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AsFeP0 - A model concept for in situ investigation or arsenic and phosphate adsorption to predefined iron minerals and to characterize transformation processes of iron minerals

Shallow groundwater of the huge deltaic systems of Asia like the Red River Delta in Vietnam is often enriched in inorganic arsenic (As), threatening the health of millions of residents. The massive abstraction of groundwater in these areas locally causes an irreversible mixing of arsenic-free groundwater resources with arsenic-rich groundwater. Increased concentrations of competitive anions, especially phosphate (PO43-), decrease the immobilization capacity of the sediments. During transport, the mobility of dissolved As in local aquifers is strongly influenced by adsorption to sedimentary and ubiquitously occurring iron(oxyhydr)oxides. Additionally, arsenic-rich groundwater is often enriched in reduced iron (Fe2+) as well, which is capable to react with iron(oxyhydr)oxides, thereby inducing mineral transformations. Such transformations permanently affect the arsenic adsorption and immobilization capacity of the sediments.Within the scope of this research project, the underlying mechanisms related to As transport and the resulting threat to arsenic-free groundwater resources will be characterized in cooperation with the Swiss Federal Institute of Aquatic Science and Technology (Eawag). The research concept aims at assessing the complex interactions within the arsenic-iron-phosphate-system under field conditions at a study site next to the Red River. First, filtration experiments using local groundwater enriched in As and PO43- will be used to determine the As adsorption capacity of different and previously geochemically characterized iron(oxyhydr)oxides. In a second step, sample carrier containing As loaded iron(oxyhydr)oxides will be introduced into surface near aquifer parts of the study site (via existing groundwater monitoring wells). These samples will be exposed to local groundwater characterized by increased As, Fe2+ and PO43- concentrations for the following nine months. Using the in situ exposition of predefined iron(oxyhydr)oxides, it will be possible to distinguish potential mineral transformations and their influences on the As immobilization capacity of the respective iron(oxyhydr)oxides. By combining the results and outcomes of the field experiments, new and important conclusions regarding the mobility of As can be drawn. The data can be used to create a hydrochemical transport model describing reactive As transport within the investigation area. In addition, the results of the in situ exposition experiments will allow to draw conclusions in respective to the long term As immobilization capacity of different iron(oxyhydr)oxides, which is an essential information regarding in situ decontamination techniques.

Identification of groundwater nitrogen point source contribution through combined distribute temperature sensing and in-situ UV photometry

Agriculture is the major contributor of nitrogen to ecosystems, both by organic and inorganic fertilizers. Percolation of nitrate to groundwater and further transport to surface waters is assumed to be one of the major pathways in the fate of this nitrogen. The quantification of groundwater and associated nitrate flux to streams is still challenging. In particular because we lack understanding of the spatial distribution and temporal variability of groundwater and associated NO3- fluxes. In this preliminary study we will focus on the identification and quantification of groundwater and associated nitrate fluxes by combining high resolution distributed fiber-optic temperature sensing (DTS) with in situ UV photometry (ProPS). DTS is a new technique that is capable to measure temperature over distances of km with a spatial resolution of ca1 m and an accuracy of 0.01 K. It has been applied successfully to identify and quantify sources of groundwater discharge to streams. ProPS is a submersible UV process photometer, which uses high precision spectral analyses to provide single substance concentrations, in our case NO3-, at minute intervals and a detection limit of less than 0.05 mg l-1 (ca.0.01 mg NO3--Nl-1). We will conduct field experiments using artificial point sources of lateral inflow to test DTS and ProPS based quantification approaches and estimate their uncertainty. The selected study area is the Schwingbach catchment in Hessen, Germany, which has a good monitoring infrastructure. Preliminary research on hydrological fluxes and field observations indicate that the catchment favors the intended study.

Diffusion and advection with sorption of anions, cations and non-polar molecules in organo-clays at varying thermo-chemical conditions - validation by analytical methods and molecular simulation

The sorption of anions in geotechnical multibarrier systems of planned high level waste repositories (HLWR) and of non-ionic and organic pollutants in conventional waste disposals are in the center of recent research. In aquatic systems, persistent radionuclides such as 79Se, 99Tc, 129I exist in a form of anions. There is strongly increasing need to find materials with high sorption capacities for such pollutants. Specific requirements on barrier materials are long-term stability of adsorbent under various conditions such as T > 100 C, varying hydrostatic pressure, and the presence of competing ions. Organo-clays are capable to sorb high amounts of cations, anions and non-polar molecules simultaneously having selectivity for certain ions. This project is proposed to improve the understanding of sorption and desorption processes in organo-clays. Additionally, the modification of material properties under varying chemical and thermal conditions will be determined by performing diffusion and advection experiments. Changes by sorption and diffusion will be analyzed by determining surface charge and contact angles. Molecular simulations on models of organo-clays will be conducted in an accord with experiments with aim to understand and analyze experimental results. The computational part of the project will profit from the collaboration of German partner with the group in Vienna, which has a long standing experience in a modeling of clay minerals.

