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Copyright of Revista Organizações em Contexto is the property of Revista Organizacoes em Contexto and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Gestión Joven is the property of Asociacion Espanola de Contabilidad y Administracion de Empresas and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Agro-industrial wastes have shown adsorptive properties and therefore can be considered as a potential alternative for the removal of dissolved contaminants present in industrial effluents. The chemical composition of the absorbate`s surface allows it to stablish its capacity to retain certain ionic contaminants. This study, determinates the point of zero charge (PZC) and the isoelectric point (IEP) of two agricultural wastes, rice husks and coconut husk, with the end of establishing the distribution of charges on the surface and subsequently to evaluate their capacity for the removal dissolved anionic or cationic colorants. In order to accomplish this, the study utilized the methods of pH drift and zeta potential varying the pH interval between 2.0 and 11 and maintaining the other variables at a constant. A PZC of 5.40 and an IEP of 9.10 were obtained for the rice husk, and a PZC of 4.61 and an IEP of 9.45 for the coconut husk, indicating a distribution of predominately positive charge on the surface. Further study of this characteristic confirmed its affinity for the removal of ionic colorants. The rice husk showed a removal of 93% of the cationic colorant basic red 46 (RB46) with at a pH higher than 5.0 and a retention of 73% of the anionic red 40 colorant(R40) at pH = 2.0 on rice husks. The determination of the PZC and IEP of the adsorbents allows for the establishment of better conditions for the adsorption of ionic colorants in solution. [ABSTRACT FROM AUTHOR]

Copyright of RISTI: Iberian Journal on Information Systems & Technologies / Revista Ibérica de Sistemas e Tecnologias de Informação is the property of Associacao Iberica de Sistemas e Tecnologias de Informacao (AISTI) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Revista de Ciencias Sociales (13159518) is the property of Revista de Ciencias Sociales de la Universidad del Zulia Venezuela and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

El artículo trata la producción y la industria del aluminio. Menciona las propiedades del aluminio, incluyendo su conductividad eléctrica, resistencia a la corrosión y baja densidad. Informa que los Estados Unidos es el mayor consumidor de aluminio y que Australia es el mayor productor de bauxita. Distingue entre el aluminio primario, que se extrae de la bauxita-alúmina, y el aluminio secundario o reciclado. Afirma que Aluminum Company of America (ALCOA) es la empresa más grande de aluminio.