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Preparação, caracterização e otimização de biocompósitos poliméricos comestíveis reforçados com fibras vegetais
(Universidade Federal de São Carlos, 2017-05-19) Otoni, Caio Gomide; Aouada, Márcia Regina de Moura; https://lattes.cnpq.br/2870655742911951; Mattoso, Luiz Henrique Capparelli; https://lattes.cnpq.br/5839043594908917; https://lattes.cnpq.br/9403804691367376
The ever-growing environmental concern arising from the unrestricted exploitation of fossil raw materials for the massive production of non-biodegradable materials, guided by the rapid increase in the world population as well as in the demand for foodstuffs, encourages research on alternative materials from renewable sources. Herein, edible biocomposites based on peach puree or carrot processing waste (CPW) were produced. Hydroxypropyl methylcellulose (HPMC) and cellulose fibers were added to play ligand and mechanical reinforcement roles, respectively. Previously, the film-forming components were comprehensively studied separately. The effects of HPMC chemical structure were investigated in order to choose a grade – Methocel® E4M – that leads to suitable physical-mechanical performance. Cellulose fibers were miniaturized by high-pressure microfluidization and its dispersion within the HPMC matrix was optimized through a central composite design (CCD). Seven microfluidization cicles were found to be ideal for the mechanical reinforcement of the matrix. Once the behaviors of miniaturized cellulose fibers, peach puree, and CPW in the HPMC matrix were elucidated, ternary mixture designs were carried out to set up correlations among biocomposites’ formulations and their mechanical properties. Optimized formulations were used to produce (i) biodegradable biocomposites featuring suitable physical-mechanical properties for packaging applications – using CPW, HPMC, and cellulose fibers – and (ii) edible bioplastics having unique sensory and nutritional characteristics by means of combining peach puree and HPMC. Finally, the production protocols of both materials were successfully scaled-up towards a pilot scale through a continuous casting approach, being the influence of the processing protocols on materials’ properties investigated.
Análise do uso do pensamento estatístico e de técnicas estatísticas em empresas industriais do Estado de São Paulo
(Universidade Federal de São Carlos, 2017-05-19) Santos, Heitor Alves dos; Toledo, José Carlos de; https://lattes.cnpq.br/9421627326330417; https://lattes.cnpq.br/3300398608680709
In order to reduce variability and improve the performance of production systems, companies seek to apply improvement programs such as Lean Manufacturing (LM), Total Quality Management (TQM), Six Sigma (SS) , Lean Six Sigma (LSS) and TPM (Total Productive Maintenance), among others. According to Makrymichalos et al. (2005) it is necessary to verify the theoretical foundations that underlie these programs in order to be used more efficiently and consequently the companies achieve acceptable results. To that end, these programs at different levels are based on Statistical Thinking (ST) and Statistical Techniques (STech). This dissertation presents the results of a research survey, with 243 industrial companies from the Sao Paulo State, with the objective of analyzing the level of presence of ST and STech in the improvement programs and the perceived results with their use. A group called "Advanced Companies" representing 16.9% of the sample, was identified in the statistical analysis, the companies in this group are the most grounded in the use of ST and STech. In addition, 29.26% of them were able to obtain perceived operational results, 26.82% obtained subjective benefits perceived with the application of ST and STech principles and 17.07% obtained both perceived operational results and subjective benefits with the use of ST and STech. The companies in this group obtained these results mainly due to the use of SS and LSS for more than 5 years. These programs incorporate the ST principles more intensively and use the basic, intermediate and especially advanced STechs.
Ferramentas quimiométricas aplicadas na avaliação de estratégias que visam a remoção de íons fluoreto em efluente de drenagem ácida de mina
(Universidade Federal de São Carlos, 2017-05-19) Rodrigues, Fabio William; Pereira Filho, Edenir Rodrigues; https://lattes.cnpq.br/3394181280355442; https://lattes.cnpq.br/8761227302227960
The goal of this study is to provide improvements in the treatment of effluents from acid rock drainage (ARD) of the Mineral Treatment Unit (Caldas / MG) of the Nuclear Industries of Brazil (INB). Due to the presence of fluoride ions in the effluent, the costs of inputs and waste management are in the order of millions of reais per year. Thus, the search for alternative solutions or an optimized condition is of paramount importance, making the current treatment system more efficient from a financial, environmental and social point of view. Of the nine materials initially tested for fluoride removal, five were selected because of the best performance: gypsum, manganese dioxide, alumina, aluminum sulfate and aluminum polychloride. Following, a selection of variables that influence the removal of fluoride was done considering: Dosage of Hydrated Lime; Stage of Addition; Time and Material Dosage, by means of fractional factorial design for each material (5 x 23-1 ). Then, with the variables and materials selected, the work was directed to obtain a response surface that allowed identifying the optimum working region, considering the responses: final fluoride concentration, costs and mass generation of solids. For this, Doehlert type design was used with three variables (13 experiments + 3 replicates) and the evaluated responses were transformed, according to criteria, through desirability function. After obtaining the response surfaces and after the models validation for the best performance materials: gypsum and hydrated lime, the efficiency of the use of gypsum - solid effluent from the treatment of ARD - was tested on continuous scale by a pilot plant operation. It was concluded that the addition of gypsum in two different points in the treatment reached the objective of fluoride concentration (less than 10.0 mg / L) with lower cost of inputs. The proposal allows cost reduction in the order of hundreds of thousands of reais per year.
Dinâmica do uso da terra e naturalidade do entorno da Floresta Nacional de Irati
(Universidade Federal de São Carlos, 2017-05-19) Almeida, Dayana; Bogaert, Jan; Santos, José Eduardo dos; https://lattes.cnpq.br/8533387365058570; https://lattes.cnpq.br/8099346855929913
Protected areas are an important strategy for the maintenance of biodiversity. However, land use dynamics of the protected areas buffer zones receive little attention in literature. The goal of this research was to identify the landscape constraints and modelers in order to maintain the naturalness of the scenarios surrounding Irati National Forest, based on the temporal and spatial dynamics of the land use and cover analysis and the Distance to Nature Index (D2N) application for the period from 1986 to 2016. The land use and cover dynamics for the study area was obtained by on-screen digitizing of LandSat-5 and LandSat-8 imagery for 1986, 1997, 2011, and 2016 in ArcGis 10.2 software, using the hemeroby scale. A trajectorie analises between the years 1986-1997, 1997-2011, 2011-2016, 1986-2016, and 1986-2016 were used to evaluate the landscape dynamics. The D2N index was applied to measure the anthropogenic impact on biodiversity based on the dynamics of land use and cover of the study area for the four years. To test the null hypothesis of the D2N index between 1986, 1997, 2011, and 2016, a multivariate permutation analysis with Euclidean distance was performed. There was an increase of the anthropisation in the surrounding Irati National Forest. However, the region still presents an expressive degree of naturalness, mainly when compared to others surrounding protected areas. The changes in the landscape presented a different dynamic regarding the different agricultural production systems in the study area. In this way, as the maintenance practices of Irati National Forest natural condition and its surroundings will also present different profiles of each production system. The statistical analysis of the D2N results shows that only 1997 presented a statistically significant difference. The results demonstrate that D2N can be an effective tool for monitoring and planning to identify a natural condition and areas with greater anthropogenic influence, proposing scenarios for biodiversity conservation.