Fine particulate material

In other parts of the world, plywood adhesive fillers are obtained from local sources and may be quite different than those used in North America. In Southeast Asia, banana flour is quite important. In Europe, calcium carbonate (chalk) is often used. Nearly any fibrous material or fine particulate material capable of forming a functionally stable suspension can be made to work if the formulator is sufficiently skillful. However, the mix formulator will be very specific about the type and grade of filler to be used in a particular mix. Substitutions may lead to serious gluing problems. 

Anderberg, E.K., and Nystrom, C. (1990), Physicochemical Aspects of Drug Release X. Investigation of the Applicability of the Cube Root Law for Characterization of the Dissolution Rate of Fine Particulate Materials, Intemat. J. of Pharma., 62, 143-151. 

BS 3406, (1963) reconfirmed (1983), British Standard Methods for Determining Particle Size Distribution, Part 3 Air Elutriation Methods, 266 Stein, F. and Com, M. (1976), Powder TechnoL, 13, 133-141,266 Crandall, W.A. (1964), Development of standards for determining the properties of fine particulate material. Winter Annual Meeting ASME,... 

The deliberate manipulation of particle size leads to a measure of control of activity and side-effects. Rapid solution of nitrofurantoin from tablets of fine particulate material led to a high incidence of nausea in patients, as local high concentrations of the dmg produce a centrally mediated nausea. Development of macrocrystalline nitrofurantoin (as in Macrodantin) has led to the introduction of a form of therapy in which the incidence of nausea is reduced. Capsules are used to avoid compression of the... 

MIPs are generally produced as opaque, vitreous, brittle, plastics. To be of practical use MIPs need to be reduced to a fine particulate material of uniform particle size. Typically, this is achieved by grinding processes, either by hand in a mortar and pestle or by mechanical means. The material is then sieved to give a powder of fixed upper particle size ( 25-45/im). Depending upon the final application, this material is then sedimented over a pre-determined time period to remove material that is too fine. The sedimentation step is particularly important if the MIP is to be used for HPLC applications where fine material causes high back-pressure and column blockage. 

The procedure of sorbent removal (especially silica and alumina) from plate backings should always be performed in a fume cupboard, and a dust mask should be worn to avoid breathing dangerous fine particulate material coated in substances of (presumably) unknown composition. 

The immediate physical effects of moisture are most pronounced with fine particulate materials, because these are more variable in density condition and offer wider shear strength changes than coarse particulates. At low... 

Figure 23.3 shows a general scheme of the processes of biomass conversion. It should be noted that the feed and separation processes are very specific and important for separating the gases from very fine particulate materials, as well as the liquid. However, they will not be described here. The study of the reactors will be discussed later. 

A slurry is a mixture of a liquid and solid particles. The term sludge typically refers to a highly concentrated slurry containing fine particulate material. Each year, vast tonnages of slurries are pumped. Slurries are often used to transport coal, phosphates and minerals. Dredging of sand and silt in the maintenance of waterways is another example of sohds handled in slurry form. In most slurries, the liquid phase is water. However, coal-oil and coal-methanol fuels are examples of slurries made up with liquids other than water. 

Although they cannot reject any dissolved salts or other low-molecular-weight soluble matter, UF systems can remove very fine particulate material and high-molecular-weight organic matter from water streams. To remove any low-molecular-weight soluble species with a UF membrane, a process must occur to convert the soluble matter to particulate form. As examples, soluble phosphorus may be precipitated with a metal salt, soluble organics may be adsorbed onto powdered activated carbon, and soluble iron may be oxidized to particulate form. All of these processes and others will allow a UF membrane to remove even soluble matter. 

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