The euphonium has been an integral part of wind bands and brass bands for more than a century. During this time the instrument has grown in stature in both types of band, as an ensemble member and a solo instrument. Until recently, however, the instrument has been underrepresented in orchestral literature, although a growing number of composers are beginning to appreciate the characteristics of the instrument. The purpose of this research is to explore the perceived rise of the euphonium in an orchestral environment through analyzing the significance of the role it plays within Lorin Maazel's Music for Flute with Tenor Tuba Obbligato (1995) and Karl Jenkins' Cantata Memoria (2005); specifically, how the euphonium contributes to the orchestral scores in relation to its capabilities as an instrumental voice.

A corrosão é um fenômeno de interface que deteriora um metal através de reações químicas ou eletroquímicas, sendo caracterizada como um processo espontâneo, onde os materiais são transformados do estado metálico para uma forma combinada, decorrente da interação dos compostos metálicos com as substâncias do meio que estão inseridos. Como os prejuízos oriundos de processos corrosivos são elevados (estimativas mostram que os valores variam em torno de 3% a 4% do PIB de uma nação), estudos que minimizem estes processos são de vital importância econômica. Nos últimos anos, diversas pesquisas foram realizadas com o intuito de estudar superfícies hidrofóbicas e super-hidrofóbicas devido à sua função de autolimpeza, baixa aderência de contaminantes e proteção contra os efeitos corrosivos. Estudos recentes propõem a utilização de ácidos carboxílicos como percussores à formação destas camadas protetoras, sendo que melhores resultados foram obtidos utilizando ácidos carboxílicos de cadeias longas (acima de 11 carbonos). O ácido n-tetradecanóico (CH3(CH2)12COOH) pode ser utilizado sobre cobre e, após 10 dias de imersão em solução alcoólica de 0,06 mol/L, uma película super-hidrofóbica é formada sob o substrato, porém as características superficiais do metal são afetadas e uma camada esverdeada de carboxilato de cobre é formada. O presente trabalho, além de comprovar o efeito protetor desta camada superhidrofóbica formada, propôs a utilização do ácido n-tetradecanóico em um tratamento superficial, de forma a atuar como uma película protetora contra processos corrosivos, considerando curtos períodos de imersão em solução de ácido mirístico de forma a preservar as características superficiais do metal utilizado e torná-lo comercialmente e esteticamente mais atrativo. Os metais avaliados foram: cobre, latão e aço carbono. As técnicas eletroquímicas empregadas para a avaliação da película formada foram: curva de polarização, resistência de polarização linear (Rp) e espectroscopia de impedância eletroquímica (EIE). Medidas de ângulo de contato foram realizadas a fim de comprovar a viii hidrofobicidade do filme formado e espectroscopia de infravermelho e Raman, além da difratometria de raios X, a fim de caracterizar sua composição química. Melhores resultados foram obtidos para cobre, onde os ensaios comprovaram um aumento da hidrofobicidade da superfície metálica à medida que se aumentava o tempo de imersão dos corpos-de-prova em solução alcoólica 0,06 mol/L de ácido ntetradecanóico, atingindo valores de 116,1o e 149,8o após, respectivamente, 12 horas e 5 dias de imersão. Além disso, através de medidas de espectroscopia de impedância eletroquímica, também foi avaliado o grau de proteção da película hidrofóbica formada com relação ao substrato puro, sendo observado um aumento na proteção da superfície após 12 horas de imersão. / Corrosion is an interface phenomenon that deteriorates a metal by chemical or electrochemical reactions. It is characterized as a spontaneous process, where materials are transformed from the metallic state to a combined form. As corrosive processes damages are high (estimates show that the values vary around 3% to 4% of a nation GDP), studies that minimize corrosion reactions are of vital economic importance. Recently, several studies were performed in order to study hydrophobic and superhydrophobic layers due to its self-cleaning function, low adherence of contaminants and protection against corrosive effects. Recent studies propose the use of carboxylic acids as precursors to the formation of such protective layers, with best results being obtained using long chain carboxylic acids (up to 11 carbons). Over copper, the usage of