Apparent residual saturation

Sr = apparent residual saturation of the carrier-reservoir rock to... 

The loss of separate phase hydrocarbons during secondary migration is indicated by the apparent residual saturation of hydrocarbons, which is on average in the order of 1 - 3% of the total available pore space of the carrier rocks through which hydrocarbons have migrated. 

For the measurement of homonuclear NOE it is normal to switch off the decoupler just before measurement, in order to reduce artifacts. Small NOE s on sensitive nuclei such as H are conveniently identified by computer subtraction of the enhanced and unenhanced spectra, i.e., by NOE difference spectroscopy. As this subtraction is rarely perfect, it is wise to check for the presence of an overall peak integral to confirm that an apparent residual resonance is not merely a subtraction artifact. The percentage NOE of a peak is readily calculated by comparison of its area with the (negative) area of the large peak which will always arise from saturation at the position of irradiation. Irradiation sufficient for such spectroscopy can be specific within a typical range of +40 Hz. 

The apparent epitope map based on STDs can exhibit rather significant dependence on which particular protein proton(s) is being saturated. For example, saturation of resolved methyl proton resonances from two separate residues may result in STD spectra with different relative and/or absolute intensities. Similarly, saturation of a specific tyrosine ring proton vs. a specific methyl group can result in different STD spectra. 

Seong (2002) compared silylated (aldehyde) and silanated (amine and epoxy) compounds from several commercial sources to the performance of an antigen (IgG) microarray. In addition, the efficiency of phosphate-buffered saline (PBS) (pH 7.4) and carbonate (pH 9.6) printing buffers were compared. While the various slides and surface chemistries showed differences in their binding isotherms, they ultimately reached similar levels of saturation. Silylated (aldehyde) slides showed comparable loading in both buffer systems. Apparently, tethering of antibody to the surface by Schiff s base formation of the surface aldehyde and lysine residues on the protein was applicable over a broad pH. However, carbonate buffer increased binding of proteins on silanated surfaces. 

Ketone 13 is apparently sensitive to overoxidation and the reaction mixture must be cooled to -78 °C before ozone is bubbled through it. Ozone addition must be stopped immediately after the blue colour of the ozone-saturated solution is detected. Another potential side reaction is the condensation of benzaldehyde with diketone 12 this reaction can be induced by overheating a concentrated solution of the crude product mixture. Accordingly, the residue from rotary evaporation obtained in step 10 of Protocol 7 should not be heated above 45-50 °C before benzaldehyde is removed completely by exposure to high vacuum and trituration of the residue with diethyl ether. 

The ability of certain soils to sorb the chemical strongly is important in analyzing residues of the chemical in soil. A procedure must be developed which will recover the chemical quantitatively from any soil. Table VII compares extraction from two soils, soil 3 which saturates with 4-amino-3,5,6-trichloropicolinic acid quickly and soil Bi which shows the slow takeup phenomenon. It is apparent that soil Bi, incubated 2 hours, holds the chemical more firmly than soil 3, incubated 5 days, but that hot water will remove most of the chemical from both soils. When soil Bi has been incubated for 28 days, removal of chemical was only 78.7% after three water washes, but further extraction with NaOH increased the recovery to over 99%. Several mild methods of extraction are compared in Table VIII. The same experimental techniques were used here but, instead of determining the extracted 4-amino-3,5,6-trichloropicolinic acid, the washed soil was assayed. A 50-mg. portion of dried, ground soil was suspended in a silica gel medium for scintillation counting and... 

It is apparent from the Xm values listed in Table V that capacities for adsorption of the organic pesticides on active carbon are quite large, greater on a molar basis than phenol and sulfonated 2-dodecylbenzene, and greater on a weight basis than any of the three other compounds. On the other hand, the fo"1 values, except for parathion, indicate approach to saturation adsorption only at relatively high residual concentrations. 

B. (5S)-(d-Menthyloxy)-2(5H)-furanone. A 500-mL, round-bottomed flask equipped with a magnetic stirring bar, 10-mL Dean-Stark trap, and reflux condenser is charged with d-menthol (51.9 g, 0.330 mol), 5-hydroxy-2(5H)-furanone (37.3 g, 0.370 mol), D-(-i-)-camphorsulfonic acid (3.96 g, 0.170 mol), and 190 mL of dry benzene (Note 8). The stirred suspension is heated to reflux under argon with an oil bath preheated to 100°C (Note 9). After 1-2 hr, a total of 5.1 mL of water is collected and no residual menthol is apparent by TLC analysis (Note 10). The reaction mixture is cooled in an ice bath and treated carefully with 100 mL of saturated sodium bicarbonate solution. After completion of the addition, stirring is maintained for 90 min as the mixture is allowed to warm to room temperature. The... 

The reduction in residual oil saturation versus equilibrium IFT is plotted in Figure 10.20, which shows that the Sor reduction was not correlated with the equilibrium IFT. Figure 10.21 shows equilibrium IFT versus acid number. Apparently, there was weak correlation between IFT and acid number when acid numbers were low. 

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