Дисертації з теми "Rafut"
Оформте джерело за APA, MLA, Chicago, Harvard та іншими стилями
Ознайомтеся з топ-50 дисертацій для дослідження на тему "Rafut".
Біля кожної праці в переліку літератури доступна кнопка «Додати до бібліографії». Скористайтеся нею – і ми автоматично оформимо бібліографічне посилання на обрану працю в потрібному вам стилі цитування: APA, MLA, «Гарвард», «Чикаго», «Ванкувер» тощо.
Також ви можете завантажити повний текст наукової публікації у форматі «.pdf» та прочитати онлайн анотацію до роботи, якщо відповідні параметри наявні в метаданих.
Переглядайте дисертації для різних дисциплін та оформлюйте правильно вашу бібліографію.
Fleet, Reda. "RAFT mediated polysaccharide copolymers." Thesis, Link to the online version, 2006. http://hdl.handle.net/10019/1025.
Повний текст джерелаSuwattana, Siripan. "Biodegradable polymers via RAFT." Thesis, University of Leeds, 2011. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.549765.
Повний текст джерелаAntus, Joakim. "Reaching Consensus Using Raft." Thesis, Uppsala universitet, Institutionen för informationsteknologi, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-301332.
Повний текст джерелаZong, Mengmeng. "RAFT polymerisation in supercritical CO2." Thesis, University of Nottingham, 2010. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.537644.
Повний текст джерелаNozari, Samira. "Towards understanding RAFT aqueous heterophase polymerization." Phd thesis, Universität Potsdam, 2005. http://opus.kobv.de/ubp/volltexte/2005/580/.
Повний текст джерелаThe degradation of the RAFT agent by addition of KPS initiator revealed unambigueous evidence on the mechanism of entry in heterophase polymerization. These results showed that even extremely hydrophilic primary radicals, such as sulfate ion radical stemming from the KPS initiator, can enter the polymer particles without necessarily having propagated and reached a certain chain length. Moreover, these results recommend the employment of azo-initiators instead of persulfates for the application in seeded heterophase polymerization with RAFT agents.
The significant slower rate of transportation of the RAFT agent to the polymer particles when its solvent (styrene) was replaced with a more hydrophilic monomer (methyl methacrylate) lead to the conclusion that a complicated cooperative and competitive interplay of solubility parameters and interaction parameter with the particles exist, determining an effective transportation of the organic molecules to the polymer particles through the aqueous phase. The choice of proper solutions of even the most hydrophobic organic molecules can provide the opportunity of their sorption into the polymer particles. Examples to support this idea were given by loading the extremely stiff fluorescent molecule, pentacene, and very hydrophobic dye, Sudan IV, into the polymer particles.
Finally, the first application of RAFT at room temperature heterophase polymerization is reported. The results show that the RAFT process is effective at ambient temperature; however, the rate of fragmentation is significantly slower. The elevation of the reaction temperature in the presence of the RAFT agent resulted in faster polymerization and higher molar mass, suggesting that the fragmentation rate coefficient and its dependence on the temperature is responsible for the observed retardation.
Um neue Materialien mit außergewöhnlichen Eigenschaften zu erstellen, muss man in der Lage sein, die Struktur der Moleküle zu kontrollieren, aus denen die Materialien bestehen. Für das Maßschneidern solcher neuer Eigenschaften besitzen Polymere ein großes Potenzial: Dies sind sehr lange Moleküle, die aus einer großen Zahl von kleineren Einheiten aufgebaut sind. Proteine und DNS sind Beispiele für natürliche Polymere; Plastik und Gummi sind Beispiele für künstliche Polymere. Letztere werden üblicherweise durch das Zusammenfügen einer Reihe von kleineren Molekülen, den Monomeren, hergestellt. Schon lange versuchen Wissenschaftler, die Anordnung, Anzahl und Art dieser Monomere zu kontrollieren, die sich in der Struktur der Polymermoleküle widerspiegeln. Die gebräuchlichste Methode zur kommerziellen Produktion von Polymeren ist die so genannte freie radikalische Polymerisation. Die Strukturkontrolle durch diese Methode ist jedoch relativ schwierig und wurde maßgeblich erst im letzten Jahrzehnt entwickelt. Trotz der Existenz einiger effektiver Kontrollmethoden ist ihre industrielle Anwendung bislang sehr beschränkt, weil sie nicht für die Emulsionspolymerisation verwendbar sind. Die Emulsionspolymerisation ist die gängigste Technik in der industriellen Produktion von Polymeren. Es handelt sich dabei um ein vergleichsweise umweltfreundliches Verfahren, denn es werden keine organischen Lösungsmittel verwendet. Stattdessen dient Wasser als Lösungsmittel, in dem die Polymere in Form von kleinen, fein verteilten Partikeln vorliegen. In der Natur kommt dieses Prinzip beispielsweise in Pflanzen bei der Bildung von Kautschuk - allgemein als Latex bezeichnet - vor. Schließlich ist die Emulsionspolymerisation einfach durchzuführen: Das Produkt ist in vielen Fällen gebrauchsfertig, und es gibt viele technische Vorteile im Vergleich zu anderen Herstellungsprozessen.
Doch bevor die Probleme beim Einsatz von Kontrollmethoden in der Emulsionspolymerisation gelöst werden können, müssen erst ihre Ursachen geklärt werden. Dies ist eine unverzichtbare Vorraussetzung zum Übertragen von Forschungsergebnissen auf das tägliche Leben.
