Permeability salts deposition

Toxicity. The toxicity of barium compounds depends on solubility (47—49). The free ion is readily absorbed from the lung and gastrointestinal tract. The mammalian intestinal mucosa is highly permeable to Ba " ions and is involved in the rapid flow of soluble barium salts into the blood. Barium is also deposited in the muscles where it remains for the first 30 h and then is slowly removed from the site (50). Very Httle is retained by the fiver, kidneys, or spleen and practically none by the brain, heart, and hair. 

The aspect of hole filling by plasma deposition can be demonstrated by the transport characteristics of LCVD-prepared membranes. First, the porosity as porous media calculated from the gas permeability dependence on the applied pressure can be correlated to the salt rejection of the composite membrane as shown in Figure 34.13. The effective porosity s/, where s is the porosity and q is the tortuosity factor, is measured in dry state and may not directly correlate to the porosity of the membranes in wet state. The effective porosity of LCVD-prepared membranes was measured before the reverse osmosis experiment. The decrease of porosity (as porous media) is clearly reflected in the increase in salt rejection in reverse osmosis. 

We may assume that a certain amount of secondary quartz could be deposited from thermal and formation waters. These processes could take place in permeable layers in which formation waters and deep waters can circulate as well as a result of the lowering of the partial pressure of CO under these conditions. In any case the presence of gypsum, anhydrite and baryte in numerous sections of the rocks studied is evidence of the penetration of mineralized waters derived especially from the salt-bearing sections of the Triassic. We have also tried to find a connection between the permeability of the sandstones and the distance of these horizons from tectonic disturbances. It has been noted that the mean permeability of reservoir rocks in holes situated less than 500 m from fractures or faults differs very little from that in rocks from other holes (Fig. 3.9). 

The use of aqueous chloride electrolysis in comparison with molten salt systems has the disadvantage of producing a powdered lead cathode deposit in comparison with molten lead. The production of chlorine can be common to both systems but can be avoided in the aqueous system if iron leach solutions are used as the electrolyte, or proton permeable membranes are used to allow for a separate anolyte solution composition. No clear preference has emerged to date from the many process options examined. 

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