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Embedded RF contacts are integrated within the ITER ICRH launcher to allow assembling, sliding and to lower the thermo-mechanical stress. They have to withstand a peak RF current up to 2.5 kA at 55 MHz in steady-state conditions, in the vacuum environment of themachine.The contacts have to sustain a temperature up to 250{\textdegree}Cduring several days in baking operations and have to be reliable during the whole life of the launcher without degradation. The RF contacts are critical components for the launcher performance and intensive R&D is therefore required, since no RF contactshave so far been qualified at these specifications. In order to test and validate the anticipated RF contacts in operational conditions, CEA has prepared a test platform consisting of a steady-state vacuum pumped RF resonator. In collaboration with ITER Organization and the CYCLE consortium (CYclotronCLuster for Europe), an R&D program has been conducted to develop RF contacts that meet the ITER ICRH launcher specifications. A design proposed by CYCLE consortium, using brazed lamellas supported by a spring to improve thermal exchange efficiency while guaranteeing high contact force, was tested successfully in the T-resonator up to 1.7 kA during 1200 s, but failed for larger current values due to a degradation of the contacts. Details concerning the manufacturing of the brazed contacts on its titanium holder, the RF tests results performed on the resonator and the non-destructive tests analysis of the contacts are given in this paper., Comment: Fusion Engineering and Design, Elsevier, 2015, Available online 21 April 2015

Actively cooled plasma facing components (PFCs) have to exhaust high heat fluxes from plasma radiation and plasma–wall interaction. Critical heat flux (CHF) event may occur in the cooling channel due to unexpected heat loading or operational conditions, and has to be detected as soon as possible. Therefore it is essential to develop means of monitoring based on precursory signals providing an early detection of this destructive phenomenon, in order to be able to stop operation before irremediable damages appear. Capabilities of CHF early detection based on acoustic techniques on PFC mock-ups cooled by pressurised water were already demonstrated. This paper addresses the problem of the detection in case of flow rate reduction and of flow dilution resulting from multiple plasma facing units (PFU) which are hydraulically connected in parallel, which is the case of ITER divertor. An experimental study is launched on a dedicated mock-up submitted to heat loads up to the CHF. It shows that the measurement of the acoustic waves, generated by the cooling phenomena, allows the CHF detection in conditions similar to that of the ITER divertor, with a reasonable number of sensors. The paper describes the mock-ups and the tests sequences, and comments the results.

Plasma facing components (PFCs) with tungsten (W) armor materials for DEMO divertor require a high heat flux removal capability (at least 10 MW/m2 in steady-state conditions). The reference divertor PFC concept is a finger with a tungsten tile as a protection and sacrificial layer brazed to a thimble made of tungsten alloy W – 1% La2O3 (WL10). Defects may be located at the W thimble to W tile interface. As the number of fingers is considerable (>250,000), it is then a major issue to develop a reliable control procedure in order to control with a non-destructive examination the fabrication processes. The feasibility for detecting defect with infrared thermography SATIR test bed is presented. SATIR is based on the heat transient method and is used as an inspection tool in order to assess component heat transfer capability. SATIR tests were performed on fingers integrating or not the complex He cooling system (steel cartridge with jet holes). Millimeter size artificial defects were manufactured and their detectability was evaluated. Results of this study demonstrate that the SATIR method can be considered as a relevant non-destructive technique examination for the defect detection of DEMO divertor fingers.

For steady state (magnetic) thermonuclear fusion devices which need large power exhaust capability and have to withstand heat fluxes in the range 10–20 MW m−2, advanced Plasma Facing Components (PFCs) have been developed. The importance of PFCs for operating tokamaks requests to verify their manufacturing quality before mounting. SATIR is an IR test bed validated and recognized as a reliable and suitable tool to detect cooling defaults on PFCs with CFC armour material. Current tokamak developments implement metallic armour materials for first wall and divertor; their low emissivity causes several difficulties for infrared thermography control. We present SATIR infrared thermography test bed improvements for W monoblocks components without defect and with calibrated defects. These results are compared to ultrasonic inspection. This study demonstrates that SATIR method is fully usable for PFCs with low emissivity armour material.

