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The flowering time and plant architecture of Brassica napus were significantly associated with yield. In this study, we found that the BREVIPEDICELLUS/KNAT1(BP) gene regulated the flowering time and plant architecture of B. napus. However, the precise regulatory mechanism remains unclear. We cloned two homologous BP genes, BnaBPA03 and BnaBPC03, from B. napus Xiaoyun. The protein sequence analysis showed two proteins containing conserved domains KNOX I, KNOX II, ELK, and HOX of the KONX protein family. The CRISPR/Cas9 knockout lines exhibited early budding and flowering time, coupled with floral organ abscission earlier and a larger leaf angle. On the contrary, overexpression plants displayed a phenotype that was the inverse of these characteristics. Furthermore, we observed upregulation of gibberellin and ethylene biosynthesis genes, as well as floral integrator genes in knocked‐out plants. The results revealed that BnaBPs play a role in flowering time, floral organ abscission, and leaf angle as well as germination processes mediated. Additionally, BnaBPs exerted an impact on the biosynthesis pathways of ethylene and GA. [ABSTRACT FROM AUTHOR]

As one of the most promising cathodes for sodium-ion batteries (SIBs), the layered transition metal oxides have attracted great attentions due to their high specific capacities and facile synthesis. However, their applications are still hindered by the problems of poor moisture stability and sluggish Na+ diffusion caused by intrinsic structural Jahn—Teller distortion. Herein, we demonstrate a new approach to settle the above issues through introducing K+ into the structures of Ni/Mn-based materials. The physicochemical characterizations reveal that K+ induces atomic surface reorganization to form the birnessite-type K2Mn4O8. Combining with the phosphate, the mixed coating layer protects the cathodes from moisture and hinders metal dissolution into the electrolyte effectively. Simultaneously, K+ substitution at Na site in the bulk structure can not only widen the lattice-spacing for favoring Na+ diffusion, but also work as the rivet to restrain the grain crack upon cycling. The as achieved K+-decorated P2-Na0.67Mn0.75Ni0.25O2 (NKMNO@KM/KP) cathodes are tested in both coin cell and pouch cell configurations using Na metal or hard carbon (HC) as anodes. Impressively, the NKMNO@KM/KP||Na half-cell demonstrates a high rate performance of 50 C and outstanding cycling performance of 90.1% capacity retention after 100 cycles at 5 C. Furthermore, the NKMNO@KM/KP||HC full-cell performed a promising energy density of 213.9 Whkg−1. This performance significantly outperforms most reported state-of-the-art values. Additionally, by adopting this strategy on O3-NaMn0.5Ni0.5O2, we further proved the universality of this method on layered cathodes for SIBs. [ABSTRACT FROM AUTHOR]

It is essential to explore high efficient catalysts for nitrogen reduction in ammonia production. Based on the first-principles calculation, we find that B/g-C2N can serve as high performance photocatalyst in N2 fixation, where single boron atom is anchored on the g-C2N to form B/g-C2N. With the introduction of B atom to g-C2N, the energy gap reduces from 2.45 eV to 1.21 eV and shows strong absorption in the visible light region. In addition, N2 can be efficiently reduced on B/g-C2N through the enzymatic mechanism with low onset potential of 0.07 V and rate-determining barrier of 0.50 eV. The "acceptance-donation" interaction between B/g-C2N and N2 plays a key role to active N2, and the BN2 moiety of B/g-C2N acts as active and transportation center. The activity originates from the strong interaction between 1π1π* orbitals of N2 and molecular orbitals of B/g-C2N, the ionization of 1π orbital and the filling of 1π* orbital can increase the N≡N bond length greatly, making the activation of N2. Overall, this work demonstrates that B/g-C2N is a promising photocatalyst for N2 fixation. [ABSTRACT FROM AUTHOR]

