Varias técnicas de física nuclear tem sido aplicadas no estudo de artefatos arqueológicos e de arte contribuindo para seu restauro e preservação. A aplicação destas técnicas são indicadas por não serem destrutivas, preservando o material a ser analisado. Neste trabalho, propomos um procedimento para a investigação indireta da dureza de espadas antigas, por meio de técnicas não destrutivas. Com este proposito as técnicas PIXE, NRA, XRD e RBS se adequam ao nosso estudo de espadas antigas, especificamente uma espada Indiana (Damascena) e outra Japonesa (Wakizashi). Com a técnica PIXE esperávamos identificar os elementos presentes nas laminas das espadas e em suas empunhaduras. Na espada Indiana os elementos identificados foram: Cr, Mn, Fe, Ni, Cu, Zn e As. Para a espada Japonesa somente o elemento Fe foi identificado, mas com o auxílio da técnica RBS identificamos também, um filme fino de carbono na superfície da lamina, medindo 0; 75 _m de espessura. Nas empunhaduras foram identificados os elementos Cr, Fe, Cu e Au para a espada Indiana; Fe, Cu, As e Ag na peca Habaki e S, Cl, K, CA, Fe, As e Au na peca Fuchi, estas duas pecas fazem parte da empunhadura da espada Japonesa. A técnica XRD foi usada para verificarmos as estruturas cristalinas que se formam na superfície das laminas durante o processo de forja (variação de 6 temperatura e deformações plástica). Estas informações possibilitam inferir sobre a temperatura de forja e consequências da deformação plásticas. A fase cristalina da superfície das laminas foi identificada como ferro na forma cristalina cubica de corpo centrado. Nesta estrutura, ha a formação de pequenos cristais orientados (cristalitos), que apresentaram tamanho médio da ordem de 200 _A. Foi verificado que ha também uma fase amorfa do ferro na espada Japonesa, sugerindo que o processo de forja alcançou temperaturas menores quando comparada com a espada Indiana. A espada Damascena _e muito famosa pela dureza e ductibilidade apresentada por sua lamina. Um elemento que pode contribuir para estas caraterísticas e o nitrogênio, que pode ser identificado usando a técnica NRA, mais especificamente a reação 15N(p; _)12C. O nitrogênio poderia ser introduzido na lamina durante o processo de endurecimento da região de corte. Neste processo a lamina era resfriada em urina animal, composta principalmente por acido úrico (C5H4N4O3) e ureia (NH2)2CO. Não foi possível identificarmos a presença de nitrogênio dentro do nosso limite de detecção (acima de 0; 263(4)% em massa de nitrogênio, valor referenciado para a amostra padrão CRM-298). / A set of physical techniques have been applied to characterize archaeological and art artifacts and contribute to its preservation and restoration. The application of these techniques are indicated because they are non invasive methods, preserving the material to be analyzed. In this work, we propose a procedure to investigate indirectly the hardness of ancient swords, by nondestructive techniques. With this aim, we decided to apply the techniques PIXE, NRA, XRD and RBS in the study of ancient swords, specially Indian (Damascus blade) and a Japanese (Wakizashi) swords. With PIXE we identified the major compounds in the blades and in their grips. In the Indian blade were identified the following elements: Cr, Mn, Fe, Ni, Cu, Zn e As. In the Japanese only iron was identified, although, with RBS we could identified a thin _lm of carbon on its surface. The grips were also analyzed and the results indicated to Indian were: Cr, Fe, Cu and Au; and to Japanese: Fe, Cu, As e Ag in the peace Habaki, and S, Cl, K, CA, Fe, As e Au in the peace Fuchi, those pieces are part of the grip. The XRD technique was applied to verify the crystalline structure which were formed during the forging process (hammering and quenching). These information can help to understand more about the quenching and hammering process. The crystalline phase in the surface of the blade was identified as iron. The surface is composed by crystallites oriented with grain size in order to 200_A, oriented as the result of hammering process. Also there is an amorphous phase in the Japanese blade, suggesting that in the forje process the temperature achieved was lower when compared with the Indian sword. The Damascus blade is famous due its hardness and ductility. An element that can improve these characteristics is the nitrogen. Its determination is possible using NRA technique, more specially the reaction 15N(p; _)12C. The nitrogen could been insert in the blade during the edge hardness process (in this process the blade was quenched into animal urine that its main compound are uric acid (C5H4N4O3) and urea (NH2)2CO, or in a brine). It was not possible to identify the presence of nitrogen within our limit of quantification.

Mémoire numérisé par la Direction des bibliothèques de l'Université de Montréal.

