Oxygen flux data

Figure 13.9 Representative experimental oxygen flux data obtained at 23°C at 10% clay loadings. Reproduced from Ref [7] with permission.

Figure 3.86 Comparison of model and experimental data of the oxygen flux leaving the reactor in a single-channel TAP fixed-bed reactor [126]...

Oxygen transport measurements were conducted at 25°C, 0% and 50% relative humidity RH, 1 atm partial oxygen pressure difference using the commercially manufactured diffusion apparatus OX-TRAN 2/20 (Modem Control Inc.). This apparatus employs a continuous-flow method (ASTM-D 3985-81) to measure oxygen flux, J(t), through polymer films or thin sheets. In order to obtain the diffusion coefficient and to accurately determine the permeability coefficient, the data, flux, J(t), were fitted to the solution of Fick s second law ... 

Permeability, P, and difiusion coefficient, D, were obtained by performing a two-parameter least squares fit of the experimental flux data to equation (2). The solubility, S, was obtained from the relationship P = DS. The methodology of these oxygen barrier measurements, data analysis, and the sources of experimental error were previously described in detail elsewhere (7/). 

Bailey, E. (2005). Measurements of nutrient and oxygen fluxes in estuarine and coastal marine sediments Literature review and data report, Technical Report Series Ref. No. [UMCESJCBL 05-091. University of Maryland Center for Environmental Science, Chesapeake Biological Laboratory, Solomons, MD, 36pp. http //www.gonzo.cbl.umces.edu/N%20Chapter%20Flux.pdf. 

Jahnke (1996) extrapolated available benthic-flux measurements from landers and pore-water determinations into a global map of benthic oxygen flux for sediments deeper than 1,000 m. When compared with global primary production rates and sediment-trap particle fluxes, these data indicate that 1% of the primary production reaches deep-sea sediments and is oxidized there (Table 3). Also —45% of respiration in the ocean below 1,000 m occurs within sediments. 

Fig. 6.24 Model results of Soetaert et al. (1996) for a site in the abyssal Pacific. The curve of mineralization rates (oxygen fluxes) is smoother and shows a slight shift compared to the sedimentary carbon flux caused by the effective reaction kinetics. Squares indicate oxygen fluxes determined on the basis of benthic chamber and box corer data.

Fig. 12.5 Relationship between diffusive oxygen uptake (DOU) and the total oxygen flux (TOU). The compilation of several data sets (Reimers 1987 Reimers et al. 1992 Glud et al. 1994 Hales and Emerson 1997 Weber et al. 2001 Wenzhofer and Glud 2002) shows a significant positive correlation between total respiration rates and the portion of nonmolecular transport processes (cf. Jahnke 2001).

The section inverse approach developed by Wunsch exploits hydrographic data along sets of oceanographic sections, and allows estimation of absolute flow velocities perpendicular to the sections. The method was later extended to include nutrient and oxygen data allowing to estimate nutrient and oxygen fluxes across the sections. 

Fig. 1. Oxygen peak data, (a) peak flux (b) metastable liquid superheat, where curves are based on (1), 0 Bochirol, Bonjour, and Weil [ ], O Weil [ ], X Hasel-den and Peters [ ], + Mikhail, from [ ].

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