Design and Development of a Flexible Transmission Joint

A flexible joint made of high strength SS 510 HT steel adopted for handling some devices in radioactive environment has been re-designed in the context of the SPES project (Selective Production of Exotic Species) at the Istituto Nazionale di Fisica Nucleare (INFN, Legnaro (Padova, Italy)). The application is demanding since a 90° angle must be guaranteed in absence of lubricants and plastics components. Fatigue failures have occurred on the original component despite compliance with installation recommendations had been assured. Strain gauge acquisitions were first performed to measure the torque and the local stresses the joint undergoes in-service. After that, a large-displacement, non-linear finite element (FE) analysis was performed and numerical and experimental stresses acting on the joint were successfully compared. After validation, the FE model was used to re-design the joint in order to comply with the in-service fatigue life requirements and, at the same time, to avoid increasing the overall joint dimensions

Influence of steam sterilisation on soil chemical characteristics, trace metals and clay mineralogy

Soil sterilisation with steam under pressure and additives, such as CaO or KOH that react exothermically in water, is an alternative technology to fumigants. The influence of soil sterilisation (system dBioflashT, Ecoflash SC 600) on the chemical behaviour of organic matter, heavy metals (Cd, Cu, Zn and Pb) and clay mineralogy was investigated on three typical soil materials (Ap horizons) with different carbonate contents. These materials were treated in the laboratory in wooden containers. Soil heating produced temperatures ranging between 60–80 8C for at least 20 min. The treatment generally seemed to increase the pH values and may lead in the long-term to a certain alkalisation with high dosages of CaO or KOH. The effects of the CaO treatment on the K and Ca speciation in the soil were rather small, whereas those of the KOH treatment were more pronounced for K. The addition of KOH favoured the fixation of K in the interlayers of smectite. The XRD measurements were in agreement with the chemical speciation of K. The K chemistry was affected by the treatment by higher contents of the fixed fraction. Organic matter partially decreased after the soil heating treatment. The behaviour of the heavy metals was also affected. In some cases, the EDTA-extractable fractions of Cu, Zn or Pb as well as the soluble fractions of Cu and Zn were distinctly changed after the treatment. The soil-heating treatment probably affected the type and amount of organic ligands and also the adsorbing surfaces that control the solubility of the heavy metals. The heavy metal solubility, however, still remained low after the treatment. The effects of the soil sterilisation on the chemical and mineralogical properties did not seem to be dramatic. It is, however, difficult to predict possible changes if the treatment is repeated over years to decades. We presume that there might be quite substantial effects (especially on the behaviour of organic matter under certain circumstances) in the long term if, as seen at some sites, changes (i.e. decrease) are already measurable after one treatment. Mulching or the addition of organic manure would be possible measures to counter a destabilisation of the soil (i.e. increase in soil erosion susceptibility) and a continuous disintegration of the organic matter pool

Compte-rendu d'activite sur les derives pyridiniques R.P

CNRS AR 12980 (1-4) / INIST-CNRS - Institut de l'Information Scientifique et TechniqueSIGLEFRFranc