7 research outputs found
ARTEFACTS: How do we want to deal with the future of our one and only planet?
The European Commissionâs Science and Knowledge Service, the Joint Research Centre (JRC), decided to try working hand-in-hand with leading European science centres and museums.
Behind this decision was the idea that the JRC could better support EU Institutions in engaging with the European public. The fact that European Union policies are firmly based on scientific evidence is a strong message which the JRC is uniquely able to illustrate. Such a collaboration would not only provide a platform to explain the benefits of EU policies to our daily lives but also provide an opportunity for European citizens to engage by taking a more active part in the EU policy making process for the future.
A PILOT PROGRAMME
To test the idea, the JRC launched an experimental programme to work with science museums: a perfect partner for three compelling reasons. Firstly, they attract a large and growing number of visitors. Leading science museums in Europe have typically 500 000 visitors per year. Furthermore, they are based in large European cities and attract local visitors as well as tourists from across Europe and beyond.
The second reason for working with museums is that they have mastered the art of how to communicate key elements of sophisticated arguments across to the public and making complex topics of public interest readily accessible. That is a high-value added skill and a crucial part of the valorisation of public-funded research, never to be underestimated.
Finally museums are, at present, undergoing something of a renaissance. Museums today are vibrant environments offering new techniques and technologies to both inform and entertain, and attract visitors of all demographics.JRC.H.2-Knowledge Management Methodologies, Communities and Disseminatio
Développement de catalyseurs pour le transfert d'hydrogÚne : application à des molécules biosourcées
In this study, we evaluated the compatibility of polyfunctional alcohols with catalytic aerobic oxidation systems. Geraniol dehydrogenation was carried out in mild conditions (t-BuOH / water mixture as solvent, 40°C) in the presence of Pt / C (promoted with Bi to avoid leaching). These catalysts are efficients for the oxidation of 8-Chloro-1-Octanol into corresponding acid at 90°C. However, other reactants were not selectively transformed into aldehyds or acids because of their oxygen sensivity (alcool-A) or their particular reactivity toward cyclization products (5-Chloro-1-Pentanol). In parallel, H transfer dehydrogenation was developed in anaerobic conditions. Geraniol was choosen as a model molecule since it can be selectively dehydrogenated or isomerizd (a reducible function on the substrate is hydrogenated when alcohol function is dehydrogenated). Some noble metals were evaluated for these reactions (Pd in the presence of alkene as H acceptor or Ag for acceptorless dehydrogenation), but performances and selectivities are quite low. Copper catalysts showed better results, and a lot of supports were evaluated. Selectivity toward dehydrogenation product (citral) is not total when styrene is used as hydrogen acceptor, but the use of another H acceptor (confidential) in the presence of copper supported on modified hydrotalcite catalyst allows selective dehydrogenation of geraniol without isomerization intro citronellal. Without H acceptor, this catalyst leads to selective isomerization of secondary allylic alcohols into saturated ketones (90 % selectivity)Dans la prĂ©sente Ă©tude, la compatibilitĂ© de