Beads, suspended

Tang et al. used columns packed with a slurry of beads suspended in supercritical C02. This packed column was filled with a dilute sol solution prepared by hydrolysis and polycondensation of tetramethoxysilane and ethyltri-methoxysilane precursors. The column was dried using supercritical C02 and heated first to 120 °C for 5 h followed by another 5 h at a temperature of 250 °C [108-110]. Column efficiencies of 127,000 and 410,000 plates/m were reported... 

Segregated Flow A real example is bead polymerization of styrene and some other materials. The reactant is in the form of individual small beads suspended in a fluid and retarded from agglomeration by colloids on their surfaces. Accordingly, they go through the reactor as independent bodies and attain conversions under batch conditions with their individual residence times. This is called segregated flow. With a particular RTD, conversion is a maximum with this flow pattern. The mean conversion of all the segregated elements then is given by... 

Figure 5. The evolution of the density gradient as a function of time in TLF cell displayed by the positions of the focused zones of three density marker beads suspended in Percoll diluted with water. (Reproduced with permission from reference 14. Copyright 1994 Springer-Verlag.)...

FIGURE 5-29 Experimentally obtained and theoretically predicted sound velocity vs. solids concentration for 8 pm hollow glass beads suspended in Echogel. 

To verify model predictions of phase-velocity variation over a range of solids concentrations, we conducted laboratory measurements with hollow glass beads suspended in Echogel, a water-based gel that is commonly used as a transducer... 

Figure 33 shows the apparent viscosity variation with shear rate for 44 fim glass beads suspended in a 50% bitumen-in-water emulsion at 25 °C. The viscosity ratio of the dispersed liquid phase (bitumen) to the... 

Anthranilic acid was anchored to the polystyrene beads by stirring the beads with an excess of anthranilic acid in ethyl ether or DMF. For example, to 1.00 gm of chloromethylated beads suspended in 50 ml of ethyl ether was added to 0.5 gm of anthranilic acid. This was stirred for 20 hr, filtered, and washed with 200 ml of absolute ethanol. 

For polystyrene beads suspended in an organic solution such as toluene, the thermal diffusion... 

If respiring biomass particles are relatively large mass transfer resistances from the bulk fermentation broth to the outer surface of the biomass particles may occur. In their paper on physical rate processes in industrial fermentation, Calderbank and Jones (58) have reported on liquid-solid mass transfer coefficients kg with ionic resin beads suspended in a stirred vessel. They recommend the following equation... 

Rgure 1 Archimedean screw effect in a rotating coil. (A) Motion of air bubbles and glass beads suspended in water (B) Motion of droplets of one phase of an equilibrated two-phase solvent system suspended in the other phase (C) Hydrodynamic equilibrium of two immiscible solvent phases in a slowly rotating coil. 

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