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Pollen characteristics are very important for Iris interspecific hybridisation. In this study, the pollen viability and male meiosis were studied in yellow-flowered Iris dichotoma (Y2), I. domestica (S3) and their hybrids F1, F2 and BC1 (BC1-Y and BC1-S). The BC1-Y hybrids showed higher pollen viability than that of F1, F2 and BC1-S hybrids, which were between I. dichotoma (26.1%) and I. domestica (35.1%). Two sterile hybrids, F2-1 and BC1-S-1, exhibited more meiotic abnormalities (57.3% and 58.7%) than other individuals. During the first meiotic division, a diffuse diplotene stage was observed for the first time in the genus Iris. The meiotic abnormalities included non-congressed chromosomes, chromosome bridges, lagging chromosomes, unequal division, abnormally oriented spindle fibres, nonsynchronous division and polyad, and resulted in reduced pollen fertility. The relatively high frequency of 2n pollen grains was found in hybrids of BC1-Y-2, BC1-Y-1, BC1-S-2, BC1-S-3 and BC1-S-4. Our research provides a new resource for meiotic behaviour and pollen fertility of the genus Iris.

Developing an intermediate-temperature solid oxide fuel cell (IT-SOFC) is one of the most promising ways of achieving carbon neutrality, but its air-electrode is restricted by the conflict between the sluggish catalytic activity and durability. Herein, an A-site high-entropy perovskite composite La0.2Ba0.2Sr0.2Ca0.2Ce0.2−xCoO3−δ–xCeO2 (LBSCCC–CeO2) air-electrode material is fabricated via a one-step self-constructing strategy, which shows excellent oxygen reduction activity and stability due to the high-entropy structure and the synergy effect between LBSCCC and interfacial CeO2. This work provides a new way of fabricating high-performance air-electrodes in IT-SOFCs. [ABSTRACT FROM AUTHOR]

Herein, we created defects on NH2-MIL-125 to form more nodes of grafted metals, and synthesized a series of hybrid materials (Cu/d-NH2-MIL-125 and CuNPs/d-NH2-MIL-125 with 1,2, and 4 wt % of Cu nanoparticles) that were used as photocatalysts of the hydrogen evolution reaction and dehydrogenation of tetrahydroisoquinoline. At the optimal relative amount of Cu, namely 2 wt %, the hydrogen evolution reaction and dehydrogenation of tetrahydroisoquinoline showed rates of 1326.55 μmol g−1 h−1 and 427.15 μmol g−1 h−1, respectively. This new photocatalyst could effectively improve the e−/h+ separation efficiency, enriching the investigation of MOFs in the field of photocatalytic hydrogen evolution. [ABSTRACT FROM AUTHOR]

As heat-resistant and wear-resistant materials, the aluminum matrix composites based on in-situ SiO2-Al reaction need to be systematically studied at high temperature. In this research, the SiO2 precursor particles with the average diameters of 'D = 30 μm and 'D = 250 μm were used to study the microstructures and creep behavior of the aluminum matrix composites. Unlike the AMCS particle-reinforced structure of D = 30 μm precursor, the sandwich structure reinforced by SiO2 core and Al2O3 layer was found in AMCS of D = 250 μm n precursor. The formation mechanism of these two microstructures could be rationalized by concerning the reaction kinetics. The creep resistance of the composite sample with d = 30 μm precursor was more excellent than that of the sample with d = 250 μm precursor. According to the threshold analysis for these composites, the correlation between creep strains rate and the effective stress could be rationalized by a true stress exponent of 3, suggesting the creeping mode of these composites was viscous to glide of dislocation. [ABSTRACT FROM AUTHOR]

Metal–organic frameworks (MOFs) provide a platform to design new heterogeneous catalysts for catalytic CO2 reduction, but selective formation of C2 valuable liquid fuel products remains a challenge. Herein, we propose a strategy to synthesize composites by integrating MoS2 nanosheets into hierarchically porous defective UiO‐66 (d‐UiO‐66) to form Mo‐O‐Zr bimetallic sites on the interfaces between UiO‐66 and MoS2. The active interfaces are favorable for the efficient transfer of photo‐generated charge carriers and for promoting the activity, whereas, the synergy of the components at the interfaces achieves selectivity for C2 production. The d‐UiO‐66/MoS2 composite facilitates the photo‐catalytic conversion of gas phase CO2 and H2O to CH3COOH under visible light irradiation without any other adducts. The evolution rate and selectivity of CH3COOH reached 39.0 μmol g−1 h−1 and 94 %, respectively, without any C1 products, suggesting a new approach for the design of highly efficient photocatalysts of CO2 for C2 production. Theoretical calculations demonstrate the charge‐polarized Zr‐O‐Mo aided the C−C coupling process with the largely reduced energy barrier. [ABSTRACT FROM AUTHOR]

Carbon‐based hole transport material (HTM)‐free CsPbI2Br perovskite solar cells (C‐PSCs) have garnered considerable attention due to their super thermal stability. The energy‐level mismatch between the CsPbI2Br perovskite and carbon electrodes, however, results in major energy loss and reduced power conversion efficiency (PCE) of C‐PSCs. Herein, 1‐butyl‐3‐methylimidazolium tetrafluoroborate (BMIMBF4) is used to manage the energy level, reduce defect densities, and improve the interface quality between CsPbI2Br and carbon electrodes. Preliminary results demonstrate that the BMIMBF4 modifier can passivate the surface defects of the perovskite film and reduce the energy‐level mismatch between the CsPbI2Br layer and the carbon electrode. A PCE of 14.03% is achieved by introducing BMIMBF4 which is improved by 23% compared with the control device (11.37%). Moreover, stability—whether in the case of C‐PSCs or CsPbI2Br films—is also improved. [ABSTRACT FROM AUTHOR]

Pollen characteristics are very important for Iris interspecific hybridisation. In this study, the pollen viability and male meiosis were studied in yellow-flowered Iris dichotoma (Y2), I. domestica (S3) and their hybrids F1, F2 and BC1 (BC1-Y and BC1-S). The BC1-Y hybrids showed higher pollen viability than that of F1, F2 and BC1-S hybrids, which were between I. dichotoma (26.1%) and I. domestica (35.1%). Two sterile hybrids, F2-1 and BC1-S-1, exhibited more meiotic abnormalities (57.3% and 58.7%) than other individuals. During the first meiotic division, a diffuse diplotene stage was observed for the first time in the genus Iris. The meiotic abnormalities included non-congressed chromosomes, chromosome bridges, lagging chromosomes, unequal division, abnormally oriented spindle fibres, nonsynchronous division and polyad, and resulted in reduced pollen fertility. The relatively high frequency of 2n pollen grains was found in hybrids of BC1-Y-2, BC1-Y-1, BC1-S-2, BC1-S-3 and BC1-S-4. Our research provides a new resource for meiotic behaviour and pollen fertility of the genus Iris. [ABSTRACT FROM AUTHOR]