Submitted by MARCIA ROVADOSCHI (marciar@unifra.br) on 2018-08-16T17:25:35Z No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Dissertacao_ClaudirGabrielKaufmannJunior.pdf: 4418925 bytes, checksum: 687c661d424523cd9edfde7f671305ad (MD5) / Made available in DSpace on 2018-08-16T17:25:35Z (GMT). No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Dissertacao_ClaudirGabrielKaufmannJunior.pdf: 4418925 bytes, checksum: 687c661d424523cd9edfde7f671305ad (MD5) Previous issue date: 2012-06-05 / The nanotechnology has been focused of many studies and become scientifically and technologically revolutionary. It can be found in many products on the market. The nanoscale is defined as a billionth of a meter (10-9m). The manipulation in this scale has provided a series of studies in the health, computing, physics, chemistry, materials and others fields. In the context of manipulation of nanostructures, this paper proposes an alternative produtcion of NTC on arc discharge method, which dispense the use of sealed cameras and working with water as an insulator environment. The project was divided in two main stages: the software development and the production of NTC. A control system via software to manage the approach speed of the electrode (cathode) and the speed of rotation of electrode (anode) was developed in the first stage. In the second stage, tests were performed with different parameters for the production of NTC: source type (direct current and alternating current), type of catalyst, solubilized iron in the water and iron doped in the anode electrode, and also two types of graphite called A and B (higher purity). The material produced was characterized by the Raman Spectroscopy and Scanning Electron Microscopy techniques. Carbon nanotubes were produced when the graphite with higher purity was used, independently of the type of catalyst and the source used. In addition to the CNT was possible to observe with graphite B the production of several carbon nanostructures as nanosphere, nanorods, nanohoneycombs and nanoflowers of grapheme. However the graphite A (low purity) produced microspheres and nanospheres. / A nanotecnologia vem sendo o foco de diversas pesquisas tornado-se uma verdadeira revolução na ciência e tecnologia, já se pode encontrá-la em diversos produtos no mercado. A nanoescala é definida como a bilionésima parte do metro (10-9m). A manipulação nesta ordem de grandeza despertou uma serie de estudos nas áreas de saúde, computação, física, química, materiais, entre outras. Dentro do contexto de manipulação de nanoestruturas o presente trabalho propõe um método alternativo de produção de nanotubos de carbono por arco elétrico, o qual dispensa a utilização de câmeras seladas, trabalhando com água como meio isolante. O Trabalho foi divido em duas etapas principais: o desenvolvimento do software e a produção de NTC. Na primeira etapa foi desenvolvido um sistema de controle via software para gerenciar a velocidade de aproximação do eletrodo (cátodo) e a velocidade de giro do eletrodo (ânodo). Na segunda etapa realizaram-se testes com diferentes parâmetros para produção de NTC: tipo de fonte (corrente continua e alternada), tipo de catalisador: ferro solubilizado em água e ferro dopado no eletrodo ânodo, além de dois tipos de grafite, denominadas A e B (grafite B com maior pureza). O material produzido foi caracterizado pelas técnicas de Espectroscopia Raman e por Microscopia Eletrônica de Varredura. Nanotubos de carbono foram produzidos quando se utilizou grafite B de alta pureza, independendo do tipo de catalisador e da fonte utilizada. Alem dos NTC foi possível observar com a grafite B a produção de diversas nanoestruturas de carbono como nanoesferas, nanorods (nanovaras), nanofavos de mel e nanoflores de grafeno. Já para a grafite A, com baixa pureza, produziu apenas microesferas e nanoesferas.

