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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Measurement of the apparent dissociation constants of carbonic acid in seawater at atmospheric pressure

Mehrbach, Carl 09 March 1973 (has links)
The apparent dissociation constants of carbonic acid were determined as functions of temperature and salinity in seawater at atmospheric pressure. There is fair agreement between my values of K'₁ and those of Buch et al. (1932), Lyman (1956), and Hansson (1971). My values, on the average, are 6.7% lower than Buch et al.'s (1932), 4.6% smaller than Lyman's (1956), and 4.0% higher than Hansson's (1972). My values for K'₂ are smaller than those reported by other workers. They differ by 3.4% from Hansson's (1972) values, and 26% from Buch's (1938). Lyman's (1956) values are larger than mine by 3.2% at temperatures of 25°C and below, and greater by 13.4% at 35°C. / Graduation date: 1973
2

Bicarbonate and carbonate ion association with sodium, magnesium and calcium at 25°C and 0.72 ionic strength

Hawley, John Edward 29 March 1973 (has links)
Graduation date: 1973
3

Recycling of iron and conditioning of sea water by a marine dinoflagellate

Frey, Bruce E. 07 March 1974 (has links)
Graduation date: 1974
4

Ion association and activity coefficients in electrolyte solutions

Johnson, Kenneth Stewart 13 March 1979 (has links)
Graduation date: 1979 / Best scan available for p.316-317, 319-320.
5

The solubility of CaCO₃ in seawater and in electrolyte solutions

Plath, David Carl 23 April 1979 (has links)
Graduation date: 1979
6

The direct examination of biologically active Cu in seawater

Zorkin, N. R. January 1983 (has links)
An analytical technique for the differentiation of biologically active copper (Cu) in seawater was developed. The procedure involves passing a seawater sample through an ion exchange resin of the sulponate type until complete breakthrough of metal ion is achieved. The sorbed Cu is then eluted and its total concentration is determined by anodic stripping voltammetry. Comparison with Cu adsorption from standard seawater samples of similar composition, pH, and ionic strength yields a Cu equivalent measurement that is related to the free cupric ion activity of the sample. Since the cupric ion is believed to be the toxic form of the metal, the Cu equivalent measurement can be related to the biologically active fraction of Cu. The measurement of biologically active Cu by the resin technique was verified by comparing the analytical results with results from phytoplankton bioassays. Tests were first conducted in artificial seawater that had its chemistry well defined and where model organic ligand (EDTA, NTA, histidine and glutamic acid) were used to control the speciation of the metal. In the experiments using the organic ligands EDTA, NTA, or glutamic acid added to Cu spiked artificial seawater, a strong relationship between the Cu equivalent values and growth rates of the bioassay organism was found (r=0.92). However, in experiments with histidine, this relationship was much weaker and was attributed to the adsorption of positively charged Cu-histidine complexes onto the resin. The adsorption of these complexes results in overestimating the amount of biologically active Cu present in the sample. The few studies on the electrochemical nature of organic complexing agents in seawater suggests, however, that most are negatively charged. Thus the technique would be suitable in many seawater systems. The analytical and bioassay techniques were then applied to natural seawater samples collected from five depths in a local fjord. A discrepancy was found between some of the bioassay and resin test results. However, the discrepancy was attributed to a physiological Cu-Mn interaction in the bioassay organism and not to a problem with the resin technique. / Science, Faculty of / Earth, Ocean and Atmospheric Sciences, Department of / Graduate
7

Studies of trace metals in shelf waters of the British Isles

Tappin, Alan David January 1988 (has links)
No description available.
8

Surface eddy mixing in the global subtropics

Busecke, Julius JM January 2017 (has links)
The salinity of the ocean is inherently linked to the global hydrological cycle by net evaporation. The surface salinity, however does not just act like a 'rain gauge', ocean dynamics are vital in shaping the sea surface salinity (SSS) distribution. Here I investigate the effect of unsteady motions on scales of several hundred km and smaller - mesoscale eddies - on the water masses in the saltiest regions of the surface oceans. These water masses are eventually subducted equatorward and contribute to the shallow overturning circulation by transporting surface signals from the subtropics to the tropics, making them important components of the variable climate system. Towed CTD measurements in March/April 2013 (a component of the NASA SPURS process study) within the North Atlantic SSS maximum (SSS-max) reveal several relatively fresh and warm anomalies, which deviate strongly from climatological conditions. These features introduce a large amount of freshwater into the subtropical region, exceeding the amount introduced by local rain events. The scales and evolution of the features strongly suggest a connection to mesoscale dynamics. This is supported by high-resolution regional model output, which produces an abundance of features that are similar in scale and structure to those observed, confirming the importance of eddy mixing for the near surface salinity budget of the North Atlantic SSS-max. Observations from the Aquarius satellite and the Argo array in the global SSS-max revealed marked differences in the mean shape and variability of the SSS-maxima. These results motivated an investigation of the role of eddy mixing in setting the regional characteristics of SSS maxima. Observed surface velocities from altimetry are used to stir salinity fields in high-resolution idealized model experiments. Using a water mass framework (salinity coordinates) temporal variability in eddy mixing can be quantified, using diagnostics for the total diffusive flux into the SSS-maxima (transformation rate; TFR) as well as the estimated cross-contour diffusivity(effective diffusivity,$K_{eff}$). Both diagnostics reveal distinct variability in the different ocean basins. In the North Atlantic, both $TFR$ and $K_{eff}$ are dominated by changes in the velocity field while the North Pacific shows high sensitivity of the temporal variability in eddy mixing with respect to the initial conditions used, which represent seasonal/interannual change of the SSS-max shape and position. This implies that temporal variability of eddy mixing and diffusivities must be taken into account when constructing salinity budgets in these regions. Furthermore, the translation of results from one SSS-max region to the other might not be possible, particularly when considering a changing climate, which might influence the mechanisms responsible for temporal variability differently. Lastly evidence is presented for large scale diffusivity variability (particularly in the Pacific), connected to large scale climate fluctuations (ENSO). The evidence presented here suggests a significant modulation of surface diffusivities by climate variability, which represents a feedback mechanism not commonly recognized nor included in modern climate simulations.
9

The determination and distribution of cobalt and nickel in tropical Pacific water / Cobalt and nickel in tropical Pacific water

Forster, William Owen January 1966 (has links)
Typescript. / Thesis (Ph. D.)--University of Hawaii, 1966. / Bibliography: leaves [122]-127. / ix, 127 l illus., tables (1 fold)
10

The characterization of humic substances in seawater

Stuermer, Daniel Harryson January 1975 (has links)
Thesis. 1975. Ph.D.--Massachusetts Institute of Technology. Dept. of Earth and Planetary Sciences. / Vita. / Bibliography: leaves 169-187. / by Daniel H. Stuermer. / Ph.D.

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