Concentration vs. time

Finally, preliminary diagnostic evaluation criteria, based on preventive identification of critical areas of interest on the monitored item, spatial concentration of localized AE events as compared with average AE event density and evolution of local event concentration vs time and/or plant parameters, have been worked out and submitted to extensive testing under real operation conditions. Work on this very critical issue is still to be consohdated. 

The decomposition data forjNO plotted as the reciprocal of concentration vs. time. This graph is linear, with a slope equal to the second-order rate constant. 

Bioavailability was assessed from measurement of the area under the curve (AUC) of whole blood lead concentration vs time (Blood AUC) or from measurements of the lead concentrations in bone, kidney or liver (the arithmetic mean of the three tissues is shown in the table). Data are from Casteel et al. (1997) and EPA (1996a, 1996b, 1996c). 

Figure 1. Flocculation. Experimental and theoretical particle concentration vs. time. Initial dose in OFC units beside curves. Molecular weight 1x10, charge density 95%. Shear rate 1800 s-. ...

FIGURE 7.3. Schematic outline of the DO concentration vs. time measurements for the determination of OUR values. 

The elimination constant for a chemical in plasma. Typically calculated using the formula Kel = — ln[10] x b where b is the slope of the linear regression line of the log of the mean plasma concentrations vs. time from the tmsx to 24 hours. 

The third proposed explanation for parabolic kinetics is that dissolved products may be released from the mineral surface linearly, but that non-linear precipitation of secondary minerals from solution accounts for the non-linear concentration vs. time behavior (16). 

Fig. 3 a - c. Schematic diagram illustrating the decreasing source method for diffusion transport determination of any organic pollutant in solution or leached from complex mixtures, as follows a column setup b pollutant concentration vs time in source and collection reservoirs during the test c pollutant concentration in solid-pore water with depth from source after the test... 

Abstract Removal of the pesticide metobromuron from aqueous solutions by adsorption at the high area activated carbon cloth was investigated. Kinetics of adsorption was followed and adsorption isotherms of the pesticide was also be determined. In kinetic studies a special V-shaped cell with an UV cuvette attached to it was used for adsorption processes. With this cell it was possible to follow the concentration of pesticide molecule by in situ UV spectroscopy as it is adsorbed at the activated carbon cloth. The obtained absorbance vs time data were converted into concentration vs time data and these data were treated according to pseudo-first-order and psendo-second-order kinetic models. Adsorption of that pesticide was fonnd to follow second-order kinetic model with k 87.35 g mol min. Adsorption isotherms were derived at 25°C on the basis of batch analysis. Isotherm data were treated according to Langmuir and Freundlich models. The fits of experimental data to these equations were examined and founded that the adsorption isotherm was well represented by Frenndlich model. 

AUC, area under the concentration vs time curve N/A, not applicable. 

Rate laws can be derived by measuring concentration variations as function of time or the initial rates as function of the initial concentrations. Unfortunately, there is no general method for finding the rate law and the reaction order from measurements of concentration vs. time or other types of measurements. Usually, a trial-and-error procedure is used, based upon intelligent guesses. 

Try to fit an nth-order rate equation to the concentration vs. time data of Example 3.1. 

Fig. 6. Simulated plasma drug concentration vs. time curves after intravenous administration (a) showing the j-axis in numeric scale, and (b) showing the curve when the v-axis is converted to logarithmic scale.

Fig. 13. Plasma drug concentration vs. time curve after administrations of multiple oral doses at 8-hour intervals.

The mass transfer coefficient in liquid membrane, k , can be obtained from the plot of concentration vs. time. 

Figure 5.2 Plasma concentration curve of drug after single and repeated administration Csj. nax, maximal steady-state plasma concentration after repeated administration Css av, average steady-state concentration after repeated administration Css mm- minimal steady-state concentration after repeated administration n. maximal plasma concentration after single oral dose t Inax. time to maximal concentration after single oral dose t plasma half-life after single oral dose AUC, area under the concentration vs. time curve...

Fig. 1.4.3 Drug concentration vs time curve of repeated dosing.

Figure 5. Variation of monomer concentration vs. time for different values of initiator concentration calculated from appearance of polymer (O) calculated from disappearance of monomer (9).

The pulmonary delivery of rhG-CSF (18.8 kDa) and two PEG conjugates of rhG-CSF (PI, 81.5 kDa and P2, 146.8 kDa) was investigated in rats (Niven et al. 1994). Comparison of white blood cell responses after IT instillation of 500 pg/kg PI and P2 and rhG-CSF alone, demonstrated a greater response for more substituted PEG-rhG-CSF than rhG-CSF alone. The plasma concentration vs. time curve showed... 

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