Charge neutral, nonconjugated organic radicals have emerged as extremely useful active materials for solid-state electronic applications. This previous achievement confirmed the potential of radical-based macromolecules in organic electronic devices; however, charge transport in radical molecules has not been studied in great detail from a fundamental perspective. Here we demonstrate the charge transport in a nonconjugated organic small radical, 4-hydroxy-2,2,6,6-tetramethylpiperidin-1-oxyl (h-TEMPO). The chemical component of this radical molecule allows us to form a single crystal via physical vapor deposition (PVD). While the charge transport of this macroscopic open-shell single crystal is rather low, thermal annealing of the well-defined single crystal enables the molecule to have a rapid charge transfer reaction due to the electronic communication of open-shell sites with each other, which results in electrical conductivities greater than 0.05 S m–1. This effort demonstrates a drastically different model than the commonly accepted conjugated polymers or molecules for the creation of next-generation conductors.

The transmittance in fringe-field switching liquid crystal (LC) displays, which show a wide viewing angle, is dependent on the position along the electrode position. The reason for this is that the dielectric torque (and hence the twist angle) varies with position. This effect depends on the type of LC: a display using an LC with positive dielectric anisotropy has less transmittance than one with negative dielectric anisotropy. Furthermore, the transmittance decreases with decreasing cell gap. The difference between the LC types can be reduced and the transmittance can be improved greatly even for a low cell gap by optimizing the electrode structure to enhance the region of in-plane twist.

The aim of this investigation was to find a proper harvesting period and establishing fern number, which effects the spear yield, bioactive compounds and antioxidant activities of Asparagus officinalis L. Spears were harvested at 2, 4, and 6 weeks after sprouting. Control for comparison was used without harvest. Spears and total yield increased with prolonged spear harvest period. In harvest of 6 weeks long optimum spear yield was the highest and fern numbers were 5 ~ 8. Bioactive compounds (polyphenols, flavonoids, flavanols, tannins and ascorbic acid) and the levels of antioxidant activities by ferric-reducing/antioxidant power (FRAP) and cupric reducing antioxidant capacity (CUPRAC) assays in asparagus ethanol extracts significantly differed in the investigated samples and were the highest at 6 weeks harvest period (P < 0.05). The first and the second segments from the tip significantly increased with the increase of catalase (CAT). It was interesting to investigate in vitro how human serum albumin (HSA) interacts with polyphenols extracted from investigated vegetables. Therefore the functional properties of asparagus were studied by the interaction of polyphenol ethanol extracts with HSA, using 3D- FL. In conclusion, antioxidant status (bioactive compounds, binding and antioxidant activities) improved with the harvesting period and the first segment from spear tip. Appropriate harvesting is effective for higher asparagus yield and its bioactivity.

Organic mixed ionic and electronic conductors typically have heterogeneous conjugated macromolecular backbones and ether-based pendant groups to transport ions and charges. Moving from this archetype toward one with a single component, nonconjugated redox-active radical polymers that conduct both the charge and mass have significant benefits, such as they can be readily synthesized in large quantities and have the ability to produce either hole-or electrontransporting radical polymers by the selective tuning of the pedant group chemistry. Here, we demonstrate long-range (i.e., for lengths >50 μm) operational mixed ionic and electronic conduction in an amorphous, nonconjugated, low-glass-transitiontemperature organic radical polymer upon blending the macromolecule with an ionic dopant lithium bis(trifluoromethanesulfonyl)imide salt (LiTFSI). Tuning the precise chemical nature of the functional radical pedant group using this ionic dopant is of key importance for the enhancement of long-range electrical conductivity. Moreover, the maximum ionic conductivity was 10 −3 S cm −1 at elevated temperatures, and this was the highest reported value for a radical polymer-based system. Our findings demonstrate a significantly different macromolecular design paradigm than the commonly accepted heterogeneous composition for the creation of next-generation organic mixed ionic and electronic conductors.

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