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Funcionalização de 5-iodo-1,2,3-triazóis e síntese de seleno- e tioésteres por meio de reações de acoplamento carbonilativo empregando monóxido de carbono gerado ex situ
(Universidade Federal de São Carlos, 2022-06-06) Albuquerque, Danilo Yano de; Schwab, Ricardo Samuel; https://lattes.cnpq.br/6935890756504964; https://lattes.cnpq.br/6845648360120456
The use of pressurized carbon monoxide (CO) gas cylinders can lead to serious risks during their handling. Hence, the demand for safer carbonylation methods has been gradually increasing with the use of different techniques or CO-realeasing molecules. In the first chapter, we report a simple and direct palladium-catalyzed aminocarbonylation of 5-iodo-1,2,3-triazoles backbone for the incorporation of an amide functional group by employing an alternative source of carbon monoxide generated ex situ by dehydration of formic acid in sulfuric acid (Morgan’s reaction). The reaction was performed in a two-chamber system (COware) providing the synthesis of 26 compounds with yields up to 98% by using different primary amines and 5-iodo-1,2,3-triazoles. The methodology developed exhibited a series of advantages, such as simplicity, short reaction time, high yields, the use of dimethyl carbonate as a sustainable solvent, and the use of efficient alternative source of carbon monoxide, avoiding pressurized cylinder. The chapter 2 is focused on the development of a new catalytic protocol for the synthesis of seleno- and thioesters from a palladium-catalyzed carbonylative coupling reaction between aryl iodides and nucleophilic selenium and sulfur sources, which were obtained by in situ reductive cleavage of diorganoyl dichalcogenides with the assistance of zinc metal. This approach exhibited good functional group tolerance, allowing the synthesis of 30 compounds with yields up to 97%. Interestingly, aryl iodides carrying electron-withdrawing groups showed slower reactivity than those with electron-donating counterparts, affording the products with lower yields. For these cases, it was necessary to increase the amount of carbon monoxide to improve the reaction yield. The important features of this methodology include mild reaction conditions, the use of efficient alternative source of carbon monoxide, avoiding pressurized cylinder, and avoids the use of selenols and thiols, which are difficult-to-handle, easily oxidized, and have the unpleasant odor.
Avaliação de políticas de gestão da manutenção baseadas na mitigação de riscos considerando critérios de disponibilidade e produtividade
(Universidade Federal de São Carlos, 2022-06-06) Alonso, Samanta de Lima; Silva, João Eduardo Azevedo Ramos da; https://lattes.cnpq.br/3823047207711289; https://lattes.cnpq.br/3808887493000428
Production systems were transformed by the advances of the Industrial Revolutions. In order to keep up with technological progress and achieve desired productivity levels, maintenance management has become a key factor for organizations. Since every production system is prone to failures in its equipment, directly impacting the reduction of manufacturing capacity, it is necessary to properly use maintenance policies to keep a system in good operating condition. In this sense, it is understood that the greater the availability of equipment, the greater the productivity of the system. Thus, the present work aims to incorporate risk mitigation applied together with the modeling and simulation of discrete events as tools to support decision-making for maintenance policies that lead to increased availability and manufacturing productivity. For this, an industrial system prone to machine failures and belongs to the public administration was analyzed. In the case studied, the proposed scenarios considered that the inclusion of preventive maintenance policies with a bimonthly or quarterly frequency projects both an increase in the Mean Time Between Failures of corrective maintenance and a reduction of the Mean Time to Repair of preventive maintenance due to the anticipation of administrative procedures previously planned. The workstations submitted to such proposals were Workstation A, Workstation B and Workstation E, defined according to the risk matrix resulting from the relationship between the Annual Frequency of Failures and the Impact of Machine Unavailability. In the case of productivity, there was a gain of 10.4% in parts of the simulated products and a gain of 6.2% in subsets. In the case of availability, there was a gain of 50% in availability in Workstation A, 62% in availability in Workstation B and 41% in availability in Workstation E. Therefore, this research fills a gap in the literature by applying the modeling and simulation of discrete events in a risk analysis approach associated with maintenance management. In this way, it was possible to develop a ranking of workstations priorities and types of failure to be included in preventive maintenance policy proposals, resulting in availability and productivity gains for the studied production system.
Autonomia docente na perspectiva do Currículo Paulista: limites e possibilidades
(Universidade Federal de São Carlos, 2022-06-06) Boni, Izabel Carolina Carriel; Silva, Antonio Fernando Gouvêa da; https://lattes.cnpq.br/9621931288117213; https://orcid.org/0000-0002-8915-9952; https://lattes.cnpq.br/7483326475599558
Education has been working by the same mercantile logic for years, which seeks to homogenize the students, disregarding their wishes, experiences and culture. Therefore, in this work it was questioned how autonomous educators can be in their formation, so they can deviate from this path. Likewise, this work also aimed to question the State’s role in educator’s autonomy, reflecting about how public teaching materials can contribute to decreasing teaching autonomy, since it is the State’s role to produce, provide and verify if its materials are being applied. For this reason, it was made an analysis of the Currículo Paulista, a material that is used throughout the state network of the State of São Paulo, to understand its objectives and how it intends to achieve them. For this, it was developed a documental analysis based on the qualitative research method, using three parameters based on Freire's conceptions of education: epistemological protagonism; methodological freedom and authorship of the didactic material itself. Thus, it was possible to highlight how Currículo Paulista fulfills its role of maintaining the neoliberal ideology, which has shaped the state of São Paulo for years, aiming to form people ready for the job market, already docile and resigned to social injustices.