Development of Nanotechnology-based High-performance Opaque & Transparent Insulation Systems for Energy-efficient Buildings (NANOINSULATE)

NANOINSULATE will develop durable, robust, cost-effective opaque and transparent vacuum insulation panels (VIPs) incorporating new nanotechnology-based core materials (nanofoams, aerogels, aerogel composites) and high-barrier films that are up to four times more energy efficient than current solutions. These new systems will provide product lifetimes in excess of 50 years suitable for a variety of new-build and retrofit building applications. Initial building simulations based on the anticipated final properties of the VIPs indicate reductions in heating demand of up to 74Prozent and CO2 emissions of up to 46Prozent for Madrid, Spain and up to 61Prozent and 55Prozent respectively for Stuttgart, Germany for a building renovation which reduces the U-value of the walls and roof from 2.0 W m-2 K-1 to 0.2 W m-2 K-1. This reduction could be achieved with NANOINSULATE products that are only 25 mm thick, giving a cost-effective renovation without the need of changing all the reveals and ledges. Similarly, significant reductions in U-values of transparent VIPs (3 W m-2 K-1 to 0.5 W m-2 K-1) are shown by substituting double glazed units in existing building stock. Six industrial & four research based partners from seven EU countries will come together to engineer novel solutions capable of being mass produced. Target final manufacturing costs for insulation board (production rates above 5 million m2/year) are less than 7 m-2 for a U-value of 0.2 W m-2 K-1. NANOINSULATE will demonstrate its developments at construction sites across Europe. A Lifecycle Assessment, together with a safety and service-life costing analysis, will be undertaken to prove economic viability. NANOINSULATE demonstrates strong relevance to the objectives and expected impacts of both the specific call text of the Public-Private Partnership Energy-efficient Buildings topic New nanotechnology-based high performance insulation systems for energy efficiency within the 2010 NMP Work Programme and the wider NMP & Energy Thematic Priorities. Prime Contractor: Kingsplan Research and Developments Ltd.; Kingscourt; Irland.

Universal microarrays for the evaluation of fresh-water quality based on detection of pathogens and their toxins

Monitoring the quality of drinking water is of paramount importance for public health. 'Water is not a commercial product but a heritage that must be protected, defended and treated as such' (Water Framework Directive 2000/60/EC). The threat of waterborne diseases in Europe will predictably increase in the future as the human population increases and as a result of globalization and migration from non-EU countries and of climate change. Development of efficient, sensitive, robust, rapid and inexpensive tests to monitor various aspects of water quality represents an essential milestone within the strategy for control and prevention of diseases caused by waterborne pathogens and by algal toxins. Traditional methods for the detection of waterborne pathogens, based on cultivation, biochemical characterisation and microscopic detection are laborious and time-consuming; molecular biological tools have now greatly enhanced our ability to investigate biodiversity by identifying species and to estimate gene flow and distribution of species in time and space. My AQUA aims to design and develop a universal microarray chip for the high-throughput detection in water of known and emerging pathogens (bacteria, viruses, protozoa and cyanobacteria) and to assess the water quality monitoring the presence of select bioindicators (i.e. diatoms). A chip able to detect cyanobacterial toxins will also be developed. These innovative molecular tools should be amenable to automation so that they could be deployed on moorings for routine semi-continuous monitoring of water quality. My AQUA also aims to identify cyanophages potentially capable of controlling and mitigating the periodical blooming of toxic cyanobacteria in drinking water reservoirs. Overall, these innovative and cost efficient technologies will reduce energy requirements and improve performance of water treatment, and allow rapid management response to new situations brought about by environmental (including climatic) changes.

Storage of hydrogen in hydrides

Hydrogen is the ideal synthetic fuel to convert chemical energy into electrical energy or into motive power because it is light weight, highly abundant and its oxidation product is vapor of water. Thus its usage helps to reduce the greenhouse gases and it conserves fossile resources. There is even a clean way to produce hydrogen by electrolysis of water by means of photo voltaics (SvW06, VSM05, PMM05). There are various possibilities to store the hydrogen for later use: Liquid and gaseous hydrogen can be stored in a pressure vessel, hydrogen can be adsorped on large surface areas of solids, and finally crystal lattices of metals or other compounds can be used as the storage system, where hydrogen is dissolved either on interstitial or on regular lattice sites by substitution (SvW06, San99). The latter process and its reversal is called hydriding respectively dehydriding. The subject of this proposal is the modeling and simulation of that process. The main problem of a rechargeable lithium-ion battery is likewise a storage problem, because in a rechargeable battery, both the anode and cathode do not directly take part in the electrochemical process that converts chemical energy into electrical energy, rather they act as host systems for the electron spending element, which is here lithium (Li). During the last month the applicant developed and exploited a mathematical model that is capable to capture the storage problem of an iron phosphate (FePO4) cathode, where the Li atoms are stored on interstitial lattice sites (DGJ07).

