Indicator saturation

The tantalum dissolution process takes longer compared to the preparation of the corresponding niobium solution, therefore the solution is heated and a small amount of nitric acid is added. A grey precipitate indicates saturation of the solution. The prepared solution is separated from the precipitate by filtration and used as the initial solution. 

These data are consistent with the results obtained by Barry (16) who investigated the influence of the preliminary treatment of a specimen of ZnO on the sign of the photoadsorption effect with respect to oxygen. The specimen was first calcined at a high temperature in oxygen and then cooled to room temperature, at which adsorption was subsequently carried out. The untreated specimens showed photodesorption, while on the samples treated by the procedure indicated (saturation with oxygen) there was observed photoadsorption. 

Bohle and co-workers (133) have demonstrated that varying the electronic and stereochemical properties of porphyrin substituents can strongly influence the rates of NO labilization (Eq. (11)). For example, the displacement of NO from Fe(TPP)(NO) by pyridine is many orders of magnitude slower than from Fe(OBTPP)(NO) (OBTPP = octabromo-tetraphenylporphyrin). An analysis of the kinetics of the latter reaction indicated saturation in [L], and the mechanism was suggested to involve reversible formation of Fe(OBTPP)(L)(NO) followed by NO dissociation (Eq. (50)). Clearly changes in porphyrin properties can lead to enhanced reactivity toward NO loss. 

Geochemical speciation modelling indicated saturation with respect to gypsum and several carbonates, slight under-saturation with respect to calcium arsenate (Ca3[As04]2) and ferrihydrite. 

When the rate of reaction is measured at fixed [E], but varying [S] and the results plotted, the Michaelis—Menten graph is obtained (below). This rectangular hyperbola indicates saturation of the enzyme with substrate. 

As a consequence of its high lipophilicity and low aqueous solubility, gastric acidity is also required for itraconazole absorption (Haria et al., 1996). It is best absorbed when administered with food, although there is considerable interpatient variabihty. The oral bioavailability or itraconazole from a 100-mg solution dose was 55%. Like ketoconazole, its bioavailability and half-life are dose-dependent, indicating saturable metabolism. Once absorbed, itraconazole is highly plasma protein bound (99.8%) and widely distributed (10.7 L/kg). Although itraconazole is widely metabolized, it does produce an active metabolite by hydroxylation of the triazolone side-chain. 

The appearance of turbidity indicates saturation of alkyl halide. In this way both sodium thiosulfate and 2-bromopropane are nearly in a one-phase system, thus shortening significantly the heating period. Furthermore, the competitive hydrogen bromide elimination and the ensuing acid-promoted decomposition of thiosulfate into sulfur and sulfur dioxide are minimized, the checkers added 300 ml. of water over a period of 90 minutes. 

Dioxane is rapidly absorbed upon inhalation or after oral administration, but its penetration of skin is poor. The major metabolite is (3-ln dro clhoxyacetic acid, which is rapidly excreted. In rats, the elimination of 1,4-dioxane and its metabolites is progressively delayed as doses are increased, indicating saturation of metabolism. 

Fig. 5. High resolution spectra of U Cephei In the Mg II resonance doublet region at 2975 and 2802 A, at phase 0.58, during its active mass flow episode in 1986 (McCluskey et al. 1987). The maximum-velocity toward the observer is about 800 km/s. The flat bottom of the broad absorption feature indicates saturation but the absorption does not quite reach zero-flux level, suggesting only a partial covering of the surface of the B star by the plasma flowing out of the G giant.

The solution behavior of surfactants can be illustrated with a curve of the air-water interfacial tension (the so-called surface tension yAW) vs. surfactant concentration Cw (Figure 17.2). An increase of Cw results in a decrease of yAW at low Cw until an inflection in the curve occurs. Beyond the inflection region, increasing Cw does not result in a change of yAW. The inflection indicates saturation of the water-air interface with surfactant molecules. Additional surfactant molecules cannot adsorb to the interface and are forced to remain in the water phase. 

Average of samples M-39 and M-26, Expedition Monsoon, by Mazor, Wasserburg Craig (1964). NB These data indicate saturation anomalies 20%, which would probably be considered questionable at present. 

