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A parceria público-privada como instrumento urbanístico: o caso do município de São Paulo-SP
(Universidade Federal de São Carlos, 2014-11-27) Guilhen, Adriana Jesus; Falcoski, Luiz Antonio Nigro; https://lattes.cnpq.br/3200660670856698; https://lattes.cnpq.br/2816240560922863
The Federal Constitution constitutes instruments that emphasize the social purpose of the land, regulated by the City Statute; compounded by municipal responsibilities that sometimes have no corresponding item in tax collection, creating budgetary constraints that hamper investments. Combined technical and administrative obsolescence of the contemporary state, the public-private partnership is an important tool for urban reform with private funding, under the cloak of a distributive character. But the obstacles are many. Despite the existence of an important legal framework, it is not, in Brazil, a tradition of the private sector to invest in social works as the housing market is restricted. The success of the partnership depends on a paradigmatic shift in public policy: it will aim at social justice or continue to succumb to real estate speculation. Based on this background, the objective of this study is to analyze the public-private partnership within the bounds of the country's urban policy, to understand this instrument forseen in the City Statute through the analysis of its legal framework and with European experiences, with the empirical object of its application through urban operations in the São Paulo municipality. Methodology: exploratory, descriptive and explanatory; to deepen the theoretical and empirical knowledge about the situation of the problem and the analysis that was done with legislation and bibliography, constituting the major source of evidence. Results: During the analysis of the Brazilian urban reform, state administrative and technical obsolescence and limitations of public resources were observed, occupying a prominent position in public-private partnership in urban reform, and how it could be analyzed together with the European experience of social innovation, especially in the São Paulo municipality. Despite the social, economic, environmental and political appeals present in the partnership, the literature highlights contradictions and obstacles for its consolidation as an alternative to urban development based on social inclusion as well as to pay attention to the diversion of its purpose, as the practice has prioritized real estate capital. It is pertinent to note the importance of the private sector s participation in urban development, because despite the state mandate, due to its technical, administrative and financial constraints, the government has encountered obstacles in complying with this proposition. Conclusion: In this context, one of the challenges is to provide measurement tools to provide information for the evaluation of urban development in order to define the applicability of the public-private partnership, which may materially have an impact, directly or indirectly, negatively or positively, if used as an instrument of government or state policy. The legal framework deserves only a few adjustments to make the partnership attractive to the private sector and at the same time encourage fairness; however, it has not been enough to make the partnership viable given the complexity and contradictions of capitalist urbanization. Accordingly, it is hoped that the government and the private sector will be compelled to seek adequate ways of carrying out a public-private partnership, with management focused on the areas of social justice.
Propriedades microestruturais e magnéticas de policristais de V2O5, CoV2O6 e Co3O4 sintetizadas por método Pechini
(Universidade Federal de São Carlos, 2014-11-27) Dreifus, Driele Von; Oliveira, Adilson Jesus Aparecido de; https://lattes.cnpq.br/4640148190073166; https://lattes.cnpq.br/1847280941369286
In this work we performed an extensive research about the magnetic properties of three materials, vanadium pentoxide (V2O5), cobalt tetraoxide (Co3O4) and cobalt vanadate II (CoV2O6). All the three oxides were synthesized by a sol-gel technique named Pechini method. These oxides present remarkable distinct characteristics. The first one, V2O5, although being reported as a diamagnetic material in literature, presented a paramagnetic behavior accompanied by an antiferromagnetic transition at 80K. This behavior has its origin in structural defects in the sample such as oxygen vacancies. The presence of these structural defects in the sample was confirmed by photoluminescence measurements as a function of the temperature which showed a characteristic indirect band gap emission and another emission at lower energy, characteristic of oxygen vacancies. The second oxide, Co3O4, presented the usual antiferromagnetic transition at about 32K, and an additional peak characterized as a metastable transition at a lower temperature. This behavior was observed in the AC susceptibility measurements that the position of this peak exhibits a variation as the drive frequency is changed. This metastable transition might has it origin in the presence of particles with different sizes in the sample. This can provide changes to grains surface condition giving rise to canted moments which can contribute to frustrations in the system, in addition to generating an increase in the magnetization for temperatures below this transition. The third oxide studied in this work is CoV2O6. This material has very peculiar magnetic properties like plateaus in its magnetization curve which are induced by the applied magnetic field. At temperatures below 7K, the system changes from an anisotropic antiferromagnetic state to a ferrimagnetic state, with a saturation tendency with the magnetic field increase. The interactions between the quasi one-dimensional chains of cobalt in this, that comprises the material, lead to frustrations in the system structure that allow the emergence of various transitions. We also observed in this system a transition at about 2,8K, with low intensity when compared to that one at 7K. This transition has an intensity dependence with AC drive frequency observed in AC susceptibility measurements as a function of temperature.