Ovakos induktionslinje i Hällefors består av induktionshärdning följt av induktionsanlöpning.  Släckningen vid härdningen sker med hjälp av duschar. Tidigare har Ovako använt sig av polymermedlet Aqua Tensid som släckningskoncentrat. I samband med användning av Aqua Tensid har kund upplevt förbättring i skärande bearbetning.  Användningen av Aqua Tensid har dock upphört p.g.a. arbetsmiljöproblem. Ovako har istället införskaffat Thermisol, ett annat polymermedel till släckningsprocessen. Detta arbete innehåller en utvärdering av Thermisol i Ovakos produktion då det tidigare inte gjorts. Test har utförts i induktionslinjen med släckning från rent vatten upp till en koncentrationshalt på 8,4% Thermisol. Testerna är utförda på stålsorten Ovako 356D. Från testerna har prov tagits ut och analyserats efter härdning samt efter anlöpning. Stängerna från testen har även följts upp i Ovakos svarvavdelning för att utvärdera om det uppstår skillnad i skärbarhet. De enbart härdade proverna visar på att prover släckta i Thermisol har större benägenhet till självanlöpning vid ytan. De resterande proverna visar inte på någon märkbar skillnad. Uppföljningen i svarv visar inte på någon skillnad i skärbarhet för stålsorten Ovako 356D.

En undersökning av inneslutningsbeteende under tillverkningsprocessen av götgjutet verktygsstål har utförts på Uddeholm i Hagfors. Med hjälp av OES med PDA och SEM med INCA feature undersöktes sammansättningen, antalet, storleken, fördelningen, koncentrationen och formen av inneslutningar före och efter vakuumbehandlingen samt i kokill.   Fyra typer av inneslutningar kunde identifieras i olika skeden i processen. Al2O3-MgO spineller i flytande CaO- Al2O3 lösning, CaO-Al2O3 flytande inneslutning, Al2O3-MgO Spineller och Al2O3-SiO2 i fastform.  Vakuumbehandlingen påverkar typen, formen, storleken och antalet inneslutningar. Den induktiva omrörningen påverkar antalet och storleken av inneslutningarna. Vid avgjutningen utskiljs Al2O3-SiO2 som med stor sannolikhet beror på provtagningen.

O trabalho apresentado aqui visou estudar a implantação de elementos em superfícies metálicas (particularmente cobre) de maneira controlada, investigando-se as alterações que tal implante causou na estrutura da superfície, objetivando uma possível melhoria no comportamento desses metais a serem utilizados como catodos em tochas de plasma ou para várias outras aplicações, tais como em catálise, micro eletrônica, oxidação e corrosão de metais e outros. Filmes finos de cobre policristalino foram implantados com íond (energia de 20KeV até 50KeV; doses da ordem de 10 15íons/cm2) de metais alcalinos (Li, Na, K, Rb e Cs) bem como de O e Cl. Foram realizadas diversas análises de superfície visando determinar as alterações ocorridas no cobre quando da implantação dos íons, tais como: composição de superfície (Auger Electron Spectroscopy, X-ray Photoelectron Spectroscopy), estrutura de superfícies em termos de topografia e do potencial de superfície (Kelvin Probe Force Microscopy), composição volumétrica X-ray Fluorescence, Rutherford Backscattering Spectroscopy e Energy Dispersive X-ray Spectroscopy), concentração de oxigênio (Elastic non-Rutherford Backscattering Spectroscopy) e estrutura cristalina (X-ray Diffraction). Modelos teóricos foram utilizados para se obter uma compreensão melhor das alterações estruturais que ocorrem durante a implantação iônica em uma superfície metálica (Stopping and Range of Ions in Matter e Tight-Binding Linear Muffin-Tin Orbital Atomic Sphere Approximation (Coherent Potential Approximation)). As análises de composição superficial mostraram que as concentrações dos elementos C, N, Cl e S dos substratos de cobre não implantados e implantados foram similares e que a única alteração na composição superficial, causada pelo processo da implantação iônica, foi a introdução dos íons desejados nos filmes de cobre. Observou-se que mesmo as pequenas doses de íons podem causar uma grande diminuição da função de trabalho (2-30%) em relação ao cubro puro; já a implantação de O e Cl gerou um aumento na função de trabalho de 300mV e 900MV, respectivamente. As concentrações detectadas de íons implantados de metais alcalinos podem ser consideradas altas (tendo em vista as doses de implantação relativamente pequenas, da ordem de 10.15ions/cm2) diminuindo rápido na direção do bulk das amostras; esta distribuição se deve provavelmente a um processo de migração de íons na direção da superfície. Os resultados de EBS e KPFM indicam que uma maior dose não necessariamente gera uma concentração maior de íons implantados na primeira camada superficial. Observou-se também que somente uma parte da dose total dos íons é efetivamente implantada, devido ao processo de sputtering, que ocorre durante a implantação iônica. A implantação iônica de diferentes íons alcalinos influencia diferentemente os processos de oxidação das amostras. A principal influência no aumento da oxidação é a estrutura topográfica das amostras; porém, a presença de íons implantados nas superfícies das amostras parece influenciar as etapas iniciais de oxidação, aumentando ou diminuindo a absorção de oxigênio. Para o caso da implantação dos íons de O e Cl, a concentração desses íons parece