Confirmatory experiments

When the temperature was slowly raised, no reaction was observed until 20° C, at which time polymerization occurred. In confirmatory experiments, 1-bromopentane reacted quantitatively with Mg in 1 min at -78° C. The resulting Grignard reagent did not react with subsequently added ... 

Some such confirmatory experiments were carried out by Sir William Ramsay and Mr. Francis L Usher, and they also described an experiment with a compound of titanium. 

It is interesting to speculate whether confirmatory experiments on the Mg2+ system in acetone-water could be made using Mg resonance. It was concluded (6) that for K = 10 3 the distribution of 0t-° values would be that shown in Figure 20 and hence the interesting region where maxima in 0 values occur is experimentally inaccessible because of the extremely low water concentrations ( w... 

When evaluating the findings, both biological and statistical significance should be considered together. If the criteria mentioned above for the test item are not clearly met, the classification with regard to the historical data and the biological relevance should be discussed and/or a confirmatory experiment should be performed. 

After due consideration of the control experiments carried out in the studies on collagen and gelatin and of the fact that no 3-aspartyl linkages have been reported, it seems unlikely that any a —> 7 conversion has occurred. In the case of other proteins it also seems unlikely but, in view of the fairly low values obtained and the small but significant value given by poly-a-glutamic acid by the method of Haurowitz et al. (1957), confirmatory experiments using methods similar to those of Franzblau (1962) and Franzblau et al. (1963) are necessary before any definite conclusions can be drawn. 

Statistics provides methods by which good chemists will be able to do even better chemistry and the strategies proposed above will, hopefully, make the confirmatory experiment also a satisfactory experiment. 

A ferredoxin with a molecular weight of 6000 and seven atoms of iron per molecule was extracted from Clostridium pasteurianum and oxidised samples show similar spectra [29], although with some evidence for at least two iron environments. An S = i configuration was proposed, but the confirmatory experiment of applying a magnetic field and looking for magnetic effects has not yet been carried out. 

Synchronized cultures of Chlorella ellipsoidea were used as a model system to identify biochemical modes of action of two herbicides/ butamiphos (0-ethyl--0-(3-methyl-6-nitropheny1)-N-sec-buty1-phosphorothioamidate, formerly coded S-2846), and chlorpropham (isopropyl inch lorocarban il ate). Cell cycle studies showed that butamiphos inhibited cell division, whereas its effects on respiration and general biosynthesis were slight. Confirmatory experiments with onion root apices showed that mitosis was blocked at the metaphase and that the spindle apparatus was disrupted. 

This comparison of linear and quadratic models is a good occasion to remember that empirical models are local models, that is, models that can only be applied to specific regions. This characteristic makes extrapolation a very risky endeavor. We only have to remember that the linear model was shown to be quite satisfactory for the first set of values, but the small extension of the temperature range made it necessary to employ a quadratic model, even though the data in Table 5.1 are aU contained in Table 5.4. Even this second model should not be extrapolated, and we do not have to go far to appreciate this. If we let, for example, T =20°C in Eq. (5.34), which represents only 10 °C less than the lowest temperature investigated, we obtain y — -24.44%, an absurd value, since negative yields are meaningless. In short, we should never trust extrapolations. If, even so, we dare make them, they should always be tested with further experiments, called for this reason confirmatory experiments. 

As mentioned earlier, the OA mainly serves the purpose of screening the vital few from the trivial many. In order to reach a solid and meaningful conclusion, more thorough confirmatory experiments are required. Take the weight-watch experiment as an example. It is recommended that the focus be... 

Once a satisfactory model is developed, separate stress-rupture (confirmatory), experiments will be performed to examine the model s predictive capability. 

Raquet and Pinte proposed a rapid modification of the iodometric method which, in confirmatory experiments, has given good results with solutions of pure hypophosphites but it has been found that more borax solution is required than is recommended by the authors. The amended method is ... 

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