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A. Ya. Sidorin 《Seismic Instruments》2007,43(1):11-20
As a result of the analysis of both the monitoring data of the electric resistivity of the Earth’s crust at the Garm test site using a modified method of dipole sounding and the earthquake catalogue of this test site it is shown that annual periodicity exists not only in the variations of the electric resistivity of the Earth’s crust but also in seismicity. It is not clear yet whether the appearance of the annual periodicity in the variations of electric resistivity is related to the influence of the periodic processes of earthquake nucleation on this process or both processes are synchronized by a third, unknown process. The results of the investigation show that the annual component of time variations in the electric resistivity contains important information about the processes in the Earth’s crust and should not be filtered out but, in contrast, studied in detail. The joint analysis of periodic components in the compared time series of the electric resistivity of the Earth’s crust and earthquakes opens new possibilities for deeper understanding of the processes of seismicity genesis and for improving the methods of strong earthquakes prediction. 相似文献
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V. A. Pavlenov Ya. B. Radziminovich S. G. Arzhannikov A. S. Gladkov I. A. Dzyuba 《Journal of Volcanology and Seismology》2007,1(6):421-428
The present study is devoted to the assessment of shaking intensities due to the September 17, 2003, earthquake occurring in the Khoito-Gol basin (southwestern flank of the Baikal Rift System). The instrumental and macroseismic data used here were acquired during an investigation into the impact of this seismic event. The highest intensity of shaking, VI, was recorded at Khoito-Gol, the human settlement that was the nearest to the instrumental epicenter. A nonuniform distribution of intensity was found for different directions from the epicenter. A scatter of as much as two intensity units was recorded at one settlement. 相似文献
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攀枝花地区不同工业区表层土壤中重金属分布的特征 总被引:12,自引:0,他引:12
作者在本文中研究了攀枝花地区不同工业区表层土壤中重金属的污染特征及元素组合。结果表明,煤矿区以Cd,Ni,Cu,Zn污染为主,攀钢工业区以Ni,Cu,Cd, Cr污染为主,其它工业区以Cd,Ni污染为主。不同工业区的重金属元素组合特征基本一致,即分为As-Cd-Cu-Ni-Pb和Cr-Zn两组。 相似文献
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数据加密是信息科学中一个重要问题 ,它对于知识产权的保护、防止机密数据外流及情报的安全传递都有很重要的现实意义。文中提出一种利用图像携带加密数据的技术 ,将需要加密的数据隐藏到一幅图像文件中 ,而对宿主文件的效果影响甚微 ,并采用两种数据筛方法 ,即利用图像特征数据筛保持携密图像的带密位仍具有原始图像的特征 ,利用随机数筛消除加密数据的特征 ,从而有效地防止这类图像被识别与解密 ,为私有信息的存储与传递提供安全保障。 相似文献
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Gladyshev M. I. Gribovskaya I. V. Ivanova E. A. Moskvichova A. V. Muchkina E. Ya. Chuprov S. M. 《Water Resources》2001,28(3):288-296
Data of two field studies were used to analyze the concentrations of Na, K, Ca, Mg, Fe, Mn, Zn, Cu, Al, Cr, Ni, Cd, and Pb in the water, bottom deposits, zoobenthos, fish, and macrophytes of the Pond Bugach and in the soils near the pond. It was established that the majority of metals in the soils and bottom deposits correlate and their concentrations are governed by the universal geochemical factors of the region. The heavy metals were recognized that originate from anthropogenic sources and their concentrations were found to exceed the maximum admissible values for different components of the ecosystem. Five types of heavy metals migration were recognized in the soil–bottom deposits–zoobenthos–fish chain and in macrophytes. Statistically significant difference was found to exist between the concentrations of some heavy metals in the muscles of fish species with different food types (crucian carp and perch) as well as between the correlations of metals. The recorded concentrations were compared with the concentrations of metals measured in the last decade in other limnetic ecosystems in Siberia, Europe, North America, and China. 相似文献