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[en] Atmospheric H2S was measured by a fluorometric method (sensitivity 10 ng). In France, for aerated soils the emissions were between 0.8 and 27 μg m-2 h-1 H2S (average 5 μg m-2 h-1). The soil temperature is an important factor governing this emission. The H2S concentrations in the air ranged from 0.017 to 0.17 μg m-3 (average 0.080 μg m-3). In the Ivory Coast the H2S emissions were estimated between 30 and 300 μg m-2 h-1. The measured concentrations of H2S in the air at ground level ranged from 0.10 to 8.7 μg m-3. The relative importance of the measured emissions for anoxic soils of the humid equatorial forests in the global S cycle is discussed
Journal
Journal of Geophysical Research; ISSN 0022-1406; 
; v. 85(C8); p. 4468-4474
; v. 85(C8); p. 4468-4474
[en] The Tore Supra lower hybrid (LH) control system has been in operation for 10 years. Although its control system has given excellent service, it is an ageing system, and incompatible with many modern components and techniques. Hence, in order to improve the LH system's reliability, efficiency, compatibility and visibility, a new design of its control system was undertaken. A solution based on modern programmable logic controller coupled with a fast logic hardware 'state machine' has been selected as a replacement. This can handle the 'state diagram' and associated safety interlock functions for each klystron with the required time response. This paper presents the association of this state machine for fast control with the PLC for slow control, a PC based human interface, and all the control and process diagnostic functions which complete this Tore Supra LH control and security system
Journal
[en] The problem of desertification in Africa incites to materialize the circuit of the water vapour between its main source, the Gulf of Guinea, and its precipitation site. Some rainwater samples have been collected in Ouagadougou in 1975 and 1976 during the rainy season. The dosage of the stable isotopes D and O18 and radioactive isotope T shows that in 1975, a year with a general rain deficit, the rain was formed in a continental air mass. On the contrary, in 1976, a year with excess rain, the rain was formed in a maritime air mass. A study of the wind flows at 600, 900, 1500 and 2100 m shows that in 1975 the monsoon penetration is limited to the bottom of the Gulf of Guinea facing Cameroons, while in 1976 it entered the African Continent through the whole Gulf Coast, from Senegal to Cameroons. In 1976, the monsoon went up in latitude 30 to 50 more to the north than in 1975
[fr]
Le probleme de l'extension des zones desertiques du continent africain incite a materialiser le circuit suivi par la vapeur d'eau entre sa source principale, le golfe de Guinee, et son lieu de precipitation. Des echantillons d'eau de pluie ont ete collectes a Ouagadougou en 1975 et 1976 sur l'ensemble de la saison des pluies. Le dosage des isotopes stables D et O18 et radioactif T montre qu'en 1975, annee generalement deficitaire en pluie, celle-ci s'est formee dans une masse d'air a caractere continental. Par contre en 1976, annee excedentaire en pluie, celle-ci s'est formee dans une masse d'air a caractere maritime. Une etude des flux de vent a 600, 900, 1500 et 2100 m montre qu'en 1975 la penetration de la mousson est limitee au fond du golfe de Guinee face au Cameroun, tandis qu'en 1976, elle penetre sur le continent africain par l'ensemble de la cote du golfe, depuis le Senegal jusqu'au Cameroun. En 1976, la mousson remonte en latitude 3 a 5 degres plus au nord qu'en 1975Journal
Journal de Recherches Atmospheriques; ISSN 0021-7972; ; v. 13(1); p. 63-71
; v. 13(1); p. 63-71
[en] The Tore Supra Cryoplant is a vital and integral part of the experiment. It operates fully automatically and has been built for maximum specific operation for a tokamak. It includes over ten operating modes in order to save energy outside of plasmas operations. The present control system 'Architecture 7' is based on distributed Intel 8086 microprocessors. It includes over 1300 digital and 950 analogue input/output (I/O) cards. It has given excellent service for 10 years but difficulties of faultfinding, replacement of components and ageing circuit boards have degraded now the reliability of the cryosystem. Consequences of failures, faults and malfunctions might vary between some experimental hours lost to damage of some plant components. Cost maintenance and growing difficulties dictated an upgrade
Journal
[en] A source of polarized electrons based on a helium flowing afterglow has been developed at Orsay. This source, SELPO-M, has been placed on a 100 kV platform and set up in such a way as to allow its connection to the MAMI accelerator. Its performances in terms of current, polarization and optical properties are given. Its figure of merit (IP2≅75 μA) appears highly competitive as compared to strained GaAs sources. (author)
Journal
Nuclear Instruments and Methods in Physics Research. Section A, Accelerators, Spectrometers, Detectors and Associated Equipment; ISSN 0168-9002; ; CODEN NIMAER; v. 435(3); p. 271-283
; CODEN NIMAER; v. 435(3); p. 271-283
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