The structural evolutions and electronic properties of AulPtm (l + m ≤ 10) clusters are investigated by using the first-principles methods. We use the inverse design of materials using the multi-objective differential evolution (IM2ODE) package to globally search the equilibrium structures and investigate the evolving trend from a two-dimensional structure to a three-dimensional structure on horizontal extension and vertical extension for AulPtm (l + m ≤ 10) clusters. The three-dimensional stable geometry of Au8Pt and Au8Pt2 is discovered for the first time in our work. We also notice that the equilibrium structures of AulPtm (l + m = 10 and l ≤ 8) tend to form a tetrahedral geometry and can be obtained by replacing the Au atom in the most stable structure of Aul+1Ptm−1 with the Pt atom, where Pt atoms assemble together and occupy the center of clusters and Au atoms prefer to lie on the vertex or edge position. The average binding energy (Eb) is mostly decided by Pt–Pt bond numbers, namely the numbers of Pt atoms, followed by Au–Pt bond numbers. The second-order energy difference (Δ2Ev and Δ2Eh) and the nearest-neighbor energy difference (Δ4Enn) show that Au6Pt, Au4Pt2, Au3Pt3, Au2Pt4 and AuPt7 clusters exhibit high relative physical stability, so we suggest that these clusters could be defined as the magic number clusters for AulPtm (l + m ≤ 10) clusters. The HOMO–LUMO energy gap (Eg), adiabatic ionization potential (AIP) and the adiabatic electron affinity (AEA) are also investigated to elaborate the relative electronic stability of all the clusters. [ABSTRACT FROM AUTHOR]

The catalytic properties of the magic gold–platinum bimetallic clusters (Au4Pt2 and Au6Pt) for the reduction of SO2 by CO, without or with preadsorbing CO molecules, are firstly investigated using density functional theory calculations. We find that the catalytic activities improve effectively with the preadsorption of CO onto the catalysts and that the catalytic activities of Au6Pt(CO)n are better than those of Au4Pt2(CO)n as more CO molecules are adsorbed onto the catalysts. During the reaction process, the Au4Pt2(CO)n clusters always keep two-dimensional morphologies except for when n = 5 and the Au6Pt(CO)n clusters have three-dimensional geometries except for when n = 0. The most stable adsorption site for SO2 molecules on the catalysts is the site of preadsorbing the next CO molecule on the corresponding catalysts. The largest activation energy (Emaxa) is related to the metal 5d (M-5d) band center and the charge transfer (Ct) as well as the bond length (Rb) between COS and the catalyst contribute to the desorption energy (Ed) of COS corporately. We propose that Au6Pt(CO)6 is a cost-effective gold–platinum bimetallic catalyst for the reduction of SO2 by CO. [ABSTRACT FROM AUTHOR]

Using density functional theory, we have investigated the catalytic properties of bimetallic complex catalysts PtlAum(CO)n (l + m = 2, n = 1–3) in the reduction of SO2 by CO. Due to the strong coupling between the C-2p and metal 5d orbitals, pre-adsorption of CO molecules on the PtlAum is found to be very effective in not only reducing the activation energy, but also preventing poisoning by sulfur. As result of the coupling, the metal 5d band is broadened and down-shifted, and charge is transferred from the CO molecules to the PtlAum. As SO2 is adsorbed on the catalyst, partial charge moves to the anti-σ bonding orbitals between S and O in SO2, weakening the S–O bond strength. This effect is enhanced by pre-adsorbing up to three CO molecules, therefore the S–O bonds become vulnerable. Our results revealed the mechanism of the excellent catalytic properties of the bimetallic complex catalysts. [ABSTRACT FROM AUTHOR]

Based on the density functional theory, we investigate negatively charged clusters , which show significant catalytic properties in the simultaneous removal of N2O and CO. We find that in these clusters, the platinum atom acts as the adsorption center for N2O, the gold and Pt atoms act as electron donors during the reaction, and the charge transfers from the bimetallic cluster to the N2O molecule. As the proportion of Au in the cluster increases, the d band center shifts down further away from the Fermi level, meanwhile more charge is transferred to the N2O molecule, resulting in weaker N–O bond strength. Therefore bimetallic cluster shows better catalytic properties than the other clusters, especially pure Pt4− and Au4− clusters. This means that there is a synergetic effect between the Pt and Au atoms in the negatively charged bimetallic clusters. Our results help to reveal the mechanism of bimetallic clusters as excellent catalysts. [ABSTRACT FROM AUTHOR]