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971.
We describe newly developed numerical procedures used to analyze and process sea-echo data acquired with National Oceanic and Atmospheric Administration's (NOAA) dual-site HF-radar system called Coastal Ocean Dynamics Applications Radar (CODAR). CODAR is a transportable shore-based system that can map surface currents out to a nominal range of 50 km. Since its introduction in 1976, it has performed well in a dozen major experiments. Until recently, however, the data processing was labor intensive, difficult to understand, and slow. The processing presented here largely corrects these difficulties, giving CODAR reliable real-time mapping capabilities. 相似文献
972.
The aqueous photochemical transformation of acrylic acid 总被引：3，自引：0，他引：3
Acrylic acid in sea water is thought to occur mostly as the product of microbial cleavage of dimethylsulphoniopropionate (DMSP), but could also be a pollutant introduced by waste waters of the organic chemical industry. Solutions of acrylic acid in natural and artificial sea water, and distilled and riverine water were photolyzed using a photochemical reactor and exposure to sunlight. The transformation of acrylic acid comprises the decarboxylation of the carboxylic group and subsequent polymerization to a polyethylene type molecule. Kinetic studies showed the lowest reaction rate in distilled water and somewhat higher and very similar rates in other aqueous media. The approximately similar reaction rates in all natural waters studied suggest that inorganic ions, especially Na+, Mg2+ and halides, and dissolved organic matter (probably humics) enhance the reaction rates. On studying the influence of different concentration ranges on the reaction kinetics, an exponential increase of rates with decreasing concentration was found. The reaction rate in the sea water solution in field conditions is rather slow. In thirty days exposure about 15% of the reactant was transformed. This reaction seems to be important in the marine environment in specific conditions, especially in phycospheres and macroaggregates where higher concentrations of acrylic acid inhibit the bacterial metabolism. 相似文献
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Sea surface temperature and zooplankton, North Sea, 1948 to 1983 总被引：2，自引：0，他引：2
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