For ITER divertor Plasma Facing Components (PFCs), tens of thousands of armor/heat sink interfaces will be produced by the industry. Statistically, there is a probability that interfaces with defects be delivered. The defect detection with Non Destructive Techniques (NDT) is then a major challenge. NDT should provide a detectability threshold below the critical defect size. For a defect located all along the axial length of a component, the critical defect size at interface is about 50° for W monoblock (resp. 6 mm for W flat tile). It is defined with thermo-mechanical fatigue behaviour under 10 MW m−2 for W monoblock (resp. 5 MW m−2 for W flat tile). The purpose of this paper is to study the armor/heat sink defect detection of tungsten components (flat tile and monoblock geometries) with SATIR test bed (Infrared thermography NDT). We demonstrate that SATIR is a relevant NDT to detect defect of W components.

Thermal fatigue behaviour of repaired monoblocks was assessed from High Heat Flux (HHF) tests up to 20 MW m−2 on 11 components. Among these components, 8 monoblocks were repaired (2 CFC and 6 tungsten). These components were manufactured by two EU industries: ANSALDO Ricerche and PLANSEE. Non destructive examination was performed on SATIR thermography test bed before and after HHF tests. SATIR results show that repaired monoblocks have a good thermal exhaust capability before HHF tests. For all monoblocks, no degradation of thermal properties was noticed during cycles at 10 MW m−2. After hundreds of cycles at 20 MW m−2, two W repaired monoblock melted. Post-HHF SATIR examination revealed a degradation of thermal properties which is systematic for W melted monoblocks and non-systematic for W repaired ones. For CFC repaired monoblocks, no damage was observed up to 20 MW m−2. For the first ITER divertor set, specifications for the pre-qualification are that CFC (Resp. W) components have to sustain in steady state 1000 cycles at 10 MW m−2 (Resp. 3 MW m−2) followed by 1000 cycles at 20 MW m−2 (Resp. 5 MW m−2). For the first ITER divertor set, the repair process is validated for CFC and W monoblocks.

High heat flux loaded components which will be installed in the ITER Divertor require a heat flux removal capability in the range 5–10 MW/m2 at steady-state and up to 20 MW/m2 in transients. Within the ITER plasma facing components procurement context, each party should demonstrate its technical capability to carry out the manufacturing with the required quality. This is achieved through the successful manufacturing and testing of medium-size qualification prototypes. Each Qualification Prototype consists of three high heat flux units mounted onto an actively cooled supporting structure. Currently, the SATIR method has been identified by the ITER Organization as the basic test to decide upon the final acceptance of the ITER Divertor components. SATIR testing was performed on each CFC part of European HHF units prior to the insertion of the twisted tape and prior to assembling the units onto the steel support structure. The paper deals with SATIR results of all qualification prototypes manufactured by European industry.

Tens of thousands of armor/heat sink joints will be produced by the industry during the manufacturing of ITER divertor PFC, statistically, there is a probability that joints with defects be delivered. The purpose of this paper is to study the detection and evolution during operation of calibrated defects artificially implemented on samples, as an experimental basis for the definition of acceptance criteria for the bond armor/heat sink in the frame of industrial manufacturing conditions.It was found that current CFC monoblock design option was compatible with the heat loads specified at the lower part of the vertical target (up to 20 MW/m2), including the presence of armor/heat sink defects (up to 50° extension for a location at 0° or 45°) detectable with NDE techniques developed in Europe (US, SATIR). The current W monoblock design appeared suitable for the upper part of the vertical target with defects extension up to 50°, but is not adapted for heat flux of 20 MW/m2. The studied W flat tile design proved to be compatible with fluxes of 5 MW/m2 but unable to sustain cycling fluxes of 10 MW/m2.

The TF magnetic system of the international thermonuclear experimental reactor (ITER) will be composed of 18 superconducting coils assembled in a torus. The design of these large coils relies on the use of a circular cable-in-conduit conductor (CICC) composed of a cable of about one thousand twisted Nb3Sn and copper strands embedded in a thin steel jacket. The different thermal contractions of the materials composing this conductor during the cool down from the Nb3Sn heat treatment reaction temperature (about 920 K) to the operating temperature (about 5 K) result in a compressive strain on the superconducting Nb3Sn filaments which leads to a degradation of the conductor critical current. The qualification of the ITER conductor prototypes will be performed by testing short straight full size samples in the unique European test facility SULTAN at PSI (Switzerland). A comparison of the performance of the toroidal field model coil (TFMC) conductor in a short straight sample and in the coil has shown indications that the sample performance is better, apparently because the thermal strain in Nb3Sn is lower. It looks possible that this could have been caused by a slippage between the cable and the jacket in the joints at the sample ends during the heat treatment. In this case, these kind of short straight samples could not be relevant for conductor qualification. An investigation on the thermal strain by destructive examination of different TFMC conductor samples, including one leg of the TFMC short sample tested in 1999 in the SULTAN facility, was performed at CEA Cadarache. The paper reports on the different strain measurements, proposes an analytical approach of the results in order to conclude on the relevance of straight samples.

