Abstract. Alkenes are reactive hydrocarbons that influence local and regional atmospheric chemistry by playing important roles in the photochemical production of tropospheric ozone and in the formation of secondary organic aerosols. The simplest alkene, ethene (ethylene), is a major plant hormone and ripening agent for agricultural commodities. The group of light alkenes (C 2 -C 4 ) originates from both biogenic and anthropogenic sources, but their biogenic sources are poorly characterized, with limited field-based flux observations. Here we report net ecosystem fluxes of light alkenes and isoprene from a semiarid ponderosa pine forest in the Rocky Mountains of Colorado, USA using the relaxed eddy accumulation (REA) technique during the summer of 2014. Ethene, propene, butene and isoprene emissions have strong diurnal cycles, with median daytime fluxes of 123, 95, 39 and 17 µg m −2 h −1 , respectively. The fluxes were correlated with each other, followed general ecosystem trends of CO 2 and water vapor, and showed similar sunlight and temperature response curves as other biogenic VOCs. The May through October flux, based on measurements and modeling, averaged 62, 52, 24 and 18 µg m −2 h −1 for ethene, propene, butene and isoprene, respectively. The light alkenes contribute significantly to the overall biogenic source of reactive hydrocarbons: roughly 18 % of the dominant biogenic VOC, 2-methyl-3-buten-2-ol. The measured ecosystem scale fluxes are 40-80 % larger than estimates used for global emissions models for this type of ecosystem.
France wanted to be the world centre of science and culture at the time of the Universal World Exhibition in 1900 and therefore welcomed several international congresses to Paris that year, including the VIII International Geological Congress. Some of the participants and organisers of this meeting are described and the participants and contributions are analysed by country. Topics in physical geography, tectonics and mineral deposits attracted particular attention. The main Congress themes are described and details of the numerous field excursions are also provided. No major scientific advances occurred as a result of the Congress but it provided the opportunity for valuable exchanges of information and ideas and impetus to several fields.
RESUMENEn Morata de Tajuña y pueblos limítrofes hay una importante tradición yesera y calera, así como de otras industrias de materiales de la construcción ya desaparecidas, sobre todo en los años 60-70 del pasado siglo, debido a cambios en los sistemas productivos (paso de sistemas discontinuos a continuos, hornos mayores, etc.) (1). Por eso aún se conservan algunos hornos y también viven antiguos productores, a los que hemos podido preguntar sobre los procesos productivos.En el marco de un proyecto de investigación de la Consejería de Educación de la Comunidad de Madrid titulado "Arqueología Industrial: conservación del patrimonio minero-metalúrgico madrileño (IV)" se están identificando e inventariando viejas yeserías, recuperando la historia yesera local, reconstruyendo los flujos productivos y entrevistando a antiguos operarios. De esta manera, se pretende evaluar el estado del patrimonio, planteando la conservación de algunos de estos elementos.Palabras claves: hornos morunos, yeso, cal, cemento, Madrid. SUMMARYIn the locality of Morata de Tajuña and surroundings there was an important settlement of gypsum pits and limekilns, together with other historical industries, now disappear. These activities were developed mainly during the 1960´s and 70´s, but its production decreased because of changes in the productive processes (substitution of discontinuous processes by continuous ones, higher kilns, etc.) (1). Nevertheless, some of these furnaces still remain, as well as ancient workers who have provided important information.Within the research project funded by the Madrid´s Government, entitled: Industrial archaeology: Conservation of the mining and metallurgical heritage of Madrid (IV), ancient gypsum pits have been identified and inventoried. The ancient gypsiferous extraction history was recovered and the productive processes fluxes were reconstructed. The state of the heritage is evaluated and the conservation of some of the elements is recommended. Likewise, the intangible heritage was also investigated, being able to show a legend related with these kilns.
RESUMENUno de los objetivos del proyecto "Desarrollo de la herramienta eCompetentis para la evaluación de competencias transversales" (EA2009-0040) PALABRAS CLAVEEvaluación, competencias genéricas, competencias transversales, portal web, instrumentos psicométricos, trabajo en equipo, resolución de problemas. ABSTRACT One of the aims of the project "Development of eCompetentis tool for assessing generic competences" (EA2009-0040) funded by the Ministry of Education and
Mining activity is the second biggest producer of waste in the European Union (EU), so to develop processes that allow the reuse of waste and the consequent creation of markets for these secondary raw materials are relevant for a desirable transition to a circular economy. Copper waste such as cakes, tailings, pyrite roasting residues, or slags present very different physical characteristics and hazards. There are two important aspects to consider for the residue of hazardous determination and its reuse: the particle size and the leaching behavior. Also, the reactive or non-reactive property of the waste depends on their origin, which is important for new applications. Based on these parameters (and other specifics for each application), the intention of this paper is to review and study the different applications of copper residues, aiming for new possibilities of cement-based construction materials with added value that allow to economically justify the use of cement.
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