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981.
Demidov A. B. Gagarin V. I. Eremeeva E. V. Artemiev V. A. Polukhin A. A. Shchuka S. A. Grigoriev A. V. Khrapko A. N. Flint M. V. 《Oceanology》2021,61(5):645-661
Oceanology - Spatial and vertical variability of primary production (PP) and Chl a were studied in the framework of the 76th cruise of R/V Akademik Mstislav Keldysh to the Kara Sea from July 7 to... 相似文献
982.
Zhmur V. V. Novoselova E. V. Belonenko T. V. 《Izvestiya Atmospheric and Oceanic Physics》2021,57(6):632-641
Izvestiya, Atmospheric and Oceanic Physics - The potential vorticity (PV) in the ocean is considered, including the history of the term. Various aspects and basic formulas used to calculate the PV... 相似文献
983.
In turbidites, homogeneous and pelagic deposits of the Zaire Fan Th, La, Sm, and Rb and to a lesser extent Yb and Ta correlate strongly. La, Sm, Yb, Rb, Ta, and Th increase two-fold in Te3 turbidite intervals relative to Te 1 due to an increase in clay fraction with which these elements occur associated preferentially.Hf and Zr are anomalously high in Tel and Tel intervals which is probably a result of mineral separation. Zr is absent in Te3 intervals and the homogenous and pelagic deposits. Ba, Br. and U are lowest in turbidites and highest in homogenous continental slope deposits which is probably caused by upwelling. Cc anomalies may be related to the crystallinity of smectite. 相似文献
984.
985.
Single-channel seismic reflection profiles show evidence for areas of significant gas accumulation at the head of the Cape Fear Slide on the continental rise off North Carolina. Gas accumulation appears to occur beneath a gas hydrate seal in landward-dipping strata and in domed strata associated with diapirism. In addition, gas venting may have occurred near diapirs located at the head of the slide. 相似文献
986.
G. Pagano M. Cipollaro G. Corsale A. Esposito E. Ragucci G.G. Giordano N.M. Trieff 《Marine environmental research》1985,17(2-4)
The aim of this study was to compare the biological actions of selected chlorinated biphenyls (CB's) (with different degrees of chlorine substitution), using the sea urchin test system, for their ability to affect fertilisation, embryogenesis and mitotic activity. Sea urchin embryos were exposed to the test agents throughout larval development or for shorter intervals (e.g. before or after hatching). Sperm or eggs were exposed before fertilisation, thereafter the contaminants were removed from embryo cultures. The results showed maximal activities from medium-chlorinated (tetra- and hexachloro-substituted) compounds, as compared to low- and high-chlorinated biphenyls (mono-, di- and octachloro-substituted), at nominal levels ranging from 10−6m to 10−5m. This held true for the different parameters and treatment schedules. Developmental defects were only detected following post hatching exposure of embryos to CB's, whereas pre-hatching exposure failed to reveal any embryological or cytogenetic abnormalities. 相似文献
987.
988.
Submarine groundwater discharge (SGD) into a coastal lagoon off Perth, Western Australia, contains nitrate and silicate in concentrations two orders of magnitude higher than those of the receiving waters. This discharge delivers enough nitrate to replace that dissolved in the lagoon water mass about every eight days and enough silicate to replace the lagoon silicate in about 48 days. The delivery rate of nitrate nitrogen by SGD is equal to about 48% of that required for observed growth rates of lagoon macrophytes. Surface salinity is lower close to the shore as a result of SGD. During calm conditions a salinity front was observed in the lagoon, with a nearshore pool of nutrient-enriched water floating above the more saline ocean water. 相似文献
989.
990.
Rabindra N Roy Lakshimi N Roy Kathleen M Vogel C Porter-Moore Tara Pearson Catherine E Good Frank J Millero Douglas M Campbell 《Marine Chemistry》1993,44(2-4)
The pK1* and pK2* for the dissociation of carbonic acid in seawater have been determined from 0 to 45°C and S = 5 to 45. The values of pK1* have been determined from emf measurements for the cell: where X is the mole fraction of CO2 in the gas. The values of pK2* have been determined from emf measurements on the cell: The results have been fitted to the equations: where T is the temperature in K, S is the salinity, and the standard deviations of the fits are σ = 0.0048 in lnK1* and σ = 0.0070 in lnK2*.Our new results are in good agreement at S = 35 (±0.002 in pK1*and ±0.005 in pK2*) from 0 to 45°C with the earlier results of Goyet and Poisson (1989). Since our measurements are more precise than the earlier measurements due to the use of the Pt, H2|AgCl, Ag electrode system, we feel that our equations should be used to calculate the components of the carbonate system in seawater. 相似文献
Pt](1 − X)H2 + XCO2|NaHCO3, CO2 in synthetic seawater|AgC1; Ag
Pt, H2(g, 1 atm)|Na2CO3, NaHCO3 in synthethic seawater|AgC1; Ag
lnK*1 = 2.83655 − 2307.1266/T − 1.5529413 lnT + (−0.20760841 − 4.0484/T)S0.5 + 0.08468345S − 0.00654208S1
InK*2 = −9.226508 − 3351.6106/T− 0.2005743 lnT + (−0.106901773 − 23.9722/T)S0.5 + 0.1130822S − 0.00846934S1.5