Over the past few decades various models of different formats have been developed to correctly evaluate and predict the strength of materials. However, these models are limited in certain environmental conditions in implementing the effect of material's thickness into their models. As such an there was a need to consider the basics of mechanical engineering and to try and define the trend, thickness has upon the behaviour of materials with respect to environmental conditions. The work consisted of a representation of tensile testing testing of common engineering alloys across a wide range of temperature, strain rate and thickness. Acquisition of high strain rate data and extended strain data (split-hopkinson, bulge forming and plane strain compression). A review of existing graphical techniques and limited applications using strength reduction factors, as well as applying the accepted empirical formulae, Johnson-Cook, Armstrong-Zerrili, Ramberg-Osgood and Hollomon. Later, recognising a need for a new approach as with a universal (quartic) polynomial fit to all plastic flow curves in which coefficients are T, ε̇ and t̄ dependant. Adoptation of a common numerical procedure for strain intercept ε0 and cut-off instability co-ordinates (σi, εi)- each as the solution to the roots of a quartic. Therefore, a proposal of the flow curve tables allowing interpolation and extrapolation, a numerical representation of any previous "Atlas of Curves". Subsequently, leading to reconstruction of the full stress-strain curve with the addition of elastic strain calculated from the modulus applicable to the specific test condition by further testing of these data from literature; both improving the existing and producing new empirical and simulation based models to analyse the materials, which will be subjected to dynamic loading as well as temperature and strain rates variations. The main objective of the work, was involved in creating a polynomial fit to describe the three physical conditions in terms of coefficients and to verify the findings in a FEA package, ABAQUS. A new process in reading the stress-strain data. By means of such development an instability study of strain limits based on Considére criteria was developed which illustrated the ways to prolong the instability limit. A secondary study of this work relates to creating a bridge between the micro-structure and macro-structure of the tested materials. A series of correlations and trends were developed to further signify the shift in micro-structural restructuring, whilst the material is under load. Another important aspect of the work consists, of carrying out an analytical study on Ramberg-Osgood equation. Ramberg-Osgood equation has been at the forefront of many engineering advancement. However it can yet be improved and reformatted by means of defining a set value for its variable constants. As such a fix ƞt value based on a best-fit approach was developed which was analytically tested.

Transition-metal-catalyzed asymmetric hydrogenation is one of the most efficient, straightforward, and well-established methods for preparing enantiomerically enriched compounds. Over the past decades, significant progress has been made with iridium, rhodium and ruthenium complexes to asymmetric hydrogenate a selection of olefins, such as, α,β-unsaturated carboxylic acid derivatives, ketones, imines and phosphonates. Although these metals have been applied successfully in the hydrogenation of olefins, they differ in their substrate tolerance.  Ruthenium and rhodium based catalysts require a coordinating group in the vicinity of the C=C bond. However, iridium based catalysts do not require this coordinating group, hence, asymmetric hydrogenation with iridium catalysts has been widely used for both functionalized and unfunctionalized olefin substrates. This thesis focuses on expanding the substrate scope for asymmetric hydrogenation using chiral N,P-ligated iridium catalysts. Papers I and II investigate the asymmetric hydrogenation of prochiral N-heterocyclic compounds prepared by ring-closing metathesis using the iridium catalysts developed in our group.  These substrates are interesting as they bear resemblance to pharmaceutically active compounds and therefore have tremendous value in medicinal chemistry.  Excellent enantioselectivities, up to >99% ee and conversions were obtained. In papers III and IV we synthesized many unsaturated acyclic and cyclic sulfones with varying substitution patterns.  The sulfones were subjected to hydrogenation using our N,P-ligated iridium catalysts, producing the chiral sulfone products in high enantiomeric excess (up to 99% ee). This methodology was combined with the Ramberg-Bäcklund reaction, offering a novel route to chiral allylic and homoallylic compounds. In addition to obtaining these chiral compounds in good yields, no decrease in enantiomeric excess was observed after the Ramberg-Bäcklund reaction. This strategy has been applied in the preparation of the chiral building block for renin inhibitors.

