Otimização de parâmetros mecânicos e microestruturais dos moldes em areia de sílica ligados quimicamente pelo processo de cura a frio em fundição de aço

Surface defects on steel parts borne costs of smelting industries due to the need of rework. Sand molds are frequently used in foundry industries and largely responsible for providing surface defects. This study aims to optimize the levels of the molding process variables to minimize the occurrence of surface defects in steel castings in silica sand molds chemically linked by cold cure process. The methodology used the experimental design with split plot, being considered in the study the resin percentage factors in the mold formulation, addition of iron oxide, type of paint, the paint application method, amount of ink layers, use of hot air along the lines and waiting time of the mold before casting. They were analyzed as response variables erosion defects, sand inclusion, penetration, porosity and surface finish. Tensile strength tests were performed to evaluate the influence of factors on mechanical parameters and the microstructural parameters were carried out the analysis of X-ray diffraction, scanning electron microscopy (SEM) and thermal analysis (TG / DSC / dilatometry). The results elucidate that for the faulty erosion, the only significant factor with a 95% confidence level was the type of ink and the ink alumina-based superior results obtained. For the sand inclusion of defect, there were three significant factors, with best results obtained with alumina-based paint and spray applied using hot air in the mold before casting the metal. For the defect penetration, there were four significant factors, the best results being achieved with 0.8% of resin and addition of iron oxide in the molding formulation, the paint being applied by brush and standby time of 24 hours before leak. For the defect porosity with a 95% confidence level, no significant factors. For the defect surface finish, the best results were achieved with the 0.8% formulation of the resin in the mold and application of the paint brush. To obtain the levels of the factors that optimize all defects simultaneously, we performed a weighted average of the results of each type of fault, concluding that the best levels of the factors were: 0.8% resin and addition of iron oxide in the formulation of the template, application of two coats of paint applied with a brush or spray, using hot air in the mold before casting and 24 hours of waiting ready the mold before casting. These levels of the optimized factors were used in an experiment to confirm that ratified the results, helping to reduce rework and consequently reducing costs of cast steel parts.

Avaliação do planejamento de prótese parcial removível em modelos recebidos por laboratórios de João Pessoa-PB

Objective: To evaluate the planning and quality of plaster models for fabricati on of removable parti al dentures received from three commercial prosthodonti c laboratories located in the city of João Pessoa, PB, Brazil, which perform the casting procedures in their facilities. Methods: Forty 40 plaster models were photographed per laboratory, totalizing 120 models. The evaluation was performed using two questi onnaires, one designed for the dental prosthesis technicians, and another applied by the investigator for the visual evaluati on of the models. Data were analyzed using the SPSS soft ware version 13.0. Results: Ninety-two (76.7%) models did not present planning. In addition, no model presented references of insertion plane or guide pins. Calculati on of the mouth preparati on index (MPI) to evaluate the distribution of the oclusal and cingulum abutments or rests showed that 86 (71.7%) models were classifi ed as poor, 23 (19.2%) models as good and only 11 (9,.2%) models as acceptable. Defects were found in 102 (85%) models. Conclusion: The prosthodontists are not preparing the mouth of their pati ents, neglecti ng the planning of removable partial dentures, and passing this responsibility to the dental prosthesis technicians. In addition, the quality of the models sent to the laboratories was unsatisfactory.

Avaliação do planejamento de prótese parcial removível em modelos recebidos por laboratórios de João Pessoa-PB

Objective: To evaluate the planning and quality of plaster models for fabricati on of removable parti al dentures received from three commercial prosthodonti c laboratories located in the city of João Pessoa, PB, Brazil, which perform the casting procedures in their facilities. Methods: Forty 40 plaster models were photographed per laboratory, totalizing 120 models. The evaluation was performed using two questi onnaires, one designed for the dental prosthesis technicians, and another applied by the investigator for the visual evaluati on of the models. Data were analyzed using the SPSS soft ware version 13.0. Results: Ninety-two (76.7%) models did not present planning. In addition, no model presented references of insertion plane or guide pins. Calculati on of the mouth preparati on index (MPI) to evaluate the distribution of the oclusal and cingulum abutments or rests showed that 86 (71.7%) models were classifi ed as poor, 23 (19.2%) models as good and only 11 (9,.2%) models as acceptable. Defects were found in 102 (85%) models. Conclusion: The prosthodontists are not preparing the mouth of their pati ents, neglecti ng the planning of removable partial dentures, and passing this responsibility to the dental prosthesis technicians. In addition, the quality of the models sent to the laboratories was unsatisfactory.

