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Highly stable, pure, and anhydrous organometallic YBa2Cu3O7‐δ (YBCO) precursor solutions were prepared by dissolving commercial YBCO powder in acetone by trifluoroacetic anhydride (TFAA) or a mixture of TFAA with propionic acid for low fluorine precursors. It is shown that compared to conventional oil bath heating reported in literature, the reaction to produce YBCO precursor occurs 72 times faster by microwave heating. More importantly, the formation of byproducts is suppressed, as shown by nuclear magnetic resonance (NMR) and mass spectrometry (MS). This approach allows a highly reproducible preparation of superconducting coatings which is of interest for low‐cost manufacturing processes capable of large‐scale production of the coated conductors via chemical solution deposition (CSD). This technology requires reliable and stable precursor solutions for continuous deposition. In this work, we obtained YBCO thin films on single‐crystal substrates ((100)‐LaAlO3) with a high critical current density (Jc) of 3‐4 MA/cm² in self‐field at 77 K using TFA‐based YBCO precursors and Jc of 5‐6 MA/cm² using low fluorine YBCO precursors.

In this study the merits of polymerized imidazolium based ionic liquid (PIL) stationary phases obtained via condensation and free radical polymerizations are compared as stationary phases in gas chromatography (GC). Poly(1-vinyl-3-butyl-imidazolium - bis(trifluoromethane)sulfonamide) (poly(ViC4Im(+) NTf2(-))) was obtained via a chain-growth mechanism while poly(propylimidazolium-NTf2) (poly(C3Im(+) NTf2(-))) was synthesized via a step-growth polymerization. The thermal stability of both polymers was assessed using thermal gravimetric analysis and compared with bleeding profiles obtained from the statically coated GC columns (30m×0.25mm×0.25μm). The performance was compared to what could be obtained on commercially available 1,5-di(2,3-dimethylimidazolium)pentane(2+) 2NTf2(-) (SLB-IL111) ionic liquid based columns. It was observed that the step-growth polymer was more thermally stable, up to 325°C, while the chain-growth polymer showed initial degradation at 250°C. Both polymers allowed reaching minimal plate heights of 0.400-0.500mm for retained solutes such as benzaldehyde, acetophenone, 1-methylnaphthalene and aniline. Assessment of the McReynolds constants illustrated that the polarity of the step-growth polymer was similar to the SLB-IL111 column, while displaying improved column stability. The PIL phases and particularly the so far little studied condensation based polymer shows particular retention and satisfactory column performance for polar moieties such as esters, amine and carbonyl functionalities.

The applicability of the kinetic plot theory to temperature-programmed gas chromatography (GC) has been confirmed experimentally by measuring the efficiency of a temperature gradient separation of a simple test mixture on 15, 30, 60 and 120m long (coupled) columns. It has been shown that the temperature-dependent data needed for the kinetic plot calculation can be obtained from isothermal experiments at the significant temperature, a temperature that characterizes the entire gradient run. Furthermore, optimal flow rates have been calculated for various combinations of column length, diameter, and operating temperature (or significant temperature). The tabulated outcome of these calculations provide good starting points for the optimization of any GC separation.

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