SiC has become an attractive wide bandgap semiconductor due to its unique physical and electronic properties and is widely used in high temperature, high frequency, high power and radiation resistant applications. SiC has been used as an alternative to Si in harsh environments such as in the oil industry, nuclear power systems, aeronautical, and space applications. SiC is also known for its polytypism and among them 3C-SiC, 4H-SiC and 6H-SiC are the most common polytypes used for research purposes. Among these polytypes 4H-SiC is gaining importance due to its easy commercial availability with a large bandgap of 3.26 eV at room temperature. Controlled creation of defects in materials is an approach to modify the electronic properties in a way that new functionality may result. SiC is a promising candidate for defect-induced magnetism on which spintronic devices could be developed. The defects considered are of room temperature stable vacancy types, eliminating the need for magnetic impurities, which easily diffuse at room temperature. Impurity free vacancy type defects can be created by implanting the host atoms of silicon or carbon. The implantation fluence determines the defect density, which is a critical parameter for defect induced magnetism. Therefore, we have studied the influence of low fluence low energy silicon and carbon implantation on the creation of defects in n-type 4H-SiC. The characterization of the defects in these implanted samples was performed using the techniques, RBS-channeling and Raman spectroscopy. We have also utilized these characterization techniques to analyze defects created in much deeper layers of the SiC due to implantation of high energy nitrogen ions. The experimentally determined depths of the Si damage peaks due to low energy (60 keV) Si and C ions with low fluences (< 1015 cm-2) are consistent with the SRIM-2011 simulations. From RBS-C Si sub-lattice measurements for different fluences (1.1×1014 cm-2 to 3.2×1014 cm-2) of Si implantation in 4H-SiC, the Si vacancy density is estimated to range from 1.29×1022 cm-3 to 4.57×1022 cm-2, corresponding to average vacancy distances of 4.26 Å to 2.79 Å at the damage peak (50±5 nm). Similarly, for C implanted fluences (1.85×1014 cm-2 to 1×1015 cm-2), the Si vacancy density varies from 1.37×1022 cm-3 to 4.22×1022 cm-3 with the average vacancy distances from 4.17 Å to 2.87 Å at the damage peak (110±10 nm). From the Raman spectroscopy, the implantation-induced lattice disorders calculated along the c-axis (LO mode) and perpendicular to c-axis (TO mode) in 4H-SiC are found to be similar. Furthermore, the results obtained from SQUID measurements in C implanted n-type 4H-SiC sample with fluences ranging from 1×1012 to 1.7×1016 ions/cm2 have been discussed. The implanted samples showed diamagnetism similar to the unimplanted sample. To date, to our best of knowledge, no experimental work has been reported on investigating defect induced magnetism for self-ion implantation in n-type 4H-SiC. These first reports of experimental results can provide useful information in future studies for a better understanding of self-ion implantation in SiC-based DMS.

Im Rahmen dieser Diplomarbeit wurden Si(001)-Oberflächen mit Selen modifiziert und anschließend charakterisiert. Die Herstellung der Selenpassivierungsschichten wurde in einer MBE-Anlage durchgeführt. Die Charakterisierung erfolgte durch RHEED-, LEED- und RBS-Untersuchungen.

At the Tandem accelerator in the Ångström laboratory, Uppsala, Rutherford backscattering spectrometry (RBS) is one of the methods used for thin film analysis, providing information on thickness and composition. The films are commonly grown on silicon substrates, whose crystal structure gives rise to channelling effects (a strong angular dependence in the intensity of the signal), which can cause faulty results. For other samples, channelling may also be used to get information on crystal structure and quality. This work demonstrates new functions to the existing software, aiming at minimizing these effects. The new methods have been tested by measurements both in channelling directions and in directions determined by the old method. In comparison with the earlier method the worst-case error is of order 80 %,commonly around 20 %, but it is possible to achieve an error which is not detectable. It is worth to note that the stated errors appear in tests oriented for maximum channelling, where effects without the new methods give an error corresponding to an apparent thin-film thickness almost 18 times that of the actual thickness. / Vid Tandemlabbet i Ångströmlaboratoriet, Uppsala, används bland annat Rutherford backscattering spectrometry (RBS) för att undersöka egenskaper, t.ex tjocklek och sammansättning, hos tunnfilmer som ofta är odlade på kiselsubstrat. Kiselkristallernas struktur ger upphov till kanaliseringseffekter, d.v.s starkt vinkelberoende intensitet, som i detta sammanhang kan ge felaktiga resultat. För andra prover kan kanaliseringseffekter användas för att få information om kristallstruktur och kvalitet. I det här arbetet demonstreras nyskrivna funktioner till befintlig mjukvara med syfte att minimera dessa effekter. De nya funktionerna har testats genom provtagningar i orienteringar som är gynnsamma och icke gynnsamma för kanalisering. Vid jämförelse med tidigare metoder ger de nya metoderna ett fel på i värsta fall ca. 80%, med bättre parametrar sjunker felet till ca 20 % och med rätt val av parametrar försvinner felet jämfört med tidigare metod. Värt att notera är att ovanstående maximala fel uppstår vid test orienterat för maximal kanalisering, där effekterna utan de nya metoderna ger ett fel på uppemot en faktor 18.