Ziel dieser Arbeit ist die Untersuchung der Probleme, die für die kontrollierte radikalische Polymerisation in Emulsion von Bedeutung sind. Die wichtigste Fragestellung in der Emulsionspolymerisation zielt auf die Löslichkeit der Reaktionskomponenten in den verschiedenen Phasen, wie z.B. in Wasser oder in den Polymerpartikeln. Die Kontrollmethode der Wahl für diese Arbeit ist "Reversibler Additions-Fragmentierungs Transfer" (RAFT). Die RAFT-Methode ist die modernste Kontrollmethode, und sie ist für viele Reaktionsbedingungen und viele Arten von Monomeren anwendbar.
Gemici, Hesna. "Water soluble polymers by RAFT polymerisation." Thesis, University of Leeds, 2008. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.507717.
Повний текст джерелаBray, Caroline. "Aqueous RAFT polymerisation of acrylamide monomers." Thesis, University of Warwick, 2018. http://wrap.warwick.ac.uk/111296/.
Повний текст джерелаElnakat, Hala. "Regulation of Folate Receptor Raft Recycling." University of Toledo Health Science Campus / OhioLINK, 2007. http://rave.ohiolink.edu/etdc/view?acc_num=mco1174569209.
Повний текст джерелаRakut, Christian [Verfasser]. "Analyse der Wärmetransportmechanismen in thermischen Radialturbinen / Christian Rakut." Düren : Shaker, 2019. http://d-nb.info/1196487553/34.
Повний текст джерелаPflughaupt, Robin L. "In pursuit of RAFT-functional polyethylene : exploration of a novel class of Sn-RAFT agents and the preparation and application of RAFT-functional polyethylene-like poly(ω-pentadecalactone)". Thesis, University of Warwick, 2014. http://wrap.warwick.ac.uk/64038/.
Повний текст джерелаPeng, Wentao. "Binary Planet–Satellite Nanostructure Using RAFT Polymer." Doctoral thesis, Niedersächsische Staats- und Universitätsbibliothek Göttingen, 2020. http://hdl.handle.net/21.11130/00-1735-0000-0005-144A-2.
Повний текст джерелаBanaco, Joana Filipa das Neves. "Encapsulação de nanopartículas anisotrópicas por polimerização RAFT." Master's thesis, Universidade de Aveiro, 2013. http://hdl.handle.net/10773/12265.
Повний текст джерелаOs avanços tecnológicos recentes têm vindo a gerar um enorme interesse em novos materiais, desafiando a comunidade científica a focarem a sua atenção no desenvolvimento de novos métodos de síntese para a produção, por exemplo, de nanocompósitos. O objetivo deste trabalho consistiu na otimização do procedimento de encapsulação de nanopartículas anisotrópicas (NPs) recorrendo à polimerização em emulsão e ao mecanismo de polimerização controlada por reações reversíveis de adição-fragmentação de um agente de transferência de cadeia (RAFT). No sentido de se obter um filme de polímero em torno das partículas e minimizar a formação de polímero livre, foram efetuados estudos de adsorção de um agente RAFT macromolecular (MR) à superfície de nanofibras de Gd2O3:Eu3+revestidas com sílica não calcinada cujos resultados foram monitorizados por espectroscopia UV/VIS. Nestes estudos foram analisados dois parâmetros, o pH e o tempo de contacto adsorvato/adsorvente. Estes tiveram como principal objetivo a obtenção das isotérmicas de equilíbrio de adsorção a 25 ºC, as quais forneceram informação acerca da quantidade máxima de MR adsorvida. Através desta informação, foi possível inferir que os dois parâmetros analisados afetaram significativamente os resultados. Os dados experimentais foram modelados recorrendo a alguns modelos teóricos de adsorção verificando-se que tanto os modelos de Langmuir, como o de Freundlich se ajustam bem aos resultados obtidos. Numa segunda fase, foi estudada a encapsulação das nanofibras através da polimerização em emulsão via RAFT de metacrilato de metilo (MMA) e de acrilato de n-butilo (BA). Estas polimerizações foram efetuadas a pH 7, 5,5 e 3,5 (80 ºC), e com as condições ótimas provindas dos estudos de adsorção. Os látexes obtidos foram caracterizados por dispersão de luz dinâmica (DLS) e potencial zeta (ZP). Os látexes obtidos a pH 7 foram também caracterizados por microscopia eletrónica de varrimento em modo de transmissão (STEM). A conversão foi determinada por gravimetria. Os resultados obtidos por STEM confirmaram a encapsulação das nanopartículas assim como os valores obtidos de ZP. No entanto, os valores obtidos para a conversão de monómero foram apenas de 45%.
Recent technological advances have been the basis of increasing interest in the development of new materials, challenging the scientific community to focus their attention to devise new synthesis methods for the production of e.g. nanocomposites. The purpose to this work consists in the optimization of the procedure to encapsulate anisotropic nanoparticles(NPs), using the emulsion polymerization and the polymerization mechanism controlled by reversible addition-fragmentation of a chain transfer agent (RAFT). In order to obtain a polymer film surrounding the particles and minimize the formation of free polymer, the adsorption of a macromolecular RAFT agent (MR) onto the surface of Gd2O3:Eu3+coated with uncalcined silica was studied, where results were monitored by UV / VIS spectroscopy. This study analyzed two parameters: pH and contact time of adsorbant /adsorbent. The aim of this was to obtain the equilibrium adsorption isotherms at 25ºC, which provided information about the maximum amount of adsorbed MR. This information proved that the two analyzed parameters significantly affect the results. The best values were obtained at a pH of 5.5 and a contact time of 15 hours. The experimental data were adjusted to some theoretical models of adsorption and it was verified that the Langmuir and Freundlich models fit the obtained results. In a second stage of this work, the encapsulation of nanofibres by emulsion polymerization of methyl methacrylate (MMA) and n-butyl acrylate (BA) RAFT was studied. These polymerizations were carried out at pH 7, 5,5 and 3,5 (80 ºC), using the optimal conditions previously established from adsorption studies. The obtained latexes were characterized by dynamic light scattering (DLS) and zeta potential (ZP). The latexes obtained at pH 7 were also characterized by scanning transmission electron microscopy (STEM). The conversion was determined gravimetrically. The results obtained with STEM and ZP confirmed the encapsulation of nanoparticles. However, the value obtained for monomer conversion was low (45%).