Simulação computacional de materiais bidimensionais: funcionalização de defeitos extensos no grafeno e retenção de contaminantes por argilominerais

In this work are considered two bidimensional systems, with distints chacacteristcs and applicabilitys. Is studied the adsorption of transition metals (MT) Fe, Co, Mn and Ru in extended defects, formed by graphene grain boundaries. First in pristine graphene The hollow site of carbon hexagon, in pristine graphene, are the most stable for MT adsorption. The Dirac cone in eletronic structure of graphene was manteined with the presence of MT. For the considered grain boundaries the MT has a greater stability for absorption in the grain boundaries sites in comparison with pristine graphene. Through the energy barrier values, are observed diffusion chanels for MT localized on the grain boundaries. This diffusion chanels indicate a possible formation of nanolines of MT in graphene. For the first stage of the nanolines, ate observed a better stability for the system with greater MT concentration, due to MT-MT interactions. Also, due to the magnetic moment of the MT, the nanolines show a magnetization. For the most stable configurations the system are metallics, particularly for Fe the band structure indicates an anisotropic spin current. In a second study, are considereted the retention capacity for metallic contaminants Cd and Hg in clayminerals, kaolinite (KAO) and montmorillonite (MMT). Through the adsorption energies of contaminantes in the clayminerals, was observed a increase in stability with the increase of contaminants concentration, due to the interaction Cd-Cd and Hg-Hg. Also, was observed that KAO has a strong interaction beteween monolayers than MMT. In this sence, for the adsoption process of contaminantes in the natural form of KAO and MMT, the latter has a better retention capacity, due to the small net work for contaminant intercalation. However, when the modification of clayminerals, with molecules that increase the spacing between monolayers, exist a optimal condition, which the contaminant absorption are more stable in KAO system than in MMT. In the Langmuir adsorption model for the clayminerals in the optimal monolayer spacing, the retention capacity for Cd and Hg in KAO system are 21% greater than in MMT system. Also, for the X-ray Absorption Near Edge Spectroscopy (XANES) for the K edge of Cd and Hg, are found a positive shift of absorption edge with the decreasing of monolayer spacing. This result indicates a possible way to determine the concentration of adsorbed contaminats in relation to unabsorbed ones, from the decomposition of experimental XANES in the obteined spectras.

Fatores pré-abate que influenciam na qualidade da carne de frangos griller

The consumption of a product is directly linked to its quality, and are required to comply with quality standard regulations. In chicken "griller" which comes from industrial strains, selected for best growth performance, shot with up to 35 days old and weighing 1,400kg, they have not been reported in the literature a number of quality aspects This study aimed determine the muscle transformation time in the flesh in chickens "griller" incidence of meat defects, "PSE" (pale, soft and exdudative) and "DFD" (dark, firm and dry) and their correlation between different window times slaughter (total time between beginning of the fasting and the time of slaughter) and pH curve, four different times post mortem. The base data for the study was composed of information of 208 chickens, collected between August and September 2014, in a slaughterhouse slaughtering chickens in the middle region of Triangulo Mineiro and Alto Paranaíba. We used the Minitab 17.1.0 program for the development of descriptive statistical analysis and Pareto charts. The Pearson correlation was used to evaluate the linear relationship between two variables and Excel 2013, Microsoft Office®, to produce tables and graphs. The analysis consisted of 11 chickens cities and the distance to the poultry slaughterhouse ranged from 24.5 km to 123 km. It was observed that the pH curve decays gradually until time 5horas after slaughter, and its increase was 24, indicating the transformation of the muscle meat. The incidence of regular meat was 39.9%, "DFD" 30.3% and "PSE" 29.8%. For "DFD" meat, it was observed that factors: low ambient temperature, longer transportation and fast window and mileage at dirt road, contributed to its occurrence (p <0.05). For "PSE" meat, it was observed that lower body weight factors, longer transport favored frequency (p <0.05) of the meat defect. There was no significant correlation in variance analysis between distance, waiting time at rest shed and humidity related to meat defects (p> 0.05). This high incidence of defects meat may be due to pre-slaughter stress factors.

