Highlights d A comprehensive model is presented of the yeast nuclear pore complex (NPC) d Connectors link together different structural and functional layers in the NPC d Multiple structural and functional NPC isoforms co-exist in each cell d Modular construction allows structural plasticity and inner ring dilation of the NPC

Generally, residual solvent is embedded in perovskite precursor films fabricated from the Lewis adduct method. Most of the research focus on the ligand function of the solvent in forming a solvate complex for fabricating high quality perovskite films. However, little attention has been paid to the latent function of the solvent in the perovskite precursor films during the annealing process due to its fast extravasation at high temperature. Here, we develop a sandwich configuration of substrate/perovskite precursor films/PC61BM to retard the extravasation of solvent during annealing. We find that the restrained solvent induces an obvious solvent-mediated dissolution–recrystallization process, leading to high quality perovskite films with large columnar grains. There is mass transportation from small grains to large grains in the dissolution–recrystallization process, which follows the Ostwald ripening model. Inverted planar solar cells are fabricated on the basis of this annealing method. The photovoltaic performance of the solar cells is improved significantly due to its high quality perovskite films with large columnar grains.

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The Lewis acid-base reaction between PbI and solvent molecules is popular in fabricating PbI films by a two-step method for making perovskite solar cells. Here, we control the microstructure of PbI films through modulating the Lewis acid-base reaction by adding a small amount of N-methyl pyrrolidone into PbI/DMF solution. PbI films with excellent crystallinity and full coverage are fabricated by spin-coating the mixed solution on the substrate, which leads to high quality perovskite layers with low recombination rate and high efficiency for carrier transfer. As a result, the power conversion efficiency of the best perovskite solar cells increases from 13.3% to 17.5%.

In situ observations of the domain evolution and the polarization rotation under bipolar cyclic and static electric fields are carried out for ͓001͔-oriented 68Pb͑Mg 1/3 Nb 2/3 ͒O 3 -32PbTiO 3 ͑PMN-32PT͒ single crystal which is located at the morphotropic phase boundary ͑MPB͒. The results demonstrate that after being poled in ͓001͔ direction, the original rhombohedral ͑R͒ phase is transformed into a monoclinic M C phase with Pm space group. When the single crystal is subjected to bipolar cyclic electric field, distinct domain-boundary structures are revealed which are unlikely to be detected in static electric loadings. The existence of R phase is also detected during the polarization reversal. Under static electric field, polarization rotation from M C to R occurs and, as the field increases, phase transition from M C to tetragonal ͑T͒ phase takes place. In the vicinity of regions where M C -T phase transition takes place, polarization reversal of M C phase is observed, which is attributed to the local stress field from the strain compatibility between the transitioned area and the nontransitioned area. With the removal of the field, T and M C phases retain while R phase reverses to M C phase. The results demonstrate that the energy differences among M C , R, and T phases are rather slim. Accordingly, the multiphase coexistence and polarization rotation under both cyclic and static electric loadings might be responsible for the ultrahigh piezoelectric response of the ͓001͔-oriented rhombohedral Pb͑Mg 1/3 Nb 2/3 ͒O 3 -PbTiO 3 single crystals near the MPB.