Leswin, Joost Sieger Kaspar. "Particle Formation in RAFT-mediated Emulsion Polymerization." Thesis, The University of Sydney, 2007. http://hdl.handle.net/2123/2176.
Повний текст джерелаLeswin, Joost Sieger Kaspar. "Particle Formation in RAFT-mediated Emulsion Polymerization." University of Sydney, 2007. http://hdl.handle.net/2123/2176.
Повний текст джерелаParticle formation in RAFT-mediated emulsion polymerization has been studied using reaction calorimetry. By measuring the heat flow during controlled feed ab-initio emulsion polymerization in the presence of amphipathic RAFT agents, particle formation by self-assembly of these species could be observed. Two different monomer systems, i.e. styrene and n-butyl acrylate, and various degrees of hydrophobicity of the initial macro-RAFT agents have been studied and compared. The different macro-RAFT agents were synthesized by first forming a hydrophilic block of poly(acrylic acid) that would later on act as the electrosteric stabilizing group for the particles. Subsequently, different lengths of hydrophobic blocks were grown at the reactive end of the poly(acrylic acid) hydrophilic block via the RAFT-mediated controlled radical polymerization, either comprised of n-butyl acrylate or styrene. Two processes govern particle formation: adsorption of macro-RAFT agents onto growing particles and formation of new particles by initiation of micellar aggregates or by homogeneous nucleation. Competition between these processes could be observed when monomers with a relatively high (n-butyl acrylate) or low (styrene) propagation rate coefficient were used. A model describing particle formation has been developed and the results of model calculations are compared with experimental observations. Preliminary modeling results based on a set of reasonable physico-chemical parameters already showed good agreement with the experimental results. Most parameters used have been verified experimentally. The development of the molecular weight distribution of the macro-RAFT agents has been analyzed by different techniques. Quantification of the particle formation process by analytical techniques was difficult, but qualitative insights into the fundamental steps governing the nucleation process have been obtained. The amount of macro-RAFT agents initially involved in particle formation could be determined from the increase of molecular weight. The particle size distribution has been measured by capillary hydrodynamic fractionation, transmission electron microscopy and dynamic light scattering. From the data obtained from these particle-sizing techniques, the number of particles during the reaction could be monitored, leading to an accurate estimate for the particle formation time. Upon implementation of the experimental data obtained for the surface active macro-RAFT systems, the model demonstrated to be very sensitive towards the “headgroup” area of the macro-RAFT species. Three nucleation cases based on the initial surface activity of the macro-RAFT species in the aqueous phase are proposed to explain the deviations from the assumptions of the nucleation model. Even though the macro-RAFT species have a narrow molecular weight distribution, they are nevertheless made up of a distribution of block lengths of polystyrene upon a distribution of block lengths of poly(acrylic acid). The resulting differences in initial surface activity are the most probable reason for the observed differences between model calculations and experimental results for the nucleation time and particle size distribution of the final latex product. With the procedure described above, latexes have been synthesized without using conventional surfactants and the mechanisms involved in the particle formation for these systems have been elucidated. The results of this work enable production of latex systems with well defined molecular mass distributions and narrow particle size distributions. Furthermore, the technique based on the application of amphipathic RAFT agents is promising for the production of complex polymeric materials in emulsion polymerization on a technical scale.
GIRETTI, Daniela. "MODELLING OF PILED RAFT FOUNDATIONS IN SAND." Doctoral thesis, Università degli studi di Ferrara, 2010. http://hdl.handle.net/11392/2389285.
Повний текст джерелаNelson, Matthew D. "Lipid raft heterogeneity and dynamics in T lymphocytes." Click here for download, 2006. http://wwwlib.umi.com/cr/villanova/fullcit?p1432528.
Повний текст джерелаFischer, Thorsten. "Modelling of lipid raft formation in cell membranes." Thesis, University of Nottingham, 2010. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.546490.
Повний текст джерелаLuheshi, Yousef Bashir. "The fatigue characteristics of precast concrete raft units." Thesis, University of Newcastle Upon Tyne, 1997. http://hdl.handle.net/10443/1582.
Повний текст джерелаJohnson, Fiona Ann. "The physico-chemical characterisation of alginate raft systems." Thesis, University College London (University of London), 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.297175.
Повний текст джерелаHann, Monika. "Raft microdomains in myelin : an in vitro investigation." Thesis, Open University, 2007. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.446302.
Повний текст джерелаJeffrey, J. G. "Synthesis and chemistry of hexaosmium carbonyl 'raft' clusters." Thesis, University of Cambridge, 1985. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.355865.
Повний текст джерелаMorse, Charlotte. "Block copolymer nanoparticles prepared by RAFT aqueous polymerisation." Thesis, University of Sheffield, 2017. http://etheses.whiterose.ac.uk/19014/.
Повний текст джерелаCotanda, Santapau Maria José. "Amino-containing polymers for catalysis using RAFT polymerization." Thesis, University of Warwick, 2012. http://wrap.warwick.ac.uk/56272/.
Повний текст джерелаWilks, Thomas R. "Synthesis of DNA-polymer conjugates using RAFT polymerisation." Thesis, University of Warwick, 2013. http://wrap.warwick.ac.uk/58568/.
Повний текст джерелаChirowodza, Helen. "Polymer-clay nanocomposites prepared by RAFT-supported grafting." Thesis, Stellenbosch : Stellenbosch University, 2012. http://hdl.handle.net/10019.1/71914.
