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台灣與印尼雙邊跨境移工政策:以在台逃逸印尼勞工為例 / Coordinating Migrant Labor Policy between Taipei and Jakarta: The Case of Runaway Indonesian Workers范安曼, Faustina, Anselma Unknown Date (has links)
由於印尼為世界上人口最多的國家之一,因此憑藉著此一優勢印尼成為了勞工輸出大國,但是非常多的印尼勞工在外國工作時面臨虐待,因而產生了不少問題,另一方面,台灣是印尼勞工們選擇工作的優先地,主要原因有三個,第一為較高的薪水,第二為較好的生活品質及良好的工作環境,第三不公平對待相較於他國較少發生,儘管如此台灣政府仍面臨著管理外籍勞工的問題,特別是逃逸的外籍勞工的問題,而在台灣的逃逸外勞比例中,印尼勞工占了最高比例。
先前的研究主要在於分析台灣的逃逸外勞現象,並且把此一現象歸因於台灣的移工政策所造成,但是現有的研究主要是針對菲律賓的勞工而不是印尼勞工,因此對於印尼逃逸勞工現象研究則相較較少。
考慮到外籍勞工議題涵蓋的層面多元,如多方的參與者,因此本篇論文將專注於闡述與探討負責輸出勞工及輸入勞工國家的角色及政策。本篇論文主要分為兩部份,第一部分,由於台灣的移工政策對於外國勞工非常嚴格,因此台灣的移工政策造成了印尼勞工過多的負擔,第二台灣和印尼政府無效率的配合,兩國政府只專注於表面並無徹底了解並從其根本解決勞工問題,這兩項因素造成了高比率的逃逸印尼勞工問題,除此之外,本篇論文亦將包含清楚的台灣政府和印尼政府的勞工政策發展,為了更清楚了解此一議題,本篇論文也向移民署收容所作問卷調查,訪問避難所的逃逸勞工,和研究台印勞工現象的專家學者們進行團體討論,本篇分析結果來自問卷調查及訪問,並將此一結果與現有的印尼及台灣政府的政策與合作進行分析。 / As one of the most populous country in the world, Indonesia’s predominance is sending its human resources to work abroad. However, many Indonesian overseas workers encounter mistreatment during their work time which leads to several arising problems. On the other hand, Taiwan has become one of the preferred destination countries due to three reasons; higher salary, better living and working conditions, and low mistreatment cases compare to other destination countries. Despite that, Taiwan government still encounters issues in managing foreign workers. Runaway foreign worker is a major issue in Taiwan’s labor market and Indonesian workers are accounted as the highest runaway foreign workers in Taiwan.
Previous researches have been conducted to analyze the phenomenon of runaway foreign workers in Taiwan and most of them addressed Taiwanese guest worker policy as the major reason. Research on runaway Indonesian workers in particular is very limited as most of the existing researches focused on Filipinas workers.
Taking into account that foreign workers issue is a multi-faceted phenomenon which involves various actors, this thesis acknowledges the roles and policies from both sending and host states. Therefore this thesis delivers two arguments. First, Taiwan’s guest worker policy has put excessive burden on Indonesian workers as Taiwan employs highly restrictive policy towards foreign workers. Second, Indonesia and Taiwan’s ineffective cooperation is unable to address the existing runaway Indonesian workers issue as it emphasizes more on scratching the surface than dealing with the root causes. These two variables have inadvertently contributed to the high number of runaway Indonesian workers. In addition, this thesis also delivers a clear labor policy development in Indonesian and Taiwan government to understand each institution’s in-take related to labor issues. In order to provide comprehensive findings, this thesis conducts survey with the Indonesian runaway workers in Detention Center, interview with the runaway Indonesian workers in shelters, and focus group studies with Indonesian and Taiwanese experts who are dealing with such phenomenon. The analysis is drawn from the results of survey and interview, and then is connected to the current Indonesian and Taiwanese policies and cooperation in addressing particular issue.
