The length scale for this diffusional process is determined by the size of the smallest eddies formed and is referred to as the Kolmogorov length scale. Along with time

and kinetic energy scales, each determined by these local flow conditions alone, (i.e., related to kinematic viscosity and the energy dissipation rate per unit mass), the so called Kolmogorov scales are established. Estimating the magnitude of these Kolmogorov parameters can be accomplished with reasonable confidence using proven theoretical turbulence calculations. #selleck chemicals keyword# The significance is that the length scale over which no further mixing takes place is established and molecular diffusion now dictates timing for the necessary steps involved in the homogeneous nucleation and growth processes. Inhibitors,research,lifescience,medical These mixing subprocesses generally occur in series, but often to some extent, in parallel. Turbulent energy dissipation rates, for example in modified impinging jet technologies [11, 12, 27–29], are estimated to be on the order 107W/kg and higher when using these micromixing models. At these levels, rapid micromixing and mesomixing (on time scales of 4 and 20μs, resp.)

are achieved, and the length scale of the smallest eddies are at the nanoscale. Note that residence times in many of the microreactors systems Inhibitors,research,lifescience,medical used for PI applications [30], particularly those utilizing impinging jets, are of the order 1ms and lower. Incorporating these fundamental principles and using appropriately designed equipment it is possible to precisely control each step in the crystallization process. Mixing at the nanometer scale Inhibitors,research,lifescience,medical provides a uniform supersaturation ratio. The onset of the nucleation process can be manipulated Inhibitors,research,lifescience,medical by controlling the timing and location of the mixing of the solvent and antisolvent streams that

are used to generate the supersaturated state. This in combination with an evenly dispersed homogeneous supersaturation ratio results in uniform crystal growth and stabilization rates. 2.1.5. Creating Nanoscale Entities The generation of nanoscale homogeneous regions dispersed throughout the system is a major requirement for the success of this bottom-up process. When accomplished, it is reasonable to consider STK38 these regions as nanoreactors. This concept is ideal for our purposes since both length and time scales are quite small for the processes involved in creating these monodispersed nanoparticles. Consequently, it is immaterial whether or not these regions are stabilized, as for example, by use of surface active agents. It is important to reiterate that the length scale over which no further mixing takes place is established and molecular diffusion now dictates timing for the necessary steps involved in the homogeneous nucleation and growth processes.