Koch system

Astrologers have long debated the best way of slicing up a chart. The most common approaches are the Koch system, a time-based method introduced in 1962, and the Placidus system, an equally complex technique named after Placidus de Tito, a 17th-century astrologer who got it from an Arabian astrologer of the 8th century. Placidus is difficult to calculate and grossly inaccurate in northern latitudes. Nonetheless, because it s widespread, it s the system I use for the charts in this book. 

Olefins are carbonylated in concentrated sulfuric acid at moderate temperatures (0—40°C) and low pressures with formic acid, which serves as the source of carbon monoxide (Koch-Haaf reaction) (187). Liquid hydrogen fluoride, preferably in the presence of boron trifluoride, is an equally good catalyst and solvent system (see Carboxylic acids). 

Static mixing of gas—Hquid systems can provide good interphase contacting for mass transfer and heat transfer. Specific interfacial area for the SMV (Koch/Sulzer) mixer is related to gas velocity and gas holdup ( ) by the following ... 

William Eykamp, Ph.D., Adjunct Professor of Chemical Engineering, Tufts University Formerly President, Koch Membrane Systems Member, American Institute of Chemical Engineers, American Chemical Society, American Association for the Advancement of Science, North American Membrane Society, European Society of Membrane Science and Technology (Section 22, Alternative Separation Processes)... 

FIG. 14-54 Pressure drop for Flexipac packing, sizes No, 1 and No.. 3, Air-water system at atmospheric pressure. Liquid rate in gallons per minute-square foot. To convert (feet per second) (younds per cubic foot) " to (meters per second) (kilograms per cubic meter) " , multiply by 1,2199 to convert gallons per minute-square foot to pounds per hour-square foot, multiply by 500 to convert inches of water per foot to millimeters of water per meter, multiply by 83,31 and to convert pounds per hour-square foot to kilograms per second-square meter, multiply by 0,001.356, Coutiesy Koch Engineering Co., Wichita, Kansas.)... 

FIG, 22-68 Flow schematic for batch (feed valve closed) or semihatch (feed valve open) operation. (Couttesy Koch Membrane Systems.)... 

FIG, 22-69 Flow schematic for stages-in-series. In operation, the block valves are open. All pump inlets are connected, but in such a way as to prevent feed bypassing a stage. (Coutiesy Koch Membrane Systems. )... 

Figure 9-52. Koch/Sulzer packing. Design mass velocity (ib/hr-ft ) for HETP of 7 in. System cis-trans-decaiin moiecuiar weight = 138. Used by permission of Koch Engineering Co., Inc., Bull. KS-1.

Figure 9-53. Koch/Sulzer packing. Design mass velocities for systems other than cis-trans-decaiin are obtained by dividing the values from Figure 9-52 by the f factor. For the following groups corrections should be applied to the number of carbons in the molecule ...

Some OEMs produce many of the individual components required for their systems totally in-house, although there are also a large number of specialist equipment manufacturers for pressure vessel (PV) housings, high pressure pumps, and the like. World-class membrane manufacturers include Trisep, Koch, Fluid Systems, Hydranautics, Du Pont, Osmonics, and Dow. 

Frederiksson, H., Andersson, R., Koch, K., and Amon, P, Calibration of a size-exclusion chromatography system using fractions with defined amylopectin unit chains, /. Chromatogr. A, 768, 325, 1997. 

Sternberg, U., F.-T. Koch, and M. Mollhoff. 1994. New Approach to the Semiempirical Calculation of Atomic Charges for Polypeptides and Large Molecular Systems. J. Comput. Chem. 15, 524-531. 

Plank C, Oberhauser B, Mechtler K, Koch C, Wagner E (1994) The influence of endosome-disruptive peptides on gene transfer using synthetic virus-like gene transfer systems. J Biol Chem 269 12918-12924... 

Koch Membrane Systems, Wilmington, USA, http //www.kochmembrane.com. 

Korkisch and Koch [106,107] determined low concentrations of uranium in seawater by extraction and ion exchange in a solvent system containing trioctyl phosphine oxide. Uranium is extracted from the sample solution (adjusted to be 1 M in hydrochloric acid and to contain 0.5% of ascorbic acid) with 0.1 M trioctylphos-phine oxide in ethyl ether. The extract is treated with sufficient 2-methoxyethanol and 12 M hydrochloric acid to make the solvent composition 2-methoxyethanol-0.1 M ethereal trioctylphosphine acid-12 M hydrochloric acid (9 10 1) this solution is applied to a column of Dowex 1-X8 resin (Cl" form). Excess of trioctylphosphine oxide is removed by washing the column with the same solvent mixture. Molybdenum is removed by elution with 2-methoxyethanol-30% aqueous hydrogen peroxide-12 M hydrochloric... 

A high-performance liquid chromatographic method for nalidixic acid on a strong anion-exchange resin column has been reported, using a mobile phase of 0.01 M sodium tetraborate at pH 9.2 and 0.003 M sodium sulfate. The relative retention time for nalidixic acid in the system reported by Sondach and Koch was 0.86 with sulfanilic acid as the standard at... 

Koch, A. L. and Wang, C. H. (1982). How close to the theoretical diffusion limit do bacterial uptake systems function Arch. Microbiol., 131, 36-42. 

P.A. Smith, M.T. Sng, B.A. Eckenrode, S.Y. Leow, D. Koch, R.P. Erickson, C.R.J. Lepage and G.L. Hook, Towards smaller and faster gas chromatography-mass spectrometry systems for field chemical detection,... 

Bao H, Koch PL (1999) Oxygen isotope fractionation in ferric oxide-water systems low-temperature synthesis. Geochim Cosmochim Acta 63 599-613... 

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