Experimental investigation and simulation of HLM/water interaction in LIFUS5/Mod2 facility for supporting LFR safety analysis

The present thesis work has been carried out during an internship at ENEA Brasimone Research Centre (Italy). The technical activity was conducted in the framework of LEADER project (European Lead-cooled advanced Demonstration Reactor), launched from EURATOM under the 7th Framework Programme. This work contributes to the research and development activities focused on safety of Gen. IV reactors employing as primary coolant Heavy Liquid Metal (HLM). For these reactors a pool-type configuration in which the steam generators are inside the reactor vessel is provided. Therefore, the interaction between the secondary side coolant (water) and the HLM (e.g. steam generator tube rupture) has to be considered as challenging safety issue in the design and also in the preliminary safety analysis of these reactor types. In this framework, the experimental separate effect facility LIFUS5/Mod2, installed at ENEA Research Center, was modified (i.e. top flange, test section and, partially the instrumentation and control system), installing a new test section having a geometry representatives of the tube bundle of ELSY steam generator. Tests were executed to study the interaction between LBE and water, with boundary and initial conditions relevant for the first seconds of the SGTR accident, as well as to demonstrate the reliability of computer codes in simulating the phenomena of interest. The activity can be divided into two main parts: one experimental and the second based on code application. The former has been employed for supporting the preparation of LIFUS5/Mod2 facility, the assembling of LEADER test section, the documentation of the facility configuration and instrumentation, the execution of the preparatory (i.e. protective cap pressure tests) and commissioning (i.e. tests procedures and acquisition system) tests. The experimental work was completed with the design, execution, analysis and documentation of two tests, B1.1 and B1.2. These experiments provided pressure, temperature and strain trends versus time at an acquisition frequency up to 10 kHz, suitable for the analysis of interaction phenomena and the code validation. The pressure trends have been highlighted a remarkable damping of pressure wave propagation generated. This is caused by the impact with the tube bundle (that was not damaged) and also by the forced passage through the lateral surface of the test section. This observation is also supported by the strain gage signal trends. The second part of the activity has been focussed on the use of codes for supporting the experimental campaign, the design of experiments and for the experimental data analysis. RELAP5/MOD3.3 has been used to perform the analysis of the facility water injection line and to simulate the conditions reached by water before the interaction phase for test B1.1. This was aimed at improving the understanding of the experiments as well as to improve the SIMMER-III code post-test activity. Indeed, the new configuration of LIFUS5/Mod2 facility was modelled by SIMMER-III code. The simulation of the first test (B1.1) was carried out. The post-test was mainly based on the comparisons of the experimental and calculated pressure trends. The analysis has shown results excellent simulation of the first pressure peak resulting from the rupture of the injector. Instead, the increase in pressure due to the evaporation of water injected was slightly overestimated by the code, due to geometrical approximations of SIMMER-III model

Rewetting in Mediterranean reclaimed peaty soils and its potential for phyto-treatment use

A pilot experimental field combining rewetting of reclaimed peaty soils and water phyto-treatment was set up in the Massaciuccoli Lake basin (Tuscany, Italy) to reduce the water eutrophication and peat degradation caused by almost a century of drainage-based agricultural use. In this paper, we investigated the restoration process occurring consequently to the conversion of a drained area in a natural wetland system (NWS) (the partial top soil removal, the realization of a perimeter levee to contain the waters, the rewetting with the drainage waters coming from the of surrounding cultivated areas) and the capability of the spontaneous vegetation to catch nutrients acting as a vegetation filter. To follow the restoration process over time (2012e2016), we used a mixed approach merging phytosociological surveys with ortophotos taken by an Unmanned Aerial Vehicle (UAV). During the last year of observation (2016), we performed destructive sampling on the most widespread plant communities in the area (Phragmites australis and Myriophyllum aquaticum community) to quantify the biomass production and the uptake of nitrogen and phosphorus. Stands of Phragmites australis (Cav.) Trin. ex Steud. yielded more than Myriophyllum aquaticum (Vell.) Verdc. (4.94 kg m-2 vs 1.08 kg m-2). M. aquaticum showed higher nutrient contents (2.04% of N and 0.35% of P), however P. australis was able to take up more nutrients within the NWS because of its larger cover and productivity. In the perspective of maximizing the plant development and consequently the amount of nutrients extracted from treated waters, the authors suggest 4-5 year-long-harvesting turns, better occurring in spring-summer

