction perpendicular to the plane of the thiophene rings via a hopping transport mechanism. Thus, a good π-π-overlap and a consequent stacking of the thiophene molecules in the film perpendicular to the gate substrate is essential to achieve excellent electric properties such as high charge carrier mobilities and low resistive losses.
The highly polarisable thiophene-based molecules are also very attractive materials that are potentially applicable as the field-sensitive organic semiconducting component of a ferroelectric OFET device. In such a device, the dielectric gate element of a conventional OFET setup is substituted by a ferroelectric substrate. The electric field that is induced by the polarisation of the ferroelectric material serves as gate field and controlls the charge injection and charge density inside the device.
In this thesis, thiophene-based molecules are investigated in detail with respect to their application as field-sensitive organic semiconducting component in a ferroelectric OFET device employing quantum-chemical ab initio and DFT-based methods. We demonstrate that the phosphonic acids can bind the organic molecules to the dielectric or ferroelectric material and well-anchored, robust self-assembled monolayers are formed. Furthermore, special focus is put on the influence of the intermolecular interactions among the organic molecules on the technologically relevant structural and electronic properties. It is found that the CN···HC hydrogen bond link the molecules into extended ribbons, but the π-π-stacking-stacking interaction is the main driving force in the self-assembly of the molecules. We also establish in detail the influence of the electric field on the phosphonic acid anchoring molecule and some quarterthiophene derivates.
For the latter, the strongest field-sensitivity is obtained for an external electric field aligned parallel to the extension of the thiophene framework. Hence, they are suitable to act as the field-sensitive organic components in devices that take advantage of a band-gap engineering. Moreover, the present results emphasise the importance of the adsorption morphology of the molecules in the film in a π-stacked fashion with their longitudinal axis oriented parallel to the (orthonormal) electric field induced by the ferroelectric substrate.
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Pienaar, Danie. "Synthetic applications of bicyclic phosphoric triamides." Diss., Pretoria : [s.n.], 2000. http://upetd.up.ac.za/thesis/available/etd-11172006-092708/.
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Liang, Tao. "Chiral Phosphoric Acids and Alkaline Earth Metal Phosphates Chemistry." Thesis, University of South Florida, 2014. http://pqdtopen.proquest.com/#viewpdf?dispub=3632228.
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Asymmetric synthesis and catalysis is one of the leading research areas in chemistry society, for its versatility and efficiency in obtaining chiral molecules that found the vast majority in natural active compounds and synthetic drugs. Developing asymmetric catalytic methodology is at the frontier in both industrial and academic research laboratories. Enantioselective organocatalysis has emerged as a powerful synthetic tool that is complementary to metal-catalyzed transformations. The development of chiral phosphoric acid and metal phosphate as catalysts has been a breakthrough in recent years. Chiral phosphoric acids have been shown to be powerful catalysts in many organic transformations. Moreover, chiral metal phosphates, which formed by simply replacing the proton in phosphoric acid with metals, have introduced new catalytic activations and broaden the scope of phosphoric acids. This thesis details new highly enantioselective chiral phosphoric acid-catalyzed Pinacol rearrangement and robust alkaline phosphates catalytic system, which utilizes novel carbonyl activation.
The Pinacol rearrangement has long been known to be difficult to control in terms of regioselectivity and stereoselectivity. The initial studies found that indolyl-diol compounds can be treated with chiral phosphoric acids to afford the Pinacol rearrangement with high regio- and enantioselectivity. Over 16 chiral phosphoric acids were screened, and it was found an H8-BINOL-phosphoric acid variant with 1-naphthyl groups at 3 and 3' position was the excellent catalyst. This asymmetric transformation is tolerant toward variety of substituents both on the indole ring and migrating groups.
During the study, it was found that different ways to generate the catalyst had critical effect on this catalytic transformation. Only those phosphoric acids washed with HCl after column chromatography afforded the rearrangement products with high enantioselectivity. And those without treating with HCl were found contaminated by alkaline metals. These "contamination" catalysts were also found active with carbonyl activations.
