Uniform impregnation

The catalyst impregnation on the dispersed CNFs must be carefully optimized to obtain a sufficient dispersion of noble metals. Dispersion ofthe CNF in the particular solvent is desirable for uniform impregnation ofthe catalyst. CNFs with very small diameter are very important for effective dispersion. Sophisticated procedures for dispersion must be applied. In the present study, nanodispersion at an impeller agitation of 16 500 rpm was applied to disperse the thin CNFs better. 

Composite propellants are made by uniformly impregnating a finely divided solid oxidizer into a plastic, resinous or elastomeric matrix. The matrix usually... 

The use of semi-stable foams, which have a short half-life (i.e., time for half of the contained liquid to drain from the foam) of the order of a few minutes, has made possible a high speed process for uniformly impregnating fabrics with controlled,... 

Uniform impregnation of ruthenium can be obtained with ruthenium chloride in the presence of citric acid the acid is competitive with the very strongly adsorbed complex ruthenium ion although as we saw earlier citric acid will completely displace the chloroplatinate anion. 

All Pd on activated carbon catalysts contained 5 wt.% palladium and were characterized by a high (but varying) Pd dispersion (no thermal pretreatment, highest dispersion catalyst 3). In addition to their Pd dispersion (average Pd crystallite size) the catalysts differed in the reduction degree of Pd, in their content of water (D for dry catalysts 5 wt.% water W for wet catalysts 50-60 wt.% water) and in the Pd distribution (uniform impregnation, catalysts 3, 5 and 6 or egg-shell catalysts, catalysts 1, 2 and 4). The reduction degree is defined as the amount of Pd compared to the total amount of Pd (Pd and Pd ) in the catalyst. Most of tire palladium on the surface of catalysts 3-5 is Pd only, whereas catalysts 1, 2 and 6 consist of Pd" and mainly Pd" species. 

Extensive catalytic tests on small and large uniformly impregnated pellets and on the eggshell catalysts of this study show that maximum 5+ selectivities are obtained at intermediate levds of transport restrictions (Figure 4). The parameter %, and is proportional to ... 

If such lacquers are sprayed with ordinary atomisers, the lacquer particles may easily coagulate before reaching the layer surface, which is extremely unsatisfactory. A much more uniform impregnation is possible by spraying from spray bottles with propellent gas. 

The polymers are usually processed in a preliminary step in the form of prepreg , that is pre-coated and partially cured (polymerized) on the fiber. This prepreging provides uniform impregnation of the fiber bundle and uniform resin-to-fiber ratio. The following polymers are presently available commercially... 

Reagent 0.2 g dipicrylamine is dissolved in 2 ml of 2 N sodium carbonate and 15 ml water. The solution is filtered if necessary. Strips of filter paper (3x6 cm) are soaked in the solution, the excess liquid drained off, and the paper dried in a blast of heated air. If the paper moistened with the reagent solution is dried in the air, it is not so effective, though uniformly impregnated, as paper that has been spread on glass and then dried in a blast of heated air. This treatment results... 

The extracellular sutetance of bone, dentine and cementum is thoroughly and fairly uniformly impregnated with tiny crystallites of apatite between, on the surface of and within the collagen fibrils, wherever there are small spaces between organic components. The apatite crystals are much smaller than those of enamel (see Chapter 28). 

Sanyo claims that the weight ratio of the PEO precursor to the electrolyte solution is very important to uniform impregnation of the mixture within the coated layer of the electrode active materials and too much precursor causes the increase of viscosity of the mixture and results in poor impregnation. The favorable weight ratio of the precursor to the electrolyte solution is between 1 12 and 1 8 according to Sanyo. 

Silica gel was coated on inert flexible poly(ethyleneterephthalate) to 100 pm thickness. Polyacrylic was used as a binder in these plates. Cellulose plates were coated to a 160 pm thickness without binder on inert flexible ester base. Impregnation with B was accomplished by uniformly spraying a 3% B solution on silica gel or cellulose plates. The plates were air-dried and then heated to 100°C for 20 min. For RP-TLC the dried silica gel, cellulose, or borate plates were uniformly impregnated with silicone oil by allowing a 5% solution... 

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