Análise de liberação de gás e queda do Índice de plasticidade de uma massa refratária moldável

During the vertiginous growth of the monolithic moldable refractories market in the past decades, the use of Al2O3–SiO2–SiC–C refractories has been highlighted in blast furnace casting systems. Within this classification, the Ramming Mix, a monolithic mass that has the main function of making small repairs in foundry spine sticks, is manufactured by SAINT-GOBAIN Performance Ceramics Refractories and presented quality deviations due to gas release and abrupt drop in the Plasticity Index of the material in a short period of time. The study aimed to investigate the possible causes of quality deviations in the Ramming Mix mass and list potential solutions to the problem. The total amount of magnesium oxide in the mass is listed as a possible cause of the deviation due to its high reactivity with water and in the workability of the mass. Thus, the plasticity and humidity parameters of approved and disapproved masses were analyzed and the results were compared with the manual addition of different amounts of MgO in an approved mass. It is possible to verify that the higher the addition of oxide, the lower the Plasticity Index of the mass, and, in relation to humidity, there were no significant variations of the parameter with the addition of MgO. As a solution to the problem, it is proposed that the parameters specification of quality ad being changed.Trabalho de Conclusão de Curso (Graduação)A partir do vertiginoso crescimento do mercado de refratários moldáveis monolíticos nas últimas décadas, o uso de refratários da classificação Al2O3–SiO2–SiC–C vêm se destacando em sistemas de ferro gusa em alto fornos. Dentro dessa classificação, a massa de socar, uma massa monolítica que possui a principal função de fazer pequenos reparos em canais de corrida, é fabricada pela SAINT-GOBAIN Performance Ceramics Refractories e apresentou desvios de qualidade dentro de seu sistema de produção pela liberação de gás e queda abrupta do Índice de Plasticidade do material em um curto período de tempo. O estudo teve o objetivo investigar possíveis causas dos desvios de qualidade da massa de socar e elencar potenciais soluções ao problema. O óxido de magnésio em alta quantidade foi elencado como possível ocasionador do desvio devido sua alta reatividade em água e impacto na trabalhabilidade da massa. Assim, analisou-se os parâmetros de plasticidade e umidade de massas aprovadas e reprovadas e, posteriormente, comparou-se os resultados perante a adição manual de diferentes quantidades de MgO em uma massa aprovada. Foi possível constatar que quanto maior a adição do óxido, menor é o Índice de Plasticidade da massa e, perante à umidade, não houve variações significativas do parâmetro com a adição de MgO. Como solução para o problema, foi proposto que a especificação dos parâmetros de qualidade fosse alterada

NEOTROPICAL CARNIVORES: a data set on carnivore distribution in the Neotropics

Mammalian carnivores are considered a key group in maintaining ecological health and can indicate potential ecological integrity in landscapes where they occur. Carnivores also hold high conservation value and their habitat requirements can guide management and conservation plans. The order Carnivora has 84 species from 8 families in the Neotropical region: Canidae; Felidae; Mephitidae; Mustelidae; Otariidae; Phocidae; Procyonidae; and Ursidae. Herein, we include published and unpublished data on native terrestrial Neotropical carnivores (Canidae; Felidae; Mephitidae; Mustelidae; Procyonidae; and Ursidae). NEOTROPICAL CARNIVORES is a publicly available data set that includes 99,605 data entries from 35,511 unique georeferenced coordinates. Detection/non-detection and quantitative data were obtained from 1818 to 2018 by researchers, governmental agencies, non-governmental organizations, and private consultants. Data were collected using several methods including camera trapping, museum collections, roadkill, line transect, and opportunistic records. Literature (peer-reviewed and grey literature) from Portuguese, Spanish and English were incorporated in this compilation. Most of the data set consists of detection data entries (n = 79,343; 79.7%) but also includes non-detection data (n = 20,262; 20.3%). Of those, 43.3% also include count data (n = 43,151). The information available in NEOTROPICAL CARNIVORES will contribute to macroecological, ecological, and conservation questions in multiple spatio-temporal perspectives. As carnivores play key roles in trophic interactions, a better understanding of their distribution and habitat requirements are essential to establish conservation management plans and safeguard the future ecological health of Neotropical ecosystems. Our data paper, combined with other large-scale data sets, has great potential to clarify species distribution and related ecological processes within the Neotropics. There are no copyright restrictions and no restriction for using data from this data paper, as long as the data paper is cited as the source of the information used. We also request that users inform us of how they intend to use the data