The IGNITOR Load Assembly Structural Analysis and Toroidal Field Coil
The structural analysis of the IGNITOR machine load assembly has been performed taking into account the friction coefficients at the interfaces between the significant components. The finite element ANSYS model was used to analyze the nonlinear mechanical behavior of the structure. The calculation shows stresses within the allowable limits at the operating temperature. Interlaminar shear stresses values on TFC insulation have been validated by the results of test performed by Ansaldo. Two full size of Ignitor TFC turns have been manufactured by Kabel Metal to qualify the fabrication process and the hardening of the material OFHC. Several samples of the cooling channel were machined to validate the Electron Beam (EB) welding process
Optimization of the IGNITOR operating scenario at 11 MA
Abstract Several endeavours have been made, in the frame of the IGNITOR design, in order to minimize technological problems, reducing electromagnetic loads, power supply requirements while avoiding the use of not completely proven materials. The present design modifications comprise both the operating scenario for the poloidal field (PF) currents and the PF coils geometry. The new scenario and a relevant simulation of a related typical fast vertical disruption, in the most dangerous plasma conditions in IGNITOR, have been simulated with the MAXFEA code. In order to reduce the EM loads on plasma chamber and the related stresses due to plasma disruptions, a new approach has been investigated based on the possibility of mitigating these loads by using copper toroidal layers added to the plasma chamber in proper positions. We found that this expedient could be quite effective not only in increasing the time constant of the plasma displacement but even in reducing the vertical force and its combined effect with hoop force on the vessel during a vertical displacement event (VDE).
l-Phenylalanine dehydrogenase from Brevibacterium sp. for production of l-phenylalanine by reductive amination of phenylpyruvate
SummaryFor production of l-phenylalanine the reductive amination of phenylpyruvate, catalyzed by phenylalanine-dehydrogenase was examined. To reach high levels and a sufficient stability of the inducible intracellular enzyme, growth conditions of Brevibacterium sp. are optimized. For continuous production of l-phenylalanine in an enzyme membrane reactor, the kinetic parameters of the partially purified enzyme are determined.In continuous production a space time yield of 37.4 g l-Phe l-1 d-1 can be reached.By means of the measured kinetic parameters and simultaneous calculation of the mass balances of all reaction components the behaviour of the reactor can be simulated. For certain conditions the multi-enzyme-system shows multiple steady-states.