n-tetradecanoic acid (CH3(CH2)12COOH) has showed good results after 10 days immersion in 0.06 mol/L ethanolic solution. Experimental results proved that the super hydrophobic surface could improve significantly the corrosion resistance of copper, although the surfaces have been strongly modified and a green oxidation layer (which is a copper carboxylate) has been formed over the etched copper surface. Besides proving the protective effect of the super-hydrophobic layer formed, this work also studied the use of n-tetradecanoic acid as a temporary protective layer, considering short immersion periods. In this way, the metal surface characteristics were preserved. The metals studied were: copper, brass and carbon steel. The electrochemical techniques employed for evaluation of the formed film were: polarization curves, linear polarization resistance (Rp) and electrochemical impedance spectroscopy (EIS). Contact angle measurements were performed to prove the hydrophobicity of the film and X-ray diffraction, Raman and Infrared spectroscopy were also utilized to characterize its composition. x Test samples of these metals were immersed, at ambient temperature, in 0.06 mol/L of n-tetradecanoic ethanolic solution, for different immersion periods, in order to monitor the formation of the protective layer and its hydrophobicity. Furthermore, in order to study the formation and persistence of the formed film, electrochemical tests were also performed in 3.5 wt. % NaCl solution. The results obtained for copper demonstrate an increase of the metal surface hydrophobicity for longer immersion time in 0.06 mol/L n-tetradecanoic acid solution, reaching values of 116.1o and 149.8o after, respectively, 12 hours and 5 days of immersion. Furthermore, the degree of protection of hydrophobic film was also evaluated by electrochemical impedance spectroscopy measurements and the best results were obtained for 12hs of immersion.

This essay is an analysis of the objects made of bronze found in an excavation Västergarn parish, Gotland, in 2010, conducted by the University of Gotland. The studied material presented in this essay comes from contexts inside, as well as nearby the foundation of a medieval building which purpose is still not certain. The first purpose of this study is to present the bronze-objects found inside and nearby the foundation of house 6, and to see if there are any datable objects. There is also a discussion whether there has been any bronze-crafting in the area. The second purpose is to make a contextual analysis to see if there are any differences between the material found outside and inside of the building, and what conclusions can be made regarding the function and use of the building. A spatial analysis has also been made to distinguish any patterns of the distribution of material inside and around the house.The result of this essay is partly a presentation of the material, but also that there has occurred some bronze-crafting in the form of cutting metal sheets inside or near the foundation treated in this essay. There is no evidence for casting bronze near the house foundation.The frequency of finds from outside the foundation compared to the frequency of finds within the foundation is nearly quadruple, which is to be expected since there probably has been a wooden floor inside the house to prevent all but the tiniest objects from falling through. Objects that landed on the floor were cleaned out, just to land near the entrance of the building. The finds from within the building much resembles the finds from outside the building, and the distribution-patterns of the trench indicates that the entrance to the building probably was located near the north-west corner or near the south-east corner.Hopefully, this study contributes another piece to the great puzzle that is Västergarn.

Not available / text