molĂ©cules polyfonctionnelles a Ă©tĂ© Ă©valuĂ©e en oxydation catalytique aĂ©robie. L'oxydation du gĂ©raniol en citral a Ă©tĂ© rĂ©alisĂ©e dans un mĂ©lange t-BuOH/eau Ă 40°C en prĂ©sence de Pt/C et Pt-Bi/C. A 90°C, l'oxydation sĂ©lective du 8-Chloro-1-Octanol en acide 8-ChlorooctanoĂŻque a Ă©tĂ© rĂ©alisĂ©e. Par contre, d'autres substrats n'ont pas pu ĂȘtre transformĂ©s sĂ©lectivement en aldĂ©hyde ou en acide Ă cause de leur sensibilitĂ© vis-Ă-Vis de l'oxygĂšne (alcool-A) ou de leur rĂ©activitĂ© particuliĂšre (5-Chloro-1-Pentanol qui est cyclisĂ© en produits non dĂ©sirĂ©s). En conditions anaĂ©robies, le transfert d'H alcool / accepteur a Ă©tĂ© dĂ©veloppĂ©, Ă partir du gĂ©raniol (alcool allylique) comme substrat modĂšle : il convient de rĂ©aliser soit la dĂ©shydrogĂ©nation sĂ©lective de sa fonction alcool, soit son isomĂ©risation lorsque la fonction alcool est dĂ©shydrogĂ©nĂ©e en mĂȘme temps que la C=C allylique est hydrogĂ©nĂ©e. Les catalyseurs au Cu supportĂ© ont montrĂ© un potentiel beaucoup plus prometteur que les mĂ©taux nobles, et de nombreux supports ont Ă©tĂ© Ă©valuĂ©s. Le styrĂšne utilisĂ© comme accepteur d'H ne permet pas d'obtenir sĂ©lectivement le produit de dĂ©shydrogĂ©nation du gĂ©raniol (citral), par contre l'utilisation d'un accepteur d'H confidentiel permet d'obtenir sĂ©lectivement le citral sans former de citronellal (produit d'isomĂ©risation de la fonction alcool allylique) en prĂ©sence de catalyseur au cuivre sur un support ex-Hydrotalcite. En l'absence d'accepteur, ce catalyseur permet l'isomĂ©risation sĂ©lective de diffĂ©rents alcools allyliques avec des sĂ©lectivitĂ©s jusqu'Ă 90 % en cĂ©tones saturĂ©e
Catalysts development for hydrogen transfer : application to biobased compounds
Dans la prĂ©sente Ă©tude, la compatibilitĂ© de molĂ©cules polyfonctionnelles a Ă©tĂ© Ă©valuĂ©e en oxydation catalytique aĂ©robie. L'oxydation du gĂ©raniol en citral a Ă©tĂ© rĂ©alisĂ©e dans un mĂ©lange t-BuOH/eau Ă 40°C en prĂ©sence de Pt/C et Pt-Bi/C. A 90°C, l'oxydation sĂ©lective du 8-Chloro-1-Octanol en acide 8-ChlorooctanoĂŻque a Ă©tĂ© rĂ©alisĂ©e. Par contre, d'autres substrats n'ont pas pu ĂȘtre transformĂ©s sĂ©lectivement en aldĂ©hyde ou en acide Ă cause de leur sensibilitĂ© vis-Ă-Vis de l'oxygĂšne (alcool-A) ou de leur rĂ©activitĂ© particuliĂšre (5-Chloro-1-Pentanol qui est cyclisĂ© en produits non dĂ©sirĂ©s). En conditions anaĂ©robies, le transfert d'H alcool / accepteur a Ă©tĂ© dĂ©veloppĂ©, Ă partir du gĂ©raniol (alcool allylique) comme substrat modĂšle : il convient de rĂ©aliser soit la dĂ©shydrogĂ©nation sĂ©lective de sa fonction alcool, soit son isomĂ©risation lorsque la fonction alcool est dĂ©shydrogĂ©nĂ©e en mĂȘme temps que la C=C allylique est hydrogĂ©nĂ©e. Les catalyseurs au Cu supportĂ© ont montrĂ© un potentiel beaucoup plus prometteur que les mĂ©taux nobles, et de nombreux supports ont Ă©tĂ© Ă©valuĂ©s. Le styrĂšne utilisĂ© comme accepteur d'H ne permet pas d'obtenir sĂ©lectivement le produit de dĂ©shydrogĂ©nation du gĂ©raniol (citral), par contre l'utilisation d'un accepteur d'H confidentiel permet d'obtenir sĂ©lectivement le citral sans former de citronellal (produit d'isomĂ©risation de la fonction alcool allylique) en prĂ©sence de catalyseur au cuivre sur un support ex-Hydrotalcite. En l'absence d'accepteur, ce catalyseur permet l'isomĂ©risation sĂ©lective de diffĂ©rents alcools allyliques avec des sĂ©lectivitĂ©s jusqu'Ă 90 % en cĂ©tones saturĂ©esIn this study, we evaluated the compatibility of polyfunctional alcohols with catalytic aerobic oxidation systems. Geraniol dehydrogenation was carried out in mild conditions (t-BuOH / water