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Porphyrin-based [3]- and [4]rotaxanes : towards an adaptable molecular receptorRoche, Cécile 20 April 2012 (has links) (PDF)
Rotaxanes and porphyrins are two particularly active fields of research in chemistry. However,molecules that combine the interesting properties of these types of structures are not so common. In this thesis we describe new porphyrin-based multi-rotaxanes, whose syntheses constitute interesting challenges.Porphyrins linked to two or four coordinating macrocycles were synthesised. The "gathering-andthreading" effect of copper(I) was used to thread molecular rods through the rings; the subsequent introduction of stoppers led to the formation of rotaxanes. In the case of the porphyrinic bis-macrocycle a [4]rotaxane was obtained. Host/guest complexation studies with rigid nitrogen ligands showed that the rotaxane behaves as a distensible molecular receptor that can adopt an "inflated" or "deflated" conformation and adjust its shape to the size of the guest. In the case of the porphyrinic tetra-macrocycle the formation of a [3]rotaxane of novel architecture was observed.The synthesis of a new, more rigid bis-macrocycle is in progress. This compound will be used for the construction of a [4]rotaxane that could act as a molecular press able to change the conformation of a guest substrate by compression.
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Investigation of the diffusion mechanisms of several hydrocarbons in the Metal-Organic-Framework Zn(tbip)Seehamart, Kompichit 09 May 2011 (has links) (PDF)
Most of the computer simulations of molecules in Metal-Organic Frameworks (MOFs) to be found in the literature are done with rigid framework. But, Molecular Dynamics (MD) simulations of the self-diffusivity, Ds, of ethane within the one-dimensional 4.5 Å channels of the MOF type Zn(tbip)(H2 tbip = 5-tert-butyl isophthalic acid) presented in this work have shown not only quantitative, but also qualitative, differences in the Ds values for fixed and flexible lattices. Particularly, the dependence of Ds upon the concentration of molecules, c, is strongly influenced by the lattice flexibility. The reasons for this influence are investigated with the aid of probability density plots, free energy landscapes and barriers, along with a determination of the structural changes accompanying increasing c. It is found that for flexible lattices, the tighter, more constrained parts of the channels become wider at higher c; this allows more molecules to diffuse in the central region of the channels.
The investigations for Zn(tbip) have been extended to three equimolar mixtures of ethane/ethane, CO2/ethane and CO2/methanol. The simulations take into account the lattice flexibility. The diffusional characteristics are discussed in relation to molecule properties and lattice geometry. The results show that Zn(tbip) may be a useful material for separating methane/ethane and CO2/ethane mixtures at low concentrations, and CO2/methanol mixtures at high concentrations.
The temperature and concentration dependence of the self-diffusivity of propane diffusion in Zn(tbip) have been investigated as well by performing normal MD and hyper-MD with bias potential simulations. The obtained temperature dependence of the self-diffusivities is analyzed using an Arrhenius relationship, yielding the activation energy to be 9.53 kJ/mol and the pre-exponential factor to be 4.48×10-9 m2s-1. Using this hyper-MD method, interesting mechanisms of the propane molecules able to pass each other and exchange their sites in the channels can be observed. Because of mutual hindrance of propane molecules, the propane self-diffusivities decrease with increasing concentration.
