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The solubilization of n-hexane and toluene by silicate-surfactant hexagonal mesophases has been studied by time-resolved in situ synchrotron small-angle X-ray scattering. It is suggested that the extent of solubilization is mainly governed by the oil solubility in the continuous phase. The availability of the oil will largely influence the phase behavior and the long-range order of the silicatropic mesophase. While the addition of n-hexane to the synthesis results in a loss of order, a substantial amount of toluene can be solubilized without affecting the long-range order. Many of the observed effects can be rationalized based on time-dependent changes in the properties of the system due to silicate hydrolysis and condensation reactions, in addition to the water solubility of the solubilizate. The results are compared with those obtained for corresponding systems in the absence of silica.

Abstract. Strong winds may uproot and break trees and represent a major natural disturbance for European forests. Wind disturbances have intensified over the last decades globally and are expected to further rise in view of the effects of climate change. Despite the importance of such natural disturbances, there are currently no spatially explicit databases of wind-related impact at a pan-European scale. Here, we present a new database of wind disturbances in European forests (FORWIND). FORWIND is comprised of more than 80 000 spatially delineated areas in Europe that were disturbed by wind in the period 2000–2018 and describes them in a harmonized and consistent geographical vector format. The database includes all major windstorms that occurred over the observational period (e.g. Gudrun, Kyrill, Klaus, Xynthia and Vaia) and represents approximately 30 % of the reported damaging wind events in Europe. Correlation analyses between the areas in FORWIND and land cover changes retrieved from the Landsat-based Global Forest Change dataset and the MODIS Global Disturbance Index corroborate the robustness of FORWIND. Spearman rank coefficients range between 0.27 and 0.48 (p value < 0.05). When recorded forest areas are rescaled based on their damage degree, correlation increases to 0.54. Wind-damaged growing stock volumes reported in national inventories (FORESTORM dataset) are generally higher than analogous metrics provided by FORWIND in combination with satellite-based biomass and country-scale statistics of growing stock volume. The potential of FORWIND is explored for a range of challenging topics and scientific fields, including scaling relations of wind damage, forest vulnerability modelling, remote sensing monitoring of forest disturbance, representation of uprooting and breakage of trees in large-scale land surface models, and hydrogeological risks following wind damage. Overall, FORWIND represents an essential and open-access spatial source that can be used to improve the understanding, detection and prediction of wind disturbances and the consequent impacts on forest ecosystems and the land–atmosphere system. Data sharing is encouraged in order to continuously update and improve FORWIND. The dataset is available at https://doi.org/10.6084/m9.figshare.9555008 (Forzieri et al., 2019).

Mesoscopically ordered silicate-surfactant composite materials of the M41S type synthesized in the presence of a swollen agent have been characterized by in situ and ex situ X-ray diffraction analysis. The key feature of the room-temperature synthesis is the use of a mixture of cationic and anionic surfactants as structure-directing agents. The lower interfacial charge density of the mixed surfactant aggregates stabilizes structures of lower interfacial curvature and therefore facilitates a more controlled solubilization of organic swelling agents. An increased solubilization capacity of the catanionic surfactant-silicate mesophase was observed close to an anionic/cationic surfactant ratio corresponding to a transition to the lamellar phase in the absence of toluene. In the presence of toluene, the catanionic template stabilizes microemulsion droplets that serve as building blocks for the final material. However, a fair amount of organic compound is solubilized in the silica-catanionic surfactant composite after the mesophase is formed. Although the present communication concerns mesoporous silica, the concept is a general one and may allow the synthesis of non-siliceous large-pore materials.