Universiẗat, Diss., 2003--Bonn.

Th.--Sci. math.--Besançon, 1984. N°: 183.

Bidentate ligands are a commonly used class of ligands in catalysis that generate highly-active and selective catalysts. Such bidentate ligands, however, often suffer from synthetic challenges, which can be alleviated by the use of simpler monodentate ligands that assemble through non-covalent interactions to mimic the structure of bidentate ligands at the metal center. To produce a strongly assembled catalyst complex, the Hamilton receptor motif was utilized. Hamilton receptors form six hydrogen bonds with complementary guests and have binding affinities for barbiturates of up to 104 M-1 in CDCl3. Complete bifurcation of the Hamilton scaffold produces a modular ligand structure that allows for modification of either end of the supramolecular ligand structure. Similarly, the barbiturate guest can be synthetically altered creating both chiral guests and guests with differing amounts of steric bulk. Both experimental titration data and density functional theory calculations show that steric bulk discourages binding of the guest while a pre-organized host encourages guest inclusion. Electronic effects on the bifurcated Hamilton system were studied by varying the electron donating or withdrawing ability of the benzamide moiety on the host molecule. Electron withdrawing moieties produce more acidic amide hydrogens on the host which are able to participate in stronger hydrogen bonds with the guest resulting in a stronger host-guest complex. The effects of substitutions on the barbiturate guest were examined as well, and increased steric bulk on the guest resulted in decreased affinities with the host. The bifurcated Hamilton receptor ligands were examined in the palladium-catalyzed Heck reaction of iodobenzene with butyl acrylate. Pd2(OAc)4 was used as a control and all reaction yields with the diphenylphosphine ligand-stabilized Pd were greater than or equal to those obtained with Pd2(OAc)4 alone. The reaction rates did not correlate with the determined binding constants, suggesting that phosphine substitution on the guest plays a larger role than affinity of the complex for the guest. Reaction temperatures were varied, and at lower temperatures the yields increased implying that the strength of the hydrogen bonds between the metal complex and the guest does play a secondary role in the catalysis. This dissertation includes previously published co-authored material.

This thesis constitutes a piece of practice-led research: its principal research aim is to reflect on, analyse, and explore the conceptual, cultural, and artistic framework within which the offered artworks stand. The introduction is designed to provide an overview of both the central ideas to be discussed and the methodology to be deployed. It will also offer a snapshot of the structure of the text as a whole. As I will indicate, both method and content can be approached via a common guiding form: that of the fixed bind or knot. I will begin by introducing those concepts as they apply both to my own works and to those with which I have brought them into relation. My central concern is with the way in which the imagination forms connections and associations, the way objects or visions are gathered together in the imagination, and the way in which such ties might form knots, might amass or fix within them. I use the terms ‘binds’ and ‘bonds’ to refer to all such relations: to investigate these binds is to investigate the architecture of the imagination. My aim is to explore the way in which the structure of such binds might be present or affirmed in a physical object. In this context, the sculptures I have submitted can thus be understood as points of consolidation, points around which imagination amasses, and points at which binds accrue and abide: they are forms wrought and fixed, but not motionless, in the imagination. In this sense, from a theoretical perspective, to reflect on the sculptures is to reflect on what it means for objects or visions to bind and fixate in the imagination and for sculptors to realise them. For example, the first sculpture arises from attempting to make a seamless and ongoing circle of rope from lengths of hair. Here a material that stops once unbound from the head is repeatedly knotted. The longer binds thereby arise through a process of perpetual repetition in seeking to form a perfect bind; I juxtapose this vision of repetition with, for example, Kierkegaard’s work on that concept in order to analyse the nature of such a joint and impulse. As I have introduced the term, ‘binds’ therefore carries a double weight; it refers both to the structure of the imagination and to the sculptural connections that affirm it. The primary aim of this thesis is to investigate the interplay between these two aspects in both my own work and in that of a number of authors and artists.

