Metallurgical analysis and RF losses in superconducting niobium thin film cavities

Copper cavities with a thin niobium film as used in the large electron positron collider LEP would be also attractive for future linear colliders, provided the decrease of the Q-value with the accelerating gradient can be reduced. We aim at extracting the important parameters that govern this decrease. The dependence on the RF frequency is studied by exciting 500 MHz and 1500 MHz cavities in different modes. In addition we combined RF measurements for two 1500 MHz cavities of different RF performance with microscopic tests (AFM, TEM) on samples cut out of the same cavities. Their micro-structural characterisation in plan-view allows to extract the grain size and the defect densities

Giant Magnetoresistance - Schichten für Sensoren

von Loyen L, Hütten A, Reiss G. Giant Magnetoresistance - Schichten für Sensoren. SENSOR REPORT. 1997;12:28

The absence of antiferromagnetic coupling and GMR effect in evaporated permalloy/Cu multilayers, in situ transport properties

Lucinski T, Reiss G, Mattern N, van Loyen L. The absence of antiferromagnetic coupling and GMR effect in evaporated permalloy/Cu multilayers, in situ transport properties. JOURNAL OF MAGNETISM AND MAGNETIC MATERIALS. 1998;189(1):39-46.Thermally evaporated (permalloy Ni80Fe20)/Cu multilayers were deposited on to quartz glass substrate, oxidised Si and etched Si wafers at room temperature and at 100 K. The samples were examined during an evaporation process by means of in situ conductance measurements whereas magnetisation, X-ray diffraction, atomic force microscopy and the cross-section electron transmission microscopy were performed ex situ to characterise our samples. Only a very small GMR effect was observed for samples deposited at RT and at 100 K. An absence of the antiferromagnetic coupling seems to result from the large interface roughness. Multilayers deposited at 100 K showed the existence of a highly topological disordered alloy-like structure formed during the deposition process. (C) 1998 Elsevier Science B.V. All rights reserved

Bilan de la qualité radiologique des eaux du robinet 2008-2009

Un bilan de la qualité radiologique des eaux du robinet a été réalisé par l’Autorité de sûreté nucléaire (ASN), la Direction générale de la santé (DGS) et l’Institut de radioprotection et de sûreté nucléaire (IRSN) sur la base principalement des résultats obtenus dans le cadre du contrôle de la qualité radiologique des eaux de distribution publique (ou eaux du robinet). Ce bilan montre que le contrôle est désormais opérationnel sur l’ensemble du territoire français et que la qualité radiologique est globalement satisfaisante, puisque 99,8 % de la population a été alimentée par une eau pour laquelle la dose totale indicative (DTI) respectait en permanence les niveaux fixés par la réglementation. La présence d’uranium a été mesurée par l’IRSN sur 360 échantillons d’eau pour lesquels l’activité alpha globale était supérieure à 0,1 Bq/L ; 3,1 % d’entre eux dépassaient la valeur guide (30 µg.L-1) recommandée par l’Organisation mondiale de la santé pour tenir compte de la toxicité chimique de ce paramètre. À ce niveau de concentration, la présence d’uranium ne présente pas d’enjeu radiologique. Par ailleurs, un bilan historique relatif à la présence de radon-222 dans les ressources en eau utilisées pour la production d’eau du robinet a mis en évidence que 4 % des mesures étaient supérieures à 1 000 Bq.L-1, valeur à partir de laquelle la Commission européenne recommande de mettre en place des actions correctives

Pb and

The data on 210Pb and 210Po activities in French foodstuffs acquired during the last 15 years are numerous enough to derive reference values which will be usable to assess the dose to the French population due to the intake of these two natural radionuclides. The means and ranges are close to those observed in various countries and are most often higher than the reference values proposed by UNSCEAR. Mussels and oysters exhibit the highest 210Po activities of all kinds of foodstuffs, with a mean value of 27 Bq.kg-1 fresh weight , followed by crustaceans and small fish species (anchovies, mullets, sardines, etc.) with 210Po activities in the order of 3 to 10 Bq.k-1 fresh weight; cephalopods and other fish species presenting activities around 1 to 3 Bq.kg-1 fresh, close to the UNSCEAR reference value. Below these highest 210Po activities are those of 210Po and 210Pb in terrestrial kinds of foodstuffs, by decreasing order: meats (around 1 Bq.kg-1 fresh), cereals (0.4 Bq.kg-1), leafy vegetables (0.3 Bq.kg-1), other vegetables and fruits (0.1 Bq.kg-1), and milk (from 0.03 to 0.1 Bq.L-1)