The effect of deformation on microstructural changes in metals and alloys is the subject of considerable practical interest. The ultimate goal is to control, improve and optimize the microstructure and texture of the finished products produced by metal forming operations. The development in the subject field is remarkable but a more in-depth study could lead us to the better understanding of the phenomena.   In the present work microstructural evolution during the plastic deformation of as-cast pure metals and alloys is studied. An experimental method was developed to study the material behavior under the hot compression testing. This method was applied on the as-cast structure of copper, bearing steel, Incoloy 825 and β brass at different temperatures and strain rates. The temperature of the samples was measured during and after the deformation process. The microstructure of the samples was examined by optical microscopy and scanning electron microscopy (SEM). The microstructural evolution during deformation process was investigated by transmission electron microscopy (TEM) and electron backscatter diffraction (EBSD). The samples were subsequently subjected to electron microprobe analysis (EMPA) to investigate the effect of the deformation on the microsegregation of Mo, Cr, Si, and Mn.   It was observed that the temperature of the samples deformed at strain rates of 5 and 10 s-1 increases abruptly after the deformation stops. However, compression test at the lower strain rates of 1 and 0.5 s-1 revealed that a constant temperature was maintained in the early stage of deformation, followed by an increase until the maximum temperature was obtained. This temperature behavior can be explained by the microstructural evolution during the deformation process. Micrograph analysis revealed the formation of deformation bands (DBs) in highly strained regions. The DBs are highly effective sites for recrystallization. The interdendritic regions are suitable sites for the formation of DBs due to the high internal energy in these regions. EMPA indicated a tendency towards uphill diffusion of Mo in the DBs with increasing strain. The effect of strain on the dissolution of carbides in the band structure of bearing steel was investigated by measuring the volume fraction of carbides inside the band structure at different strain levels. The results indicate that carbide dissolution is influenced by strain.    The microstructural evolution inside the DBs was studied as a function of several properties: temperature, internal energy, and microsegregation. Compression of β brass revealed that twinning is the most prominent feature in the microstructure. EBSD analysis and energy calculations demonstrated that the twinning is not due to a martensitic process but rather the order/disorder transition during the deformation process. The effect of heat treatment at Tc (650°C) prior to deformation on the microstructure of β brass was also investigated, which revealed a relationship between twin formation and the anti-phase domain boundaries / <p>QC 20131104</p>

With the advancement and accessibility of local probing techniques that can operate at the submicron scale it has become possible to analyse the local corrosion properties of industrially important metallic materials and relate these properties to microstructure characteristics of the same materials. In this doctoral study the focus has been on copper-zinc samples, both as industrial brass alloys and as micro-patterned copper-zinc samples. They have been exposed to dilute chloride solutions and to an atmosphere that mimics indoor conditions that cause corrosion. The main goal has been to investigate micro-galvanic effects caused by surface heterogeneities in the copper-zinc samples, and the corrosion inhibition ability of a self-assembled octadecanethiol (ODT, CH3(CH2)17SH) monolayer when applied to these heterogeneous samples. The local chemistry, local electrochemistry, and local surface chemistry in the presence of the copper-zinc galvanic couplings have been elucidated, and their importance has been investigated for corrosion initiation, propagation, termination, and inhibition. A broad spectrum of local probe techniques has been utilised. They include optical microscopy (ex situ and in situ), electrochemical techniques, scanning electron microscopy with energy dispersive spectroscopy, atomic force microscopy, scanning Kelvin probe force microscopy and confocal Raman spectroscopy. In addition, infrared reflection absorption spectroscopy (in situ) and vibrational sum frequency spectroscopy have been employed to analyse the formation of corrosion products and monitor the corrosion kinetics.    A characteristic selective zinc dissolution process was triggered in non-metallic inclusions when a brass alloy was exposed to 1 mM NaCl. Disc-like corrosion areas spread radially outwards from the inclusions, the shape and termination of which was attributed to accessibility to chloride ions. An ODT-layer deposited on brass retarded access to chloride ions at the brass surface and slowed down the radial corrosion process. Instead a delayed formation of filiform-like corrosion was observed.    