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An?lise da rela??o entre apego ao lugar, satisfa??o e fidelidade dos visitantes em destinos tur?sticos ambientais: um estudo em Fernando de Noronha/PESantoro, Monica Almeida Gavilan 10 March 2014 (has links)
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Previous issue date: 2014-03-10 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / The competition among tourist destinations environmental generates the emergent need to find different strategies to close down if the purpose of delight and retain their visitants. A customer satisfaction, loyalty and the development of attachment to place form a solid compound in search of promotion a tourist destination. This study presents the general objective analysis of the relationship between attachment to place, satisfaction and loyalty of visitors, in the archipelago of Fernando de Noronha / PE. Therefore, a model will be used as reference, where they will be analyzed various constructs related to attachment to place, satisfaction and loyalty, as well as the relations between them. The methodology used in the study consists of an exploratory, descriptive, where the sample is random and consists of individuals who visited Fernando de Noronha on a pre-defined period of ten days. Based on a sample table, we defined a quantitative equivalent of 246 questionnaires, which will be applied when the visitor leaves the destination, the departure lounge of airport. A proposal focuses on the possibility to get results able to understand the subjective and intriguing relationship that involves the triad attachment to place, satisfaction and loyalty, trying to thus provide subsidies for optimizing environmental tourist destination / A competitividade entre os destinos tur?sticos ambientais gera a emergente necessidade de encontrar estrat?gias diferenciadas que tenham o prop?sito de encantar e reter seus visitantes. A satisfa??o do cliente, sua fideliza??o e o desenvolvimento de apego ao lugar formam um composto s?lido na busca da promo??o de um destino tur?stico. O estudo em quest?o, apresentou como objetivo geral uma an?lise, da rela??o entre apego ao lugar, satisfa??o e fidelidade dos visitantes, no Arquip?lago de Fernando de Noronha/PE. Para tanto, foi utilizado um modelo como refer?ncia, onde foram analisados v?rios construtos ligados ao apego ao lugar, satisfa??o e fidelidade, assim como suas rela??es entre si. A metodologia utilizada na realiza??o do estudo consiste em uma pesquisa explorat?ria, descritiva, sendo a amostra aleat?ria e composta por indiv?duos que visitaram Fernando de Noronha no per?odo de 30 de abril de 2013 a 03 de maio de 2013. Baseando-se em uma tabela amostral, definiu-se um quantitativo equivalente a 246 question?rios, que foram aplicados no momento que o visitante abandonou o destino, no sal?o de embarque do aeroporto. Os resultados demostram que os visitantes de Fernando de Noronha neste per?odo apresentaram-se satisfeitos com o destino. A sua grande maioria, 90,5% est? visitando o Arquip?lago pela primeira vez e demonstrou pretens?o de retorno e de indica??o, o que nos remete a uma poss?vel fideliza??o do destino
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Efeitos de confinamento em líquidos iônicos hidratadosZanatta, Marciléia January 2017 (has links)
Líquidos iônicos imidazólios (LIIs) associados a ânions com caráter básico foram sintetizados, caracterizados e seu comportamento estudado em solução. Inicialmente a troca isotópica H/D preferencial no grupo C2-CH3 de sais de 1-nbutil-2,3-dimetilimidazólio (BMMI) foi avaliada. Ficou evidente que o contato entre os pares de íons e a atuação do ânion como uma base neutra influenciaram fortemente a deuteração. Após a análise dos resultados de RMN, cálculos de DFT (Teoria do Funcional de Densidade) e Difração de Raios X, um complexo entre uma molécula de água e alguns LI foi sugerido, modificando fortemente a estrutura organizacional e afetando também a troca isotópica nestes sais. Através do mecanismo reacional proposto, surgiu a possibilidade de deuteração de novos substratos contendo H ácidos, usando os LIIs como catalisadores. A reação de troca isotópica em alcinos e cetonas foi estudada e bons resultados foram obtidos. O efeito da variação de cátions e ânions na atividade catalítica foi analisado, assim como a variação dos substituintes dos substratos. Além disso, um estudo cinético foi realizado através de análises de RMN de 1H e o mecanismo reacional foi proposto. Por fim, a capacidade de formação de pares iônicos em soluções aquosas de LIIs foi avaliada na captura de CO2. Ótimos resultados foram obtidos e atribuídos à ocorrência de sorção física e química devido à ativação da água pelo LII. / Imidazolium based ionic liquids (ImIL) associated with basic anions were synthesized, characterized and studied. Initially the preferred H/D isotopic exchange to C2-CH3 group of 1-nbutyl-2,3-dimethylimidazolium salts (BMMI) was studied. In this context, it became evident that the ion-pairing formation and the anion action as a neutral base strongly influence the deuteration reaction. NMR analysis, theoretical calculation (Density Functional Theory) and X-ray Diffraction have been performed and a complex between a water molecule and the IL have been suggested, strongly modifying the IL structure and characteristics. The isotope exchange reaction in alkynes and ketones was studied using imidazolium based ionic liquids as catalysts and good results obtained. The effect of cation and anion variation on the catalyst activity were analyzed, also a variation of the substrate substituent’s. Also, a kinetic study was performed by 1H NMR analyzes and the reaction mechanism were proposed. Finally, the ability to form ion pair contact of ILs in aqueous solutions was evaluated for CO2 capture. Great results were obtained and this success can be attributed to the occurrence of physical and chemical sorption due to water activation by the IL.
