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This article presents the results of a research project carried out in Benidorm (Alicante, Spain) during the period 2015- 2016. It explores the social representations of young people between 16 and 18 years of age, in the face of the current political and economic situation: the causes, the solutions, and those responsible for the economic crisis. The adolescents that took part in this study are in secondary school, attend the same educational institution and come from similar socio-economic contexts. They were divided into two groups. One of the groups receives Contemporary History classes (Group A) and the other does not (Group B). The data was collected from a questionnaire with questions about the crisis, regarding images from the current socio-economic crisis and commentaries from historical sources about the crises of 1873, 1929 and 2008. The results show that the group that receives History classes is more critical when analyzing the current societal problems, as well as establishing analogies with the past to explain the situations of the present, whereas the other group reproduces the opinions of the media. [ABSTRACT FROM AUTHOR]

The insulating materials for radio frequency (RF) windows and different antenna supports for heating systems and some diagnostics are still an unresolved issue in future fusion machines such as DEMO. Alumina ceramic (Al2O3) is one of the main candidate materials for these systems. The dielectric properties, such as electrical permittivity (ε) and loss tangent (tanδ), determine its power losses. Therefore, tanδ values need to be low, between 10-6 and 10-3 depending on the application. However, due to the crucial role of the manufacturing process in determining its final dielectric properties, there is the need to undertake a joint effort with the industry in order to validate a standard manufacturing route that ensures a supply of ceramic material with homogeneous and standardized dielectric properties for future fusion machines. In DEMO, these ceramic materials will be operated under extreme conditions. They will be exposed to considerable levels of neutron irradiation. Radiation Induced Conductivity (RIC) and Radiation Induced Electrical Degradation (RIED) are phenomena that influence notoriously on the dielectric performance of these materials. Therefore, their optimum properties must be tested under relevant irradiation conditions. Hence, it is important to accurately characterize their dielectric properties before irradiation to be able to compare them with the future post neutron irradiation results. Furthermore, other types of radiation such as beta and gamma are also used in the irradiation scheme to provide more information on the variation of dielectric properties of ceramics due to radiation effects. In this work, loss tangent and permittivity values of some pre-irradiated candidate materials will be presented as well as the measuring techniques used at CIEMAT. These techniques have the advantage of covering a very broad range of frequencies required for alumina applications in fusion (from kHz to GHz) and giving the best accuracy for very low losses. [ABSTRACT FROM AUTHOR]

In the following article are reported the results of a research on social representations about the economic crisis of adolescents in between 16-18 years old. The two studied groups attend the same school and come from similar socioeconomic contexts; however one of the two groups courses the subjects of Contemporary History and Economics (Group A), and the other group doesn't (Group B). The information is collected through a written questionnaire about current news and a discussion group that deals with the subject. The results show the influence of the media on the responses of both groups and a greater feasibility of the solutions proposed by the students of Economics and History. [ABSTRACT FROM AUTHOR]

In the following article are the results of a doctoral research about social representations of adolescents between 16-18 years old, as they approach their time to vote about politics and its protagonists. Different data collection instruments, questionnaires, interviews and focus groups are used. Young people show a mixed picture of politics: the moral refusal of political, but they're receptive to the urgency of political regeneration. In this context of crisis, it's arises if they believe in the new discourse of change against the bipartisanship or in economic recovery and continuity models. [ABSTRACT FROM AUTHOR]

Abstract: Molecular Dynamics simulations in bulk diamond using AIREBO potential have been used to calculate minimum displacement energy. A statistical approach has been applied calculating displacement probability curves along the main crystallographic directions. With these curves a minimum displacement energy of around 30eV can be obtained, and a weighted average energy of around 70eV. This value has been estimated as more accurate for its use in BCA displacement equations to obtain Frenkel pairs at moderate temperatures. This work also includes a study of defect states whose analysis reveals interesting results concerning the evolution of primary damage at higher PKA energies. [Copyright &y& Elsevier]

