Reproducibility quantitative

HPLC-UV is a popular technique to analyse textile dyes extracted from polyester fibres [697], acidic dyes from wool fibres [698] and basic dyes from acrylic fibres [699]. HPLC provides better sensitivity and resolution than TLC [697-699]. GE-RPLC has been used for the determination of 18 disperse dyes (e.g. Navy D-2G-133, Orange CB, Yellow D-3R and Red D-2G) extracted from polyester [700]. Compared with the traditional TLC method, HPLC offers lower detection limits, better observation of contaminant peaks, and reproducible quantitative results. HPLC has also been used to determine azo dyes [701,702]. 

Specht et al.60 Microdissected cancer tissues RNA lysis buffer containing SDS and proteinase K Real time, for seven cancerrelevant genes Reproducible quantitation of specific mRNAs can be achieved... 

This is considered to be largely a qualitative technique. Difficulties that arise in obtaining reproducible quantitative data are similar to those encountered in thin-layer chromatography. In addition, adsorption characteristics of dyes on macromolecules are so variable that only semiquantitative comparisons can be made. These are, however, still very useful... 

Thus our calculations not only reproduce quantitatively the results of two extensive experimental studies but also show very clearly why it is that 9 is favoured over 8. Since the total cost of our work (1 month by a Postdoctoral Fellow, Dr. Wolfgang Schoeller, plus 5 hours time on a CDC 6600 computer) amounted to about 20 000, DM, i.e. a small fraction of the two experimental studies referred to above, one can see that. MO theory can already compete with experiment, at least in possibly favoured cases as this. 

Dc arc 220 3-30 Most sensitive, least reproducible, quantitative analysis trace element quantitative analysis. 

It is interesting that, in the experiments by Taylor et al. [90] after the repetition of the same standard experimental run (increase and then decrease of temperature), the hysteresis peculiarities of kinetic curves were preserved but not reproduced quantitatively. Apparently, this is also associated with the fact that the time to achieve a steady state was insufficient. It could also be due to the slow mass transfer processes between surface and bulk. 

A model based on a modified mixing rule for the Peng-Robinson equation of state was able to reproduce quantitatively all features of the observed phase equilibrium behavior, with model parameters determined from binary data only. The use of such models may substantially facilitate the task of process design and optimization for separations that utilize supercritical fluids. 

Normalize the wave functions of the 2A2 and 2B, states of allyl radical (Eqs. 7.2 and 7.3 in the main text) by assuming zero-overlap between AOs. Then calculate the weights of each determinant by squaring their coefficients. From these reproduce quantitatively the spin density distribution for both states, given qualitatively in Fig. 7.3b. 

An important point is determining to what extent these results relate to actual biodegradation potential of the compounds concerned. In other words, could the regression models be considered QSBRs. This is of particular significance because a lack of reproducible quantitative data on biodegradation is one of the factors that limits the development of QSBRs (Degner et al., 1991). 

The experimental diffusion coefficient is reproduced quantitatively and the dielectric relaxation time is the same as that calculated by Watanabe and Klein for SPC/E [67]. 

If the number of minima of the potential energy surface (PES), with the corresponding geometry, and the vibrational frequencies obtained from a very accurate and complete ab initio calculation [182] is compared to the corresponding data of the models mentioned above, it appears that none of them is able to reproduce quantitatively these features of the PES. In particular, PSPC (polarizable SPC) and POLl underestimates the number of minima. The frequency assignment is however the same for all models, except for a few empirical potentials such as KJ, POL, POLl and PSPC. Better results for shear modes have been obtained with NCC and from the A bending with ASP-W4. 

The same conclusion about transferability is reached by Wallen et al [205] in a MD study of a supercritical Br solution. The ion-water interaction, described by a simple (LJ+Coulomb) two-body interaction augmented by the atomic polarizability of the ion [102] and the POLl model of water appear inadequate to reproduce quantitatively the change occurring in the solution when temperature and pressure rise to the supercritical region. 

The extraction efficiency is related to the slope of the extraction curve, so if the extraction is linear, E is constant and less than 100%. By careful calibration and keeping the experimental parameters constant so that the system is kinetically stable, repeatable values for Ee and E can be obtained. This will give reproducible quantitative results and most of the applications of membrane extraction to practical analyses are in fact based on this principle. 

Electronic structure calculations at the SCF level were applied to CO2-HF and CO2-HCI with the following results. The CO2-HF and CO2-HCI blue-shifts were reproduced quantitatively 9.9 and 3.9cm , respectively (experimental) versus 9.7 and 3.9cm , respectively (theoretical). The linear hydrogen-bonded equilibrium structures were also confirmed, with little... 

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