Fractionators Lieberman

Lieberman gives two rules of thumb for troubleshooting fractionators that could also be used as checks on a design. First, the pressure drops across a section of trays must not exceed 22% of the space between the tray decks, to avoid incipient flood. Mathematical , hold... 

Packed columns are gaining ground on trayed columns. Lieberman states that based on his design and operating experience, a properly designed packed tower can have 20-40% more capacity than a trayed tower with an equal number of fractionation stages. 

In the framework of the Langmuir adsorption-desorption model, all O atoms approaching the fraction 1 - 0 of the caibon surface not covered by C 0 complexes immediately react, forming the complexes. The kinetic equation for the fraction 6 can be written as (Lieberman Lichtenberg, 1994)... 

Amorphous silicon deposition rates from silane in the PECVD process are typically in the range 5-50 nm/min. To analyze the kinetics of the deposition process (McCaughey Kushner, 1989 Lieberman Lichtenberg, 1994), consider a simple surface model illustrated in Fig. 8-28. The surface of amorphous silicon consists of a combination of active (a) and passive (p) sites in the framework of the simplified model. The active sites contain at least one open free bond the fraction of the surface covered by active sites is 0. In the passive sites, all bonds are occupied by silicon or hydrogen atoms (see Fig. 8-28) the fraction of the surface covered by passive sites is 0p (0a + = ) Creation of new active sites is due... 

This reaction is the first committed step in the conversion of IMP to AMP and represents a branch point in the synthesis of IMP, the end product of tie novo purine biosynthesis. Although it had been known for some time that nitrogen from dietary components is rapidly incorporated into cellular AMP, especially into the 6-amino group 1, 2), specific s3mthesis of AMP from IMP was not demonstrated until 1955. Abrams and Bentley (3) showed that the conversion occurred in rabbit bone marrow while Lieberman (4) demonstrated it in Escherichia coli. Carter and Cohen (5, 6) isolated and characterized adenylosuccinate from yeast extracts. Lieberman (4) demonstrated that adenylosuccinate could be formed reversibly from IMP and aspartate by a partially purified enzyme fraction fromE. coli. 

Lieberman R, Padeletti L, Schreuder J, et al. Ventricular pacing lead location alters systemic hemodynamics and left ventricular function in patients with and without reduced ejection fraction. J Am CoU Cardiol 2006 48 1634-41. 

From N. P. Lieberman, "Packing Expands Low-Pressure Fractionators," Hydrocarbon Processing. April 1984. 

Lieberman, I had a check sample run on our naphtha product. We now have 21 percent jet fuel in the naphtha, not 10 percent. You ve made fractionation worse, not better."... 

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