A presente tese apresenta uma nova síntese de vários vinil sulfóxidos, importantes dienófilos e aceptores de Michael, a partir de matéria prima facilmente disponível - álcoois ou haletos benzílicos. Dois passos novos nesta síntese, a sulfenilação de benzil i-propil sulfonas e o rearranjo de Ramberg-Bäcklund de α-metiltio sulfonas correspondentes resultantes da sulfenilação, são investigados. Os vinil sulfetos, obtidos neste último passo, podem ser também sintetizados por outros métodos. Uma grande variedade dos mesmos foi recolhida da literatura e agrupada em diversas classes, considerando as reações envolvidas. A falta de um \"review\" deste tipo na literatura toma a nossa revisão bibliográfica de grande utilidade. A síntese por nós desenvolvida pode ser apresentada pelo esquema abaixo indicado: (Veja esquema no arquivo PDF) Este esquema mostra que além das duas principais reações por nós já mencionadas, sulfenilação e rearranjo de Ramberg-Bäcklund, podem ser também destacadas diversas reações de oxidação de sulfetos que diferem no emprego de reagentes oxidantes e de condições experimentais. O esquema indica também que as tentativas de obtenção de vinil sulfóxidos pela oxidação prévia de sulfonas α-sulfeniladas aos sulfóxidos correspondentes e rearranjo de Ramberg-Bäcklund destes últimos, foram infrutíferas. Um número considerável de compostos novos foram por nós sintetizados, entre eles cinco benzil i-propil sulfonas, nove sulfonas sulfeniladas, quatro vinil sulfetos, três vinil sulfóxidos e cinco α-sulfinil sulfonas, além de quatro sulfetos intermediários. Além da parte sintética, a presente tese apresenta também uma discussão sobre as estabilidades e reatividades relativas de intermediários envolvidos nas duas reações investigadas: os α-sulfonil e α- metiltio α-sulfonil carbânions, destacando a influência do grupo metiltio. / This thesis presents a new synthesis of some vinyl sulfoxides, important dienophiles and Michael acceptors, starting from the easily available materials, benzylic alcohols or halides. Two new reaction steps of this synthesis, sulfenylation of benzyl i-propyl sulfones leading to the corresponding α-methylthio sulfones and Ramberg-Bäcklund rearrangement of the latter to give vinyl sulfides, are investigated. A great number of methods of synthesis of vinyl sulfides, described in the literature, were collected and selected according to the type of reaction which they envolve. It is noteworthy that such literature review could not be found in the literature. The scheme below shows the reaction steps of our synthesis of vinyl sulfides. (See scheme in file) It may be seen in the scheme that, beside the already mentioned two main reactions, sulfenylation and Ramberg-Bäcklund rearrangements, several oxidations of sulfides were also performed, which differ in oxidating reagents and experimental conditions. The scheme also indicates that the efforts to obtain the vinyl sulfoxides by previous oxidation of the α-sulfenylated sulfones to the corresponding sulfoxides and Ramberg-Bäcklund rearrangement of the latter, were unsuccessful. A considerable number of new compounds were synthesized, betwen them five benzyl i-propyl sulfones, nine α-sulfenylated sulfones, four vinyl sulfides, three vinyl sulfoxides, five sulfinyl sulfones, and four intermediate sulfides. The thesis presents also a discussion on the relative stability and reactivity of the reaction intermediates - α-sulfonyl and α-methylthio, α-sulfonyl carbanions, enhancing the influence of α-methylthio group.

