Caracterização microestrutural da argila expandida para aplicação como agregado em concreto estrutural leve Microstructural evaluation of expanded clay to be used as lightweight aggregate in structural concrete

A utilização da argila expandida como agregado graúdo é economicamente viável na fabricação de concretos devido à redução da massa especifica que estes agregados proporcionam, minimizando os carregamentos atuantes nas estruturas. O objetivo deste trabalho é caracterizar a microestrutura do agregado leve de argila expandida visando sua utilização na fabricação de concretos. Na caracterização física da argila expandida foram avaliadas a massa unitária, a granulometria e a absorção de água por imersão total do agregado. Na caracterização microestrutural, foram realizadas análise química, microscopia eletrônica de varredura, difração de raios X e porosimetria por intrusão de mercúrio. A argila expandida apresentou granulometria entre as britas com graduação 0 e 1, e apresentou alta absorção de água devido à elevada porosidade deste agregado. Na análise de difração de raios X evidenciou-se a presença de sílica na forma mineral de alfa-quartzo, silicato de magnésio e óxido de alumínio e magnésio.<br>The use of expanded clay as aggregate is economically feasible in the manufacturing of concrete due to the decrease in bulk density, provided by these aggregates, minimizing the total weight of the structures. The objective of this work is to characterize the microstructure of expanded clay aggregates which are used in the manufacturing of lightweight concretes. The expanded clay was evaluated concerning of the density, the granulometry and water absorption after total immersion of the aggregate. The chemical analysis, scanning electron microscopy, X-ray diffraction and mercury intrusion porosimetry were used as well. The expanded clay presented granulometry between the aggregates grades 0 and 1 and high water absorption due to the high porosity of the aggregate. The X-ray diffraction data showed the presence of alpha-quartz, magnesium silicate and magnesium aluminum oxide

Contempt: Derogating Others While Keeping Calm

While philosophers have discussed the emotion of contempt from antiquity to the present day, contempt has received less attention in psychological research. We review the defining features of contempt, both as a short-term emotion and as a more long lasting sentiment. Contempt is similar to anger in that it may occur after (repeated) social or moral transgressions, but it differs from anger in its appraisals, actions and emotivational goals. Unlike anger, contempt arises when a person’s or group’s character is appraised as bad and unresponsive to change, leading to attempts to socially exclude the target. We discuss associative, self-regulatory and social distancing functions of contempt and present a dynamic social model of contempt versus anger