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Based on morphological and molecular phylogenetic studies, Semiaquilegia danxiashanensis, a new species from Danxia Shan in northern Guangdong, southern China, is described and illustrated. This species is easily distinguishable from each of other three known species in the genus by characters of the flowers and fruits. In addition, molecular phylogenetic analyses of both the nuclear ITS and the plastid trnL-F region strongly supported S. danxiashanensis as a separate species from other species of Semiaquilegia. We provide a detailed morphological and habitat description, distribution, as well as colour photographs and illustrations of the new species.

Due to the abundance and economic viability of Na resources, Na–O2 batteries are regarded as promising energy storage devices in achieving the carbon neutrality goals, featuring an ultra-high theoretical energy density. Nevertheless, the slow ion diffusion kinetics hinders the applications of batteries. Spin-induced single-atom catalysts (SACs) offer a promising avenue to ameliorate the activation process of the battery reaction. Herein, we study the adsorption–activation mechanism of O2 on six spin-induced SACs (i.e., MnN3, MnN4, CoN3, CoN4, NiN3, and NiN4) in Na–O2 batteries. We find that oxygen in mono-vacancy catalysts with high spin states favors the side-on adsorption mode. This mode enhances the coupling between the 3dxy orbital of metal and O2, and alters the active center structures which further reduces the reaction overpotential by cutting down the OER potential. Moreover, we establish the scaling relationship between the oxygen adsorption energy and battery overpotential with a correlation coefficient of 0.98. Our study elucidates the evolution of the SAC active center induced by a shift of spin states and its impact on the oxygen adsorption–activation process which strongly determines the battery performance. The established structure–activity relationship of spin induced SACs may shed light on the catalyst modification involving the oxygen adsorption and activation to achieve a better performance. [ABSTRACT FROM AUTHOR]

In the Visible Light Communication (VLC) system based on circle Color Shift Keying (CSK) modulation constellation, the bit error rate performance is poorer under certain number of modulation order. In this paper, we optimize the constellation point design, in keeping the constellation points under the condition of invariable pointing triangle center redesigned constellation structure. We change the constellation point location and increase the minimum code distance between constellation points to improve the bit error rate performance. In order to further improve the transmission quality of VLC signal, the principle of Finite State Machine (FSM) is introduced to carry out joint coding design to further improve bit error rate. Finally, simulation verification and performance analysis are carried out. The simulation results show that, compared with the traditional CSK modulation technology, the optimized extended circular constellation CSK and FSM combined coding proposed in this paper have better bit error rate performance. The gain of 4 Combination Coding-Finite State Machine (CC-FSM) code is 2.1 dB compared with that of 4-CSK, and the gain of 8CC-FSM code is 1.7 dB compared with that of 8-CSK.

Recently, enormous research passion has been devoted to reduce air pollution caused by vehicle emissions. Effective vehicle emission control method is to convert exhaust pollutants by placing catalyst in the exhaust pipe. However, the major stumbling block is that a large portion of emission occurs in the initial 20–30 s during the engine cold-start stage, before catalyst can reach its operating temperature. To address the challenge, herein we developed a catalyst utilizing Pd and Rh as active components, Ce-Zr solid solution as assistant, γ-Al2O3 as coating and Fe-Cr-Al as supporter. The catalyst component was optimized (atom ratio of Ce:Zr is 6:4, mass ratio of Pd:Rh is 8:2, total weight of Pd and Rh is 1.2 g/L, pore density is 700 pores/inch2) and high-frequency electrical heating technique was employed to decrease operating temperature from 400°C to 350°C and improve exhaust conversion efficiency by 78%.

The past decades have witnessed several well-known beautiful conclusions on four con-cyclic points. With highly promising research value, we profoundly studied circumscribed ellipses of convex quadrilaterals in this paper. Using tools of parallel projective transformation and analytic geometry, we derived several theorems including the proof of the existence of circumscribed ellipses of convex quadrilaterals, the properties of its minimal coverage area, and locus center, respectively. This simple approach lays a solid foundation for its application to three-dimensional situations, which is namely the circumscribed quadric surface of a solid figure and its wide-range utility in construction engineering. Meanwhile, we have a new insight into innate connection of conic sections as well as a taste of beauty and harmony of geometry.

Zn–iodine (I2) battery, as a promising energy storage device, especially under high I2 loading, is harassed by the shuttle effect of the soluble polyiodide intermediates. Herein, the bifunctional role of 2D carbon nanosponge with rich P‐dopant (4.2 at%) and large specific surface area (1966 m2 g−1) in anchoring I2/Ix− (x = 1, 3 or 5) and catalyzing their mutual conversion is reported. Both experiment and computational results reveal the transfer of electrons from the P‐doped site to iodine species, showing strong interfacial interaction. When being used as a host, it possesses high specific capture capacity for I2 (3.34 giodine g−1 or 1.6 mgiodine m−2) and Ix− (6.12 gtriiodide g−1 or 3.1 mgtriiodide m−2), which thus effectively suppresses the shuttle effect, supported by in situ UV–vis and Raman spectra. In addition to the strong interfacial interaction that favors iodine conversion, the P‐doped sites can also catalyze the conversion of I5− to I2, which is the rate‐determining step. Consequently, Zn–I2 batteries under a high I2 content (70 wt%) deliver high specific capacity (220.3 mAh g−1), superior Coulombic efficiency (>99%), and low self‐discharge rate; moreover, they can also operate steadily at 2 A g−1 with ignorable capacity decay for 10 000 cycles. [ABSTRACT FROM AUTHOR]