A multi-adaptive framework for the crop choice in paludicultural cropping systems

The conventional cultivation of drained peatland causes peat oxidation, soil subsidence, nutrient loss, increasing greenhouse gas emissions and biodiversity reduction. Paludiculture has been identified as an alternative management strategy consisting in the cultivation of biomass on wet and rewetted peatlands. This strategy can save these habitats and restore the ecosystem services provided by the peatlands both on the local and global scale. This paper illustrates the most important features to optimise the crop choice phase, which is the crucial point for the success of paludiculture systems. A multi-adaptive framework was proposed. It was based on four points that should be checked to identify suitable crops for paludicultural cropping system: biological traits, biomass production, attitude to cultivation and biomass quality. The main agronomic implications were explored with the help of some results from a plurennial open-field experimentation carried out in a paludicultural system set up in the Massaciuccoli Lake Basin (Tuscany, Italy) and a complete example of the method application was provided. The tested crops were Arundo donax L., Miscanthus × giganteus Greef et Deuter, Phragmites australis L., Populus × canadensis Moench. and Salix alba L. The results showed a different level of suitability ascribable to the different plant species proving that the proposed framework can discriminate the behaviour of tested crops. Phragmites australis L.was the most suitable crop whereas Populus × canadensis Moench and Miscanthus × giganteus Greef et Deuter (in the case of biogas conversion) occupied the last positions in the ranking

Bewegungserfahrungen und Doing Gender/Undoing Gender Einfluss bewegungsbiografischer Erfahrungen und subjektiver Sichtweisen zur Bewegung und zum Doing Gender/Undoing Gender auf das professionelle Handeln frühpädagogischer Fachkräfte in der Kindertagesstätte

In der Vergangenheit wurde immer wieder die Verbindung zwischen den Themen Kindertagesstätte und Gender diskutiert. Dies spiegelt sich beispielsweise in den Fortbildungen diverser Träger ebenso wieder wie in Projekten, die eine Erhöhung des Anteils männlicher Fachkräfte in der Kita zum Ziel haben. Fokussiert man insbesondere vor dem Hintergrund der Forderung nach mehr Männern im Berufsfeld den Blick auf weiblich konnotierte Fachkräfte, so legt die Diskussion die Annahme nahe, dass in ihrem Angebot verschiedene Tätigkeiten, die eher männlich konnotiert scheinen, wie beispielsweise bauen und Fußball spielen, unterrepräsentiert sind. Die vorliegende Arbeit greift diese aktuellen Diskussionen auf und analysiert bewegungsbiografische Lebensverläufe sowie subjektive Sichtweisen zum Doing Gender und Undoing Gender frühpädagogischer Fachkräfte in der Kindertagesstätte. Dabei stehen die Forschungsfragen, wie und wo Geschlecht in bewegungsbiografischen Interviews auf sprachlicher Ebene konstruiert wird bzw. wie und wo sich in den Antworten der Erzählpersonen Neutralität zeigt und welche Bedeutung Motive zur Bewegung bei den benannten Doing Gender- und Undoing Genderprozessen spielen, im Mittelpunk der Analyse. Basis des gesamten Forschungssettings ist die „Grounded Theory Methodologie“ (GTM), die als Methode der qualitativen empirischen Forschung den Rahmen bildet, in dem das teilnarrative Leitfadeninterview und die Gruppendiskussion miteinander verbunden werden. Im Rahmen der Dissertation wird die Historie des Berufes der frühpädagogischen Fachkraft als Frauenberuf nachgezeichnet und in seiner Relevanz für zukünftige Aus- und Fortbildungsmodule expliziert. Das Fazit beschäftigt sich mit der Forderung nach einer gendersensiblen Pädagogik, in der die Reflexion des sprachlichen Handelns und der eigenen Bewegungserfahrungen verstärkt angeregt werden sollten