Повний текст джерелаENGLISH ABSTRACT: In materials chemistry, surface-initiated reversible deactivation radical polymerisation (SI-RDRP) has emerged as one of the most versatile routes to synthesising inorganic/organic hybrid materials consisting of well-defined polymers. The resultant materials often exhibit a remarkable improvement in bulk material properties even after the addition of very small amounts of inorganic modifiers like clay. A novel cationic reversible addition–fragmentation chain transfer (RAFT) agent with the dual purpose of modifying the surface of Laponite clay and controlling the polymerisation of monomer therefrom, was designed and synthesised. Its efficiency to control the polymerisation of styrene was evaluated and confirmed through investigating the molar mass evolution and chain-end functionality. The surface of Laponite clay was modified with the cationic chain transfer agent (CTA) via ion exchange and polymerisation performed in the presence of a free non-functionalised CTA. The addition of the non-functionalised CTA gave an evenly distributed CTA concentration and allowed the simultaneous growth of surface-attached and free polystyrene (PS). Further analysis of the free and grafted PS using analytical techniques developed and published during the course of this study, indicated that the free and grafted PS chains were undergoing different polymerisation mechanisms. For the second monomer system investigated n-butyl acrylate, it was apparent that the molar mass targeted and the monomer conversions attained had a significant influence on the simultaneous growth of the free and grafted polymer chains. Additional analysis of the grafted polymer chains indicated that secondary reactions dominated in the polymerisation of the surface-attached polymer chains. A new approach to separating the inorganic/organic hybrid materials into their various components using asymmetrical flow field-flow fractionation (AF4) was described. The results obtained not only gave an indication of the success of the in situ polymerisation reaction, but also provided information on the morphology of the material. Thermogravimetric analysis (TGA) was carried out on the polymer-clay nanocomposite samples. The results showed that by adding as little as 3 wt-% of clay to the polymer matrix, there was a remarkable improvement in the thermal stability.
AFRIKAANSE OPSOMMING: Oppervlakgeïnisieerde omkeerbare deaktiveringsradikaalpolimerisasie (SI-RDRP) is een van die veelsydigste roetes om anorganiese/organiese hibriedmateriale (wat bestaan uit goed-gedefinieerde polimere) te sintetiseer. Die produk toon dikwels ʼn merkwaardige verbetering in die makroskopiese eienskappe – selfs na die toevoeging van klein hoeveelhede anorganiese modifiseerders soos klei. ʼn Nuwe kationiese omkeerbare addisie-fragmentasie kettingoordrag (RAFT) middel met die tweeledige doel om die modifisering van die oppervlak van Laponite klei en die beheer van die polimerisasie van die monomeer daarvan, is ontwerp en gesintetiseer. Die klei se doeltreffendheid om die polimerisasie van stireen te beheer is geëvalueer en bevestig deur die molêre massa en die funksionele groepe aan die einde van die ketting te ondersoek. Die oppervlak van Laponite klei is gemodifiseer met die kationiese kettingoordragmiddel (CTA) deur middel van ioonuitruiling en polimerisasie wat uitgevoer word in die teenwoordigheid van ʼn vrye nie-gefunksionaliseerde CTA. Die toevoeging van die nie-gefunksionaliseerde CTA het ʼn eweredig-verspreide konsentrasie CTA teweeggebring en die gelyktydige groei van oppervlak-gebonde en vry polistireen (PS) toegelaat. Verdere ontleding van die vrye- en geënte PS met behulp van analitiese tegnieke wat ontwikkel en gepubliseer is gedurende die verloop van hierdie studie, het aangedui dat die vry- en geënte PS-kettings verskillende polimerisasiemeganismes ondergaan. n-Butielakrilaat is in die tweede monomeer-stelsel ondersoek en dit was duidelik dat die molêre massa wat geteiken is en die geënte polimeerkettings. ʼn Nuwe benadering tot die skeiding van die anorganiese/organiese hibriedmateriale in hulle onderskeie komponente met behulp van asimmetriese vloeiveld-vloei fraksionering (AF4) is beskryf. Die resultate wat verkry is, het nie net 'n aanduiding gegee van die sukses van die in-situ polimerisasiereaksie nie, maar het ook inligting verskaf oor die morfologie van die materiaal. Termogravimetriese analise (TGA) is uitgevoer op die polimeer-klei nanosaamgestelde monsters. Die resultate het getoon dat daar 'n merkwaardige verbetering in die termiese stabiliteit was na die toevoeging van so min as 3 wt% klei by die polimeermatriks.
Bailly, Nathalie. "AB diblock copolymers via RAFT-mediated miniemulsion polymerization." Thesis, Stellenbosch : Stellenbosch University, 2008. http://hdl.handle.net/10019.1/2707.