Upon exposure of the copper-zinc patterned sample to humidified air containing formic acid, micro-galvanic effects were induced by the copper patches on zinc that accelerated the zinc dissolution in the thin aqueous adlayer with concomitant precipitation of zinc formate. The micro-galvanic effects not only resulted in accelerated corrosion rates for zinc, but also in broadening of shapes and atomic structures for the corrosion products formed. Crystalline zinc oxide and zinc formate were observed on the copper-zinc patterned samples, whereas amorphous zinc oxide and zinc formate were formed on the bare zinc surface. Micro-galvanic effects occurred in the two-phase Cu40Zn (Cu with 40 wt% Zn) brass alloy as well, induced by more zinc-rich beta-phase grains surrounded by an alpha matrix with lower zinc-content.    The application of a self-assembled monolayer of ODT for corrosion inhibition of pure zinc and the patterned copper-zinc samples was also explored. In situ infrared reflection absorption spectroscopy analyses showed that ODT initially reduced the rate of zinc formate formation on pure zinc and on the copper-zinc micro-patterned sample. However, the inhibition efficiency was slightly reduced with exposure time due to local removal of ODT on pure zinc and on the micro-patterned samples. This caused micro-galvanic effects that resulted in increased rates of zinc formate formation on the ODT-covered samples – even higher than on the uncovered samples. When applied to the single-phase Cu20Zn alloy, ODT resulted in a corrosion inhibition that was comparable to that of pure copper, a metal for which ODT has shown very good corrosion inhibition. On double-phase Cu40Zn local galvanic effects resulted in less efficient corrosion inhibition and more abundant corrosion products than on Cu20Zn. Based on vibrational sum frequency spectroscopy, the ODT-layer retained its well-ordered molecular structure throughout the exposure to both Cu20Zn and Cu40Zn.    In all, the inhibiting action of the ODT-layer was attributed to the transport hindrance of corrosion promoters (O2, H2O, and HCOOH) to the brass surface. This result suggests that ODT can function as a temporary corrosion inhibitor for brass exposed to benign indoor environments. / Med utvecklingen av och tillgången till lokala analysmetoder som kan ge information med en lateral upplösning på mindre än en mikrometer har det blivit möjligt att analysera lokala korrosionsegenskaper hos industriellt viktiga metalliska material och relatera dessa egenskaper till mikrostrukturen hos samma material. I doktorsavhandlingen har denna möjlighet utnyttjats för koppar-zinkprover, dels som industriella mässingslegeringar dels som mikro-mönstrade koppar-zinkprover, som exponerats för utspädda kloridlösningar samt för en atmosfär som kan efterlikna den atmosfäriska korrosionen inomhus. Det huvudsakliga målet har varit att undersöka dels mikro-galvaniska korrosionseffekter som orsakas av heterogeniteter på koppar-zinkytorna dels korrosionsförmågan hos självorganiserande monolager av oktadekantiol (ODT, CH3(CH2)17SH) vid adsorption på dessa heterogena ytor. På så vis har den lokala kemin, ytkemin och elektrokemin kunnat klarläggas i närvaro av galvaniska effekter, och dess betydelse har undersökts för korrosionsprocessens initiering, propagering, terminering och inhibering. Ett brett spektrum av lokala analysmetoder har utnyttjats. De innefattar ljusoptisk mikroskopi (ex situ och in situ), elektrokemiska metoder, svepelektronmikroskopi med energidispersiv röntgen-spektroskopi, atomkraftsmikroskopi för mikro-kartering och Voltapotentialmätningar samt konfokal Raman-spektroskopi. Dessutom har infrarödreflektions absorptionsspektroskopi (in situ) och vibrationssummafrekvens spektroskopi (engelska: vibrational sum frequency generation) använts.    När en mässingslegering exponerades för 1 mM NaCl observerades en selektiv utlösning av zink med karakteristiskt utseende som växte radiellt från icke-metalliska inneslutningar för att bilda cirkulärt formade korrosionsområden. Formen och termineringen av denna korrosionsprocess bestäms av tillgången på kloridjoner. När ett monolager av ODT adsorberades på mässingslegeringen hämmades tillgången av kloridjoner på mässingsytan och den radiella korrosionsprocessen stannade upp. Istället iakttogs en fördröjd bildning av s.k. filiform korrosion.    