Function of BAK1 in plant immunity

In nature most plants are resistant to most pathogens and disease is rather the exception than the rule. A key aspect of this phenomenon is a resistance response called 'innate immunity'. It is based on the host recognition of characteristic microbial molecules, known as MAMPs (Microbe Associated Molecular Patterns), by specific receptors called pattern recognition receptors (PRRs). A paradigm of a MAMP is flagellin, the main building unit of the mobility organ of bacteria. Bacterial flagellin is perceived by the pattern recognition receptor FLS2 (FLagellin Sensing 2) at the surface of plant cells. Binding of flagellin to FLS2 on the outside of the cells induces a set of physiological responses inside the cells, which we can easily measure in our lab and which ultimately contribute to limitation of bacterial invasion and plant resistance. Our lab has focused in the last years in understanding how FLS2, a single pass transmembrane molecule, functions to transmit the signal from outside of the cell to its inside. We could demonstrate that upon stimulation with flagellin, FLS2 associates very quickly at the plasma membrane with a second receptor known as BAK1 (BRI1-Associated Kinase 1). This was initially a big surprise because BAK1 was already known as the co-receptor of the BRI1, a plant hormone receptor which regulates plant development but not plant immunity. More recently we developed an original biochemical approach to label and detect phosphorylated receptors in cell cultures in vivo. This allowed us to show that the transmission of the flagellin signal occurs via phosphorylation of FLS2 and BAK1 within seconds after flagellin perception. In addition we could show that BAK1 is capable of regulating several PRRs other than FLS2 by forming stable complexes. Thus BAK1 appears to be a crucial regulator or plant immunity in addition to its role in plant development. Our recent progress on the plants' flagellin-sensing system was mostly obtained using Arabidopsis as plant model. In view of the ability of BAK1 to form stable complexes with PRRs in a ligand-dependent manner, we are now interested to fish out and identify new PRRs, notably from crop species, using a proteomic approach. The identification of more PRRs in different plants is a very important step toward understanding plant innate immunity. In more general terms, better knowledge about innate immunity is crucial because it may reveal new strategies to fight the devastating impact of some plant diseases.

Monitoring changes in biodiversity at regional and continental scales over the past three decades using a dynamic habitat index derived from historical satellite data

Understanding the drivers behind the loss of biodiversity currently observed is of major importance in the context of the global change discussion. For studies of biodiversity at broad spatial scales, satellite remote sensing is the premier source of information, as it is uniquely capable of covering large areas of the Earth at high temporal resolution. The underlying assumption is that satellite-derived geophysical surface parameters, such as vegetation greenness, are related to biodiversity. For that purpose, concepts such as the Dynamic Habitat Index (DHI) were recently developed. The DHI combines information on the overall greenness, the base level of vegetation cover, and vegetation seasonality at a certain location. By comparing the annual DHI with a long term mean, areas undergoing disturbances or recovery events can be delineated, which are indicative of changes in species composition and diversity. The concept of the DHI was developed for data obtained from the Moderate Resolution Imaging Spectroradiometer (MODIS) post-2000. However, for climate change impact studies a longer time series is desirable. The only sensor system suitable for such applications is the Advanced Very High Resolution Radiometer (AVHRR), which has been in orbit on various platforms since the early 1980ies. The purpose of this project was to develop a methodology to derive long term information on habitat conditions at continental scales based on historical satellite data. In particular, the goal was to adopt the principle of the DHI as developed for the MODIS sensor to an AVHRR archive at 1 km spatial resolution over Canada and to analyze long term variations in the DHI. In a first project phase, an AVHRR data set of vegetation greenness, generated in the framework of the project, was validated against the reference MODIS product. The results demonstrated a very good agreement between both data sets for a wide range of vegetation types and on various spatial and temporal scales. A historical baseline of habitat conditions post-1987 based on the DHI was subsequently generated based on the long term AVHRR data. The analysis of the DHI showed that certain areas, particularly northern parts of the Province of Quebec as well as southwestern Canada, experienced significant changes over the past two decades, which may have had significant impacts on species diversity and abundance in these areas. In the future, the methods developed in the framework of this project may be used to obtain information on long term variations in habitat conditions in areas covered by other historical satellite archives, e.g., for Europe based on an AVHRR archive hosted at the University of Bern.