This thesis is on the study of the characterization of interfaces and surfaces of high-k stacks for the future microelectronics. The changes of the high-k stacks during thermal processing and its mechanism have been experimentally investigated by high-resolution Rutherford Backscattering Spectrometry (HRBS) in combination with isotope tracing. The experimental results are consistent with the theoretical prediction that the silicon will be emitted outward to release the stress which is induced by the interface Si oxidation. Then, we studied the potential method, oxygen-gettering by Ti overlayer, for controlling the interface SiO2 thickness. Furthermore, we proposed a Time-Of-Flight (TOF) detector system for application on crystallographic analysis. TOF-RBS system is capable to analyze the sample’s crystallographic and chemical information even at the near surface of the sample, which is strongly required by the future microelectronics industry. In this chapter, brief introduction to the high-k stacks and the outline of this thesis are described. / Kyoto University (京都大学) / 0048 / 新制・課程博士 / 博士(工学) / 甲第13814号 / 工博第2918号 / 新制||工||1431(附属図書館) / 26030 / UT51-2008-C730 / 京都大学大学院工学研究科マイクロエンジニアリング専攻 / (主査)教授 木村 健二, 教授 斧 髙一, 教授 立花 明知 / 学位規則第4条第1項該当

Kyoto University (京都大学) / 0048 / 新制・論文博士 / 博士(工学) / 乙第12399号 / 論工博第4030号 / 新制||工||1477(附属図書館) / 27429 / UT51-2009-M905 / 京都大学大学院工学研究科機械物理工学専攻 / (主査)教授 木村 健二, 教授 井手 亜里, 教授 河合 潤 / 学位規則第4条第2項該当

This study has addressed a central issue, a gap in our existing knowledge, literature, analysis, an understanding of the role of state in resource seeking. Whilst the role and operations of the firm, has long been a primary focus of research in Strategic Management, analysis of the role and influence of the state with respect to firms has been relatively under-researched. To investigate this core research question, the study identified and applied the well-established theoretical and methodological approach, the Resource Based View of the ‘firm’ (RBV), developing it further to incorporate and mainstream the factor of the state and elaborating a fresh analytical approach, termed the resource-based view of the ‘state’ (RBS). The new RBS conceptual framework has been proposed by extending the central proposition of the RBV of the firm- that a firm must acquire and control valuable and non-substitutable resources and capabilities, into a multidisciplinary integration of both the institution based view (IBV) approach and the role of the contemporary state in providing resources and capabilities to firms. The central problematic this research is seeking to explore is the new resource-based approach of the Indian state. The state is seeking the acquisition of energy assets overseas, using institutional support mechanisms and the deployment of specific state capabilities and resources. Using an in-depth case analysis of the Indian state, this thesis provides evidence of the resource-based approach, in which the state provides a strategic intent for its firms, creates strategic markets for the firms to compete in as well as providing intangible resources. The state is also presented as a source of new intangible resources that provide competitive advantage and insulate firms from competition in specific markets. Insights from elite interviewees representing a cross-section of institutional actors such as academics, ambassadors, senior government officials, policy planners, advises the state, personnel from state-owned and private resource seeking firms as well as from the fourth estate, in the thesis has provided a rich contextual information to evidence resource seeking in the contemporary Indian state. The key contribution of the new conceptual framework, the RBS model has been in integrating a multidisciplinary approach to the traditional resource based view theory of the firm. Using the institutional context of the Indian state, this thesis has provided an appropriate context for the validation of the RBV of the firm.