Vid exponering av mikro-mönstrade koppar-zinkprover för befuktad luft med låga tillsatser av myrsyra inducerades mikro-galvaniska effekter i gränsen mellan koppar och zink som accelererade utlösningen av zink i den adsorberade fuktfilmen på provet, under samtidig utfällning av zinkformat. De mikro-galvaniska effekterna resulterade inte bara i förhöjda korrosionshastigheter jämfört med de på ren zink, utan även i andra faser hos bildade korrosionsprodukter. På de mikro-mönstrade koppar-zinkproverna bildades kristallint zinkoxid och zinkformat, under det att amorft zinkoxid och zinkhydroxyformat bildades på ren zink. Mikrogalvaniska effekter observerades även i den tvåfasiga mässingslegeringen Cu40Zn (Cu med 40 vikt-% Zn) orsakade av kontakten mellan den mer zinkrika beta-fasen och den omgivande alfa-fasen med lägre zinkhalt.    Appliceringen av ett självorganiserat monolager av ODT för korrosionsinhibering av ren zink och koppar-zinkprover har också undersöks. In situ infrarödreflektions absorptionsspektroskopi visade att adsorberat ODT initialt hämmade bildningen av zinkformat på ren zink och på de mikro-mönstrade koppar-zinkproverna. Med tiden minskade ODTs korrosionsinhiberings-förmåga på grund av att ODTs vidhäftning lokalt försvann. De mikro-galvaniska effekter som därigenom uppstod resulterade i bildandet av zinkformat som med tiden blev snabbare på de ODT-belagda proverna än på motsvarande prover utan ODT. När ODT applicerades på den enfasiga mässingslegeringen Cu20Zn resulterade detta i en korrosionsinhibering som var jämförbar med den på ren koppar, en metall på vilken ODT tidigare visat mycket bra korrosionsskydd. På den tvåfasiga mässingslegeringen Cu40Zn ledde lokala galvaniska effekter till en mindre effektiv korrosions-inhibering och en rikligare mängd korrosionsprodukter än på Cu20Zn. Baserat på vibrationssummafrekvens spektroskopi behöll ODT-lagret dess välordnade struktur under hela exponeringen på både Cu20Zn och Cu40Zn.    ODTs korrosionsinhibering tillskrivs främst transport-hämningen av korrosionsstimulatorer (O2, H2O och HCOOH) till mässingsytan och antyder att ODT kan fungera som en temporär korrosionsinhibitor för mässing i milda inomhusmiljöer. / <p>QC 20140915</p>

Ziel der Arbeit war das mögliche Einsatzspektrum von Sekundärmaterialien im Prozess der Herstellung von Bauteilen aus Aluminiummehrstoffbronzen (CuAl15Fe5Ni2Mn2) zu erweitern, um das Werkstoffrecycling in der Gießerei auf höchstmöglichem Niveau einzusetzen. Verschiedene Raffinationsmöglichkeiten wurden analysiert und 4 davon getestet. Die Schleifstaubaufbereitung mittels Magnetbandringscheider und Permanent- Magnettrommelscheider wurde erprobt und im industriellen Maßstab getestet. Weiterhin wurde die Gasraffinationswirkung auf die Schmelze mit Stickstoff und Argon sowie mit der Zugabe von Chlor und Ammoniak getestet. Die Salzraffination der Schmelze wurde untersucht und die optimalen Raffinationszusammensetzungen wurden definiert. Die fraktionierte Kristallisation als Raffinationsmethode für die Aluminiummehrstoffbronze wurde ebenfalls untersucht. Im Anschluss wurden die Einsatzmöglichkeiten der Raffinationstechnologien in der Giessereiindustrie kritisch bewertet.

Made available in DSpace on 2016-12-08T17:19:20Z (GMT). No. of bitstreams: 1 pre-texto.pdf: 48629 bytes, checksum: 90cec7d8f232aba11ddcdee4ce04d6d8 (MD5) Previous issue date: 2004-12-09 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / This research investigated the protection against corrosion of C-360 brass samples (Cu-Zn with 6063% Cu) coated with Inconel (Ni0,72, Cr0,15, Fe0,08), TiNx and Cr/Ni films. The Inconel and TiNx films are deposited by sputtering process and the Cr/Ni films are deposited via electrochemical process. The dynamic electrochemical corrosion tests were carried out with NaCl 3%, at a potential sweeping speed of 0,8 mV/s. After the corrosion tests the samples surfaces were analyzed through Scanning Microscopic Electronic (SEM). These types of samples were tested: Samples combining films on brass surfaces: Cr/Ni; Inconel; TiNx/Cr/Ni; TiNx/Inconel. Also tested were samples with different concentrations of nitrogen in the TiNx compound. The results of the electrochemical evaluation show that the depositing of films may offer good protection against corrosion in brass pieces. Small variations in the nitrogen concentration in TiNx films do not significantly alter the resistance to corrosion. The Inconel films deposited by sputtering present more resistance to corrosion than Cr/Ni films deposited electrochemically. This is attributed to better porosity communicating with the substrate present