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Ohne Zusammenfassung 相似文献
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The following compounds of milk from Indian-Rhino (Rhinoceros unicorns) were examined: water-, fat-, protein-, potassium-, sodium-, calcium-content. Besides this we analyzed by gas-Liquid chromatography the short-chain and the long-chain fatty-acids. 相似文献
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An infiltration method for measuring the saturated hydraulic conductivity under field conditions A new field method to measure the hydraulic conductivity under field conditions, developed by Reynolds and Elrick (1985), is presented and compared with a laboratory method using 100 cm3 cylinder cores. 相似文献
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Atmospheric deposition of bioelements in agrar-ecosystems 1. Report: Deposition of bioelements by precipitation The bioelement deposition by precipitation was measured in 1977–1981 in Göttingen (Niedersachsen). The bioelement concentrations and the deposited quantities are in good agreement with the results of other authors. The mean pH-values of the collected precipitation water in 1980 and '81 in Göttingen was 4,60. The difference to the pH-values measured by Ulrich et al. (1979) in the Solling is explained by the different geographical locations of the ecosystems in connection with the transport of dust and variations in the composition of the soils of the areas. From the view of plant nutrition and soil acidification the contribution of the deposition by precipitation is insignificant for agriculture. Only about 6% of the typical annual Ca-leaching from loamy soils are caused by the H+ input by precipitation. The rest is caused by other influences, especially the soil respiration. 相似文献
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Maria Berdén Nicholas Clarke Lars -Göran Danielsson Anders Sparén 《Water, air, and soil pollution》1994,72(1-4):213-233
We have compared a new FIA method (M1) for aluminium speciation in natural waters and a manual one based on one of Driscoll's proposals (M2). In synthetic solutions, aluminium's fluoro complexes were measured as ‘labile monomeric AP (Al i ) by M2, but not as ‘quickly reacting Al’ (Al qr ) by M1. Aluminium's complexes with Nordic Reference Humic Acid were measured neither as Al i nor as Al qr , and the same result was obtained for Al's citrato complexes. After excluding aluminium's fluoro complexes from Al i , the results of the two methods agreed well for soil leaching samples and fairly well for natural water samples. Detection limits: 10μg L?1 (ca. 0.4 μM) for both methods. Sample throughputs: M1∶66 injections h?1; M2∶5 samples h?1. Repeatabilities (RSD) on natural water samples: M1∶0.6–5.8% and M2 0.7–4.6%. Sample storage studies on soil solutions (FIA method) indicated that storage effects were ‘sample type specific’. A sample with a low level of Al qr and a high DOC level (P2A) was more sensitive to storage than one with a high [Al] qr and a low [DOC] (P2B*). The decrease in [Al] qr was statistically significant after 10 h (P2A) and 24 h (P2B*), respectively. After 3 days' storage, [Al] qr had decreased by some 40% in P2A, while the decrease in P2B* was less than 10% after 8 days. The results of this part of the study also emphasize the importance of careful method standardization in sample storage studies. 相似文献
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