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Leistungsoptimierte Lithium-lonen Batterien

Das Projekt "Leistungsoptimierte Lithium-lonen Batterien" wird vom Umweltbundesamt gefördert und von Technische Hochschule Aachen, Lehrstuhl und Institut für Stromrichtertechnik und Elektrische Antriebe durchgeführt. Der schnelle Fortschritt der elektronischen Geräte erhöht die Nachfrage nach verbesserten Li-Ionen Batterien. Kommerziell erhältliche Li-Zellen nutzen meist Lithiumkobaltoxid für die positive Elektrode. Doch gerade dieses Material ist ein Hindernis für eine weitere Optimierung, insbesondere für eine Kostensenkung. Vor allem für größere Anwendungen wie Hybrid- oder Elektrofahrzeuge müssen alternative Materialen erforscht werden, die billiger, sicherer und umweltverträglicher sind. Daher wird im ISEA derzeit ein neues Forschungsprojekt ins Leben gerufen und die dafür benötigte Infrastruktur geschaffen. Die Forschung wird sich auf die Untersuchung geeigneter Übergangsmetalloxide und Polyanionen konzentrieren, die besonders gut zur Einlagerung von Li-Ionen geeignet sind. Es werden neue Herstellungsverfahren unter Verwendung wässriger Precurser-Substanzen untersucht, die Verbindungen mit überlegenen Eigenschaften erzeugen und außerdem leicht an eine Massenproduktion angepasst werden können. Ziel der Arbeiten ist, preisgünstiges Elektrodenmaterial zu entwickeln, das eine spezifische Energie von über 200 Wh/kg und eine Leistungsdichte von 400 W/kg aufweist. Außerdem werden Arbeiten im Bereich der physikalisch-chemischen Charakterisierung der neuen Materialien stattfinden sowie elektrochemische Analysen der gesamten Zellen- und Batteriesysteme durchgeführt. Das elektrodynamische Verhalten der neuen Zellen wird u. a. mit Hilfe der elektrochemischen Impedanzspektroskopie analysiert, um präzise und zuverlässige Algorithmen für ein späteres Batteriemonitoring im realen Betrieb zu finden.

Ein neuartiger Retrievalansatz zur Ableitung troposphärischer Temperatur- und Feuchteprofile unter allen Wetterbedingungen für eine verbesserte Quantifizierung von Verdunstungsraten

