Gerhardt

First prepared by C. F. Gerhardt from ben2oyl chloride and carefully dried potassium acetate (1), acetic anhydride is a symmetrical iatermolecular anhydride of acetic acid the iatramolecular anhydride is ketene [463-51-4]. Benzoic acetic anhydride [2819-08-1] undergoes exchange upon distillation to yield benzoic anhydride [93-97-0] and acetic anhydride. 

C Hg, and quartine, C H. These are known as the Hofmann-Gerhardt names. 

A. Garg, L. Gerhardt, and E. Gulari, Proceedings of the Second International Symposium on Supercritical Fluids Boston, Mass., 1991. 

Phenolic resins were the first totally synthetic plastics invented. They were commercialized by 1910 [I]. Their history begins before the development of the structural theory of chemistry and even before Kekule had his famous dreams of snakes biting their tails. It commences with Gerhardt s 1853 observations of insoluble resin formation while dehydrating sodium salicylate [2]. These were followed by similar reports on the behavior of salicylic acid derivatives under a variety of reaction conditions by Schroder et al. (1869), Baeyer (1872), Velden (1877), Doebner (1896 and 1898), Speyer (1897) and Baekeland (1909-1912) [3-17]. Many of these early reports appear to involve the formation of phenolic polyesters rather than the phenol-aldehyde resins that we think of today. For... 

The constitution of quinine is not yet elucidated. Its relationship to quinoline has long been known, since it gives this substance on distillation with caustic potash (Gerhardt). 

Choosing to describe their rule in terms of a spread of a disease, Gerhardt and Schuster interpret a as follows. Cells whose value a = 0 are labeled as healthy cells cells with value a = N are labeled as ill cells cells with intermediate values 1 < a < N are called infected. The temporal evolution of the system, parameterized by constants p,/(, pj and u (see below), is then defined in terms of these three different infection states. 

As an example, consider a system of size 20 x 20, and take N = 100, px = 2 and Pj = 3. What happens if we vary the parameter u between the value 1 and, say, 20 Gerhardt and Schuster found that when this system evolves from a random initial state (using the Moore neighborhood for updates), some combination of four basic behavioral types emerges [gerh89]. Behavioral types - which appear to depend most strongly on the value of the parameter u - are characterized by both the manner in which the fraction of sites that are infected (= / ) varies as a function of time and the kind of transition-wave spatial patterns that develop ... 

Fig. 8.15 Screenshot from a run of Gerhardt and Schuster s Hodgepodge CA rule.

Gerhardt et al. [34] described three possible ways to prepare alkylphenol-polyglycol ether carboxylates, namely, the method with NaOH and SMCA, the method by oxidation by means of oxygen, and the method whereby the nonionic reacts with acrylonitrile followed by hydrolyses with hydrochloric acid. The synthesis with acrylonitrile forms in contrast to the other two methods, carboxyethylated compounds with the general formula... 

In comparison with other anionics, little has been published concerning methods of analysis of ether carboxylates. Gerhardt et al. [238] investigated the analytical determination of ether carboxylic acids in reaction mixtures obtained by reaction of nonylphenol ethoxylates with sodium chloroacetate as well as by cyanoethylation by different methods. Several methods, used for other surfactants as well [239], can be used for ether carboxylates. 

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