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GC chromatograms and photos of extracts

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Highly porous carbon-silica composites (CSC) were prepared for the first time through a simple wet impregnation process and subsequent pyrolysis of low-value sugarcane by-products, namely molasses. These CSC materials demonstrate a distinct range of functionalities, which significantly differ from similar materials published in the literature. Importantly, the carbon-silica composites prepared at 800°C exhibited exceptional adsorption capacities for the azo-dye congo red (445 mg g−1), due to the graphitic carbon coating and unique functionality including C-O-C within the porous structure. Congo red adsorption capacity of the highly mesoporous graphitic carbon-silica composites significantly exceeds that of commercial activated carbon and silica, these carbon-silica composites therefore represent an effective step towards the development of porous bio-derived adsorbent for remediation of dye wastewaters. Both the porous properties (surface area and pore size distribution) and the functionality of the carbon coating were dependent on the temperature of preparation. The sustainable synthetic methods employed led to a versatile material that inherited the mesoporosity characteristics from the parent silica, demonstrating mesoporous volumes greater than 90% (as calculated from the total pore volume). Adsorption on the 800°C prepared carbon-silica composites demonstrated an excellent fit with the Langmuir isotherm and the pseudo-first-order kinetic model.

Although a promising technique, phytoextraction has yet to see significant commercialization. Major limitations include metal uptake rates and subsequent processing costs. However, it has been shown that liquid-culture-grown Arabidopsis can take up and store palladium as nanoparticles. The processed plant biomass has catalytic activity comparable to that of commercially available catalysts, creating a product of higher value than extracted bulk metal. We demonstrate that the minimum level of palladium in Arabidopsis dried tissues for catalytic activity comparable to commercially available 3% palladium-on-carbon catalysts was achieved from dried plant biomass containing between 12 and 18 g·kg(-1) Pd. To advance this technology, species suitable for in-the-field application: mustard, miscanthus, and 16 willow species and cultivars, were tested. These species were able to grow, and take up, palladium from both synthetic and mine-sourced tailings. Although levels of palladium accumulation in field-suitable species are below that required for commercially available 3% palladium-on-carbon catalysts, this study both sets the target, and is a step toward, the development of field-suitable species that concentrate catalytically active levels of palladium. Life cycle assessment on the phytomining approaches described here indicates that the use of plants to accumulate palladium for industrial applications has the potential to decrease the overall environmental impacts associated with extracting palladium using present-day mining processes.

The global bio-based chemical market is growing in size and importance. Bio-based solvents such as glycerol and 2-methyltetrahydrofuran are often discussed as important introductions to the conventional repertoire of solvents. However adoption of new innovations by industry is typically slow. Therefore it might be anticipated that neoteric solvent systems (e.g., ionic liquids) will remain niche, while renewable routes to historically established solvents will continue to grow in importance. This review discusses bio-based solvents from the perspective of their production, identifying suitable feedstocks, platform molecules, and relevant product streams for the sustainable manufacturing of conventional solvents.

Prepara a los estudiantes para el nivel A2 en las especificaciones Edexcel y tiene como apoyo un sitio web con la versión interactiva del libro pero reforzada con recursos adicionales como tutoriales audiovisuales, hojas de datos, resultados del aprendizaje y orientación sobre habilidades prácticas. SC Biblioteca de Educación del Ministerio de Educación, Cultura y Deporte; Calle San Agustín, 5 - 3 planta; 28014 Madrid; Tel. +34917748000; biblioteca@mecd.es GBR

Se describe el curso de bachillerato 'Ciencia divulgativa' y se explican las bases en las que se fundamenta. Muesta como un curso sobre un tema específico y bien diseñado puede servir para consolidar de un modo sistemático la comprensión de los estudiantes sobre algunas importantes explicaciones científicas y cuestiones relacionadas con la ciencia. ibliografía p. 29. Cataluña Universidad de Valladolid. Facultad de Educación. Biblioteca; Calle Geólogo Francisco Hernández Pacheco, s-n; 47014 Valladolid; Tel. +34983423435; Fax +34983423436; redinet@uva.es ESP

Fractal dimension has been used extensively as a descriptor of the rugged outlines of fine-particles. Potentially, it may be a useful parameter for characterizing the outlines of fine-particles which have been subjected to some form of chemical degradation. Here, fractal dimension values have been computed for the outlines of microscopic lead fine-particles both before and after weak hydrochloric acid dissolution experiments. Values obtained for the post-dissolution rugged profiles were greater than those of the pristine fracture grains which had a Euclidean form. The profiles of the degraded fine-particles could be characterized by a single fractal dimension value, or they exhibited multi fractal behavior. Data from profiles of fine-particle lead from the natural environment of the soil suggest that fractal dimension calculations may provide a useful descriptor for particles which have undergone chemical dissolution and transformation in such an environment.

Over 400 cases with data from in situ electron microprobe quantitation of non-fibrous inorganic particles (e.g., silica, alumino-silicates, talc, metals) in pulmonary tissue sections, and data from quantitative digestion analyses for fiber content (e.g., asbestos, silica, alumino-silicates, man-made fibers, talc) comprise an extensive microcomputer data set of lung particle burden. When allied with demographic and histopathologic information the result is a comprehensive database of occupational pulmonary pathology. Examples of the kinds of information which can be extracted from the database include: 1) summary information on the types sizes and associations of particles in lungs with a variety of exposures, 2) concentrations of etiologic particle type in cases with recognized pneumoconioses, and 3) correlations between particle type, pathology, occupation and social history. The database provides a powerful tool for assessing such information on statistically meaningful sample sets.