Experimental checking

The evaluation of the deconvolution results show that time resolution is better or equal to 1 with the chosen processing time unit of 0.08 microseconds (respectively a rate of 12.5 MHz). First signals processed conservatively have been acquired with a samplerate of 12.5 MHz. A Fourier analysis shows that the signals spectras do not have energy above 2.0 MHz. This means that a sampling rate of 4.0 MHz would have done the job as well. Due to the time base of the ADC an experimental check with a sample rate of 5.25 MHz has been carried out successfully. 

As a consequence of these simple deductions, Graham s experiments c effusion through an orifice came to be regarded as one of the earliest direct experimental checks on the kinetic theory of gases. However, a closer examination of his experimental conditions reveals that this view is mistaken. As mentioned earlier, his orifice diameters ranged upwards from 1/500 in., while the upstream pressure was never very much less thai atmospheric. Under these circumstances the molecular mean free path len ... 

A computer assisted approach of heterocyclic structures (825, 826) predicted a new method of synthesis for the thiazole (826). This method was reported soon after by P. Dubs (807). The same program proposed two other methods not yet experimentally checked (827). 

Refinement. The recychng of the procedure to obtain better predictions as indicated by experimental checks. 

STANDARD SAMPLES AND EXPERIMENTAL CHECKING OF COMPETENCE OF ANALYTICAL LABORATORIES... 

Environmental analytical association Ecoanalytica produce standai d samples during last 12 years. Two topics will be discussed. The first is the principles of development of staictures and maintenance of quality of standai d samples. The organization of manufacture and maintenance of their stability ai e considered too in the report. Besides them authors consider scientifically-methodical aspects of preparation of samples for experimental check of technical competence of analytical laboratories and also samples for interlaboratory tests. 

The validity of the above conclusions rests on the reliability of theoretical predictions on excited state barriers as low as 1-2 kcal mol . Of course, this required as accurate an experimental check as possible with reference to both the solvent viscosity effects, completely disregarded by theory, and the dielectric solvent effects. As for the photoisomerization dynamics, the needed information was derived from measurements of fluorescence lifetimes (x) and quantum yields (dielectric constant, where extensive formation of ion pairs may occur [60], the observed photophysical properties are confidently referable to the unperturbed BMPC cation. Figure 6 shows the temperature dependence of the... 

In order to go further into the experimental check we constructed Arrhenius plots of the fluorescence quantum yield of BMPC in a few solvents (methanol, ethanol, propanol, hexanol and methylene chloride), all of which showed good linearity. The activation energies and A/kp ratios, calculated from the slopes and intercepts of those plots, are collected in Table 1. The smooth increase of both parameters in the alcohol series is mainly associated with the increase of solvent viscosity. On the other hand, decrease of the solvent dielectric constant from 32.7 (methanol) to 8.9 (dichloromethane) causes a small but significant increase of the activation energy also, this increase is probably somewhat compensated by the decrease of the viscous-flow... 

Finally, mention should be made of the two effects of interaction of the mathematical model whose negative coefficients show minima of flashpoints for the binary butanol/cyclohexanol and butanol/pentanol combinations. Can they be explained by the presence of azeotropes in these substances The tables examined did not list these mixtures and there was no time to do an experimental check with the students. 

Analytical measurement Pros - Results obtained reflect well reality - Repeatability and reproducibility of results (at least between good qualified labs) - Measurements are independent of information/data sources - Multipurpose analytical methods can cover many compounds on a single run - Even the best model will ultimately need to be experimentally checked - Discovery of new emerging contaminants is possible... 

If the energy is transferred by trivial emission/reabsorption, it will lengthen the measured lifetime of the donor emission, not shorten it as happens in resonance energy transfer. This comes about because intervening absorption and emission processes take place prior to the final fluorescence emission (the reabsorption cannot take place until the photon has been emitted) the two processes do not compete dynamically, but follow in a serial fashion. In FRET, such an emission/reabsorption process does not occur, and the fluorescence lifetime of the donor decreases. This is an experimental check for reabsorption/reemission. 

In order to experimentally check the validity of the time-dependent diffusion theory as applied to the closed-can method, extensive systematic investigations of radon exhalation, with carefully controlled parameters, are needed. To the author s knowledge no such investigations have yet been performed. 

