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Isobutene is the only product of the uncatalyzed dehydration of tert-butanol in sub-and supercritical water. There is a strong dependence of the conversion on the dissociation constant and the density of water. The following uncatalyzed oxidation of the in situ formed isobutene leads to isobutyraldehyde as the main product. The reaction was examined at temperatures of 350 ± 420 C and at pressures of 25 ± 35 MPa. Isobutyraldehyde can be formed with a selectivity of 50 % relating to tert-butanol (conversion 80 %) at 420 C and 35 MPa. 290* Similarity of Drag Reduction Phenomenon in the Both Polymers and Surfactant Systems Solutions L u b o m i r a B r o n i a r z -P r e s s J a c e k R o z a n s k i I z a b e l a P o l t o r a kIn this paper a number of flow experiments in straight tubes with aqueous polymer and soap solutions are described. The magnitude of the drag reduction by high molecular polymers decreases rapidly due to the mechanical and thermal degradations of the polymer. This drawback limits the application of polymer solutions in industry. The structure of the solutions of drag reducing surfactants is fully reversible. Drag reduction by dilute polymer solutions in turbulent pipe flow appears bounded between two universal asymptotes: the Prandtl ± Karman law for Newtonian turbulent flow and the maximum drag reduction asymptote. The experimental data showed that for surfactant solutions the drag reduction asymptote could be the line of laminar flow friction factor.It is shown, that the structure of macromolecular coil, characterized by its fractal dimension D, is a determinative in definition of modes of synthesis polyhydroxyether. Compact coil does not allow courses of reaction and this condition determines the first mode ± the formation of resinous products. The decrease of D determines a possibility of course of polycondensation reaction in the diluted solutions, and courses of reaction at a stage of gelation need still smaller value D, determining the value of fractal dimension for a ªdenseº solution. In a considered case the value D is regulated by the change of the polymer ± solvent interactions.Es wurde gezeigt, dass die Struktur des Makromolekularkna È uls, die als fraktale Gro È sse D charakterisiert wird, entscheidender Faktor ist fu È r die Bestimmung des Verlaufs der Synthese des Polyhydrooxia È thers. Der Kompaktna È ul erlaubt den Verlauf der Reaktion nicht und diese Bedinnung bestimmt das erste Regime ± die Bildung der harzartigen Produkte. Die Verrigerung der Gro È sse D bestimmt die Mo È glichkeit des Verlaufes der Reaktion der Polykondensation in den verdu È nnten Lo È sungen, aber fu È r den Verlauf der Reaktion im Stadium der Gelbildung ist die kleinere Gro È sse D erforderlich, die den Wert der fraktalen Gro È sse fu È r die ªdichteº Lo È sung feststellt. Im angegebenen Fall la È sst die Gro È sse D durch die Anderung der Wechselwirkung von Polymer ± Lo È sung regulieren.This paper addresses two important design implications for the esterification of acetic acid with ethanol in a cont...