A highly enantioselective catalytic hetero-Diels-Alder reaction of alpha-keto esters has been developed with chiral alkaline metal phosphates. A calcium 1-naphthyl-BINOL phosphate was found to be the optimum catalyst. A large range of alpha-keto esters as well as isatins can be applied in this alkaline phosphates catalytic system with high efficiency and selectivity. The structure of the catalyst is detailed for the first time by X-ray crystal structure analysis. A proposed Transition state model is provided based on the catalyst crystal structure and Raman spectroscopy analysis.
This methodology was further developed with an asymmetric Mukaiyama-Michael addition of beta,gamma-unsaturated alpha-keto ester. The best catalyst was found to be a magnesium chiral phosphate. And the transformation was found capable of tolerating a wide variety of beta,gamma-unsaturated alpha-keto esters.
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Tharp, Ronald S. "Fabrication of carbon-aerogel electrodes for use in phosphoric acid fuel cells." Thesis, Massachusetts Institute of Technology, 2005. http://hdl.handle.net/1721.1/32962.
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Thesis (S.B.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 2005.Includes bibliographical references (leaf 47).
An experiment was done to determine the ability to fabricate carbon aerogel electrodes for use in a phosphoric acid fuel cell (PAFC). It was found that the use of a 25% solution of the surfactant Cetyltrimethylammonium chloride (CTAC) in water resulted in the creation of micelle within the pores of the organic aerogel. The micelle allowed the aerogel to be air dried while maintaining the desired pore composition. Further testing also showed that the resulting carbon aerogels had a specific ionic conductivity greater than that of a commercial porous carbon electrode Work was done to explore the use of the DRIE method to create a silicone die for the fabrication of a carbon aerogel electrode. It was found that a die could be created but had to undergo 0₂ plasma treatment in order to improve the wetting properties of the die. The resulting electrode was found to be very brittle at a thickness of 200 [mu]m or less, but responded well to being electroplated with platinum through the use of a platinum salt and a non-ionic surfactant gel.
by Ronald S. Tharp.
S.B.
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Ma, Yulin. "The Fundamental Studies of Polybenzimidazole/Phosphoric Acid Polymer Electrolyte for Fuel Cells." Case Western Reserve University School of Graduate Studies / OhioLINK, 2004. http://rave.ohiolink.edu/etdc/view?acc_num=case1089835902.
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Herocatty, Chen Po Cheng, and 陳博正. "Hybridized Resins Comprised Phosphonic Acid." Thesis, 2002. http://ndltd.ncl.edu.tw/handle/87247852484560621015.
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碩士淡江大學
化學學系
90
The thesis is based on corrosion protection by organic coatings. To synthesize the phosphorus-containing monomer (HEMAPOH) is the first step. The reactants are 2-hydroxyl ethyl mathacrylate (2-HEMA) and phosphorus pentoxide (P2O5), and the product is the phosphorus-containing monomer (HEMAPOH). Then, next step is to prepare the uv-curable epoxy resin. The epoxy prepolymer and acrylic acid are the starting materials for preparation of uv-curable epoxy resin. And next, there are three methods to prepare the coatings. The first is that the phosphorus-containing monomer (HEMAPOH) reacts with the epoxy prepolymer (the –OH groups on the HEMAPOH attacks to the epoxy rings on the epoxy prepolymer). The second is that uv-curable epoxy resin reacts with the phosphorus pentoxide. And the last is that the use of the uv light to cure the mixture of phosphorus-containing monomer and uv-curable epoxy resin. FT-IR, 1H-NMR, 13C-NMR and 31P-NMR is used to confirm the phosphorus-containing monomers. The thermal property of organic thin films are determined by the TGA (thermogravimetric analysis). Other physical properties, such as gel content, solvent swollen and water absorption, are also determined by suitable methods. The salt-fog test or electrochemical impedance spectroscopy (EIS) is used for the corrosion protection test.
