Small table method

Method (7) is a small table method. In the rotary table methods such as (2), (3), and... 

Table 3. Solubility Parameters of Acrylic Homopolymers Calculated by Small s Method ...

Small table type Wafer center covers the center of a table. The wafer is set face down. This method conserves space. Slurry is generally introduced from the lower side of the table. The orbital type shown in Fig. 3.3 is one of these categories. 

Results. The slurry method of analysis of wear oils can give reproducible results when compared with the bomb combustion method (Table 5.19). The random selected metals analysed for this sample were used to show that this method could be used as an alternative provided that the particle sizes of insoluble suspensions in the oil are suitably small. This method may be an alternative to sample preparation by tedious destructive methods. 

Quite recently Eucken and Schwers (84) have made some measurements with the vacuum calorimeter, which were planned particularly to test the TMaw of Debye (cf. following chapter) in view of this object the highest accuracy was wanted at the lowest temperatures (in thermodynamical calculations the specific heats are of subordinate importance in this region because of their smallness). The method used was essentially that described above the heating was done, however, with a constantan wire, while the measurements of temperature were made by means of a lead wire, the resistance curve of this material at very low temperatures being of a more suitable form than is the case with platinum. From the measurements of Kamerlingh-Onnes and Clay the following table was calculated by the above-mentioned authors, and was related to the sample of lead used by them by correction with the aid of the a-rule (p. 36). 

Table 4.16 shows the results of this new method for an example. They differ significantly from those obtained with the method proposed by Riazi for the initial and 10% volume distilled points. The accuracy is improved and the deviations observed at small distilled fractions are corrected. 

In addition to the orthodox method, just described, for the determination of the boiling points of liquids, the student should determine the boiling points of small volumes (ca. 0 5 ml.) by Siwolobofifs method. Full details are given iri Section 11,12. Determine the boiling points of the pure liquids listed in the previous paragraph. Observe the atmospheric pressure and if this differs by more than 5 mm. from 760 mm., correct the boiling point with the aid of Table II,9,B. Compare the observed boiling points with the accepted values, and draw a calibration curve for the thermometer. 

Dewar and his co-workers, as mentioned above, investigated the reactivities of a number of polycyclic aromatic compounds because such compounds could provide data especially suitable for comparison with theoretical predictions ( 7.2.3). This work was extended to include some compounds related to biphenyl. The results were obtained by successively compounding pairs of results from competitive nitrations to obtain a scale of reactivities relative to that of benzene. Because the compounds studied were very reactive, the concentrations of nitric acid used were relatively small, being o-i8 mol 1 in the comparison of benzene with naphthalene, 5 x io mol 1 when naphthalene and anthanthrene were compared, and 3 x io mol 1 in the experiments with diphenylamine and carbazole. The observed partial rate factors are collected in table 5.3. Use of the competitive method in these experiments makes them of little value as sources of information about the mechanisms of the substitutions which occurred this shortcoming is important because in the experiments fuming nitric acid was used, rather than nitric acid free of nitrous acid, and with the most reactive compounds this leads to a... 

This method is exemplified by its application to quinoline, isoquinoline, cinnoline, and isoquinoline 2-oxide, which are nitrated as their conjugate acids. The rate profiles for these compounds and their N- or O-methyl perchlorates show closely parallel dependences upon acidity (fig. 2.4). Quaternisation had in each case only a small effect upon the rate, making the criterion a very reliable one. It has the additional advantage of being applicable at any temperature for which kinetic measurements can be made (table 8.1, sections B and D). 

The most obvious sensor for an acid-base titration is a pH electrode.For example, Table 9.5 lists values for the pH and volume of titrant obtained during the titration of a weak acid with NaOH. The resulting titration curve, which is called a potentiometric titration curve, is shown in Figure 9.13a. The simplest method for finding the end point is to visually locate the inflection point of the titration curve. This is also the least accurate method, particularly if the titration curve s slope at the equivalence point is small. 

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