Optimization and parameter study for chiral separation by capillary electrophoresis

Orthogonal design and uniform design were used for the optimization of separation of enantiomers using 2,6-di-O-methyl-beta-cyclodextrin (DM-beta-CD) as a chiral selector by capillary zone electrophoresis, The concentration of DM-beta-CD, buffer pH, running voltage, and capillary temperature were selected as variable parameters, their different effects on peak resolution were studied by the design methods. It was concluded that orthogonal design offers a rapid and efficient means for testing the importance of individual parameters and for determining the optimum operating conditions. However, for a large number of both factors and levels, uniform design is more efficient, The effect of addition of methanol and citric acid buffer on the separation of enantiomers was also examined.

New cocktail functional monomers in making molecule imprinting polymer with high chiral selectivity

in order td produce molecule imprinting polymer (MIP) with high chiral selectivity against N-c-protected amino acid, new cocktail functional monomers acrylamide (AM) + 2-vinylpyridine (2-VP) and AM + methacrylic acid (MAA) were investigated. AM + 2-VP was found to be more efficient in improving the selectivity and resolution of the molecule imprinting polymer.

Curved Inertia Frames: Visual Attention and Perceptual Organization Using Convexity and Symmetry

In this paper we present an approach to perceptual organization and attention based on Curved Inertia Frames (C.I.F.), a novel definition of "curved axis of inertia'' tolerant to noisy and spurious data. The definition is useful because it can find frames that correspond to large, smooth, convex, symmetric and central parts. It is novel because it is global and can detect curved axes. We discuss briefly the relation to human perception, the recognition of non-rigid objects, shape description, and extensions to finding "features", inside/outside relations, and long- smooth ridges in arbitrary surfaces.

Synthetic studies on optically active Schiff-base ligands derived from condensation of 2-hydroxyacetophenone and chiral diamines

Three optically active Schiff-base ligands have been prepared by condensation of 2-hydroxyacetophenone with (IR,2R)-(-)-1,2-diaminocyclohexane, (1S,2S)-(-)1,2-diphenylethylenediamine or R-(+)-2,2'-diamino-1,1'-binaphthalene, respectively. The products have been characterized by their IR, H-1- and C-13-NMR spectra.