Apresentamos um estudo sobre o fenômeno da decoerência durante a evolução temporal de um estado atômico ao interagir com o campo eletromagnético de uma cavidade não ideal. Apresentamos um modelo em que o campo da cavidade esta acoplado a um banho externo e mostramos os efeitos dissipativos que este acoplamento pode gerar na decoerência para um sistema átomo campo. Discutimos as grandezas relevantes para analise da decoerência através de modelos analíticos e numéricos, principalmente entre os acoplamentos átomo campo e campo banho. Sugerimos que o retardamento observado no processo de decoerência seja uma característica geral em sistemas analisáveis como constituídos de três subsistemas acoplados sequencialmente, com propriedades espectrais e acoplamentos suficientemente assimétricos. / We present a study of the phenomenon of decoherence in the time evolution of an atomic state with the electromagnetic field of a non-ideal cavity. We present a model where the cavity field is coupled to an external bath and show the dissipative effects this coupling can generate in the decoherence of the atom field system. We discuss the relevant variables for the analysis of decoherence in terms of analytic and numerical models, especially the atom-field and field-bath couplings. We suggest that the observed hindrance of the decoherence process may be a general property in systems which can be considered as formed by three subsystems coupled sequentially, with spectral properties and sufficiently asymmetric coupling.

O objetivo principal deste trabalho é aplicar complexos de cobre(II), níquel(II), zinco(II) e nióbio(V) como fontes de metais em banhos de eletrodeposição. Os íons metálicos foram coordenados aos ligantes íon oxalato, íon citrato, etilenodiamina (EDA) ou tetraetilenopentamina (TEPA), os quais são aditivos orgânicos típicos em banhos de eletrodeposição. Os complexos foram caracterizados por análise elementar, espectroscopias nas regiões do infravermelho e ultravioleta-visível e voltametria cíclica. Foram realizadas eletrólises em presença de dois complexos de coordenação em ausência de quantias adicionais de aditivos, usando aço 1010 como substrato a pH = 4.5 (H2SO4/Na2SO4), resultando em depósitos com dois elementos metálicos. Os depósitos apresentaram aspectos morfológicos com boas qualidades e sem falhas. Em adição, os depósitos foram analisados por EDX, reflectância difusa e espectroscopia de raio-X e também foram realizadas medidas de curvas de polarização. Os depósitos obtidos a partir dos complexos gerados ex-situ mostraram morfologias melhores do que depósitos obtidos de soluções preparadas com os sais dos metais na presença dos aditivos, mediante as mesmas condições de trabalho. É sugerido que os metais de partida, coordenados a aditivos influenciam o processo de eletrodeposição, propiciando depósitos com potenciais de corrosão deslocados por até +200 mV em 0.5 mol.L-1 NaCl (1 mV.s-1). / The main goal of this work is to use copper(II), nickel(II), zinc(II) and niobium(V) complexes as metal plating source in electrodeposition baths. The metal ions were coordinated with oxalate, citrate, ethylenediamine (EDA) or tetraethylenepentamine (TEPA) as ligands, which are typical organic additives in electroplating. The complexes were characterized by elemental analysis, infrared and ultraviolet spectroscopies and cyclic voltammetry. The electrolyses in presence of two coordination complexes in the baths were carried out in absence of extra amount of additive, using 1010 steel as substrate at pH = 4.5 (H2SO4/Na2SO4). Deposits with two metal elements from the ex-situ generated complexes showed good quality morphologic aspect without crashes. Further, the deposits were analyzed by EDX, diffuse reflectance and X-ray spectroscopy and polarization curves were recorded. The deposits showed better morphologies than deposits obtained from the metal salt solutions in presence of additives under similar conditions. It is suggestive that the starting metal plating coordinated with additives influences the electrodeposition processes, affording deposits with corrosion potentials shifted over +200 mV in 0.5 mol.L-1 NaCl (1 mV.s-1).