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Cellulose nanocrystals : surface modification and advanced materials / Nanocristaux de cellulose : modification de surface et matériaux avancésLin, Ning 24 June 2014 (has links)
Ce travail porte sur les propriétés des nanocristaux de cellulose, leur modification de surface et le développement de matériaux avancés. Diverses approches sont utilisées sur ces substrats nanométriques visant à modifier leurs propriétés de surface et étendre leur utilisation dans des applications très sophistiquées, telles que la postsulfation et la désulfatation, le greffage et l'adsorption de polymères, l’oxydation sélective, le greffage moléculaire et l'inclusion "hôte-invité". Sur la base de modifications de surface, l'analyse des propriétés (pour différents taux de groupements sulfates) et divers nanomatériaux dérivés des nanocristaux de cellulose sont étudiés et préparés, notamment des nanocristaux sulfatés à différents taux, des nanocomposites extrudés, des éponges biocomposites et des hydrogels supramoléculaires. L'effet d’un gradient de groupements sulfates sur la chimie de surface, la morphologie et les propriétés physiques des nanocristaux de cellulose est discuté et notamment quatre modèles de section transversale sont comparés pour la détermination de la mesure du degré de substitution surfacique des nanocristaux de cellulose. Une stratégie nouvelle de protection impliquant une double couche polymère et la compatibilisation physique et/ou chimique des nanocristaux de cellulose est proposée afin de promouvoir à la fois la stabilité thermique des nanoparticules et la compatibilité des nanocristaux avec des matrices polymères non polaires au cours de la mise en forme par extrusion. En participant àla réticulation pour la construction de matériaux avancés, des nanocristaux de cellulose sélectivement oxydés (et de la cellulose microfibrillée oxydée pour comparaison) sont introduits dans de l'alginate pour développer des éponges biocomposites présentant une meilleure stabilité mécanique et une meilleure stabilité structurelle. Grâce à la conception intelligente par inclusion 'hôte-invité' in situ entre des nanocristaux de cellulose chimiquement modifiés et la cyclodextrine,deux polysaccharides hydrophiles sont combinés dans des hydrogels supramoléculaires pour l'administration de médicaments. En un mot, cette thèse contribue à l’avancée des nanocristaux de cellulose dans les domaines de l'analyse des propriétés et le développement des applications. / The present work focuses on the properties of cellulose nanocrystals, their surface modification and development of advanced materials. Diverse approaches are employed on these nanoscaled substrates aiming to modify their surface properties and extend their use in highly sophisticated applications, such as postsulfation and desulfation, polymer grafting and adsorption, selective oxidation, molecular grafting, and ‘host-guest' inclusion. On the basis of surface modifications, properties analysis (for different sulfate group contents) and various nanomaterials derived from cellulose nanocrystals are investigated and prepared, including gradient sulfated nanocrystals, extruded nanocomposites, biocomposite sponges, and supramolecular hydrogels. The effect of gradient degrees of sulfate groups on cellulose nanocrystals to surface chemistry, morphology and physical properties are discussed, particularly four cross-section models are compared for the determination of the surface degree of substitution on cellulose nanocrystals. A novel strategy involving a double-polymer-layer shield and physical and/or chemical compatibilization of cellulose nanocrystals is proposed, in order to realize both improvement of thermal stability and promotion of compatibility for nanocrystals with non-polar polymeric matrices during processing by melt-extrusion. With the idea of participating as crosslinking aid for the construction of advanced materials, selectively oxidized cellulose nanocrystals (with oxidized microfibrillated cellulose as comparison) are introduced in alginate for the development of biocomposite sponges with improved mechanical stability or structural stability. Through the smart design of in situ ‘host−guest' inclusion between chemically modified cellulose nanocrystals and cyclodextrin, two hydrophilic polysaccharides are combined in supramolecular hydrogels for use as drug delivery. In a word, this dissertation contributes to the advances of cellulose nanocrystals in the topics of property analysis and application development.