in the Cr/Ni films. When TiNx films are deposited over the samples coated with Cr/Ni films and with Inconel intermediary films of Cr/Ni, a better behavior in relation to the corrosion in the samples coated with intermediary films of Cr/Ni is observed. In this case, the TiNx films overcome the porosity of intermediary films. The highest resistance to corrosion of the samples coated with the TiNx/Cr/Ni combination is attributed to a less roughness on the surface of these samples / Neste trabalho estuda-se a proteção contra a corrosão de amostras de latão C-360 (Cu-Zn com 60-63% Cu) recobertas com filmes de Inconel (Ni0,72Cr0,15Fe0,08), TiNx e Cr/Ni. Os filmes de inconel e TiNx são depositados pelo processo de pulverização catódica (sputtering) e os filmes de Cr/Ni são depositados via processo eletroquímico (comercial). Os ensaios potenciodinâmicos de corrosão eletroquímica são realizados em NaCl 3%, a uma velocidade de varredura do potencial de 0,8 mV/s. Após o ensaio de corrosão as superfícies das amostras foram analisadas via Microscopia Eletrônica de Varredura (MEV) e ótica. Foram testadas amostras com as seguintes combinações de filmes sobre a superfície de latão: Cr/Ni; Inconel; TiNx/Cr/Ni; TiNx/Inconel. Também foram testadas amostras com diferentes concentrações de nitrogênio no composto TiNx. Os resultados da avaliação eletroquímica mostram que a deposição de filmes pode proporcionar boa proteção à corrosão em peças de latão. Observa-se que pequenas variações na concentração de nitrogênio em filmes de TiNx não alteram significativamente a resistência à corrosão. Os filmes de inconel depositados por sputtering apresentam maior resistência à corrosão que filmes de Cr/Ni depositados via eletroquímica. Isso é atribuído à maior porosidade comunicante com o substrato presente nos filmes de Cr/Ni. Quando se depositam filmes de TiNx sobre amostras recobertas com filmes de Cr/Ni e com filmes de inconel, observa-se um melhor comportamento frente à corrosão nas amostras recobertas com filmes intermediários de Cr/Ni. Neste caso, os filmes de TiNx se sobrepõem à porosidade dos filmes intermediários. A maior resistência à corrosão das amostras recobertas com filmes sobrepostos de TiNx/Cr/Ni é atribuída à menor rugosidade na superfície destas amostras.

Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2017-01-13T13:39:27Z No. of bitstreams: 1 DayaneJuliaCarvalhoDias_DISSERT.pdf: 1337745 bytes, checksum: bf916bf09b2305f7204b8b16aa64c234 (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2017-01-25T11:01:24Z (GMT) No. of bitstreams: 1 DayaneJuliaCarvalhoDias_DISSERT.pdf: 1337745 bytes, checksum: bf916bf09b2305f7204b8b16aa64c234 (MD5) / Made available in DSpace on 2017-01-25T11:01:25Z (GMT). No. of bitstreams: 1 DayaneJuliaCarvalhoDias_DISSERT.pdf: 1337745 bytes, checksum: bf916bf09b2305f7204b8b16aa64c234 (MD5) Previous issue date: 2016-07-01 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior (CAPES) / Esta disserta??o empreendeu um estudo demogr?fico do comportamento da mortalidade no Rio Grande do Norte no s?culo XIX, mais precisamente, entre 1801 e 1870. Ela contribui para um conjunto ainda escasso de trabalhos no Brasil que se dedicam ao estudo demogr?fico do per?odo de pr?-transi??o, ou seja, uma fase anterior ao in?cio do decl?nio dos n?veis de mortalidade e de natalidade. Ademais, esse trabalho representou um desafio ao propor uma an?lise quantitativa e de emprego de t?cnicas demogr?ficas utilizando dados que n?o foram delineados propriamente para esses fins. Contextualmente, o s?culo XIX foi marcado pela ocorr?ncia de doen?as epid?micas devido, principalmente, ?s p?ssimas condi??es sanit?rias e de assist?ncia m?dica, e que desempenharam papel importante na estrutura de causas de ?bito do per?odo. No caso do Rio Grande do Norte s?o elencadas pela literatura a atua??o importante de doen?as como var?ola, c?lera e febre amarela. Tendo em vista as limita??es inerentes aos dados hist?ricos sobre popula??o e contagem de ?bitos, esse estudo aplicou t?cnicas demogr?ficas espec?ficas para corre??o e estima??o dos indicadores de mortalidade. Devido ? disponibilidade de informa??es de popula??o e ?bitos totais e por grupo et?rio, foram conduzidas an?lises para cinco pontos no tempo (1801, 1805, 1839, 1846 e 1870). An?lises preliminares indicaram que o melhor m?todo para a corre??o do sub-registro da mortalidade adulta foi o M?todo de Growth Balance de Brass (1975). Para estimar a mortalidade infanto-juvenil, optou-se por utilizar uma fun??o de mortalidade