Das Projekt "Ein neuartiger Retrievalansatz zur Ableitung troposphärischer Temperatur- und Feuchteprofile unter allen Wetterbedingungen für eine verbesserte Quantifizierung von Verdunstungsraten" wird vom Umweltbundesamt gefördert und von Universität Leipzig, Fakultät für Physik und Geowissenschaften durchgeführt. Die ständige Weiterentwicklung und Verbesserung der Wetter- und Klimamodelle stellt die Fernerkundung der Atmosphäre vor große Herausforderungen. Für die Evaluierung der Modelle werden immer besser aufgelöste Messungen und Methoden benötigt. Herkömmliche Ansätze scheitern hier vor allem an fehlenden kontinuierlichen Beobachtungen der Temperatur und Feuchte bei allen Wetterbedingungen und insbesondere bei Regen. Ein Windprofiler ist allerdings auch bei solchen Bedingungen in der Lage Vertikalinformationen der Temperatur- und Feuchtegradienten zu messen. Der hier vorgeschlagene neuartige Ansatz aus einer Synergie aus Windprofiler (inklusive Radio Acoustic Sounding System), Ramanlidar, Mikrowellenradiometer und Wolkenradar ermöglicht eine automatisierte und kontinuierliche Erstellung von Temperatur- und Feuchteprofilen sogar bei Niederschlägen. Die zu verwendende variationelle Methode (optimale Schätzung, in engl. â€Ìoptimal estimationâ€Ì) bietet dabei ein robustes Hilfsmittel für die Kombination mehrerer Messgeräte unter Einbeziehung der Unsicherheiten der einzelnen Systeme. Bei der optimalen Schätzung wird ein vorgegebener Anfangszustand (z.B. die Klimatologie des Standorts oder der letzte bekannte Zustand) so lange iterativ variiert, bis er mit den Beobachtungen der verschiedenen Messgeräte innerhalb der Unsicherheiten übereinstimmt. Die Methode ermöglicht auch eine ausführliche Analyse der Unsicherheiten der Resultate und eine Einschätzung der Beiträge der einzelnen Geräte.Die langen Zeitreihen an Daten und die Kombination an sich ergänzenden Messinstrumenten, insbesondere mit dem 482 MHz Windprofiler am Meteorologischen Observatorium Lindenberg â€Ì Richard Aßmann Observatorium (MOL-RAO), sind einzigartig. Der Antragsteller kann hier seine umfangreichen Erfahrungen mit Instrumentensynergie und der Entwicklung von Algorithmen zur Ableitung atmosphärischer Variablen einbringen, um eine kontinuierliche Zeitreihe von Temperatur- und Feuchteprofilen mit bisher nicht erreichter Genauigkeit innerhalb und oberhalb von Wolken und insbesondere bei Niederschlag zu erstellen. Die thermodynamischen Profile bieten die ideale Möglichkeit, die Verdunstungsraten und die daraus resultierende Abkühlung mit einer verbesserten Genauigkeit zu quantifizieren. Die Unsicherheiten, die durch ungenaue Profile der relativen Feuchte und Temperatur entstehen, werden mit Hilfe von Simulationen abgeschätzt. Langzeitbeobachtungen an MOL-RAO werden genutzt, um aussagekräfige Statistiken über die Verdunstungs- und Abkühlungsraten zu erstellen. Die Ergebnisse werden für verschiedene Bedingungen wie stratiformen und konvektiven Niederschlag und für verschiedenen Jahreszeiten evaluiert. Dies wird den Modellieren helfen, die Parametrisierungen der Verdunstungsraten in kleinskaligen Modellen zu evaluieren.

Methods and algorithms for data exploitation of the imaging Fourier transform spectrometer GLORIA-AB on HALO - MaxiFTS -

Das Projekt "Methods and algorithms for data exploitation of the imaging Fourier transform spectrometer GLORIA-AB on HALO - MaxiFTS -" wird vom Umweltbundesamt gefördert und von Karlsruher Institut für Technologie (KIT), Institut für Meteorologie und Klimaforschung - Atmosphärische Spurenstoffe und Fernerkundung durchgeführt. GLORIA combines a Michelson interferometer with a detector array of 128 x 128 pixels and will be the first 2D infrared limb imaging spectrometer worldwide. It is designed for HALO and will measure the distribution of temperature and a considerable number of trace constituents along with cloud mapping with unprecedented spatial resolution in the free troposphere and lower stratosphere. It is an essential contribution to the HALO demo missions TACTS, POLSTRACC, and CIRRUS-RS. Imaging Fourier transform spectrometers impose a number of challenges with respect to instrument calibration / characterisation and for algorithm development. The work of the first proposal focused on characterisation and modeling of the instrument and on the development of methods and algorithms which are capable of generating calibrated spectra with high accuracy. Accurately calibrated spectra are a prerequisite for the retrieval of atmospheric parameters and the scientific data exploitation. Within this renewal proposal the developed characterisation methods will be applied to the instrument in flight configuration, and the new algorithms will be used to generate highly accurate calibrated spectra from the raw interferograms measured during the HALO demo missions. The work will be completed by a thorough error analysis for the calibrated spectra. Finally, instrument settings, calibration scenario and data processing shall be optimised with respect to data quality. This proposal contributes to the development of high technology sensors and instruments for the use on HALO.

