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Estrutura de platô na magnetização em modelos de spins frustrados
(Universidade Federal de São Carlos, 2012-10-26) Anjos, Rosana Aparecida dos; Souza, José Ricardo de; https://lattes.cnpq.br/7632326568135001
This thesis study the phase transition, forms classical and quantum models of spin frustration. The Heisenberg model of spin 1/2 with exchange anisotropy with competitive interactions between first (J1) and second (J2) neighbors, called Model J1 − J2, will be analyzed through phase diagrams where we consider several parameters, including the frustration J2 and J1 what is the delimiter between the Ising and Heisenberg models. The Ising model is also studied in this work. We apply effective field theory (EFT) in finite clusters via differential operator technique (TOD). In particular starting phase diagrams of these models allowed us to observe the state antiferromagnetic (AF) and SAF called collinear (CAF), formed by horizontal lines (vertical) and ferromagnetic oriented along the vertical direction (horizontal) chains are oriented antiparalelo and a second stage still called SAF or (CAF-1) having alternate rows in ferromagnetic and antiferromagnetic. A special brackets is made for one phase called SAF-2 or CAF-2, comprised two consecutive columns ferromagnetic and antiferromagnetic next and so on, thereby constructing a new phase. With the application of the external field we had a phenomenon capable of generating structures in plateau magnetization. The plateau phenomenon is influenced by the frustration parameter _ = J2/J1, the plateau were studied for the Ising and Heisenberg models generate different results with satisfactory conclusion. The methods and models were applied to networks in two and three dimensions.
Distribuição de combustíveis no estado de São Paulo: estruturas de governança e oportunismo
(Universidade Federal de São Carlos, 2012-10-26) Soares, Selene de Souza Siqueira; Paulillo, Luiz Fernando de Oriani e; https://lattes.cnpq.br/9919942357089937; https://lattes.cnpq.br/1373686436888322
This work is directed to the study of transactions governance adopted by fuel distributors in the State of Sao Paulo with retail market sellers or gas stations. The applied theoretical approach lies on studies of New Institutional Economics, favoring the study of Transaction Costs Economics, using attributes of transactions defined by Williansom (1979) and other studies by authors such as Ménard (2001, 2004; 2006) which emphasizes hybrids coordination devices complementary to contracts such as influence, leadership, confidence and ad hoc institutions. The supply sector study under this theoretical point of view is quite interesting, because since the begging of deregulation process in the late 1990s, the final link in this chain has brought distinct governance. Two kinds of transactions keep going on simultaneously: sales in the spot market among all distributors and no branded gas station (or so called white flag resellers), and hybrid governance structures with long-term contracts between distributors and their gas station franchisees. This has been a common strategy adopted by dominant distributors and pursued in some extent by regional distributors. In addition, the observation of governance in the sector progressively highlights the representativeness of opportunistic behavior, especially those related to fuel adulteration and acquisitions outside the exclusive arrangement of negotiations. The control decisions of such opportunistic behavior and recognition of their impact in the coordination of transactions have become essential for understanding the expected stability in this governance and their suitability as minimizing structures of transaction costs. The results of this thesis suggest that the governance structures of the transactions differ by asset specificity. Hybrid governance structure is the most common one. The control of opportunistic actions in this kind of structure has been carried out by using contractual mechanisms and complementary mechanisms to contracts. On the other side, regional distributors set transactions of lower asset specificity and use influence as the only coordinating mechanism complementary to those contracts. However, in terms of business share, transactions through market are still the most frequent ones in this segment. As for the third group of distributors, the independent ones, transactions take place uniquely through the market and the control of opportunistic actions are dispensed by them and transferred to sectorial monitoring public organizations. Delay in asserting the contracts has been the main cause of the uprising of complementary mechanisms, and its utilization has been directed basically to the protection of the specific assets in transactions, specially in the preservation of the unique trading channels, recovery of specific investments and mainly to protect its brand-specific assets. If, in one hand, the hybrid governance efficiency in the use of these mechanisms enhances the transaction costs and approaches to governance structure of hierarchical and centralised structures, on the other hand, in low asset specific transactions, relations of spot market and competitive bases of another thread are consolidated differently from the first, looking primarily for lower prices despite the appeal of quality referenced by the main specific distributors firms assets distributors: their brands.
Foucault e a transgressão do prazer na ética da psicanálise lacaniana
(Universidade Federal de São Carlos, 2012-10-26) Rodrigues, Malcom Guimarães; Simanke, Richard Theisen; https://lattes.cnpq.br/5431145327759147; https://lattes.cnpq.br/8316619833936970
L objectif est interroger les notions lacaniennes de « plaisir » et « transgression », qui a été conçu le début des années 1960, en face de la théorie foucaultienne de la « boîte à outils », pour proposer une forme de résistance en marge des dilemmes pervers qui apparaissent à l'éthique de la psychanalyse lacanienne.
