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The design of plants or unit operations requires the knowledge of data for multicomponent systems. An approach is presented for the regression of binary interaction parameters required for the calculation of activity coefficients. Binary vapor pressure data are used to correlate these parameters for calculation of vapour/liquid equilibrium data. The advantage of the approach is the fact that only easily measured vapor pressure data are required. The procedure is demonstrated by means of two binary mixtures. Parameter regression, prediction of vapour/liquid equilibrium data as well as their experimental verification are demonstrated.

Microporous carbon foams were synthesized as structured catalyst supports by the carbide‐derived carbon (CDC) method. The self‐supporting foams showed a narrow pore size distribution which seems to induce shape‐selective effects during reactions. The applicability of these materials as supports for active metals was tested in a hydrogenation reaction of different olefins with a CDC powder wet impregnated with platinum.

Vorgestellt wird ein Verfahren, das aus wenigen Dampfdruckkurven binärer Gemische bei verschiedenen Zusammensetzungen die Wechselwirkungsparameter für die Berechnung von Aktivitätskoeffizienten zugänglich macht und so die Vorhersage von DampfFlüssigGleichgewichten ermöglicht. Der Vorteil dieses Verfahrens liegt in der experimentell einfachen Zugänglichkeit von Dampfdruckdaten. Eine Demonstration dieses Verfahrens erfolgt anhand zweier binärer Gemische, für die aus Dampfdruckdaten die entsprechenden DampfFlüssigGleichgewichte vorhergesagt und mit experimentell ermittelten Daten verglichen werden.

The Syk family tyrosine kinases play a crucial role in antigen receptor-mediated signal transduction, but their regulation and cellular targets remain incompletely defined. Following receptor engagement, phosphorylation of tyrosine residues within ZAP-70 and Syk is thought to control both kinase activity and recruitment of modulatory factors. We report here the characterization of novel mutants of ZAP-70 and Syk, in which conserved C-terminal tyrosine residues have been replaced by phenylalanines (ZAP YF-C, Syk YF-C). Both mutant kinases display a prominent gain-of-function phenotype in Jurkat T cells, as demonstrated by lymphokine promoter activation, tyrosine phosphorylation of potential targets in vivo, and elevated intracellular calcium mobilization. While the presence of p56-Lck was required for ZAP YF-C-induced signaling, Syk YF-C showed enhanced functional activity in Lck-deficient JCaM1 Jurkat cells. Our results implicate the C terminus of Syk family kinases as an important regulatory region modulating T cell activation.