aumentar com a profundidade até um certo nível, o que, por sua vez, indica que não houve um processo de migração durante a implantação. Isto se deve provavelmente ao fato de que estes íons criam ligações com os elementos de substrato. As alterações da função de trabalho de dois casos distintos de deposição de metais (Ag e Cs) sobre Cu (111), foi estudada com o programa TB-LMTO-ASA (CPA), utilizando-se, nas simulações, valores diferentes para o raio de Wigner-Seitz para esferas vazias (WSES); os resultados das alterações da função de trabalho durante a deposição foram aproximadamente 20% menores em comparação com os valores experimentais da literatura. O efeito de WSES, que é, em princípio, um artefato computacional, sobre o valor da função de trabalho do sistema é normalmente interpretado como uma não confiabilidade dos modelos baseados nos conceitos de ASA. Porém, os resultados obtidos durante este trabalho indicam a existência de uma relação entre WSES e a rigorosidade da superfície; portanto, o sentido físico de esferas vazias pode ser visto como uma medida da rugosidade superficial. / In this work, the controlled implantation of the different elements in the metallic surfaces (particularly copper) was performed, in order to study the changes that the implantation causes on the surface structure, aiming to improve the behaviour of those metals for their use as cathodes in plasma torches or other applications, such as: catalysis, microelectronics, oxidation and corrosion of metals and others. Thin polycrystalline copper films were implanted with ions (energy 20-50keV; doses of order of \'10 POT. 15\' ions/\'cm POT. 2\') of alkaline metals (\'LI\', \'NA\', \'K\', \'RB\', and \'CS\') as well as of \'O\' and \'CL\'. Different surface analyses were performed in order to determine the changes on copper due to the ion implantation, in terms of: surface composition (Auger Electron Spectroscopy, X-ray Photoelectron Spectroscopy), topographic and surface potential structure (Kelvin Probe Force Microscopy), bulk composition (X-ray Fluorescence, Rutherford Backscattering Spectroscopy e Energy Dispersive X-ray Spectroscopy), oxygen concentration (Elastic non-Rutherford Backscattering Spectroscopy) and crystalline structure (X-ray Diffraction). Theoretical models were used to understand better the structural changes which occur on the metallic surface during the ion implantation process (Stopping and Range of Ions in Matter e Tight-Binding Linear Muffin-Tin Orbital Atomic Sphere Approximation (Coherent Potential Approximation)). The surface composition analyses of implanted and non-implanted copper substrates showed similar concentration of \'C\', \'N\', \'CL\' and \'S\' and that the only change in surface concentration, due to the ion implantation process, was the introduction of the desired ions in the surface of copper films. It was observed that even small ion doses can cause relatively large decrease of work function (2-30%) in relation to the pure copper value; the implantation of O and CL caused an increase in work function of 300m V and 900mV, respectively. The detected concentration of implanted alkali metal ions was relatively high (taking into consideration relatively small implantation doses, of the order of \'10 POT. 15\' ions/\'cm POT. 2\'), decreasing fast towards bulk of the samples; this distribution were probably caused by a migration process of implanted ions towards the surface. The EBS and KPFM results indicate that not always the largest dose produces the largest implanted ion concentration in the surface layer. It was also observed that only a part of the total ion dose is effectively implanted, due to the sputtering during the ion implantation process. Implantation of different alkali ions influences the sample oxidation process in a different way. The principal influence in the increase of oxidation is the topographic structure of the samples; however, the presence of the implanted ions on the samples surface seems to influence the initial stages of the oxidation, increasing or decreasing the oxygen adsorption. Of the cases of the O and CL implantation, the concentration of these ions seems to increase with depth, which indicates that there were no migration process involved. This is probably due to the fact that these ions create bonds with the substrate elements. The changes in the work function for two distinct cases of metal (AG and CS) deposition on CU (111) was studied with the computational programme TB-LMTO-ASA (CPA), using, in the simulations, different values for the Wigner-Seitz radius for Empty Spheres (\'WS IND. ES\'); the results on the work function changes during the deposition were approximately 20% lower in comparison with the experimental data from the literature. The effect of \'WS IND. ES\', which is, in principle, a computation artefact, on the work function value of the studied systems is normally interpreted as the non-reliability of the models based on the ASA concepts. However, the results obtained during this work indicate that there is a relation between the \'WS IND. ES\' and the surface roughness; therefore, physical meaning of the empty spheres can be understood as a \"measure\" of surface roughness.