mixture as solvent, 40°C) in the presence of Pt / C (promoted with Bi to avoid leaching). These catalysts are efficients for the oxidation of 8-Chloro-1-Octanol into corresponding acid at 90°C. However, other reactants were not selectively transformed into aldehyds or acids because of their oxygen sensivity (alcool-A) or their particular reactivity toward cyclization products (5-Chloro-1-Pentanol). In parallel, H transfer dehydrogenation was developed in anaerobic conditions. Geraniol was choosen as a model molecule since it can be selectively dehydrogenated or isomerizd (a reducible function on the substrate is hydrogenated when alcohol function is dehydrogenated). Some noble metals were evaluated for these reactions (Pd in the presence of alkene as H acceptor or Ag for acceptorless dehydrogenation), but performances and selectivities are quite low. Copper catalysts showed better results, and a lot of supports were evaluated. Selectivity toward dehydrogenation product (citral) is not total when styrene is used as hydrogen acceptor, but the use of another H acceptor (confidential) in the presence of copper supported on modified hydrotalcite catalyst allows selective dehydrogenation of geraniol without isomerization intro citronellal. Without H acceptor, this catalyst leads to selective isomerization of secondary allylic alcohols into saturated ketones (90 % selectivity
Catalytic Transfer Dehydrogenation of Geraniol to Geranial Over Palladium and Copper Supported Catalysts
DURAPI â Vers une meilleure connaissance et un accompagnement technique des exploitations apicoles professionnelles : durabilitĂ©, stratĂ©gies de renouvellement du cheptel et consĂ©quences sur le fonctionnement global de lâexploitation
Variability of the production context, colony losses: professional beekeepers have to cope with several environmental and socio-economic issues to ensure the sustainability of their farm. Thus, the DURAPI project aimed at developing a sustainability assessment framework for bee farming operations through a participatory design involving the stakeholders from the beekeeping sector. We also considered the part of the colony and queen replacement strategy, which is central in the colony management: the existing replacement strategies were identified and their possible consequences on the farm sustainability, in particular on the work organisation, were studied. These results allowed us to develop training tools for future beekeepers. This project also provides several support tools for beekeeping advisors.VariabilitĂ© du contexte de production, pertes de colonies dâabeilles : les exploitations apicoles font aujourd'hui face Ă diffĂ©rentes problĂ©matiques environnementales comme socio-Ă©conomiques. Dans ce contexte, le projet DURAPI a visĂ© Ă Ă©laborer un cadre dâĂ©valuation de la durabilitĂ© de ces exploitations, Ă travers une dĂ©marche participative qui a impliquĂ© de nombreux acteurs de la filiĂšre. ParallĂšlement, la place de la gestion du renouvellement des colonies et des reines dans cette durabilitĂ© a Ă©tĂ© considĂ©rĂ©e. Les principales stratĂ©gies de renouvellement du cheptel mises en place dans les exploitations ont ainsi Ă©tĂ© identifiĂ©es afin dâensuite caractĂ©riser leurs consĂ©quences possibles sur cette durabilitĂ© de lâexploitation, notamment en termes de temps et dâorganisation du travail. Ces diffĂ©rents rĂ©sultats ont donnĂ© lieu Ă la crĂ©ation de supports pour les formateurs en apiculture. Les mĂ©thodes dĂ©veloppĂ©es dans le cadre du projet peuvent par ailleurs ĂȘtre mobilisĂ©es pour lâappui aux apiculteurs ou futurs installĂ©s