56 research outputs found
Influence of different methods of treating natural açai fibre for mortar in rural construction
Received: January 20th, 2021 ; Accepted: April 15th, 2021 ; Published: May 4th, 2021 ; Correspondence: [email protected]çai is a typical Amazonian fruit that has enormous potential for use in medicines and
foods, whose consumption has been growing year after year. One of the major environmental
impacts related to Açai is the generation of agro-industrial wastes, which are disposed of in
landfills. One of the major problems related to the reuse of natural fibres in cementitious materials
is related to their durability due to the alkalinity of the matrix. Thus, the objective of this work
was to evaluate three different methodologies for surface treatment of Açai fibre, by immersion
in NaOH, KOH and Ca(OH)2 solution to mortar application in rural construction. After the
treatments, the fibres were added in a proportion of 2.5 and 5.0% in relation to the cement mass,
in addition to the reference mortar (without fibre) in the making of the prismatic specimens
(40×40×160 mm) and cured for 28 days in room temperature. Right after the curing period, the
specimens were evaluated according to the mechanical strength of flexion and compression,
workability, water absorption by capillarity and mass density in the hardened state of each
methodology. The results showed that the best treatment methodology is with NaOH solution,
with the addition of 5% Açai fibre in relation to the cement mass, producing a suitable mortar for
use in rural buildings
Waterborne Toxoplasmosis, Brazil, from Field to Gene
Water was the suspected vehicle of Toxoplasma gondii dissemination in a toxoplasmosis outbreak in Brazil. A case-control study and geographic mapping of cases were performed. T. gondii was isolated directly from the implicated water and genotyped as SAG 2 type I
Estimativa de dimensões de bulbo molhado em irrigação por gotejamento superficial aplicando modelo de superfície de resposta
Variabilidade genética em populações de pitangueira oriundas de autopolinização e polinização livre, acessada por AFLP
Fermentação e Degradabilidade Ruminal em Bovinos Alimentados com Resíduos de Mandioca e Cana-de-Açúcar ensilados com Polpa Cítrica Peletizada
Construção de um índice global de impacto para análise ambiental comparativa aplicada à adequação de empreendimentos irregulares
Caracterização anatômico-fisiológica da compatibilidade reprodutiva de ameixeira-japonesa
Impacto da remoção de plântulas sobre a estrutura da comunidade regenerante de Floresta Estacional Semidecidual
Milho com diferentes graus de moagem em combinação com polpa cítrica peletizada ou casca de soja para vacas leiteiras no terço médio da lactação
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