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Leistungsoptimierte Lithium-lonen Batterien

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

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.

FP6-SUSTDEV, Risk Mitigation for Earthquakes and Landslides (LESSLOSS)

Earthquake and landslide risk is a public safety issue that requires appropriate mitigation measures and means to protect citizens, property, infrastructure and the built cultural heritage. Mitigating this risk requires integrated and coordinated action that embraces a wide range of organisations and disciplines. For this reason, the LESSLOSS IP is formulated by a large number of European Centres of excellence in earthquake and geotechnical engineering integrating in the traditional fields of engineers and earth scientists some expertise of social scientists, economists, urban planners and information technologists. The LESSLOSS project addresses natural disasters, risk and impact assessment, natural hazard monitoring, mapping and management strategies, improved disaster preparedness and mitigation, development of advanced methods for risk assessment, methods of appraising environmental quality and relevant pre-normative research. In order for the multi-disciplinary S&T ingredients of the project to be tackled in an efficient and productive manner, the research programme has been split into three distinct areas: physical environment, urban areas and infrastructures. For each one of this areas four main types of transversal fields have been identified as fundamental and capable of producing permanent effects on risk mitigation: (i) instrumentation and monitoring, (ii) methods and technologies to reduce vulnerability, (iii) innovative approaches for design/assessment and (iv) disaster scenarios and loss modelling. Within this general framework, specific objectives will be pursued, such as the development of innovative methods and approaches to design and assessment of structures and earth slopes for both short- and long-term implementation, the development of advanced monitoring techniques and devices, and the development, manufacturing and testing of innovative isolating and dissipating seismic devices. Prime Contractor: Universita degli Studi di Pavia; Pavia; Italy.

Schwerpunktprogramm (SPP) 1294: Bereich Infrastruktur - Atmospheric and Earth system research with the 'High Altitude and Long Range Research Aircraft' (HALO), Methods and algorithms for data exploitation of the imaging Fourier transform spectrometer GLORIA-AB on HALO - MaxiFTS -

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.

Mesoscale Ocean Radar Signature Experiments (MORSE)

MORSE was a joint European project, carried out by six partner institutions in France, Great Britain, and Germany. It was financially supported by the Commission of the European Community as a part of the Marine Science and Technology (MAST) program under contract no. MAS3-CT95-0027. The objective of the project was to gain an understanding of the physical processes involved in radar signatures of internal waves using laboratory tank, airborne radar, and satellite imagery. To achieve the ultimate goal, independent numerical models are needed which are capable of predicting radar backscattering for all radar bands, extracting ocean surface characteristics at high spatial resolution, predicting internal wave fields in time and space, and inverting radar signatures into geophysical parameters. Existing models were not sufficiently reliable to produce quantitative results in order to retrieve the three-dimensional structure of the ocean's hydrodynamic processes. Progress in the understanding and mathematical description of different processes and increasing capacity of modern computers opens doors towards much more detailed, comprehensive models. The activities of the Satellite Oceanography group of the University of Hamburg within the framework of MORSE focused on theoretical considerations regarding the hydrodynamic modulation of ocean waves by spatially varying current fields over internal waves and the radar imaging of the resulting roughness variations. This research was based on our advanced radar imaging model which describes the modulation of the complete two-dimensional ocean wave spectrum according to wave-current interaction theory and the backscattered radar signal by a composite surface model. In addition, the Satellite Oceanography group has wide experience regarding the analysis of radar signatures of internal waves. A large number of ERS-1 / ERS-2 SAR images of internal waves in the Strait of Gibraltar and in the Strait of Messina was analyzed. Furthermore, numerical hydrodynamical models were developed, which are capable of describing the generation and propagation of internal tides and their disintegration into internal solitary waves. The MORSE project has provided an opportunity to exploit and extend the knowledge obtained in previous remote sensing projects and to calibrate and validate the corresponding numerical models.

Schwerpunktprogramm (SPP) 1158: Antarctic Research with Comparable Investigations in Arctic Sea Ice Areas; Bereich Infrastruktur - Antarktisforschung mit vergleichenden Untersuchungen in arktischen Eisgebieten, Modelling of deformtion and recrystallisation microstructures in polar ice

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

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.

FP6-SUSTDEV, European Seas Observatory NETwork (ESONET)

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

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

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.

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