Modelling of deformtion and recrystallisation microstructures in polar ice

Das Projekt "Modelling of deformtion and recrystallisation microstructures in polar ice" wird vom Umweltbundesamt gefördert und von Universität Tübingen, Geographisches Institut durchgeführt. Knowledge of the deformation mechanisms of polar ice is of crucial importance to predict the flow of polar ice caps and hence their influence on the global climate. Deformation of ice also impacts on one of the best climate record on Earth: the individual ice layers observed in deep ice cores. Microstructures form the main record of in situ deformation, by revealing the deformation processes that operate during the flow of an ice sheet. New microstructural analysis techniques developed at AWI now allow a much more detailed and extensive assessment of these microstructures than ever before. Within this project, a start has been made with the numerical modelling of ice microstructures, using the comprehensive modelling platform Elle. After updating and refining algorithms, Elle is now capable of simulating several of the main processes that occur in polar ice: recrystallisation, grain growth and crystal-plastic deformation. In the course of the project s remaining 26 months1 existing routines for two-phase materials will be adapted to model ice with bubbles or clathrates, and to model intracrystalline recovery. Results of systematic simulations will be compared quantitatively with theoretical analyses and the unique microstructure dataset available at AWI of several firn and ice cores (especially the EPICA-DML deep ice core). In particular we will critically reassess the role of grain boundary formation and migration that continually reworks the microstructure. The results of this project will improve our knowledge of the mechanical behavior of polar ice and refine the analysis of climatic records, which are essential to ice sheet and climate modelling.

Investigation of aerosol particle hygroscopicity and their cloud forming potential in the supercooled temperature range

Das Projekt "Investigation of aerosol particle hygroscopicity and their cloud forming potential in the supercooled temperature range" wird vom Umweltbundesamt gefördert und von Leibniz-Institut für Troposphärenforschung e.V. durchgeführt. This project aims at a) the development of new instrumentation for the expansion of the experimental temperature range of aerosol particle activation and hygroscopic growth measurements down to low, but atmospheric relevant temperatures (-25°C ? T ? 0°C), b) the subsequent analysis of hygroscopic growth and activation behavior of inorganic and organic particles in this temperature range, and c) the determination of an effective hygroscopicity parameter for these compounds for temperatures below 0°C. These goals will be achieved via development and application of a novel Hygroscopicity Tandem Differential Mobility Analyzer (LT-HTDMA) capable of measuring hygroscopic particle growth at temperatures below the melting point of water and the application of the Leipzig Aerosol Cloud Interaction Simulator (LACIS) for the activation measurements below 0°C. The experiments will be accompanied by model simulations describing the coupled fluid and particle dynamical processes taking place inside LACIS which are necessary for data interpretation. The experimental results of growth and activation measurements will be tested against existing Köhler models with the goal of verifying and / or expanding existing effective hygroscopicity parameterizations to temperatures below 0°C. This combination of experimental and theoretical methods will significantly contribute to improving the understanding of the cloud forming processes in the mid-latitudes.

European Seas Observatory NETwork (ESONET)

Das Projekt "European Seas Observatory NETwork (ESONET)" wird vom Umweltbundesamt gefördert und von IFM-GEOMAR Leibniz-Institut für Meereswissenschaften durchgeführt. The aim of ESONET is to create an organisation capable of implementing, operating and maintaining a network of ocean observatories in deep waters around Europe from the Arctic Ocean to the Black Sea connected to shore with data and power links via fibre optic cables. The fundamental scientific objective is to make continuous real-time observations of environmental variables over decadal, annual, seasonal, diel and tidal time scales. Constant vigilance will allow resolution of quasi-instantaneous hazardous events such as slides, earthquakes, tsunamis and benthic storms. ESONET will form a sub sea segment of the GMES (Global Monitoring for Environment and Security) with sensors extending from the sub sea floor, through the water column to sub-surface sensors providing calibration of satellite borne sensors. ESONET brings together leading oceanographic and geosciences institutes in Europe together with universities, industry and regional agencies. It will provide integration across disciplines from geosciences, through physical, chemical and biological oceanography to technologies of instrumentation, cables, data processing and archiving. Jointly executed research will demonstrate functioning observatories at several cabled and non-cabled sites around Europe. Existing deep-sea cables installed for neutrino telescopes will be utilised in the Mediterranean sea and shallower tests sites will be established elsewhere. Principles of sensor management, calibration, metadata and data quality will be established with real-time dissemination and generation of hazard warning. ESONET will run a training and education program through courses, scholarships, exchange of personnel between participating institutes, and outreach to the general public. Dissemination will also include a web portal, with links to the INSPIRE Geo-Portal, and with all sub sea observatory projects worldwide, enabling the widest possible access to information. Prime Contractor: Institut Francais de Recherche pour l'Exploitation de la Mer; Issy-les-Moulineaux; France.