A presente tese apresenta uma nova síntese de vários vinil sulfóxidos, importantes dienófilos e aceptores de Michael, a partir de matéria prima facilmente disponível - álcoois ou haletos benzílicos. Dois passos novos nesta síntese, a sulfenilação de benzil i-propil sulfonas e o rearranjo de Ramberg-Bäcklund de α-metiltio sulfonas correspondentes resultantes da sulfenilação, são investigados. Os vinil sulfetos, obtidos neste último passo, podem ser também sintetizados por outros métodos. Uma grande variedade dos mesmos foi recolhida da literatura e agrupada em diversas classes, considerando as reações envolvidas. A falta de um \"review\" deste tipo na literatura toma a nossa revisão bibliográfica de grande utilidade. A síntese por nós desenvolvida pode ser apresentada pelo esquema abaixo indicado: (Veja esquema no arquivo PDF) Este esquema mostra que além das duas principais reações por nós já mencionadas, sulfenilação e rearranjo de Ramberg-Bäcklund, podem ser também destacadas diversas reações de oxidação de sulfetos que diferem no emprego de reagentes oxidantes e de condições experimentais. O esquema indica também que as tentativas de obtenção de vinil sulfóxidos pela oxidação prévia de sulfonas α-sulfeniladas aos sulfóxidos correspondentes e rearranjo de Ramberg-Bäcklund destes últimos, foram infrutíferas. Um número considerável de compostos novos foram por nós sintetizados, entre eles cinco benzil i-propil sulfonas, nove sulfonas sulfeniladas, quatro vinil sulfetos, três vinil sulfóxidos e cinco α-sulfinil sulfonas, além de quatro sulfetos intermediários. Além da parte sintética, a presente tese apresenta também uma discussão sobre as estabilidades e reatividades relativas de intermediários envolvidos nas duas reações investigadas: os α-sulfonil e α- metiltio α-sulfonil carbânions, destacando a influência do grupo metiltio. / This thesis presents a new synthesis of some vinyl sulfoxides, important dienophiles and Michael acceptors, starting from the easily available materials, benzylic alcohols or halides. Two new reaction steps of this synthesis, sulfenylation of benzyl i-propyl sulfones leading to the corresponding α-methylthio sulfones and Ramberg-Bäcklund rearrangement of the latter to give vinyl sulfides, are investigated. A great number of methods of synthesis of vinyl sulfides, described in the literature, were collected and selected according to the type of reaction which they envolve. It is noteworthy that such literature review could not be found in the literature. The scheme below shows the reaction steps of our synthesis of vinyl sulfides. (See scheme in file) It may be seen in the scheme that, beside the already mentioned two main reactions, sulfenylation and Ramberg-Bäcklund rearrangements, several oxidations of sulfides were also performed, which differ in oxidating reagents and experimental conditions. The scheme also indicates that the efforts to obtain the vinyl sulfoxides by previous oxidation of the α-sulfenylated sulfones to the corresponding sulfoxides and Ramberg-Bäcklund rearrangement of the latter, were unsuccessful. A considerable number of new compounds were synthesized, betwen them five benzyl i-propyl sulfones, nine α-sulfenylated sulfones, four vinyl sulfides, three vinyl sulfoxides, five sulfinyl sulfones, and four intermediate sulfides. The thesis presents also a discussion on the relative stability and reactivity of the reaction intermediates - α-sulfonyl and α-methylthio, α-sulfonyl carbanions, enhancing the influence of α-methylthio group.

Exergy utilization calculations have been in the past repeatedly used to quantify the quality and quantity of energy used in thermal energy processes. This thesis is an attempt to derive a common language exergy utilization and compare for the first time two entirely different manufacturing processes, namely material processing by a mechanical method of straining of the material and simple heating of the same mass of the material using exergy utilization as a metric. The exergy utilization of material processing is determined by performed work and utilized heat transfer using 1) Ramberg-Osgood equation and 2) Lumped heat capacitance method. A comparison of these two methods is presented.

In this paper we present novel analytic and finite element solutions to 1-D straight rods made of Ramberg-Osgood and Hollomon type materials. These material models are studied because they are a more accurate representation of the material properties of certain metals used often in manufacturing than the simpler composite linear types of stress/strain models. Here, various types of loads are considered and solutions are compared against some linear models. It is shown that the nonlinear models do have manageable solutions, which produce important differences in the results - attributes which suggest that these models should take a more prominent place in engineering analysis.

