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Access to research infrastructures has been supported by the European Commission under different financial schemes. During the 6th EURATOM Framework Programme the instrument introduced by the European Commission were the Integrated Infrastructure Initiatives (I-3). Moreover, funding schemes to support Education and Training for students and professional developments were defined also. The main difference between these two funding schemes is that I-3 are topic-driven projects with access to infrastructure components, while the Education and Training related projects have a mobility component that is applied for the different research topics. The outcome of projects as TALISMAN (I-3), EFNUDAT/NUDAME (I-3), GENTLE (mobility), ENEN-plus (mobility), NUGENIA-plus (mobility within TA of NUGENIA) and ESNII-plus (I-3 similar) will be shortly presented as well as the future European Commission plans in the field of access to research infrastructure.

In this work, laser heating is used to experimentally investigate the high-temperature behavior of the U-Fe-Zr-O system using arc-melted samples with various nominal compositions. Three-phase transitions are observed in the vicinity of ~1100, ~1700, and ~2200 K. Principal component analysis of the phase transition temperatures in the course of laser-heating thermal cycling indicates that the phase transition around ~1100 K is driven by the interaction of stainless steel (SS) with metallic U, the phase transition around ~1700 K by the melting of stainless steel, and the phase transition above ~2000 K by the eutectic melting of UO2. The results also reveal two hitherto overlooked interactions in the U-Fe-Zr-O system, which could have severe consequences for the containment of corium inside the reactor pressure vessel (RPV). First, the phase transition temperatures of the samples varied extensively as a result of the laser-driven rapid thermal cycling. Variations of up to 390 K were observed in the phase transition temperatures, suggesting that depending on the initial conditions of corium formation, the corium-driven ablation of the RPV wall could commence significantly earlier than the current state-of-the-art severe accident codes would predict. Additionally, evidence of a large exothermic reaction between zirconium and molten steel was observed upon SS melting. Such phenomenon may also be driven by material segregation during fast heating and cooling. If such a mechanism is activated during a severe nuclear accident, it can have an important impact on the overall thermal balance of the RPV. [ABSTRACT FROM AUTHOR]

In this work, the performance of on-board vehicle exhaust emission sensors is investigated and compared to reference laboratory and on-road instrumentation for two modern diesel light-duty commercial vehicles, type-approved as Euro 6d-TEMP-EVAP-ISC and Euro 6d-ISC-FCM. The first step of the analysis was to perform emissions tests in the laboratory and compare the NOx concentrations registered by the vehicle sensors available at the engine-out and tailpipe positions with those recorded by reference laboratory instrumentation. In a second step, tests were also conducted on road, comparing the performance of on-board sensors with those of Portable Emission Measurement System (PEMS) analysers, which were taken as references. The uncertainty related to exhaust flow measurements was also addressed. In particular, emissions factors calculated using the flow rates measured either in the laboratory or on-road were compared to those obtained by computing exhaust flows with on-board recorded data available from the vehicle electronic control unit. Results showed maximum deviations on the order of 34% in laboratory tests and of 21% during on-road measurements. Finally, measurements were also carried out during a diesel particulate filter regeneration event, showing the good performance of the on-board sensors even when high NOx concentrations were present. These conditions can be similar to those experienced in the case of an after-treatment system malfunction or of a high-emitting event, and can thus be of interest for real-time malfunction identification and monitoring. [ABSTRACT FROM AUTHOR]

The structure and charge distribution is investigated in the UO2-U4O9 system. UO(sub 2+x) differs from PuO(sub 2+x) in its substantially shorter An-oxo distances and no sign of stable coordination with H2O and its hydrolysis products.

Material systems such as U–Zr–O, Fe–Zr–O, and Zr–O have been recognized as fundamental for the analysis of in‐vessel nuclear fuel debris behavior during a severe meltdown accident. In the present work, the evaporation behavior of ZrO2 and Zr–Fe–O systems are investigated using heating with laser pulses of millisecond duration and time‐of‐flight mass spectrometry. The relative partial pressures of main species of vapor over ZrO2 and ZrO2–FeO systems were measured at temperatures above 2750 K. The temperature dependence of O/Zr atomic ratio in vapor over zirconia was analyzed: it turned out that evaporation occurs in a noncongruent mode at temperatures above 3000 K. Evaporation of the Zr–Fe–O system was greatly affected by the fast evaporation of FeO, implying that the atomic Zr/Fe ratio, less than 0.1 below 3000 K, significantly increased with temperature. Moreover, the ratios of main vapor components were defined only by the surface temperature, independent of the zirconia sample origin. [ABSTRACT FROM AUTHOR]

The melting temperatures of two different ZrB2 ceramics were studied using laser induced melting. ZrB2 having a low Hf content, produced by reaction hot pressing, had a melting temperature of 3546 K and a commercial grade ZrB2 had a melting temperature of 3553 K. Uncertainty of the temperature measurements was 1% of the absolute temperature, or ~35 K for both materials based upon 2‐sigma and a 95% confidence interval. While these values were consistent with the previously reported ZrB2 melting temperature of 3518 K, this study was able to measure Tm with less uncertainty than previous studies (±45 K). Furthermore, this study assessed the effect of Hf content on melting temperature, finding that melting temperature did not change significantly for hafnium contents of 1.75 to 0.01 at%. This study also measured a normal spectral emissivity of 0.34 for ZrB2 at 3000 K. The emissivity decreased to 0.28 at the melting temperature, then, stabilized at 0.30 in a liquid phase. [ABSTRACT FROM AUTHOR]

Access to research infrastructures has been supported by the European Commission under different financial schemes. During the 6th EURATOM Framework Programme the instrument introduced by the European Commission were the Integrated Infrastructure Initiatives (I-3). Moreover, funding schemes to support Education and Training for students and professional developments were defined also. The main difference between these two funding schemes is that I-3 are topic-driven projects with access to infrastructure components, while the Education and Training related projects have a mobility component that is applied for the different research topics. The outcome of projects as TALISMAN (I-3), EFNUDAT/NUDAME (I-3), GENTLE (mobility), ENEN-plus (mobility), NUGENIA-plus (mobility within TA of NUGENIA) and ESNII-plus (I-3 similar) will be shortly presented as well as the future European Commission plans in the field of access to research infrastructure. [ABSTRACT FROM AUTHOR]