Polynuclear aromatic hydrocarbons parameter

Study of the polynuclear aromatic hydrocarbons offers a point for the merger of the fully empirical pa relationship with the more theoretical molecular orbital treatment. A detailed review of recent progress in this area is presented by Streitwieser (1961). The success of the simplest molecular orbital treatment is illustrated in Fig. 35. This figure presents a correlation of the relative rates of nitration (Table 6) for a series of alternant polynuclear hydrocarbons. The correlation parameters are the localization energies, NT, devised by Dewar (1952). A more sophisticated procedure, the molecular orbital w-technique, which permits the... 

Parameters for the Substitution Reactions of the Polynuclear Aromatic Hydrocarbons... 

Chemielowiec, J. Sawatzky, H. Entropy dominated high performance liquid chromatographic separations of polynuclear aromatic hydrocarbons. Temperature as a separation parameter. J. Chromatogr. Sci. 1979, 17, 245. 

A major step in the miniaturization of HPLC columns was done early in 1967 by Horvath and co-workers [1,2], when investigating the parameters that influence the separation of nucleotides in a 1-mm-i.d. column. These columns were then named microbore columns. A further step in the miniaturization process was done in 1973, by Ishii and co-workers, by separating polynuclear aromatic hydrocarbons (PAHs) in a... 

Animal studies with structurally related polynuclear aromatic hydrocarbons (PAHs), such as benzo(d )py-rene, benz(it)anthracene, and 3-MC, confirmed that intestinal transport readily occurs primarily by passive diffusion after oral dosing. From the partitioning parameters, the rate-limiting step involves solvation of transfer species in the interfacial water at the phospholipid surface. 

S, Reindl, F. Hofler, Optimization of the parameter in supercritical fluid extraction of polynuclear aromatic hydrocarbons from soil samples. Anal. Chem., 66 (1994), 1808-1816. 

As polynuclear aromatic hydrocarbons show a high tendency towards undesired gas-phase nucleation and soot formation, they should be avoided by choosing a suitable critical residence time and other appropriate processing parameters. 

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