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Advancements in americium-based ceramics for Radioisotope Power Systems: Material selection, fabrication and thermoelectric effect demonstration
No full textThis work provides an in-depth analysis of the extensive research and development activities on americiumbased ceramics for space applications, particularly as heat source for radioisotope power generation. Our pioneering efforts focus on synthesizing and characterizing various americium ceramics with fluorite, monazite, perovskite, zircon, and pyrochlore structures, and assessing their potential for use in Radioisotope Power Systems (RPSs). This study identifies uranium-stabilised cubic americium oxide as the best candidate among the ceramic forms analysed, due to its superior stability and performance under extreme conditions relevant to space missions. The review emphasises the unique facilities and methodologies employed, including remote-handling techniques and advanced material characterization, to overcome the challenges posed by the high radiation dose and specific activity of 241Am when working with gram quantities.JRC.G.I.5 - Nuclear Science and Innovation for Energy and Healt
TSO-DSO Flexibility Regions are Non-Convex
No full textContrary to the prevalent assumption in the literature that TSO-DSO flexibility regions are convex, this paper demonstrates that these regions are generally non-convex. Using a simple two-node counterexample, we derive analytical expressions for the flexibility region at the TSO-DSO interface, showing that minimum voltage limits inherently induce non-convexity. This finding debunks convexity-based approaches in numerous methodologies and calls for their critical reevaluation to ensure accurate aggregation of distribution-level flexibility for transmission system operations.JRC.C.3 - Energy Security, Distribution and Market
CCRI.RI(II)-K2.Pa-231 Key Comparison of activity measurements of the radionuclide 231Pa
No full textThe introduction over the last decade of radionuclide therapy based on 223Ra and 227Th has reawakened interest in the radionuclides of the 235U decay series (the 4n+3 decay chain). This has coincided with a requirement for improved accuracy in dating of long-lived radionuclides for nuclear forensic and for geological purposes. Thus, 231Pa has become the subject of revived interest in recent years.
The short-term ingrowth of the decay progeny is of interest to nuclear forensic science since it enables the direct calculation of the separation age of enriched 235U[1]; separation times based on the 234U-230Th chain may also be calculated, but are more complex due to the reliance on the 238U-234Th-234mPa-234U-230Th decay family. Furthermore, since protactinium fluorides are non-volatile at ordinary temperature, the build-up of 231Pa in fuel enrichment facilities may provide information on throughput of separation units as well as the whole plant.
In the longer term, the characterisation of sedimentation rates is facilitated by a range of natural nuclear chronometers that include 231Pa/235U to provide information concerning sediment formation, and the measurement of 231Pa:230Th mass ratios (as well as 231Pa:235U and 230Th:234U mass ratios) may also provide information of global temperature trends over the 100-200 ka range[2].
This report summarises the results of an international comparison of the activity per unit mass of the same 231Pa solution along with a new half-life determination[3].
To reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database https://www.bipm.org/kcdb/.
