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H. Volkert 《Meteorology and Atmospheric Physics》1990,43(1-4):231-234
Summary A model orographiy is constructed for a large portion of the Alpine region with nearly equidistant zonal and meridional resolution (3.3 km). Major valleys and massifs, which tend to be smeared out by averaging a high resolution database, are manually reconstructed. A comparison along a crosssection over the crest line of the Eastern Alps in both physical and Fourier space reveals the characteristics of different model resolutions.With 3 Figures 相似文献
924.
Lars H. Blikra 《Engineering Geology》1990,29(4):365-376
Rapid mass movements are common features of hilly or mountainous terrains, and depending on the type of movements or processes involved these give rise to characteristic deposits. Identification of these deposits in mapping programmes gives a clue as to their mode of origin (rockslide/rockfall, snow avalanche, debris flow, fluidal sediment flow) and this can be used to predict rapid mass movements in the future.
A case story from western Norway is described and the value of mapping such deposits for land-use planning and hazard estimation stressed. 相似文献
925.
H. Klapper 《洁净——土壤、空气、水》1990,18(1):81-92
The most important measure is that the freshwater demand of 0.5 m3 per t beet processing is strictly kept to or fallen below, to which a catalogue of measures with ten points is presented. The wastewaters which cannot be used again have to be stored prior to the final purification in order to compensate for quantities and concentrations, aerated storage ponds being successful for small sugar factories as the purification technology. For this, three cases are described as examples: supplementary equipment of two anaerobic ponds with a rod-roll aeration, by which within two months (May to July) the BOD3 is reduced from 1,200 to 11 mg/l. The aeration of a pond of 12.5 ha (370,000 … 500,000 m3) by means of a centrifugal aerator (45 kW) does not lead to completely aerobic conditions: Accumulation up to 350 t BOD5, 200 t organic acids at a reduction of 100 t sulphate, 45 t of which being converted via sulphides by photoautotrophic sulphur bacteria. This combination of anaerobic and aerobic processes is very economical. At aeration with ca. 1 W/m3 in the third case in summer there are achieved wastewater loads which are of a receiving-water quality. 相似文献
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The vibrational properties of metastable Ca-GeO3 perovskite are investigated as a function of temperature using Raman scattering. Mode-assignments are derived from polarized spectra of optically oriented single crystals. Neither symmetry-breaking structural transformations nor soft-mode behavior is revealed in the Raman spectra between room temperature and 650° C. Only a small decrease in the local static octahedral tilt angles can be inferred from the Raman data over this temperature range. A Landau extrapolation of the lowest frequency Ag modes suggests that these modes become critical near 2000° C, a temperature that is above the extrapolated zero pressure melting point. 相似文献
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