Porters

Porter and Momoh have suggested an approximate but simple method of calculating the total vapor rate for a sequence of simple columns. Start by rewriting Eq. (5.3) with the reflux ratio R defined as a proportion relative to the minimum reflux ratio iimin (typically R/ min = 1-D- Defining Rp to be the ratio Eq. (5.3) becomes... 

Equation (5.8) tends to predict vapor loads slightly higher than those predicted by the full multicomponent form of the Underwood equation. The important thing, however, is not the absolute value but the relative values of the alternative sequences. Porter and Momoh have demonstrated that the rank order of total vapor load follows the rank order of total cost. 

Porter, K. E., and Momoh, S. O., Finding the Optimum Sequence of Distillation Columns—An Equation to Replace the Rules of Thumb (Heuristics), Chem. Engg. J., 46 97, 1991. 

Karplus M and Porter R N 1970 Atoms and Molecules an Introduction for Students of Physical Chemistry (Reading, MA Addison-Wesley)... 

If all the resonance states which fomi a microcanonical ensemble have random i, and are thus intrinsically unassignable, a situation arises which is caWtA. statistical state-specific behaviour [95]. Since the wavefunction coefficients of the i / are Gaussian random variables when projected onto (]). basis fiinctions for any zero-order representation [96], the distribution of the state-specific rate constants will be as statistical as possible. If these within the energy interval E E+ AE fomi a conthuious distribution, Levine [97] has argued that the probability of a particular k is given by the Porter-Thomas [98] distribution... 

The coimection between the Porter-Thomas P(lc) distribution and RRKM theory is made tln-ough the parameters j -and v. Waite and Miller [99] have studied the relationship between the average of the statistical... 

Porter C E and Thomas R G 1956 Fluctuations of nuclear reaction widths Phys. Rev. 104 483-91... 

An interferometric method was first used by Porter and Topp [1, 92] to perfonn a time-resolved absorption experiment with a -switched ruby laser in the 1960s. The nonlinear crystal in the autocorrelation apparatus shown in figure B2.T2 is replaced by an absorbing sample, and then tlie transmission of the variably delayed pulse of light is measured as a fiinction of the delay This approach is known today as a pump-probe experiment the first pulse to arrive at the sample transfers (pumps) molecules to an excited energy level and the delayed pulse probes the population (and, possibly, the coherence) so prepared as a fiinction of time. 

Porter G 1992 Chemistry in microtime The Chemical Bond Structure and Dynamics ed A Zewail (Boston Academic) pp 113-48... 

Porter G 1995 Flash photolysis into the femtosecond—a race against time Femtosecond Chemistry ed J Manz and L Woste (New York VCH) pp 3-13... 

Porter G and Topp M R 1968 Nanosecond flash photolysis and the absorption spectra of excited singlet states Nature 220 1228-9... 

Porter G 1950 The absorption spectroscopy of substances of short life Discuss. Faraday Soc. 9 60-9... 

Orsay Liquid Crystal Group 1970 Theory of light soattering by nematios Liquid Crystais and Ordered Fiuids voH, ed J F Johnson and R S Porter (New York Plenum)... 

Porter M D, Bright T B, Allara D L and Chidsey C E D 1987 Spontaneously organized moleoular... 

Aives C A, Smith E L and Porter M D 1982 Atomic scaie imaging of aikanethioiate monoiayers at goid surfaces with atomic force microscopy J. Am. Chem. Soc. 114 1222-7... 

Porter M D, Bright T B, Allara D L and Chidsey C E D 1987 Spontaneously organized molecular assemblies. 4. Structural characterization of normal-alkyl thiol monolayers on gold by optical ellipsometry, infrared-spectroscopy, and electrochemistry J. Am. Chem. Soc. 109 3559-68... 

Waiozak M M, Chung C, Stoie S M, Widrig C A and Porter M D 1991 Struoture and interfaoiai properties of spontaneousiy adsorbed normai-aikanethioiate monoiayers on evaporated siiver surfaoes J. Am. Chem. See. 113 2370-8... 

Porter G 1983 Transfer and storage of chemical and radiation potential J. Chem. Soo. Faraday Trans. 2 79 473-82... 

Norrish R G W and Porter G 1949 Chemioal reaotions produoed by very high light intensities Nature 164 658... 

Grant, Balaram Gupta, Alice Ku, Gao Liang, Henry Lin, Christine Lui, Chuck McFarland, Ripu Malhotra, Y. K. Mo, Dick Porter, Surya Prakash (who later in Los Angeles became my close colleague and a wonderful friend, see Chapter 8), George Salem, Jacob Shen, John Staral, Jim Svoboda, Paul Szilagyi, and John Welch. 

M. Karplus, R. N. Porter, Atoms Molecules An Introduction For Students of Physical Chemistry W. A. Benjamine, Menlo Park, (1970). 

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