The final report has been peer-reviewed and approved for publication by the CCRI, according to the provisions of the CIPM Mutual Recognition Arrangement (CIPM MRA).JRC.G.II.6 - Nuclear Data and Measurement Standard
Knowledge Centre for Biodiversity Datasets
Get PDFCollection of datasets related to the work of the European Commission Knowledge Centre for BiodiversityJRC.D.6 - Nature Conservation and Observation
TRACE
Get PDFTRACE (Territorial Risk Assessment of Climate in Regions of Europe) extended the JRC PESETA IV by downscaling it to the regional level in order to inform about the geographical asymmetries of climate risks in Europe and adding a fourth global warming level scenario (4°C) to the previous scenarios assessed (1.5°C, 2°C, and 3°C). Different impact datasets will be provided under this collection (e.g. Air quality, Droughts, Temperature-related mortality, Wildfires, etc)JRC.C.6 - Economics of Climate Change, Energy and Transpor
Global synthesis of apple pollination research highlights general pollen limitation and positive contributions of wild bees compared to honeybees
No full textApple is one of the most important pollinator-dependent fruit crops worldwide. To secure high-quality yields, it is crucial to know which, and to what extent, pollinating insects contribute to its pollination success as measured by fruit set, fruit weight and seed set. We perform a meta-analysis of field studies conducted across multiple orchards on insect-mediated pollination in apple cultivation, using raw data from 29 studies, totalling 532 orchard replicates. We assessed the extent of pollen limitation on different pollination outcomes and assessed the contribution of honeybees, wild bees and bee species richness to apple pollination. Across all studies, we detected strong evidence of pollen limitation for fruit set and seed set, but not for fruit weight. Honeybees were the most abundant flower visitors (average relative visitation of 71.9\%) compared to wild bees; but when correcting for their pollination efficiency, the relative pollination contribution of honeybees was lower compared to their relative visitation (vice versa for solitary bees). We conclude that honeybee visitation rate did not influence fruit or seed set; yet increasing honeybee visitation had a small, negative effect on fruit weight. Fruit set was not influenced by wild bee visitation rate, whereas wild bee visitation had a small, but clear positive effect on fruit weight and seed set. Bee species richness had a small, positive effect on seed set; whereas it did not affect fruit set and fruit weight. Syntheses and applications. Our study highlights that pollen limitation is common in this global crop. While managed honeybees are dominant pollinators, a diverse community of wild bees contributes significantly to apple pollination and high-quality yield. The positive effect of wild bees and species richness on fruit weight and seed set demonstrates that wild bee pollination results in better-quality fruit production (increased weight \& seed set). Therefore, our synthesis highlights the importance of conserving pollinator diversity to maintain pollination services. The absence of a clear effect of honeybee visitation rate on fruit and seed set, coupled with its negative impact on fruit weight, suggests a need for further optimisation of honeybee management to improve the cost-efficiency of pollination management.JRC.D.3 - Land Resources and Supply Chain Assessment
Policy Recommendations for Large-Scale Grazing Systems in Europe: Preserving Territorial Identity and Addressing Pressures
No full textSafeguarding the remaining Large Scale Grazing Systems (LSGS) in Europe and improving targeted territorial support can have benefits for biodiversity, wildfire prevention, rural economies, cultural landscapes, and food security. Large scale grazing helps maintain habitats, reduces the risk of large-scale fires by managing fuel loads, supports rural jobs and incomes, and preserves traditional farming practices and scenic vistas. Systematic research is particularly important for LSGS in Europe. These are cultural landscapes located in marginal areas and at high risk of farm abandonment. At the same time, LSGS are a main repository of cultural and environmental values, with many of them linked and supported by activities around grazing. The objective of this research was to link grazing-supportive land use and vegetation types with grazing management in a wide range of European environments.
Our study is based on an expert-derived perception of change and the identification of the main constraints and opportunities for a wide range of European LSGS located in different bioregions. Through this approach, we rated LSGS for their social ecological values and formulated common and shared proposals to enhance resilience that can be used for policy design and implementation. A questionnaire was administered to 46 experts (with backgrounds in environmental, socio-economic and grazing management disciplines) in 22 European countries to collect data on 48 variables. The main European environmental zones are represented: Atlantic (eight study areas); Alpine (11), Boreal (six), Continental (seven); and Mediterranean (14). The results revealed a high level of correlation amongst responses, which indicates that there are areas of common ground for policy development covering diverse LSGS in Europe. The LSGS are assessed according to criteria related to their identity, environment, economics and social characteristics.
Overall, downward trends are observed for these criteria, although LSGS score high on having distinct identities. Furthermore, in terms of economic activities, 96% of the experts do not see alternatives for grazing related activities in these areas. The main weaknesses and corresponding improved management alternatives voiced by the participants included: better grazing plans (named by 82% of respondents); policy reforms (59%); a marketing framework for local products (52%); support to herding labour (39%); improvement of grazing infrastructures (34%); social empowerment of local farm communities (32%); support to grazing institutions and governance (23%); and better technical support and advisory services (18%).