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Efeitos de confinamento em líquidos iônicos hidratadosZanatta, Marciléia January 2017 (has links)
Líquidos iônicos imidazólios (LIIs) associados a ânions com caráter básico foram sintetizados, caracterizados e seu comportamento estudado em solução. Inicialmente a troca isotópica H/D preferencial no grupo C2-CH3 de sais de 1-nbutil-2,3-dimetilimidazólio (BMMI) foi avaliada. Ficou evidente que o contato entre os pares de íons e a atuação do ânion como uma base neutra influenciaram fortemente a deuteração. Após a análise dos resultados de RMN, cálculos de DFT (Teoria do Funcional de Densidade) e Difração de Raios X, um complexo entre uma molécula de água e alguns LI foi sugerido, modificando fortemente a estrutura organizacional e afetando também a troca isotópica nestes sais. Através do mecanismo reacional proposto, surgiu a possibilidade de deuteração de novos substratos contendo H ácidos, usando os LIIs como catalisadores. A reação de troca isotópica em alcinos e cetonas foi estudada e bons resultados foram obtidos. O efeito da variação de cátions e ânions na atividade catalítica foi analisado, assim como a variação dos substituintes dos substratos. Além disso, um estudo cinético foi realizado através de análises de RMN de 1H e o mecanismo reacional foi proposto. Por fim, a capacidade de formação de pares iônicos em soluções aquosas de LIIs foi avaliada na captura de CO2. Ótimos resultados foram obtidos e atribuídos à ocorrência de sorção física e química devido à ativação da água pelo LII. / Imidazolium based ionic liquids (ImIL) associated with basic anions were synthesized, characterized and studied. Initially the preferred H/D isotopic exchange to C2-CH3 group of 1-nbutyl-2,3-dimethylimidazolium salts (BMMI) was studied. In this context, it became evident that the ion-pairing formation and the anion action as a neutral base strongly influence the deuteration reaction. NMR analysis, theoretical calculation (Density Functional Theory) and X-ray Diffraction have been performed and a complex between a water molecule and the IL have been suggested, strongly modifying the IL structure and characteristics. The isotope exchange reaction in alkynes and ketones was studied using imidazolium based ionic liquids as catalysts and good results obtained. The effect of cation and anion variation on the catalyst activity were analyzed, also a variation of the substrate substituent’s. Also, a kinetic study was performed by 1H NMR analyzes and the reaction mechanism were proposed. Finally, the ability to form ion pair contact of ILs in aqueous solutions was evaluated for CO2 capture. Great results were obtained and this success can be attributed to the occurrence of physical and chemical sorption due to water activation by the IL.
