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Entre consumo y consumidor, entre el qué y el quien, se configuran las socialidades que campan por la metrópoli empresa. Por más que el consumo tenga al consumidor como objetivo, el consumidor descifra o traduce el consumo, ya que interpone al acceso a los bienes de consumo modalidades de uso marcadas por una subjetividad no desligada de la materialidad que condiciona las relaciones sociales imperativas en los territorios urbanos. Es por ello que se apunta la necesidad de emplazar el análisis más que en unas tipologías basadas en las pautas o hábitos de consumo en una lectura atenta de las prácticas de consumo, pues no hay que olvidar que «el consumidor» no es sino un plural de consumidores, los cuales ni disponen de las mismas cuotas de solvencia ni comparten siquiera los mismos valores. Asimismo, la ciudad hipermercado, como escenario del conflicto social, es un lugar abierto a apropiaciones materiales y simbólicas alteractivas de los bienes y de los espacios de consumo. Es por ello que proponiendo una geografía social del consumo se anota que no todas las maneras de ser y estar en la ciudad se consuman en la figura del consumidor ni se consuman en el consumo. [fr] Entre la consonunation et le consommateur, entre le quoi et le qui, les socialites se conforment dans la métropole-entreprise. Malgré la consommation aie le consommateur comme objectif, le consommateur dexifre ou traduise la consommation, étant donné que il interpose des modalités d'usage aux biens de consommation. Ces modalités sont définies par une subjectivité relié à la matérialité qui conditione des relations sociales imperatives dans les territoires urbains. On place l'analyse dans les practiques de consommation plutôt que dans les typologies des habitudes de consommation. On doit pas oublier que «le consommateur» est une pluralité de consommateurs, qui n'ont pas la même solvabilité, et ils n'ont pas même des valeurs pareils. La ville-hipermarché, comme scène de la conflictivité sociales, est un lieu ouvert aux apropiations matérielles et simboliques alteractives des biens et des espaces de consommation. On propose, finalement, une géographie sociale de la consommation qui considère toutes les façons d'être dans la ville et pas seulement celles qui sont définies par la consommation.

Currently, acoustic isolation is one of the problems raised with building construction in Spain. The publication of the Basic Document for the protection against noise of the Technical Building Code has increased the demand of comfort for citizens. This has created the need to seek new composite materials that meet the new required acoustical building codes. In this paper we report the results of the newly developed composites that are able to improve the acoustic isolation of airborne noise. These composites were prepared from polypropylene (PP) reinforced with mechanical pulp fibers from softwood (Pinus radiata). Mechanical and acoustical properties of the composites from mechanical pulp (MP) and polypropylene (PP) have been investigated and compared to fiberglass (FG) composites. MP composites had lower tensile properties compared with FG composites, although these properties can be improved by incorporation of a coupling agent. The results of acoustical properties of MP composites were reported and compared with the conventional composites based on fiberglass and gypsum plasterboards. Finally, we suggest the application of MP composites as a light-weight building material to reduce acoustic transmitions.

Two of the drawbacks of using natural-based composites in industrial applications are thermal instability and water uptake capacity. In this work, mechanical wood pulp was used to reinforce polypropylene at a level of 20 to 50 wt. %. Composites were mixed by means of a Brabender internal mixer for both non-coupled and coupled formulations. Differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA) were used to determine the thermal properties of the composites. The water uptake behavior was evaluated by immersion of the composites in water until an equilibrium state was reached. Results of water absorption tests revealed that the amount of water absorption was clearly dependent upon the fiber content. The coupled composites showed lower water absorption compared to the uncoupled composites. The incorporation of mechanical wood pulp into the polypropylene matrix produced a clear nucleating effect by increasing the crystallinity degree of the polymer and also increasing the temperature of polymer degradation. The maximum degradation temperature for stone ground wood pulp–reinforced composites was in the range of 330 to 345 ºC.

One of the most relevant properties of composite materials to be considered is stiffness. Fiberglass has been used traditionally as a fibrous reinforcing element when stiff materials are required. However, natural fibers are been exploited as replacements for synthetic fibers to satisfy environmental concerns. Among the different natural fibers, wood fibers show the combination of relatively high aspect ratio, good specific stiffness and strength, low density, low cost, and less variability than other natural fibers of such those from annual crops. In this work, composites from polypropylene and stone groundwood fibers from softwood were prepared and mechanically characterized under tensile loads. The Young’s moduli of the ensuing composites were analyzed and their micromechanics aspects evaluated. The reinforcing effect of stone groundwood fibers was compared to that of conventional reinforcement such fiberglass. The Halpin-Tsai model with the modification proposed by Tsai-Pagano accounted fairly for the behavior of PP composites reinforced with stone groundwood fibers. It was also demonstrated that the aspect ratio of the reinforcement plays a role in the Young’s modulus of injection molded specimens.

Two of the drawbacks of using natural-based composites in industrial applications are thermal instability and water uptake capacity. In this work, mechanical wood pulp was used to reinforce polypropylene at a level of 20 to 50 wt. %. Composites were mixed by means of a Brabender internal mixer for both non-coupled and coupled formulations. Differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA) were used to determine the thermal properties of the composites. The water uptake behavior was evaluated by immersion of the composites in water until an equilibrium state was reached. Results of water absorption tests revealed that the amount of water absorption was clearly dependent upon the fiber content. The coupled composites showed lower water absorption compared to the uncoupled composites. The incorporation of mechanical wood pulp into the polypropylene matrix produced a clear nucleating effect by increasing the crystallinity degree of the polymer and also increasing the temperature of polymer degradation. The maximum degradation temperature for stone ground wood pulp-reinforced composites was in the range of 330 to 345 ºC. [ABSTRACT FROM AUTHOR]

La clausura i la suspensió, en les activitats amb incidència ambiental sotmeses al règim de llicència i comunicació, en l'àmbit municipal, d'acord amb la regulació continguda a l'art. 53 de la Llei 3/1998, de 27 de febrer, de la intervenció integral de l'Administració ambiental, del Parlament de Catalunya