Apparent level

Fig. 12.4 illustrates the complex interactions induced by the presence of silica between reaction temperature, sulphuric acid acidity and the apparent level of phosphorus found. By careful control of acid concentration and reaction temperature, interference by silica can be minimized. Arsenic, germanium and bismuth would interfere in the method but not at the low levels normally encountered in sediment in water samples. 

The statistical theory of crosslinking used in the last section also gives the theoretical concentration of elastically-active chains, N, which in turn determines the rubbery modulus E = 3NRT (R is the gas constant and T is the absolute temperature). At 70% reaction one calculates E - 2 x 10 dyn/cm1 2 3 4 5 6 7 8 9 10, in agreement with the apparent level in Figure 1. 

This discrepancy between the apparent level, in the gauge glass, and the actual level (see Fig. 6.1), in the tower, also occurs in any other type of level-measuring device. This includes external float chambers, kidneys, displacement chambers, and level-trols. The one exception to this is level-measuring devices using radiation techniques. 

Figure 6.5 is a plot of the liquid level in a crude preflash drum versus time. We were steadily withdrawing 10 percent more flashed crude from the bottoms pump, than the inlet crude feed rate. The rate of decline of the liquid level noted in the control center was only about 25 percent of our calculated rate. Suddenly, when the apparent level in the control room had reached 40 percent, the level indication started to decline much more rapidly. Why ... 

This extreme nonlinear response of a level, to a step change in a flow rate, is quite common. Before the sudden decline in the liquid level, foam had filled the drum above the top-level tap. The initial slow decline in the apparent level was due to a dense foam dropping between... 

Extractions The apparent level of grafting, polymer loading and conversion was determined by Soxhlet extraction using dimethyl formamide. The oven dry weight was corrected for pulp lost in the mercerization step. Grafting parameters were defined as follows ... 

A completely different result comes out if one pursues the experimental course of Fig. lib. The variation of the apparent diffusion coefficient as a function of quench depth AT = T — Ts, where Ts is the spinodal point, is shown in Fig. 13. Initially, the apparent diflusity increases with increasing quench depth AT which is in accord with the mean-field theory since (% — Xs)/Xs AT. However, when the quench depth is raised further the apparent diffusion coefficient starts to decrease and finally, apparently levels off. 

Identification of impurities present at an apparent level of not more than the identification threshold is generally not considered necessary. However, analytical procedures should be developed for those potential impurities that are expected to be rmusuaUy potent, producing toxic or pharmacological effects at a level not more than the identification threshold. All impurities should be qualified ... 

This measure of the formation of hydroxyl groups, shown in Figure 6, Indicates an apparent leveling off at times greater than about 2000 hours exposure. This may be related to the change in rate of ester loss but the uncertainty of FTIR measurement in the region of 3000 to 3600 cm does not permit a more rigorous interpretation of the behavior. 

Rich, K.A., Codina, J., Floyd, G., Sekura, R., Hildebrandt, J.D. and Iyengar, R. (1984). Glucagon-induced heterologous desensitization of the MDCK cell adenylyl cyclase Increases in the apparent levels of the inhibitory regulator. (Nj). ]. Biol Chem., 259, 7893-7901... 

Problems associated with identification of specific regulatory mechanisms can be illustrated by a brief consideration of changes in the apparent levels of aspartate kinase during plant growth. Aspartate kinase extracted from whole carrot roots, freshly sliced root tissue, or recently subcultured cell suspensions is predominantly sensitive to inhibition by the pathway product, threonine. However, when root slices are incubated in a growth stimulating medium or when suspension cultures are allowed to grow for a period of time, the bulk of the extractable aspartate kinase activity is sensitive to... 

Thermal treatment in the DSC does not increase the apparent level of crystallinity or allow the semi-crystalline copolymers to recrystallize. Surprisingly, compression molding has induced order into sample II-l (Table 2). In this case the level of order was sufficient to embrittle the block copolymer material. Treatment with liquids also provides a means for increasing the level of crystallinity in the copolymers, as was noted earlier for the hydroquinone sulfone system (8). Scanning electron microscopy results which show this effect are given in Figure 4. 

Although studies have shown that oxygen, sulfur, and nitrogen may greatly affect the rates of solvolysis reactions, these results indicate that the electron-withdrawing groups at C-3 apparently level the participatory power of... 

The PBT Profiler software determines, as the name implies, if a chemical could be considered to be persistent, bioaccumulative, or toxic. The profiler highlights chemicals at two apparent levels of persistence those with a half-life in water, soil, or sediment between two and six months, and those with... 

In the main steam generators. As the coolant on the secondary side is boiled, liquid-level controls open feed water control valves from the condensate pump discharge header to maintain this level. Since liquid level will be extremely difficult to determine due to the large steam fraction, the apparent level will be compensated by steam flow and pressure signals and manually biased as necessary for stable level control. 

Apparent level This is the liquid level that appears in the gauge glass or is displayed on the control panel. 

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