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VP-3.2./BioWPC

Das Projekt "VP-3.2./BioWPC" wird vom Umweltbundesamt gefördert und von 3-P Präzisions-Plastic-Produkte GmbH durchgeführt. Die Weiterverarbeitung der innovativen Holz-Polymer-Werkstoffe zu Bauteilen im Spritzgießverfahren ist das Ziel in diesem Teilvorhaben. Im Mittelpunkt stehen die Ermittlung und die Verarbeitbarkeit der neuen Materialien und die Optimierung des Spritzgießverfahrens. So sind der Einzug und die Schneckengeometrie der Spritzgießautomaten an die Materialien anzupassen. Die Anspritzsysteme müssen für den Erhalt der Naturfasergeometrien hinsichtlich des Querschnitts scheroptimiert werden. Um die Scherbelastung so gering wie möglich zu halten, müssen die Werkzeuge auf die neuen Materialien ausgelegt sein. Die Parameter sollen an entsprechenden Prüfwerkzeugen ermittelt werden. Um den komplexen Bauteilen einen ästhetischen Mehrwert zu geben, soll die farbliche Direktgestaltung und die Oberflächenstrukturierung im Spritzgießprozess untersucht werden. Die Bauteile sollen als Demonstrationsobjekte für die Leistungsfähigkeit des neuen Werkstoffes dienen. AP1 Evaluierung der Verarbeitungsmöglichkeiten mittels Spritzgießtechnik an ReferenzsystemenAP2 Bauteilauslegung und Entwurf von Spritzgießkavität sowie deren FertigungAP3 Erforschen des Verarbeitungsverhaltens in Abhängigkeit der Rezeptur der KompositeAP4 Anpassen und Optimieren der Spritzgießtechnik für die Verarbeitung der BioWPCAP5 Untersuchung der optischen Direktgestaltung im SpritzgießprozessAP6 Bewerten & Erproben der Verfahrensabläufe und der Prozessstabilität im Demonstrationsmaßstab über die Herstellung von Demonstratorbauteilen.

PV-H2-Boot Solgenia

Das Projekt "PV-H2-Boot Solgenia" wird vom Umweltbundesamt gefördert und von Hochschule Konstanz Technik, Wirtschaft und Gestaltung, HTGW, Institut für Angewandte Forschung , Energiewandlung in Solarsystemen (IAF,EWIS) durchgeführt. 1. Introduction: In view of the increasing problem of energy supply, the University of Applied Sciences Konstanz developed a research boat powered by photovoltaic and fuel cells. The core question of the research project is, if such a combination represents a viable option for recreational and commercial boating. To answer this question, long-time performance-studies of each component by itself and in combination with others in marine environment are necessary. An Information-Management-System (IMS) interfacing to about ninety parameters was developed, providing the basis for analysis. 2. Energy Supply System: The energy supply system consists of two energy conversion units (PV-generator and fuel cell) and two energy storage units (battery and hydrogen tank). A DC/AC-inverter together with an asynchronous motor converts the electrical energy into mechanical energy for the propeller. The voltages between the three fuel cell modules as well as the PV-generator and the battery are adjusted by DC/DC-converters (see figure 1). The hydrogen will be provided by an electrolysis unit within the laboratory driven by a PV-generator and stored on land. One of the research aims is to adapt the hydrogen production depending on solar radiation to the hydrogen demand by the stationary fuel cells (in the laboratory) and the mobile fuel cells (in the boat). 3. Information management system (IMS): The requirements which the IMS has to fulfil are quite complex: 1. a real-time control-system has to operate the boat and process the parameters, 2. a graphical user interface has to provide meaningful and clear information for skipper as well as service and scientist, 3.measured data has to be periodically transmitted to a data bank at the institute for further processing. Use of the Internet gives independence of location. 4. Energy management: Energy management is one of the main tasks of the IMS. One of the research aims is to develop and optimize the management rules. The energy system itself consists of one controllable (fuel cell) and one not controllable energy converter (PV-generator) as well as of two energy storage devices (battery and H2-tank). Parameters affecting the energy management are among others: speed of boat, distance to travel, battery capacity and solar radiation. These parameters are either measured directly or calculated by the IMS. The Solgenia additionally will be used as laboratory unit in teaching: The students shall become familiar with the fundamental problems of managing renewable energies. 5. Graphical user interface: An industrial touch panel PC serves as man-machine-interface. The graphical user interface was divided into two basic groups: skipper and service/scientist. The menu for the latter group was protected by password to prevent an inexperienced skipper from creating any mischief. etc.

