J. Planar Chromatogr. 5, 80-86 (1992). Forced-flow planar chromatographic (FFPC) techniques such as over-pressured layer chromatography (OPLC) and rotation planar chromatography (RPC) have been used to study the influence of the forced eluent flow on the dimensions of the spot. The correlation between the eluent flow and the transverse spot dimension on TLC and HPTLC layers has demonstrated that diffusion can be dramatically reduced up to certain eluent flow; at higher eluent flows diffusion remains constant or increases only slightly.

Proc. Intern. Symp. on Planar Separations, Planar Chromatography 2001, pp. 137-148. Presentation of the main steps for a systematic optimization of a planar chromatographic method according to the 'PRISMA' system: The first stage is the selection of the stationary phase, the vapor phase, and suitable solvents which can occasionally immediately result in a suitable separation. For most real separation problems the second stage, optimization of the mobile phase, is also necessary. The third part of method development is the selection of the final conditions, e.g. the mode of development, transfer of the mobile phase to an appropriate forced-flow method, and the selection of suitable operating parameters.

Chromatogr. 2, 287-289 (1985).(Chinese) (Application of the chord distance method to the selection of thin-layer chromatography and paper chromatography optimal combination.) Study on the cluster analysis by using weighted pair-group and shortest distance methods for TLC of 26 food dyes with 10 developing systems. Method optimization. The same study was made for paper chromatography of 14 amino acids with 5 developing system. The results showed advantages of the method.

Reinvestigation of the effects of solvent pH on Rf values. J. Chromatogr. 354, 99-106 (1986). Ion-pair reversed-phase TLC of 4 organic acids on silica, paraffin-impregnated silica, and on C 18-bonded silica with 4 ion-pair- reagents. Investigation of the effects of solvent pH on Rf values. Discussion of some possible explanation and the potential usefulness of the phenomenon. Rf values of the compounds were unaffected by solvent pH, when tetra-n-butylammonium iodide and tetra-heptylammonium bromide were used as ion-pair reagents, but significant dependence of Rf on the solvent pH was found when cetrimide and cetyltrimethylammonium bromide were used.

Chromatographia 25, 82-86 (1988). Determination of the lipophilicity of 33 nitrostyrene derivatives by reversed-phase TLC on three alkyl- bonded silicas with methanol. Discussion of the relationship between RM value of each compound and the concentration of the organic solvent, the retention strength and selec tivities of the three bonded phases, and the impact of the change of methanol concentration on the retention.

J. Chromatogr. Sci., 26, 325-330 (1988). Investigation of the chromatographic behavior of inorganic ions on Sephadex G-25 with acetone - water mixed eluent system in TLC and CC. Emphasis on the effects of eluent electrolyte and of the solvent compositions inside and outside the gel beads. Evaluation of the partition effect on the retention mechanism for different salts. Proposal of a theoretical model interpreting the effect of the background eluent ions on the capacity factors of the analyte ions.

Thin-layer chromatographic retentions on silica of some (E)- and (Z)-oxazolones and related cinnamates as a function of mobile phase effects or Hammett constants. J. Chromatogr. 545, 161-175 (1991). Study of the TLC behavior of 20 diastereoisomeric 1,1-disubstituted 2-arylethenes [(Z)- and (E)-oxazolones and - cinnamates] on silica with 40 mobile phases. Correlation and discussion of the relative retentions and the retentions themselves with solvent selectivity effects of Hammett constants of the various substituents on the aryl group.

2. Experimental condition affecting resolution and Rf value.) (Japanese). Kagaku to Kyoiku (Jap. J. Sci. & Educ.) 43 (3), 178-181 (1995). Demonstration of the effect of the experimental conditions, such as pre-saturation, developing distance, developing solvent system, and the stationary phase, on the degree of resolution and Rf value in TLC analysis.