Повний текст джерелаThe Reversible addition fragmentation chain transfer (RAFT) technique is a robust and versatile technique that enables the synthesis of polymers of controlled molecular weight and polydispersity. The application of the RAFT technique in heterogeneous aqueous media has attracted great interest in academics and industry due to it being more environmentally friendly, besides its other advantages. To date, the synthesis of well-defined high molecular weight polymers via the RAFT process under industrially relevant conditions still remains a challenge for polymer chemists. The study addresses the application of the RAFT process in heterogeneous media, namely in miniemulsion polymerization, for the synthesis of AB diblock copolymers of n-butyl methacrylate and styrene. AB diblock copolymers of high molecular weight were successfully prepared via a twostep method. In the first step, a dithiobenzoate monofunctional RAFT agent was used in bulk polymerization with the first monomer, n-butyl methacrylate. After the polymerization, the majority of the polymer chains contained the thiocarbonyl-thio RAFT agent functionality, which makes the chains potentially active for chain extension. The polymeric RAFT agent (also referred to as the starting block) obtained in the first step was chain extended in the second step, in miniemulsion, upon further addition of fresh initiator and the second monomer, styrene. The effects of the initiator/RAFT agent concentration ratio on the miniemulsion systems were investigated. The miniemulsion systems used for the high molecular weight AB diblock copolymers exhibited living features despite the high polydispersity indices. Kinetic results showed an increase in the rate of polymerization throughout the polymerization. Size exclusion chromatography (SEC) results indicated significant broadening in the molecular weight distributions and a steep increase in the polydispersity during the polymerization. It was concluded that the broad molecular weight distributions and steep increase in the polydispersity was not only related to the initiator concentration but possibly due to other factors such as inhomogeneity in the miniemulsion system and a transition in the kinetic behavior during the polymerization. Secondary particle formation emerged from kinetic data and transmission electron microscopy (TEM) results, but this were not supported by the SEC results. The effect of the use of a water-soluble initiator on the miniemulsion system was also investigated. Results indicated a similar behavioral pattern as observed in the AIBNinitiated systems, and not much improvement in terms of the molecular weight distributions and polydispersity was seen. The effect of the molecular weight of the diblock copolymers on the miniemulsion system was investigated. Poly(n-butyl methacrylate)-b-poly(styrene) diblock copolymers of lower molecular weight were synthesized via the two-step process. Kinetic results indicated a similar behavioral trend as to that of the high molecular weight diblock copolymers synthesized, however SEC chromatograms showed narrower molecular weight distributions and low polydispersity indices.
Bivigou, Koumba Achille Mayelle. "Design, synthesis and characterization of novel raft agents." Thesis, Stellenbosch : University of Stellenbosch, 2005. http://hdl.handle.net/10019.1/2992.
Повний текст джерелаThis thesis begins with the description of the preparation of thirteen dithioesters (of the form Z- (C=S)-S-R) which were characterized via Fourier-transform infrared spectroscopy (FT-IR), nuclear magnetic resonance spectroscopy (NMR) and ultraviolet spectroscopy (UV). The dithioesters were then used as reversible addition-fragmentation chain transfer (RAFT) mediating agents in the bulk polymerization of styrene, in order to observe differences in the kinetic behaviour of the polymerizations and, as a result, the efficiencies of the dithioesters in mediating the polymerizations.
Ng, Harald. "Distributed Consensus: Performance Comparison of Paxos and Raft." Thesis, KTH, Skolan för elektroteknik och datavetenskap (EECS), 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-281973.
Повний текст джерелаMed tillväxten av internet har distribuerade system blivit allt mer viktiga för att bygga mer tillgängliga och skalbara applikationer. Konsensus är ett funda- mentalt problem i distribuerade system där flera processer ska komma överens om samma föreslagna värde, samtidigt som partiella fel kan ske. Distribuerad konsensus kan appliceras till olika användningsomården som låstjänster, kon- figurationshanterare och distribuerade databaser.Två välkända konsensusalgoritmer för att bygga distribuerade loggar är Multi-Paxos och Raft. Multi-Paxos publicerades nästintill tre årtionden före Raft och blev populär. Men kritiker av Multi-Paxos anser att algoritmen är svår att förstå. Av denna anledning publicerades Raft med motivationen att vara en konsensusalgoritm som är enkel att förstå. Raft delar likheter med Leader- based Sequence Paxos, en praktisk version av Multi-Paxos. Dock skiljer sig algoritmerna i viktiga aspekter som leaderval och rekonfigurering.Befintliga arbeten jämför i huvudsak Multi-Paxos och Raft i teorin, men det saknas jämförelse av prestandan i praktiken. Av denna anledning har pro- totyper av Leader-based Sequence Paxos och Raft blivit designade och imple- menterade i denna avhandling. Dessa prototyper implementerades i program- meringsspråket Rust och message-passing ramverket Kompact, som sedan tes- tades i verkliga situationer för att jämföra Leader-based Sequence Paxos och Raft.Resultaten visar att Leader-based Sequence Paxos och Raft har liknande prestanda i geografiskt distribuerade sammanhang. Dock kan det oförutsäga- bara ledarvalet i Raft påverka prestandan avsevärt ifall den valde ledaren befin- ner sig på en oönskad plats. I våra experiment påverkade Raft ledarens plats den genomsnittliga kapaciteten med upp till 35%. Resultaten visar även att implementationsdetaljer kan ha en signifikant effekt på prestandan även i de delar där algoritmerna är liknande. Genom att sammanfoga meddelanden mer effektivt uppnådde Leader-based Sequence Paxos 17% högre genomsnittlig kapacitet än Raft.
Lagarde, Antoine. "Birth, life and death of a granular raft." Thesis, Sorbonne université, 2020. http://www.theses.fr/2020SORUS054.
Повний текст джерелаWe study the life of an axisymmetric monolayer of particles called a granular raft floating at an oil-water interface, from its formation to its sinking. We first look at the capillary interaction between a pair of beads, and generalize the result to a pair of granular rafts. The force strongly depends on the number of particles in each raft, a result that we understand by looking at the interfacial deformation each individual raft creates. Then, we explore the interaction between numerous granular rafts of different sizes randomly distributed. The aggregation is faster when the particles are initially more concentrated at the interface. The individual motion of each bead cannot be solved, but the overall clustering can be described statistically. The cluster-size distribution appears to answer to a self-similar evolution that we characterize. After that, we focus on the structural changes a granular raft can experience during its motion, and more precisely to its erosion. The cohesion of an entire raft is far higher than expected by the usual capillary theory. The same high cohesion is found between two beads in contact. A precise description of the position of the contact line accounts for the unexpectedly high resistance to erosion. Finally, we explore the dynamics of sinking of a granular raft, which happens when the vertical deflection of the interface exceeds a critical deformation. The oil thread formed during the sinking thins following an unusual path between the two classical self-similar regimes, delaying the onset of the final regime. This result emphasizes the decisive role boundary conditions can play in the transition between self-similarities
Wilkinson, Dorothy Kate. "Functional characterisation of the lipid raft protein stomatin." Thesis, University of Leeds, 2005. http://etheses.whiterose.ac.uk/448/.
