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71.
N. N. Ambraseys 《Journal of Seismology》1997,1(3):289-299
In this paper we assess the size and effects of the earthquakes of 12 May 1866, and 24 January 1916 in Anatolia (Turkey). We show that these events had a magnitude Ms 7.2 and that the former was associated with a 45-km long surface fault break along the north-east part of the East Anatolian Fault Zone. These two earthquakes are chosen among others in order to demonstrate how easy it is to miss out large earthquakes of the historical, even of the early instrumental period, and to draw the incompleteness of many existing catalogues to the attention of those who use them for the estimation of slip rates and the assessment of seismic hazard. Of the two earthquakes studied here, the former was only vaguely known and the latter is not included in Gutenberg and Richter's catalogue. 相似文献
72.
The evolution of views and practical decisions regarding the problem of collecting payment for the use of surface waters with regard to their quality in the former USSR and present-day Ukraine is discussed. A simple and feasible method is proposed for differentitation of regional (basin) rates of payment for the use of surface water in Ukraine with allowance made for its quality assessed based on a system of environmental classifications. 相似文献
73.
The paper presents the first quantitative results of a laboratory study of the velocity field in a two-arm spiral-wave pattern generated in a steady-state fashion by a hydrodynamical instability in a differentially rotating, thin layer of liquid. The liquid layer has a free surface, and the rotational profile includes an interval where the velocity drops abruptly, as in the gaseous disks of spiral galaxies. The properties of anticyclonic vortices observed between the arms of this pattern at the corotation radius are considered. 相似文献
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78.
Sensitivity kernels for finite-frequency surface waves 总被引:1,自引:1,他引:1
79.
M. Narayanasamy D. Dhanasekaran G. Vinothini N. Thajuddin 《International Journal of Environmental Science and Technology》2018,15(1):119-132
Printed circuit boards contain precious metals. They are produced in large volumes, rendering them an important component of the electronic waste. In view of the heterogeneity of the metals present, reprocessing of electronic waste is a heinous task. The present study focused on leaching of valuable metals from electronic waste printed circuit boards using Aspergillus niger DDNS1. The adaptation phases began at 0.1, 0.5 and 1.0% of fine powder of printed circuit boards with 10% inoculum and were optimized with three effective factors, viz. initial pH, particle size and pulp density, to achieve the maximum simultaneous recovery of the valuable metals. The interactions of these metals were also deciphered using scanning electron microscopy, energy-dispersive X-ray spectroscopy, X-ray diffraction, Fourier transform infrared spectrum and atomic absorption spectroscopy. The results indicated that extraction of the precious metals was accomplished mainly through the unique organic acids originating from A. niger DDNS1. The initial pH played an important role in the extraction of the precious metals and the metals precipitate formation. The leaching rate of the metals was generally higher at low powder dosage of printed circuit boards. The toxicity of the printed circuit boards had little effect on two-step bioleaching at the pulp density of 0.1% compared to one-step bioleaching. The two-step bioleaching process was followed under organic acid-forming conditions for the maximum mobilization of metals. Thus, the precious metals from printed circuit boards could be mobilized through fungal bioleaching which promises an important industrial application in recycling of electronic wastes. 相似文献
80.
N. Boneff 《Astronomische Nachrichten》1977,298(3):185-186
There are two fundamental conceptions concerning the laws of nature — these laws are eternal or they may vary in the course of time. We suggest an experiment in order to find an intermediary thesis — i.e. to discover that law, if it really exists, according to which a given law of nature varies, or, at least, to find out the direction in which this variation is performed. 相似文献