Simulated supernatant

Most of the supernatant was sent back to the reactor, in order to simulate the operation of a 1000 L reactor working at a 1 d perfusion rate. Rotor with a non-conventional design, containing 4 layers of spiral settling zones. 

For each experiment, the supernatant was placed in 15-mL conical tubes, and the pH was adjusted with either 1 N KOH or 1N HN03. The pH of the supernatant after the bioreactor run was 7.0. Simulated potato effluent (SPE) medium was used as a surfactin-free control and the pH adjusted likewise. SPE contained the following per liter of nanopure water 5 g of potato starch, 3.5 g of peptone, 3.5 g of tryptone, 0.2 g of MgS04-7H20,0.1 g of yeast extract, and 0.8 g of (NH4)2S04. 

Fig. 29. Origin of systematic errors in spite of potentially error-free analysis. On-line sampling setups (top) and time trajectories of limiting substrate concentration during sample preparation in the two paradigmatic setups depending on the actual culture density (bottom). Either a filter in bypass loop is used for the preparation of cell-free supernatant (upper part in top insert) or an aliquot of the entire culture is removed using an automatic sampler valve and a sample bus for further inactivation and transport of the samples taken (lower part). Both methods require some finite time for sample transportation from the reactor outlet (at z = 0) to the location where separation of cells from supernatant or inactivation by adding appropriate inactivators (at z = L) takes place. During transport from z = 0 to z = L, the cells do not stop consuming substrate. A low substrate concentration in the reactor (namely s KS) and a maximal specific substrate consumption rate of 3 g g h 1 were assumed in the simulation example to reflect the situation of either a fed-batch or a continuous culture of an industrially relevant organism such as yeast. The actual culture density (in g 1 1) marks some trajectories in the mesh plot. Note that the time scale is in seconds...

The stabihzation of a range of contaminants, including Cr , in Ceramicrete was demonstrated by Wagh et al. [60] with two liquid waste streams that simulated radioactive supernatant and sludge from Hanford tanks within the DOE complex. These waste streams... 

Leaching of contaminants Eission products Tc, partitioned from high-level waste tanks, debris from contaminated pipes from K-25 plant at Oak Ridge Cs, from salt supernatant and sludge, silico-titanates, and wastewater Radioactive components Ra, Fernald silo waste, transuranics, simulated and actual Rocky Flats ash waste, wastewater... 

Leaching of salts Simulated salt waste streams (both supernatant and sludge)... 

The apparatus may be used for a batch sedimentation by sinq>ly setthng for prescribed periods of time and sanq)ling at all the san le points. An arithmetic average concentration is confuted for all the points above and including the one in question. In this way decantation of supernatant liquid above that point is simulated. 

Pauli has often used the supernatant of an elcctrodecantation as the intermicellar liquid I his procedure is certainly not permissible, because in electrodecantation not only the sol particles but also the ions are decanted thus simulating an intermicellar liquid which is too dilute ... 

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