Neste trabalho, é apresentado um estudo sobre a influência de aditivos em banhos de eletrodeposição de Au, análise da morfologia dos depósitos de Au e o crescimento de multicamadas da liga AuxSny por deposição eletroquímica. Os banhos de eletrodeposição estudados são baseados em uma composição, comum na literatura, formada por tetraclorourato(III) de potássio (KAuCl4), cloreto de estanho(II) (SnCl2), sulfito de sódio (Na2SO3), e citrato de amônio [(NH4)HC6H5O7]. Os contatos de solda da liga AuxSny, aplicáveis em diversos dispositivos microeletrônicos, podem ser formadas de maneira mais econômica a partir de banhos eletroquímicos. Banhos ácidos e reagentes de baixa toxicidade são exigências comuns dos novos banhos de eletrodeposição. A formação de multicamadas permite, ainda, ampliar o uso do metal de solda em dispositivos sensíveis a altas temperaturas, devido ao baixo ponto de fusão da liga. A obtenção das ligas AuxSny utilizando deposição eletroquímica, foi feita com base no estudo sobre banho de eletrodeposição e seus depósitos, a partir de um banho para deposição da liga AuxSny já conhecido. O aprimoramento do banho de eletrodeposição foi focado no banho de eletrodeposição de Au, com três opções de aditivos, buscando avaliar as características dos depósitos e o tempo de estabilidade do banho. Os aditivos utilizados foram hipofosfito de sódio (NaH2PO2), metanal (HCHO) e tiossulfato de sódio (Na2S2O3), separadamente. Esses banhos foram analisados por voltametria cíclica, e os depósitos obtidos a partir de eletrodeposições foram caracterizados por Espectrometria por Retroespalhamento de Rutherford (RBS), Microscopia Eletrônica de Varredura (SEM) e, em alguns casos, por Espectrometria de Energia Dispersiva de Raios X (EDS). Análises de dimensão fractal e de escalamento dinâmico da rugosidade forneceram detalhes importantes sobre a morfologia superficial dos depósitos. .A adição de Na2S2O3 ao banho permitiu o desenvolvimento de um novo banho de eletrodeposição para a co-deposição de Au AuxSny. O Na2S2O3 atua como um complexante dos íons de Au(I) juntamente com o sulfito de sódio. O emprego de 3 g L-1 de Na2S2O3 evita a degradação do banho durante as eletrodeposições. Finalmente, o estudo da eletrodeposição de multicamadas foi feito por controle do potencial aplicado e por controle da corrente aplicada. As multicamadas obtidas apresentaram camadas da liga AuxSny com a concentração de Sn incorporado, variando entre 6 % e 49 % (em porcentagem atômica). / It is shown in this work a study about the influence of additives in baths for electrodeposition of Au, analysis of morphology of gold deposits and the growth of multilayered AuxSny alloys from improved electrodeposition baths based on a common composition of the literature containing potassium gold(III) chloride (KAuCl4), tin(II) chloride (SnCl2), sodium sulfite (Na2SO3) and ammonium citrate dibasic [(NH4)HC6H5O7]. The AuxSny solders are commonly used in microelectronic devices. These solders can be applied in a number of ways, and electrochemical deposition is an attractive alternative due to the low cost process. Acidic baths and low toxicity reagents are common requirements of new electrochemical baths. The multilayered AuxSny alloys are applicable to temperature sensitive materials due to its reduced melting point temperature. Therefore, the study of electrodeposition of AuxSny alloys began with an already known bath and aiming its improvement. The focus of interest was the gold bath, which received additives to improve control of the deposits and their stability. The additives used were sodium hypophosphite (NaH2PO2), methanal (HCHO) and sodium thiosulfate (Na2S2O3), one of each time. These baths were analyzed by cyclic voltammetry and the deposits obtained from these baths were analyzed by Rutherford Backscattering Spectrometry (RBS), Scanning Electron Microscopy (SEM) and, in some cases, Energy Dispersive Spectrometry (EDS). Fractal dimension and dynamic scaling of the surface width analysis allowed one to quantify the surface morphology details. The addition of Na2S2O3 to the bath allowed the development of a new electrodeposition bath for co-deposition of AuxSny. The Na2S2O3 acts as complexing agent of Au(I) ions together with sodium sulfite. The use of 3 g L-1 of Na2S2O3 avoids bath degradation during the electrodepositions. Potential-controlled and current-controlled electrodepositions were employed to obtain multilayers of AuxSny alloys. The multilayer deposits obtained presented between 6 atomic % and 49 atomic % of tin.