Hochleistungstragwerke - HHT - Entwicklung von hochbelastbaren Verbundbauweisen im Holzbau mit faserverstärkten Kunststoffen, technischen Textilien und Formpressholz

Das Gesamtziel des Verbundprojektes besteht darin, dem nachwachsenden Rohstoff Holz durch einen neuartigen Engineering- Baustoff ein weiteres neues Marktsegment und damit einen erhöhten Absatz zu verschaffen. Im Fordergrund steht die Steigerung der Leistungsfähigkeit von Holzkonstruktionen mit Hilfe von Hochleistungsfasern, beanspruchungsgerechten Textilien sowie verdichteten und geformten Hölzern. Hieraus folgen erhebliche Verbesserungen hölzerner Tragkonstruktionen bezüglich Steifigkeit, Festigkeit, Zähigkeit, Dauerhaftigkeit und Materialeffizienz. rnMittelfristige Ziele sind: (1) Die Einführung von Hochleistungshölzern in die praktische Anwendung für hochbelastete Tragwerkskonstruktionen und (2) Die Etablierung von maßgeschneiderten Holzkonstruktionen im Bereich von Sanierungs- und Neubauvorhaben unter Ausnutzung neuer baustofflicher Eigenschaften, beanspruchungsgerechter Verstärkungen und einer neuen Technologie zur Querschnittsbildung. Besonderen Wert bei der Umsetzung der Projektziele legen die Verbundpartner auf eine stark praxisorientierte Ausrichtung der Arbeiten und die Demonstration der Projektergebnisse im Rahmen geeigneter Pilotvorhaben.rnrnIn Druckversuche an axial beanspruchten Rohrstützen wurde das Last-Verformungs-Verhalten der Leichtbauprofile untersucht. Aufgrund des großen Trägheitsmomentes der Rohrquerschnitte wurden bereits für unverstärkte Profile hohe Trag- bzw. Knicklasten ermittelt. Die Versuche an faserverstärkten Profilen haben jedoch gezeigt, dass deutliche Steigerungen hinsichtlich Traglast und Duktilität der Stützen möglich sind. Zur Vorbemessung und Analyse der Versagensmechanismen wurden Standard-Bemessungsgleichungen bzw. einfache analytische Modelle eingesetzt. Diese wurden anhand der experimentell ermittelten Daten verifiziert.rn

Modelling Heterogeneous and Homogeneous Ice Nucleation and Growth at Cirrus Cloud Levels

Many aspects of the global radiation budget are now well understood. The largest remaining uncertainty is how atmospheric aerosols modify the characteristics of clouds and how that affects the global radiation budget. This project will advance the current understanding of this indirect effect for the particularly climate-relevant cirrus clouds. Cirrus clouds are high altitude clouds, formed when atmospheric water freezes into ice crystals. They reflect infrared radiation as well as sunlight and can therefore warm or cool the surface of the Earth. Atmospheric aerosols are fine solid particles or liquid droplets in the atmosphere, examples being smoke, oceanic haze or simply liquid water. Some components of aerosols affect the temperature at which water droplets freeze and are thus capable of changing the radiative properties of cirrus clouds by influencing the number and size of the clouds' ice particles. Aerosol components which reduce the freezing temperature of water impede homogeneous nucleation, that is, the process of freezing of a droplet which is not in contact with a solid particle. Other types of aerosol, such as mineral dust, raise the freezing temperature of water by providing solid surface on which ice formation can begin (heterogeneous nucleation). Cirrus clouds are an important factor for the Earth's climate. Therefore, it is crucial that their representation in climate models can account for effects induced by anthropogenic changes in the number, size and composition of aerosols in the atmosphere. The aim of this project is to develop a representation of the formation and growth of ice particles for use in climate models. Firstly, we will develop mathematical descriptions of ice nucleation and growth rates, which account for the most important aerosol types, such as mineral dust or ammonium sulfate. An existing model will allow us to determine the effect of each of the examined substances on the properties of a cirrus cloud. The chemical and aerosol input for these experiments will be taken from a state of the art aerosol - chemistry transport model, the OsloCTM2. After developing a simplified cirrus cloud model, which will be incorporated into a global model in the last stage of the project, we can determine how and to what extent the aerosol composition influences the distribution and the radiative properties of cirrus clouds on a global scale. This project will develop the first physico-chemically based representation of cirrus cloud formation for chemistry climate models (CCMs), allowing the calculation of climate effects of changes in cirrus coverage due to anthropogenic modification of atmospheric aerosols.

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