Elevated atmospheric CO2 concentration ameliorates effects of NaCl salinity on photosynthesis and leaf structure of Aster tripolium L.

This study investigated the interaction of NaCl-salinity and elevated atmospheric CO2 concentration on gas exchange, leaf pigment composition, and leaf ultrastructure of the potential cash crop halophyte Aster tripolium. The plants were irrigated with five different salinity levels (0, 25, 50, 75, 100% seawater salinity) under ambient and elevated (520 ppm) CO2. Under saline conditions (ambient CO2) stomatal and mesophyll resistance increased, leading to a significant decrease in photosynthesis and water use efficiency (WUE) and to an increase in oxidative stress. The latter was indicated by dilations of the thylakoid membranes and an increase in superoxide dismutase (SOD) activity. Oxidative stress could be counteracted by thicker epidermal cell walls of the leaves, a thicker cuticle, a reduced chlorophyll content, an increase in the chlorophyll a/b ratio and a transient decline of the photosynthetic efficiency. Elevated CO2 led to a significant increase in photosynthesis and WUE. The improved water and energy supply was used to increase the investment in mechanisms reducing water loss and oxidative stress (thicker cell walls and cuticles, a higher chlorophyll and carotenoid content, higher SOD activity), resulting in more intact thylakoids. As these mechanisms can improve survival under salinity, A. tripolium seems to be a promising cash crop halophyte which can help in desalinizing and reclaiming degraded land

Investigation of Losses in Fingers and Clamping Plates of High-Power Electrical Machines

International audienceWhen designing an electrical machine, the lossesin end-regions are often neglected or approximated withempirical equations due to the complexity of the involvedphysical phenomena and the difficulty to measure them. As aconsequence, important differences can appear between the totalmeasured losses and the value predicted by the analytic tools.This error can result in a high economic loss for machinemanufacturers. This paper presents a 3D FEM eddy current losscalculation in fingers and clamping plates of an experimentalbench set up. The study focuses on the effect of the axialcomponent of the flux density at the end region on these losses inthe case of different materials and power supply frequencies.Simulations results are presented and analyze

Eddy current computation in 2D-FEM for permanent magnet loss calculation

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Détermination des pertes harmoniques dans les aimants permanents. Cas des machines synchrones a aimants déposés

International audienc

Eddy current computation in 2D-FEM for permanent magnet loss calculation

International audienc

Effect of Industrial Impregnation Process on the Magnetic Properties of Electrical Steels

International audienceThis paper deals with the experimental investigation of the effect of impregnation process on the normal magnetization curve and iron losses of electrical steels. To address this issue, several laminated toroidal magnetic circuits have been designed to characterize the magnetic properties with the flux metric method. The first configuration considers magnetic circuits wrapped with adhesive tape so that the dielectric resin will be deposited only on the outer surface of the magnetic circuit. In the second configuration, the magnetic circuits are unwrapped, which will allow the resin to diffuse within the inter-laminar spaces of the magnetic circuit. The obtained experimental results show significant effects on the magnetic properties in both cases. However, depending on the considered configuration, the resin diffusion also has an influence on the changes in magnetic properties