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Made available in DSpace on 2014-06-12T15:52:54Z (GMT). No. of bitstreams: 2 arquivo566_1.pdf: 3129219 bytes, checksum: e74de6e8cf1387acd5da4d5cda0116f1 (MD5) license.txt: 1748 bytes, checksum: 8a4605be74aa9ea9d79846c1fba20a33 (MD5) Previous issue date: 2010 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / O presente estudo tem como objetivo discutir Modelos de Desenvolvimento à luz de conceitos de cluster, capital social e inovação. Procuramos, através de uma metodologia descritiva, apresentar as principais características dos modelos discutidos, a saber, a experiência italiana, na figura da Terceira Itália; e a experiência do Porto Digital, no Estado de Pernambuco. Antes, num primeiro momento, discutimos teoricamente os conceitos elencados acima, inserindo menções, em especial, ao caso italiano, por este ter despertado o desenvolvimento de boa parte do referencial teórico, passando pela discussão teórica acerca das redes sociais. Após isso, discutimos o modelo italiano estabelecendo um denso corte histórico descrevendo os caminhos de seu sistema de C&T (Ciência e Tecnologia), suas contradições inerentes devido à existência de patologias institucionais como a máfia e o clientelismo. Observa-se que a tradição e elementos de ordem cultural e instituições nãoformais importam bastante. Neste ponto, ainda, refletimos sobre a estranheza do fato deste modelo ter galgado sucesso de modo a contrapor-se aos modelos fordista e toyotista, ao ponto de despertar desejos de emulação. Em seguida, apontamos a experiência do Porto Digital, localizado na cidade de Recife, Pernambuco, inserida numa lógica de APL (arranjos produtivos locais) - consistindo-se em um cluster de TIC (tecnologia da informação e comunicação) o qual gera benefícios para as empresas que compõem a rede -, descrevendo algumas instituições presentes no sistema de C&T brasileiro e sua contribuição para as PMEs no país. Ainda, neste caso, tratamos dos aspectos legislativos (leis) concernentes ao processo de clustering e do caso da indústria de games. No estudo, aponta-se que tais modelos guardam aspectos similares entre si, dentre os quais se destaca a relação frutífera entre atores como Empresas (Setor Privado), Estado (Governos/Esfera Pública), Academia (Universidades) e Instituições de Apoio (Fomentos Diversos), na consubstanciação de programas de inovação e de aglomeração empresarial estabelecendo uma sinergia através de governanças locais. Em ambos os casos tratados, aos quais somamos pontuações concernentes às experiências finlandesa, britânica, japonesa, francesa e americana, há a discussão sobre as PME (Pequenas e Médias Empresas) como unidades de negócio que apresentam grande potencial de inovação quando inserida em redes, compondo tais modelos de desenvolvimento fundados em laços cooperativos. Ainda, notamos que o Estado consiste-se como ator muito importante na constituição de benefícios que priorizem as empresas lotadas em territórios (aglomerações de empresas), o fazendo através de aportes diretos ou por meio de políticas públicas específicas. Sendo assim, pretende-se apresentar como, nos casos tratados, se dá tal relação, como fora construída historicamente e de que modo os conceitos principais listados acima se referem aos mesmos

Made available in DSpace on 2014-06-12T17:21:05Z (GMT). No. of bitstreams: 2 arquivo5970_1.pdf: 926209 bytes, checksum: 8caf323cbf6ce9b156e9f8fb929cd781 (MD5) license.txt: 1748 bytes, checksum: 8a4605be74aa9ea9d79846c1fba20a33 (MD5) Previous issue date: 2005 / Este trabalho teve por objetivo analisar o pólo moveleiro de João Alfredo, Pernambuco à luz do modelo de clusters. Os resultados de pesquisas realizadas a cerca do setor de móveis são apresentados na primeira parte deste trabalho. Estas pesquisas tiveram o objetivo de caracterizar a indústria de móveis em Pernambuco, no Brasil e no mundo. Na segunda parte do trabalho, são apresentados os resultados de uma revisão bibliográfica a respeito do modelo de clusters. A partir dos conceitos apresentados sobre o modelo de clusters são propostas ações estratégicas que visam o desenvolvimento do setor moveleiro, especificamente o pólo de João Alfredo

