Micro-mixing

To help understand what occurs, imagine that we have A and B available, each first as a microfluid, and then as a macrofluid. In one beaker mix micro A with micro B, and in another beaker mix macro A with macro B and let them react. What do we find Micro A and B behave in the expected manner, and reaction occurs. However, on mixing the macrofluids no reaction takes place because molecules of A cannot contact molecules of B. These two situations are illustrated in Fig. 16.4. So much for the treatment of the two extremes in behavior. 

M 12] [P 11] To analyze the effect of the number of holes and their positions on the acoustic mixing, three artificial mixing micro chambers were proposed, the first with one bubble pocket in the center (a), the second with four bubble pockets at the corners and the third with five air pockets with four at the comers and one in the center [23]. It was found that acoustic mixing depends largely on the number of holes and their positions (see Figure 1.30). 

Tohnson, T.J., Ross, D., Gaitan, M., Locascio, L.E., Laser modification on channels to reduce band broadening or to increase mixing. Micro Total Analysis Systems, Proceedings 5th iTAS Symposium, Monterey, CA, Oct. 21-25, 2001, 603-604. 

In stirring, distinction is made between micro- and macro-mixing. Micro-mixing concerns the state of flow in the tiniest eddies. It is determined by the kinematic viscosity, v, of the liquid and by the dissipated power per unit of mass, = P/pV. Correspondingly, the so-called Kolmogorov s micro-scale k. of the turbulence is laid down as being k = (v3/e)1 4. (By the way, this equation is clearly derived from dimensional analysis )... 

Micro-Mixing Micro-mixing is the smallest scale of mixing. In terms of dimensions, it is at or below the Kolmogoroff microscale that can be calculated by Equation (9.9). Micro-... 

In the course of pursuing the hands of the silk, the combinations and fusions of multiplied technologies have been advanced in various fashions. For instance, one of the technical skills to minimize an internal stress between warp and weft caused by an effect of a spontaneous extention through crystallization process, the skill to mix micro denier yarns, and the skill to give a concave and convex in a sub-micron order for a control on surface touch is turned in. Regarding the cross section of fibers,a lot of kinds of configurations have been developed other than a trilobal cross section. 

As inoculum, unadapted mixed micro-organisms are used, e.g. from a municipal activated sludge plant at a concentration of 30 mg/1 dry solids... 

Figure 14.1 Generic reactor configurations for homogeneous liquid-phase reactions comprising micromixers (MIX), micro heat exchangers (HEX) and microreactors (REAC) in integrated (int) or connected (con) fashion. Reprinted with permission from Chemistry Today [10].

Macro- and Micro-Mixing in Reactors Models Explicitly Accounting for Mixing Micro-Probability Density Function Methods... 

Atasoglu, C., A.Y. Guliye and R.J. Wallace, 2004. Use of stable isotopes to measure de novo synthesis and turnover of amino acid-C and -N in mixed micro-organisms from the sheep rumen in vitro. Brit. J. Nutr. 91, 253-261. 

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