Повний текст джерелаConrad, Cathrin Sonja. "Polybutadien und Butadien enthaltende Copolymere mit gezielt eingebauten vulkanisierbaren Gruppen durch RAFT-Polymerisation." Doctoral thesis, Niedersächsische Staats- und Universitätsbibliothek Göttingen, 2013. http://hdl.handle.net/11858/00-1735-0000-0022-5E9E-D.
Повний текст джерелаSeifert, Denis. "Synthese und Charakterisierung von sensitiven vernetzungsfähigen Blockcopolymeren mittels RAFT." Doctoral thesis, Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2005. http://nbn-resolving.de/urn:nbn:de:swb:14-1132231440987-09334.
Повний текст джерелаYilmaz, Beren. "An Anlaytical And Experimental Study On Piled Raft Foundations." Master's thesis, METU, 2010. http://etd.lib.metu.edu.tr/upload/12611500/index.pdf.
Повний текст джерела25 m and 30 m respectively. The numbers of piles are increased from 63 to 143. All other parameters are kept constant. The results showed that again an optimum number of piles will be sufficient to reduce the settlement to the acceptable level. The analytical methods indicate a similar behavior. The comparison and results are presented in the study.
Peng, Wentao [Verfasser]. "Binary Planet–Satellite Nanostructure Using RAFT Polymer / Wentao Peng." Göttingen : Niedersächsische Staats- und Universitätsbibliothek Göttingen, 2020. http://d-nb.info/1234846802/34.
Повний текст джерелаGiannopoulos, Konstantinos. "Numerical analysis of the reuse of piled raft foundations." Thesis, Imperial College London, 2011. http://hdl.handle.net/10044/1/9101.
Повний текст джерелаBowes, Angela. "Novel synthesis of block copolymers via the RAFT process." Thesis, Link to the online version, 2007. http://hdl.handle.net/10019/976.
Повний текст джерелаJohnson, Iain Joseph. "Synthesis and characterisation of polymeric materials via RAFT polymerisation." Thesis, Durham University, 2013. http://etheses.dur.ac.uk/8452/.
Повний текст джерелаSasso, Barbara. "Synthesis of ω-end functional polymers by raft polymerization". Thesis, University of Manchester, 2008. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.492065.
Повний текст джерелаCUNATI, DIANA. "Ruolo dei lipid raft nel metabolismo della proteina prionica." Doctoral thesis, Università degli Studi di Milano-Bicocca, 2011. http://hdl.handle.net/10281/27001.
Повний текст джерелаNguema, Edzang Ronald W. "Synthèse et caractérisation de polymères à propriétés rédox pour un contrôle des propriétés d'adhésion bactérienne." Thesis, Toulon, 2016. http://www.theses.fr/2016TOUL0006/document.
Повний текст джерелаDue to the reversible redox properties of ferrocene and its antibacterial activity, ferrocenyl-based polymers are useful for the synthesis of new anti-adhesive binders for marine antifouling coatings. This study reports the homopolymerization and copolymerization with lauryl methacrylate of ferrocenyl-based methacrylic monomers. Ferrocenylmethyl methacrylate (FMMA) as well as four novel monomers, namely 2- (ferrocenylmethoxy)ethyl methacrylate (FMOEMA), 3-(ferrocenylmethoxy)propyl methacrylate (FMOPMA),4-(ferrocenylmethoxy)butyl methacrylate (FMOBMA) and 2-(ferrocenylmethoxy)methylethyl methacrylate (FMOMEMA) were first synthesized, and subsequently polymerized by the RAFT process. The homopolymerization kinetics were investigated by in situ NMR. The radical polymerization was controlled by using 2-cyanoprop-2-yl dithiobenzoate (CPDB) as a chain transfer agent, at 70 °C in deuterated toluene. These monomers containing a ferrocenyl moiety with alcoxy linkers were found to be as reactive as FMMA in RAFT polymerization, resulting in conversions of 96% and in polymers with low dispersities (ÐM < 1.6). Monomer conversion follows a first order kinetics (up to 80%) with a linear increase in the molecular mass as a function of the monomer conversion. By using the FMMA monomer as a reference, the length of the alcoxy linker between the ferrocene unit and the backbone was increased for FMOEMA, FMOPMA, FMOMEMA and FMOBMA to improve the mobility of the side groups. This increase in macromolecular mobility led to a significant decrease of glass transition temperatures of the homopolymers. In addition, diblock copolymers exhibited two glass transition temperatures indicating that the two blocks are incompatible. The electrochemical properties of the monomers and those of the polymers were characterized using cyclic voltammetry. Finally, the anti-adhesive properties of these homopolymers and diblock copolymers toward marine bacteria were evaluated
Özyürek, Zeynep. "Thermoresponsive Glycopolymers via Controlled Radical Polymerization (RAFT) for Biomolecular Recognition." Doctoral thesis, Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2007. http://nbn-resolving.de/urn:nbn:de:swb:14-1190291104620-73670.
Повний текст джерелаFatemi-Ardakani, B. "A contribution to the analysis of pile-supported raft foundation." Thesis, University of Southampton, 1987. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.379319.
