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Trace element (TE) speciation modelling in soil solution is controlled by the assumptions made about the soil solution composition. To evaluate this influence, different assumptions using Visual MINTEQ were tested and compared to measurements of free TE concentrations. The soil column Donnan membrane technique (SC-DMT) was used to estimate the free TE (Cd, Cu, Ni, Pb and Zn) concentrations in six acidic soil solutions. A batch technique using DAX-8 resin was used to fractionate the dissolved organic matter (DOM) into four fractions: humic acids (HA), fulvic acids (FA), hydrophilic acids (Hy) and hydrophobic neutral organic matter (HON). To model TE speciation, particular attention was focused on the hydrous manganese oxides (HMO) and the Hy fraction, ligands not considered in most of the TE speciation modelling studies in soil solution. In this work, the model predictions of free ion activities agree with the experimental results. The knowledge of the FA fraction seems to be very useful, especially in the case of high DOM content, for more accurately representing experimental data. Finally, the role of the manganese oxides and of the Hy fraction on TE speciation was identified and, depending on the physicochemical conditions of the soil solution, should be considered in future studies. [ABSTRACT FROM AUTHOR]

Abstract: Both losses of dissolved CO2, and fluxes of gaseous CO2 escaping from a Champagne wine served in laser-etched INAO glasses showing an increasing number of bubble nucleation sites, were examined, all along the first 10min following pouring. Logically, the more intense the effervescence is into a glass, the more rapid its progressive loss of dissolved CO2. Moreover, during the first minutes following pouring, the higher the number of laser beam's points of impact is in glasses, the higher the fluxes of gaseous CO2 escaping from the champagne surface. Nevertheless, and quite counter intuitively, from approximately 3min after pouring, the highest levels of gaseous CO2 fluxes escaping champagne were not sustained from glasses with the highest number of bubble trains. This experimental observation was discussed on the basis of a theoretical bubbling model. It was finally demonstrated that the flux of gaseous CO2 desorbing from the liquid phase is the result of a balance between the intensity of effervescence, and the dissolved CO2 concentration found in champagne. [Copyright &y& Elsevier]

• Salt-contaminated stones were characterized by active infrared thermography (IRT). • Salt uptake mass and location depended on stone type and on salt type and concentration. • Active IRT helps determining salt type and concentration non-destructively at early stages of weathering. The accumulation of salts in building stones can lead to weathering features such as scaling, sanding or even slab detachment. To detect salts in walls at the early stages and to predict their evolution, the non-destructive technique (NDT) Infrared Thermography (IRT) was tested in a stimulated way. The main objective was to trial this technique in order to obtain more information such as the type of salt, its precise location and its concentration in building stones. Three building materials were studied, including two natural limestones and a reconstituted stone. Samples were submitted to immersion/drying tests in water and in salt solutions of Na 2 SO 4 , NaCl and MgSO 4 at 7%, 14% and 26% in weight during 20 cycles of 24 h. The weight of the samples and the surface colour were recorded after each cycle. After 1, 5, 10 and 15 cycles, 3 samples were taken out for active IRT measurements. The results showed that when the porosity and the capillarity are low, the intake of salts into the porous network is low and the thermal response of the stone to heating (ΔTmax) corresponds to the salt thermal signature and has no relation with concentration. On the other hand, when the initial porosity is high, salts crystallize inside the porous network and porosity decreases. Hence, the thermal response of the porous stone is related to salt concentration and the ΔTmax increases until the stone starts to disaggregate. Active IRT is a promising NDT adapted to identify and quantify salts within building stones during the first states of accumulation. [ABSTRACT FROM AUTHOR]

Anthropogenic inputs of trace elements (TE) into soils constitute a major public and environmental health problem. Bioavailability of TE is strongly related to the soil physicochemical parameters and thus to the ecosystem type. In order to test whether soil parameters influence the response of the bacterial community to TE pollution, we collected soil samples across contrasting ecosystems (hardwood, coniferous and hydromorphic soils), which have been contaminated in TE and especially lead (Pb) over several decades due to nearby industrial smelting activities. Bacterial community composition was analysed using high throughput amplicon sequencing and compared to the soil physicochemical parameters. Multivariate analyses of the pedological and biological data revealed that the bacterial community composition was affected by ecosystem type in the first place. An influence of the contamination level was also evidenced within each ecosystem. Despite the important variability in bacterial community structure, we found that specific bacterial groups such as γ- Proteobacteria , Verrucomicrobia and Chlamydiae showed a consistent response to Pb content across contrasting ecosystems. Verrucomicrobia were less abundant at high contamination level whereas Chlamydiae and γ- Proteobacteria were more abundant. We conclude that such groups and ratio's thereof can be considered as relevant bioindicators of Pb contamination. [ABSTRACT FROM AUTHOR]

Smelting activities are one of the most common sources of trace elements in the environment. The aim of this study was to determine the lead distribution in upper horizons (0–5 and 5–10 cm) of acidic soils in the vicinity of a lead-acid battery recycling plant in northern France. The combination of chemical methods (sequential extractions), physical methods (Raman microspectroscopy and scanning electron microscopy with an energy dispersive spectrometer) and multi-surface complexation modelling enabled an assessment of the behaviour of Pb. Regardless of the studied soil, none of the Pb-bearing phases commonly identified in similarly polluted environments (e.g., anglesite) were observed. Lead was mainly associated with organic matter and manganese oxides. The association of Pb with these soil constituents can be interpreted as evidence of Pb redistribution in the studied soils following smelter particle deposition. [ABSTRACT FROM AUTHOR]

Abstract: A cell suspension culture was developed from calli of grape rootstock 41B in order to study the bioproduction of resveratrol. While 41B grape cultures produced no resveratrol, methyljasmonate (MeJA) elicitor treatment activated its production in a dose dependent manner. The concentration of 0.2mM MeJA was optimal for efficient production and high accumulation of resveratrol (150mg/L) in flask experiments. Microscopic analysis of cells monitored for viability showed that MeJA elicitor triggered expression of resveratrol fluorescence within the cells. These results led to scale-up of the culture in a 2L stirred bioreactor where a resveratrol production of 209mg/L being secreted into the liquid medium, corresponding to 90% of the total production. Liquid/liquid extraction of the culture medium and a solid/liquid extraction of the cells showed that other stilbenes were also produced. For the first time, trans-ɛ-viniferin, trans-δ-viniferin, and a trans-3-methylviniferin as well as trans-piceatannol were identified in a 2L bioreactor cell cultures of grapevine. Furthermore, a one step FPLC method was developed for the purification of resveratrol and ɛ-viniferin. [Copyright &y& Elsevier]