Vidros metálicos maciços fazem parte de um novo grupo de materiais de características distintas das ligas metálicas convencionais. O processamento dessas ligas ainda não foi bem consolidado nos centros de pesquisa brasileiros devido à dificuldade de processamento. Este trabalho descreve o desenvolvimento de um sistema de síntese e coquilhamento para a obtenção de vidros metálicos maciços. O sistema foi avaliado quanto ao desempenho e repetibilidade das amostras. A liga Cu46Zr42Al7Y5, formadora de vidro, foi processada e analisada através da caracterização por difração de raios-X (DRX), calorimetria exploratória diferencial (DSC) e microscopia eletrônica de varredura (MEV). Foram obtidas duas amostras com estrutura totalmente amorfa em espessuras médias de até 1,5 mm e uma amostra com aproximadamente 5,5 mm de espessura amorfa. A temperatura de transição vítrea observada foi igual às relatadas na literatura científica. Assim, o sistema desenvolvido mostrou-se eficiente para o controle da atmosfera, resfriamento rápido das amostras e outras variáveis que são obrigatórias para o sucesso na formação de estruturas amorfas em ligas por fundição. / Bulk metallic glasses are new materials with different features in comparison with conventional metallic alloys. The processing techniques of such alloys are still not consolidated in Brazilian research centers because of inherent processing difficulties. This work describes the development of a system for the synthesis and casting of bulk metallic glassy samples. The system was evaluated by its performance and alloys repeatability. The Cu46Zr42Al7Y5 alloy was processed and analyzed for the formation of amorphous structure through X-ray diffraction (XRD), differential scanning calorimetry (DSC) and scanning electron microscopy (SEM). It was produced two samples with fully amorphous structure at average thickness of 1.5 mm and one sample reaching around 5.5 mm of fully glassy structure. The same glass transition temperature reported on scientific literature was found in the alloys processed in the present work. Thus, the system has shown efficiency on atmosphere control, sample quenching and others important variables that are, by default, necessary to succeed in amorphous structure formation.

