Time filter

Source Type

Santa Cruz de Tenerife, Spain

Socas-Rodriguez B.,University of La Laguna | Herrera-Herrera A.V.,University of La Laguna | Asensio-Ramos M.,Instituto Volcanologico Of Canarias Involcan | Hernandez-Borges J.,University of La Laguna
Journal of Chromatography A | Year: 2014

Carbon nanotubes (CNTs) are still awakening scientists' interest because of their inherent properties as well as their applications in a wide variety of fields. Regarding Analytical Chemistry, and although they have also been used as stationary phases in chromatography or pseudostationary phases in capillary electrophoresis, they have also found a particular place in sorbent-based extraction techniques. In fact, they are currently used as sorbents in solid-phase extraction, solid-phase microextraction, stir-bar sorptive extraction and matrix solid-phase dispersion, for analyte enrichment or storage, sample fractionation or clean-up as well as support for derivatization reactions. CNT surface is tuneable and, as a result, they can be suitably functionalized, aggregated or linked to other supports which increase their potential use as sorbents. They can also be arranged under different formats (cartridges, fibers, stir bars, disks, etc.) or even combined with magnetic nanoparticles, which clearly enlarge their applications. This review article overviews the most recent applications of CNTs as sorbent materials, covering the period from 2010 to early 2014. © 2014 Elsevier B.V. Source

D'Orazio G.,CNR Methodological Chemistry Institute | D'Orazio G.,University of La Laguna | Asensio-Ramos M.,Instituto Volcanologico Of Canarias Involcan | Fanali C.,Biomedical University of Rome | And 2 more authors.
TrAC - Trends in Analytical Chemistry | Year: 2016

Capillary electrochromatography (CEC) is a miniaturized technique which gathers the high separation efficiency of capillary electrophoresis and the selectivity of liquid chromatography, being a very interesting hybrid separation procedure. It requires a small amount of solvents and samples, having a high impact in the total cost of the analysis. For these reasons, CEC has aimed a relatively big potential, especially in the fields of pharmaceutics and biomedicine analysis. Nonetheless, food analysis has also been of interest for a considerable number of researchers who have focused their efforts in this direction. This review article shows a deep examination of the use of CEC in food safety and food quality, from the first application in 1997 to the present, commenting those with a higher impact or novelty. © 2016 Elsevier B.V. Source

Doniz-Paez J.,University of La Laguna | Doniz-Paez J.,Instituto Volcanologico Of Canarias Involcan
Geomorphology | Year: 2015

This paper proposes a method to establish a morphological classification of Tenerife's cinder cones on the basis of a dual analysis of qualitative (existence, geometry and disposition of craters) and quantitative morphometric parameters (major and minor diameters and cone elongation, major and minor diameters and crater elongation). The result obtained is a morphological classification of the cinder cones of Tenerife, which can be sub-divided into four types: ring-shaped-cones, horseshoe-shaped-volcanoes, multiple volcanoes and volcanoes without crater. In Tenerife there is a clear dominance of horseshoe-shaped volcanoes (69.0%) over ring-shaped cones (13.1%), volcanoes without craters (11.4%) and multiple volcanoes (6.4%). The classification presented in this paper is characterized by its simplicity which makes it possible to include all morphological types of volcanoes found in Tenerife. This fact also renders our classification a useful tool to apply in other, both insular and continental volcanic areas to eventually analyze and systematize the study of eruptive edifices with similar traits. © 2014 Elsevier B.V. Source

Chester D.,Liverpool Hope University | Chester D.,University of Liverpool | Duncan A.,University of Liverpool | Kilburn C.,University College London | And 3 more authors.
Journal of Volcanology and Geothermal Research | Year: 2015

Cultural and political contexts are important in determining the ways in which communities respond to volcanic eruptions. Understanding the manner in which communities and the State apparatus have coped with historic eruptions can provide insights into how responses have influenced vulnerability and resilience. The 1906 eruption of Vesuvius is well suited for such a study as it was one of the first major eruptions in which there was a significant element of State control, and this worked alongside more traditional pre-industrial responses. This eruption was extensively reported in the regional, national and international press and in archives which include still photography. One feature is the rich archive of material published in English language newspapers of record which are analysed fully in the paper for the first time. Many of these data sources are now accessible on-line. The eruption started on April 4th with mild explosive activity and the eruption of lava from 5th to 7th April. On the night of the 7th/8th, activity intensified when a vigorous lava fountain inclined obliquely to the north east, deposited a thick layer of tephra on the towns of Ottaviano and San Giuseppe. This led to roof collapse and a large number of fatalities. There was increased lava emission and a flow progressed south through the outskirts of Boscotrecase cutting the Circumvesuviana railway line and almost reaching Torre Annunziata. Following April 8th the eruption declined and ended on April 21st. In the initial responses to the eruption pre-industrial features were prominent, with the local communities showing social cohesion, self-reliance and little panic. A more negative aspect was the traditional religious response that involved the use of liturgies of divine appeasement and which included the use of saintly relics and images. There is interesting evidence, however, that this coping strategy was driven by the populace rather than by the clergy. The inhabitants of San Giuseppe, for instance, insisted in taking refuge in a church and this led to over 100 fatalities when the roof collapsed. Intervention by the State included: the effective deployment of troops to handle evacuation, to re-open lines of communication and to distribute food and other relief. Management of the disaster was enhanced when prefectural commissioners were given executive powers. We argue that increased State intervention appears to have reduced self-reliance. In the short-term recovery was supported by regional/state aid and by charitable donations particularly from other governments and members of Neapolitan diaspora in other parts of Italy and abroad. This enabled land clearance, agriculture was re-established and roads/rail links were restored. Long-term recovery was slow with affected local-authorities (i.e., comuni) showing low rates of population growth for more than 15. years. © 2015 Elsevier B.V. Source

D'Orazio G.,National Research Council Italy | D'Orazio G.,University of La Laguna | Hernandez-Borges J.,University of La Laguna | Asensio-Ramos M.,Instituto Volcanologico Of Canarias Involcan | And 2 more authors.
Electrophoresis | Year: 2016

Nano-LC and CEC were coupled to MS through a nanospray or a pressurized liquid-junction interface for the simultaneous separation and determination of 11 estrogenic compounds. Different stationary phases, that is, phenyl, C18, and C18 bidentate silica hydrate, were studied. For both techniques, the phenyl stationary phase was the best option, considering separation efficiency, selectivity, and resolution. Under the optimized conditions, the baseline separation of the target compounds (including estradiol and zearalanol epimers) was achieved in less than 20 min in nano-LC-MS and less than 13 min in CEC-MS. Molecular imprinted polymer SPE was used for extracting the target compounds from mineral water samples with the analysis of nano-LC-MS. The whole molecular imprinted polymer SPE nano-LC-MS method was validated through a recovery study at two levels of concentration. Sensitivity was improved by on-column focusing technique obtaining LODs in the range 1.4-55.4 ng/L. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim. Source

Discover hidden collaborations