Steady state growth

Chemostat A bioreaetor in whieh steady-state growth of miero-organisms is maintained over prolonged periods of time under sterile eonditions by providing the eells with eonstant input of nutrients and eontinuously removing effluent with eells as output. 

The multi-stream multi-stage system is a valuable means for obtaining steady-state growth when, in a simple chemostat, the steady-state is unstable eg when the growth-limiting substrate is also a growth inhibitor. This system can also be used to achieve stable conditions with maximum growth rate, an achievement that is impossible in a simple chemostat (substrate-limited continuous culture). 

A bacterium was grown as a glucose-limited chemostat culture and steady state growth yield (Yx/J was measured at different dilution rates. 

Finally, we were led to the last stage of research where we treated the crystallization from the melt in multiple chain systems [22-24]. In most cases, we considered relatively short chains made of 100 beads they were designed to be mobile and slightly stiff to accelerate crystallization. We could then observe the steady-state growth of chain-folded lamellae, and we discussed the growth rate vs. crystallization temperature. We also examined the molecular trajectories at the growth front. In addition, we also studied the spontaneous formation of fiber structures from an oriented amorphous state [25]. In this chapter of the book, we review our researches, which have been performed over the last seven years. We want to emphasize the potential power of the molecular simulation in the studies of polymer crystallization. 

For limiting nutrients, cellular concentrations are constant under conditions of steady-state growth. To ensure that the limiting nutrient is not diluted in the microbial population, kmt must be greater than the maximal growth rate, /imax. This limiting condition sets a minimum for the value of the Monod constant, Kmd = / max /[7]- Note that while Monod kinetics are more applicable than first-order kinetics for many ecological uptake processes, solutions of the above equations require considerably more a priori information [48]. 

By means of our experimental method (twin+single crystal kinetics) steady state growth morphology can be predicted as a function of supersaturation and temperature. 

Equation 37 describes the relationship between the rate of change of the crystal radius at the trijunction and the deviation of the local angle from the equilibrium value < >o. In this expression, < )(t) is the dynamic angle formed between the local tangents to the melt-ambient and crystal-ambient surfaces, and Vg(T) is the dimensionless pull rate of the crystal. For steady-state growth, equation 37 simply sets the angle with what must be a solid cylinder of constant radius. The importance of the dynamical form equation 37 is brought out in the next section. 

Numerical simulations that combine the details of the thermal-capillary models described previously with the calculation of convection in the melt should be able to predict heat transfer in the CZ system. Sackinger et al. (175) have added the calculation of steady-state, axisymmetric convection in the melt to the thermal-capillary model for quasi steady-state growth of a long cylindrical crystal. The calculations include melt motion driven by buoyancy, surface tension, and crucible and crystal rotation. Figure 24 shows sample calculations for growth of a 3-in. (7.6-cm)-diameter silicon crystal as a function of the depth of the melt in the crucible. 

A.T. Fromhold, N. Sato. Quasy-steady-state growth of layered two-phase oxides on pure metals // Oxid.Metals.-1981.- V.16, No.3/4.- P.203-220. 

The cold period of 1985-1993 and the subsequent steady-state growth in SST were accompanied by important changes in the Black Sea ecosystem. For example, the cold winters of 1985 and 1987 seem to oppose the mass development of the ctenophore Mnemiopsis leidyi, which invaded into the Black Sea in 1982-1983 [17]. A sharp decrease in its biomass that followed its mass... 

Olson, R. J., Soo-Hoo, J. B., and Kiefer, D. A. (1980). Steady-state growth of the marine diatom Thalassiosira pseudonana Uncoupled kinetics of nitrate uptake and nitrite production. Plant Physiol. 66, 383-389. 

Patermarakis, G., Chandrinos, J., and Masavetas, K. 2007. Formulation of a holistic model for the kinetics of steady state growth of porous anodic alumina films. Journal of Solid State Electrochemistry 11, 1191-1204. 

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