Повний текст джерелаAkrach, Majda. "Carbon black dispersion using polymeric dispersants prepared via raft polymerisation." Thesis, University of Warwick, 2012. http://wrap.warwick.ac.uk/103089/.
Повний текст джерелаEksteen, Zaskia-Hillet. "Hybrid hydrogels based on RAFT mediated poly(N-vinyl pyrrolidone)." Thesis, Stellenbosch : University of Stellenbosch, 2009. http://hdl.handle.net/10019.1/4822.
Повний текст джерелаThesis submitted in partial fulfilment for the degree of Master of Science (polymer science) at Stellenbosch University
ENGLISH ABSTRACT: The goal of this study was to synthesize hybrid hydrogels via a chemical crosslinking mechanism through use of chain end functional poly(N-vinyl pyrrolidone)(PVP) with various topologies. The crosslinking chemistries should be benign in nature i.e. at physiological pH ranges and at 37 °C. The degradation products should be biologically tolerable and renal clearance should be possible (< 30 000 g/mol PVP0. PVP of various topologies, controlled molar mass and quantitative chain end functionality was obtained via Reversible Addition Fragmentation chain Transfer (RAFT) mediated polymerization (PDI = 1.1- 1.4). The synthesized polymers were chain end functionalized to introduce thiol or aldehyde moieties. Thiol chain ends were obtained through post polymerization modification of xanthate functional PVP with either aminolysis or reduction. The aldehyde moiety was obtained by post polymerization modification of xanthate end functional PVP with sequential hydrolysis and thermolysis. Thiol functional four arm star PVP was reacted with acrylate difunctional poly(ethylene glycol) (DIAC PEG) crosslinker under standard Michael addition conditions. In order to obtain thioether crosslinked hydrogels from tetra functional star PVP molecules it was found that a minimum thiol functionalization of 30% and a molar ratio of acrylate:thiol of 1:1.1 is required. The Schiff base reaction was used to synthesize imine or secondary amine (after reduction) crosslinks with the lysine residues on either lysozyme or bovine serum albumin (BSA) or the primary amines of bis-(2-amino ethyl)amine). Hydrogels were obtained from aldehyde functionalized PVP molecules with a fraction of functional aldehyde chain ends of 0.88 for difunctional molecules and 0.50 for tetra functional star PVP molecules with lysozyme or BSA crosslinkers. The reaction rate was favoured by lowered pH (<6.0) and an optimum molar ratio of amine : aldehyde of 1:0.8. Hydrogels were analyzed by equilibrium swelling calculations to determine the molar mass between crosslinks and the estimated pore size. In both crosslinking systems the properties of the formed hydrogels were seen to be affected by molar ratio used and by the topology of the crosslinking agent. PVP BSA and PVP PEG hydrogels were tested for 24 h and 48 h cell viability by using H9C2 myoblast cells. A concentration range of 0.25 x 10(2) to 0.01 g/mL was studied. Cell mortality was tested by Trypan blue staining and results were verified with MTT assay. A very low cell death precentage (<37%)was observed. Cells even appeared to experience a stimulatory effect after 48 h of exposure at low concentrations of PVP PEG hydrogel treatments. The properties of the formed hydrogel could be tuned by the molar mass ratios of PVP and crosslinker. The functionality of the crosslinker directly affects the molar mass between crosslinks and thus indirectly the degradation profile. It was concluded that PVP molecules with various topologies, well-defined molar masses and chain end functionality could be obtained via RAFT mediated polymerization. Obtained polymers were successfully modified and crosslinked to obtain hydrogels with stoichiometrically tuneable properties i.e. initial swelling ratio, degradation time, molar mass between crosslinks. The hydrogels had very positive cell viability results that would definitely justify further research into these materials as “tissue-mimetic” materials.
AFRIKAANSE OPSOMMING: Die doel van die studie is om poli(N-viniel pirollidoon) (PVP) gebaseerde hibried hidrogelle te sintetiseer deur middel van kovalente kruisbindings met toepaslike kruisverbinder molekules. Die chemiese reaksies betrokke in die vorming van hierdie kovalente kruisbindings moet gematig van aard wees, by fisiologiese pH en by 37 °C plaasvind. Die degradasieprodukte van die hibried-hidrogel moet biologies verdraagsaam en ook uitskeibaar deur die endokrinologiese sisteem wees. PVP van verskillende topologieë, beheerde molêre massa en kwantitatiewe kettingendfunksionaliteit is berei deur ‘n omkeerbare addisie-fragmentasiekettingoordrag (OAFO)-beheerde polimerisasieproses (PDI = 1.1-1.4). Xantaat-kettingend-PVP is aangepas na thiol of aldehied kettingendfunksies. Thiolendfunksies is verkry deur middel van ‘n aminolisasie-reaksie. Xantaat kettingend-PVP is stapsgewys gemodifiseer deur hidroliese en verhittingstappe om die aldehied ketting-endfunksionaliteit te bekom. Thiol ketting-endfunksionele vier-armige ster-PVP is kovalent gebind aan difunksionele poly(etileen glikol) deur middel van die Michael-addisiereaksie. PVP PEG hidrogelle het slegs gevorm met vier-armige ster-PVP molekules wat oor ‘n minimum van 30 % thiol-funksionaliteit beskik het en ‘n optimale molêre massa verhouding van 1:1.1 vir ankrilaat to thiol. Die Schiff-basisreaksie is gebruik om hidrogel te sintetiseer wat met imiene of amiene (na redusering) kovalente bindings gekruisbind is. In hierdie sisteme het hidrogel slegs gevorm as die aldehied-PVP molekules oor ‘n fraksie funksionele kettingend-waarde van 0.88 vir dialdehied-PVP