>Magister Scientiae - MSc / Aquaculture is a vast industry all over the world and has increased significantly during the past 30 years. In South Africa, finfish aquaculture farms stretch from Gansbaai to as far as Richards bay with the potential of extending into Mozambique. The future success of this fast growing industry in South Africa strongly relies on the development of the supporting sector such as government legislation, sponsorship, participation of the pharmaceutical industry and research and development in aquatic organism health management. Diplectanum oliveri Williams, 1989, a monogenean gill parasite of both Argyrosomus japonicus (Temminck & Schlegel, 1843) (dusky kob) and A. inodorus Griffiths & Heemstra, 1995 (silver kob) is currently regarded in South Africa as the most persistent ectoparasite associated with the culture of both fish species, causing pathological tissue changes in the areas associated with attachment and feeding which can result in stock losses. The egg production of D. oliveri was used to evaluate and develop a method to quantify monogenean infections on fish, by counting the eggs produced by infra-populations of these parasites over a 24-hour period and to determine the reliability of this method as a non-invasive/non-destructive method to quantify the intensity of an individual infra-population of parasites on a single host. Currently, Diplectanum spp. on dusky kob are being controlled in local mariculture facilities using methods and drugs that are traditionally used for monogeneans (flukes) and are regarded as effective. Most of these drugs are, however, no longer approved for use in food fish and none of them has proven to be very effective in controlling D. oliveri in culture facilities, which can result in subsequent re-infections of epidemic proportion. Currently, there are no anthelmintics registered for aquaculture in South Africa. An registered anthelmintic used in terrestrial animals (sheep, goats, cattle and ostriches) containing praziquantel was tested at various concentrations and exposures against D. oliveri on A. japonicus to determine the efficacy of two different formulations and the potential for "off label" use. The 20 ppm (high) praziquantel concentration treatments eliminated all adult parasites, but caused significant measureable stress and affected the central nervous system of the fish, which resulted in death of all fish in the solution group after 18 hours. The 2 ppm (low) concentrations failed to remove all adult parasites. Although both the 2 hour (short) exposure/high concentration and 24 hour (long) exposure/low concentration of the suspension formulation were effective, but only the short exposure/high concentration eliminated all adult parasites with little change in behaviour by the treated fish.

Since year 2005 all Nordic companies on a regulated stock market needs to present their accounts according to the IFRS-standards by IASB. This has affected the management of goodwill that now needs to be exposed for an impairment test every year.  This paper handles the impairment of goodwill in Nordic companies to test their ability to follow IAS 36 in the IFRS-standards and neutrality in The Conceptual Framework for Financial Reporting. Goodwill was earlier exposed to linear depreciation according to the national rules, while nowadays it needs to be impaired every time it’s warranted according to the calculated future cash flow. This creates an opportunity for companies to affect the accounts, an opportunity that can be explained by the Agent theory and Big Bath. How companies handle this change in accounting is tested to see if there is any relationship between goodwill impairments and future cash flow. Earlier studies have been made on the American market by Jarva (2009) and his model to calculate future cash flow is used in this paper.

Income decreasing strategies conducted by management could be harmful for various stakeholders. One example is big bath accounting, which could be accomplished in numer- ous ways. This study focus on big baths achieved by recognising impairments of goodwill. Purpose - The purpose of this study is to examine patterns of association between big bath accounting and impairment of goodwill within the telecommunication service industry in Europe. Further, this study aim at contributing to the discussion regarding utilisation of big baths through impairments of goodwill, and takes the perspective of an external stakehold- er. Delimitations - The study is restricted to European telecommunication entities comprised in STOXX Europe 600 Index. Method - This study was conducted using a hybrid of qualitative and quantitative research strategy with a deductive approach. The five indicators used to identify various big bath behaviours were inspired and derived from theory and previous research. Data from 2009 to 2015 was collected from the companies’ annual reports and websites, and analysed by the help of codification of each fulfilled indicator where 2009 merely served as a compara- tive year for 2010. By the use of a scoreboard the collected data was summarised on an ag- gregated yearly basis as the industry, not the specific companies, were analysed. Empirical findings - The results of this study suggests that big baths are executed among tele- communication companies within Europe. These are conducted simultaneously as impair- ments of goodwill are present, facilitated by earning management. A possible explanation is considered to be the room for interpretation inherent in IAS 36, enabling goodwill impair- ments to be recognised on managers’ command. Thereby an impairment could be “saved” for better or worse circumstances, or recognised when there exist an opportunity to max- imise (the manager's) wealth in the future. This study reveal the co-occurrence of goodwill impairments and big bath-indications, however a review of causal relationships are not en- abled by the limitations of the chosen method.