Made available in DSpace on 2015-12-10T14:23:02Z (GMT). No. of bitstreams: 0 Previous issue date: 2013-03-07. Added 1 bitstream(s) on 2015-12-10T14:27:52Z : No. of bitstreams: 1 000852795.pdf: 576204 bytes, checksum: 28ede436e9367885bc3b672b1903caad (MD5) / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / A teoria de Hamilton-Jacobi geralmente é apresentada como uma extensão da teoria de Hamilton através das transformações canônicas. No entanto, o matemático Constantin Carathéodory mostrou que essa teoria, sua existência e validade, independem do formalismo hamiltoniano. Neste trabalho, apresentaremos a abordagem de Carathéodory para a teoria de Hamilton-Jacobi. Partindo desse procedimento, construiremos uma teoria de vínculos para que se possa resolver problemas com vínculos involutivos e não-involutivos. Para isso, analisaremos a integrabilidade das equações e introduziremos a operação dos parênteses generalizados que, no lugar do parênteses de Poisson, passará a descrever a dinâmica de sistemas vinculados. Mostraremos uma aplicação dessa teoria de vínculos no modelo BF da teoria de campos. Para finalizar, trataremos da Termodinâmica Axiomática de Carathéodory e também da teoria de Hamilton-Jacobi na Termodinâmica, o que é válido para ilustrar a grande abrangência desse formalismo / The Hamilton-Jacobi theory is usually presented as an extension of the Hamilton's theory through the canonical transformations. However, the mathematician Constantin Carathéodory showed this theory, its existence and validity, is independent of the Hamiltonian formalism. In this work, we present the Caratheodory's approach to the Hamilton-Jacobi theory. From this procedure, we build a theory of constraints which can solve problems with involutive and non-involutive constraints. For this, we analyze the integrability of the equations and introduce the operation of the generalized brackets that, instead of Poisson brackets, will describe the dynamics of constrained systems. We show an application of this theory in BF model of the field theory. Finally, we will discuss the Carathéodory's Axiomatic Thermodynamics and also show the Hamilton-Jacobi theory in Thermodynamics, which is valid to illustrate the wide coverage of this formalism / CNPq: 133488/2011-0

Made available in DSpace on 2015-09-17T15:25:11Z (GMT). No. of bitstreams: 0 Previous issue date: 2015-02-19. Added 1 bitstream(s) on 2015-09-17T15:49:10Z : No. of bitstreams: 1 000846310_20151231.pdf: 154526 bytes, checksum: 0758a595ef94b62272723a08448eaedd (MD5) Bitstreams deleted on 2016-01-04T10:26:35Z: 000846310_20151231.pdf,. Added 1 bitstream(s) on 2016-01-04T10:28:27Z : No. of bitstreams: 1 000846310.pdf: 638836 bytes, checksum: 455c057fa42c2de1060101490372b4fe (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Neste trabalho caracterizaremos sistemas dinâmicos na forma dos chamados domínios estratificados. Bressan e Hong[9] foram os primeiros a definir e trabalhar em domínios estratificados. Grosso modo, estes são uma coleção de domínios disjuntos, cada um tendo sua própria dinâmica; mas não se exige que seus domínios sejam proximamente suaves e nem wedged. Estes termos foram introduzidos por P. Wolenski e R. Barnard em[10]. Primeiramente, estabeleceremos condições Hamiltonianos para caracterizar invariância fraca e forte para sistemas não Lipschitz em domínios estratificados. Depois, estudamos condições Hamiltonianas para sistemas fracamente e fortemente decrescentes e apresentamos condições que garantem a estabilidade assintótica global para uma dinâmica estratificada e finalmente apresentamos o problema tipo Mayer em domínios estratificados em que mostramos que a função valor e a única solução semicontínua inferior de uma generalização adequada da clássica equação Hamilton-Jacobi-Bellman, para a dinâmica estratificada / In this work will characterize dynamical systems in the form of the so-called strati ed domain. Bressan and Hong [9] were the rst to de ne and work in strati ed domains. Roughly speaking, these are a collection of disjoint domains, each having its own dynamics; but not requiring that their domains are proximally smooth and not wedged. These terms were introduced by P. Wolenski and R. Barnard in [10]. At rst, we will establish Hamiltonian conditions to characterize weak and strong invariance for systems non-Lipschitz in strati ed domains. Secondly, we study the Hamiltonian conditions for systems weakly and strongly de- creasing and present conditions that guarantee global asymptotic stability for a strati ed dynamics and nally we present the problem Mayer type in strati ed domains where we show that the value function is the unique lower semicontinuous solution of an appropriate generalization of the classical Hamilton-Jacobi-Bellman equation for strati ed dynamics

