Results of Other Methods

The use of a Shewhart chart enables the detection of whether or not a method is under quality control over time it is not, however, able to detect a systematic 

As pointed out in Chapter 2, all methods have their own particular source of error, e.g. for some techniques, errors may occur due to an incomplete derivatization, a step which is not necessary for other techniques such as high performance liquid chromatography (HPLC) the latter technique, however, may have errors such as incomplete separation which is not encountered, or to a lesser extent, in the former technique. 

An independent method should be used to verify the results of routine analysis. If the results of both methods are in good agreement, it can be concluded that the results of the routine analysis are unlikely to be affected by a contribution of a systematic nature (e.g. insufficient extraction). This conclusion is stronger when the two methods differ widely, such as derivatiza-tion/gas chromatography (GC)/atomic absorption spectrometry (AAS) and HPLC/inductively coupled plasma mass spectrometry (ICP-MS). 

If the methods have similarities, such as an extraction step, a comparison of the results would most likely lead to conclusions concerning the accuracy of the method of final determination, and not as regards the analytical result as a whole. 

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As mentioned, the data obtained by this method are expressed as cumulative size distribution curves. Since the computations assume Stokes law for spherical particles, the plotted curves give the distribution of spherical particles which would behave like the actual sample with respect to this experiment. For this reason, the sizes on the distribution curves should be labelled Stokes Equivalent Diameter . Because of the underlying assumptions and the above interpretation of the results, it is clear that the repeatability of this method has more meaning than accuracy of comparison with results of other methods... 

The oxide layer thickness can be determined in a number of ways. Direct microscopic observation has been demonstrated by Takahashi et aV9 Results of other methods can be made to agree... 

In Figure 17.12 we see four NMF thickness maps and spectra found in a highly weathered soil from a forest site in Kenya. While especially the regions found in the first shown component seem to be of special interest, the spectra need to be evaluated with caution. It is often unclear if the NMF algorithm found the global extremum of the cost function or did not move beyond a local extremum. The spectra found may not be close to reality. While the results can be better in many other cases, it is always worthwhile to compare them with the results of other methods or verify against additional information one might have. 

H and 2H NMR have been used in styrene-butadiene rubber (SBR) with and without carbon-black fillers to estimate the values of some network parameters, namely the average network chain length N. The values obtained from both approaches were checked to make sure that they were consistent with each other and with the results of other methods [71, 72, 73]. To this purpose, a series of samples with various filler contents and/or crosslink densities were swollen with deuterated benzene. The slopes P=A/ X2-X 1) obtained on deuterated benzene in uniaxially stretched samples were measured. The slopes increase significantly with the filler content, which suggests that filler particles act as effective junction points [72, 73]. 

There have been few AP-S studies of micas. However, a set of key papers by Raeburn et al. (1997a,b) demonstrated the untility of this technique for measuring Fe VZFe in thin sections. Accordingly, an Appendix is provided here to point the reader toward key references in this field, and comparions of XPS studies with results of other methods will be presented. 

Carbon-carbon double bonds oc9 / to the carbonyl group are not attacked, which contrasts with the results of other methods of reduction. Nitro groups, ester groups, and even activated halogen are unaffected. And a further advantage of the method is the generally good yields obtained. 

Many studies have addressed the time scales of different motions of DNA [84]. I delay consideration of optical probe methods until the next section and focus here on the results of other methods, especially those studies that examine sequence-dependent properties. 

The results of both methods, i.e. evaluation of the total curve and evaluation of sections of the curve are compared in Table 4-211. Although there are differences in the values, those obtained by evaluation of the four sections separately are closer to the results of other methods (Table 4-209). 

From the Table n, it can be found that no matter what type of asphalt, all basic units of asphaltene cells are the same size. No matter what solvent is used, the asphaltene micelle is ca. 10 nm, and is consistent with the results of other methods. 

Arson investigations The use of NMR spectroscopy has been reported to complement the results of other methods for analyzing debris from suspected arson cases. The type of accelerant used to start the fire can be identified by the relative sizes and shapes of the peaks in different regions of the NMR spectrum - the strictly aliphatic portion from 0 to 2 ppm, the aliphatic moieties attached to aromatic components from 2 to 3 ppm, and the aromatic region from 6.5 to 7.5 ppm. Thus, paint thinner, lighter fluid, kerosene, diesel fuel, and various brands of gasoline all give their own unique patterns. These patterns... 

An important question which can be raised is how the r-electron CCSD approximation in (hyper)polarizability calculations compare with the results of other methods, particularly with the ab initio and semiempirical all-valence methods. It is also important to compare obtained theoretical results with available experimental data. 

Since it was in our research interest to determine the conditions for the development of such a competence empirically, we conducted further analyses. For example, we needed to clarify how many students went through the desired process of development (Figure 9). As expected, only a small number of students were found in the class of model competence during the pre-test. Most students presented only inappropriate argumentation and, therefore, did not have model competency in accordance with our classification. During the post-test, the distribution shifted in the direction of the class of model competence. This means that the development of a modelling competency can be observed. The number of students who moved into the class of model competence correlates with the number of students who left the class of no model competence. As the results of the long-term test show, this effect can be sustained. This result of the latent-class analysis is in accordance with the results of other methods of evaluation... 

An exact determination of Dn and is not possible, but they can be estimated from results of other methods, for instance a TDB classes model in regions with few TDBs per chain. 

Multilayer adsorption and capillary condensation of gases within the narrow diameter pores below a few tens of nanometers can also be used to determine the pore size distribution and pore volume. It is believed that nitrogen cannot see the pores larger than ca. 50 nm in diameter in ordinary equipments. Therefore, the determination of total porosity should be done by combining the results of other methods, such as mercury intrasion, which can accurately detect larger pores. The lUPAC recommendation on the nomenclature of the mesopores , from 2 to 50 nm in diameter, reasonably corresponds to the size range that nitrogen adsorption can reliably cover. 

Thermodynamic integration provides an alternative approach to calculation of free energies, which is always useful for verifying the results of other methods. In some cases, it provides the only workable route to calculation of free energies, even if artificial integration paths must be devised. ... 

The direct MCS described above is the basic version of the method and is often used in the literature as an exact (reference) approach for validating the results of other methods (Adhikari 2011). Several variants of this approach (e.g., importance sampling, subset simulation, line sampling) have been developed in the last twenty years especially for the efficient solution of reliability problems where the calculation of small failure probabilities requires a very large number of samples. These variants will be examined in section Reliability of Stochastic Systems. ... 

PTMO/PA12 is not a lamellar system. This conclusion can be drawn from several consistency checks [68]. Thus, the layer thicknesses reported for this material should not be compared with other materials or with the results of other methods. Their constancy only confirms that the method of preparation does not change the size and arrangement of the domains in this material. 

In this chapter, we report calculations, using the lOS approximation, of reaction rate constants for the H + H2 and F 4- H2 chemical reactions. In the next section, we give the relevant expressions for the thermal rate constants of interest. Then in section III, we present the numerical results and compare with results of other methods (both theoretical and experimental). Finally, we give our conclusions in section IV. 

In this section we discuss the types of calculations made and sources of error in the results, and we make comparisons with results of other methods for the H + H2 and F + H2 reactions. In general, the integration over E -02. equation (1) requires that one both extrapolate a(m->n E g ) to energies at which actual scattering calculations were not made and interpolate, since calculations were made at a finite number of energies. This introduces error apart from that inherent in the fact that the approximate lOS method was used in the dynamical calculations. In order to obtain some estimate... 

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