了解表面等子體和外部環境之間的相互作用對表面等子體應用的開發非常重要。我們的研究集中在表面等子體與遠場的耦合，以及表面等子體模之間的耦合。 / 首先，我們研究由表面等子體模式耦合所產生的射衰變的變化。我們以角分辨反射光譜測同孔大小的納米孔陣上的簡併表面等子體模的衰減。對於每個孔的大小，我們觀察到在發生共振耦合的光譜區，衰減速有很大的改變，顯示出暗模和模的形成。耦合模很好地解釋衰變的變化。推導出的耦合常隨著孔直徑的增加而增加。我們也對耦合模一些有趣的特性及衰減變化的微觀起源進探討。 / 第二，我們以偏振分辨反射光譜從二維屬陣射散射。我們發現，反射光譜遵循的法模型可以由耦合模和瓊斯矩陣演算推導出。通過用正交方向的偏光器和分析器，反射光譜上的谷翻轉成峰，從以能夠測定出射散射效。我們發現，射散射效與波長和孔直徑的依賴關係和單孔的瑞散射相符合。 / 最後，我們開發一個新的方法，以偏振分辨光譜在實驗中測射衰變。這方法的有效性通過時域有限差分計算得到證明。我們還將此方法應用在實驗據上作為示範。 / Understanding the interaction between surface plasmon and outer environment is crucial in development of plasmonic applications. Our study is focused on the coupling between surface plasmons and far field, and also the coupling between surface plasmon modes. / First, we studied the change in radiative decay rate due to coupling of degenerate surface plasmon modes. We measured the decay rates of two degenerate surface plasmon modes in Au nanohole arrays with different hole sizes by angle-resolved reflectivity spectroscopy. For each hole size, at the spectral region where resonant coupling occurs, we observed a large modification in decay rates, leading to the formation of dark and bright modes. The change in decay rates is well explained by coupled-mode theory. The deduced coupling constant is found to increase with increasing hole diameter. Interesting properties of the coupled modes and microscopic origin of the change in decay rate is also discussed. / Second, we measured the radiative scattering from two-dimensional metallic arrays by using polarization-resolved reflectivity spectroscopy. We found that the reflectivity spectra follow the Fano-like model which can be derived from coupled-mode theory and Jones matrix calculus. By orthogonally orienting the incident polarizer and the detection analyzer, reflectivity dips flip into peaks and the radiative scattering efficiency can be determined accordingly. The dependence of total radiative scattering efficiency on wavelength and hole diameter is found to agree well with Rayleigh scattering by single hole. / Finally, we developed a new method to measure radiative decay rates experimentally by polarization-resolved reflectivity spectroscopy. The validity of this method is proved by finite-difference time-domain simulation. We also applied this method on experimental data as a demonstration. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Lo, Hau Yung = 表面等離子體在金屬納米孔陣列的輻射衰減及耦合 / 羅孝勇. / "December 2012." / Thesis (M.Phil.)--Chinese University of Hong Kong, 2013. / Includes bibliographical references (leaves 88-92). / Abstracts also in Chinese. / Lo, Hau Yung = Biao mian deng li zi ti zai jin shu na mi kong zhen lie de fu she shuai jian ji ou he / Luo Xiaoyong. / Chapter 1 --- Introduction --- p.1 / Chapter 2 --- Basic Theory and Techniques --- p.3 / Chapter 2.1 --- Macroscopic Maxwell Equations and Boundary Conditions --- p.3 / Chapter 2.2 --- Symmetries and Band Structure --- p.4 / Chapter 2.3 --- Coupled-mode Theory --- p.10 / Chapter 2.4 --- Finite-difference Time-domain Simulation --- p.12 / Chapter 2.5 --- Preparation of Metallic Nano-hole Arrays --- p.14 / Chapter 3 --- Fundamentals of Surface Plasmons on Metallic Nanohole Array --- p.18 / Chapter 3.1 --- Confinement and Propagation Nature of SPs --- p.18 / Chapter 3.2 --- Skin Depth and Propagation Length --- p.19 / Chapter 3.3 --- Dispersion Relation and Phase-matching Conditions --- p.21 / Chapter 3.4 --- Measurement of Band Structure: Angle-resolved Reflectivity Mapping --- p.23 / Chapter 3.5 --- Red Shift of Band Structure --- p.26 / Chapter 3.6 --- Comparison of Two Presentations of Band Structure: "ω against k" versus "λ against θ" --- p.28 / Chapter 3.7 --- Resonance Peak Shape: FanoModel and Wood's Anomalus --- p.30 / Chapter 3.8 --- Resonance Peak Shape: "Fano-like" Model --- p.34 / Chapter 3.9 --- Appendix A: Derivation of Eq(3.1) --- p.36 / Chapter 4 --- Decay Rates Modification though Coupling of Degenerate Surface Plasmon modes --- p.40 / Chapter 4.1 --- Introduction --- p.40 / Chapter 4.2 --- Measurements of Degenerate Surface Plasmon Modes --- p.42 / Chapter 4.3 --- Decay rates of Coupled Modes --- p.45 / Chapter 4.4 --- Hole Diameter Dependence of Coupling Constants --- p.47 / Chapter 4.5 --- Understanding the S-polarized Surface Plasmon Modes --- p.50 / Chapter 4.6 --- TE-like Surface Plasmon Modes --- p.53 / Chapter 4.7 --- Microscopic Origin of the Modification in Decay Rate --- p.54 / Chapter 4.8 --- Summary --- p.60 / Chapter 5 --- Direct Measurement of Radiative Scattering of Surface Plasmon Resonance from Metallic Arrays by Polarization-resolved Reflectivity Spectroscopy --- p.61 / Chapter 5.1 --- Introduction --- p.61 / Chapter 5.2 --- Theory of Direct Measurement of Radiative Scattering --- p.62 / Chapter 5.3 --- Comparison with Experiment --- p.65 / Chapter 5.4 --- Comparison with Rayleigh Scattering Model --- p.71 / Chapter 5.5 --- Summary --- p.74 / Chapter 6 --- A Method of Obtaining Radiative Decay Rates From Experiment --- p.76 / Chapter 6.1 --- Introduction --- p.76 / Chapter 6.2 --- Method --- p.77 / Chapter 6.3 --- Prove of Validity --- p.78 / Chapter 6.4 --- Experimental Demonstration --- p.82 / Chapter 6.5 --- Summary --- p.85 / Chapter 7 --- Conclusion --- p.86 / Chapter 8 --- Bibliography --- p.88 / Chapter 9 --- Curriculum Vitae --- p.93

by Ong Chung Wo. / Title also in Chinese. / Thesis (Ph.D.)--Chinese University of Hong Kong. / Bibliography: leaves 258-263. / Acknowledgements / Abstract / Table of Contents / Chapter Chapter 1 --- Introduction --- p.1 / Chapter Chapter 2 --- Sample Preparation --- p.6 / Chapter A. --- General Review of Chemical Vapour Deposition Technique --- p.6 / Chapter B. --- Our Deposition System --- p.9 / Chapter B.1 --- General Description --- p.9 / Chapter B.2 --- Induction Heater --- p.10 / Chapter B.3 --- Graphite Susceptor --- p.12 / Chapter B.4 --- Safety --- p.13 / Chapter C. --- Sample Description --- p.16 / Chapter Chapter 3 --- Thickness Measurement --- p.26 / Chapter Chapter 4 --- Composition Analysis --- p.29 / Chapter A. --- Introduction --- p.29 / Chapter B. --- Composition Analysis of Boron-Silicon Films Using EDX --- p.32 / Chapter B.1 --- Experimental Method --- p.32 / Chapter B.2 --- Requirement on Film Thickness and Preparation of Unsupported Films --- p.33 / Chapter B.3 --- Possible Applications and Limitations of Our Method --- p.35 / Chapter B.4 --- Results --- p.35 / Chapter Chapter 5 --- X-ray Diffraction Experiment --- p.42 / Chapter A. --- Introduction --- p.42 / Chapter B. --- Structures of Boron and Silicon-Boron Compounds --- p.43 / Chapter B.1 --- B12 Icosahedron and Three-Center Two-Electron Bond --- p.43 / Chapter B.2 --- Polymorphism of Crystalline Boron --- p.44 / Chapter B.2.1 --- α-Rhombohedral Boron --- p.44 / Chapter B.2.2 --- β-Rhombohedral Boron --- p.45 / Chapter B.2.3 --- Amorphous Boron --- p.47 / Chapter B.3 --- Structures of Crystalline Boron-Silicon Compounds --- p.48 / Chapter C. --- X-ray Diffraction Experiment --- p.50 / Chapter C.1 --- Experimental Technique --- p.50 / Chapter C.2 --- Analysis of X-Ray Diffraction Pattern --- p.50 / Chapter D. --- Results and Discussion --- p.51 / Chapter D.1 --- Boron Films --- p.51 / Chapter D.2 --- Boron-Silicon Films --- p.57 / Chapter Chapter 6 --- Infrared Absorption Experiment --- p.84 / Chapter A. --- Experimental Method --- p.84 / Chapter B. --- Results --- p.87 / Chapter C. --- Discussion --- p.88 / Chapter C.1 --- Analysis of Boron Films --- p.88 / Chapter C.1.1 --- Indentification of Three Absorption Bands --- p.88 / Chapter C.1.2 --- Effect of Substrate Temperature --- p.91 / Chapter C.2 --- Analysis of Boron-Silicon Films --- p.92 / Chapter C.2.1 --- Effect of Substrate Temperature --- p.92 / Chapter C.2.2 --- Effect of Silicon Incorporation --- p.93 / Chapter C.2.3 --- Existence of Icosahedral Clusters --- p.94 / Chapter C.3 --- Comparative Study of Deposition Mechanism Between Thermal CVD Method and Glow Discharge Method --- p.94 / Chapter Chapter 7 --- Microhardness and Surface Morphology --- p.111 / Chapter A. --- Measuring Techniques --- p.111 / Chapter B. --- Microhardness Measurement --- p.113 / Chapter B.1 --- Boron Films --- p.113 / Chapter B.2 --- Boron-Silicon Films --- p.114 / Chapter C. --- Surface Morphology --- p.114 / Chapter C.1 --- Boron Films --- p.114 / Chapter C.2 --- Boron-Silicon Films --- p.115 / Chapter Chapter 8 --- Optical Absorption Experiment --- p.127 / Chapter A. --- Introduction --- p.127 / Chapter B. --- Theory of Optical Absorption --- p.128 / Chapter B.1 --- Absorption of Crystalline Materials --- p.129 / Chapter B.2 --- Optical Absorption of Amorphous Materials --- p.132 / Chapter C. --- Results --- p.135 / Chapter C.1 --- Boron Films --- p.135 / Chapter C.2 --- Boron-Silicon Films --- p.136 / Chapter D. --- Analysis --- p.138 / Chapter D.1 --- Band Models --- p.138 / Chapter D.2 --- Deconvolution of Absorption Spectra --- p.140 / Chapter D.2.1 --- Deconvolution of Absorption Spectra of Boron Films --- p.141 / Chapter D.2.2 --- Deconvolution of Absorption Spectra of Boron-Silicon Films --- p.144 / Chapter D.2.3 --- Results --- p.146 / Chapter E. --- Discussion --- p.149 / Chapter Chapter 9 --- Conductivity and Thermoelectric Power Measurements --- p.203 / Chapter A. --- Transport Mechanism in Amorphous Semiconductors --- p.203 / Chapter A.1 --- Band Models of Amorphous Semiconductors --- p.203 / Chapter A.2 --- Electrical Conductivity and Thermoelectric Power --- p.205 / Chapter B. --- Experimental Methods --- p.208 / Chapter C. --- Results --- p.209 / Chapter C.1 --- Boron Films --- p.209 / Chapter C.2 --- Boron-Silicon Films --- p.210 / Chapter D. --- Discussion --- p.212 / Chapter D.1 --- Boron Films --- p.212 / Chapter D.2 --- Boron-Silicon Films --- p.213 / Chapter Chapter 10 --- Electron Spin Resonance --- p.230 / Chapter A. --- Introduction --- p.230 / Chapter B. --- Experimental Method --- p.231 / Chapter C. --- Results --- p.231 / Chapter C.1 --- Boron Films --- p.231 / Chapter C.2 --- Boron-Silicon Deposited at 300°C --- p.232 / Chapter C.3 --- Boron-Silicon Deposited at 460 and 620°C --- p.233 / Chapter D. --- Discussion --- p.235 / Chapter D.1 --- Boron Films --- p.235 / Chapter D.2 --- Boron-Silicon Films --- p.237 / Chapter Chapter 11 --- Conclusion --- p.254 / Chapter A. --- Structure --- p.254 / Chapter B. --- Mechanical Properties --- p.256 / Chapter C. --- Optical Absorption and Density of States --- p.256 / Chapter D. --- Electrical Properties --- p.257 / References --- p.258

No presente trabalho foram realizados estudos da atividade biológica de complexos imínicos de Cu(II) e Zn(II) derivados da isatina, principalmente frente a células tumorais HeLa. Sabe-se que estes complexos se ligam ao DNA, podendo causar clivagens simples e duplas na sua estrutura, em presença de peróxido de hidrogênio, através de um mecanismo predominantemente oxidativo. Os complexos de Cu(II) geram espécies reativas de oxigênio (EROs) e, além disto, atuam sobre a mitocôndria como agentes desacopladores. Sabe-se ainda que esses compostos interagem com proteínas específicas, como por exemplo a topoisomerase humana IB e as quinases dependentes de ciclinas (CDKs), inibindo significativamente sua atividade, ou a proteassoma, frente à qual apenas uma inibição moderada foi observada. Os ensaios in vitro desenvolvidos nesta tese, permitiram evidenciar a capacidade de os complexos de intercalar no DNA e RNA, além de clivar o primeiro biopolímero. Os resultados obtidos in celullo, evidenciaram a dependência do cobre para a citotoxicidade dos complexos sendo estes compostos capazes de estimular a necrose das células HeLa. Além disso, os resultados demonstraram que estes compostos são capazes de interferir no ciclo celular, interrompendo-o em fase G2/M e de desencadear um desequilíbrio oxidativo. Os principais alvos intracelulares dos complexos, em células HeLa, são a Mitocôndria, pois interferem em seu funcionamento diminuindo o seu potencial de membrana, e o DNA clivando-o. Ademais, pretendeu-se, através de um estudo sistemático por microscopia Raman confocal, identificar danos celulares provocados pelos complexos, especialmente uma grande alteração no núcleo