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Tamber, Harinder. "Synthesis and characterization of phosphonate ester and phosphonic acid containing polymers and blends." 1997. http://catalog.hathitrust.org/api/volumes/oclc/47769873.html.
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Thesis (Ph. D.)--State University of New York. College of Environmental Science and Forestry, Syracuse, 1997.eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references.
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Hsu, Wei-Ling, and 徐暐怜. "Synthesis and Characterization of Polymerized (3-Aminophenyl)phosphonic Acid." Thesis, 2018. http://ndltd.ncl.edu.tw/handle/3qn63c.
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碩士國立清華大學
工程與系統科學系
106
At present, the self-doped polyaniline bear sulfonic, boronic and carboxylic groups, but bearing phosphonic group is rare in the study. The phosphonic acid functional group as the protonic acid radical of the self-doped polyanilines, it does not only show enough acidity for doping but also is a dibasic acid. The first acid radical is used to internal-doping in the polyaniline backbone, and the second acid radical would provide features, such as forming salt while keeping the doping state. In 2014, the Japanese study teams reported the studies of the self-doped polyaniline bearing phosphonic acid. The materials they used in the subsequent analysis showed good thermal stability, high transparency, polaron delocalization and self-doped effects. But there are not perfect studies in bearing phosphonic acid polyaniline area, therefore, there is still looking forward to improving performance and developing usability in the future. In this study, we try to use bearing phosphonic acid aniline (3-aminophenyl phosphonic acid) as the monomer and use the chemical oxidative polymerization with the various experimental parameters. Then, analyze the surface morphology, molecular structure, redox level and protonation level. Proved via UV-visible spectra and FTIR spectra, poly(3-aminophenyl) phosphonic acid similar to polyaniline backbone. The polymers can form the porous structure in the morphology by adding the initiator. For the proton exchange materials, increasing the surface area can effectively increase the proton transfer pathways. In addition, adding the initiator increase the degree of spins delocalization and protonation level effectively. The degree of protonation level increased from 20.26-37.64 (%) to 44.04-72.37 (%) (The oxidant is APS), 12.34-14.43 (%) increased to 14.05-19.35 (%) (The oxidant is K2S2O8) and 1.60-16.02 (%) increased to 10.57-30.26 (%) (The oxidant is H2O2). The redox level of the poly(3-aminophenyl phosphonic acid) can be controlled by the choice of oxidant. When using K2S2O8 as the oxidant, the average redox level is about 1.54, that is a relatively high level of oxidation. Whereas H2O2 is about 0.61, that is a high level of reduction. However, regardless of which oxidant is used, the polymers all have -N+- protonated structures, the binding energy ~401eV. Finally, the experiment progress found that poly3-aminophenyl phosphonic acid has spins delocalization effect. When using AP as the initiator, the A/B ratio tends to 1 have an optimum spin symmetry and a high degree of electron delocalization. Poly(3-aminophenyl phosphonic acid) is non-conductive, due to the acid group of the chemical structure has an interaction with the polyaniline backbone. Based on the current experimental results, poly(3-aminophenyl phosphonic acid) is a porous material that does not have electron conductivity. It can be known from the literatures that the phosphonic acid functional group can serve as the proton-donating and proton-accepting, so the polymer is proton conductivity. Therefore, it is expected to become a proton exchange material or an organic spintronic material.
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Chou, Shih-Chi, and 周詩綺. "Synthesis and properties of novel phosphonic acid containing-poly(alkylthiophene)/TiO2 hybrid materials." Thesis, 2006. http://ndltd.ncl.edu.tw/handle/24663407670749617578.
