The present work reports on the investigation of a mixed binary chiral stationary phase (CSP) prepared by simultaneous attachment of permethylated-bcyclodextrin (D selector) and resorcinarene with pendant L -or D-valine diamide groups (LV and DV selectors, respectively) to a polysiloxane matrix via platinum-catalyzed hydrosilylation. The gas-chromatographic investigation of a number of racemates on the four different CSPs (D, DV, DDV, and DLV) showed that the enantioselectivity of the individual chiral selectors was retained in the mixed binary CSPs. As a consequence, hydrocarbons, underivatized alcohols, ketones, and almost all proteinogenic amino acid derivatives could be separated simultaneously on each of the mixed CSPs. Matched and mismatched cases of enantioseparation on the mixed binary CSPs were observed but turned out to be of minor importance for enantiomeric separation. In general, more racemates were separated with a z 1.02 on the mixed phases as compared to the single phases. In order to analyze the influence of the presence of the diamide selector on the enantioselectivity of the cyclodextrin selector, a mixed ternary CSP containing the selector D and a racemic mixture of the selectors DV and LV [D(DVLV)] was prepared and investigated. Merits and limitations of the approach of mixed binary CSPs are discussed.

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We present a systematic evaluation of calixarene derivatives as high-resolution negative tone resists for electron-beam lithography with a focus on their sensitivities. We studied the effect of a modification of the calixarene molecules to trimethysilyl ethers as well as the effect of an introduction of an allyl group and showed that the introduction of double bonds into the molecules can improve the sensitivity of the resists while their position does not seem to be important. The high-resolution capability of tetraallylcalix[4]arene was confirmed by fabricating an 18 nm dot array.

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