Characterization of different compacted wheel tracks by means of microbial properties in a forested site

Das Projekt "Characterization of different compacted wheel tracks by means of microbial properties in a forested site" wird vom Umweltbundesamt gefördert und von Eidgenössische Forschungsanstalt für Wald, Schnee und Landschaft durchgeführt. Soil compaction caused by passage of logging machinery reduces the soil air capacity. Changed abiotic factors might induce a change in the soil microbial community and favour organisms capable of tolerating anoxic conditions. Aerated soils that are shifted to anoxia can produce the greenhouse gases methane and N2O. For example, methanogenesis is the dominating electron-accepting process during the anaerobic oxidation of organic matter. Thus, the prolonged compaction of forest soils might enhance greenhouse gas-producing microbial activities and lead to a gradual, quantitative shift in the occurrence and activities of associated prokaryotes. This shift might be of general importance, because heavy machinery is increasingly used for logging activities. Aims: The goals of this study were to resolve differences between soil microbial communities obtained from wheel-tracks (i.e. compacted) and their adjacent undisturbed sites, and to evaluate differences in potential anaerobic microbial activities of these contrasting soils. Special emphasis will be given to organisms which are responsible for the production of greenhouse gases (nitrous oxide, methane) after soil compaction. Methods: Characterization of microbial communities with molecular tools (T-RFLP fingerprinting, DGGE, cloning and sequencing); Quantification of functional genes (quantitative PCR); Soil Microbial Measurements (C-mineralization, respiration, microbial biomass C).

Effectiveness of surveillance, prevention and control strategies of avian influenza

Das Projekt "Effectiveness of surveillance, prevention and control strategies of avian influenza" wird vom Umweltbundesamt gefördert und von Bundesamt für Lebensmittelsicherheit und Veterinärwesen BLV durchgeführt. The spread of highly pathogenic avian influenza (HPAI) is a global threat to all countries with a poultry industry, semi-commercial production and backyard poultry and has already caused enormous economic losses. Since 1997, H5N1 viruses which have infected humans have included Haemagglutinins from several clades and variable genotypes. Therefore, all HPAI H5N1 viruses must be considered a potential threat to public health. This increases the scope of viruses with pandemic potential and the importance of continued surveillance of H5N1 avian influenza outbreaks. WHO and the OIE are urging countries worldwide to initiate surveillance programmes tailored to an early detection of cases of HPAI. There is an international demand to reduce random sampling and redirect the scarce resources to a targeted sampling, which focuses on the high-risk population, which is even more true for developing countries e.g. in Africa, which are almost devoid of surveillance capacity. In these cases, risk-based surveillance, and aiming at the most probable source of disease to save scarce resources are even more justified. This project aims: 1) To develop a statistical risk based framework for the combined analysis of surveillance data on avian influenza virus originating from various sources. 2) To develop a model for the assessment and optimisation of the effectiveness of different surveillance strategies for avian influenza. 3) To develop models to assess the effectiveness of different control strategies to prevent infection and spread of HPAI in commercial poultry. The approach is based on the Swiss Tropical Institute's competence in Bayesian spatial risk analyses, transmission modelling of vector borne and zoonotic diseases and its international network in Africa and Asia. This project will focus on Switzerland but within the global context of transport, trade and wild bird migration. It will collaborate with all involved institutions in Switzerland dealing with domestic poultry and wild birds. Expected results and innovations are: 1. Risk maps and contributions to risk maps for LPAI and HPAI on wild and domestic birds in Switzerland. 2. Decision tree for AI risk based surveillance in Switzerland applicable also to low income countries. 3. Risk based surveillance map and sampling plan for AI in Switzerland. 4. Performance indicators of surveillance sensitivity and cost-effectiveness of surveillance of AI in Switzerland and 5. A transmission model of HPAI adapted to Switzerland capable to simulate different intervention strategies.

