Publications (11)15.11 Total impact
-
Article: Hydrology and Earth System Sciences Hydrogeothermal modelling vs. inorganic chemical composition of thermal waters from the area of Carballiño (NW Spain)
[show abstract] [hide abstract]
ABSTRACT: Hydrothermic features in Galicia (northwest Spain) have been used since ancient times for therapeutic purposes. A characterization of these thermal waters was carried out in order to understand their behaviour based on inorganic pattern and water-rock interaction mechanisms. In this way 15 thermal water samples were collected in the same hydrographical system. The selected thermal water samples were classified using principal component analysis (PCA) and partial least squares (PLS) regression analysis in two groups according to their chemical composition: group I with the young water samples and group II with the samples with longest water-rock contact time. This classification agreed with the results obtained by the use of geothermometers and hydrogeochemical modelling, where the samples were clas-sified into two categories according their residence time in the reservoir and their water-rock interaction.Hydrology and Earth System Sciences 01/2012; 16:157-166. · 3.15 Impact Factor -
Article: Removal of polycyclic aromatic hydrocarbons from organic solvents by ashes wastes.
[show abstract] [hide abstract]
ABSTRACT: Polycyclic aromatic hydrocarbons (PAHs) can be formed during the refinery processes of crude petroleum. Their removal is of great importance. The same happens with other organic solvents used for the extraction of PAHs (hexane, acetonitrile...), which can be polluted with PAHs. Kinetic and equilibrium batch sorption tests were used to investigate the effect of wood ashes wastes as compared to activated carbon on the sorption of three representative PAHs from n-hexane and acetonitrile. Mussel shell ashes were discarded for batch sorption experiments because they were the only ashes containing PAHs. The equilibrium time was reached at 16 h. Physical sorption caused by the aromatic nature of the compounds was the main mechanism that governed the PAHs removal process. Our investigation revealed that wood ashes obtained at lower temperature (300 degrees C) did not show any PAHs sorption, while ashes obtained at higher temperature (>500 degrees C) have adsorbent sites readily available for the PAH molecules. An increase in the molecular weight of PAHs has a strong effect on sorption wood ashes wastes. As low the wood ashes particle size as high the sorption of PAHs, as a result of differences in adsorbent sites. The performance of wood ash wastes vs. activated carbon to remove 10 PAHs from organic solvents is competitive in price, and a good way for waste disposal.Journal of hazardous materials 06/2010; 178(1-3):273-81. · 4.14 Impact Factor -
Article: Classification of thermal springs and wells waters through adamellite and granodiorite rocks based on inorganic pattern
[show abstract] [hide abstract]
ABSTRACT: Thermal waters are certainly a substantial asset of the Galicia region of Spain. They can be regarded as worth developing because of their human health implications and, if thermal tourism is promoted, their importance to the local economy. In this paper the chemistry of major and trace inorganic elements in about 45 thermal springs and wells discharging in the same hydrographical system are presented and discussed. For handling the results of all measurements, graphical representations of B/Li vs. SO4-2/Cl- ratios, Hill-Piper diagram, discriminant analysis (DA) and principal component analysis (PCA) were employed. All this with the intention to classify, based on their inorganic pattern, both thermal springs and wells waters, but also waters circulating through adamellite and granodiorite rocks. The results of the hydrogeochemistry analysis showed three main water families: sulphated, chlorurated and bicarbonated waters. The results show also the presence of saline materials with chloride influence in the deeper aquifer, allowing its classification in deeper and younger/shallow waters.Electronic Journal of Environmental, Agricultural and Food Chemistry. 01/2010; 9(1):188-198. -
Article: Behaviour of thermal waters through granite rocks based on residence time and inorganic pattern
[show abstract] [hide abstract]
ABSTRACT: Thermal waters are certainly a substantial asset of the Galicia region of Spain. They can be regarded as worth developing because of their human health implications and, if thermal tourism is promoted, their importance to the local economy. In this paper the chemistry of major and trace inorganic elements in about 45 thermal springs and wells discharging in the same hydrographical system are presented and discussed. For handling the results of all measurements, graphical representations of B/Li vs.SO42 - /Cl- ratios, Hill-Piper diagram, discriminant analysis (DA) and principal component analysis (PCA) were employed. All this with the intention to classify, based on their inorganic pattern, both thermal springs and wells waters, but also waters circulating through adamellite and granodiorite rocks. The results of the hydrogeochemistry analysis showed three main water families: sulphated, chlorinated and bicarbonated waters. The results show also the presence of saline materials with chloride influence in the deeper aquifer, allowing its classification in deeper and younger/shallow waters. © 2009 Elsevier B.V. All rights reserved.Journal of Hydrology. 01/2009; 373(3-4):329-336. -
Article: Behaviour of thermal waters through granite rocks based on residence time and inorganic pattern
[show abstract] [hide abstract]
ABSTRACT: Keywords: Chemistry of major and trace inorganic elements Granite rocks Thermal springs and wells Hill–Piper diagram Discriminant analysis Principal component analysis s u m m a r y Thermal waters are certainly a substantial asset of the Galicia region of Spain. They can be regarded as worth developing because of their human health implications and, if thermal tourism is promoted, their importance to the local economy. In this paper the chemistry of major and trace inorganic elements in about 45 thermal springs and wells discharging in the same hydrographical system are presented and discussed. For handling the results of all measurements, graphical representations of B/Li vs. SO 2À 4 /Cl À ratios, Hill–Piper diagram, discriminant analysis (DA) and principal component analysis (PCA) were employed. All this with the intention to classify, based on their inorganic pattern, both thermal springs and wells waters, but also waters circulating through adamellite and granodiorite rocks. The results of the hydrogeochemistry analysis showed three main water families: sulphated, chlorinated and bicarbon-ated waters. The results show also the presence of saline materials with chloride influence in the deeper aquifer, allowing its classification in deeper and younger/shallow waters.Journal of Hydrology 01/2009; 373:329–336. · 2.66 Impact Factor -
Article: Quaternary herbicides retention by the amendment of acid soils with a bentonite-based waste from wineries.