molekules en 0.5 vir vier armige ster-PVP molekules beskik het. Die reaksie snelheid van die Schiff-basis kovalente bindings is bevoordeel deur die pH te verlaag (≤ 6.0) en ‘n gunstige molêre massa verhouding van 1:0.8 vir die nukleofiel teen oor die akseptor molekule is waargeneem. Ewewigswel berekeninge is gebruik om die molêre massa tussen kruisbindings en die gemiddelde benaderde porieë binne die drie-dimensionele interne struktuur van die hydrogel te bepaal. Die seltoksisiteit van PVP-BSA en PVP-PEG hidrogelle is oor 24 h en 48 h in die teenwoordigheid van H9c2 mioblast-selle getoets. Die hydrogel behandelings is uitgevoer in ‘n konsentrasie reeks van 0.25 x 10(2) tot 0.01 g/mL. Selmortaliteit is getoets deur ‘n Trypan-blou verkleuringstudie. Hierdie resultate is ondersteun deur MTT sel-lewensvatbaarheidstoetse. ‘n Lae selmortaliteit (≤ 37 %) is waargeneem en, opspraakwekkend, het van die selle na 48 h verhoogde vitaliteit getoon in die teenwoordigheid van lae konsentrasies PVP-PEG hidrogelle. Dit is bevind dat hidrogel eienskappe deur stoichiometriese molêre massa verhoudings asook die keuse in die topologie van kruisverbinder beïnvloed word. Hierdie eienskappe het ‘n direkte effek op die degradasieprofiel van die gevormde hidrogel. Samevattend dus is PVP molekules met ‘n variasie van topologieë, spesifieke molêre massas en kettingfunksionalitete deur middel van OAFO-gemedieerde polimerisasies gesintetiseer. Xantaatkettingendfunksionele PVP-molekules kon suksesvol omgeskakel word na die kettingendfunksionaliteit van ons keuse om ‘n hibriedhidrogel met stoichiometries-manupileerbare eienskappe te sintetiseer. Die positiewe sel-lewensvatbaarbheidstudie resultate staaf verdere ondersoeke in hierdie PVPgebaseerde hibried hidrogelmateriaal as ‘n weefsel nabootsingsmateriaal.
Möhrke, Julia. "Kinetik der konventionellen radikalischen und der RAFT-Polymerisation an Nanopartikeloberflächen." Doctoral thesis, Niedersächsische Staats- und Universitätsbibliothek Göttingen, 2016. http://hdl.handle.net/11858/00-1735-0000-0028-87D3-9.
Повний текст джерелаSmith, Steven Oliver. "Raft : automated techniques for diagnosing, reproducing, and fixing concurrency bugs." Thesis, University of Cambridge, 2014. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.648869.
Повний текст джерелаZargar, Amin. "Sequence modeling of raft polymerizations with the method of moments." College Park, Md.: University of Maryland, 2008. http://hdl.handle.net/1903/8782.
Повний текст джерелаThesis research directed by: Dept. of Chemical and Biomolecular Engineering. Title from t.p. of PDF. Includes bibliographical references. Published by UMI Dissertation Services, Ann Arbor, Mich. Also available in paper.
Garcia, Oscar. "Rafue Ite! Ethnographie d’un bal rituel amazonien (Murui-Muina-Uitoto, Amazonie colombienne)." Thesis, Paris Sciences et Lettres (ComUE), 2018. http://www.theses.fr/2018PSLEH178.
Повний текст джерелаThis thesis is dedicated to the ritual balls (ritual dances) of the Murui-Muina (also called Uitoto), a people from the North-West area of the Amazon forest (from the region of the Medio-Caquetá). It is an analysis of the different rites that make up the dances and the shamanism of the Murui-Muina, based on an ethnographic study e of the "Yuakɨ Ball" (or "Ball of the Fruits").This research shows that the Yuakɨ Ball is an event that brings together different patrilineage groups and aims at managing the environment surrounding the society and healing from epidemics. The thesis is composed of four parts, divided into two volumes. The first volume is dedicated to murui-muina shamanism and the second to Yuakɨ's ball. In the two volumes, cosmology, ritual procedures and the relationships between those participating in the dances are studied. This analysis is based on an ethnographic study but also on ancient oral traditions, transmitted from one historical period to the next one and told during mythical ceremonies and narrations, such as the bakakɨ and the zomarafue. The existing ethnography on the Murui-Muina will thus be reunited, reinterpreted and compared to the new data collected.In the ecological model of this people, which emerges from this thesis, life is conceived as an incessant struggle between human and non-human groups, regulated by norms such as the prohibition of endo-cannibalism or the revenge (the only legitimate violence). Human and non-human groups are placed under the authority of "Master" spirits and human beings must negotiate their lives with other beings who inhabit their environment (animals, plants, minerals, etc.). This research also shows the mnemonic strategy used by Murui-Muina during the rites studied and wants to be one of the rare contributions to the study of ritual dance in the Amazon area. It is therefore a study that combines anthropology of nature, anthropology of memory and anthropology of dance
Noble, Gavin Thomas. "Modelling glycocluster effects using artificial lipid rafts." Thesis, University of Manchester, 2012. https://www.research.manchester.ac.uk/portal/en/theses/modelling-glycocluster-effects-using-artificial-lipid-rafts(10686397-b8ea-473d-ab27-8fc79b4c424b).html.
Повний текст джерелаRussum, James. "Controlled Radical Polymerizations in Miniemulsions: Advances in the Use of RAFT." Diss., Available online, Georgia Institute of Technology, 2005, 2005. http://etd.gatech.edu/theses/available/etd-10112005-105314/.
Повний текст джерелаJones, Christopher, Committee Chair ; Schork, F. Joseph, Committee Co-Chair ; Weck, Marcus, Committee Member ; Meredith, Carson, Committee Member ; Agrawal, Pradeep, Committee Member.