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951.
952.
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
953.
954.
This review generalizes the latest advances in the chemical synthesis of the plant growth regulators brassinosteroids in 1990–1994.Institute of Bioorganic Chemistry, Belarus Academy of Sciences, 220141, Minsk, ul. Zhodinskaya, 5/2. Translated from Khimiya Prirodnykh Soedinenii, No. 4, pp. 507–544, July–August, 1997. 相似文献
955.
L. A. Kurdanchenko B. V. Petrenko I. Ya. Subbotin 《Ukrainian Mathematical Journal》1997,49(11):1742-1746
We prove that, in an Artinian module, the upper FC-hypercenter over an infinite FC-hypercentral locally solvable group has a direct complement. Thus, we obtain a generalization of one of Zaitsev’s theorems and one of Duan’s theorems. 相似文献
956.
957.
V. A. Kosobukin 《Technical Physics》1998,43(7):824-829
An analytical theory of scanning near-field magnetooptical microscopy is developed. The theory is based on the elastic scattering
of light by small, resonantly polarizable particles, which are used to scan the plane surface of a nonuniformly magnetized
medium. The effective polarizability of the particles is calculated with the effect of dynamic “image forces” taken into account
in all orders of perturbation theory with respect to the interaction of the particle with a demagnetized ferromagnet, and
the magnetooptical perturbation is calculated to first order in the magnetization. The major contributions to the magnetooptical
light scattering for a ferromagnetic structure magnetized perpendicular to the surface are found, including a quasistatic
approximation for the near-field particle-magnet interaction. The optical size resolution of a magnetic (dielectric) inhomogeneity
is estimated.
Zh. Tekh. Fiz. 68, 86–91 (July 1998) 相似文献
958.
959.
Approximate method of calculating stresses in a rectangular plate locally loaded by a harmonic force
From double trigonometric series for bending moments the slowly converging components are picked out. When the loading facets are small compared with the width of the plate, they are approximately summed by the analytical method. This simplifies substantially the calculation of bending moments and stresses in the zone of small loading facets compared with the usual expansion with respect to the natural vibration forms.Translated from Teoreticheskaya i Prikladnaya Mekhanika, No. 20, pp. 84–88, 1989. 相似文献
960.