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / An increase in the research interest related to nanomaterials, with gold-based ones being among the most studied, have been noticed. These materials are higlighted mainly due to their particular features acquired when sizes are reduced to nanometric scale. Metallic nanosystems have interesting physical properties such as photon emission and absorption, quantum confinement, among other optical phenomena. Many research works foccus on the synthesis, controlling sizes of these metallic systems. Gold clusters have been employed for diverse functions such as molecular dyagnosis,, detection of chemical/biological agents, bioengineering, ion sensing, catalysis of chemical reactions, to name a few uses. Thus, this work is foccused on the synthesis and characterization of Au15 clusters using glutathione as stabilizer, coupling the clusters to the cavities of a cyclodextrins-derived polymer. The objectives are to increase the yield on gold clusters and to avoid their formation outside the cavities of the cyclodextrin-derived polymer, to study the catalytic effect of the gold clusters in the reduction of 4-nitrophenol (PNP) by NaBH4 to 4-aminophenol (PAP). Optical UV/visible absorption, photoluminescence (PL), fourier-transform infrared spectroscopy and transmission electron microscopy (MET) were used to characterize the samples. It was observed that the polymer matrix used allowed the synthesis of Au15 clusters with characteristic absorption at 405 nm, indicative of clusters with number of atoms near 15, as well as a strong emission both in solid state and in solution. The catalytic activity of the clusters obtained in the PNP reduction to PAP was demonstrated. / Percebe-se um aumento do interesse em pesquisas relacionadas a nanomateriais, sendo o ouro um dos materiais mais estudados. Este material destaca-se principalmente pelas características particulares adquiridas quando reduzido a escala nanometrica. Nanosistemas de metais pode possuir interessantes propriedades físicas, tais como emissão, absorção de fótons, confinamento quântico. Muitas pesquisas concentraram-se na síntese, controlando o tamanho desses Sistemas de metais. Clusters de ouro têm sido empregados para diversas finalidades tais como no diagnóstico molecular, detecção de agentes químicos/biológicos, bioengenharia, sensoriamento de íons, catalise de reações químicas, dentre outras. Assim, a presente pesquisa terá como foco sintetizar e caracterizar Clusters de Au15, usando como estabilizante a glutationa, acoplada em cavidades do polímero derivado de ciclodextrinas. Os objetivos são aumentar o rendimento dos Clusters de Au e evitar que sejam formados Clusters fora das cavidades do polímero derivado das ciclodextrinas, estudar o efeito catalítico dos Clusters de Au na redução do 4-nitrofenol (PNF) a 4-aminofenol (PAF) por NaBH4. Para a caracterização foram utilizados Absorção Óptica UV-Vis e fotoluminescência (PL), espectroscopia infravermelho por transformada de Fourier (FTIR- ATR), Microscopia Eletrônica de Transmissão (MET). Pode-se perceber que a matriz polimérica utilizada possibilitou a síntese dos Clusters de Au15, com absorção característica em 405 nm, esta que é característica do Au15, bem como uma forte emissão, tanto no estado solido, quanto em solução. Foi comprovado a atividade catalítica de tais Clusters na reação de redução do 4-nitrofenol a 4-aminofenol.

Made available in DSpace on 2014-10-09T12:36:56Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T13:56:11Z (GMT). No. of bitstreams: 1 01970.pdf: 15439257 bytes, checksum: 0b1cf3bc75a8883bc2285242fe8dbcfd (MD5) / Dissertacao (Mestrado) / IPEN/D / Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP

We study the orientations of satellite galaxies in redMaPPer clusters constructed from the Sloan Digital Sky Survey at 0.1 < z < 0.35 to determine whether there is any preferential tendency for satellites to point radially towards cluster centres. We analyse the satellite alignment (SA) signal based on three shape measurement methods (re-Gaussianization, de Vaucouleurs, and isophotal shapes), which trace galaxy light profiles at different radii. The measured SA signal depends on these shape measurement methods. We detect the strongest SA signal in isophotal shapes, followed by de Vaucouleurs shapes. While no net SA signal is detected using re-Gaussianization shapes across the entire sample, the observed SA signal reaches a statistically significant level when limiting to a subsample of higher luminosity satellites. We further investigate the impact of noise, systematics, and real physical isophotal twisting effects in the comparison between the SA signal detected via different shape measurement methods. Unlike previous studies, which only consider the dependence of SA on a few parameters, here we explore a total of 17 galaxy and cluster properties, using a statistical model averaging technique to naturally account for parameter correlations and identify significant SA predictors. We find that the measured SA signal is strongest for satellites with the following characteristics: higher luminosity, smaller distance to the cluster centre, rounder in shape, higher bulge fraction, and distributed preferentially along the major axis directions of their centrals. Finally, we provide physical explanations for the identified dependences and discuss the connection to theories of SA.

In this thesis we study the interaction of supernova ejecta in the environment of young massive clusters. It has been already shown that winds of massive stars can be thermalized by mutual interactions inside the cluster and drive the strong star cluster wind. The SNe are, as discrete and extremely energetic events, in all ways diferent from the continuous stellar winds. This triggers the question under which parameter and if at all can the SNe ejecta interaction from a smooth star cluster wind. Therefore we at first parametrize the SNe explossions and based on the 3D simulations in FLASH we show for the first time that the convergence of the SNe ejecta interaction to a smooth star cluster wind is controlled by a single parameter ΠSN . The paramater ΠSN estimates the mean number of interacting SN ejecta based on a comparison of supernova rate and crossing time of SN ejecta in a cluster. For high enough values ΠSN > 1 the cluster is able to build up smooth a star cluster wind. This allows us to use a 1D semi-analytic code WINDCALC to calculate the cooling of the hot gas due to dust and estimate under which conditions the SNe-inserted matter is captured. This may explain the origin of so-called anomalous globular clusters. 1

