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M. G. Winter 《Engineering Geology》2001,60(1-4):285-294
Spent oil shale (or blaes) is a potentially valuable engineering material and is present in large quantities in the West Lothian area of Scotland. It can be used successfully as general fill or capping layer. However, due to its high quality it may be more suited to use as selected granular fill or sub-base. In particular, cement stabilisation will reduce frost susceptibility and may be a particularly appropriate outlet for spent oil shale for use as sub-base. However, an increase in control and testing may be required, having an effect on the cost of using such materials. Conditions under which spent oil shale should not be used are also identified. 相似文献
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E. Jacques C. Monaco P. Tapponnier L. Tortorici T. Winter 《Geophysical Journal International》2001,147(3):499-516
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J.C. Duchesne I. Roelandts D. Demaiffe J. Hertogen R. Gijbels J. De Winter 《Earth and Planetary Science Letters》1974,24(2):325-335
Major and trace elements have been determined in monzonoritic rocks (hypersthene-monzodiorite or jotunite) from two intrusions belonging to the South Rogaland anorthositic complex (Norway). The rare-earth abundance pattern reveals no Eu anomaly, or only a very small one. This fact together with field observations suggest that these rocks represent the parental magma of the anorthositic suite. High Ti and P abundances, low Si content, high Fe/Mg and K2O/SiO2 ratios are characteristics of the major element geochemistry. Absolute amounts of some trace elements abundances vary distinctly between the two intrusions. K/Rb ratios as high as 1700 are observed. Partial fusion of upper mantle kaersutite is proposed as a possible mechanism of magma generation. Partition coefficients between plagioclase phenocrysts and liquid are determined. 相似文献
55.
Zur Aquatoxizität ausgewählter Harnstoffherbizide und zu ihrer Kategorisierung als Wasserschadstoffe
Eight urea herbicides, as are used for weed control, are investigated for their effect on the green alga Ankistrodesmus falcatus and the warm-water fish Poecilia reticulata and found to be highly toxic for the test alga or highly to moderately toxic for the fish. If other criteria (acute toxicity to warm-blooded animals, carcinogenicity and biochemical degradability) are taken into account too, the tested herbicides have to be classified as very dangerous water pollutants. Legal sanctions to be applied in cases of exceeded limiting values are discussed. 相似文献
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Jellyfish populations in the southeastern Atlantic off the coast of Namibia have increased subsequent to the decline of small pelagic fisheries at the end of the 1960s, although the environment there has also become warmer and the waters off Walvis Bay have become richer in zooplankton in recent years. Laboratory experiments were conducted with the scyphozoan jellyfish Chrysaora fulgida to investigate the effects of food density (0, 30, 70, 100 or 150 Artemia nauplii 200 ml?1), feeding frequency (once daily or once every third day) and water temperature (12, 16 or 20 °C) on the asexual reproduction, growth and development of polyps. The results of a generalised linear mixed-effects model reveal that all variables impacted asexual reproduction, with greater polyp production attained at higher food concentrations, increased feeding frequencies and increased temperatures. The most common mode of asexual reproduction was by lateral budding. These laboratory results suggest that polyps of C. fulgida may have proliferated off Namibia in recent times, which would contribute to increased numbers of jellyfish there. 相似文献
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D. Baines R. D. Oudmaijer A. Mora C. Eiroa John M. Porter B. Merín B. Montesinos D. de Winter A. Cameron J. K. Davies H. J. Deeg R. Ferlet C. A. Grady A. W. Harris M. G. Hoare K. Horne S. L. Lumsden L. F. Miranda A. Penny A. Quirrenbach 《Monthly notices of the Royal Astronomical Society》2004,353(2):697-704
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