Submitted by Gabriel Brandão de Gracia (gb9950@gmail.com) on 2018-01-31T15:49:29Z No. of bitstreams: 2 Dissertação Final.pdf: 530405 bytes, checksum: 393276cfee653f2dd2aedc610270b907 (MD5) Dissertação Final.pdf: 530405 bytes, checksum: 393276cfee653f2dd2aedc610270b907 (MD5) / Rejected by Hellen Sayuri Sato null (hellen@ift.unesp.br), reason: Favor deletar um arquivo e acrescentar o abstract on 2018-01-31T16:48:03Z (GMT) / Submitted by Gabriel Brandão de Gracia (gb9950@gmail.com) on 2018-01-31T16:56:21Z No. of bitstreams: 1 Dissertação Final.pdf: 530405 bytes, checksum: 393276cfee653f2dd2aedc610270b907 (MD5) / Approved for entry into archive by Hellen Sayuri Sato null (hellen@ift.unesp.br) on 2018-01-31T17:12:15Z (GMT) No. of bitstreams: 1 gracia_gb_me_ift.pdf.pdf: 530405 bytes, checksum: 393276cfee653f2dd2aedc610270b907 (MD5) / Made available in DSpace on 2018-01-31T17:12:15Z (GMT). No. of bitstreams: 1 gracia_gb_me_ift.pdf.pdf: 530405 bytes, checksum: 393276cfee653f2dd2aedc610270b907 (MD5) Previous issue date: 2017-02-24 / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / Ao longo desta dissertação desenvolvemos o formalismo de Hamilton-Jacobi para teorias de campo para o caso de sistemas singulares e não-singulares. Em seguida, aplicamos tal formalismo nos modelos BF em D=1+1, D=2+1 e D=3+1 dimensões a fim de caracterizar os seus espaços de fase. Mostramos que a partir desse formalismo é possível obter as simetrias locais desses modelos assim como os seus respectivos geradores. / Throughout this dissertation we develop the Hamilton-Jacobi formalism for field theories in the case of singular and non-singular systems. Next, apply such formalism on the BF models in D=1+1, D=2+1 e D=3+1 dimensions in order to characterize their phase spaces. We show from this formalism, that is possible to find the local symmetries of those models as well as their respective generators. / CNPq: 132619/2015-6

Orientador: Bruto Max Pimentel Escobar / Banca: Ana Lúcia Barbosa / Banca: Júlio César Fabris / Resumo: Neste trabalho estudamos a estrutura de vínculos da Relatividade Geral (RG) e do Equivalente Teleparalelo da Relatividade Geral (ETRG), utilizando o formalismo de Hamilton-Jacobi para sistemas singulares. Fazemos uma revisão destas duas teorias de gravitação e de suas formulações ADM, tendo em mente que ambas são construídas sobre variedades que são casos particulares da variedade de Riemann-Cartan. Revemos também o formalismo de Hamilton-Jacobi para o tratamento de sistemas singulares, fazendo em seguida a sua aplicação para as duas teorias supracitadas. Nesta análise constatamos que a invariância do ETRG por transformações de Lorentz no espaço tangente das tetradas faz com que a álgebra do vínculos seja diferente daquela obtida para a RG / Abstract: In this work we study the constraint structure of General Relativity (GR) and Teleparallel Equivalent of General Relativity (TEGR), using the Hamilton-Jacobi formalism for singular systems. We make a review of these two theories of gravitation and their ADM formulation, having in mind that both theories are built over manifolds that are particular cases of the Riemann-Cartan manifold. We also review the Hamilton-Jacobi formalism for singular systems, making its application to the cited theories. In this analysis we testify that the invariance of the TEGR under Lorentz transformations in the tangent space of the tetrads implies in a different constraint algebra than that obtained in GR / Mestre