O presente trabalho tem como objetivo investigar o comportamento elasto-plástico em baixas deformações do fio máquina laminado em aço AISI 1045 destinado a trefilação e processos subsequentes de beneficiamento. Inicialmente, foi obtido material de quatro diferentes lotes de fabricação, sendo todas as amostras retiradas após a etapa de pré-endireitamento do processo de trefilação. O material foi caracterizado através de análise da composição química, metalográfica, determinação de tamanho de grão e segregação. Além disso, o comportamento elasto-plástico do material em ciclos de tração e compressão foi investigado, identificando-se o efeito Bauschinger para três diferentes temperaturas. Os modelos numéricos de Ramberg-Osgood e Ludwig-Hollomon foram utilizados para a definição de uma modelo numérico da curva para utilização em trabalhos futuros de simulação computacional. O modelo de Ludwig-Hollomon foi avaliado como mais satisfatório para baixas deformações e foi então utilizado para o cálculo da curva média de quatro lotes. A partir de curvas de escoamento de aço similar obtidas da literatura, foi possível obter-se uma extrapolação da curva para diferentes taxas de deformação, além da taxa de 0.05s-1, original dos ensaios: 1.6 s-1, 8 s-1, e 40 s-1. / The purpose of this work is to investigate the elastic-plastic behavior at low strains of steel rolled coil AISI 1045 intended for cold-drawing and subsequent processes. First, the material was withdrawn from four different manufacturing batches and all samples were taken from the pre-straightening process step. The material was characterized by means of chemical and metallography analysis, grain size and segregation. Furthermore, the elastic-plastic behavior in tension and compression cycles was investigated and the Bauschinger effect was identified for three different temperatures. The numerical models Ramberg-Osgood and Ludwig-Hollomon were the models used in this work to define the flow curve which can be used in future computer simulation works. The analysis showed that the Ludwig-Hollomon model is more adequate for low strains ranges. Ludwig-Hollomin was used to calculate the average flow curve based on the curves of the four batches. By using literature flow curves of similar steels, it was possible to make an extrapolation and to obtain flow curves at different strain rates beyond the experimental one: 1.6 s-1, 8 s-1, e 40 s-1.

Organosulfur compounds have been used by humans for centuries and played a pivotal role in shaping our history. The chemistry presented herein deals primarily with three distinct organic transformations involving organosulfur species. The three transformations are used in tandem to complete the synthesis of natural products. The first chapter examines a new diastereoselective alkylation reaction of sulfenate anions with stereoinduction provided by chiral amino iodides. A series of β-amino sulfoxides are accessed in good yields and selectivities from alkylations with the corresponding lithium arene- and E-1-alkenesulfenate anions. The relative reactivity of different electrophiles towards a selection of lithium sulfenate anions was also evaluated by performing competition experiments. In the second chapter 1,2-dibromotetrachloroethane (C2Br2Cl4) was evaluated as a more economical halogenating agent for the in-situ Ramberg-Bäcklund rearrangement (RBR). A series of trans-stilbenoids were successfully synthesized using this protocol in excellent yields. The new RBR system also worked well for dialkyl and cyclic substrates, but the reaction was plagued by polyhalogenation for hexyl benzyl sulfone. The methodology was extended to the formal total synthesis of natural polyphenol E-resveratrol. Chapter three investigates asymmetric aza-Michael reactions of chiral β-amino sulfoxides/sulfones to synthesize thiomorpholine S-oxides and S,S-dioxides, respectively. Remarkably, cyclizations of the β-amino sulfoxides provide the trans- 3,5-substituted heterocycles, while the β-amino sulfones provide the complementary cis-3,5-substituted heterocycles. The aza-Michael chemistry was exploited along with the sulfenate and RBR protocols to access two ant venom alkaloids. / NSERC