Element cycles in mountain regions under various land use

Das Projekt "Element cycles in mountain regions under various land use" wird vom Umweltbundesamt gefördert und von Universität Bayreuth, Fachgruppe Geowissenschaften, Bayreuther Zentrum für Ökologie und Umweltforschung (BayCEER), Lehrstuhl für Agrarökosystemforschung durchgeführt. Research question: What is the role of agricultural land use in changes of nutrient cycles and losses dependingon surface slope and climate? Approach: Annual balance of main nutrients for 3-4 main agricultural farms based on fertilizer input, partitioning of nutrients in above and below ground plant parts, output with harvest, losses with DOM and erosion (in collaboration with other TP). The balances will be done depending on agricultural practices in Eger and Haean Catchment and will be compared with adjacent grassland and forest. Obtained element cycles will be upscaled from farm area to the level of both catchments basins depending on specific land use, surface slope and climate. Research question: Can we reconstruct previous erosion and nutrient losses and separate them under forest and under agricultural use? Approach: Undisturbed sediment cores (7 for Eger and 7 for Haean) will be taken from the lakes and soils of landscapes subordinated to agricultural fields. Three radiocarbon data of wood particles at increasing depth for each sediment core will be used as references. The age of the bottom sediment layer should be less than 1000 years. The total content of C, N, P, K, Mg, Ca, Si will be analyzed in individual laminae or sediment layers. Conclusions will be drawn based on the thickness of the laminae, their elements content and the ratio between nutrients and Si. The conclusions will be proven by 13C (vegetation change) and 15N (N input by fertilizers) of individual laminae. Research question: What are the best management practices for sloping uplands? Approach: Measured element cycles and losses under various agriculture practice will be analysed and practices with the least nutrient losses and erosion will be selected. The best management practices for landscapes with different slopes will be elaborated.

F+E eines Oelschoepf-Verfahrens zur Bekaempfung von Meeres-Oel-Verschmutzung nach Jastram-Waas - Phase 3

Das Projekt "F+E eines Oelschoepf-Verfahrens zur Bekaempfung von Meeres-Oel-Verschmutzung nach Jastram-Waas - Phase 3" wird vom Umweltbundesamt gefördert und von Jastram-Werke durchgeführt. Im Rahmen dieses Vorhabens wird ein neues Verfahren entwickelt und funktionsfaehig erprobt, mit dessen Hilfe es moeglich ist, grosse Oelverschmutzungen, die nach einem Unfall auf hoher See entstanden sind, aufzunehmen und so vom Wasser zu trennen, dass nahezu reines Oel gelagert werden kann. Das gesamte System besteht aus einem 'Dynamischen Vorwehr', mit dem ein Aufstauen des meist sehr duennen Oelfilms bewirkt wird; ausserdem ermoeglicht es hoehere Fahrgeschwindigkeiten des Aufnahmegeraetes. Die Seegangsbewegungen vor dem Geraet werden mit Hilfe einer 'Trennschicht-Niveau-Messsonde' ermittelt und ueber eine elektronische Regelstrecke sowie eine Hochdruck-Hydraulikanlage an einen 'Verschlussschieber' weitergegeben. Dieser Schieber faehrt so hinter einer Oeffnung auf- und abwaerts, dass nur die oberste Fluessigkeitsschicht, - also im wesentlichen das Oel - in das Fahrzeuginnere hineinfliessen kann. Von dort gelangt das Gemisch in eine 'Separationsanlage', aus der das Wasser mit einem Restoelgehalt von ca. 500 ppm ausgeschieden wird. Die Arbeit zielt auf zwei Systeme: eines fuer 'grosse Raeumleistungen' - z.B. ein quertraversierendes Schiff, dessen Laengsseite mit mehreren derartigen Oeffnungen versehen ist. Das andere System ist fuer 'schnelle Einsatzbereitschaften' praedestiniert. Es ist eine 'Barge', die in kuerzester Zeit an den Unfallort gebracht werden kann und dort auf kleinem Raum relativ grosse Mengen Oel aufstaut, abschoepft und separiert.