In the formation of galaxy groups and clusters, the dark matter haloes containing satellite galaxies are expected to be tidally stripped in gravitational interactions with the host. We use galaxy-galaxy weak lensing to measure the average mass of dark matter haloes of satellite galaxies as a function of projected distance to the centre of the host, since stripping is expected to be greater for satellites closer to the centre of the cluster. We further classify the satellites according to their stellar mass: Assuming that the stellar component of the galaxy is less disrupted by tidal stripping, stellar mass can be used as a proxy of the infall mass. We study the stellar-to-halo mass relation of satellites as a function of the cluster-centric distance to measure tidal stripping. We use the shear catalogues of the Dark Energy Survey (DES) science verification archive, the Canada-France-Hawaii Lensing Survey (CFHTLenS) and the CFHT Stripe 82 surveys, and we select satellites from the redMaPPer catalogue of clusters. For galaxies located in the outskirts of clusters, we find a stellar-to-halo mass relation in good agreement with the theoretical expectations from Moster et al. for central galaxies. In the centre of the cluster, we find that this relation is shifted to smaller halo mass for a given stellar mass. We interpret this finding as further evidence for tidal stripping of dark matter haloes in high-density environments.

This thesis has focused on functionalising heterometallic [nPr2NH2][Cr7NiF8(O2CtBu)16], {Cr7Ni}, clusters, which are candidates for qubits in quantum information processing, by substitution of the peripheral carboxylic acids to produce [nPr2NH2][Cr7NiF8(O2CtBu)16-x(O2CR)], where R is a group with the desired functionality. The use of pyridyl and carboxylic acid containing groups has been investigated for the purposes of linking {Cr7Ni} units, either through metal sites and metallic clusters. The work has resulted in the synthesis of multi-component, polymetallic, nano-scale constructs where in some cases where the individual building blocks have been pre-synthesised and isolated prior to synthesis, with examples of three, four and six {Cr7Ni} units bound to a variety of metal clusters. A selection of aromatic functionalised carboxylic acids has also been successfully substituted onto the ring periphery with the prospect of binding to aromatic surfaces such as graphene and carbon nanotubes. These include fluorenylmethyloxycarbonyl protected amino acids, which opens a potential avenue to grafting of peptide chains to the periphery.

Une étude théorique couplée à une partie expérimentale a été entreprise sur la dynamique de l'échange de ligand sur des surfaces de nanoclusters (GNC) dans le but de montrer qu'il était possible de contrôler les propriétés structurales et optiques de GNC à travers la composition de la couronne de ligand. Nos études de calcul ont été effectuées par la théorie fonctionnelle de la densité en chimie quantique (approche Kohn - Sham). Nous avons analysé les principales caractéristiques UV - Visible des spectres calculés par TD - DFT / niveau de CAMB3LYP pour les clusters métalliques Au13, Au25 et Au28 protégées par des ligands thiolate, chlorure, et phosphine. Nos résultats montrent qu'il est possible de régler l'énergie de la bande d'absorption la plus basse des clusters d'or par une répartition spécifique des ligands qui contrôle de fait la répartition des charges entre la couronne de ligand et le noyau métallique.En parallèle, nous avons synthétisé une série de clusters de composition Au25 (ATP)x (TP) 18 - x avec 4ATP (4 - aminothiophénol) et TP (thiophénol) par synthèse directe et par échange de ligands. Les mesures de spectroscopie de masse ESI - MS montrent que la nucléarité Au25 est préservée pour tous ces différents clusters. En revanche, l'échange de ligands TP par le DDT (1 - dodécanethiol) dans le mélange conduit à la formation de nanoparticules. Les mesures de spectroscopies IR confirment la présence de deux ligands différents sur la surface de l'or et les analyses SAXS montrent que nous avons une bonne corrélation entre la distance entre deux cœurs métalliques et la longueur du ligand de surface. / We performed a joint computational – experimental investigation of the dynamics of ligand exchange on gold nanoclusters (GNC) surface with the aim to understand how to control the structural and optical properties of GNC through the design of their ligand shell. Our computational studies were carried out in the framework of the Kohn – Sham implementation of density functional theory in quantum chemistry. We analyzed the main features of UV – Vis spectra computed at the TD – DFT / CAMB3LYP level for the Au13, Au25, and Au28 metallic cores protected by thiolate, chloride, and phosphine ligands. Our results show that it is possible to tune the energy of the lowest absorption band of gold clusters by ligand shell engineering in order to control the charge redistribution between ligand shell and metallic core.In parallel we synthesized a set of Au25(ATP)x(TP)18 – x clusters with different ATP/TP ratios using an adapted Demessence protocol by combining 4ATP (4 – aminothiophenol) and TP (thiophenol) ligands. ESI – MS measurements evidence that for these mixed ligand shells the Au25 nuclearity is preserved. However, the addition of the DDT (1 – dodecanethiol) ligand in the mixture leads to nanoparticle formation. FT – IR spectroscopy confirms the absorption of two different ligands on the gold surface and SAXS shows that we have a good correlation between the distance between two clusters and the length of the ligand protecting them.Finally, we carried out a comparison of the mode of binding and the structural and optical properties of the fully ligated PH3 and NHC GNC with metallic cores of different nuclearities.