Minimum threshold concentration

MTC — Minimum threshold concentration determined by statistical hypothesis testing methods. 

Fatty alcohol- (or alkyl-)ethoxylates, CoE, are considered to be better candidates for LLE based on their ability to induce rapid phase separation for Winsor II and III systems. (Winsor III systems consist of excess aqueous and organic phases, and a middle phase containing bicontinuous microemulsions.) However, C,E,-type surfactants alone cannot extract biomolecules, presumably because they have no net negative charge, in contrast to sorbitan esters [24,26,30,31]. But, when combined with an additional anionic surfactant such as AOT or sodium benzene dodecyl sulfonate (SDBS), or affinity surfactant, extraction readily occurs [30,31]. The second surfactant must be present beyond a minimum threshold value so that its interfacial concentration is sufficiently large to be seen by... 

The percolation model, which can be applied to any disordered system, is used for an explanation of the charge transfer in semiconductors with various potential barriers [4, 14]. The percolation threshold is realized when the minimum molar concentration of the other phase is sufficient for the creation of an infinite impurity cluster. The classical percolation model deals with the percolation ways and is not concerned with the lifetime of the carriers. In real systems the lifetime defines the charge transfer distance and maximum value of the possible jumps. Dynamic percolation theory deals with such case. The nonlinear percolation model can be applied when the statistical disorder of the system leads to the dependence of the system s parameters on the electrical field strength. 

The minimum inhibitory concentration (MIC) of azithromycin against many bacteria is 2 fig /mL. The dosing regimen in question 12 does not reach this threshold concentration in the plasma. Based on azithromycin s Vd of 31.1 L/kg, is it possible for the MIC to be reached within a patient s tissues ... 

Berg, H. W., Filipello, F., Hinreiner, E., and Webb, A. D. (1955). Evaluation of threshold and minimum difference concentrations for various constituents in wines. Food Technol. 9, 23-26. 

The parameter Cm can provide important data to be used in estimating the antifoam efficiency, in determining the minimum (threshold) surfactant concentration in the purification of solutions by foam flotation [53], in analysing the causes of foam formation in extraction systems and in establishing the optimum conditions of effective extraction [68]. 

Fig. 11.4 shows separately curve 1 from Fig. 11.3 which is the dependence of W on the DPPC concentrations in the AF. The W(C) curves allow to determine the threshold concentration C i.e. the minimum phospholipid concentration at which there is a 100% probability of observation of black films (see Eq. (3.130)). At concentrations lower than C, NBFs are no more observed, since W sharply decreases to zero (films rupture). At concentrations higher than C, (W = 1), NBFs always form. Special studies with phospholipid analysis of amniotic fluid indicate that of all phospholipids in the AF, it is the DPPC that stabilises the foam bilayers. This analysis gives grounds to conclude that the concentration of each phospholipid (except DPPC) in the native AF is of an order lower than the corresponding... 

The selection of the organic phase has a substantial effect on the minimum surfactant concentration necessary to obtain the inverse microemulsion. Nevertheless, there is a threshold for the minimum surfactant amount needed to form the small microemulsion droplets (d a 5-10 nm). Calculations give a limiting value of approximately 10% of all other components lower concentrations of surfactant lead to conventional macroemulsions. 

There are various ways to derive a calibration curve. Multi-point calibration curves, for example, include a minimum of three different concentrations of the analyte. For semiquantitative assays, a single-point calibration is common. The single point is usually the threshold concentration used to determine whether a specimen is positive or negative for the analyte of interest. Depending on the validation process and performance characteristics of the assay, a single-point calibration curve may also be used in quantitative applications over a limited range of linearity. A historical (pre-established) multi-point calibration curve may also be used, but only if the stability of the analytical method over time has been well established (Goldberger et al., 1997). 

So, the perfect fit of Haber s rule to the carcinogenic action of 4-DAB suggested that threshold concentration (c ) and minimum time of response (i ) were (in Clark s words) so small as not to produce a measurable error. 

As a threshold concentration, e.g. the minimum concentration of the compound in the air detected by the nose. 

In assembling his scientific information, McKee followed the innocent until proven guilty approach that Robert Kehoe had introduced in his studies of tetraethyl lead and that industry-friendly scientists had subsequently applied to synthetic pesticides. Only those studies that determined limiting or threshold concentrations were included in the compilation. When no minimum concentration was known below which a substance did not cause harm—as in the case of cancer-causing chemicals—McKee often omitted... 

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