High precision near-infrared spectroscopy in the wavelength region 1100-1800 nm was used to provide data on the intermolecular interactions of alcohols and water. This data can be used to further refine alcohol/water composition diagrams as an aid to understanding gradient elution in reversedphase chromatography using an alcohol/water mixture as a mobile-phase system. The spectral data were analyzed using multivariate model-based regression. Within the approximation of the ideal associated solution model, a lower limit on the number of alcohol/water complexes was determined. Additionally, the spectra, stoichiometry, and equilibrium constants governing the interrelationships of the pure species and their complexes were obtained. The spectroscopic data were consistent with four species in the alcohol/water composition diagrams. While a 1:1 alcohol/water complex is observed at high alcohol concentrations, a complex involving a higher number of waters becomes important at low alcohol concentration. This latter species may explain the unusual elution behavior patterns obtained when using low alcohol concentrations in reversed-phase chromatography.

The implementation of direct standardization (DS), piecewise direct standardization (PDS), and double-window piecewise direct standardization (DWPDS) instrumental transfer techniques for high-resolution (1)H NMR spectral data was explored. The ability to transfer a multivariate calibration model developed for a "master or target" NMR instrument configuration to seven different ("secondary") NMR instrument configurations was measured. Partial least-squares (PLS) calibration of glucose, glycine, and citrate metabolite relative concentrations in model mixtures following mapping of the secondary instrumental configurations using DS, PDS, or DWPDS instrumental transfer allowed the performance of the different transfer methods to be assessed. Results from these studies suggest that DS and PDS transfer techniques produce similar improvements in the error of prediction compared to each other and provide a significant improvement over standard spectral preprocessing techniques including reference deconvolution and spectral binning. The DS instrumental transfer method produced the largest percent improvement in the predictions of concentrations for these model mixtures but, in general, required that additional transfer calibration standards be used. Limitations of the different instrumental transfer methods with respect to sample subset selection are also discussed.

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Vapor‐deposited hexanitroazobenzene (HNAB) films were observed to form a dense amorphous structure that crystallizes to a mixture of the HNAB‐II polymorph and an unidentified structure over a period ranging from hours to weeks depending on the ambient temperature. Films crystallized at various temperatures were characterized using scanning electron microscopy, atomic force microscopy, X‐ray diffraction, and Raman spectroscopy to measure the impact of crystallization temperature on resultant microstructure. Crystallization temperature was observed to have different effects on film microstructure over two temperature regimes. At temperatures below approximately 65 °C, increases in temperature led to a greater fraction of the film forming the HNAB‐II polymorph and caused subtle changes in morphology. However, at higher temperatures, a thin surface layer was observed to form prior to crystallization, which led to films composed primarily of the unknown crystal structure with conspicuous differences in morphology.

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