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Detailed morphological and structural characterization of high-aspect-ratio polyaniline nanofibers obtained using a small amount of p-aminodiphenylamine (dimer) or p-phenylenediamine (diamine monomer) as an initiator into a rapidly mixed reaction is presented. Structural characteristics have been investigated by FT-IR, UV−vis−NIR, solid-state 13C NMR, and 15N NMR, while the morphology was examined using scanning electron microscopy (SEM) and transmission electron microscopy (TEM). Nanofibers obtained with the addition of an initiator appear longer and less entangled than those obtained without any initiators. TEM analysis revealed a distinct morphological difference between the nanofibers synthesized with different additives. The p-aminodiphenylamine-initiated polyaniline possesses an electrical conductivity of 3.0 S cm−1, while the p-phenylenediamine-initiated counterpart has a conductivity of 1.7 S cm−1. FT-IR, 1H−13C cross-polarization (CP), 15N direct polarization (DP), and UV−vis−NIR spectroscopy confirm that a regular polyaniline structure prevails in both nanofibers. Therefore, various initiators only result in a slight difference in the final polymer molecular structure and physical properties, but such minor divergence dictates the subsequent chain assembly and affects the supramolecular morphology significantly.

Three‐dimensional (3D) printing brings exciting prospects to the realm of conjugated polymers (CPs) and organic electronics through vastly enhanced design flexibility, structural complexity, and environmental sustainability. However, the use of 3D printing for CPs is still in its infancy and remains full of challenges. In this review, we highlight recent studies that demonstrate proof‐of‐concept strategies to mitigate some of these problems. Two general additive manufacturing approaches are featured: direct ink writing and vat photopolymerization. We conclude with an outlook for this thriving field of research and draw attention to the new possibilities that 3D printing can bring to CPs. © 2019 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2019, 57, 1592–1605

Suction had no significant clinical effects on the macular thickness and retinal nerve fiber layer during femtosecond lenticule extraction or femtosecond laser-assisted LASIK.

Quinacridone diimines 1-10 were synthesized by the condensation of anilines with alkyl substituted quinacridones (QA). Photophysical and electrochemical properties of the compounds were investigated. Unconventional behavior of absorption spectra suggested a decrease in p _ conjugation within the QA skeleton as well as lack of extended p _ conjugation between the QA skeleton and the N-phenyl rings. A computational study of compounds 1-10, a variable temperature 1 H NMR study of compounds 2, 7 and 10 (for instance), and single crystal X-ray analysis of 2, 3, 6, 7, 8 and 10 indicated that the anomalous behavior is due to the buckled, non-planar structure of the quinacridones. Moreover the molecules existed in two interconvertible geometric isomeric forms at different temperatures. Molecular orbital calculations were performed at B3LYP/6-31+G(d), B3PW91/6-31G(d) and PBEPBE/6-31G(d) levels of theory at B3PW91/6-31G(d) optimized structures for both isomers of all compounds (1-10); the results obtained are in close agreement with the experimentally determined values.

This study evaluated the performance of plusoptiX A12C in detecting amblyopia risk factors (ARFs) in Chinese children aged 3-to-4-year. PlusoptiX examination was successfully conducted among 1,766 subjects without cycloplegia to detect refractive error, asymmetry and media opacity. Cycloplegic retinoscopy (CR) was conducted on 357 children suspected of having vision abnormalities. Statistical differences between CR and the device were confirmed using the mean spherical value (+1.41 ± 0.87 D versus +1.14 ± 0.81 D), cylindrical value (−0.47 ± 0.64 versus −0.84 ± 0.78) and spherical equivalent (SE) value (+1.17 ± 0.84 D versus +0.72 ± 0.64 D) (all P < 0.0001). In the emmetropia group, the differences were statistically significant for the cylinder and SE (all P < 0.0001) but not the sphere (P = 0.33). In the hyperopia group, the differences were statistically significant for the sphere, cylinder and SE (all P < 0.0001). For refractive and strabismic ARFs detection, the sensitivity, specificity, positive predictive value, and negative predictive value were calculated, respectively.

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