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Raman spectroscopy is an efficient technique for studying the evolution of microstructure of materials under irradiation. For that purpose, a Raman spectrometer has been recently installed at the JANNUS-Saclay platform. In this paper, we describe the new setup for in situ experiments. These in situ experiments allowed following the microstructural evolution of different materials (SiC, ZrO2 and B4C) as a function of ion fluence on a single sample (either single crystal or polycrystalline ceramics) under the same irradiation conditions. Our results show that Raman spectroscopy is a versatile non-contact technique for studying on-line crystalline phase changes or amorphization of irradiated iono-covalent solids. A detailed analysis of Raman spectra is provided for the three materials (SiC, ZrO2 and B4C) investigated in this study, revealing quite different behaviors upon irradiation. Basically, Raman spectroscopy gives insight on these evolutions at the level of bonds given by specific phonon modes, in good agreement with Rutherford backscattering channeling (RBS/C), X-ray diffraction (XRD) or transmission electron microscopy (TEM) data, which provide information at a long-range scale. Copyright © 2015 John Wiley & Sons, Ltd.

International audience; Chromium-coated zirconium alloys are being studied as Enhanced Accident Tolerant Fuel Cladding for Light Water Reactors (LWRs). Those materials are especially studied to improve the oxidation resistance of LWRs current fuel claddings in nominal and at High Temperature (HT) for hypothetical accidental conditions such as LOss of Coolant Accident. Beyond their HT behavior, it is essential to assess the materials behavior under irradiation. A first generation chromium/Zircaloy-4 interface was thus irradiated with 20 MeV Kr$^{8+}$ ions at 400°C up to 10 dpa. High-Resolution Transmission Electron Microscopy and chemical analysis (EDS) were conducted at the Cr/Zr interface. The atomic structure of the interface reveals the presence of Zr(Fe, Cr)$_2$ Laves phase, displaying both C14 and C15 structure. After irradiation, only the C14 structure was observed and atomic row matching was preserved across the different interfaces , thus ensuring a good adhesion of the coating after irradiation.

The Oxide Dispersion Strengthened (ODS) materials are potential candidates as cladding tubes for Sodium-cooled Fast Reactors. The nano-oxides are finely dispersed within the grains and confer excellent mechanical properties to these alloys. Hence, assessing nano-particle stability under irradiation remains crucial to guarantee safe use of these materials. Although neutron irradiation remains a binding and challenging experimental study to conduct, difficulties can be overcome by ion beam processing. Ion beam processing of the ODS material allows to identify the radiation-induced Ostwald ripening as the mechanism governing the nano-particle response under irradiation. The result is the increase in size and a decrease in density of the finely dispersed Y2Ti2O7 nano-particles. Under neutron irradiation, radiation-induced Ostwald ripening appears to be less effective since a slight growth of nano-particles is observed. Further, our approach shows that nanoparticle growth kinetics should scale as φ1/3, φ being the radiation flux. This suggests that the low irradiation flux is at the origin of the slower growth kinetics of the neutron irradiated particles. Both neutron and ion irradiation induce a modification of the nanoparticles/matrix interfaces which are generally flat and sharp prior to irradiation and present steps after irradiation. This could alter the nano-particle coarsening during irradiation.

JANNUS (Joint Accelerators for Nanosciences and Nuclear Simulation), the unique triple beam facility in Europe, offers the possibility to produce three ion beams simultaneously for nuclear recoil damage and implantation of a large array of ions for well-controlled modeling-oriented experiments. The first triple beam irradiation was performed in March 2010. Along with irradiation developments, continuous efforts have been made to implement ex situ and in situ characterization tools. In this study, we set out the present status of the JANNUS facility of the Saclay site. We focus on the instrumentation used for conducting multi-ion beam irradiations and implantations as well as for characterizing bombarded samples. On-line control of irradiation parameters, in situ modification monitoring using Raman spectroscopy or ion beam induced luminescence, and ex situ characterization by ion beam surface analysis [Rutherford backscattering spectrometry (RBS), nuclear reaction analysis (NRA), and elastic recoil detection analysis (ERDA)] of implanted samples are detailed. Some examples of single, dual, and triple beam irradiation configurations are presented. Access to the facility is provided by the French network EMIR for national and international users ( http://emir.in2p3.fr/ ).

The third accelerator of the multi-ion irradiation platform JANNUS (Joint Accelerators for Nanosciences and NUclear Simulation), a 6SDH-2 Pelletron from National Electrostatic Corporation, Middleton was installed at Saclay in October 2009. The first triple beam irradiation combining Fe, He and H ion beams has been performed in March 2010. In the first part of this paper, we give a technical description of the triple beam facility, its performances and experimental capabilities. Typically, damage dose up to 100 dpa can be reached in 10 h irradiation with heavy ion beams, with or without simultaneous bombardment by protons, helium-4 ions or any other heavy ion beam. In the second part of this paper, we illustrate some IBA results obtained after irradiation and implantation experiments.