celular de células HeLa após o tratamento com o complexo [Cu(isaepy)]+. Através de ensaios de viabilidade, também foi possível demonstrar que a superexpressão de glicoproteína-P para linhagem MES-AS/Dx5 não resulta na resistência dessas células frente aos compostos testados, e que os complexos não interferem no funcionamento desta glicoproteína. Também foi observado, através dos experimentos com células HaCaT, que o complexo [Zn(isaepy)]2+ é capaz de interferir no ciclo autofágico celular. / In the present work, the synthesis and characterization of oxindolimine complexes of Cu(II) and Zn(II) were carried out. R is known that these complexes bind to DNA and can cause single and double cleavages in their structure, in the presence or absence of hydrogen peroxide, through a predominantly oxidative mechanism. Cu(II) complexes generate reactive oxygen species (ROS) and, in addition, act on mitochondria as decoupling agents. These compounds are also known to interact with specific proteins, such as human topoisomerase IB and cyclin-dependent kinases (CDKs), inhibiting significantly their activity, or the proteasome, against which only moderate inhibition has been observed. The in vitro assays developed in this thesis have demonstrated the ability of these complexes in intercalating at DNA and RNA, in addition to cleaving the first biopolymer. The results in cellulo evidenced the dependence on the copper for the cytotoxicity of the complexes, that can stimulate the necrosis in HeLa cells. In addition, the results demonstrated that these compounds are capable of interfering in the cell cycle, stopping it at G2/M phase and triggering an oxidative imbalance. The main intracellular targets of the complexes, in HeLa cells, are the Mitochondria, where they interfere in its function, diminishing its membrane potential, and the DNA, causing its cleavage. Further, it was intended, through a systematic study by confocal Raman microscopy, to identify cellular damage triggered by the complexes. Particularly, a large change in the cell nucleus of HeLa cells was demonstrated after treatment with the \'[Cu(isaepy)] POT.+\' complex. Through viability assays, it was also demonstrated that overexpression of P-glycoprotein in MES-SA/Dx5 lineage does not result in the resistance of these cells to the tested compounds, and that the complexes do not interfere in the functioning of this glycoprotein. Finally, it was observed, in experiments with HaCaT cells, that \'[Zn(isaepy)] POT.2+\' complex can interfere in the autophagic cell cycle.

"The time-of-arrival (ToA)-based localization technique performs superior in line-of-sight (LoS) conditions, and its accuracy degrades drastically in proximity of micro-metals and human body, when LoS conditions are not met. This calls for modeling and formulation of Direct Path (DP) to help with mitigation of ranging error. However, the current propagation tools and models are mainly designed for telecommunication applications via focus on delay spread of wireless channel profile, whereas ToA-based localization strive for modeling of DP component. This thesis provides a mitigation to the limitation of existing propagation tools and models to computationally capture the effects of micro-metals and human body on ToA-based indoor localization. Solutions for each computational technique are validated by empirical measurements using Ultra-Wide-Band (UWB) signals. Finite- Difference-Time-Domain (FDTD) numerical method is used to estimate the ranging errors, and a combination of Uniform-Theory-of-Diffraction (UTD) ray theory and geometrical ray optics properties are utilized to model the path-loss and the ToA of the DP obstructed by micro- metals. Analytical UTD ray theory and geometrical ray optics properties are exploited to model the path-loss and the ToA of the first path obstructed by the human body for the scattering scenarios. The proposed scattering solution expanded to analytically model the path-loss and ToA of the DP obstructed by human body in angular motion for the radiation scenarios."

