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Tenacificação de poli(ftalamida) (PPA) através de nanocompósitos com carbonato de cálcio e de blendas com copolímero estireno/etileno-butileno/estireno (SEBS)
(Universidade Federal de São Carlos, 2010-05-20) Custódio, Gustavo José Saad; Pessan, Luiz Antonio; https://lattes.cnpq.br/8276650236213537; https://lattes.cnpq.br/0815560053137329
This project aims the toughening of a high performance thermoplastic polyphthalamide (PPA). PPA resins is a good choice for special applications where the conditions are more severe than the ones an engineering thermoplastic can handle. In this study it was prepared two different types of PPA composites through the mixture of PPA and the elastomeric component and the nanoparticles of the mineral filler. The thermoplastic elastomer that was used is the block copolymer SEBS (styrene- ethylene/butylene-styrene), grafted with maleic anhydride and the mineral filler to be used is the nanosized calcium carbonate filler surface treated with stearic acid. The main emphasis of the study is to study the effects of incorporation of organic and inorganic additives in the toughening mechanisms, in the mechanical properties (especially impact strength) and in the structure of the PPA matrix and relationship between them. The mixture of the seventeen composition was done into a twin screw extruder. The inorganic nanoparticles of calcium carbonate did not alter significantly the properties of impact resistance, while the incorporation of SEBS obtained an increase up to ten times compared to pure PPA. However, the presence of rubber phase resulted in reduced stiffness of the system, which did not occurred in the nanocomposites, where such property has increased in value. Calcium carbonate in this system did not act as nucleating agent, and its incorporation decreased both the crystallization temperature as the degree of crystallinity. The presence of SEBS-g-MA in the blend PPA / SEBS promoted a decrease in particle size, which resulted in better mechanical properties.
Arranjo produtivo local e apicultura como estratégias para o desenvolvimento do sudoeste de Mato Grosso
(Universidade Federal de São Carlos, 2010-05-20) Amaral, Anderson Marques do; Margarido, Luiz Antonio Correia; https://lattes.cnpq.br/5685663057214334; https://lattes.cnpq.br/4051957230381923
This study aims to characterize the honey production and the local productive honey arrangement, through the evaluation of the land use, honey production, regional flora and product quality. It also aims to stimulate local process of development, rural protagonist and social inclusion of the agricultural workers from the southeast of Mato Grosso. We have evaluated the production of honey during the period of 1987 to 2007, of the towns engaged in APL of apiculture which is available on the SIDRA System by IBGE. The quantification of the use and the topsoil of the soil were obtained through satellite images. We have used SPRING and ArcGIS software for the date using field information and appropriate terminology. We have identified the most important vegetal species for the production of honey. We have determined ten physic-chemistry parameters and we have evaluated the characteristics of the labeling of the commercialized honey. The town of Cáceres (42%) presents the biggest honey production fallowed by the towns of Comodoro (11%), then Poconé (7%), then Reserva do Cabaçal (7%), then Conquista do Oeste (6%), and Porto Espiridião (6%). The production of honey is not the principal economic activity of the apiculture of this region. Most of them have just one apiary with a small number of beehives and they lack time of experience on this activity. The extraction and benefit of honey is done in manufactured fashion and the commercialization of their honey is done directly to the consumers, in the local retailer market. The level of technology implemented in this activity is low and the farmers have also a low level of professionalization. Natural Vegetation was the predominant class of the use of the soil on the majority of the apiaries. The kinds of vegetal covering were summarized as it follows: Savannas; Ecological Tension; Seasonal Forest; Riparian Formation. Grazing was the only kind of entropic agriculture use. Not Agriculture Entropic Areas were less representative. The classes of the use of soil and the different kinds of vegetal covering printed differences in the richness of plants and in the production of honey of the apiaries. The evaluation of the use of the soil and the vegetal covering of it around the apiaries allows the establishment of the appropriate management and the ways of sustainable uses of the natural resources. The results of physic-chemistry analysis for the samples of honey showed that the median for humidity, redactor and non redactor sugars were among the required patterns by the MAPA. The percentage of insolates solids and the fixed mineral residuals remained over. The Fiehe reaction indicated the presence HMF in others samples. All of the brands evaluated presented some parameters over the maximum limit allowed by the Brazilian legislation, pointing out production problems, as well as collecting and processing of honey. Only two kinds of honey available in the local market, from Cáceres and some other regions, have the sanitary inspection validity. The labeling of the majority of the trades are not in conformity with nowadays legislation, and it ignores the important instrument of identification of origins of honey, which is a guarantee of products with quality and security to the customer. The apiaries represent a way of sustainable use of preserved natural vegetation areas, degradation grazing areas and existing capoeiras, besides, this activity shows itself compatible with some others activities already consolidated in the region of southeast of Mato Grosso.