The Common Agricultural Policy and the Cohesion Fund will be combined in the single National Regional Partnership Fund (NRPF), retaining a ring-fenced portion for direct farmer income support. The CAP's two-pillar structure is being replaced by a more unified framework, and Cohesion funding is also being adjusted with a focus on civil preparedness and climate resilience. The information presented here may help to improve the design of policy support for LSGS as Member States start to design their National and Regional Partnership Plans.JRC.D.5 - Food Securit
Training Compute Thresholds - Key Considerations for the EU AI Act
Get PDFThis report provides an in-depth analysis of the concept of cumulative compute as a proxy for general-purpose AI (GPAI) model capabilities, with a focus on measuring and verifying training compute, defined as the computational resources used to train a model, measured in floating-point operations (FLOP). It presents two approaches to estimating training compute, namely hardware-based and parameter-based methods, and discusses their strengths and limitations, including the challenges of estimating training compute for complex architectures and the need for standardised methodologies. The report also explores the challenges of verifying declared and undeclared training runs, and discusses potential verification methods, including concordance between measurement approaches, whistleblower protection, and monitoring of large compute clusters. Additionally, it examines the regulatory context, including the EU AI Act, and provides guidance on notification triggers, including the proposed notification point at the pre-training resource commitment stage, and the need for additional clarity for what constitutes reasonable certainty about threshold exceedance. The report also discusses the importance of updating training compute thresholds to maintain their effectiveness, and proposes a framework for dynamic threshold adjustment, including regular review periods and ongoing assessment by regulatory bodies and expert groups.JRC.T.3 - Algorithmic Transparenc
Healthy soils as a booster to EU competitiveness
No full textThe European Union's strategic agenda for 2024–2029 prioritizes a prosperous and competitive Europe, with soil health potentially playing a role in achieving this goal. However, the current state of European soils is of concern, with over 60 % of soils not in healthy condition, as reported by the European Union’s Soil Mission Board and the EU Soil Observatory. This results not only in environmental issues, but also economic ones, as the costs of soil degradation in the EU are estimated to be higher than €50 billion per year, underscoring the need for soil health to be placed more prominently on the political agenda. Soil-related business models, including biotechnology, remediation of contaminated sites, carbon removals and farming, regenerative agriculture, and agritech solutions, can contribute to EU competitiveness. These business models may help address most of the challenges posed by soil degradation, climate change, and biodiversity loss, while promoting sustainable agriculture practices and improving ecosystem functioning. The EU's soil remediation market is valued at €8.5 billion, with an annual growth rate of 5 %. The EU Carbon Removals and Carbon Farming Regulation provides a framework for certifying carbon removals, with potential revenue of €6 billion per year. Regenerative agriculture, which prioritises soil health and ecosystem services, can increase crop yields, reduce dependency on synthetic fertilisers and pesticides, and promote biodiversity. Agritech solutions, such as precision agriculture and artificial intelligence, can optimize farming practices, reduce costs, and improve environmental sustainability. Here we present the potential of soil-related business models to contribute to EU competitiveness, while addressing environmental and societal challenges. However, a number of challenges remain and need to be addressed as the need for acceleration, a clear policy framework, a closer collaboration of different actors in the food supply chain and a digital transformation are still needed.JRC.D.1 - Forests and Bio-Econom
Friction and Regenerative Braking Shares Under Various Laboratory and On-Road Driving Conditions of a Plug-In Hybrid Passenger Car
No full textAlthough particulate matter (PM) pollution from vehicles’ exhaust has decreased significantly over the years, the contribution from non-exhaust sources (brakes, tyres) has remained at the same levels. In the European Union (EU), Euro 7 regulation introduced PM limits for vehicles’ brake systems. Regenerative braking, i.e., recuperation of the deceleration kinetic and potential energy to the vehicle battery, is one of the strategies to reduce the brake emission levels and improve vehicle efficiency. According to the regulation, the shares of friction and regenerative braking can be determined with actual testing of the vehicle on a chassis dynamometer. In this study we tested the regenerative capabilities of a plug-in hybrid vehicle, both in the laboratory and on the road, under different protocols (including both smooth and aggressive braking) and covering a wide range of driving conditions (urban, rural, motorway) over 10,000 km of driving. Good agreement was obtained between laboratory and on-road tests, with the use of the friction brakes being on average 7% and 5.3%, respectively. However, at the same time it was demonstrated that the friction braking share can vary over a wide range (up to around 30%), depending on the driver’s behaviour.JRC.C.4 - Sustainable, Smart and Safe Mobilit