The thermal or photochemical homolysis of the hydroperoxide leads to the formation of an alkoxy radical. The alkoxy radical is the precursor of unsaturated alcohols, acids and ketones. The decrease in intensity of the band at 807 cm-1 indicated saturation of the double bond, which could result from a radical addition to the double bond (for example, by reaction with the hydroxyl radicals resulting from the decomposition of hydroperoxides). Saturation reactions result in the formation of saturated alcohols, acids and ketones. 

Adsorbed amounts are commonly presented as an adsorption Isotherm, which is a plot of either or r as a function of the polymer solution concentration at a given temperature. Polymer adsorption typically leads to hlgh-afflnlty (H) Isotherms (see the classification in fig. 2.24). A typical example for a homodlsperse polymer is shown in fig. 5.7. As a rule considerable adsorption occurs even at extremely low concentrations, typically well below 1 g m 3. For somewhat higher concentrations, the Isotherm shows a nearly horizontal part, the pseudo-plateau (often simply referred to as "plateau ). Indicating saturation of the surface. For polydisperse polymers there is usually not such a well-defined pseudo-plateau, and a more rounded isotherm Is found (see sec. 5.3d below). 

Effective U(VI) removal is accomplished at all negative potentials. At a potential of - 0.3V, the Lf(VI) concentration in the effluent is reduced to Img/L in 2h and then increased continuously. At a potential of- 0.5 and - 0.9V, a complete removal of U(VI) is rapidly reached in Ih and maintained throughout the test. However, in case of OCP(open-circuit potential) the effluent concentration of U(VI) increased within 3h and finally reached the level of the feed, indicating saturation of sorption capacity by the ACF. From these results, it could be confirmed that the external negative potential exerted on the ACF electrode has great impact on the adsorption capacity of the ACF. 

Possibly the most widely employed charts are those of Nelson and Obert [7,2]. These contain graphs of Z as a function of reduced pressure, Py, and reduced temperature, Ty, for 0 < Py < 0.1 and 0.6 < T,- < 2.0 as a small-scale (1x1 in.) inset for 0 < P,. < 1, 0.6 < Ty < 5.0 and for larger ranges. No saturation-boundary curves are given, and the small-scale in.set is difficult to use. In general applications, the author has found the need for a low-pressure/low-temperature chart of "readable accuracy" with an indicated saturation boundary.. Also, some of (he Nelson/Oberl data may not be accurate. 

H2O <0.4-0.5 wt.%, t5fpicaUy 0.1-0.2 wt.% enriched mid-ocean-ridge basalt (E-MORB) up to 1.5 wt.% CO2 50-400 ppm typically saturated at emption (gas phase almost pure CO2) leading to vesiculation S 800-1,500 ppm immiscible Fe-S-O liquids indicate saturation at emption... 

FIG. 63. Equilibrium solubility of SO3 (wt.%) in melts of the system Si02—Na20 with component ratios of 4 to 1.5 at 1200 in terms of partial pressure of SO2 + O2. The dashed line indicates saturation (Holmquist, 1966). 

Subcutaneous administration leads to a peak heparin level 2 h after injection and an onset of anticoagulant effect within 1-2 h. Intravenous administration leads to an immediate peak heparin level with anticoagulant activity within 20-30 min. Heparin binds extensively to a number of plasma proteins. Its volume of distribution is 0.07lkg in adults. The pharmacokinetics of heparin is complex and incompletely understood. Heparin metabolism occurs primarily in the reticuloendothelial system by desulfation. The LMWH agents have longer half-lives than standard heparin. Heparin s elimination half-life increases disproportionately with increasing dose, indicating saturable kinetics. 

IAP is the ion activity product, i.e. the numerical product of ion activity in the water. An 2 value of 1 indicates saturation, values greater than 1 indicate supersaturation and values less than 1 indicate undersaturation. 

Geochemical computer modeling and the abundance of limestone indicates saturation of the groundwater with respect to anhydrite and calcite. Calcium, sulfate alkalinity, and TDS... 

FIGURE 11 Colors of the catalysts described in Figure 10. The progression from orange/ yellow to green indicates saturation of the support by Cr(VI) and subsequent decomposition to Cr(lll). 

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