The conformation of a ceramic piece follows the steps of preparing the raw material, molding, lamination, drying, and firing. Drying is a thermodynamic process of heat and mass transfer, with dimensional variations of the product that requires a large amount of energy. Ceramic materials when exposed to non-uniform drying may suffer cracks and deformations, reducing their post-drying quality. Thus, this work aimed to study the drying of industrial ceramic blocks in an oven with forced air circulation. Experiments were carried out to characterize the clay and drying of the ceramic block at temperatures ranging from 50 °C to 100 °C. Results of the chemical, mineralogical, granulometric, differential thermal, and thermogravimetric analysis of the clay, and heating kinetics, mass loss, and dimensional variation of the industrial ceramic block are presented and analyzed in detail. It was found that the clay is basically composed of silica and alumina (≈ 80.96%), with an average particle diameter of 13.36 μm. The study proved that drying at high temperature and low relative humidity of the air generates high rates of mass loss, heating, and volumetric shrinkage in the ceramic product, and high thermo-hydraulic stresses, which cause the appearance and propagation of cracks, gaps, and cleavages, compromising the final quality of the product.

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ResumoVisando contribuir para a conservação e o preenchimento da lacuna acerca do conhecimento ecológico das plantas vasculares sem sementes no Brasil, apresenta-se resultado da análise da fenologia e sobrevivência de três populações de samambaias (Acrostichum danaeifolium Langsd. & Fisch., Lygodium volubile Sw. e Thelypteris serrata (Cav.) Alston) ocorrentes em remanescente de Floresta Atlântica no estado da Paraíba durante os períodos seco e chuvoso. Para tanto, dez indivíduos de cada população foram marcados e acompanhados em campo durante 12 meses, registrando dados fenológicos e de herbivoria, relacionando-os com dados climatológicos dos períodos.

We analyzed floristic variations in fern's metacommunity at the local scale and their relationship with abiotic factors in an Atlantic Forest remnant of northeastern Brazil. Floristic and environmental variations were accessed on ten plots of 10 × 20 m. We performed cluster analyses, based on Bray-Curtis dissimilarity index to establish the floristic relationship. The influence of abiotic factors: luminosity, temperature, relative air humidity and relative soil moisture was evaluated from a redundancy analysis. We found 24 species belonging to 20 genera and 12 families. The fern's flora showed high floristic heterogeneity (>75% for most of the plot's associations). The fern's metacommunity was structured along an abiotic gradient modulated by temperature, luminosity, and relative soil moisture.

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Bananas are some of the most consumed fruits throughout the world, providing metabolizable calories and vitamins for humans, along with many other benefits. However, this fruit tends to be easily degraded by microorganisms and other chemical agents because of the high moisture content. Considering the importance, this work focuses on an experimental study regarding banana fruit drying. For such purpose, whole bananas were hand-peeled and sliced longitudinally and then dried by a hot air circulation oven with air temperatures of 40 °C, 50 °C, 60 °C and 70 °C. Measurements of mass, temperature, and dimensions of the sample were done during the drying process. Results of drying, heating, and shrinkage (volume and surface area) kinetics are presented and analyzed. The study revealed that the drying air temperature significantly affected moisture removal, heating, and dimensions’ variation rates, as well as quality of banana fruit. The drying carried out with higher temperature and lower relative humidity of the air gave rise to higher rates of drying, heating and variation of dimensions, and shorter drying time of the product.

ResumoA deficiência hídrica em ambientes sazonalmente secos, como as Florestas Semideciduais, parece ser o principal fator que determina a seleção de espécies com mecanismos adaptativos a esse tipo de estresse, influenciando o estabelecimento, a periodicidade de crescimento, a dormência e a fenologia das plantas. Este trabalho teve como objetivo determinar a fenologia de três espécies de samambaias em fragmento de Floresta Atlântica Semidecídua no estado de Pernambuco, Brasil. Foram realizadas excursões mensais, durante 12 meses, para monitoramento de populações das três espécies. A partir da estação chuvosa, foram marcados 32 indivíduos de Adiantum petiolatum Desv., 30 de A. deflectens Mart. e 13 de A. pulverulentum L. Os dados fenológicos foram relacionados com os dados climatológicos do período de estudo. As populações apresentaram produção foliar irregular e baixa, em ambos períodos (seco e chuvoso), tendo ocorrido correlação positiva com a umidade relativa do ar e com a pluviosidade em A. deflectens e A. petiolatum. Foi observada uma constância de frondes senescentes nas três populações, variável que se correlacionou de modo inversamente proporcional com a pluviosidade e com a umidade relativa do ar apenas em Adiantum deflectens. A presença de frondes férteis foi contínua nas três populações, entretanto, em Adiantum petiolatum, esta fenofase correlacionou-se positivamente com a temperatura e a umidade relativa do ar. Os resultados indicam a existência de uma influência distinta do clima sobre as três espécies estudadas.Palavras-chave: autoecologia, fertilidade, produção foliar, variáveis climáticas, samambaias, senescência foliar. AbstractWater deficit in seasonally dry environments, such as semi deciduous forests, appears to be the main determinant of the selection of species with mechanisms that allow adaptive responses to this type of stress. Thus the availability of water influences the establishment of plants in an area and their growth and dormancy periods. The present study aimed to identify dry-and rainy-season survival strategies developed by three species of ferns occurring in a semi deciduous forest located at Aliança (Pernambuco, Brazil). Field observations were carried out to monitor the development of populations of the three species. Thirty-two individuals of Adiantum petiolatum Desv., 30 of A. deflectens Mart. and 13 of A. pulverulentum L. were studied. The phenological data were correlated to climatological data of the study period. The populations showed low and irregular frond production, occurring in both dry and rainy seasons, exhibiting positive correlation with relative humidity and rainfall to A. deflectens e A. petiolatum. Constancy in production of senescent fronds