(Table 2) Lipid fluxes derived from sediment trap samples

Phytoplankton is a sentinel of marine ecosystem change. Composed by many species with different life-history strategies, it rapidly responds to environment changes. An analysis of the abundance of 54 phytoplankton species in Galicia (NW Spain) between 1989 and 2008 to determine the main components of temporal variability in relation to climate and upwelling showed that most of this variability was stochastic, as seasonality and long term trends contributed to relatively small fractions of the series. In general, trends appeared as non linear, and species clustered in 4 groups according to the trend pattern but there was no defined pattern for diatoms, dinoflagellates or other groups. While, in general, total abundance increased, no clear trend was found for 23 species, 14 species decreased, 4 species increased during the early 1990s, and only 13 species showed a general increase through the series. In contrast, series of local environmental conditions (temperature, stratification, nutrients) and climate-related variables (atmospheric pressure indices, upwelling winds) showed a high fraction of their variability in deterministic seasonality and trends. As a result, each species responded independently to environmental and climate variability, measured by generalized additive models. Most species showed a positive relationship with nutrient concentrations but only a few showed a direct relationship with stratification and upwelling. Climate variables had only measurable effects on some species but no common response emerged. Because its adaptation to frequent disturbances, phytoplankton communities in upwelling ecosystems appear less sensitive to changes in regional climate than other communities characterized by short and well defined productive periods.

Vinculação, Estilos Educativos Parentais e Esquemas Precoces Mal Adaptativos em Reclusos

