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211.
M. Bouchon S. Gaffet C. Cornou M. Dietrich J.P. Glot F. Courboulex A. Caserta G. Cultrera F. Marra R. Guiguet 《Journal of Seismology》2000,4(4):517-523
We found extensive evidence that the vertical ground accelerations produced during the largest shock (M = 6.0) of the 1997 Umbria-Marche earthquake sequence exceeded 1g in two areas close to the heavily-damaged villages of Annifo and Colle Croce. This evidence comes from the striking observation of thousands of freshly fractured and broken rocks and stones in these areas. Some of the broken stones lie isolated on soft detritic soil while others had been previously piled up, probably a long time agoto clear the fields for farming. The freshness of the cuts and fractures and the consistency of the observations for thousands of rocks and stones in these areas indicate that these rocks were thrown upwards during the earthquake, with breakage occurring at the time of impact. Ground motion calculations consistent with the static deformation inferred from GPS and interferometry data, show that the broken stones and rocks are found in the zone where the strongest shaking took place during the earthquake and that most of the shaking there was vertical. 相似文献
212.
A simple and general technique to obtain a six-component earthquake input motion of a rigid foundation using three-linear-components earthquake record is presented. Using the multicomponent input, the maximum structural response to an arbitrarily oriented earthquake is derived. The method is applied to determine the response spectrum for a two-d.o.f. laterally and torsionally coupled linear system. The effects of foundation geometry, structural properties and apparent wave velocity on the structural response are investigated. It is found that increasing the foundation size reduces the peak values of the input motion; this reduction is more pronounced for a square foundation than for a circular one. 相似文献
213.
D. J. Stom S. S. Timofeeva N. F. Kashina L. J. Bielykh S. N. Souslov V. V. Boutorov M. S. Apartzin 《洁净——土壤、空气、水》1980,8(3):203-211
By the example of some phenols and qninones, in aqueous solutions possibilities for the quantitative determination are tested separately and in the mixture. Methods for thin-layer chromatography and spectrophotometry were developed. There can be chromatographically deteeted between 5 and 80 μg of substance. Phenol and quinone concentrations of 1.5 · 10?3 … 0.5 · 10?4 M were spectrophotometrically investigated. 相似文献
214.
J.F. Payne 《Marine pollution bulletin》1977,8(5):112-116
Several phyla from the coastal Northwest Atlantic were investigated for mixed function oxidases. Enzyme activity was related to petroleum hydrocarbon metabolism and detection in the marine environment. 相似文献
215.
216.
F. Zebender P. Zimmermann R. Märki A. Hörler H. Ambübl 《Aquatic Sciences - Research Across Boundaries》1961,23(1):296-308
Ohne Zusammenfassung 相似文献
217.
218.
Ohne Zusammenfassung 相似文献
219.
Paul R. Renne Alan L. Deino Willis E. Hames Matthew T. Heizler Sidney R. Hemming Kip V. Hodges Anthony A.P. Koppers Darren F. Mark Leah E. Morgan David Phillips Brad S. Singer Brent D. Turrin Igor M. Villa Mike Villeneuve Jan R. Wijbrans 《Quaternary Geochronology》2009,4(5):346-352
Data reported in 40Ar/39Ar geochronology studies are commonly insufficient to allow computation of ages. This deficiency renders it difficult to compare ages based on different standards or constants, and often hinders critical evaluation of the results. Herein are presented an enumeration of the data that should be reported in all 40Ar/39Ar studies, including a discussion in support of these requirements. The minimum required data are identified and distinguished from parameters that are useful but may be derived from them by calculation. Finally, recommendations are made for metadata needed to document age calculations (e.g., from age spectrum or isochron analyses). 相似文献
220.
The manner in which the dynamics of geoelectric earth inhomogeneities can be studied using receiving lines oriented in different directions at a single site is considered. It is shown that the presence of a local geoelectric inhomogeneity allows monitoring the state of electric conductivity in the earth by observation of the telluric tensor. We quote results from long-continued monitoring of the electrotelluric tensor in Kamchatka. The tensor’s behavior showed an appreciable anomaly, which may have been related to great (magnitude 8.2 and 8.3) earthquakes in the Kuril-Kamchatka region. 相似文献