A comparative study between the fluxes of trace elements in bulk atmospheric deposition at industrial, urban, traffic, and rural sites

The input of trace elements via atmospheric deposition towards industrial, urban, traffic, and rural areas is quite different and depends on the intensity of the anthropogenic activity. A comparative study between the element deposition fluxes in four sampling sites (industrial, urban, traffic, and rural) of the Cantabria region (northern Spain) has been performed. Sampling was carried out monthly using a bulk (funnel bottle) sampler. The trace elements, As, Cd, Cr, Cu, Mn, Mo, Ni, Pb, Ti, Zn, and V, were determined in the water soluble and insoluble fractions of bulk deposition samples. The element deposition fluxes at the rural, urban, and traffic sites followed a similar order (Zn>Mn>>Cu=Ti>Pb>V=Cr>Ni>>As=Mo>Cd). The most enriched elements were Cd, Zn, and Cu, while V, Ni, and Cr were less enriched. An extremely high deposition of Mn was found at the industrial site, leading to high enrichment factor values, resulting from the presence of a ferro-manganese/silicomanganese production plant in the vicinity of the sampling site. Important differences were found in the element solubilities in the studied sites; the element solubilities were higher at the traffic and rural sites, and lower at the urban and industrial sites. For all sites, Zn and Cd were the most soluble elements, whereas Cr and Ti were less soluble. The inter-site correlation coefficients for each element were calculated to assess the differences between the sites. The rural and traffic sites showed some similarities in the sources of trace elements; however, the sources of these elements at the industrial and rural sites were quite different. Additionally, the element fluxes measured in the insoluble fraction of the bulk atmospheric deposition exhibited a good correlation with the daily traffic volume at the traffic site.The authors are grateful for the financial support from the CTM 2010-16068 (Spanish Ministry of Science and Innovation) and CTM 2013-43904 R (Spanish Ministry of Economy and Competitiveness) projects. The “Consejería de Medio Ambiente” from the Cantabria Government is also acknowledged for sending the report on the background levels of heavy metals and trace elements in soils in the Cantabria region. The authors are also grateful to “Ayuntamiento de Camargo” for helping us with the sampling site of Maliaño

Variability in metal deposition among industrial, rural and urban areas in the Cantabria region (Northern Spain)

Cantabria is a small region located in Northern Spain that combines different land uses; thus, urban, industrial and rural areas are present in a relatively small area (5300 km2); however, the anthropogenic influence is evident by studying the deposition of metals towards these areas. Three sampling sites (industrial, urban and rural) were selected to assess the variability in metal deposition. Sampling was carried out monthly (from January 2012 to July 2012) using a bulk (funnelbottle) sampler. As, Cd, Cr, Cu, Mn, Mo, Ni, Pb, Ti, Zn and V were determined in the water-soluble and in the insoluble fractions of deposition samples. The impact of the human activities in the industrial area can be seen on several metals such as Pb, Zn, Cu and Mn. The most obvious influence was found for Mn, high fluxes were measured in the industrial site with a mean value of 2260 μg/m2·day; in contrast to urban (99.6 μg/m2·day) and rural (15.3 μg/m2·day) areas. The lowest flux values were found in the rural area for all the elements. Enrichment Factor (EF) analysis were also studied for the three sites. The high EFs values found for Pb, Mn, Cu, and Zn (>100) in the industrial site point to significant anthropogenic sources, mainly originated from industrial activities (steel and ferro-manganese alloy manufacturing plants) and road traffic

Evolución de los mínimos de IMD en transistores HEMT´s: descripción usando una GM3 variante en el tiempo

In this paper, an alternative description of the small- to large-signal intermodulation distortion (IMD) evolution in PHEMT amplifiers is presented. The influence of the device derivatives on the nulls of the in-band distortion components of the channel current, and the origin of the linearity sweet spots are evaluated using the timedependence of the drain to source current third order derivatives as a novel technique for IMD null prediction

Exportación de puertas de aluminio de España a Venezuela: Gexpoalum, S.L.

Desarrollo de un proyecto de fin de Master de Comercio exterior sobre Exportación de puertas de aluminio de España a Venezuela. Se buscó un producto duradero y tecnológicamente desarrollado,a fin que sus características físicas permitiese cubrir de una forma adecuada las demandas existentes en el mercado internacional, bajo una rentabilidad aceptable y la factibilidad de una posible expansión a mediano plazo en la cuota de mercado. «Puertas de aluminio tipo sándwich». Este producto, que mantiene un alto nivel de competitividad en la UE y bajo coste por la tecnología empleada en su fabricación en España, se plantea explorar el nicho de negocio y la posible demanda existente en Sudamérica, en especial Venezuela, donde los últimos años ha aumentado considerablemente la expansión en el sector de la construcción en las zonas costeras.Los autores constituyeron la Empresa GEXPOALUM SL., la cual realizó los Estudios, linimientos estratégicos, trámites legales administrativos y de coordinación, así como de negocio para lograr conseguir el proveedor más adecuado, que nos ofrecerá el mejor precio con objeto de obtener una adecuada rentabilidad

Uso de los sweet-spots de gran señal en funciones de control de potencia de alta linealidad

In this paper a novel technique for controlling the output power in class B amplifiers is presented. The new approach uses the large-signal sweet-spots that appear in this operation mode, to optimize the linear behavior of the device and improve the amplifier power efficiency over the complete control range. A control strategy, based in a dual bias adjustment along the sweet-spots loci, is proposed to guarantee, at the same time, high linearity and high efficiency

Referencias corológicas de plantas vasculares en el NW ibérico

.

Nuevas aportaciones al Atlas de la Pteridoflora Ibérica y Balear (APIB

.

Análisis del comportamiento no lineal de un parche activo con control vectorial de señal

In this article an exhaustive study of the nonlinear behavior of a vector control active patch is presented. The potenciality for controlling the radiation pattern at the intermodulation distortion (IMD) components is shwon when this control unit is employed in linear arrays. Adequately selecting the phase value for the radiated field from each element, an improvement in the carrier to IMD ratio could be obtained in the main lobe direction. At last, a selective biasing technique is considered to increase the array linearity/efficiency trade off , with independence of the individual phase excitation

Técnica para mejorar la linealidad en arrays activos aprovechando sus propiedades de combinación espacial de potencia

In this paper, a linearity improving technique for active arrays, based on spatial power combining, is presented. An auxiliary branch is employed to cancel the radiation pattern at the intermodulation distortion (IMD) components in the main beam direction. The need for having a precise amplitude and phase control over the IMD currents in the array auxiliary elements is demonstrated, quantifying the possible degradation suffered in the Carrier to Intermodulation Distortion ratio (CIMD) improvement obtained when this solution is applied. The potentialities of implementing the derivative superposition technique in large-signal regimes in an array are finally proposed

Active reflectors: possible solutions based on reflectarrays and Fresnel reflectors

An overview about some of the recent Spanish developments on active reflectors is presented. In the first part, a novel beamsteering active reflectarray is deeply studied. It is based on implementing in each elementary radiator an IQ modulator structure, in which amplitude and phase control of the scattered field is achieved. Finally, a special effort is made in offering solutions to overcome the active antenna integration problems. In the second part, the active concept is firstly extended to Fresnel reflectors. Thanks to the development of a proper simulator, this special structure can be easily analysed. This simulator allows the study of performance of this kind of reflectors and, applying evolutionary algorithms, to find optimal configurations of reflector in accordance with the given specifications for the conformal radiation pattern