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M. Nuruzzaman A. A. Mamun M. N. B. Salleh 《International Journal of Environmental Science and Technology》2018,15(6):1249-1256
There is lack of information regarding ammonia nitrogen (AN), (i.e. NH3-N) decay rate of river water in tropical regions like Malaysia. AN decay rate is a very important kinetic parameter to estimate NH3-N, nitrate nitrogen (NO3-N) and dissolved oxygen concentrations of river water by using computer models. This study presents determination of ammonia nitrogen decay rate of river water in the tropical environment of Malaysia. A laboratory flume was used to conduct twelve experiments. The flume was used to represent the turbulent condition of a typical river. Ammonia nitrogen decay rate for the tropical environment of Malaysia was observed to be between 0.194 and 0.554 per day. Median value of AN decay rate was 0.26 per day, which is slightly lower than the global median value of 0.295 per day. To check the accuracy of flume experiments, the AN decay rate of Pusu River obtained from the flume experiment was used to calibrate and validate ammonia nitrogen concentration of the river by using water quality analysis and simulation program (WASP). Very good calibration and validation results were achieved, which substantiated the accuracy of the flume experiments. 相似文献
625.
Fokin P. A. Zakrevskaya E. Yu. Sahakyan L. G. Grigoryan T. E. 《Lithology and Mineral Resources》2021,56(5):438-459
Lithology and Mineral Resources - Nummulite facies are known to be a good indicator of Eocene shallow-water paleoenvironments. Nummulitic limestones are widespread in the Lower Eocene of... 相似文献
626.
Lithology and Mineral Resources - Upper Paleozoic sections in Taimyr comprise genetic rock complexes of different zones: deep-water shelf; offshore transition zone; shoals, deltas, and beaches of... 相似文献
627.
Sokolov S. D. Tuchkova M. I. Ledneva G. V. Luchitskaya M. V. Ganelin A. V. Vatrushkina E. V. Moiseev A. V. 《Geotectonics》2021,55(5):697-716
Geotectonics - The South Anyui Fold System was formed at the end of the Early Cretaceous at the site of a closed oceanic basin as a result of the collision of the Chukotka microcontinent with the... 相似文献
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Astronomy Reports - Within the framework of the model of the extragalactic background created earlier by the authors, the factors influencing the statistical properties of the confusion noise have... 相似文献
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Doklady Earth Sciences - The first results of studies of vertical particle fluxes in a hydrothermal sedimentary system of a subpolar area of the Mid-Atlantic Ridge under the influence of... 相似文献
630.
Mathematical Geosciences - Manually interpreting multivariate drill hole data is very time-consuming, and different geologists will produce different results due to the subjective nature of... 相似文献