71 research outputs found
Quick and robust method for trace determination of MeHg in rice and rice products without derivatisation
Peer reviewedPostprin
Médicaments et aliments : approche ethnopharmacologique = Medicines and foods : ethnopharmacological approach
Que peut-on réellement entendre par "savoir", en quoi consiste-t-il et, partant, quelles nouvelles attitudes développer ? A partir des recherches rapportées, on peut se demander si la limite pour les substances nocives se situe au-dessous du seuil de risque, lequel est franchi à la suite d'écarts alimentaires. (Résumé d'auteur
Barriers towards food innovation for seniors : an exploratory study on perceptions of Swiss-German healthy independent seniors
Geochemistry of the thermal springs and fumaroles of Basse-Terre Island, Guadeloupe, Lesser Antilles
Mercury alkylation in freshwater sediments from Scottish canals
Funding This research was partly funded by award of a Strategic Educational Pathways Scholarship (Malta) to RC. Acknowledgement The authors wish to thank Scottish Canals (formerly British Waterways) for providing background information on the canal systems studied and granting permission to sample, and Dr Ana Teresa Reis (University of Aveiro) for conducting the Fe and S analysis in the Union Canal Sediments.Peer reviewedPostprin
Characterization of magmatic sulfur in the Aegean island arc by means of the δ34S values of fumarolic H2S, elemental S, and hydrothermal gypsum from Nisyros and Milos islands
A delta(34)S value of +6.3 +/- 1.5% was estimated for the rhyodacitic
degassing magma present underneath the hydrothermal system of Nisyros,
based on the S isotope ratios of H2S in fumarolic vapors. This value was
estimated by modeling the irreversible water-rock mass transfers
occurring during the generation of the hydrothermal liquid which
separates these fumarolic vapors. The S isotope ratio of the rhyodacitic
degassing magma of Nisyros is consistent with fractional crystallization
of a parent basaltic magma with an initial delta(34)S value of +4%
(+/-at least 1.5%). This positive value could be explained by mantle
contamination due to by either transference of fluids derived from
subducted materials or involvement of altered oceanic crust, whereas
contribution of biogenic sulfides from sediments seems to be negligible
or nil. This conclusion agrees with the lack of N-2 and CO2 from thermal
decomposition of organic matter contained in subducted sediments, which
is a characteristic of the whole Aegean arc system. Since hydrothermal S
at Milos and Santorini has isotope ratios similar to those determined at
Nisyros, it seems likely that common controlling processes are active
throughout the Aegean island arc. (C) 2002 Elsevier, Science B.V. All
rights reserved
Mercury alkylation in freshwater sediments from Scottish canals
Mercury concentrations were investigated in freshwater sediment from two
canals in Scotland, UK. High concentrations found in the Union Canal
(353-1200 mg kg(-1)) likely originate from historical munitions
manufacture, with lower levels in the Forth & Clyde Canal (0.591-9.14
mg kg(-1)). Concentrations of methylmercury (MeHg) were low - from 6.02
to 18.6 mu g kg(-1) (0.001-0.023% of total Hg) in the Union Canal and
from 3.44 to 14.1 mu g kg(-1) (0.11-0.58% of total Hg) in the Forth &
Clyde Canal - and there was a significant inverse relationship between
total Hg concentration and %MeHg. Total Hg concentration was
significantly negatively correlated with pH and positively correlated
with Fe content (in the Union Canal only) but not with organic matter, S
content or the proportion of clay present. The MeHg concentration was
not correlated with any of the above sediment parameters. Ethylmercury
was detected in the most highly contaminated sediments from the Union
Canal. (C) 2017 Elsevier Ltd. All rights reserved
Soil diffuse degassing and thermal energy fluxes from the southern Lakki plain, Nisyros (Greece)
Two diffuse soil CO2 flux surveys from the southern Lakki plain show
that CO2 is mainly released from the hydrothermal explosion craters. The
correspondence between high CO2 fluxes and elevated soil temperatures
suggests that a flux of hot hydrothermal fluids ascends towards the
surface. Steam mostly condenses near the surface and the heat given off
is conductively transferred to the atmosphere through the soil,
accompanied by a large CO2 flux. Tt was calculated, that 68 t d(-1) of
hydrothermal CO2 are released through the total surveyed area of similar
to1.3 km(2) Admitting that a steam flux of 2200 t d(-1) accompanies this
CO2 flux, the thermal energy released through steam condensation amounts
to 58 MW
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