Abstract: Two cerium-monazites containing excess phosphorous were synthesized by a precipitation method. The Ce-phosphate selected samples were doped with 1.3 wt.% and 4.7 wt.% lithium and sintered in dry air. The phase evolution as a function of temperatures was investigated. The XRD and microstructural studies reveal that Ce-monazite appears at low temperature (350 °C). Lithium is incorporated into the monazite lattice up to 1000 °C. The material achieved at this temperature is a composite constituted by mainly CePO4 monazite grains, surrounding by a minor Li-Phosphate glassy phases. Precipitation of cubic Ceria, and Li3PO4 as secondary phases are also provided. Li introduction into the Ce-monazite lattice is accounted due to the fact that the main XRD monazite peaks, is significantly shifting towards higher diffraction angles. For the larger Li content sample, when temperature increases (1250 °C), the cerium oxide are the major phase depicted. The total electrical conductivity plots obtained from impedance spectra, between 25 °C and 900 °C, in dry air, indicated that the Ce-monazite decomposition starts at 1000 °C and it was evident at 1250 °C. The total conductivity decreased as precipitated Ceria phases increased. Furthermore, the total conductivity data in dry air, evidenced that both lithium ionic and electronic-hole transport govern the conduction process, similarly to what occurs in doped Sr-lanthanide based monazites. Li-doped ceria-monazite may promote electronic-hole formation by a trapping–detrapping process at Ce3+ and Ce4+ sites. Li ionic conduction contribution comes from the presence of Li3PO4, but it is restricted due to the fact that Pt block lithium electrodes were used for impedance electrical tests. The optical measurements for the lithium doped monazites show the Ce3+ luminescence band when Li is introduced that band intensity decreases providing Ce4+, which confirms hole-electronic formation. The Li role is to catalyzes the ceria-monazite crystallization and also induces the monazite Ce3+ oxidation. Finally CeO2 is the major phase found at 1250 °C. [Copyright &y& Elsevier]

Extended free‐volume positron trapping defects (positron trapping channel) and nanopores (positronium decaying channel) in the initial and modified MgAl2O4 ceramics sintered at 1200, 1300, and 1400 °C are investigated using positron annihilation lifetime spectroscopy within four‐component fitting procedure. It is established that the number and size of extended defects near grain boundaries (described by the second component) decrease with increasing sintering temperature of ceramics, which correlates with the content of additional phases in the materials. The agglomeration of nanopores occurs in the initial ceramics (described by the third component) and the decrease of number and size of nanopores in the modified ceramics. The corresponding processes of the evolution of nanopores described by the fourth component are reflected mainly in their reduction, except for ceramics sintered at 1400 °C. Such changes are associated with the evolution of porous structure and increased contact area between the grains of ceramics. [ABSTRACT FROM AUTHOR]

The literature data on the annealing kinetics of the basic radiation defects in different types of silica after gamma- and neutron irradiation were analyzed in terms of diffusion-controlled reactions. The defect migration energies and relevant pre-factors are determined. It is shown that the annealing kinetics in several gamma and neutron irradiated samples could be explained as the recombination of the E′ centers (an oxygen vacancy) with two mobile hole defects, similarly to our recent observation in neutron irradiated sapphire. The mechanism of the relevant processes and a role of OH content are discussed. [ABSTRACT FROM AUTHOR]

Abstract: EUROFER97 specimens were exposed in vacuum to lithium silicate pebbles at 550°C for up to 2880h, to evaluate its corrosion susceptibility in a simulated breeder blanket environment. The specimens and pebble bed were then analyzed and characterized by SEM-EDX, XRD, and HR-TEM. The results revealed the formation of a double chromium/iron oxide corrosion layer. HR-TEM also showed that the inner layer was amorphous, while the outer was crystalline. The amorphous layer was brittle, broke easily, and became detached from the steel. [Copyright &y& Elsevier]

The annealing kinetics of the primary electronic F-type color centers (oxygen vacancies with trapped one or two electrons) is analyzed for three ionic materials (Al2O3, MgO, and MgF2) exposed to intensive irradiation by electrons, neutrons, and heavy swift ions. Phenomenological theory of diffusion-controlled recombination of the F-type centers with much more mobile interstitial ions (complementary hole centers) allows us to extract from experimental data the migration energy of interstitials and pre-exponential factor of diffusion. The obtained migration energies are compared with available first-principles calculations. It is demonstrated that with the increase of radiation fluence both the migration energy and pre-exponent are decreasing in all three materials, irrespective of the type of irradiation. Their correlation satisfies the Meyer-Neldel rule observed earlier in glasses, liquids, and disordered materials. The origin of this effect is discussed. This study demonstrates that in the quantitative analysis of the radiation damage of real materials the dependence of the defect migration parameters on the radiation fluence plays an important role and cannot be neglected. [ABSTRACT FROM AUTHOR]

A new Deuterium-Tritium campaign (DTE2) is planned at JET in the next years, with a proposed 14 MeV neutron budget of 1.7 × 10 21 , which is nearly an order of magnitude higher than any previous DT campaigns. The neutron and gamma ray fields inside the JET device during DT plasma operations at specific locations have previously been evaluated. It is estimated that a total neutron fluence on the first wall of JET of up to 10 20 n/m 2 could be achieved, which is comparable to the fluence occurring in ITER at the end of life in the rear part of the port plug, where several diagnostic components will be located. The purpose of the present work is to evaluate the radiation damage and nuclear heating in selected functional materials to be irradiated at JET during DT plasma operation. These quantities are calculated with the use of the MCNP6 code and the FISPACT II code. In particular the neutron and gamma ray fields at specific locations inside the JET device, dedicated to material damage studies, were characterized. The emphasis is on a potential long term irradiation station located close to the first wall at outboard midplane, offering the opportunity to irradiate samples of functional materials used in ITER diagnostics, to assess the degradation of the physical properties. The radiation damage and the nuclear heating were calculated for selected materials irradiated in these positions and for the neutron flux and fluence expected in DTE2. The studied candidate functional materials include, among others, Sapphire, YAG, ZnS, Spinel, Diamond. In addition the activation of the internal irradiation holder itself was calculated with FISPACT. Damage levels in the range of 10 −5 dpa were found. [ABSTRACT FROM AUTHOR]