Programa computacional para a avaliação da produtividade da mão de obra na execução de sistemas prediais
(Universidade Federal de São Carlos, 2012-10-26) Nascimento, Thiago Augusto do; Paliari, José Carlos; https://lattes.cnpq.br/9387796929252598; https://lattes.cnpq.br/4845828457193556
The increased productivity of labor is an important factor for businesses in general face a scenario of competitiveness. In Construction there is a great opportunity for improving the productivity of labor and among the services that deserve attention in this issue, we highlight the implementation of Building Systems Hydraulic and Fuel Gas Piping (SPHSGC). However, few studies addressing the productivity of these systems have been conducted, mainly due to the difficulty of data collection, this difficulty compounded by the fact that its implementation be very fragmented, divided into several tasks and subtasks with different efforts, and happen simultaneously at different floors. In this context, justifies the development of a comptational tool that integrates the design of building systems, with the differential use graphical interface, procedures for data collection to assess the productivity of labor in the execution of these building systems, goal this work. To achieve it, initially proceeded to the understanding of the concept of productivity and indicators for its measurement as well as the procedures for collecting data in order to measure them, understanding the parts compose the SPHSGC and the process of implementation, evaluation and choice of programming language for the development of the software and ultimately their development, with testing to verify its applicability and reliability. As contributions stand out initially using the graphical interface of the projects of building systems to o stain quantitative data regarding the performance of these services, linking this information to the man-hours defendants, in their various tasks and subtasks involved in their implementation . Besides this factor facilitator, the program offers the user, which can be the manager of services or even responsible for implementation, indicators of productivity of labor and the current stage of its implementation over the floors of the building. Finally, it is noteworthy that the current use of this tool will provide managers with a database on the productivity of labor that can be used for prediction of these values for future works, feasibility study, correct sizing of work teams, lifting costs among other benefits.
Estudo da impermeabilização, monitoramento, modelagem e simulação de cenários para a bacia do Barbado - Cuiabá/MT
(Universidade Federal de São Carlos, 2012-10-26) Faria, Nilma de Oliveira; Barbassa, Ademir Paceli; https://lattes.cnpq.br/2979012440240781; https://lattes.cnpq.br/6699717652548414
This paper aims to hydrologically simulate the Barbado Stream watershed, located in Cuiabá-MT, by using the SWMM model and evaluate the responses to its different waterproofing scenarios. The acquisition of the input data for the simulation involved monitoring rainfall and flow rate; geoprocessing techniques to estimate physical characteristics of the watershed and assist the study of its sealing, which in turn, conducted the on-site survey of permeable areas (AP) directly connected impervious areas (AIDC) and unconnected impervious areas (AInc) for a sample of lots included in the study watershed. Hydrological monitoring was carried out for the Barbado Stream s local precipitation, water level and velocity during precipitation events, which allowed the construction of a rating curve for the monitoring section up to the stage of 80 cm, extrapolated up to the stage of 2,60 m. The results of the sealing study revealed that the waterproofing mean of occupied lots in the watershed studied is of 82.40% and the percentage of waterproofing in the total area of the studied watershed is 55.07%. During calibration, a sensitivity analysis of the parameters was held, resulting as the most sensitive parameters the sealed area (AIDC) and the Manning s roughness coefficient for channels. The calibration, performed by trial and error for two events, presented a satisfactory adjustment shown by the average determination coefficient of 0.912, Nash-Sutcliff coefficient of 0.842 and 0.025% of average error between the peak flows observed and estimated by the model. The model validation was verified for two events with adjustments close to those found in calibration. The simulation of rainfall scenarios for rainfall return periods of 2 up to 100 years revealed an increase in the peak flow of 12.6% to 16.9% for Scenario 2 and an increase from 11.7% to 22.0% for Scenario 3, both compared to the current occupation of Scenario 1. Even for return periods of 2 years, floods were found in scenario 1 at one point and in scenarios 2 and 3 in three points.
Síntese de clorinas anfifílicas com potenciais aplicações em terapia fotodinâmica
(Universidade Federal de São Carlos, 2012-10-26) Santos, Fabiane Aparecida Batalha dos; Oliveira, Kleber Thiago de; https://lattes.cnpq.br/3759761373942891; https://lattes.cnpq.br/4852061346657498
The main objective of this work was to construct amphiphilic chlorins with low aggregation in a physiological environment. The synthesis and structural characterization of the target compounds were carried out, and preliminary photophysical studies have been performed to point out the best candidates for further photochemical and biological studies (PDT studies) Initially, the porphyrin precursor 2 was synthesized using accessible reagents and a simple methodology, as described in Scheme 3. Scheme 3. Synthesis of new chlorins. i) C6H5Cl/PTSA, reflux, 2h and then ii) MeOH/H2SO4 5%, rt, overnight, 72% yield (2 steps); iii) solvent/conditions (Tabela 1) and maleiimide 9; iv) solvent/conditions (Tabela 2) and maleiimide 10; v) NH2OCH2CH2OH, THF, reflux. The second part of the work involved the Diels Alder reactions between the dienophiles (9 and 10) and porphyrin 2, as shown in Scheme 3. The synthesis of the dienophiles involved initial protection with ethylene glycol (to 7) or ethylenedithiol (to 11). The ethylene glycol protected compound 7 did not provide the expected results yielding only by-products. On the other hand, the approach using ethylenedithiol as protecting group allowed the effective synthesis of maleimides 9 and 10 (Scheme 4). Scheme 4. Synthesis of maleimides. We decided to study the relative reactivity of maleimides 9 and 10 under the Diels-Alder reactions conditions with porphyrin 2, as well as establish the ideal conditions to obtain chlorins 3a/3b and 4a/4b. Our best results were obtained for chlorins 3a and 3b with 37% and 37% yield for both; for chlorins 4a and 4b the yields were 36% and 35%, respectively. Finally, the versatility of chlorins 4a and 4b, as multi-functionalizable photosensitizers, was evaluated. These compounds reacted with 2-aminoxyethanol and the oxime-type amphiphilic derivatives 5a/5b were obtained in 67% and 74% yield, respectively. The reported compounds in this dissertation were characterized by 1D and 2D NMR spectroscopy, UV-Vis spectroscopy, infrared spectroscopy and low or high resolution mass spectrometry. The structures were assigned unambiguously. Through the synthetic studies, some photophysical tests, such as singlet oxygen production measurements, were conducted in order to evaluate the potential of chlorins 3a/3b and 4a/4b for PDT studies. 1H NMR aggregation studies were also performed to demonstrate the absence of aggregation in solution at the studied concentrations (high concentrations).