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Have Fun While Waiting : A study about the integration of interactive digital technology in amusement parks / Ha roligt medan du väntar : En studie om integreringen av interaktiva digitala tekniker inom nöjesfältKrauser, Erika January 2015 (has links)
Consumers in the UK are spending about three days of waiting in queues every year. The majority of the French consumers would choose another business if it offered faster service. Research on current waiting times are therefore focusing on finding solutions to reduce consumers wait by reducing perceived waiting time and the dissatisfaction that arises with queues. The purpose of this study is to find out how to make the queues at the theme parks more fun with interactive digital technologies and the impact these have on the guest experience. A survey is carried out to find out how mobile usage looks at amusement parks today and how the respondents place themselves against the integration of interactive digital technologies in amusement parks. Even an interview, with the leader of the world's first synchronized queue entertainment the Helix game, is implemented. Theories show that one can reduce the perceived waiting time by introducing new environmental stimuli and fill the time with various activities that visitors can be consumed by. Thus increases the guest experience and the queues are less boring and time-consuming. One way of doing this is to incorporate mobile digital interactive techniques, which respondents would like to see more of. / Konsumenter i Storbritannien spenderar ungefär tre dagar på att vänta i köer per år. Majoriteten av de franska konsumenterna skulle välja en annan affär om den erbjöd en snabbare service. Forskning gällande väntetider fokuserar därför på att hitta lösningar för att minska konsumenternas väntan genom att reducera uppfattad väntetid och på så sätt minska missnöjet som uppstår med köer. Studiens syfte är att ta reda på hur man kan göra köerna på nöjesfält roligare med hjälp av interaktiva digitala tekniker och vilka effekter dessa har på gästupplevelsen. En enkät har genomförts för att ta reda på hur mobilanvändandet ser ut på nöjesfält idag samt hur respondenter ställer sig mot integreringen av interaktiva digitala tekniker på nöjesfält. Även en intervju med projektledaren för världens första synkroniserade kö-underhållning, Helix-spelet, genomförs. Teorier visar på att man kan minska de uppfattade väntetiderna genom att introducera nya miljöstimulanser samt fylla tiden med olika aktiviteter som besökarna kan uppslukas av. Då ökar man gästupplevelsen samt gör köerna roligare. Ett sätt att göra detta på är att integrera mobila digitala interaktiva tekniker vilket respondenterna vill se mer av.
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Polymer multilayers : fundamental aspects and application for biomaterials / Multicouches de polymères : aspects fondamentaux et application dans le domaine des biomatériauxSéon, Lydie 30 September 2014 (has links)
La surface d'un matériau est le lieu privilégié des interactions entre le matériau et son environnement. La technique couche-par-couche, qui consiste en un dépôt alterné de polyanions et de polycations, ouvre de nouvelles perspectives dans le domaine des biomatériaux pour le contrôle de ces interactions. La cohésion des films multicouches de polyélectrolytes est principalement assurée par des interactions électrostatiques mais a été étendue à d'autres forces motrices telles que les interactions hôte-invité. Nos travaux s’articulent autour de deux axes principaux. D’une part, nous nous sommes intéressés aux films multicouches de polymères neutres basés sur des interactions hôte-invité et en particulier à l'influence de la force du complexe d’inclusion b-cyclodextrine/ferrocène sur la topographie de ces films. La force de l’interaction hôte-invité a d’abord été modulée en associant différents invités (l’adamantane, le ferrocène et le pyrène) avec la β-cyclodextrine. La force du complexe b-cyclodextrine/ferrocène a été ensuite modulée par la présence de différents sels de sodium à différentes forces ioniques au cours de la construction du film. Une force d'interaction intermédiaire du complexe semble être nécessaire pour former des films continus, tandis que, si elle est trop faible, la force d'interaction limite la construction du film.D’autre part, motivé par le fait que la prévention des infections microbiennes des dispositifs médicaux implantables constitue un problème médical et financier majeur, nous avons développé de nouveaux revêtements antimicrobiens grâce à la technique couche-par-couche. Des films multicouches à base de polysaccharides contenant la cateslytine, un peptide antimicrobien, permettent l’inhibition en 24h du développement de Candida albicans et Staphylococcus aureus, qui sont des agents pathogènes communs et virulents rencontrés dans les maladies nosocomiales. La libération des peptides antimicrobiens est déclenchée par la dégradation enzymatique du film en présence des agents pathogènes. Le revêtement est ainsi qualifié d’auto-défensif. La