Schmidt’s rule

Category 2 concerns examples that satisfy Schmidt s rule but remain pho-toinactive. Table 8 records a few of such cases in which the distance between the reactive double bonds is less than 4.2 A. Scheme 9 shows the molecular structures. 

However the dissociation energies of the C3—H bond in propene-i and the C4—C3 bond in butene-1 are also particularly low (Table i8b Schmidt s rule). 

Intensive studies concerning topochemical reactions have been reported on the photodimerization of cinnamic acid and its derivatives. Schmidt and co-workers proposed a geometrical criterion for the photodimerization in the crystalline state that the reacting double bonds should be situated within about 4.2 A of each other and aligned parallel. In the case of the photoactive single crystal of 1-n-octylthymine obtained from acetonitrile solution (Form III), however, the distance between the reacting double bonds of the thymine bases was 4.47 A. It is difficult to apply Schmidt s rule to the photodimerization of the 1-n-octylthymine crystals. Therefore, it is necessary to determine the feature within the crystal of 1-n-octylthymine for the photodimerization reaction in the crystaUine state. 

During the interval between Vongerichten s and Schmidt s investigations, there were discovered several empirical rules through which the configuration of the a-carbon atom of many a-hydroxycarboxylic acids may be inferred. Schmidt applied three of these generalizations, the salt-acid rule and the phenylhydrazide and amide rules, to the appropriate derivatives of apionic acid Table I shows the comparisons which he published. 

Glitsch e rule of thumb (Table 8.6) for CMR random packings when the packing surface area exceeds 43 ft2/ft8. Both Ludwig (63) and the author like these rules, but they only apply to CMR 1, 1.5, and 2. To extend these rules to other packings, the author applied Schmidt s model (102). Equation (8.38) gives... 

Schmidt-Ott evidently approved of the idea to honour military technical services, but opposed giving the task to the KWG, on grounds of military secrecy. Concern about the KWG s discretion seems premature, as von Hamack had not yet delivered his famous critique of wartime profiteering, which was to produce long-lasting animosity in business circles, especially among munitions manufacturers. Besides, the KWG could have created a special commission, whose members were sworn to secrecy. Schmidt-Ott did not advance the more pointed criticism that the KWG lacked experts to evaluate military innovations and inventions. As a rule, the directors of the KWIs were scientists and not technical people or engineers. ... 

Once again, the oo subscript indicates the gas condition at far field from the liquid film, whereas the condition s refers to quantities evaluated at the film surface using the one-third rule. The specific heat capacity Cp is evaluated with the one-third rule, whereas Le indicates the Lewis number defined as the ratio between the thermal diffusivity and the molecular diflfusivity. This number can be also expressed as the ratio between Prandtl and Schmidt numbers ... 

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