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Solar Energy Materials and Solar Cells, 116 + (2013) 176-181. doi:10.1016/j.solmat.2013.04.019

Drought is a natural hazard that has hit Europe hard over the last decades. The DROUGHT-R&SPI project (2011-2015) advances on drought research and associated science-policy interfacing. This FP7 project works at various scales, ranging from local to the pan-EU level. In addition to the European level, the project works in six Case Studies, in Greece (local), Spain & Italy (river basin), Portugal, Switzerland, and The Netherlands (national). In the paper, the various drought science-policy interfacing approaches are described. An overall finding is that Science-Policy interfacing at detailed scales (i.e. specific to sector, context and territory) is easier than at pan-European scale. Another important conclusion is that successful science-policy interfaces develop over time, based on their specific (socio-economic, historic and institutional) circumstances and specific drought characteristics. As well, stakeholders appreciate to be engaged in science-policy activities, they express a benefit from being involved. The functioning of the science-policy interfaces has been observed to refine and improve in the case of prolonged or successive droughts.

In wetlands, a distinct zonation of plant species composition occurs along moisture gradients, due to differential flooding tolerance of the species involved. However, "flooding" comprises two important, distinct stressors (soil oxygen demand [SOD] and partial submergence) that affect plant survival and growth. To investigate how these two flooding stressors affect plant performance, we executed a factorial experiment (water depth x SOD) for six plant species of nutrient-rich and nutrient-poor conditions, occurring along a moisture gradient in Dutch dune slacks. Physiological, growth, and biomass responses to changed oxygen availability were quantified for all species. The responses were consistent with field zonation, but the two stressors affected species differently. Increased SOD increased root oxygen deprivation, as indicated by either raised porosity or increased alcohol dehydrogenase (ADH) activity in roots of flood-intolerant species (Calamagrostis epigejos and Carex arenaria). While SOD affected root functioning, partial submergence tended more to reduce photosynthesis (as shown both by gas exchange and 13C assimilation), leaf dark respiration, 13C partitioning from shoots to roots, and growth of these species. These processes were especially affected if the root oxygen supply was depleted by a combination of flooding and increased SOD. In contrast, the most flood-tolerant species (Juncus subnodulosus and Typha latifolia) were unaffected by any treatment and maintained high internal oxygen concentrations at the shoot : root junction and low root ADH activity in all treatments. For these species, the internal oxygen transport capacity was well in excess of what was needed to maintain aerobic metabolism across all treatments, although there was some evidence for effects of SOD on their nitrogen partitioning (as indicated by 865N values) and photosynthesis. Two species intermediate in flooding tolerance (Carex nigra and Schoenus nigricans) responded more idiosyncratically, with different parameters responding to different treatments. These results show that partial submergence and soil flooding are two very different stressors to which species respond in different ways, and that their effects on physiology, survival, and growth are interactive. Understanding species zonation with water regimes can be improved by a better appreciation of how these factors affect plant metabolism independently and interactively.

This work presents a study of the degradation mechanism of NMC/Graphite high power and high energy cells cycled under different depth of discharges. Analysis will be based on the study of incremental capacity curves together with the usage of the 'alawa toolbox. The goal is to investigate the main differences in degradation mechanism between the HE and HP cells.

AbstractSustainable biorefineries have a critical role to play in our common future. The need to provide more goods using renewable resources, combined with advances in science and technology, has provided a receptive environment for biorefinery systems development. Biorefineries offer the promise of using fewer non‐renewable resources, reducing CO2 emissions, creating new employment, and spurring innovation using clean and efficient technologies. Lessons are being learned from the establishment of first‐generation biofuel operations. The factors that are key to answering the question of biorefinery sustainability include: the type of feedstock, the conversion technologies and their respective conversion and energy efficiencies, the types of products (including coproducts) that are manufactured, and what products are substituted by the bioproducts. The BIOPOL review of eight existing biorefineries indicates that new efficient biorefineries can revitalize existing industries and promote regional development, especially in the R&D area. Establishment can be facilitated if existing facilities are used, if there is at least one product which is immediately marketable, and if supportive policies are in place. Economic, environmental, and social dimensions need to be evaluated in an integrated sustainability assessment. Sustainability principles, criteria, and indicators are emerging for bioenergy, biofuels, and bioproducts. Practical assessment methodologies, including data systems, are critical for both sustainable design and to assure consumers, investors, and governments that they are doing the ‘right thing’ by purchasing a certain bioproduct. If designed using lifecycle thinking, biorefineries can be profitable, socially responsible, and produce goods with less environmental impact than conventional products … and potentially even be restorative!. Copyright © 2010 Society of Chemical Industry and John Wiley & Sons, Ltd

Sustainability is commonly assessed along environmental, societal, economic and technological dimensions. A crucial aspect of sustainability is that inter-generational equality must be ensured. This requires that sustainability is attained in the here and now as well as into the future. Therefore, what is perceived as 'sustainable' changes as a function of societal opinion and technological and scientific progress. A concept that describes the ability of systems to change is adaptive capacity. Literature suggests that the ability of systems to adapt is an integral part of sustainable development. This paper demonstrates that indicators measuring adaptive capacity are underrepresented in current urban water sustainability studies. Furthermore, it is discussed under which sustainability dimensions adaptive capacity indicators are lacking and why. Of the >90 indicators analysed, only nine are adaptive capacity indicators, of which six are socio-cultural, two technological, one economical and none environmental. This infrequent use of adaptive capacity indicators in sustainability assessments led to the conclusion that the challenge of dynamic and uncertain urban water systems is, with the exception of the socio-cultural dimension, not yet sufficiently reflected in the application of urban water sustainability indicators. This raises concerns about the progress towards urban water systems that can transform as a response variation and change. Therefore, research should focus on developing methods and indicators that can define, evaluate and quantify adaptive capacity under the economic, environmental and technical dimension of sustainability. Furthermore, it should be evaluated whether sustainability frameworks that focus on the control processes of urban water systems are more suitable for measuring adaptive capacity, than the assessments along environmental, economic, socio-cultural and technological dimensions.