O presente trabalho tem como objetivo investigar o comportamento elasto-plástico em baixas deformações do fio máquina laminado em aço AISI 1045 destinado a trefilação e processos subsequentes de beneficiamento. Inicialmente, foi obtido material de quatro diferentes lotes de fabricação, sendo todas as amostras retiradas após a etapa de pré-endireitamento do processo de trefilação. O material foi caracterizado através de análise da composição química, metalográfica, determinação de tamanho de grão e segregação. Além disso, o comportamento elasto-plástico do material em ciclos de tração e compressão foi investigado, identificando-se o efeito Bauschinger para três diferentes temperaturas. Os modelos numéricos de Ramberg-Osgood e Ludwig-Hollomon foram utilizados para a definição de uma modelo numérico da curva para utilização em trabalhos futuros de simulação computacional. O modelo de Ludwig-Hollomon foi avaliado como mais satisfatório para baixas deformações e foi então utilizado para o cálculo da curva média de quatro lotes. A partir de curvas de escoamento de aço similar obtidas da literatura, foi possível obter-se uma extrapolação da curva para diferentes taxas de deformação, além da taxa de 0.05s-1, original dos ensaios: 1.6 s-1, 8 s-1, e 40 s-1. / The purpose of this work is to investigate the elastic-plastic behavior at low strains of steel rolled coil AISI 1045 intended for cold-drawing and subsequent processes. First, the material was withdrawn from four different manufacturing batches and all samples were taken from the pre-straightening process step. The material was characterized by means of chemical and metallography analysis, grain size and segregation. Furthermore, the elastic-plastic behavior in tension and compression cycles was investigated and the Bauschinger effect was identified for three different temperatures. The numerical models Ramberg-Osgood and Ludwig-Hollomon were the models used in this work to define the flow curve which can be used in future computer simulation works. The analysis showed that the Ludwig-Hollomon model is more adequate for low strains ranges. Ludwig-Hollomin was used to calculate the average flow curve based on the curves of the four batches. By using literature flow curves of similar steels, it was possible to make an extrapolation and to obtain flow curves at different strain rates beyond the experimental one: 1.6 s-1, 8 s-1, e 40 s-1.

O presente trabalho tem como objetivo investigar o comportamento elasto-plástico em baixas deformações do fio máquina laminado em aço AISI 1045 destinado a trefilação e processos subsequentes de beneficiamento. Inicialmente, foi obtido material de quatro diferentes lotes de fabricação, sendo todas as amostras retiradas após a etapa de pré-endireitamento do processo de trefilação. O material foi caracterizado através de análise da composição química, metalográfica, determinação de tamanho de grão e segregação. Além disso, o comportamento elasto-plástico do material em ciclos de tração e compressão foi investigado, identificando-se o efeito Bauschinger para três diferentes temperaturas. Os modelos numéricos de Ramberg-Osgood e Ludwig-Hollomon foram utilizados para a definição de uma modelo numérico da curva para utilização em trabalhos futuros de simulação computacional. O modelo de Ludwig-Hollomon foi avaliado como mais satisfatório para baixas deformações e foi então utilizado para o cálculo da curva média de quatro lotes. A partir de curvas de escoamento de aço similar obtidas da literatura, foi possível obter-se uma extrapolação da curva para diferentes taxas de deformação, além da taxa de 0.05s-1, original dos ensaios: 1.6 s-1, 8 s-1, e 40 s-1. / The purpose of this work is to investigate the elastic-plastic behavior at low strains of steel rolled coil AISI 1045 intended for cold-drawing and subsequent processes. First, the material was withdrawn from four different manufacturing batches and all samples were taken from the pre-straightening process step. The material was characterized by means of chemical and metallography analysis, grain size and segregation. Furthermore, the elastic-plastic behavior in tension and compression cycles was investigated and the Bauschinger effect was identified for three different temperatures. The numerical models Ramberg-Osgood and Ludwig-Hollomon were the models used in this work to define the flow curve which can be used in future computer simulation works. The analysis showed that the Ludwig-Hollomon model is more adequate for low strains ranges. Ludwig-Hollomin was used to calculate the average flow curve based on the curves of the four batches. By using literature flow curves of similar steels, it was possible to make an extrapolation and to obtain flow curves at different strain rates beyond the experimental one: 1.6 s-1, 8 s-1, e 40 s-1.