Submitted by Jean Medeiros (jeanletras@uepb.edu.br) on 2016-02-26T12:24:44Z No. of bitstreams: 2 license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) PDF - Heraldo Antunes Silva Filho.pdf: 31579604 bytes, checksum: 7df08db7246e8704b6c1ca0c63fd2699 (MD5) / Approved for entry into archive by Secta BC (secta.csu.bc@uepb.edu.br) on 2016-03-09T13:25:20Z (GMT) No. of bitstreams: 2 license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) PDF - Heraldo Antunes Silva Filho.pdf: 31579604 bytes, checksum: 7df08db7246e8704b6c1ca0c63fd2699 (MD5) / Made available in DSpace on 2016-03-09T13:25:20Z (GMT). No. of bitstreams: 2 license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) PDF - Heraldo Antunes Silva Filho.pdf: 31579604 bytes, checksum: 7df08db7246e8704b6c1ca0c63fd2699 (MD5) Previous issue date: 2014-12-11 / This research aimed to study the conditions of the biochemical and mechanical properties of biomass of activated sludge systems (SSLM) and define an interface for the application of these properties in the design of projects, based on a model of activated sludge. Thus, the research was divided into two parts: (1) study the conditions of the biochemical and mechanical properties of SSLM and (2) the elaboration and application of activated sludge model. During the first stage we studied the conditions for obtaining measurements of dissolved oxygen and its influencing factors, as well as a study on the respirometry. Still in this stage are two methods of determining the kinetic constants of sedimentation were evaluated. The second stage consisted of 6 experimental operation of activated sludge systems, where each system tied up to a specific treatment goal. With experimental data obtained from activated sludge systems, elaborated a simplified procedure for predicting the cycle time and the optimal treatment volume in each treatment goal. The results showed that the first stage membranes which have less than 5 min -1 K rel lead to impairments of determining the TCO. Results obtained in the first phase also showed that the selection of the respirometric test conditions may exert negative influence when we work under the following conditions: 15 s < λ < 5 s, SSLM concentration of > 5 g L -1 and EC > 1 mS / cm 2 . Focusing on respirometric procedures, that is attested sodium acetate (CH 3 COONa) can be considered as a good representative pattern for the heterotrophic metabolism studies and ammonium bicarbonate (NH 4 HCO 3 ) to study the nitrifying autotrophic metabolism. Is testified also that biomass showing ability to biodesfosfatação difficult in general to determine the constants related to the metabolic properties and that we should therefore give attention to these cases. It was possible to establish that the sodium azide (NaN 3 ) is an excellent inhibitor selective nitration at a concentration of 1 mg L -1 , thus allowing the study of nitrification in two steps. In the second stage, the three studied phases, the third phase was that the systems showed the best performance of removal of constituents within the proposed objectives, and that the sizing procedures were able to predict the operating conditions for RBS systems satisfactorily. / Nesta pesquisa objetivou-se estudar as condições de determinação das propriedades bioquímicas e mecânicas dos sólidos suspensos do liquor misto (SSLM) e definir uma relação para aplicação dessas propriedades nos projetos de dimensionamento, tendo como base um modelo de lodo ativado. Dessa forma, a pesquisa dividiu-se em duas partes: (1) estudo das condições de determinação das propriedades bioquímicas e mecânicas dos SSLM e (2) elaboração do modelo de lodo ativado e aplicação. Durante a primeira etapa foi possível estudar as condições de obtenção das medidas de oxigênio dissolvido e seus fatores intervenientes, bem como desenvolveu-se um estudo sobre a respirometria. Ainda nessa etapa foram avaliados dois métodos de determinação das constantes cinéticas de sedimentabilidade. A segunda etapa foi constituída da operação de 6 sistemas experimentais de lodo ativado (5 em regime de bateladas sequenciais e 1 em regime contínuo), em que cada sistema atrelava-se à um objetivo específico de tratamento. Com os dados experimentais obtidos dos sistemas de lodo ativado, elaborou-se um procedimento simplificado para predição dos tempos de ciclo e do volume de tratamento ideal em cada objetivo de tratamento. Os resultados da primeira etapa mostraram que membranas que apresentem constante de relaxamento (K rel ) inferiores a 5 min conduzem a comprometimentos da determinação da TCO. Resultados também obtidos na primeira etapa mostraram que a seleção das condições do teste respirométrico podem exercer influência negativa quando trabalhamos nas seguintes condições: frequência da coleta de dados de OD entre 15 s < λ < 5 s, concentração de SSLM > 5 g.L -1 e CE > 1 mS/cm 2 . Especificamente sobre os procedimentos respirométricos, atestou-se que o acetato de sódio (CH 3 COONa) pode ser considerado como um bom representante padrão para estudos do metabolismo heterotrófico e que o bicarbonato de amônia (NH 4 HCO 3 ) para o estudo do metabolismo autotrófico nitrificante. Atestou-se também que biomassas que apresentem capacidade de realizar a biodesfosfatação dificultam a determinação das constantes relacionadas com as propriedades metabólicas e que, portanto, devemos dar atenção a esses casos. Foi possível definir que a azida de sódio (NaN 3 ) é um excelente inibidor seletivo da nitratação na concentração de 1 mg.L -1 -1 , permitindo assim o estudo da nitrificação em duas etapas. Na segunda etapa, das 3 fases operacionais estudadas, a terceira fase foi a que os sistemas apresentaram os melhores desempenhos de remoção dos constituintes, dentro dos objetivos propostos, e que os procedimentos de dimensionamento foram capazes de predizer as condições operacionais para sistemas RBS de forma satisfatória.

