Results 71 to 80 of about 68,683 (261)
Este trabalho tem por objetivo apresentar o processo recente de avanço da silvicultura do eucalipto na fronteira agrícola da Amazônia Legal maranhense. Considera-se a reprodução de modelos históricos de apropriação e mercantilização da área por grandes ...
Allison Bezerra Oliveira
semanticscholar +1 more source
A partir da decada de 80 com a Comissao de Brundtland, o Desenvolvimento Sustentavel comecou a ser fervorosamente discutido nas mais diversas reunioes entre as nacoes e mais tarde em eventos corporativos.
Mirella De Paola Padovani +1 more
semanticscholar +1 more source
Acid Sulfate Soils and Their Impact on Surface Water Quality: A Case Study in Southeast Brazil
ABSTRACT Re‐flooding of previously drained and oxidised acid sulfate soils (ASSs) can stimulate reduction processes while decreasing soil acidity, thereby mitigating the harmful effects of acidity. The aim of this study is to explore the pedogenesis of ASSs in a tropical climate and to assess the impact of ASS on surface water quality at the end of the
Francis Henrique Tenório Firmino +5 more
wiley +1 more source
NANOCRISTAIS DE CELULOSE A PARTIR DE CELULOSE BACTERIANA
Bacterial cellulose produced from Gluconacetobacter xilinus was used to produce cellulose nanocrystals by sulfuric acid hydrolysis. Hydrolysis was performed with 64% sulfuric acid at 50 ºC with the hydrolysis time ranging between 5 and 90 min. The production of nanocrystals was observed to have size distributions that were dependent on hydrolysis times
Lima, Lais R. +7 more
openaire +3 more sources
PROSPECÇÃO TECNOLÓGICA SOBRE AS COMPOSIÇÕES DE DERIVADOS DE CELULOSE E CELULOSE NA ÁREA MEDICINAL
Nos últimos anos há grande interesse mundial em novas tecnologias que possibilitem a utilização de produtos com menor impacto ambiental. Composições de derivados de celulose e celulose têm gerado materiais para a área medicinal, entre outras. Este trabalho consiste no monitoramento tecnológico das composições de derivados de celulose e celulose na ...
Junior, Luis Carlos de Souza Ferreira +2 more
openaire +2 more sources
ABSTRACT Acid sulfate soils (ASS) with sulfide minerals (i.e., contain sulfidic materials) are widely distributed in both coastal and inland regions, and if exposed to air, the oxidation of sulfide minerals results in the production of sulfuric acid with the formation of thionic horizons (pH < 4) along with profound mineralogical changes.
Francis Henrique Tenório Firmino +3 more
wiley +1 more source
A cirurgia ortopedica maxilofacial tem como um de seus maiores desafios a reparacao ossea efetiva, principalmente em casos de perdas teciduais extensas por diversas causas.
P. Vaz, Rudolf Huebner, H. Costa
semanticscholar +1 more source
ABSTRACT The use of sequential extraction methods is a common practice for analysing the availability of potentially toxic elements in soils and sediments. However, the simultaneous presence of oxidisable and reducible minerals in acid sulfate soils with a thionic horizon raises questions about the accuracy of these methods.
Francis Henrique Tenório Firmino +5 more
wiley +1 more source
The objective of this study was to evaluate the effects of supplementation with different sources of energy and nitrogenous compounds on the in vitro growth and production of bacteriocin of lactic acid bacteria.
Isabela Pena Carvalho de Carvalho +6 more
doaj +1 more source
A celulose, polissacarideo de origem vegetal, e um biopolimero abundante encontrado na natureza e, portanto, de grande valia para a ciencia dos materiais em aplicacoes na area medica, cosmetica, refinaria e outros. Como alternativa a producao tradicional
Grazielly Maria Didier de Vasconcelos +4 more
semanticscholar +1 more source

