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The problem of aircraft entering and exiting water is a complex, nonlinear, strongly disturbed, and multi-coupled multiphase flow problem, which involves the precise capture of the air/water interface and the multi-coupling interaction between aircraft, water, and air. Moreover, due to the large difference in medium properties during the crossing, the load on the body will suddenly change. In this paper, the VOF (volume of fluid) algorithm is used to capture the liquid surface at the air/water interface, and since body movement is involved in this process, the overset grid technology is used to avoid the traditional dynamic grid deformation problem. In the process of this numerical simulation prediction, the effects of different water-entry angles and different water-entry heights on the body load and attitude of the trans-medium aircraft, as well as the cavitation evolution law of the body water entry are analyzed. On this basis, to simulate the authenticity and complexity of the water-entry environment, numerical wave-making technology was introduced to analyze the water-entry load, posture, and cavitation evolution law of the body under different wave environments. The numerical parameters under the condition of wave and no wave are compared, and the difference in water-entry performance under the condition of wave and no wave is analyzed.

Electrocatalytic CO2 reduction (CO2ER) to valuable chemicals, for example, HCOOH have received widespread attention, which still suffers from moderate Faradaic efficiency with low current regarding the wide industrial application of HCOOH. Herein, we employed a strategy of modifying electronic metal‐support interaction (EMSI) by fabricating Bi nanoparticles supported Ni‐modified Bi2O2CO3 (Bi/Ni‐BOC) heterostructure. The obtained Bi/Ni‐BOC exhibited high formate Faradic efficiency (FEHCOOH) of 97% at −2.1 V (vs. Ag/AgCl) and above 90% within broad potential range (−1.7 to −2.2 V) in flow cell with superior stability at high current density of ~220 mA cm−2, and formate concentration can reach 2.4 mmol h−1 cm−2 at −2.3 V. In/ex situ x‐ray absorption fine structure (XAFS) and density functional theory (DFT) calculation indicated that Ni doping promoted the enhancement of EMSI, which improved the generation and stable existence of electron‐rich Bi to boost CO2 activation and *OHCO hydrogenation, thus facilitating highly‐efficient formate production with hydrogen evolution reaction (HER) inhibition. [ABSTRACT FROM AUTHOR]

Photocatalytic CO2 reduction (CO2PR) into multi‐carbon products (especially C2H4) is a highly attractive route for global carbon cycle, however, which is seriously limited by sluggish C‐C coupling kinetics and competitive hydrogen evolution reaction (HER) and so on. Herein, the fabrication of a novel supramolecular assembly of NiAl‐Fe‐TCPP is reported by intercalating iron porphyrin (Fe‐TCPP) into NiAl‐layered double hydroxide (NiAl‐LDH), and the resultant NiAl‐Fe‐TCPP exhibit superior catalytic performance on CO2PR to C2H4 under visible light irradiation in presence of photosensitizer. A high C2H4 selectivity up to 93.4% in the carbon‐containing products with the production rate as high as 24.7 µmol h−1 can be achieved over NiAl‐Fe‐TCPP. The ex/in situ X–ray absorption spectoscopy (XAS) indicates that the electron transfer between NiAl‐LDH and Fe‐TCPP can promote the generation of low‐valence of Fe sites, resulting in the efficient production of C2H4. The spin‐polarized density functional theory (DFT) calculations find that the synergistic mechanism that CO2 molecules are activated to CO on NiAl‐LDH and then spilled to Fe‐TCPP and coupled to COCHO#, which is further reduced to C2H4, are feasible in the perspective of Gibbs free energy. Moreover, the strong host‐guest interactions between NiAl‐LDH and Fe‐TCPP lead to the promoted photocatalytic activity and superior cycle stability. [ABSTRACT FROM AUTHOR]

Layered double hydroxides (LDHs) have shown great potential as adsorbents for the removal of heavy metals. Nevertheless, how the host‐guest interactions of LDHs affect the removal mechanism remains to be less explored. Herein, CO32−/NO3−/SO42−/Cl− intercalated MgAl‐LDHs with different host‐guest interactions were fabricated and their removal mechanism for Cd2+ was investigated. The removal capacity increased in the order of MgAl−CO3 (127.3 mg/g)