Due to the renewed interest for sites of geological interest, both in nature conservation and tourist sectors, numerous regional and national geosite inventories have been carried out in several countries during the last two decades. Several research groups discussed methodological issues, in particular concerning the assessment, and proposed various assessment methods. The University of Lausanne developed a method for assessing the scientific and additional values of geomorphosites in 2007. The method was widely used in regional inventories in Switzerland and abroad. This paper presents a new version of the method and discusses four main issues: (1) the assessment methodology is included in a larger process, from the selection of potential geomorphosites to their use and evaluation by stakeholders; (2) a particular attention is put on the selection of potential geomorphosites that will then be assessed and a simple approach crossing a spatial selection (the selected geomorphosites should be representative of the regional geomorphological processes) and a temporal one (the selected geomorphosites should cover the whole temporal stages of the regional morphogenesis, with both relict and active landforms) is proposed; (3) a new part is added in the assessment method; it concerns the use characteristics and fills a gap in the existing method; (4) finally, the paper discusses mapping and representation issues: specific maps are produced at two levels: simple geomorphological maps accompany the assessment of each geomorphosite and synthetic maps, covering the whole study area, are produced for the communication of results to stakeholders. For this, four types of representation (qualitative, univariate, bivariate, multivariate) are proposed. The method is illustrated by three examples of inventories carried out in Western Switzerland and Haute-Savoie (France).

Lors de l’élaboration de produits géotouristiques, l’essentiel de l’attention est porté au site et au support — panneau, brochure ou appareil mobile. C’est du moins ce qui ressort ces dernières années des colloques scientifiques consacrés au géotourisme. Bien qu’essentielles, les considérations relatives aux processus de médiation ou aux approches méthodologiques pour la valorisation géotouristique demeurent rares. Cet article tente une formalisation du processus d’élaboration des produits géotouristiques. Quatre domaines sont identifiés — le public, le site, le contenu et le support — qui soulèvent une série de questions. Leur résolution vise à obtenir un produit de médiation cohérent, base nécessaire à une entreprise didactique. Est-ce que la réalisation est adaptée au site et à ses particularités, intéresse le public, est structurée de manière à rendre possible la transmission d’un message ? Sur cette même base est présentée une ébauche de méthode d’évaluation des produits, portant à la fois sur la qualité scientifique et la qualité de la démarche didactique. L’importance d’évaluations complémentaires sur la réelle efficacité didactique et les retombées socio-économiques de ces produits est signalée. L’ensemble de ces démarches vise à augmenter la qualité générale des produits géotouristiques et à leur permettre d’atteindre leurs buts didactiques ou de sensibilisation.

clinicaltrials.gov Identifier: NCT01455454.

conditions. Such a low value requires reducing air molecule mobility in highly porous materials, and silica-based superinsulation materials (SIM) made of packed nanostructured silica or aerogel are good candidates for this purpose. However, the native nanostructure of silica has never been imaged or characterized up to now, making SIM optimization quite difficult. In this paper, three nanostructured commercial silica samples prepared by different synthesis methods were analysed and quantified using advanced electron tomography, N 2 physisorption, mercury porosimetry and helium pycnometry. It was demonstrated that 3D images yield a much finer description of the microstructure (particle, aggregate and pore) compared to global measurements. For the samples studied, silica particle size is dependent on the synthesis method, increasing with pore diameter size. The smallest silica particles were obtained by the sol-gel method which also provides the smallest pore diameters, the smallest and rather spherical aggregates, and the lowest thermal conductivity. The pyrogenic and precipitated samples studied presented bigger silica particles with higher pore diameters and thus higher thermal conductivities. 3Dimage driven characterization opens up new synthesis opportunities for silica.

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SummaryFor insulation applications, boards thinner than 2 cm are under design with specific thermal conductivities lower than 15 mW m −1 K −1 . This requires binding slightly hydrophobic aerogels which are highly nanoporous granular materials. To reach this step and ensure insulation board durability at the building scale, it is compulsory to design, characterise and analyse the microstructure at the nanoscale. It is indeed necessary to understand how the solid material is formed from a liquid suspension. This issue is addressed in this paper through wet-STEM experiments carried out in an Environmental Scanning Electron Microscope (ESEM). Latex-surfactant binary blends and latex-surfactant-aerogel ternary systems are studied, with two different surfactants of very different chemical structures. Image analysis is used to distinguish the different components and get quantitative morphological parameters which describe the sample architecture. The evolution of such morphological parameters during water evaporation permits a good understanding of the role of the surfactant.

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