j? existente, utilizando-se como crit?rio de escolha aquela que mais se aproximou da fun??o de mortalidade estimada para mortalidade adulta. Ap?s a an?lise de diversos n?veis das tabelas de vida de Coale e Demeny (1996) do modelo oeste (n?vel 6) e leste (n?vel 18), e de 19 fun??es de mortalidade de diferentes pa?ses dispon?veis no site The Human Mortality Database, a fun??o mais aproximada foi a da Isl?ndia em 1850. Assim, aplicou-se o m?todo de padroniza??o indireta para ajustar o n?vel da mortalidade e obteve-se uma nova fun??o de mortalidade para o estado do Rio Grande do Norte. Entre os principais resultados verificou-se que a taxa espec?fica da mortalidade do Rio Grande do Norte apresentou altos n?veis de mortalidade na inf?ncia entre crian?as de zero a quatro anos, e na popula??o adulta observou-se uma alta mortalidade nas idades acima de 50 anos. A expectativa de vida ao nascer foi de 32,3 anos, uma estimativa semelhante ao que Mortara (1941) encontrou para o Brasil em 1870 (esperan?a de vida de 32,7 anos) e 1890 (esperan?a de vida de 30,6 anos). De um modo geral, os resultados encontrados indicam congru?ncia entre o padr?o et?rio estimado para a mortalidade com crian?as e idosos sendo mais afetados, e o padr?o et?rio de mortalidade t?pico de regi?es afetadas por epidemias como as registradas para o Rio Grande do Norte ao longo do s?culo XIX. Sugere-se que trabalhos futuros seja aprofundado o estudo da mortalidade no Rio Grande do Norte, com a produ??o de novas estimativas com base em outras fontes documentais e censit?rias que busquem especificar ainda mais o caso da mortalidade da regi?o em estudo no mesmo per?odo pr?-transi??o demogr?fica. / This dissertation undertook a demographic study of mortality in Rio Grande do Norte during the nineteenth century, more precisely, between 1801 and 1870. It contributes to a still scarce set of studies in Brazil that are dedicated to the pre-demographic transition. Moreover, this work represented a challenge to propose a quantitative and employment demographic analysis techniques using data that were not designed specifically for these purposes. Contextually, the nineteenth century was marked by the occurrence of epidemic diseases, mainly due to poor sanitary conditions and medical care, and that played an important role in the causes of death structure of the period. In the case of Rio Grande do Norte the literature points to infeccious diseases such as smallpox, cholera and yellow fever playing a import role along the nineteenth century. Given the inherent limitations of historical data on population and deaths count, this study applied specific demographic techniques for correction and estimation of mortality indicators. Due to the availability of population information and total deaths and age group, analyzes were conducted to six points in time (1801, 1805, 1839, 1846 and 1870). Preliminary analysis indicated that the best method for correcting the underreporting of adult mortality was the Growth Balance Brass Method (1975). To estimate child mortality, was chosen an existing mortality function, using as criteria the one closest to adult mortality function. After analyzing various levels of life tables of Coale and Demeny (1996) western model (level 6) and east (level 18), and 19 mortality functions of different countries available on the site The Human Mortality Database, the function chosen was the Iceland in 1850. So we applied the indirect standardization method to adjust the level of mortality and obtained a new mortality to the Rio Grande do Norte. It was found that the specific rate of mortality of Rio Grande do Norte showed high levels of infant mortality among children aged zero to four years and in adults there was a high mortality at ages above 50 years. Life expectancy at birth was 32.3 years, a similar estimate to what Mortara (1941) found for Brazil in 1870 (life expectancy of 32.7 years) and 1890 (life expectancy of 30.6 years). In general, the results indicate congruence between the mortality age pattern estimated (children and the elderly as the most affected) and the mortality age pattern typical of areas affected by epidemics such as registered to Rio Grande do Norte over XIX century. It is suggested that future work be deepened the study of mortality in Rio Grande do Norte, with the production of new estimates based on other documentary and census sources that seek to further specify the case of mortality of the study area in the same period pre-demographic transition.