Abstract Vegetation is usually sparse in the desert regions, but it plays important roles in stabilizing sand dunes and combating desertification. Establishing how desert vegetation responds to changes in both natural forcing and anthropogenic interference is essential for better understanding desertification processes and their future dynamics. In this study, a comprehensive analysis of NDVI time series data in combination with climate reanalysis data and topographic data was conducted to investigate the possible effects of different external factors on desert vegetation in the Tengger desert, one of the largest deserts in northern China. The results show that vegetation is mostly distributed near the desert margins and in the interdune areas with relatively low and flat topography. Multiple NDVI datasets indicate a consistently greening trend over the entire desert during the last forty years, and the greening rates are higher at sites with sand fixation and vegetation restoration practices. After a few decades of restoration practices, vegetation greenness in these sites is approaching their natural states, but they still show large interannual variability associated with precipitation fluctuations. Therefore, the greening trend of the entire desert could be related to recent climate change towards wetter, warmer and less windy conditions, while human efforts have accelerated the rate of vegetation recovery in the restoration sites. Our study implies that the present climate change has produced conditions favorable for continued vegetation increase in the drylands of northern China, and this trend has been facilitated by policy-driven restoration projects. The combined effects of climate change, topography and human interference on desert vegetation should be considered in future restoration practices.

In ecological risk assessment, exposure is generally modelled assuming static conditions, herewith neglecting the potential role of emission, environmental and biomass dynamics in affecting bioavailable concentrations. In order to investigate the influence of such dynamics on predicted bioavailable concentrations, the spatially-resolved dynamic model "ChimERA fate" was developed, incorporating macrophyte and particulate/dissolved organic carbon (POC/DOC) dynamics into a water-sediment system. An evaluation against three case studies revealed a satisfying model performance. Illustrative simulations then highlighted the potential spatio-temporal variability of bioavailable concentrations after a pulsed emission of four chemicals in a system composed of a pond connected to its inflow and outflow streams. Changes in macrophyte biomass and POC/DOC levels caused exposure variations which were up to a factor of 4.5 in time and even more significant (several orders of magnitude) in space, especially for highly hydrophobic chemicals. ChimERA fate thus revealed to be a useful tool to investigate such variations and to identify those environmental and ecological conditions in which risk is expected to be highest.

Screens used in practice are made from various material compositions (woven fabrics, knitted fabrics, foils, open or closed structures, transparent, diffuse, aluminized, various colours) and for various purposes (energy saving, reduction in light sum, or diffuse light obscuration). An important goal of the use of screens in Dutch greenhouses is to save energy. Unfortunately, to date, there is no objective method to determine the energy-saving performance of a material under standardized conditions. Energy-saving rates are estimated by manufacturers using different methods. Growers have no way of comparing material performances independently in order to make a proper investment decision. In the current research, the goal was to develop a method to quantify the energy-saving performance of greenhouse screen materials under standardized conditions. The method is based on the scientific literature and expertise of different screen producers and growers. The research focused on the three main aspects that affect energy saving of a screen: 1) thermal radiation losses, determined by the emissivity and reflectivity for thermal infrared radiation; 2) air permeability, which determines heat convection losses, characterized at a wide range of air velocities to account for velocities by buoyancy through materials as well as for velocities by forced convection caused by internal fans; and 3) water vapour permeability, which determines latent heat losses, determined under temperature, humidity and air velocity conditions normally encountered in commercial greenhouses. For all aspects, different measurement methods were compared to choose the best method based on reproducibility, accuracy and practicability. Screen material properties were then fed into both steady-state and validated dynamic greenhouse climate models to calculate overall screen energy saving under well-defined conditions. In the current research, different screen materials from different producers were investigated. The paper describes the methodology developed and shows data on different screen materials.

In the field of the R&D of a new generation hard X-ray cameras for space applications we focus on the use of pixelated CdTe or CdZnTe semiconductor detectors. They are covered with 64 (0.9×0.9 mm2) or 256 (0.5×0.5 mm2) pixels, surrounded by a guard ring and operate in the energy ranging from several keV to 1 MeV, at temperatures between −20 and +20 °C. A critical parameter in the characterisation of these detectors is the leakage current per pixel under polarisation (∼50–500 V/mm). In operation mode each pixel will be read-out by an integrated spectroscopy channel of the multi-channel IDeF-X ASIC currently developed in our lab. The design and functionality of the ASIC depends directly on the direction and value of the current. A dedicated and highly insulating electronics circuit is designed to automatically measure the current in each individual pixel, which is in the order of tens of pico-amperes. Leakage current maps of different CdZnTe detectors of 2 and 6 mm thick and at various temperatures are presented and discussed. Defect density diagnostics have been performed by calculation of the activation energy of the material.