Results from Different Methods

By the dry distillation of trimethyl - thujylammonium hydroxide, Tschugaeff obtained a thujene quite similar to the above, but of considerably higher optical rotation. He therefore considers that two stereoisomers may result from different methods of preparation from thujone. 

Tab. 3.14 Summary of analytical results from different methods for the determination of PAHs in SRM 1649a, Urban dust... 

It should be noted that discrepancies amidst available data may result from different methods of determination. For example, selected hydrodynamic radii of PAMAM dendrimers of Table 14.1 were obtained by two different experimental methods for generations 1 through 4 by dilute solution viscometry, while for generations 5 through 10 by size exclusion chromatography. 

Besides the mathematical outline, the methods are applied to real data examples from chemometrics for supporting better understanding and applicability of the methods. Prerequisites and limitations for the applicability are discussed, and results from different methods are compared. 

Model systems tests have played an important role leading to our understanding of protein functionality in food systems. There is no si ngle test that is applicable for all food systems. Careful consideration must be given when designing a model system and selecting a specific protein functionality test for a particular application. Comparison of results from different methods and from other laboratories must be made with caution. Similarly, extrapolation of results from model systems to real food products must also be carefully interpreted. 

Comparing the results from different methods of analyzing the data in Table 6, it can be seen that they generally agree on the ordering of effects, namely, 15, 12, 19, 4, and 10, but that they lead to different decisions about which factors should be declared active and which should not. 

Pacifici and Viani, commenting on comparisons among results from different methods applied to protein binding, warn that methods for drug binding need to be standardized. Currently, results depend greatly on technique and interpretation of results thus, experimental details such as anticoagulant used, type of dialysis or filtration membrane, buffer characteristics, duration of experiment, and temperature should be taken into account. 

Convert r values to a common type before making detailed comparisons between results from different methods. 

Similar situations exist for other methods. If quantitative theories are applied to data interpretation, all peculiarities of a method have to be considered. However, this does not allow a direct comparison of experimental results from different methods, because the time scales are different and depend on the specific experimental conditions. A solution to this problem is the determination of the effective surface age, which then allows a direct comparison between experimental data independent of their origin. 

In seawater systems, the oxidation method chosen for analysis of the organic carbon depends on the fraction (DOC, POC or VOC) of interest, the origin of the sample, and the type of information required. However, analytical results from different methods cannot be compared readily. By examining these various analytical methods for the measurement of the dissolved, particulate, and volatile fractions of the organic matter, the sources of the differences in the reported results may be better understood. 

Quantum chemical analysis of the correlations between the structure of arenium ions and their aptitude to rearrangements (see ) Quantum chemical calculations of activation parameters for 1,2-shifts of R in 1-H-l-R-benzenium ions give so far rather approximate results. Indicative in this respect is the discrepancy of results from different methods in estimating the relative stability of the unsubstituted ben-zenium ion and the jt-complex in which the added proton is located over one of the ring C—C bonds. Calculations on the CNDO/2 approximation point to a greater stability of the it-structure with a three-centre bond whereas those by the CNDO/2-FK and MINDO/2 methods and non-empirical calculations with... 

Comparison of results from different methods (a) N-acetyl L-alanine N-methyl amide ... 

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