Detectability definition

NRC. 1984. Nuclear Regulatory Commission. Lower limit of detection definition and elaboration of a purposed position for radiological effluent and environmental measurements. U.S. Report NUREG/CR-4007. 

Currie, L. A., Lower limits of detection Definition and elaboration of a proposed position. Anal. Chem., 40... 

Currie, L. A. "Lower Limit of Detection Definition and Elaboration of a Proposed Position for Radiological Effluent and Environmental Measurements" U. S. Nuclear Regulatory Commission, NUREG/CR-4007, 1984. 

Another important task is online control of Mo impurity in copper-bearing ore. Online LIBS analyzer enables to detect definitely even trace Mo concentrations in the hundreds of ppm range (Fig. 8.33). Correlation coefficients with laboratory data R of Cu, Mo and Fe are in 0.92-0.98 range, promising the possibility of process control in industrial online LIBS application (Gaft et al. 2014a). 

The field that generates these eddy currents is, by its nature, anisotropic, i e the eddy current signal response is directionally dependent on probe orientation. This can be used advantageously if one bears in mind that the corroded material one aims to detect usually displays random peaks and valleys, while man-made edges have a definite orientation. 

The advantages of this approach for part 3 of the standard lie in the fact that no specifications on geometrical magnifications need to be made since these parameters implicitly result from the demanded IQI detectability. Furthermore, the standard is open to additional applications. All that is needed is to the definition of the respective equipment class and a specification on the respective IQI sensitivities. 

The sinc fiinction describes the best possible case, with often a much stronger frequency dependence of power output delivered at the probe-head. (It should be noted here that other excitation schemes are possible such as adiabatic passage [9] and stochastic excitation [fO] but these are only infrequently applied.) The excitation/recording of the NMR signal is further complicated as the pulse is then fed into the probe circuit which itself has a frequency response. As a result, a broad line will not only experience non-unifonn irradiation but also the intensity detected per spin at different frequency offsets will depend on this probe response, which depends on the quality factor (0. The quality factor is a measure of the sharpness of the resonance of the probe circuit and one definition is the resonance frequency/haltwidth of the resonance response of the circuit (also = a L/R where L is the inductance and R is the probe resistance). Flence, the width of the frequency response decreases as Q increases so that, typically, for a 2 of 100, the haltwidth of the frequency response at 100 MFIz is about 1 MFIz. Flence, direct FT-piilse observation of broad spectral lines becomes impractical with pulse teclmiques for linewidths greater than 200 kFIz. For a great majority of... 

We have already mentioned that real-world data have drawbacks which must be detected and removed. We have also mentioned outliers and redundancy. So far, only intuitive definitions have been given. Now, aimed with information theory, we are going firom the verbal model to an algebraic one. 

Oxidation, (i) Dissolve 5 g. of potassium dichromate in 20 ml. of dil. H2SO4 in a 100 ml. bolt-head flask. Cool and add 1 ml. of methanol. Fit the flask with a reflux water-condenser and warm gently a vigorous reaction soon occurs and the solution turns green. The characteristic pungent odour of formaldehyde is usually detected at this stage. Continue to heat for 3 minutes and then fit the flask with a knee-tube (Fig. 59, p. 100) and distil off a few ml. Test the distillate with blue litmus-paper to show that it is definitely acid. Then apply Test 3 p. 350) for formic acid. (The reflux-distillation apparatus (Fig. 38, p. 63) can conveniently be used for this test.)... 

The distillate may contain volatile neutral compounds as well as volatile acids and phenols. Add a slight excess of 10-20 per cent, sodium hydroxide solution to this distillate and distil until the liquid passes over clear or has the density of pure water. The presence of a volatile, water-soluble neutral compound is detected by a periodic determination of the density (see Section XI,2) if the density is definitely less than unity, the presence of a neutral compound may be assumed. Keep this solution Si) for Step 4. 

Significance tests, however, also are subject to type 2 errors in which the null hypothesis is falsely retained. Consider, for example, the situation shown in Figure 4.12b, where S is exactly equal to (Sa)dl. In this case the probability of a type 2 error is 50% since half of the signals arising from the sample s population fall below the detection limit. Thus, there is only a 50 50 probability that an analyte at the lUPAC detection limit will be detected. As defined, the lUPAC definition for the detection limit only indicates the smallest signal for which we can say, at a significance level of a, that an analyte is present in the sample. Failing to detect the analyte, however, does not imply that it is not present. 

Normal distribution curves showing the definition of detection limit and limit of identification (LOI). The probability of a type 1 error is indicated by the dark shading, and the probability of a type 2 error is indicated by light shading. 

The definition of an association constant for an antibody—antigen reaction can become more complex if the antibody—antigen reaction iavolves a multivalent antigen, as is the case when a polyclonal antisemm is used for detection of an antigen. This type of multivalent binding is termed avidity and is defined by the equation ... 

Bismuth trioxide is practically insoluble in water it is definitely a basic oxide and hence dissolves in acids to form salts. Acidic properties are just barely detectable, eg, its solubiUty slightly increases with increasing base concentration, presumably because of the formation of bismuthate(III) ions, such as Bi(OH) g and related species. 

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