Centrifugation techniques

In a centrifuge technique, various centrifuge types are used for sludge thickening. 

Glassification. Classification (2,12,26,28) or elutriation processes separate particles by the differences in how they settle in a Hquid or moving gas stream. Classification can be used to eliminate fine or coarse particles, or to produce a narrow particle size distribution powder. Classification by sedimentation iavolves particle settling in a Hquid for a predetermined time to achieve the desired particle size and size distribution or cut. Below - 10 fim, where interparticle forces can be significant, gravitational-induced separation becomes inefficient, and cyclone and centrifugation techniques must be used. Classification also separates particles by density and shape. Raw material separation by differential sedimentation is commonly used in mineral processiag. 

Massecuite i.s used to form and then remove sugar crystals from molasses by a centrifugal technique. 

Destruction Liquid Centrifugal techniques Coalescence Destruction Gravity settlement Total enclosure Wet scrubbing... 

Figure 4. Binding was measured in rat brain synaptosomes using a rapid centrifugation technique. Total ( ), and nonspecific ( ) binding of tritiated PbTx-3 were measured, their difference representing specific binding (A). Rosenthal analysis yields a of 2.6 nM and a B of 6.0 pmol toxin bound/mg protein.

Gollany HT, Bloom PR, Schumacher TE. Rhizosphere soil-water collection by immiscible displacement-centrifugation technique. Plant Soil 1997 188 59-64. 

A centrifugation technique used to determine the oligomeric or monomeric status of an enzyme during catalysis. For example, this method can address such questions as Is the catalytically active form of the enzyme a dimer or monomer Is there cooperativity in the interconversion between the forms ... 

The reacting enzyme centrifugation technique has been used with yeast hexokinase and with phosphoenolpy-ruvate carboxykinase. ... 

Fuel. The nuclear fuel cycle starts with mining of the uranium ore, chemical leaching to extract the uranium, and solvent extraction with tributyl phosphate to produce eventually pure uranium oxide. If enriched uranium is required, the uranium is converted to the gaseous uranitim hexafluoride for enrichment by gaseous diffusion or gas centrifuge techniques, after which it is reconverted to uranium oxide. Since the CANDU system uses natural uranium, I will say no more about uranium enrichment although, as I m sure you appreciate, it is a major chemical industry in its own right. 

Based on the differences between the solid and liquid density, batch centrifugation techniques are often used in the discovery phase as a convenient tool to separate the cell from the medium. Highspeed ultracentrifugation instruments have... 

In the previous section it is seen how a separation of two substances A and B may be effected by the establishment of a steady state in a system in which thermal and ordinary diffusion oppose one another. In this section we describe the analogous situation which is obtained when ordinary and pressure diffusion are in competition with each other. Use is made of this result in the separation of organic liquids or isotopes by centrifuging techniques. 

For studies of membrane composition, the first task is to isolate a selected membrane. When eukaryotic cells are subjected to mechanical shear, their plasma membranes are torn and fragmented, releasing cytoplasmic components and membrane-bounded organelles such as mitochondria, chloroplasts, lysosomes, and nuclei. Plasma membrane fragments and intact organelles can be isolated by centrifugal techniques described in Chapter 1 (see Fig. 1-8). 

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