Stage Sponging

Sponge and Dough System Conventional Breadmaking. Most domestically produced bread is manufactured by the two-mixing stage sponge and dough process (Fig. 1) (6,30—33). 

Figure 5. The final stages in the production of zirconium sponge (the Kroll process).

One of the most remarkable attributes of Pechini-type routines is the behaviour of precursor resins (gels) upon heating. On the first stage of thermal decomposition of samples, being dried at approx. 120°C, they decompose forming very porous and voluminous sponge-cake-like materials [6], Probably, just at this temperature, a highly porous intermediate is... 

The process is operated in heated, batch reactors under an inert atmosphere. Two companies (Deeside Titanium, North Wales, and New Metals Industries, Nihongi, Japan) operate a one-stage process. Reactive Metals Industries Company, Ashtabula, OH, operates a two-stage process in the first stage, at 230°C, the trichloride and dichloride are formed. In the second, more sodium is added and the temperature is raised to 1,000°C. The sponge product is mixed with sodium chloride, which is leached out with dilute hydrochloric acid. Based on the work by M. A. Hunter at Rensselaer Polytechnic, New York in 1910. See also Kroll. 

A reaction by Clough et al. comes close to the direct synthesis shown in Scheme 1 (89TL7469). Here amides (62) react in a radical mechanism to 4-methylene compounds (63) that with 03/PPh3 are converted to tetramic acids (64). (See Fig. 29.) Several authors, however, prepared esters of 4-amino-3-oxo-butanoic acid, which served as precursors for intramolecular cyclization to tetramic acids (82JHC883). Koehler and Gerlach in an initial stage of a synthesis of dysidine, contained in marine sponge... 

Uriz, M.J., Turon, X., Becerro, M.A., and Galera, J., Feeding deterrence in sponges. The role of toxicity, physical defenses, energetic contents, and life-history stage, J. Exp. Mar. Biol. Ecol., 205, 187, 1996. 

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