The objective of this study was to compare the clinical and bacteriologic efficacy and safety of cefodizime 1 g intramuscularly (IM) once daily (group A) versus cefodizime 1 g IM twice daily (group B) and versus ceftriaxone 1 g IM once daily (group C) in patients with community-acquired pneumonia. A total of 298 patients, affected by bronchopneumonia or pneumonia with known or suspected bacterial cause, new focal signs on examination of chest, and radiographic evidence of a recent infiltrate, were randomized in three comparable groups. The infection was rated as mild, moderate, or severe. A total of 283 patients were assessable for efficacy: 95 in group A, 94 in group B, and 94 in group C. Mean (+/- SD) duration of treatment was 5.96 +/- 1.39 days in group A, 6.24 +/- 1.57 days in group B, and 6.66 +/- 1.95 days in group C. Symptoms such as purulent sputum, cough, and dyspnea improved significantly after treatment in all groups; temperature normalized by about day 3. Clinical efficacy was rated good in 94.74% of patients in group A, in 92.55% in group B, and in 87.23% in group C. Positive bacteriologic cultures were obtained before treatment from 144 patients: bacteriologic responses were rated good in 98.11%, 98.08%, and 92.80% in groups A, B, and C, respectively. No significant differences were found between the three treatment groups for any measures of clinical efficacy. No serious adverse event occurred in any of the groups. We conclude that cefodizime 1 g IM once daily is an effective dosing regimen in the treatment of patients with community-acquired pneumonia.

For plasma-facing components (PFCs), carbon-fiber composite (CFC) armor material should have specific technical requirements. CFCs must have good mechanical and thermal properties suitable for the PFC manufacturing process, in-service needs and inspection requirements. Inspection after manufacturing and thermal behaviour under thermal fatigue loads of PFCs made of different CFC grades (N31, NB31, N11, NB41, DMS814, DMS780, Dunlop 3D and SGL Sigrabond) were studied. After manufacturing, all the components satisfied the acceptance criteria, and components manufactured with CFCs with the same fibers in the x- and y-directions have a better heat removal capability than components manufactured with CFCs with fibers different in the x- and y-directions. High heat flux-tested components endured correctly the thermal cycling (up to 1000 cycles at 20 MW m−2) without water leakage, but for a few monoblock tiles, depending on the CFC grade, erosion was observed.

The cytocidal activity of light-activated hematoporphyrin derivative (Hpd) in experimental and human tumors is under investigation in many laboratories. This activity is based upon preferential incorporation of Hpd in malignant tissues and its photosensibilization by red light. Treatment of mice bearing MS-2 fibrosarcoma and B 16 melanoma, a metastatic tumor, with Hpd and laser light, externally or delivered through a quartz fiber optic imbedded directly into the tumor, significantly prolonged the median survival time. This therapy was compared with surgical excision of primary tumors, and preliminary results on metastatic neoplasm suggest that the photoradiation therapy is more effective than surgery.

Équipe 107 : Physique des plasmas chauds; International audience; In parallel to the direct contribution to the procurement phase of ITER and Broader Approach, CEA has initiated research & development programmes, accompanied by experiments together with a significant modelling effort, aimed at ensuring robust operation, plasma performance, as well as mitigating the risks of the procurement phase. This overview reports the latest progress in both fusion science and technology including many areas, namely the mitigation of superconducting magnet quenches, disruption-generated runaway electrons, edge-localized modes (ELMs), the development of imaging surveillance, and heating and current drive systems for steady-state operation. The WEST (W Environment for Steady-state Tokamaks) project, turning Tore Supra into an actively cooled W-divertor platform open to the ITER partners and industries, is presented.