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碩士國立臺灣大學
高分子科學與工程學研究所
94
Polythiophenes have been widely used as photo-sensitizer and electron donor materials in polymer solar cells, because of their excellent optoelectronic properties and high charge-carrier mobility. However, the inherent incompatibility of organic polymers and inorganic particles frequently causes severe phase separation upon physical mixing, thus leading to poor photo-induced charge transfer efficiency. In this study, a series of novel polythiophene-TiO2 hybrid materials were synthesized by the sol-gel reaction of titanium alkoxide precursor in the presence of phosphonic acid-containing poly(3-hexylthiophene) to increase the interactions between TiO2 particles and conjugated polymer chains. 2,5-Dibromo-3-(ω-bromoalkyl)thiophenes bearing different chain-lengths of alkyl side groups were synthesized by reacting 3-bromothiophene with 1,ω-dibromoalkane, followed by the bromination with NBS. Then, the terminal bromide group on thiophene monomer was converted to the phosphonate moiety by reacting with P(OEt)3 via the Michaelis-Arbuzov rearrangement. Finally, the phosphonate-containing regioregular polythiophenes were synthesized by the McCullough method using 2,5-dibromo-3-hexylthiophene and 2,5-dibromo-3-(ω- alkylphosphonate)thiophene as monomers. The chemical structures of monomers and polymers were characterized using 1H NMR and 31P NMR analyses. GPC was employed to investigate the molecular weight characteristics of polymers. Polythiophene-TiO2 hybrid materials were prepared by the in-situ sol-gel reaction of titanium isopropoxide in the CHCl3 solution of polythiophene or phosphonate-bearing polythiophene. The bonding formation between phosphonic acid and TiO2 were confirmed by the FT-IR and solid state 31P NMR spectra of hybrids. Both SEM and TEM micrographs demonstrated that the presence of phosphonic-acid groups effectively prevents the macroscopic phase separation during the so-gel reaction, and showed that the size of TiO2 particles ranges from 5 to 20 nm. Moreover, the TEM pictures of hybrid materials revealed that TiO2 particles were better distributed inside the polythiophene matrix as the chain length of the alkyl side-arm increases to 10 carbons. Herein, a homogeneous and transparent hybrid material was successfully prepared, and the compatibility between TiO2 and polythiophene was greatly enhanced.
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Quan, Lan Tu. "Electrochemistry of cytochrome c on self-assembled phosphonic acid terminated alkanethiols on gold." 2004. http://www.lib.ncsu.edu/theses/available/etd-10292004-100531/unrestricted/etd.pdf.
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Lin, Ken, and 林肯. "Liquid crystal property and ion conductivity study of phosphonic acid functionalize imidazolium salts." Thesis, 2013. http://ndltd.ncl.edu.tw/handle/82350728583841785117.
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Faßbender, Birgit [Verfasser]. "Solid-state NMR investigation of phosphonic acid based proton conducting materials / von Birgit Faßbender." 2009. http://d-nb.info/1000760863/34.
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Kao, Chia-Chun, and 高佳駿. "Synthesis and Characterization of Mesoporous Silicas With Benzen bridging, amine and phosphonic acid groups." Thesis, 2009. http://ndltd.ncl.edu.tw/handle/57854953417185928798.
