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Abstract  

Neutron scattering (NS) is a “big science” discipline whose research spans over a wide spectrum of fields, from fundamental or basic science to technological applications. The objective of this paper is to track the evolution of Spanish research in NS from a bibliometric perspective and to place it in the international context. Scientific publications of Spanish authors included in the Web of Science (WoS 1970–2006) are analysed with respect to five relevant dimensions: volume of research output, impact, disciplinary diversity, structural field features and internationalisation. NS emerges as a highly internationalised fast-growing field whose research is firmly rooted in Physics, Chemistry and Engineering, but with applications in a wide range of fields. International collaboration links -present in around 70% of the documents- and national links have largely contributed to mould the existing structure of research in the area, which evolves around major neutron scattering facilities abroad. The construction of a new European neutron source (ESS) would contribute to the consolidation of the field within the EU, since it will strengthen research and improve current activity.

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Abstract  

Due to an accidental release of transuranics at Palomares, Almeria (Spain), an area of 2.3 km2 was contaminated (1,2,3). With the objective of studying the possible transfer of the transuranic from land to sea (4), a sampling network for marine sediments and sea water was established between Cape Palos and Cape Gata. Concentrations of plutonium, americium and radiocesium were determined in sediment cores taken from the sea shelf surrounding Palomares. The depositional history of sediments was elucidated using the unsupported210Pb method. An increase in transuranic concentrations was observed off the southern coast of Palomares, the sources of which are discussed in this paper.

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Journal of Thermal Analysis and Calorimetry
Authors:
J. Pascual
,
F. Corpas
,
J. López-Beceiro
,
M. Benítez-Guerrero
, and
R. Artiaga

Abstract  

A Spanish red mud was thermally characterized. Chemical and mineralogical composition were determined by XRF and XRD.The thermal events observed in the range from room temperature to 1300°C were related to the sample composition. The first mass loss step was related to free water content, while many of the other processes were related to dehydration processes. It was found that most of the decomposition reactions of hydrohematite, ferrihydrite, aluminogoethite, boehmite, silicates and carbonates were strongly overlapping. It was also explained the formation of silicates and calcium titanate, which presence was confirmed at 1000°C by XRD.

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Abstract  

An instrumental method for sedimentation rate determination, using 210Pb natural radioactivity and the Constant Rate of Supply (CRS) model, is presented for the Santander Bay, Spain. Two sampling points were analyzed, one is affected industrially, and at the other, the industrial impact has been minimal. The results indicate a growth of the sedimentation rate in the two points studied, in the first point from 0.06 cm·y–1 to 0.35 cm·y–1, approximately from the beginning of the 20th century until the present time.The interrelation between the periods of maximum industrialization and the maximum variations in the sedimentation rate was investigated.

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The best alternative for reducing citrus production costs is mechanization. Machine vision is a reliable technology for the automatic inspection of fresh fruits and vegetables that can be adapted to harvesting machines. In these, fruits can be inspected before sending them to the packinghouse and machine vision provides important information for subsequent processing and avoids spending further resources in non-marketable fruit. The present work describes a computer vision system installed on a harvesting machine developed jointly by IVIA and a Spanish enterprise. In this machine, hand pickers directly drop the fruit as they collect it, which results in an important increase of productivity. The machine vision system is placed over rollers in order to inspect the produce, and separate those that can be directly sent to the fresh market from those that do not meet minimal quality requirements but can be used by the processing industry, based on color, size and the presence of surface damages. The system was tested under field conditions.

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Abstract  

U, Th and Ra isotopic activities have been measured in water and sediment samples collected over three years from the Guadalquivir river channel (South of Spain). The study of the radioactivity levels and activity ratios evolution in space and time has provided information on the behavior of the radionuclides mentioned above in the estuarine and non-estuarine zones of the river.

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Abstract  

The presence of224Ra and226Ra in waters from an estuarine system which surrounds a phosphate fertilizer complex (southwest Spain) has been studied. The high activities obtained confirm that an important radiological impact from such industrial complex on its close environment is being produced. The influence of tidal oscillations and seasonal conditions on activity concentration has also been investigated.

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Abstract  

The occurrence of anomalous enhancements of U-isotope activities in the surrounding environment of a phosphate fertilizer factory complex at the southwest of Spain has been established. It seems that significant amounts of U, released by such industries, are being accumulated in the environment, which may substantially contribute to the collective radiation dose received by the local population.

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Abstract  

The effect of sediment size, pH, temperature and conductivity on the transfer of uranium from sediment to water has been studied. The uranium concentration and the234U/238U,235U/238U activity ratios were measured in water, sediments and suspended matter sampled from Jucar River, using low level alpha-spectrometry. Distribution factors were obtained from these measurements. A more detailed sampling was done in the neighbourhood of the Cofrentes Nuclear Plant (Valencia, Spain). Total uranium activity,234U/238U activity ratio and distribution factors for234U and238U were found to vary with pH. Leaching and dilution, which depend on pH and salinity, are the probable mechanisms for these changes.

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Abstract  

The Odiel and Tinto rivers, southwest Spain, form a fully mixed estuary. An industrial area that includes a complex dedicated to the production of phosphate fertilizers is located by the Odiel River. This complex released phosphogypsum wastes directly to the Odiel River and also disposed them on open air piles located by the Tinto River. Due to new EU regulations, wastes are not directly released to the Odiel from 1998 on, although they are still disposed on the open air piles. The behavior of 226Ra in a system like this estuary is complex, since radionuclides are affected by tidal actions and interactions with sediments through adsorption/desorption reactions and erosion/deposition processes. A numerical 2D depth-averaged model of the estuary has been developed, including processes mentioned above. It has been applied to reproduce experimental data measured after a release from the industrial complex in the Odiel River and after an accidental release in the Tinto River from the gypsum piles. The model has also been applied to simulate the self-cleaning process observed in the estuary after the direct releases from the fertilizer complex were stopped.

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