Thesis. 1977. Ph.D.--Massachusetts Institute of Technology. Dept. of Materials Science and Engineering. / MICROFICHE COPY AVAILABLE IN ARCHIVES AND SCIENCE. / Vita. / Includes bibliographical references. / Ph.D.

Neste trabalho desenvolveu-se um sensor eletroquímico a partir da modificação de superfície de um eletrodo de carbono vítreo com nanopartículas metálicas de Pt e intermetálicas de NiSb suportadas em carbono Vulcan® XC72. Tal modificação visou à obtenção de um sensor de baixo custo, simples e rápido para determinação do cloridrato de tetraciclina (TTC). A tetraciclina é um fármaco com propriedades antibióticas amplamente utilizado na saúde humana e animal devido sua baixa toxicidade e fácil obtenção. A modificação de superfície do eletrodo de trabalho foi realizada a partir da adição de uma suspensão das nanopartículas em dimetilformamida (DMF) (1 mg/1 mL) sobre a superfície do eletrodo previamente limpo e os estudos voltamétricos conduzidos utilizando as técnicas de voltametria cíclica, voltametria de pulso diferencial e cronoamperometria. Como consequência dos resultados obtidos, prosseguiu-se apenas com os estudos da nanopartícula de Pt na construção de um sensor para determinação da TTC. As nanopartículas apresentam propriedades diferentes daquelas exibidas pelo mesmo material quando estes se encontram em partículas de maior tamanho como bulks, e dentre suas principais características, o aumento da área superficial provocado pela modificação do eletrodo mostrou resultados promissores na detecção e quantificação do analito. Após diversos estudos sobre o eletrólito de suporte e o pH, obteve-se a melhor resposta voltamétrica em solução de tampão fosfato 0,10 mol L-1 pH 3,0 através da voltametria cíclica tanto na determinação do analito em água purificada quanto na determinação em urina sintética. O eletrodo modificado com nanopartículas de Pt apresentou resposta linear na faixa de 9,99 e 44,01 µmol L-1, limite de detecção 4,28 µmol L-1 e limite de quantificação 14,26 µmol L-1. A aplicação do eletrodo em uma amostra de urina sintética ocorreu com sucesso, alcançando um valor de concentração com diferença de 3% para o valor real. / In this work it was developed an electrochemical sensor by the surface modification of a glassy carbon electrode with metallic Pt nanoparticles and intermetallic NiSb nanoparticles in Vulcan® XC72 carbon as the support. Such surface modification sought to obtain a low cost sensor, easy to work and quick working to determine tetracycline hydrochloride. The tetracycline is a drug with antibiotics properties widely used in human and animal treatment due to its low toxicity and easy obtainability. The surface modification of the work electrode was accomplished through the addition of a suspension of the nanoparticles in dimethylformamide (1 mg/1 mL) in the electrode surface previously cleaned and the voltammetric studies conducted with the use of techniques such as cyclic voltammetry, differential pulse voltammetry and chronoamperometry. As a consequence of the obtained results, only the studies with the sensor developed with Pt nanoparticles were continued for the tetracycline determination. The nanoparticles presents different properties of those shown by the same material when these are in bigger forms, such as bulks and among the main characteristic, the superficial area increase caused by the electrode modification shown promising results for the detection and quantification of the analyte. After several studies about the supporting electrolyte and the pH, it was obtained a better voltammetric response in phosphate buffer solution 0.1 mol L-1 and pH 3.0 for the determination of the analyte in purified water and synthetic urine. The modified electrode with metallic Pt nanoparticles had a linear response in the range 9.99 to 44.01 µmol L-1 with a detection limit of 4.28 µmol L-1 and quantification limit of 14.26 µmol L-1. The electrode application in a synthetic urine sample was a success, reaching concentration values with a difference within 3% of the real value.