non-cytotoxicité du film vis-à-vis des cellules humaines permet une application cliniquement pertinente pour prévenir les infections sur les cathéters. Des dimères à base de cateslytine de différentes longueurs et un dendrimère ont été synthétisés afin d'améliorer l'activité biologique du peptide d'origine, i.e. ses propriétés antimicrobiennes et antiinflammatoires. Afin d’élaborer des films antimicrobiens mécaniquement robustes, le polyuréthane (polymère entrant dans la composition des cathéters) a été fonctionnalisé par une couche de polydopamine qui peut ensuite réagir avec des groupements thiol ou amine, permettant la fixation covalente des films de polysaccharides antimicrobiens réticulés étape par étape. / The surface of a material is the privileged location, where the interactions between the material and its environment take place. In the field of biomaterials, the challenge is to control these interactions. A very versatile coating technique is the layer-by-layer deposition, which consists in the alternated deposition of polyanions and polycations. The cohesion of polyelectrolyte multilayer films is primarily ensured by electrostatic interactions but was extended to other driving forces such as host-guest interactions. Our work was constituted of two main parts.In the first part, the buildup of neutral polymer multilayer films based on host-guest interactions was studied and in particular the influence of β-cyclodextrin/ferrocene interaction strength on the topography of these films. The host-guest interaction strength was first modulated by involving different guests (adamantane, ferrocene and pyrene) in the buildup. Then, β -cyclodextrin/ferrocene interaction strength was tuned by the presence of different types and concentrations of salts during the multilayer buildup. Intermediate interaction strength seems to be required to form continuous films, whereas, if too low, the interaction strength limits the film buildup.In the second part, motivated by the fact that the prevention of pathogen colonization of implantable medical devices constitutes a major medical and financial issue, polyelectrolyte multilayers were used as tools to develop new antimicrobial coatings. Polysaccharide multilayer films containing cateslytin, an antimicrobial peptide, fully inhibited in 24h the development of Candida albicans and Staphylococcus aureus, which are common and virulent pathogens agents encountered in care-associated diseases. The release of the antimicrobial peptides was triggered by the enzymatic degradation of the film due to the pathogens themselves introducing the concept of self-defensive coating. The non-cytotoxicity of the film, towards human cells, highlights a medically relevant application to prevent infections on catheters. Different cateslytin based dimers with various lengths and one dendrimer were synthesized in order to improve the bioactivity of the original peptide, i.e. antimicrobial and anti-inflammatory properties. In order to obtain mechanically robust antimicrobial films, polyurethane (polymer that composes catheters) was functionalized with a polydopamine layer that can further react with thiol or amine groups, allowing the covalent attachment of step-by-step cross-linked antimicrobial polysaccharide films.
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On the synthesis, measurement and applications of octanuclear heterometallic ringsFaust, Thomas Benjamin January 2012 (has links)
Inorganic macrocycles have stimulated interest in recent years for their magnetic properties, their associated host-guest chemistry and their aesthetically appealing structures. These characteristics have led to suggestions that they could be exploited for the purposes of ion recognition, catalysis, as single molecule magnets, MRI agents, antibacterial agents and as part of larger architectures in a molecular machine. This thesis explores the properties of a group of chromium(III) macrocycles, with functionality tailored towards different pursuits. Firstly the magnetic properties of a newly synthesised family of ring dimers are investigated. The nature of magnetic exchange within each ring leads to a net electronic spin which, it has been proposed, could represent a quantum binary digit within a quantum information processing system. By linking together pairs of rings, the degree of inter ring communication can be determined. Such interactions are important for the correlation of spin as initiation of quantum entanglement, a pre-requisite for quantum computing. The rings can also act as fluoro-metallocrowns, hosting the molecule which templated their formation. A range of rings with different guests are synthesised and their solid and solution state structures are explored. On templating about bulky dialkyl amines hybrid organic-inorganic rotaxanes are formed where the guest is fixed. In contrast when using small amines and alkali metals, exchange of guests is possible. The dynamics of all of these systems are investigated with proton NMR, quite remarkable for such highly paramagnetic complexes.
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