Page 35 - Subyek Encyclopedia - Encyclopedia of Separation Science
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30 I / CENTRIFUGATION/ Derivatization
Figure 7 Particle separation in swinging-bucket, fixed-angle and vertical-tube rotors. Dark shading represents pelleted material, light
shading in floating components, and band are indicated by black lines. (Courtesy of Beckman Instruments, Inc.)
capacity may be insufRcient for certain applica- as minimal wall effects, maximum particle and
tions. This obstacle may be addressed with zonal gradient resolution during sedimentation and recov-
rotors, which provide a larger internal volume for ery, rapid gradient formation, and high rotation
a given radius. Zonal rotors are bowls or cylindrical speeds. Due to their higher efRciency and capa-
cavities equipped with a central core and attached city, zonal rotors are widely utilized in applications
vanes or septa that divide the rotor into four or more ranging from separation/puriRcation of proteins, vi-
sector-shaped compartments. Zonal rotors present ruses and subcellular components to the concentra-
additional advantages over bottle centrifuges such tion of coal or kerogen macerals. Zonal centrifuges