Made available in DSpace on 2017-05-12T14:46:55Z (GMT). No. of bitstreams: 1 Dilcemara Cristina Zenatti.pdf: 3283328 bytes, checksum: 7aa4b120d287db79b605fc5010d7c5e6 (MD5) Previous issue date: 2007-01-25 / Universidade Federal do Paraná. Campus de Palotina / The agribusiness possesses a high potential of negative environmental impacts related to the generation of residues, overcoat of liquid effluents rich in organic matter and nutrients. The release of those no treated effluents has been the cause of serious damages to the environment. The biological treatment of the nitrogen compositions has been an alternative to improve the quality of the effluents. One of the biological processes is constituted of the nitrification follow by desnitrification, being the nitrification the limiting factor for good performance of the system. The objective of this work was to evaluate the influence of the aeration and of the time of reaction in the process of nitrification of the tilapia effluent in sequential batch reactor with immobilized biomass. The experiment was driven in laboratory scale where two levels of flow of air were tested (QAr = 3 and 6 L.min-1) and two levels of time of reaction (TR = 6 and 12 hours), configuring a factorial experimental planned with four treatments: T1 (QAr=3 L.min-1 and TR = 6:00); T2 (QAr=6 L.min-1 and TR = 6:00), T3 (QAr=3 L.min- 1 and TR = 12:00) and T1 (QAr=6 L.min-1 and TR = 12:00), and four repetitions. The efficiency of Conversion was evaluated (%) of the amoniacal nitrogen to nitrate, the efficiency of Removal (%) of amoniacal nitrogen and the kinetic profile of the nitrification, with the calculation of the apparent kinetic constants k1 and k2. The results showed that the increase in the reaction time (TR) and the increment in the air flow is favorable in the nitrification process. Being that the T4 treatment was what presented better resulted in all the factors analyzed with average values of efficiency for conversion and removal of 57,27± 27,05% and 81,90±3,80, respectively and 0,00300±0,00030 min-1 and 0,00298±0,00024 min-1 for the apparent constants k1 and k2. / A agroindústria possui um elevado potencial de impactos ambientais negativos relacionados à geração de resíduos, sobretudo de efluentes líquidos ricos em matéria orgânica e nutrientes. O tratamento biológico dos compostos nitrogenados tem sido uma alternativa para melhorar a qualidade dos efluentes. Um dos processos biológicos constitui-se da nitrificação seguida da desnitrificação, sendo a nitrificação fator limitante para o bom desempenho do sistema. O objetivo deste trabalho foi avaliar a influência da aeração e do tempo de reação no processo de nitrificação de efluente de abatedouro de tilápia em reator em batelada seqüencial com biomassa imobilizada. O experimento foi conduzido em escala de laboratório onde foram testados dois níveis de vazão de ar (QAr = 3 e 6 L.min-1) e dois níveis de tempo de reação (TR = 6 e 12 horas), configurando um planejamento experimental fatorial com quatro tratamentos: T1 (QAr=3 L.min-1 e TR= 6h); T2 (QAr=6 L.min-1 e TR= 6h), T3 (QAr=3 L.min-1 e TR= 12h) e T1 (QAr=6 L.min-1 e TR= 12h), e quatro repetições para cada tratamento. Avaliou-se a eficiência de Conversão(%) do nitrogênio amoniacal a nitrato, a eficiência de Remoção(%) de nitrogênio amoniacal e o perfil cinético da nitrificação, com o cálculo das constantes cinéticas aparentes k1 e k2. Os resultados mostraram que o aumento no tempo de reação (TR) e o incremento na vazão de ar foram favoráveis no processo de nitrificação, sendo que o tratamento T4 foi o que apresentou melhores resultados em todos os fatores analisados com valores médios de eficiência para conversão e remoção de 57,27 ± 27,05% e 81,90 ± 3,80, respectivamente e 0,00300 ± 0,00030 min-1 e 0,00298 ± 0,00024 min-1 para as constantes aparentes k1 e k2.