ODS materials constitute a new promising class of structural materials for advanced fission and fusion energy application. These Fe–Cr based ferritic steels contain ultra-high density of dispersion-strengthening nanoclusters conferring excellent mechanical properties to the alloy. Hence, guarantee the nanocluster stability under irradiation remain a critical issue. Nanoclusters are non-equilibrium multicomponent compounds (YTiCrO) forming through a complex nucleation pathway during the elaboration process. In this paper, it is proposed to observe the response of these nanoclusters when the system is placed far from equilibrium by means of ion beam. The results indicate that the Y, Ti, O and Cr atoms self-organized so that nanoclusters coarsened but maintain their non-equilibrium chemical composition. It is discussed that the radiation-sustained nanocluster metastability emerges from cooperative effects: radiation-induced Ostwald ripening, permanent creation of vacancies in the clusters, and fast Cr diffusion mediated by interstitials.

Multiple ion beam facilities have been used for nearly 30 years to simulate the irradiation effects of neutrons on relevant nuclear materials. Simultaneous ion beam irradiation allow the study of structural damage and foreign atoms accumulation in a broad range of parameters (projected range, temperature, dose rate, fluence, nuclear over electronic stopping power ratio) coupled with characterization of the investigated material. First, a review is given on the multi-irradiation facilities in operation worldwide. Then, the progress report of the Joint Accelerators for Nanosciences and NUclear Simulation project (JANNUS) is presented. In the third part of this paper, the main planned activity fields using JANNUS will be discussed i.e. the study of irradiation behaviour of nuclear materials, the controlled modification of materials properties by ion beam irradiation/implantation and the teaching of ion beam interactions with solids, ion beam physics and ion beam analysis.

International audience; Quantitative depth profiling measurements of implanted light elements is an important issue for electronics and nuclear applications. Conventional elastic recoil detection analysis (ERDA) has been improved by using heavy ions as incident particles for quantitatively profiling helium in materials.A new system has been implemented on the triple beam irradiation platform JANNUS at Saclay devoted to carry out HI-ERDA measurements. This device is dedicated to helium depth profiling using a 15 MeV 16O5+ incident ion beam. Capabilities of the technique (quantitative analysis, resolution and limit of detection) were tested on samples of known composition.For the first time, 4He depth profiles in pure α-iron, as-implanted and annealed, are obtained. HI-ERDA measurements have shown that helium release in pure α-iron can be described by a succession of two steps, the first having a slow kinetics below 700C and the second with a fast kinetics above 700C.

Oxide dispersion strengthened (ODS) ferritic steels are considered promising candidates as cladding tubes for Generation IV nuclear reactors. In such reactors, irradiation damage can reach more than 150 dpa at temperatures ranging from 400 to 650 degrees C. Thus nanopartide stability has to be guaranteed in order to ensure that these materials possess excellent creep properties. Using Fe ions, ODS steels were irradiated at 500 degrees C up to 150 dpa. At this temperature the nano-oxide population evolution under irradiation is similar to that observed after annealing at high temperature. It consists of a slight increase in the particle size and a slight decrease in the density, which can be both explained by an Ostwald ripening mechanism. Conversely, irradiations performed at room temperature using Au ions lead to a complete dissolution of the oxide particles, in agreement with the estimation of ballistic vs. radiation enhanced diffusion effects. (C) 2014 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

International audience; The SiC synthesis through single-beam of C+, and simultaneous-dual-beam of C+ & Si+ ion implantations into a Si substrate heated at 550 degrees C has been studied by means of three complementary analytical techniques: nuclear reaction analysis (NRA), Raman, and transmission electron microscopy (TEM). It is shown that a broad distribution of SiC nanoprecipitates is directly formed after simultaneous-dual-beam (520-keV C+ & 890-keV Si+) and single-beam (520-keV C+) ion implantations. Their shape appear as spherical (average size similar to 4-5 nm) and they are in epitaxial relationship with the silicon matrix. (C) 2013 Elsevier B.V. All rights reserved.

The third accelerator of the multi-ion irradiation platform JANNUS (Joint Accelerators for Nanosciences and NUclear Simulation), a 6SDH-2 Pelletron from National Electrostatic Corporation, Middleton was installed at Saclay in October 2009. The first triple beam irradiation combining Fe, He and H ion beams has been performed in March 2010 on a Fe-12Cr model ODS alloy. In the first part of this paper, we give a technical description of the triple beam facility. Then, we present its performances and experimental capabilities. Typically, damage dose up to 100 dpa can be reached in 10 hours irradiation with heavy ion beams, with or without simultaneous bombardment by protons, helium-4 ions or any other heavy ion beam. In the second part of this paper, we illustrate some recent experiments relative to advanced nuclear ceramics and composite materials developed in the frame of the Generation IV Forum research program or for fusion applications.