Extensive Production Systems in Semi-Arid Regions - Options for Sustainable Future Livelihoods (TPP 6; NCCR North South)

Das Projekt "Extensive Production Systems in Semi-Arid Regions - Options for Sustainable Future Livelihoods (TPP 6; NCCR North South)" wird vom Umweltbundesamt gefördert und von Institute of Sahel durchgeführt. Extensive production systems (EPS) are effective land use systems which allow using scarce natural resources in vast rural semi-arid and highland-lowland areas in a sustainable way by various societies. However, the societal and economic role of EPS is frequently underestimated if not overlooked, particularly at national political level. Ranging from pastoralism (sedentary and mobile) to alternative land uses (e.g. agro-sylvo-pastoralism), which secure the livelihoods of millions of rural peoples; the diversity of adaptation is remarkable. Over the last decades rapid and major socio-political, economic, cultural, institutional, and ecologic changes have put heavy and unprecedented pressures on many EPS. Considering their economic and political marginalisation, innovations are needed to motivate the younger generation to reconsider the EPS areas as a promising way of life and to convince policy makers to consider EPS as a potential capable to contribute to reduce migration towards urban centres. Though the scientific literature regarding key features, potentials, and alternative land use systems is vast, few rigorous scientific comparative investigation related to implementation processes has been conducted so far. To fill this gap, such research should (i) link sociological, ecological, and economic perspectives, (ii) follow an inter- and trans-disciplinary approach grounded in regional partnerships, and (iii) compare and capitalize experiences gained in different geographical contexts. Moreover, the current situation should be reassessed by applying modern technologies while developing and promoting simple but well standardised and adapted (impact) monitoring protocols. The research gap identified and intended to be addressed corresponds to two major strengths of the NCCR, which are (i) a strong focus on inter- and trans-disciplinary research and learning processes, and (ii) the opportunity to compare potentials, options, and best practices in the different JACS regions. The TPP is designed to build on these strengths in order to make a genuine contribution to research on EPS. Moreover, it draws upon a systemic approach allowing tackling the complexity of the issue. Two entry points for the selection and implementation of promising alternatives and options are proposed: (i) access to social services and (ii) sustainable natural resource management. These two entry points are chosen according to the existing research priorities in the JACS WAF and CAS. This will allow extending the current achievements in the different regions by broadening the perspective towards a more comprehensive understanding of implementation, e.g. of novel land use arrangements (pastoral code, new collective institutions) or adapted social and economic services (e.g. joint animal and human vaccinations, commodity chains). (abridged text)

Minimization of and adaptation to climate change: Impacts on biodiversity (MACIS)

Das Projekt "Minimization of and adaptation to climate change: Impacts on biodiversity (MACIS)" wird vom Umweltbundesamt gefördert und von Helmholtz-Zentrum für Umweltforschung GmbH - UFZ, Department Biozönoseforschung durchgeführt. MACIS will review and meta-analyse the existing projections of climate change impacts on biodiversity. It will assess the available options to prevent and minimise negative impacts for the EU25 up to 2050 and review the state-of-the-art on methods to assess the probable future impacts of climate change on biodiversity. This includes the review of possible climate change adaptation and mitigation measures and their potential effect on future biodiversity. MACIS wants to further develop a series of biodiversity and habitat models that address biodiversity impacts, and are capable of calculating the consequences of the changes in the trends in drivers as specified by the narrative scenarios provided by the IPCC. MACIS will identify policy options at EU, MS, regional and local levels to prevent and minimise negative impacts from climate change and from climate change adaptation and mitigation measures.

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