Homogenization ball mill

After the molten glass has become a homogeneous Hquid, it is poured in a thin stream into water or between closely spaced, water-cooled rotating metal rollers. This quenched glass, termed frit, is a friable material easily reduced to small-sized particles by a ball-milling operation. Ball-milling the glass frit into small-sized particles can be carried out whether the frit is to be used wet or dry (see Size reduction). 

Fish tissue is homogenized with a Polytron apparatus using methanol as a solvent, or extracted in a ball mill with hexane. The extracts are evaporated to dryness, dissolved in ethyl acetate toluene, and cleaned up on a gel permeation column followed by an alumina column. Analysis is performed by GC/NPD (Muir et al. 1981). Recovery is acceptable (79-97%) and limit of detection is 10 ng/g (Muir et al. 1981). 

The pigments are incorporated into the resins before crosslinking to ensure homogeneous coloration. This can be done in the molten resin, for example in a kneader at about 90°C, or in dissolved or liquid resins by the liquid resin method. Ball mills are normally used for coloring prewetted powder molding compounds that have not yet been cured. 

A range of reactions have been reported which take place between two solids under the influence of mechanical agitation such as ball milling. A reasonably large range of reachon types has been reported [59]. Concerns over homogeneity and reproducibility at scale plus process safety aspects of the control of exothermic reachons may mean that this technology could only be of interest in a very limited number of cases. 

Radionuclide Analyses of Human Liver. Several specimens (12) of human liver obtained at autopsy were prepared similarly, except that after they were freeze-dried they were ball-milled to insure homogeneity of radionuclide distribution in the counting sample. The powdered samples were then compressed into aluminum cans and counted for approximately 2000 minutes. 

The powdered aminoplast is supplied from ball mill (1) to buffer tank (2) with an agitator and then to feed hopper (3) of mixer (4) wherein it is processed until a homogeneous plastic extrudate is obtained. 

Ball mills are best suited for breaking up strong cell walls such as those encountered in Gram-positive bacteria, but scale-up is limited beyond the small pilot scale. French presses are the apparatus of choice for large-scale homogenization of cells. 

In industrial and laboratory settings the subdivision process more commonly involves the comminution of large particles or aggregates into smaller sizes, either dry with subsequent dispersion (size reduction to the order of a few pm) or directly in a slurry (size reduction to as small as a few tenths of pm). Examples of comminution machines include agitator ball mills, colloid mills, cutting mills, disk mills, homogenizers, jet mills, mechanical impact mills, ring-roller mills, and roll crushers. 

In the wet process, the solid material, after dry crushing, is reduced to a fine state of division in wet tube or ball mills and passes as a slurry through bowl classifiers or screens. The slurry is pumped to correcting tanks, where rotating arms make the mixture homogeneous and allow the final adjustment in composition to be made. 

Sufficient heat transfer is achieved through good sample contact with the heating element of the pyrolyzer. Thus, a lignin is preferably dissolved and applied directly to the surface of the heating element. When the sample is insoluble, its shape and particle size become important parameters. To obtain reproducible results, wood samples should be homogenized in a vibratory ball mill and subsequently dried completely. 

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