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碩士國立中央大學
化學研究所
97
The thesis is divided into three parts. Studies on functionalization of mesoporous materials. In part one, the mesoporous silica SBA-1 (cubic Pm3n symmetry) functionalized with phenyl groups were synthesized via co-condensation of 1,4-bis(triethoxysilyl)benzene (BTEB) and tetraethoxysilane (TEOS) under acidic conditions using cetyltriethylammonium bromide (CTEABr) as a structure-directing agent. By optimizing the synthesis composition, the resulting materials exhibited much higher surface areas (up to 1210 m2/g) and larger pore volumes (up to 0.64 cm3/g) as compared to the previous analogue, which only exhibited a surface area of 381 cm2/g and a pore volume of 0.11 cm3/g. Two dimensional (2D) 29Si{1H} heteronuclear correlation (HETCOR) NMR spectra, acquired as a function of contact time, provided direct spectroscopic evidence that a single mesophase with various Q (from TEOS) and T silicon species (from BTEB) located randomly within the pore walls via co-condensation of BTEB and TEOS at a molecular level. Such information is often not achievable by other characterization techniques In part two, well-ordered cubic mesoporous silica SBA-1 functionalized with amino functional groups have been synthesized via co-condensation of tetraethoxysilane (TEOS), (3-aminopropyl)trimethoxysilane (APTMS) templated by cetyltriethylammonium bromide (CTEABr), under strongly acidic condition by using chlorosulfonic acid as an acidic medium. The materials thus obtained were characterized by a variety of techniques including X-ray diffraction (XRD), solid state 13C and 29Si NMR spectroscopy, thermogravimetric analysis (TGA) and nitrogen sorption measurements. Direct NMR evidence for the amine functional groups in close proximity to the Q3 SiOH species in amino-functionalized mesoporous silica SBA-1 is provided by two-dimensional 29Si{1H} HETCOR-based NMR. In the third part, highly ordered SBA-15 mesoporous silica contains phosphonic acid groups are synthesized via co-condensation of tetraethylorthosilicate (TEOS) and diethylphosphatoethyltriethoxysilane (PETES) using Pluronic 123 (P123) as a structure-directing agent under acidic conditions. The presence of functional group in th resultant material are confirmed by 29Si{31P} REDOR NMR study.
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Ming-chingChan and 詹明靜. "Carboxyl and phosphonic acid-containing copolymers for surface modification of titanium: synthesis and characterization." Thesis, 2014. http://ndltd.ncl.edu.tw/handle/31551677581676936659.
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碩士國立成功大學
化學工程學系
102
Because titanium-based materials have relatively good biocompatibility, well mechanical, corrosion resistance and non-magnetic properties, it has been widely used in the field of biomaterial medical implants to replace tradition material, stainless steel and cobalt alloy etc. However, owing to the problems with poor hemo-compatibility, anti-biofouling ability and long healing time, they have limited the application of titanium-based materials on hard tissue replacement, osteosynthesis devices, heart valves and vascular stents. The object of this investigation was to develop a novel surface modification strategy for titanium-based material to improve biocompatibility and osseointegration. We synthesized two monomers that one with carboxylic acid group which is biocompatibility and well-adhesion for cell, called 6-acryloyloxyhexanoic acid (AHA), the other with phosphonates group which was an anchor group for metal surface, called 11-Acryloyloxy undecyl phosphonic acid (AcrUPA), and their co-polymer (AxHy). These copolymers should be able to bind on the titanium surface to form a well biocompatibility film. We hope this ideal could be a new way to improve the titanium-based medical implants. The properties of the copolymers were characterized with nuclear magnetic resonance spectroscopy (NMR), gel permeation chromatography (GPC) and thermo-gravimetric analysis (TGA). We applied the spin coating to form a uniform film on the titanium surface after the copolymers were successful synthesized. Then the modified titanium substrates were heated for forming the covalent bond between phosphonic acid and titanium substrate. Finally, the modified titanium substrate surface were tested by static water contact angle measurement, scanning electron microscope (SEM), atomic force microscopy (AFM) and X-ray photoelectron spectroscopy (XPS) to learn the surface hydrophilic/hydrophobic, films stability, surface roughness and surface atomic ratio percent. We found that the copolymer molecular weight was not high enough. We speculated that it was resulted from the hydrophilic/ hydrophobic difference of the monomers and the AHA molecular tendency to self-aggregation. Thought the molecular was not high enough, we could control the condition of spin coating to produce well quality and stable films that was tested by several surface analyses. In the future, we will test cell response on titanium substrate surface with a which different monomer ratio copolymer modified. And then, we will understand which one promoted the biocompatibility most.