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L. Neupert 《洁净——土壤、空气、水》1986,14(2):109-119
Organohalogen compounds are gaining in importance in the control of surface and drinking water due to their unwholesome properties. An accumulation of the organohalogen compounds, occurring mostly at low concentrations, is possible in different ways. The author discusses the possibility and problems of the extractability from waters with the aid of organic solvents. The group parameter EOX that can be determined does not allow any statement concerning components of individual substances, but gives some clues to the state of surface and drinking waters which are mostly anthropogenically polluted. Results of practical examples as well as theoretical considerations indicate the importance of the different distribution coefficients in the solvent/water extraction system. The degree of extraction can be considerably increased by the application of suitable mixtures of solvents. In waters with a known composition, the probably detectable EOX-quantity can be calculated by means of theoretical degrees of extraction. 相似文献
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The patterns of variation of TiO2 conent during magmatic evolution are different in the so called “orogenic” and “anorogenie” basic associations; these last terms, which are the cause of much misunderstanding, can be replaced by the terms “isotitaniferous” and “anisotitaniferous”. 相似文献
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D. Offermann M. Jarisch H. Schmidt J. Oberheide K.U. Grossmann O. Gusev J.M. Russell III M.G. Mlynczak 《Journal of Atmospheric and Solar》2007,69(17-18):2139
The “wave turbopause” is defined as the mesospheric altitude level where the temperature fluctuation field indicates a substantial increase in wave amplitudes in the vertical direction.The turbopause altitude is analyzed on the basis of four years of SABER data (2002–2005, Version 1.06). Substantial seasonal and latitudinal variations are found, with some interannual variability also present. Seasonal changes are annual at high latitudes, semi-annual at low latitudes, and a mixture of both at middle latitudes. Southern hemisphere data are similar as in the North if shifted by half a year. Latitudinal variations show a minimum in the tropics and two relative maxima at middle latitudes.The “wave turbopause” is found near to zero-wind lines or low-wind zones (zonal wind). It is compared to rocket and other measurements, and interesting similarities are obtained. The wave turbopause can also be found in the HAMMONIA GCM. A preliminary analysis shows results similar to those of the SABER measurements. 相似文献