The structural changes produced by ion irradiation, He + (2.5 MeV), O 4+ (13.5 MeV), Si 4+ (24.4 MeV), and Cu 7+ (32.6 MeV), in different types of silica (KU1, KS-4V and Infrasil 301) were observed by IR reflection spectroscopy. The IR reflectance spectra were measured between 400 and 1400 cm −1 . Structural bands wavenumber of the three silica grades, irradiated with the same ion and fluence, is independent on OH or impurity content of silica. Modification in the surface structure of the irradiated face of a silica sample was studied monitoring the changes in the wavenumber of fundamental structural bands as function of the ion fluence. Samples irradiated at high ion fluence present a shift of known structural bands and new IR reflection bands around 608 cm −1 and between 920 and 990 cm −1 , corresponding to a new structure. The spectra of neutron irradiated samples at fluences 10 17 and 10 18 n/cm 2 were also measured and compared with ion irradiated samples. [ABSTRACT FROM AUTHOR]

Abstract: The formation and evolution of defects in materials irradiated with a homogeneous neutron source and with the Beam Raster Scanner (BRS) solution was investigated. The intensity neutron source fluctuations inherent to the BRS system were determined using the neutron transport McDeLicious code. Defects generated during irradiation were calculated using the binary collision approximation MARLOWE code, using the primary knock-on atom (PKA) energy spectrum resulting from neutron interactions with the material. In order to predict the evolution of defects during irradiation, a Rate Theory model based on ab initio parameters was developed. Our model accounts for the migration of mobile defects, the formation of clusters and their recombination. As an example, we investigated defect evolution in Fe irradiated at room temperature in both beam configurations. Simulation results clearly indicate that the defect evolution expected in the BRS configuration is nearly the same as the one expected in a homogeneous irradiation system. [Copyright &y& Elsevier]

Abstract: A rate theory model based on ab initio data was used to predict defect evolution in electron-irradiated dilute FeCr alloys during isochronal annealing. A good correlation was found between the prediction of the model and existing isochronal resistivity recovery measurements. In agreement with experimental results, our model predicts a shift of stage IE towards lower temperature with increasing Cr concentration. According to our model, stage II is found to be not only due to the recombination of I2 clusters with vacancies but also due to the annihilation of ICr and I2Cr complexes at vacancies. [Copyright &y& Elsevier]

Abstract: The exploitation of ITER tokamak will require diagnostics for machine protection, inputs to plasma control systems, evaluation and analysis of plasma parameters and performances. The equatorial visible/infrared wide angle viewing system and the radial neutron camera are the two main diagnostics of Procurement Package 11 (PP11), one of the diagnostic procurements under the responsibility of Europe, which also contains Equatorial Port Plug 1 and seven other diagnostics supplied by Europe or other ITER partners and integrated in the same Port Plug. Significant progress has recently been made in the development of the equatorial visible/infrared wide angle viewing system and the radial neutron camera. This paper gives an overview of the major technical achievements on these two diagnostics and points out the urgent needed R&D activities. [Copyright &y& Elsevier]

The EUROfusion materials research program for DEMO in-vessel components aligns with the European Fusion Roadmap and comprises the characterization and qualification of the in-vessel baseline materials EUROFER97, CuCrZr and tungsten, advanced structural and high heat flux materials developed for risk mitigation, as well as optical and dielectric functional materials. In support of the future engineering design activities, the focus is primarily to assemble qualified data to supply the design process and generate material property handbooks, material assessment reports, DEMO design criteria and material design limits for DEMO thermal, mechanical and environmental conditions. Highlights are provided on advanced material development including (a) steels optimized towards lower or higher operational windows, (b) heat sink materials (copper alloys or composites) and (c) tungsten based plasma facing materials. The rationale for the down-selection of material choices is also presented. The latter is strongly linked with the results of neutron irradiation campaigns for baseline material characterization (structural, high heat flux and functional materials) and screening of advanced materials. Finally, an outlook on future material development activities to be undertaken during the upcoming Concept Design Phase for DEMO will be provided, which highly depends on an effective interface between materials' development and components' design driven by a common technology readiness assessment of the different systems. [ABSTRACT FROM AUTHOR]