In addition to the previously known compound,7-oxo-16, 19-dihydroxy-3,4-dehydroclerodan-15,20 diacid-dilactone, two novel clerodane diterpenes have been isolated from the aerial portions of Baccharis articulata , namely, 8β-hydroxy-7-oxo- ent -cleroda-3-en-15,18-diacid-16,19-dilactone and 15,16-epoxy-7α,18-dihydroxy-15-methoxy- ent -cleroda-3-ene.

A new potently sweet labdane diterpene arabinoside, gaudichaudioside A (1), was isolated from the aerial parts of Baccharis gaudichaudiana DC. (Compositae). Also isolated were four other novel labdane arabinosides, gaudichaudiosides B–E (2–5), which although closely related to 1 structurally, were not found to be highly sweet.

International audience; The joint Accelerators for Nanosciences and NUclear Simulation project was started in 2002 in the frame of collaboration between CEA and CNRS. Due to the scientific skills developed for a long time, two experimental sites have been considered: (1) at Saclay, three electrostatic accelerators are being coupled, a new 3 MV Pelletron machine equipped with a multi-charged ion source, a 2.5 MV single ended Van de Graaff and a 2.25 MV tandem and (2) at Orsay, a 2 MV tandem and a 190 kV ion implanter are being coupled together with a 200 kV transmission electron microscope to allow simultaneous co-irradiation and observation. A brief review is first presented on multi-irradiation facilities available in the world. Then, a technical description of the new experimental facilities being installed is given. The main experiments we intend to carry out using mono, dual or triple irradiation configurations in different nuclear application fields and especially in the fusion domain will be further presented. (C) 2009 Elsevier B.V. All rights reserved.

The effect of Cuprofilin, a newly synthesized C.(II)-chlorophyll complex, was assessed in rats with experimental atherosclerosis. The study was focused on changes in serum cholesterol, lipids, and triglycerides concentration as well as on serum and abdominal aorta Cu and Zn values. It has been ascertained that after 90 d in animals fed a rich lipid diet there was a statistically significant increase in serum cholesterol, triglycerides, and lipid concentration (p < 0.01). A significant augmentation of serum Cu values (p < 0.01) accompanied by a marked lowering of the same element in abdominal aorta (p < 0.01) was also found, as compared to the results registered in the control group. However, Cuprofilin, administered for 90 d in the group of animals with experimental atherosclerosis, significantly decreased the serum cholesterol, triglycerides, and serum lipid values (p < 0.01), increased copper content in aortic tissue (p < 0.01) and lowered serum copper concentration (p < 0.01) as compared to the untreated group. Moreover, in the aorta of administered animals the lipid infiltration has been demonstrated to be significantly diminished vs the untreated group.

Serum copper concentration increases significantly (p

The authors followed up certain changes occurring at the level of the hypophysis-adrenal axis, during the development of experimental ulcers induced by pylorus ligature in rats treated with negative air ions. Previous experiments have shown that negative aeroionotherapy had a favourable influence on the prevention and evolution of gastric ulcers. The results of the present experiment showed that, under the influence of aeroionotherapy, the number of gastric ulcers/animal, and the relative weight of the adenohypophysis and of the adrenals glands decreased; the width of the fascicular zone of the adrenal cortex, and the volume of the cell nuclei in this fascicular zone also decreased.

A survey of the Compositae used in traditional medicine and as economic plants by Paraguayan country people was undertaken to identify the components of crude drugs traded by herbalists. Forty-five medicinal and economic species have been identified through field work in the rural areas and enquiries in the markets, as well as by examination of the literature in the Spanish language. Some crude drugs are shown to be mixtures of several closely-related species. The role of indigenous plant remedies within the local health care system is also discussed.

The mirid bugDicyphus tamaninii Wagner, is common in Catalonia in vegetable crops which have not been sprayed with insecticide. To study the feeding habits of this bug in tomato crops, several treated and untreated tomato plots were set up at Cabrils Experimental Station (North of Barcelona) during 1983, 1984 and 1985.

Zusammenfassung Aus den Samen von Holocalyx balansae Mich. wurde durch Chromatographie an Kieselgel Holocalin, ein neues cyanogenes Glykosid, isoliert. Holocalin wird durch Emulsin in Glucose, Cyanwasserstoff und m -Hydroxybenzaldehyd gespalten. Laut optischem Drehwert reprasentiert es das Diastercomere von Zierin.

The authors studied the influence of negative aeroionotherapy (AIT) on the gastric ulcer induced by pylorus ligature. After 24 hours the ligature was removed and the stomach was studied with respect to number and aspect of ulcers (hemorrhagic or not), periulcerous mucosa (edema, folds), acidity and microhemorrhage of gastric secretion. The animals were divided into 4 groups: C1 and C2 (controls)--not treated with air ions; P--prophylactically exposed 10 days before the operation to AIT; T--submitted to AIT prophylactically 10 days before the operation--therapeutically 5 days after operation. The results showed a favourable influence of AIT: the number of gastric ulcers was smaller; the regeneration processes in the mucosa were ameliorated; the gastric acid secretion and microhemorrhage diminished.