The roads to Open Access

This schemes shows the different paths available to researchers in order to publish the results of their research in Open Access

Open Access at UNIL - Report on the Open Access survey and vision

Open Access is a vast global movement, started by the Budapest Open Access Initiative of 2002, seeking to give everyone free access to the fruits of research through the development of the Internet. Open Access allows for the opening of documents by two roads: The Gold Road (research freely accessible from the moment of publication) and the Green Road (simultaneous self-archiving of the manuscript in an institutional repository and its opening after an embargo period). Propelled by the National Open Access Strategy (SNOAS), the University of Lausanne (UNIL) has decided to tackle this issue in an active, open and inclusive manner. This report is part of an internal consultation framework whose ultimate goal is to define the future Open Access policy and the associated overall support measures for researchers

L’Open Access à l’UNIL, Sondage Open Access UNIL 2017 - Rapport et Vision

L’Open Access, ou accès ouvert, est un vaste mouvement mondial, lancé par la Budapest Open Access Initiative en 2002, visant à mettre les résultats de la recherche à la disposition de tous grâce au développement de l’Internet. L’Open Access permet l’ouverture de documents par deux voies : la voie dorée (travaux librement accessibles au moment de la publication) et la voie verte (dépôt simultané d'une copie de la publication dans une archive institutionnelle, et son ouverture souvent après un embargo). Propulsée par la stratégie nationale sur l’Open Access, l’UNIL a pris la décision d’aborder cet enjeux d’une façon active, ouverte et inclusive. Le présent rapport s’inscrit dans le cadre d’une consultation interne au sein de l’UNIL ayant pour but ultime de définir les bases de sa future directive Open Access et l'ensemble des mesures de soutien aux chercheurs qui y seront associées

Shape and Size-Tailored Pd Nanocrystals to Study the Structure Sensitivity of 2-Methyl-3-butyn-2-ol Hydrogenation: Effect of the Stabilizing Agent

Uniform Pd nanocrystals of cubic, octahedral and cube-octahedral shapes were synthesized via a solution-phase method using two stabilizers: poly (vinyl pyrrolidone) (PVP) and di-2-ethylhexylsulfoccinate (AOT) and tested in the hydrogenation of 2-methyl-3-butyn-2-ol. The AOT-stabilized Pd nanocrystals were found to be an order of magnitude more active, but less selective than those stabilized by PVP. This could be attributed to a stronger interaction of PVP with surface Pd by adsorbed N-containing groups. The results obtained were rationalized applying a two-site Langmuir-Hinshelwood kinetic model that allowed predicting 3-4nm cubic or octahedral nanocrystals stabilized by AOT as the optimum active phase ensuring the highest production rate of target MB

Rational Design of Pd-Based Catalysts for Selective Alkyne Hydrogenations

Traditionally, the search for active and selective catalysts involved a rather tedious "hit-and-miss" approach in which hundreds, if not thousands catalysts were tested until the optimal substance was identified. With the advancing theoretical understanding of catalysis and the development of computational power, a new era of rational catalyst design is dawning. This approach, grounded on first principles, is based on new advances in synthesis, characterization and modeling with the ultimate aim of predicting the expected behavior of a catalyst based on chemical composition, molecular structure and morphology. The rational design of a catalyst is a complex process which spans across several levels of scale. In this thesis, the pursuit of a rational design for Pd-based catalysts effective in alkyne hydrogenations is presented. A multi-level integrated approach was thus applied ranging from the nano-scale design of the active sites for a specific reaction, taking into account its structure sensitivity, to the micro-scale design of the supported Pd nanoparticles including metal-additive and metal-support interactions as well as mass and heat transfer phenomena. In order to rationally design a catalyst at a nano-scale, i.e. a catalyst's active site, several methodologies have been hitherto applied, such as the study on single crystals or model catalysts. Here we present the use of metal nanoparticles with tuned sizes (5-30 nm) and shapes (cubes, octahedra and cube-octahedra) prepared via colloidal techniques. These nanoparticles can be tested per se and represent a new generation of model catalysts, complementing single crystal studies, which inherently lack the complexity of industrial catalysis. However, metal nanoparticles, especially those prepared in a controlled manner in order to tailor their shape and size, require the use of stabilizing and/or capping agents capable of directing their growth. These substances can mask the true catalytic behavior of the nanoparticles. Thus, it is of great importance to study the interactions of the active phase with the substances that are in close contact with it, in the so-called meso-scaled level of rational catalyst design. Therefore, the effect of the nature of the stabilizing agent on the catalytic response was studied, as well as the promoting effect of some of these substances. Finally, a methodology was developed capable of eliminating organic stabilizing agents from the surface of nanoparticles without compromising their morphological stability. The knowledge gathered in the first two levels can be applied further to reach the microscale rational catalyst design. In this thesis, a final catalyst consisting on well-defined stabilizer-free supported Pd nanoparticles was used in the hydrogenation of acetylene. This deep study of the catalytic behavior of well-defined Pd catalysts throughout several levels of scale and complexity have given us the tools needed to perform a rational catalyst design for alkyne hydrogenations. Depending on the specific reaction, the active phase can be optimized in terms of the desired activity and selectivity and can be tuned even further with the use of specific additives. Finally, the appropriate support also exerts a promoting effect on the nanoparticles and ensures their anchoring in addition to avoiding heat and mass transfer artifacts