2nd Workshop on Fats and Oils as Renewable Feedstock for the Chemical Industry

Das Projekt "2nd Workshop on Fats and Oils as Renewable Feedstock for the Chemical Industry" wird vom Umweltbundesamt gefördert und von abiosus Gemeinnütziger Verein zur Förderung der Forschung über nachwachsende Rohstoffe e.V. durchgeführt. Internationale wissenschaftliche Diskussion und Gedankenaustausch der neuesten Ergebnisse auf dem Gebiet der chemischen Nutzung von Fetten und Ölen. Die wichtigsten Gruppen, die weltweit auf dem Gebiet 'Fats and Oils as Renewable Feedstocks fort he Chemical Industry' arbeiten, werden zur wissenschaftlichen Diskussion ihrer neuesten Ergebnisse und der Möglichkeiten der Anwendung neuer, insbesondere katalytischer Reaktionen auf Öle und Fette zu dem internationalen Workshop an der FH OOW in Emden eingeladen. Der Workshop dient auch dazu, die Nachwuchsgruppe 'Stoffliche Nutzung von Fetten und Ölen als nachwachsende Rohstoffe: Synthese von Zwischenprodukten der chemischen Industrie' als Zentrum der internationalen Diskussion zu diesem Thema etablieren. Die Nachwuchsgruppe an der FH OOW kann bei dem Workshop ihre bereits bestehenden Kontakte mit führenden Experten auf ihrem Forschungsgebiet weiterentwickeln und neue Kontakte knüpfen sowie diese für ihre Arbeit nutzen. Die Ergebnisse des Workshops werden in einem Special Issue des European Journal of Lipid Science and Technology publiziert.

Teilprojekt 2: Akustik

Das Projekt "Teilprojekt 2: Akustik" wird vom Umweltbundesamt gefördert und von Stiftung Alfred-Wegener-Institut für Polar- und Meeresforschung e.V. in der Helmholtz-Gemeinschaft (AWI) durchgeführt. Diel vertical migration and geographical distribution of our target organism krill (Euphausia superba, E. crystallorophias) but also other species e.g. myctophids, copepods (Calanus propinquus, Rhincalanus gigas), and other zooplankter (salps, pteropods, chaetognaths, amphipods) are detected by means of a four-split beam acoustic array (38, 72, 120, 200 kHz). Our major questions are: Do organisms migrate daily in relation to the light field, feeding conditions and/or to the predator field? Do populations of different species and/or different developmental stages of one species segregate in certain environmental conditions or different times of the year? How does the ocean current system influence the geographical distribution of zooplankton or krill populations? Is the geographical distribution of species subject to change and if so, what are the possible causes?

Plant-soil interactions in changing rice cropping systems and their influence on C and N dynamics

Das Projekt "Plant-soil interactions in changing rice cropping systems and their influence on C and N dynamics" wird vom Umweltbundesamt gefördert und von Universität Bonn, Institut für Nutzpflanzenwissenschaften und Ressourcenschutz - Pflanzenernährung (Prof. Werner) durchgeführt. Plant-soil interactions drive the input, cycling and losses of C and N in soil. This subproject aims at elucidating the input and fate of C in the soil-plant systems and its effect of N retention in soil under different paddy management (continuous vs. alternating with maize cropping). In particular we will investigate (i) how much of the assimilate C is released by the plants into the rhizosphere soil, and how this rhizodeposition is affected by N supply, soil density and crop variety during plant development, (ii) how the exudation of C and N responds to land use change, (iii) how C released into the rhizosphere affects the turnover of soil C and utilization of fertilizer N, and (iv) to what degree leaching contributes to the loss of C and N from the rooted surface soil. To answer these questions, we will combine the use of isotopic 13C and 15N labeling in laboratory and field experiments with a sophisticated characterization of root exudates, root border cells, and compound-specific isotope tracing in the residues of bacteria and fungi in rhizosphere, bulk soil as well as within different dissolved organic and inorganic carbon species in soil leachates. In this way and in collaboration with SP 2, 5, 6, and 7 of this research unit, our project links the cycling of C and N in paddy soils to one of its most prominent drivers, the release of organic compounds by roots.

SP 3.1 Economic analysis on the effects of management and policy measures aiming at a reduction of the environmental burden from high-level agricultural production in the North China Plain

