Layered Double Hydroxides
Mostrando 25-31 de 31 artigos, teses e dissertações.
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25. Study of aplication of Layered Double Hydroxides in removal and slow release of pesticides / Estudo da aplicação de hidróxidos duplos lamelares na remoção e liberação lenta de pesticidas
The extensive use of pesticides in modern agriculture has been contributing to an increase in environmental contamination. Layered Double Hydroxides (LDHs), or anionic clays, bear a layered structure, and a variety of anions can be intercalated between these layers through electrostatic interactions. These layered materials can be used in adsorption/sorption
Publicado em: 2006
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26. Intercalação e funcionalização da brucita com ácidos carboxílicos
Brucite (Mg(OH)2) is a structural model of several natural layered minerals as well as of synthetic layered double hydroxides (LDH). Exchange reaction studies of these compounds are well documented in the literature but surface chemical modifications, especially for brucite, are quite rare. We report the behaviour of brucite in reaction with succinic and ben
Química Nova. Publicado em: 2005-02
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27. Models for the estimation of thermodynamic properties of layered double hydroxides: application to the study of their anion exchange characteristics
Several models for the estimation of thermodynamic properties of layered double hydroxides (LDHs) are presented. The predicted thermodynamic quantities calculated by the proposed models agree with experimental thermodynamic data. A thermodynamic study of the anion exchange process on LDHs is also made using the described models. Tables for the prediction of
Química Nova. Publicado em: 2004-08
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28. Review of the synthesis of layered double hydroxides: a thermodynamic approach
The synthesis of layered double hydroxides (LDHs) by hydrothermal-LDH reconstruction and coprecipitation methods is reviewed using a thermodynamic approach. A mixture model was used for the estimation of the thermodynamics of formation of LDHs. The synthesis and solubility of LDHs are discussed in terms of standard molar Gibbs free energy change of reaction.
Química Nova. Publicado em: 2004-08
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29. Intercalation compounds involving inorganic layered structures
Two-dimensional inorganic networks can shown intracrystalline reactivity, i.e., simple ions, large species as Keggin ions, organic species, coordination compounds or organometallics can be incorporated in the interlayer region. The host-guest interaction usually causes changes in their chemical, catalytic, electronic and optical properties. The isolation of
Anais da Academia Brasileira de Ciências. Publicado em: 2000-03
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30. Comparative study of the coprecipitation methods for the preparation of Layered Double Hydroxides
A coprecipitação é o método mais frequentemente utilizado para preparar Hidróxidos Duplos Lamelares (HDLs). Duas variações deste método podem ser utilizadas, dependendo das condições adotadas quanto ao controle de pH durante a etapa de precipitação. No primeiro caso o pH não é controlado e a síntese é conduzida em pH variável, ao passo que n
Journal of the Brazilian Chemical Society. Publicado em: 2000-02
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31. Preparação, caracterização, reações de intercalação e decomposição termica de hidroxidos duplos e amelares contendo Cd, Mg e Zn
In this work we have prepared Layered Double Hydroxides (LDH) using different divalent metals, aluminium as the trivalent metal, and nitrate and carbonate as the counter anions. These LDHs are bidimensional compounds which alternate positively charged layers formed by the metal atoms and hydroxyl groups and negatively charged layers formed by the counter ani
Publicado em: 1992