Unified description of equation of state and transport properties of nuclear matter

Correlated basis function perturbation theory and the formalism of cluster expansions have been recently employed to obtain an effective interaction from a state-of-the-art nucleon nucleon potential model. The approach based on the effective interaction allows for a consistent description of the nuclear matter ground state and nucleon-nucleon scattering in the nuclear medium. This paper reports the the results of numerical calculations of different properties of nuclear and neutron matter, including the equation of state and the shear viscosity and thermal conductivity transport coefficients, carried out using the effective interaction.Comment: Invited talk at the Sixth Conference on Perspectives in Hadronic Physics (ICTP, Trieste, May 2008). To be published in the proceedings (AIP

“A case of ecological renaturation in a drained Mediterranean peatland: the case study of the Massaciuccoli Lake basin (Tuscany, It)”

The Massaciuccoli Lake floodplain is located in the Natural Park of San Rossore, Migliarino and Massaciuccoli in NW of Tuscany (Italy). Since the 1930s, a large part of the Massaciuccoli floodplain has been drained for agricultural purposes. To ensure a water table depth suitable for cultivation, a complex network of artificial drains and pumping stations has been used to drain the superficial aquifer and rainwater. Land use is characterised by conventional agriculture (covers 80% of the area) and periurban infrastructures, such as a wastewater treatment plant. In the peatland area, cropping systems are based on continuous production of maize (Zea mays L.), sunflower (Heliantus annuus L.), wheat (Triticum spp. L.). As a consequence of land use, several environmental concerns arose in the last 50 years. The most important concerns are those related to: I. eutrophication of the lake due to nutrient enrichment (N, P) in the surface- and groundwater. II. the subsidence rate (2-3 m in 70 years) due to compaction and increased mineralization of peat. The project RestoMedPeatland (https://sites.google.com/site/restomedpeatland/) started in 2011, identified rewetting and setting-up a phyto-treatment system as the solution for improving water quality,slowing down soil organic matter (SOM) mineralization, and, therefore, a method to restore the ecological functions of this site. A 15 ha experimental area was used to compare the efficiency of three different systems (A: constructed wetland, B: paludiculture system and C: natural wetland in treating the eutrophic drainage water coming from a sub-watershed in the reclamation district.In the natural wetland (C), after top soil removal, excavation and rewetting with drainage water, the vegetation has evolved naturally. The surveys carried out during the four years after pilot experimental field, highlighted the development of a spontaneous hydro-hygrophilous vegetation. This was mainly composed of helophytic communities dominated by Phragmites australis (Cav.) Trin. and Typha latifolia L., in addition to monophytic populations of Myriophillum spp., occupying different areas of the system according to the depth of excavation, for about 50% of the whole surface. The flora, currently, consists more than 30 species, as hydro-hygrophilous Alisma plantago-aquatica L., Juncus effusus L., Apium nodiflorum (L.) Lag, Lemna minor L., characteristic of the nearby Massaciuccoli Lake. The data collected so far showed a high and progressive growth of the biomass of the natural area, a dynamic upward trend of floristic-vegetation biodiversity, and, from a technical standpoint, a large phyto-treatment capability

Renaturation dynamics after the rewetting of a Mediterranean agricultural peatland

A new research project combining peatland rewetting and water phyto-treatment was set up in the Massaciuccoli Lake basin (Tuscany, Italy) to restore the peat degradation status and the water eutrophication conditions caused by almost a century of drained-based agricultural use. In a large scale phyto-treatment system, three different strategies (constructed wetland system, paludicultural system, natural wetland system) were studied to evaluate their efficiency in abating the nutrients loads from the drainage waters and to stop the peatland degradation. In this research, we investigated the renaturation process occurring within the natural wetland system as a result of the different disturbances carried out: the top soil removal in the perimeter area, the realization of a perimeter levee to contain the waters, the rewetting with the waters coming from the drainage of surrounding areas

