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Reactivity of Oxygenated Volatile Organic Compounds (ROVOC): Esters

Das Projekt "Reactivity of Oxygenated Volatile Organic Compounds (ROVOC): Esters" wird vom Umweltbundesamt gefördert und von Universität Wuppertal, Fachgruppe Chemie und Biologie, Arbeitsgruppe Physikalische und Theoretische Chemie durchgeführt. Oxygenated volatile organic compounds (OVOCs) are omnipresent in the atmosphere. Esters (alkyl alkanoates, e.g. RC(O)OR, R = alkyl groups) are an important class of OVOC with both natural and anthropogenic sources. Esters made up of long chain carboxylic acids are the main constituents of animal- and plant-derived waxes and they also occur naturally in fruits and flowers. Various types of esters are used extensively by industry as solvents in chemical processing. The quest for renewable fuels has seen an increase in the use of biodiesel fuels, which typically consist of methyl and ethyl esters of fatty acids. Esters can also be produced in situ in the atmosphere from, for example, the oxidation of ethers. Few measurements of esters in the atmosphere have been made but those measurements, which have been made, confirm the presence of substantial levels of esters in the atmosphere. Investigations on the atmospheric chemistry of esters to date have been limited to temperature dependent studies of the OH radical kinetics of a number of linear and branched alkyl acetates and room temperature studies of the products from the OH radical or Cl-atom initiated oxidation of a few of these acetates. Studies on methylacetate have shown that the product yield distribution is very temperature dependent. Although this limited set of data has been used been used to improve the structure-activity relationship (SAR) for alkyl esters at 298 K it is clear that there is a definite need for further refine of the SAR for esters particularly with respect to temperature dependence. The project has the overall aim of improving the kinetic, product and mechanistic database for the reactions of OH radicals with a variety of esters as a function of temperature over the range 225-372 K and will use this information to further develop and refine the SAR for esters. The project will consist of the following components: - determination of OH rate coefficients using absolute and relative methods as a function of temperature; - determination of the products of the reactions as a function of temperature and O2 partial pressure; - construction of explicit and simplified reaction mechanisms for models; - development of SAR for a wider range of ester types applicable over the temperature range 225-372 K.

Analysis and Harmonisation (PROFOR)": Mitarbeit in den Arbeitsgruppen 1 und 3 sowie Koordination zweier Unterarbeitsgruppen zur Geschichte von Waldschutzgebieten und zum Konzept der Naturnähe

Das Projekt "Analysis and Harmonisation (PROFOR)": Mitarbeit in den Arbeitsgruppen 1 und 3 sowie Koordination zweier Unterarbeitsgruppen zur Geschichte von Waldschutzgebieten und zum Konzept der Naturnähe" wird vom Umweltbundesamt gefördert und von Universität Göttingen, Burckhardt-Institut, Professur für Naturschutz und Landschaftspflege durchgeführt. In 2002 the COST Action E27 'Protected Forest Areas in Europe - Analysis and Harmonisation' was launched to provide a better understanding of national and international distinctions of Protected Forest Areas (PFAs). With the aim to analyse and harmonise the wide range of PFA categories used in European countries within the context of existing international systems of Protected Areas, until 2006 about 100 researchers and experts from multiple disciplines, representing 25 European countries (see figure below), worked together in three Working Groups, organised as follows: WG 1 'Description and analysis of Protected Forest Areas - national dimension', WG 2 'Harmonisation and improvement of information on European Protected Forest Areas - international dimension', WG 3 'A clearing house mechanism for European Protected Forest Areas'.Working Group 1, in which R. Bürger-Arndt and J. Welzholz represented Germany, described the different sorts of PFAs that exist in the COST Action E27 countries, reviewed their current state and historical development and provided an understanding of what the differences are between them and why. The information gathered in this process was used for a thorough description and analysis of PFAs in Europe, helped Working Group 2 to formulate recommendations for the enhancement of the quality and clarity of information on PFAs at the European level and is intended to be a source of information for scientists, foresters, policy makers and conservationists at the national and international level.The achievements of Working Group 1 were mainly made available by two project publications and two project homepages. The country reports (LATHAM et al. 2005) supply a detailed description of national Protected Area types with their historical and socio-economic background, including information on the historical development of PFAs, responsible organisations, selection criteria and representativity, inventories and monitoring and wider landscape issues. In conjunction with the elaboration of the PFA country reports, national PFA tables were compiled. They contain summary statistics on area, size, ownership, motivations for protection and management restrictions. Summarising and comparing synthesis reports on the examined issues are part of the final report of the COST Action E27 (FRANK et al. 2007). Two homepages built up by Working Group 3 provide several documents and interactive databases on PFAs produced in the course of the COST Action E27.

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