34 research outputs found

    Proceedings of the DGMK-conference 'Synthesis gas chemistry' Authors' manuscripts

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    The main topics of the DGMK-Conference ''Synthesis Gas Chemistry'' were: production of synthesis gas from several educts, new catalysts, Fischer-Tropsch synthesis, hydroformylation, steam reforming and carbonylationAvailable from TIB Hannover: RN 4117(0003) / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekSIGLEDEGerman

    Catalytic Isofunctional Reactions—Expanding the Repertoire of Shuttle and Metathesis Reactions

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    Transfer hydrogenation, alkene metathesis, and alkyne metathesis possess great value to the synthetic chemistry community. One of the key features of these processes is their reversibility, which can be attributed to the presence of the same number and type of functional groups in both the reactants and products, making these reactions isofunctional. These classic reactions have recently inspired the development of novel shuttle and metathesis reactions that offer great promise for synthetic chemistry. This Review describes and systematically categorizes both recent and older examples of shuttle and metathesis reactions other than transfer hydrogenation and alkene/alkyne metathesis

    Environmental conditions shape the chemical signal design of lizards

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    The signals that animals use to communicate often differ considerably among species. Part of this variation in signal design may derive from differential natural selection on signal efficacy; the ability of the signal to travel efficiently through the environment and attract the receiver's attention. For the visual and acoustic modalities, the effect of the physical environment on signal efficacy is a well-studied selective force. Still, very little is known on its impact on chemical signals. Here, we took a broad, phylogenetic comparative approach to test for a relationship between animals' signal chemistry and properties of their natural environment. Our study focused on lizards from the Lacertidae family. We sampled 64 species across three continents and determined the lipophilic composition of their glandular signalling secretions using gas chromatography–mass spectrometry. For each species, an array of environmental variables of high temporal and spatial resolution was obtained from climate databases. Species varied considerably in the overall richness (number of constituents) of their secretions, as well as in the relative contribution of the major chemical compound classes. Signal richness and the relative contribution of the respective compounds exhibited little evidence of phylogenetic relatedness, suggesting that chemical signals may change very rapidly. Neither insularity nor substrate use affected chemical signal composition, however, we found a strong statistical relationship between the chemistry of the lizards' secretions and aspects of the thermal and hydric environment they inhabit. Species from ‘xeric’ milieus contained high proportions of stable fatty acid esters and high molecular weight alcohols in their glandular secretions, which likely increase the persistence of secretion scent-marks. In contrast, species inhabiting ‘mesic’ environments produced secretions of a high chemical richness comprising high levels of aldehydes and low molecular weight alcohols. This chemical mix probably creates a volatile-rich signal that can be used for long-distance airborne communication. We argue that the observed variation in signal design results from differential natural selection, optimizing signal efficacy under contrasting environmental conditions.inancial support to JM and RGR was provided by the Spanish's Ministerio de Economía y Competitividad projects MICIIN‐CGL2011‐24150/BOS and MINECO CGL2014‐53523‐P. RGR is indebted to the Spanish Ministerio de Economía y Competitividad (FPI predoctoral grant number BES‐2012‐054387). This work was part of SB's doctoral thesis at the University of Antwerp, and made possible through financial support from the University of Antwerp.Peer Reviewe
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