Das Projekt "SP 3.1 Economic analysis on the effects of management and policy measures aiming at a reduction of the environmental burden from high-level agricultural production in the North China Plain" wird vom Umweltbundesamt gefördert und von Universität Hohenheim, Institut für Landwirtschaftliche Betriebslehre (410), Fachgebiet Landwirtschaftliche Betriebslehre (410b) durchgeführt. In the second phase of subproject 3.1 is envisaged to model representative farms. The models will be structured in a way that not only the production but also the material balances can be represented. In particular the nitrogen balance, the carbon balance and the water balance will be incorporated. Gas and particulate matter emissions can be considered as well, as far as there are sufficient data available. The modelling aims at integrating on farm level all baseline data surveyed in other sub-projects and at quantifying and valuating at farm level the already worked out management measures for reducing environmental burden while increasing production efficiency. The focus will be on measures for reducing nitrogen fertilisation, the interrelation between management activities and carbon/nitrogen balance, effects of nitrogen deposition on the operational nutrient management, water efficiency, etc. Another part for the impact analysis shall be the extent to which cropping practices elaborated in other sub-projects can be alternatives for the prevailing wheat-maize-rotation. Thereby cotton, groundnuts, soybeans, vegetables, and row intercropping are to be analysed and valued on farm level. Furthermore, the sub-project shall provide other sub-projects with indicators which are necessary in order to optimise breeding and management programmes under consideration of economic factors. Another aim of the sub-project is to carry out economic impact analyses of possible policy measures. To do so, realistic concepts of the Chinese agricultural policy as e.g. a reduction of the subsidies on means of production, in particular on nitrogen, water, etc. and their possible impact on quantities produced, input quantities applied, nutrient and water efficiency, income and other criteria are to be investigated. Furthermore, the influence of stages of an increasing mechanisation on production, income and structural changes can be investigated. Finally, open questions and approaches for further research will be derived through a sensitivity analysis.

Formation of brine channels in sea ice

Das Projekt "Formation of brine channels in sea ice" wird vom Umweltbundesamt gefördert und von Fachhochschule Münster, Fachbereich Physikalische Technik durchgeführt. Within this interdisciplinary project the formation of brine channels in sea ice will be explored. The microscopic properties of sea ice, especially the permeability plays an important role for the energy exchange between ocean and atmosphere and is determined by the brine channel volume. The brine channel structure will be measured by computer tomography and image analysis. We intend to describe the channel structure by two phenomenological models, a morphogenesis approach of Alan Turing in connection with the phase transition theory of Ginzburg and Landau, and the phase field method with respect to the Cahn-Hilliard equation. We solve these nonlinear evolution equations in two and three dimensions and compare the size and texture of the brine channels with the measurements. In addition to the phenomenological equations we support our studies with molecular dynamics simulations and the density functional theory in order to obtain deeper insights at the molecular scale. Comparative first-principles studies will then enhance the trust in the extracted parameters and will lead to classical density functional for the two phases. We will discuss the phase transitions in terms of a phenomenological theory based on microscopic parameters and try to extract the underlying mechanism for the formation of water-ice boundaries. Specifically, we want to explore three theoretical questions: (i) How are ice-water melting fronts moving, (ii) How are brine channels formed and (iii) How do surface properties influence the structure formation of brine channels. The project is based on the experiences of three fields, the theoretical biological physics, chemical physics and the many-body theory. The final aim of the project is to provide input parameters for global climate models.

Transports and variability-driving mechanisms in Flemish Pass at the western boundary of the subpolar North Atlantic (FLEPVAR)

Das Projekt "Transports and variability-driving mechanisms in Flemish Pass at the western boundary of the subpolar North Atlantic (FLEPVAR)" wird vom Umweltbundesamt gefördert und von Universität Hamburg, Fachbereich Geowissenschaften, Institut für Meereskunde durchgeführt. Labrador Sea Water (LSW) formed in the Labrador Sea constitutes the lightest contribution to North Atlantic Deep Water (NADW), a conglomerate of water masses that form the cold return flow of the Atlantic meridional overturning circulation (MOC). Climate variability can be modulated by changes in the MOC strength; such changes are thought to be linked to variations in LSW formation. The Deep Western Boundary Current (DWBC) is the main southward pathway for newly formed LSW. Topographic obstacles at the southern exit of the Labrador Sea split the DWBC into an upper branch carrying LSW through Flemish Pass (1200m sill depth) and a branch carrying all NADW components along the continental slope around Flemish Cap. Up to now, transports through Flemish Pass and their contribution to the MOC are still uncertain, the importance of the pass for the export of LSW and its associated variability are yet unknown. In this project the transports through Flemish Pass will be quantified, and mechanisms driving and governing the variability of the flow will be investigated. The project focuses on the following questions: What is the magnitude of transports for waters passing through Flemish Pass and their associated variability? Which processes drive the variability? What is the relevance of the deep water export through Flemish Pass for the MOC, especially when compared to the DWBC export? Are both deep water export pathways (through Flemish Pass or around Flemish Cap) coupled? What processes govern the inflow of deep water into Flemish Pass? To answers these questions, ship-based measurements and time series from moored instruments in the Flemish Pass will be analyzed in conjunction with output from two state-of-the-art Ocean models run at high-resolution.

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