Cross-cultural adaptation and validation of the Victorian Institute of Sports Assessment for Gluteal Tendinopathy questionnaire in Italian and investigation of the association between tendinopathy-related disability and pain

Background The Victorian Institute of Sports Assessment for gluteal tendinopathy (VISA-G) questionnaire has recently been proposed as a condition-specific patient reported outcome measurement tool to assess the tendinopathy-related disability. Aim The aim was to evaluate the reliability of the Italian version of the VISA-G questionnaire and its construct validity and to investigate the association between tendinopathy-related disability and pain. Design It consists in a cross-sectional study. Setting The location of the study was a university laboratory. Population We evaluated patients with gluteal tendinopathy (N.=38) and healthy controls (N.=38). Methods Subjects were asked to fill the VISA-G questionnaire twice to evaluate its reliability. The construct validity was evaluated by comparing the VISA score with the Oswestry Disability Index score. Moreover, pain intensity, extent and location were also investigated. Results The VISA-G scores showed non-significant changes in the median values and the values of intraclass correlation coefficient showed very high correlation between the first and second administration (ICC>0.90 in both populations). No significant correlations were found between VISA-G score and either pain extent (R=-0.05, P=0.76), or resting pain intensity (R=-0.13, P=0.45), or palpation pain intensity (R= 0.01, P=0.97). Conversely, a high (and significant) negative correlation was obtained between VISA-G score and Oswestry Disability Index score (R=-0.80, P<0.0001). Conclusions These results indicated that the VISA-G Italian version presents excellent test-retest reliability. Clinical rehabilitation impact The evaluation of gluteal tendinopathy-related disability through VISA-G can be useful for the prognostic assessment and/or follow-up of tendinopathy patients in combination with the pain drawing assessment of pain extent

How Do Metal Ion Levels Change over Time in Hip Resurfacing Patients? A Cohort Study

Metal-on-metal hip resurfacing (MOM-HR) is offered as an alternative to traditional hip arthroplasty for young, active adults with advanced osteoarthritis. Nevertheless, concerns remain regarding wear and corrosion of the bearing surfaces and the resulting increase in metal ion levels. We evaluated three cohorts of patients with Birmingham hip resurfacing (BHR) at an average follow-up of 2, 5, and 9 years. We asked whether there would be differences in ion levels between the cohorts and inside the gender. Nineteen patients were prospectively analyzed. The correlation with clinical-radiographic data was also performed. Chromium, cobalt, nickel, and molybdenum concentrations were measured by atomic absorption spectrophotometry. Chromium and cobalt levels demonstrated a tendency to decrease over time. Such tendency was present only in females. An inverse correlation between chromium, implant size, and Harris hip score was present at short term; it disappeared over time together with the decreased ion levels. The prospective analysis showed that, although metal ion levels remained fairly constant within each patient, there was a relatively large variation between subjects, so mean data in this scenario must be interpreted with caution. The chronic high exposure should be carefully considered during implant selection, particularly in young subjects, and a stricter monitoring is mandatory

Review of contemporary sound installation practices in Québec

Continuing a trend of publications investigating sound art within a specific geographical context, this paper proposes an original view of the sound installation practice in Que´bec. This study is part of a research project aiming at building new theoretical and practical tools for the documentation of such artworks. In this paper we present the outcomes of the first phase and its connection with the bigger picture of the project, which is the questioning of the relevance of spatial audio recordings with six degrees of freedom (6DoF) for mediating the capture of knowledge relating to the sensory experience of a work. During the first phase, we developed a conceptual descriptive framework based on a mixed-methods approach, top-down and bottom-up, consisting in a systematic review of literature paralleled with a categorization of contemporary sound art production in Que´bec based on publicly available documentation. This process led to a formal and quantitative depiction of the Que´bec scene, which aims to guide both the selection of case studies for the next phases but also to be part of the conceptual tools for investigating the sensory experience of these works. This quantitative depiction of the scene will thus foster a qualitative investigation of the sensory experience of sound art installations and the knowledge that may be lost in standard written documentation practice with an original methodological framework