Introdução: Sobretudo estudos internacionais focam a importância da vinculação e dos estilos educativos parentais no desenvolvimento de comportamentos delinquentes e antissociais. Em Portugal, alguns estudos focados na população reclusa, analisam, separadamente, estilos educativos parentais, personalidade e esquemas precoces mal adaptativos mas, segundo sabemos, nenhum explora, simultaneamente, a vinculação, os estilos educativos parentais e os esquemas precoces mal adaptativos nesta população. São nossos objetivos caracterizar uma amostra de reclusos quanto à vinculação em diferentes relacionamentos, estilos educativos parentais e esquemas precoces mal adaptativos (EPM) e, sobretudo, explorar associações entre estas três variáveis (e destas com variáveis sociodemográficas, familiares, clínicas e relativas à pena). Metodologia: 44 reclusos do sexo masculino (M = 37,3 anos; DP = 10,98; variação = 23-67) preencheram voluntariamente um questionário sociodemográfico e os seguintes instrumentos: EMBU – Memórias de Infância, Experiências em Relações Próximas - Questionário de Estruturas Relacionais e Questionário de Esquemas de Young (QEY). Resultados: Verificou-se, quanto às associações entre vinculação e estilos educativos parentais que: menor suporte emocional paterno associou-se a maior evitamento pai, evitamento mãe e evitamento companheira; menor suporte emocional materno associou-se a maior evitamento mãe, evitamento pai, ansiedade mãe e ansiedade pai; maior rejeição paterna associou-se a maior evitamento mãe, evitamento pai, ansiedade mãe e ansiedade pai; maior rejeição materna associou-se a maior evitamento pai e evitamento mãe. No que toca às associações entre as dimensões de vinculação e EPM, é de enfatizar a associação positivas entre os EPM do domínio distanciamento e rejeição com o evitamento mãe, ansiedade mãe e ansiedade pai, particularmente, os EPM de abandono, desconfiança/abuso e isolamento social, por consistentemente se associaram às dimensões de vinculação. No domínio autonomia e desempenho deteriorados, o fracasso e a dependência/incompetência associaram-se positivamente ao evitamento mãe, a dependência/incompetência à ansiedade pai e o fracasso ao evitamento companheira. Quanto ao domínio limites deteriorados, a grandiosidade associou-se positivamente à ansiedade pai. No domínio vigilância e inibição o pessimismo/negativismo correlacionou-se positivamente com a ansiedade mãe e pai e a autopunição com a ansiedade mãe. Quanto às associações entre dimensões de estilos educativos parentais e os EPM, o domínio distanciamento e rejeição apresentou, de novo resultados relevantes: menores níveis de suporte emocional materno associaram-se a maiores níveis de privação emocional; maiores níveis de rejeição e sobreproteção materna e paterna a maiores os níveis de abandono; maiores níveis de rejeição materna e paterna a maiores níveis de desconfiança/abuso; maiores níveis de rejeição materna e sobreproteção materna e paterna a maiores níveis de isolamento social; maiores níveis de rejeição e sobreproteção paterna a maiores níveis de defeito. Enfatiza-se, também, a associação entre níveis maiores de rejeição paterna e os EPM de grandiosidade, padrões excessivos e pessimismo. Maiores níveis de rejeição materna associaram-se a maiores níveis de pessimismo e autopunição. Discussão: Embora numa amostra pequena, este estudo explorou, pela primeira vez, numa amostra de reclusos portugueses, em simultâneo, associações entre a vinculação, os estilos educativos parentais e os esquemas precoces mal adaptativos. O domínio esquemático distanciamento e rejeição parece ser o mais influenciado pela vinculação estabelecida em diferentes relacionamentos e pelos estilos educativos parentais. / Introduction: Mainly international studies focus on the importance of attachment and parental rearing styles in the development of delinquent and antisocial behaviors. In Portugal some studies focused in the inmate population analyze, separately, parental rearing styles, personality and early maladaptive schemas but, to our knowledge, none simultaneously explores attachment, parental rearing styles and early maladaptive schemas in this population. It is our objective to characterize a sample of inmates concerning attachment in different relationships, parental rearing styles and early maladaptive schemas (EMS) and, above all, explore associations between this three variables (and also with sociodemographic, family, clinic and sentence related variables). Methodology: 44 male inmates (M = 37,3 years; SD = 10,98; variation = 23-67) voluntarily filled in a sociodemographic questionnaire and the following instruments: EMBU – Childhood Memories, Experiments in Close Relationships – Structural Relationship Form and the Young Schema Questionnaires (YSQ) Results: we verified, regarding associations between attachment and parental rearing styles that: less paternal emotional support associated with higher father avoidance (in attachment), mother avoidance and partner avoidance; less maternal emotional support associated with higher mother avoidance, father avoidance, mother anxiety and father anxiety; higher paternal rejection associated with higher mother avoidance, father avoidance, mother anxiety and father anxiety; higher mother rejection associated with father avoidance and mother avoidance. Regarding associations between attachment dimensions and EMS, we emphasize positive associations between EMS in the disconnection and rejection domain with mother avoidance, mother anxiety and father anxiety, particularly, the abandonment, distrust/abuse and social isolation EMS, as they were consistently associated with the this attachment dimension. In the impaired autonomy and performance domain, the failure and dependency/incompetence EMS are positively associated with mother avoidance, the dependence/incompetence EMS to father anxiety and failure to partner avoidance. About the impaired limits domain, grandiosity EMS positively associated with father anxiety. In the overvigilance and inhibition domain, pessimist/negativism EMS positively correlated with mother and father anxiety and self-punishment EMS with mother anxiety. About the associations between parental rearing styles and the EMS, the disconnection and rejection domain presented again relevant results: lower levels of maternal emotional support associated with higher levels of emotional deprivation; higher levels of maternal and paternal rejection and overprotection associated with higher levels of abandonment; higher levels of maternal and paternal rejection associated with higher levels of distrust/abuse; higher levels of maternal rejection and maternal and paternal overprotection associated with higher levels of social isolation; higher levels of paternal rejection and overprotection associated with higher levels of defectiveness. We also emphasize the association between higher levels of paternal rejection and the grandiosity, excessive patterns and pessimism EMS. Higher levels of maternal rejection associated with higher levels of pessimism and self-punishment EMS. Discussion: Although in a small sample, this study explored, for the first time, in sample of Portuguese inmates, simultaneously, the associations between attachment, parental rearing styles and early maladaptive schemas. The schematic domain of disconnection and rejection seems to be the most influenced by the established attachment in different relationships and by parental rearing styles.