This dissertation aims at addressing two important theoretical questions which are still debated in the statistical mechanical community. The first question has to do with the outstanding problem of how to reconcile time-reversal asymmetric macroscopic laws with the time-reversal symmetric laws of microscopic dynamics. This problem is addressed by developing a novel mechanical approach inspired by the work of Helmholtz on monocyclic systems and the Heat Theorem, i.e., the Helmholtz Theorem. By following a line of investigation initiated by Boltzmann, a Generalized Helmholtz Theorem is stated and proved. This theorem provides us with a good microscopic analogue of thermodynamic entropy. This is the volume entropy, namely the logarithm of the volume of phase space enclosed by the constant energy hyper-surface. By using quantum mechanics only, it is shown that such entropy can only increase. This can be seen as a novel rigorous proof of the Second Law of Thermodynamics that sheds new light onto the arrow of time problem. The volume entropy behaves in a thermodynamic-like way independent of the number of degrees of freedom of the system, indicating that a whole thermodynamic-like world exists at the microscopic level. It is also shown that breaking of ergodicity leads to microcanonical phase transitions associated with nonanalyticities of volume entropy. The second part of the dissertation deals with the problem of the foundations of generalized ensembles in statistical mechanics. The starting point is Boltzmann's work on statistical ensembles and its relation with the Heat Theorem. We first focus on the nonextensive thermostatistics of Tsallis and the associated deformed exponential ensembles. These ensembles are analyzed in detail and proved (a) to comply with the requirements posed by the Heat Theorem, and (b) to interpolate between canonical and microcanonical ensembles. Further they are showed to describe finite systems in contact with finite heat baths. Their mechanical and information-theoretic foundation, are highlighted. Finally, a wide class of generalized ensembles is introduced, all of which reproduce the Heat Theorem. This class, named the class of dual orthodes, contains microcanonical, canonical, Tsallis and Gaussian ensembles as special cases.

Ce travail s'inscrit dans le cadre de la recherche d'une amélioration des conditions de réalisation des dispositifs photovoltaïques à base du matériau semiconducteur ternaire CuInS2, qui doit constituer la couche absorbante dans la cellule solaire. Différentes techniques économiquement rentables ont été retenues pour l'élaboration de ce matériau : nous avons sélectionné le dépôt chimique en solution (CBD), la pulvérisation chimique réactive avec air (spray) et la pulvérisation chimique réactive sans air (PSA). Les matériaux élaborés ont été inclus dans des dispositifs photovoltaïques, pour lesquels le CuInS2 est réalisé soit avec la méthode PSA (CuInS2/ZnO/SnO2/verre ou CuInS2/In2S3/ZnO/SnO2/verre), soit avec la méthode de spray (CuInS2/In2S3:Al/SnO2/pyrex ou CuInS2/ZnS:In/SnO2/pyrex).Globalement, les propriétés structurales, morphologiques et optiques sont satisfaisantes. Pour les cellules incluant le CuInS2 déposé par spray, le photo-courant existe et atteint jusqu'à 200 µA dans le cas de la cellule CuInS2/ZnS:In/SnO2/pyrex, ou environ 4 A/cm2. / Photovoltaic solar cells based on I–III–VI2 ternary chalcopyrite absorber layers, have been the focus of intense investigation for over two decades. The use of chalcopyrite absorbers are highly appealing since their bandgaps correlate well to the maximum photon power density in the solar spectrum. Cu-chalcopyrite semiconductors have been studied extensively in recent years due to their applications as absorbers for large-area low-cost photovoltaic devices. CuInS2 as a chalcopyrite-semiconductor material has a direct band gap of 1.5 eV, a high absorption coefficient and nontoxic constituents and is, therefore, a promising candidate for photovoltaic applications. Different methods have been used to prepare CuInS2 films. Among these methods, spray pyrolysis, used in the present study, is an attractive one because large-area films with good uniformity may be prepared at low cost.

京都大学 / 新制・論文博士 / 博士(理学) / 乙第13434号 / 論理博第1576号 / 新制||理||1682(附属図書館) / 京都大学大学院理学研究科 / (主査)教授 谷村 吉隆, 教授 林 重彦, 教授 渡邊 一也 / 学位規則第4条第2項該当 / Doctor of Science / Kyoto University / DGAM