Nitrogen fractions, transfer

At high temperature, sodium and its fused haHdes are mutually soluble (14). The consolute temperatures and corresponding Na mol fractions are given in Table 3. Nitrogen is soluble in Hquid sodium to a limited extent, but sodium has been reported as a nitrogen-transfer medium in fast-breeder reactors (5) (see Nuclearreactors). 

In principle, the catalytic converter is a fixed-bed reactor operating at 500—620°C to which is fed 200—3500 Hters per minute of auto engine exhaust containing relatively low concentrations of hydrocarbons, carbon monoxide, and nitrogen oxides that must be reduced significantly. Because the auto emission catalyst must operate in an environment with profound diffusion or mass-transfer limitations (51), it is apparent that only a small fraction of the catalyst s surface area can be used and that a system with the highest possible surface area is required. 

The trimer samples and low MW fractions were dissolved and analyzed in THF solution. Solutions were prepared in an inert atmosphere and kept under a blanket of nitrogen except for short Intervals during which transfer or injection operations were conducted as required for certain analyses. 

Pass the solution derived from Section 6.2.2 through a Cig cartridge (conditioned prior to use successively with 5mL of acetonitrile and 10 mL of water), then elute interfering substances with 15 mL of acetonitrile-water (3 17, v/v) and discard the eluate. Elute imibenconazole-debenzyl with 20 mL of acetonitrile-water (2 3, v/v) and collect the eluate in a 100-mL separatory funnel (imibenconazole-debenzyl fraction). Elute imibenconazole with 20 mL of acetonitrile-water (17 3, v/v) and collect the eluate in a 100-mL separatory funnel (imibenconazole fraction). Add 30 mL of 20% sodium chloride aqueous solution and 40 mL of ethyl acetate to each separatory funnel and shake the funnel with a mechanical shaker for 5 min. Collect the ethyl acetate extract, dry the extract with anhydrous sodium sulfate and transfer into a 100-mL round-bottom flask. Concentrate the ethyl acetate extract to near dryness by rotary evaporation and dry with a stream of nitrogen. Dissolve the residue of each fraction in acetone for gas chromatographic determination as in Section 6.3. 

The difference in mole fractions is most significant in the case of S02 where this difference is 15% of the bulk phase level. This result indicates that external mass transfer limitations are indeed significant, and that this difference should be taken into account in the analysis of kinetic data from this system. Note that there is a difference in nitrogen concentration between the bulk fluid and the external surface because there is a change in the number of moles on reaction, and there is a net molar flux toward... 

The input requirements for post-flashover types of models can be quite broad. Besides the compartment and vent dimensions, detailed fuel combustion characteristics are often needed. The fuel characteristics include the fraction of carbon, hydrogen, nitrogen, and oxygen that make up the fuel, the burning efficiency, and the quantity of fuel available for burning. Mechanical ventilation flow rates and the material properties of the compartment boundaries may be necessary. Some models can account for the heat transfer through the boundaries in detail, and may even allow the user to supply time-dependent material properties. An example of a post-flashover fire model is COMPF (Babrauskas, 1979). 

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