[show abstract] [hide abstract]
ABSTRACT: The agronomic utility of a solid waste, waste bentonite (WB), from wine companies was assessed. In this sense, the natural characteristics of the waste were measured, followed by the monitoring of its effects on the adsorption/desorption behaviour of three quaternary herbicides in acid soils after the addition of increasing levels of waste. This was done with the intention of studying the effect of the added organic matter on their adsorption. The high content in C (294 g kg(-1)), N (28 g kg(-1)), P (584 mg kg(-1)) and K (108 g kg(-1)) of WB turned it into an appropriate amendment to increase soil fertility, solving at the same time its disposal. WB also reduced the potential Cu phytotoxicity due to a change in Cu distribution towards less soluble fractions. The adsorption of the herbicides paraquat, diquat and difenzoquat by acid soils amended with different ratios of WB was measured. In all cases, Langmuir equation was fitted to the data. Paraquat (PQ) and diquat (DQ) were adsorbed and retained more strongly than difenzoquat (DFQ) in the acid soil studied. However, the lowest retention of DFQ in an acid soil can be increased by amendment with organic matter through a solid waste from wineries, and it is enough for duplicate retention a dosage rate of 10t/ha. Anyway, detritivores ecology can still be affected. Detritivores are the organisms that consume organic material, and in doing so contribute to decomposition and the recycling of nutrients. The term can also be applied to certain bottom-feeders in wet environments, which play a crucial role in benthic ecosystems, forming essential food chains and participating in the nitrogen cycle.Journal of hazardous materials 09/2008; 164(2-3):769-75. · 4.14 Impact Factor -
Article: The mobility and degradation of pesticides in soils and the pollution of groundwater resources
[show abstract] [hide abstract]
ABSTRACT: Pesticides, the most cost-effective means of pest and weed control, allow the maintenance of current yields and so contribute to economic viability. Concern about the environmental impact of repeated pesticide use has prompted research into the environmental fate of these agents, which can emigrate from treated fields to air, other land and waterbodies. How long the pesticide remains in the soil depends on how strongly it is bound by soil components and how readily it is degraded. It also depends on the environmental conditions at the time of application, e.g., soil water content. Pesticide use must ensure public safety and environmental protection with regards to both the chemical itself and their potentially harmful metabolites. This paper reviews what is known of the influence of the physical and chemical characteristics of the soil system, such as moisture content, organic matter and clay contents, and pH, on the sorption/desorption and degradation of pesticides and their access to groundwater and surface waters. An understanding of the fate of pesticides is essential for rational decision-taking regarding their authorization. To reach an adequate understanding will require the concourse of soil science, clay mineralogy, physical chemistry, surface chemistry, environmental microbiology, plant physiology and, no doubt, other disciplines. Only through a multidisciplinary approach to environmental research will it be possible to plan, manage, pursue and integrate the results of the studies that will be necessary for the development of tools and techniques allowing effective environmental decision-making. There seems to be a great potential to develop microbially derived pesticides, which are effective, reliable and have a low environmental risk. In addition, new application techniques, for example precision band spraying, can reduce the dose, which can be a very effective way to minimize transport and emission but also to avoid a build-up of resistance in target organisms. Improved formulations will also be needed to reduce off-target deposition, improve retention on target, and enhance uptake and translocation. © 2007 Elsevier B.V. All rights reserved.Agriculture, Ecosystems and Environment. 01/2008; 123(4):247-260. -
Article: Carbofuran sorption kinetics by corn crop soils.
