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Trace pollutants analysis in soil by a time-resolved laser-induced breakdown spectroscopy technique 总被引:5,自引:0,他引:5
A. Ciucci V. Palleschi S. Rastelli R. Barbini F. Colao R. Fantoni A. Palucci S. Ribezzo H. J. L. van der Steen 《Applied physics. B, Lasers and optics》1996,63(2):185-190
The results of a joint experiment of IFAM-Pisa and ENEA-Frascati for the detection of traces of pollutants in soil by a time-resolved laser-induced spectroscopy technique are reported. Using samples of soil with known pollutants' concentration [Geochemical Exploration Reference (GXR) silicate from US Geological Survey], we were able to estimate the sensitivity of this Laser-Induced Breakdown Spectroscopy (LIBS) technique to be of the order of some parts per million for a vast class of metallic pollutants, including extremely dangerous soil pollutants such as copper, lead and chromium.ENEA guest with HC&M fellowship 相似文献
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This paper considers hypergraph communication situations, where for a group of agents the economic possibilities are described by a coalitional game and the communication possibilities are described by a hypergraph in which the nodes are the agents and the edges are the subgroups of agents who can effect communication. Axiomatic characterizations are provided for two allocation rules, the Myerson value and the position value. 相似文献
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A. A. van der Horst A. M. van der Kraan J. J. van Loef D. J. Lieftink C. Joosten 《Hyperfine Interactions》1994,91(1):613-618
Mössbauer spectroscopy has been applied to two rattle stones found in the Netherlands, which have been formed under different pedoenvironment conditions in the past. Ultrafine particles of goethite are dominantly present in both core and mantle of these stones. The latter differs in both composition and mean particle size; this is related to the distinct manner of their formation. 相似文献
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Boena N. Kolarz Maria Wojaczyska Jan Kaczmarczyk Teresa Siemieniewska Kazimierz Tomkw 《Journal of Polymer Science.Polymer Physics》1994,32(12):1977-1990
Sulfonic cation exchangers with two ion exchange group concentrations (0.5 and 2.4 mmol/g, samples A and B, respectively) were obtained by sulfonation of a porous styrene (S) and divinylbenzene (DVB) copolymer with chlorosulfonic acid. Strong thermal decomposition of the sulfonated copolymer A, accompanied by significant changes in its porous structure, starts at ca. 400°C. The char has no sulfonic groups. After heat treatment at 400°C in steam, a sorbent was obtained (yield 65%) that shows higher phenol sorption than the untreated sample when related to the bed volume. The chlorosulfonic derivatives of the initial copolymer were less thermally resistant than the sulfonic ones obtained by hydrolysis. Pyrolysis of the cation exchanger B, in its H+ and Ca2+ forms, was carried out at 900°C (yield of both chars close to 30%). By subsequent steam activation at 800°C to a 50% burn-off of the char, sorbents with well-developed, but distinctly different, porous structures were obtained. The activated char from the sulfonated copolymer in its hydrogen form was highly microporous and indicated an effective surface area of 1180 m2/g. However, because of a low contribution of mesopores, its ability to adsorb phenol from the liquid phase was not very high. The activated char from the calcium-doped copolymer, indicating a smaller surface area (580 m2/g) but characterized by a well-developed mesoporosity, was a better sorbent for phenol. © 1994 John Wiley & Sons, Inc. 相似文献