It is noteworthy that for betaines X = 0, NMe E14 = Ge, Sn E15 = P Wittig type decomposition becomes kinetically and thermodynamically the most favorable process. In the case of betaine Me3P( + )-CH2-GeMe2 0( ), the activation energy of germene Me2Ge=CH2 formation is only 5.5 kcal/mol. These conclusions need experimental checking. 

Zukoski [16] has shown theoretical results that have stood the test of many experimental checks for the temperature and descent of a uniform smoke layer in a closed, but leaky (Ap 0), compartment. Similar to the scaling used for the ceiling jet, he found that... 

The recognition of the two fundamental mechanisms of reptation and arm fluctuation for linear and branched entangled polymers respectively allows theoretical treatment of the hnear rheology and dynamics of more complex polymers. The essential tool is the renormahsation of the dynamics on a hierarchy of timescales, as for the case of star polymers. It is important to stress that experimental checks on well-controlled architectures of higher complexity are still very few due to the difficulty of synthesis, but the case of comb-polymers is an example where good data exists [7]. 

An experimental check of the conclusions of the theory was. performed for neutral PAA gel and also for a weakly charged PAA network containing 1.88 mol % of the anionic SMA links synthesized in dilute solution of monomers. The mixtures of water with dioxane, ethanol, and methanol were used as a solvent [48]. 

For an experimental check of the correctness of this theoretical value see the measurements on sharp fractions (Section 3.8.2). 

A quantum mechanical calculation of the Penning electron energy spectra for the two different potentials would be quite interesting. A comparison with recent high-resolution results (2) would give an independent experimental check on the existence or nonexistence of the maximum in the potential. 

An experimental check on this assumption about activity coefficients is possible over a limited range of solvent acidity. If the composition of water-sulfuric acid mixtures is varied over the range in which all four species, Al5 A2, A1H +, and A2H+ are present in appreciable concentration, then, since OAlH + / aA2H+ 1S (W definition) constant, a constant ratio [A1][A2H+]/ [A2 [A1H + ] implies that the assumption of the ratio of y s being constant is correct in this range of solvents. Experimentally, for bases that are substituted anilines this test is fairly successful, a result that supports the validity of the method. The question of how similar two compounds must be to be sufficiently close in structure will be considered later. 

Acknowledgements The authors wish to thank Prof. A. I. Leonov for his help in the establishing of the theoretical part of this work, Dr. A. N. Prokunin for his valuable assistance in studying the rheological properties of plastisols and helpful discussions of mathematical modelling, and Dr. V. A. Teleshov who has provided the possibility of experimental checking of theoretical predictions. 

Experimental checking by analyzing thermally degraded samples. 

Table 4.9 Experimental check of the method with IAEA samples...

As we said, QSAR is a possible tool to explore toxicity. Other tools have clear advantages because they refer to an experimental check of the result. New in vivo tools will be developed, useful to investigate toxicity phenomena, and many in vitro... 

The types of information that can be extracted are illustrated by a typical experiment involving, say, transitions between the 1s2s3S state and the fine structure levels of the ls2p3Po)i)2 manifold of states. The total transition frequency gives the QED shift, for which theory is not yet fully developed and experimental checks are very valuable. However, if one measures the 3He - 4He isotope shift for the same transition, then the QED uncertainty largely cancels, allowing the differential nuclear radius to be accurately determined. If one measures... 

To further improve the accuracy of our FS measurements, the frequency stability of the master laser and the S/N of the 1083 nm helium transitions must be increased. In this way, not only the statistical uncertainty will be improved, but it will also allow a precise experimental check of systematic effects. 

The above statement is therefore a postulate, which goes considerably beyond the possibility of an experimental check. Our observations cannot tell us anything about what the sequence of state of an actual isolated gas quantum would be over a very long period of time and whether it would satisfy the principle of determinacy. 

In principle, Fig. 26.18 permits the prediction of solvent behaviour. The essential difficulty is the choice of proper values of the solubility parameter components 5vP and 8hP for a given polymer. A fair estimation is possible by means of the methods of Hoftyzer-van Krevelen and of Hoy, described in Chap. 7 (see in particular Eq. (7.25)). An experimental check remains desirable in all cases. 

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