Chrysotile
Mostrando 1-12 de 127 artigos, teses e dissertações.
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1. Serpentinites: Mineral Structure, Properties and Technological Applications
Serpentine is a versatile mineral family rich in Mg silicate with several polymorphic phases, mainly antigorite and lizardite, all of them with similar chemical composition (Mg3Si2O5(OH)4). Their structures are generally composed of octahedral layers rich in Mg[MgO2(OH)4]6- , attached to a tetrahedral silicate [Si2O5]2- sheet. The unique physicochemical prop
J. Braz. Chem. Soc.. Publicado em: 2020-01
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2. Potential Slow Release Fertilizers and Acid Soil Conditioners Obtained by One-Pot Mechanochemical Activation of Chrysotile:Cement Roofing Sheets with K2HPO4
Chrysotile:cement roofing sheets were milled with and without K2HPO4. As indicated by X-ray diffraction (XRD), the samples crystallinities were reduced with the increasing milling time. The same tendency was observed by scanning electron microscopy (SEM) and transmission electron microscopy (TEM), with disaggregation of the chrysotile fiber bundles and forma
J. Braz. Chem. Soc.. Publicado em: 2019-02
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3. Interação da crisotila com células de carcinoma de pulmão humano em cultura: interferência com a mitose utilizando genes repórteres e microscopia em tempo real e estudo do potencial genotóxico / Chrysotile interaction with human lung carcinoma cell culture: interference on mitosis using report genes and real time microscopy and the study of genotoxic potential
Asbesto é um nome geral dado a seis tipos de fibras minerais encontradas naturalmente na crosta terrestre. Estas fibras vêm sendo exploradas industrialmente desde 1970, porém diversos trabalhadores expostos às fibras apresentaram patologias no trato respiratório, como fibroses e carcinomas. Alguns tipos de fibra foram banidos do mercado, porém o tipo d
Publicado em: 2010
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4. Nanocomposites: synthesis, structure, properties and new application opportunities
Nanocomposites, a high performance material exhibit unusual property combinations and unique design possibilities. With an estimated annual growth rate of about 25% and fastest demand to be in engineering plastics and elastomers, their potential is so striking that they are useful in several areas ranging from packaging to biomedical applications. In this un
Materials Research. Publicado em: 2009-03
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5. Heterocoagulation of chrysotile with polytyrene latex / Heterocoagulação entre crisotila e latex de poliestireno
Chrysotile is a magnesium silicate with fibrous habit and ideal formula Mg6Si4O10(OH)8, having 1:1 layered structure of tetrahedral tridimite (silicate) with octahedral brucite (magnesium hydroxide). The layers are curved and rolled, resulting in cylindrical fibrils with brucite in the external surface and tridimite in the hollow internal surface. The fibril
Publicado em: 2007
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6. Catalytic activity in oxidation reactions of anionic iron(III) porphyrins immobilized on raw and grafted chrysotile
Crisotila natural e quimicamente modificada foi usada como matrizes para imobilização de ferroporfirinas de segunda geração. As atividades catalíticas dos sólidos obtidos foram avaliadas em reações de oxidação de cicloexano, usando iodosilbenzeno como oxidante. Os resultados de catálise foram analisados e comparados aos obtidos pela imobilização
Journal of the Brazilian Chemical Society. Publicado em: 2006-12
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7. Dissolução da crisotila brasileira na presença de dodecilsulfato de sodio e dipalmitoilfosfatidilcolina
The use of chrysotile has decreased markedly because of health risks in the lungs associated with its inhalation. Inhaled particles become coated by extracellular lung fluid, which is mainly dipalmitoylphosphatidylcholine (DPPC). It is known that Brazilian chrysotile is rapidly removed from the lungs, but quantitative studies about DPPC or any other surfacta
Publicado em: 2006
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8. Resposta comparativa pleural "in vivo" e do mesotélio "in vitro" à exposição por diferentes fibras de asbesto / Comparison of in vivo pleural response and in vitro mesothelial response to different asbestos fibers
Asbestos-derived products are used thoroughly by industry. Several diseases related to asbestos exposition have been described, among them the primary tumor of the pleura mesothelioma. The mechanisms by which asbestos fibers produce injury to the pleural space are not clear. Among the factors possibly implicated are the effects secondary to an inflammatory r
Publicado em: 2006
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9. Síntese de ésteres derivados de carboidratos com propriedades surfactantes utilizando lipases imobilizadas em suporte sólido
Sugar esters constitute one of the main kinds of natural surfactants. These called biosurfactants show different advantages related to the synthetic surfactants. They are easily degraded in the ground and water with low toxicity what allows their industrial use in pharmaceutical food and cosmetic products. A particular strategy about these compounds is that
Publicado em: 2006
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10. Influence of glucan on the adhesion between chrysotile and solids / Influencia da glucana na adesão entre crisotila e solidos
Estudos prévios de adesão de Saccharomyces sp. e crisotila mostraram enovelamento não usual das células pelas fibrilas de crisotila. O mecanismo proposto para este fenômeno baseou-se nas interações de van der Waals entre as fibrilas e os polissacarídeos da parede celular, interações estas dependentes do tamanho e da geometria das fibrilas e das cé
Publicado em: 2004
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11. Ethanol fermentation of a diluted molasses medium by Saccharomyces cerevisiae immobilized on chrysotile
Crisotila é um mineral constituído de silicato de magnésio de hábito fibroso abundante no Brasil e pode ser usada como suporte mineral para células de levedura em fermentação alcoólica com células imobilizadas. Neste trabalho foi investigada a função catalítica da presença de crisotila em fermentações alcoólicas com células de Saccharomyces
Brazilian Archives of Biology and Technology. Publicado em: 2003-12
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12. Evaluation of the catalytic activity of lipases immobilized on chrysotile for esterification
Neste trabalho foi estudada a síntese de ésteres catalisada por lipases imobilizadas em crisotila (asbesto), em meio orgânico. Lipases de diferentes fontes (Mucor javanicus, Pseudomonas cepacia, Rhizopus oryzae, Aspergillus niger e Candida rugosa) foram imobilizadas em crisotila, um silicato magnesiano de baixo custo, e utilizadas na esterificação dos �
Anais da Academia Brasileira de Ciências. Publicado em: 2003-06