The unusual molecular complexation of the enantiomers of aspartic acid in water was discovered and proven by a solubility test, solution freezing point, crystallization kinetics, and the incubation time change. The transformation of a "conglomerate solution" (CS) to a "racemic compound solution" (RCS) was dependent on both temperature and time. The CS was the solution phase which produced conglomerate crystals, and the RCS was the solution phase which gave a racemic compound. Fourier transformed infrared spectroscopy and powder X-ray diffraction were used to characterize aspartic acid solids crystallized from those complex solution phases and to distinguish conglomerate crystals from a racemic compound. We found that it took more than 36 h at 25 °C and 5 h at 45 °C just to complete the solution phase transformation of the CS of aspartic acid to the RCS of aspartic acid. However, the presence of an equimolar of succinic acid could hinder the solution phase transformation of the CS of aspartic acid to the RCS of aspartic acid for up to at least 8 h at 60 °C. This leeway of hours had provided an opportunity for the thermodynamically stable racemic aspartic acid to convert into the metastable conglomerate in water first by either a rapid acid-base reaction or the addition of an antisolvent with the temperature drop, without being concerned by its back conversion later to a racemic compound thermodynamically for quite some time. As a result, enantioseparation of aspartic acid by preferential crystallization in a large scale would have been very common and easy to occur on the primitive earth.

All experimental procedures discussed could be treated as a screening tool for probing the existence of molecular association among the chiral molecules and the solvent system. The molecular association phases of a racemic conglomerate solution (CS) and a racemic compound solution (RCS), and the templating effect of aspartic acid solid surface were observed to minimize the chance of redissolving racemic conglomerate and racemic compound aspartic acid in water and reforming an RCS in crossovers experiments. Only 1 %wt% of l-aspartic acid was adequate enough to induce a transformation from a racemic compound aspartic acid to a racemic conglomerate aspartic acid. This would make the propagation of biochirality more feasible and sound. However, tetrapeptide, (l-aspartic acid)4 , failed to induce enantioseparation as templates purely by crystallization. Nonclassical crystallization theory was needed to take into account the existence of a CS. Fundamental parameters of the crystallization kinetics such as the induction time, interfacial energy, Gibbs energetic barrier, nucleation rate, and critical size of stable nuclei of: (i) racemic compound aspartic acid, (ii) racemic compound aspartic acid seeded with 1 %wt% l-aspartic acid, (iii) racemic conglomerate aspartic acid, and (iv) l-aspartic acid were evaluated and compared with different initial supersaturation ratios. Morphological studies of crystals grown from the crystallization kinetics were also carried out.

The influence of the spacing of the partially porous aerostatic journal bearings and the rotating speed of the spindle on the pressure distribution in the bearing gap and the housing gap were studied. Based on the finite volume method and the pressure-velocity coupling scheme of the SIMPLE algorithm with the standard k-ε turbulent model, A CFD software was used to solve the Navier-Stokes equations to figure out the pressure in the bearing gap and the housing gap. The computed results indicated that when the spacing of the bearings between air outlets was increased, the pressure got higher not only in the bearing gap, but also in the housing gap. The load carrying capacity of the bearings and the stiffness of the spindle could be improved. If the spacing of bearings was reduced by adding one more bearing to the location between the original bearings, the pressure in the narrower housing gap would decrease, while that in the wider housing gap would increase. Though the extra bearing could not help increase the net pressure exerted on the spindle effectively, it did help redistribute the housing gap pressure so that the pressure difference in the air gap could be reduced and the spindle was able to rotate stably.