Orientador: João Mauricio Rosario / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Mecanica / Made available in DSpace on 2018-07-22T12:11:24Z (GMT). No. of bitstreams: 1 Fenili_Andre_M.pdf: 10886441 bytes, checksum: e02c936e350afaabc08b309385e4d2ea (MD5) Previous issue date: 1997 / Resumo: Neste trabalho desenvolve-se dois modelos para estruturas flexíveis de rastreamento de membro único: um modelo para pequenas deflexões e um modelo para grandes deflexões. Tanto para um modelo quanto para o outro, utilizou-se o Princípio de Hamilton Estendido para se obter as equações dinâmicas do movimento. Estas equações são posteriormente adimensionalizadas de tal forma que um pequeno parâmetro adimensional de perturbação 'PERTENCE¿ possa ser obtido. Este parâmetro irá multiplicar todas as não linearidades de cada modelo e será o único parâmetro a se variar quando se pretende estudar casos diversos. Este pequeno parâmetro adimensional é utilizado para se verificar o grau de acoplamento entre as equações dinâmicas do movimento. Simulações são realizadas entre pequenas e grandes deflexões e comparadas enter si e com o modelo para o mesmo sistema aonde não se considera flexibilidade nenhuma. No estudo do comportamento da estrutura flexível de rastreamento realizado neste trabalho, o truncamento para a discretização das equações do movimento (método dos modos assumidos) deu-se no primeiro modo próprio do sistema viga engastada-livre / Abstract: In this work two models are developed to slewing flexible structures with just one link: a model considering small deflections and a model considering great deflections. For both models, the Extended Hamilton's PrincipIe is utilized so one can obtain the goveming euqations o fmotion. This equations are then nondimensionalized so one can obtain a smalI nondimensional perturbation parameter 'PERTENCE¿. This parameter appears multiplying alI the nonlinearities in each model and will be the only parameter one must variate when involved in the study of different cases. This smalI nondimensional parameter is utilized to verify the degrre of coupling between the dinamical equations of motion. Simulations are realized between smalI and great deflections and compared one with another and with the model to the very same system where no flexibility is considered. In the study of the behavior of the flexible structure in slewing motion realized in this work, the truncation utilized for the discretization of the equations of motion (assumed modes method) is done in the first mode of vibration of the system beam constrained-free / Mestrado / Mecanica dos Solidos / Mestre em Engenharia Mecânica

Orientador: Waldyr Alves Rodrigues Junior / Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Matematica, Estatistica e Computação Cientifica / Made available in DSpace on 2018-07-26T01:36:39Z (GMT). No. of bitstreams: 1 Carvalho_AlexandreLuisTrovonde_D.pdf: 15293549 bytes, checksum: 6f77ce91b6897c18e527e4134e109ed1 (MD5) Previous issue date: 2000 / Resumo: O propósito desta tese é estudar, sob o ponto de vista algébrico, o papel desempenhado pelos operadores diferenciais nos formalismos variacionais Lagrangeano e Hamiltoneano. Apresentamos uma aplicação simples das idéias e resultados básicos da teoria dos operadores diferenciais às álgebras de Clifford, obtendo uma relação entre os operadores diferenciais e o operador de Dirac. Introduzimos um formalismo Hamiltoneano, com base nos módulos de símbolos dos operadores diferenciais, generalizando os resultados para anéis comutativos. Nesse formalismo, encontramos importantes propriedades algébricas para a Hamiltoneana, e destacamos o colchete de Poisson como uma estrutura mais básica que a forma simplética canônica. Introduzimos o conceito de adjunta de um operador diferencial e, por meio dela, caracterizamos as formas integrais em termos das formas de Berezin. Obtemos uma seqüência espectral relacionando a cohomologia das formas integrais com a cohomologia de De Rham, tanto para variedades quanto para supervariedades. Introduzimos o conceito de Lagrangeana, e analisamos sua relação com as formas de Berezin. Nesse contexto, estudamos as leis de conservação, e obtemos um equivalente algébrico para o Teorema de Noether. Finalmente, essas construções nos encaminham rumo a uma versão algébrica para o teorema do índice. / Abstract: The purpose of this thesis is to study, from the algebraic viewpoint, the rule played by the differential operators in Lagrangian and Hamiltonian variational formalisms. We present a simple application of the basic ideas and results form the theory of differential operators to the Clifford algebras, from where we obtain a relationship between differential operators and the Dirac operator. We introduce a Hamiltonian formalism based on the symbol modules, generalizing some results to commutative rings. In this formalism we find important algebraic properties for the Hamiltonian and notice that the Poisson bracket is a more fundamental structure than the canonical sympletic form. We introduce the concept of adjoint of a differential operator and by means of it we are able to charactrize the integral forms in terms of Berezin forms. We obtain a spectral sequence relating the cohomology of integral forms to the De Rham cohomology, for both manifolds and supermanifolds. In this context, we study the con- servation laws and obtain an algebraic equivalent to the Noether theorem. Finally, these constructions direct us towards an algebraic version to the index theorem. / Doutorado / Doutor em Matemática