Bulletin of Environmental Contamination and Toxicology 09/2006; 77(2):267-73. · 1.02 Impact Factor -
Article: Removal of polycyclic aromatic hydrocarbons from organic solvents by ashes wastes
[show abstract] [hide abstract]
ABSTRACT: Polycyclic aromatic hydrocarbons (PAHs) can be formed during the refinery processes of crude petroleum. Their removal is of great importance. The same happens with other organic solvents used for the extraction of PAHs (hexane, acetonitrile…), which can be polluted with PAHs. Kinetic and equilibrium batch sorption tests were used to investigate the effect of wood ashes wastes as compared to activated carbon on the sorption of three representative PAHs from n-hexane and acetonitrile. Mussel shell ashes were discarded for batch sorption experiments because they were the only ashes containing PAHs. The equilibrium time was reached at 16 h. Physical sorption caused by the aromatic nature of the compounds was the main mechanism that governed the PAHs removal process. Our investigation revealed that wood ashes obtained at lower temperature (300 °C) did not show any PAHs sorption, while ashes obtained at higher temperature (>500 °C) have adsorbent sites readily available for the PAH molecules. An increase in the molecular weight of PAHs has a strong effect on sorption wood ashes wastes. As low the wood ashes particle size as high the sorption of PAHs, as a result of differences in adsorbent sites. The performance of wood ash wastes vs. activated carbon to remove 10 PAHs from organic solvents is competitive in price, and a good way for waste disposal.Journal of Hazardous Materials. -
Article: Influence of major polyphenols on antioxidant activity in Mencía and Brancellao red wines
[show abstract] [hide abstract]
ABSTRACT: The purpose of this work was to examine the relationship of the total polyphenol index (TPI) as measured spectrophotometrically and individual phenols as determined by HPLC to antioxidant activity in red wines made from two Vitis vinifera grape varieties grown in NW Spain (viz. Mencía and Brancellao) during bottled storage in the dark for 12 months. Antioxidant activity was determined by using various methods based on inhibition of the coupled oxidation of the β-carotene/linoleic acid mixture. Also, free radical scavenging activity was determined with 2,2-diphenyl-1-picrylhydrazyl (DPPH). Antioxidant activity as measured by DPPH after storage for 3 months was higher in Mencía wines than in Brancellao wines (4.5 ± 0.60 vs. 3.7 ± 0.30 mmol/L trolox equivalents). Beyond 3 months of storage, radical scavenging activity increased in both types of wine (from 4.5 ± 0.60 to 6.0 ± 0.80 mmol/L in Mencía wines and from 3.7 ± 0.30 to 4.7 ± 0.71 mmol/L trolox equivalents in Brancellao wines). The significant correlation found between antioxidant activity and TPI in all wines (r > 0.88) is indicative of the significance of condensation and polymerisation products to the total antioxidant activity of the wines. The relatively high correlation of total flavonols (r = 0.89) and acylated anthocyanins (r = 0.70) as measured by HPLC with to the overall antioxidant capacity suggests that these two polyphenol classes can substantially influence the antioxidant properties of these wines. The linoleic acid/β-carotene assay exposed a higher antioxidant capacity in Brancellao wines than in Mencía wines after 3 months of storage (6.0 ± 0.80 vs. 4.7 ± 0.70). Most of the studied wines lost an average 45% antioxidant activity during bottled storage. Antioxidant activity as measured with the linoleic acid/β-carotene assay was closely correlated with both hydroxycinnamic acids (r = 0.90) and flavanols (r = 0.71 and 0.61 for monomeric and polymeric forms, respectively).Food Chemistry. -
Article: Behaviour of thermal waters through granite rocks based on residence time and inorganic pattern
[show abstract] [hide abstract]
ABSTRACT: Thermal waters are certainly a substantial asset of the Galicia region of Spain. They can be regarded as worth developing because of their human health implications and, if thermal tourism is promoted, their importance to the local economy. In this paper the chemistry of major and trace inorganic elements in about 45 thermal springs and wells discharging in the same hydrographical system are presented and discussed. For handling the results of all measurements, graphical representations of B/Li vs./Cl− ratios, Hill–Piper diagram, discriminant analysis (DA) and principal component analysis (PCA) were employed. All this with the intention to classify, based on their inorganic pattern, both thermal springs and wells waters, but also waters circulating through adamellite and granodiorite rocks. The results of the hydrogeochemistry analysis showed three main water families: sulphated, chlorinated and bicarbonated waters. The results show also the presence of saline materials with chloride influence in the deeper aquifer, allowing its classification in deeper and younger/shallow waters.Journal of Hydrology.
Top co-authors
Top Journals
Institutions
-
2006–2010
-
Universidade de Vigo
- • Department of Analytical and Food Chemistry
- • Facultad de Ciencias
Vigo, Galicia, Spain
-