A corrosão é um fenômeno de interface que deteriora um metal através de reações químicas ou eletroquímicas, sendo caracterizada como um processo espontâneo, onde os materiais são transformados do estado metálico para uma forma combinada, decorrente da interação dos compostos metálicos com as substâncias do meio que estão inseridos. Como os prejuízos oriundos de processos corrosivos são elevados (estimativas mostram que os valores variam em torno de 3% a 4% do PIB de uma nação), estudos que minimizem estes processos são de vital importância econômica. Nos últimos anos, diversas pesquisas foram realizadas com o intuito de estudar superfícies hidrofóbicas e super-hidrofóbicas devido à sua função de autolimpeza, baixa aderência de contaminantes e proteção contra os efeitos corrosivos. Estudos recentes propõem a utilização de ácidos carboxílicos como percussores à formação destas camadas protetoras, sendo que melhores resultados foram obtidos utilizando ácidos carboxílicos de cadeias longas (acima de 11 carbonos). O ácido n-tetradecanóico (CH3(CH2)12COOH) pode ser utilizado sobre cobre e, após 10 dias de imersão em solução alcoólica de 0,06 mol/L, uma película super-hidrofóbica é formada sob o substrato, porém as características superficiais do metal são afetadas e uma camada esverdeada de carboxilato de cobre é formada. O presente trabalho, além de comprovar o efeito protetor desta camada superhidrofóbica formada, propôs a utilização do ácido n-tetradecanóico em um tratamento superficial, de forma a atuar como uma película protetora contra processos corrosivos, considerando curtos períodos de imersão em solução de ácido mirístico de forma a preservar as características superficiais do metal utilizado e torná-lo comercialmente e esteticamente mais atrativo. Os metais avaliados foram: cobre, latão e aço carbono. As técnicas eletroquímicas empregadas para a avaliação da película formada foram: curva de polarização, resistência de polarização linear (Rp) e espectroscopia de impedância eletroquímica (EIE). Medidas de ângulo de contato foram realizadas a fim de comprovar a viii hidrofobicidade do filme formado e espectroscopia de infravermelho e Raman, além da difratometria de raios X, a fim de caracterizar sua composição química. Melhores resultados foram obtidos para cobre, onde os ensaios comprovaram um aumento da hidrofobicidade da superfície metálica à medida que se aumentava o tempo de imersão dos corpos-de-prova em solução alcoólica 0,06 mol/L de ácido ntetradecanóico, atingindo valores de 116,1o e 149,8o após, respectivamente, 12 horas e 5 dias de imersão. Além disso, através de medidas de espectroscopia de impedância eletroquímica, também foi avaliado o grau de proteção da película hidrofóbica formada com relação ao substrato puro, sendo observado um aumento na proteção da superfície após 12 horas de imersão. / Corrosion is an interface phenomenon that deteriorates a metal by chemical or electrochemical reactions. It is characterized as a spontaneous process, where materials are transformed from the metallic state to a combined form. As corrosive processes damages are high (estimates show that the values vary around 3% to 4% of a nation GDP), studies that minimize corrosion reactions are of vital economic importance. Recently, several studies were performed in order to study hydrophobic and superhydrophobic layers due to its self-cleaning function, low adherence of contaminants and protection against corrosive effects. Recent studies propose the use of carboxylic acids as precursors to the formation of such protective layers, with best results being obtained using long chain carboxylic acids (up to 11 carbons). Over copper, the usage of n-tetradecanoic acid (CH3(CH2)12COOH) has showed good results after 10 days immersion in 0.06 mol/L ethanolic solution. Experimental results proved that the super hydrophobic surface could improve significantly the corrosion resistance of copper, although the surfaces have been strongly modified and a green oxidation layer (which is a copper carboxylate) has been formed over the etched copper surface. Besides proving the protective effect of the super-hydrophobic layer formed, this work also studied the use of n-tetradecanoic acid as a temporary protective layer, considering short immersion periods. In this way, the metal surface characteristics were preserved. The metals studied were: copper, brass and carbon steel. The electrochemical techniques employed for evaluation of the formed film were: polarization curves, linear polarization resistance (Rp) and electrochemical impedance spectroscopy (EIS). Contact angle measurements were performed to prove the hydrophobicity of the film and X-ray diffraction, Raman and Infrared spectroscopy were also utilized to characterize its composition. x Test samples of these metals were immersed, at ambient temperature, in 0.06 mol/L of n-tetradecanoic ethanolic solution, for different immersion periods, in order to monitor the formation of the protective layer and its hydrophobicity. Furthermore, in order to study the formation and persistence of the formed film, electrochemical tests were also performed in 3.5 wt. % NaCl solution. The results obtained for copper demonstrate an increase of the metal surface hydrophobicity for longer immersion time in 0.06 mol/L n-tetradecanoic acid solution, reaching values of 116.1o and 149.8o after, respectively, 12 hours and 5 days of immersion. Furthermore, the degree of protection of hydrophobic film was also evaluated by electrochemical impedance spectroscopy measurements and the best results were obtained for 12hs of immersion.