Xe is only produced by cryogenic distillation of air, and its availability is limited by the extremely low abundance. Therefore, Xe recovery after usage is the only way to guarantee sufficient supply and broad application. Herein we demonstrate DD3R zeolite as a benchmark membrane material for CO2/Xe separation. The CO2 permeance after an optimized membrane synthesis is one order magnitude higher than for conventional membranes and is less susceptible to water vapour. The overall membrane performance is dominated by diffusivity selectivity of CO2 over Xe in DD3R zeolite membranes, whereby rigidity of the zeolite structure plays a key role. For relevant anaesthetic composition (<5 % CO2) and condition (humid), CO2 permeance and CO2/Xe selectivity stabilized at 2.0×10−8 mol m−2 s−1 Pa−1 and 67, respectively, during long‐term operation (>320 h). This endows DD3R zeolite membranes great potential for on‐stream CO2 removal from the Xe‐based closed‐circuit anesthesia system. The large cost reduction of up to 4 orders of magnitude by membrane Xe‐recycling (>99+%) allows the use of the precious Xe as anaesthetics gas a viable general option in surgery.

ZnO-Al 2 O 3 derived from layered double hydroxides (ZnAl-LDH) was successfully applied for dispersion of Pd-Ag bimetallic catalysts for the selective hydrogenation of acetylene to ethylene and the Pd-Ag/ZnO-Al 2 O 3 catalyst showed the best catalytic performance among the prepared samples. It was found that the catalyst carrier of ZnO-Al 2 O 3 metal-oxides derived form ZnAl-LDH could significantly suppress the over-hydrogenation of acetylene to obtain the relatively higher selectivity of ethylene. The introduction of Ag restricted efficiently the formation of coke because of the oligomerization reaction, which was further evidenced by thermal gravimetric analysis. The se-lectivity towards ethylene was in the order of Pd-at a high conversion level. As the thermal gravimetric and differential temperature analysis (TG-DTA) revealed, Pd-Ag intermetallic catalyst on the ZnO-Al 2 O 3 support showed less coke formation.

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Xe is only produced by cryogenic distillation of air, and its availability is limited by the extremely low abundance. Therefore,Xerecovery after usage is the only way to guarantee sufficient supply and broad application. Herein we demonstrate DD3R zeolite as ab enchmark membrane material for CO 2 /Xe separation. The CO 2 permeance after an optimized membrane synthesis is one order magnitude higher than for conventional membranes and is less susceptible to water vapour.T he overall membrane performance is dominated by diffusivity selectivity of CO 2 over Xe in DD3R zeolite membranes,whereby rigidity of the zeolite structure playsakey role. Forr elevant anaesthetic composition (< 5% CO 2 )a nd condition (humid), CO 2 permeance and CO 2 /Xe selectivity stabilized at 2.0 10 À8 mol m À2 s À1 Pa À1 and 67, respectively,d uring long-term operation (> 320 h). This endows DD3R zeolite membranes great potential for on-stream CO 2 removal from the Xe-based closed-circuit anesthesia system. The large cost reduction of up to 4o rders of magnitude by membrane Xerecycling (> 99 + %) allows the use of the precious Xe as anaesthetics gas av iable general option in surgery.

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We demonstrate a high-power laser system with a high-quality near-field beam by using a liquid-crystal spatial light modulator (SLM). An efficient spatial beam shaping algorithm is discussed which can improve the output nearfield beam quality effectively. Both small-signal and large-signal amplification situation of the laser are considered in the beam shaping algorithm. The experimental results show that the near field fluence modulation of output is improved from 1.99:1 to 1.26:1 by using the liquid-crystal SLM. Obvious uniform spatial fluence distribution and near-field beam quality improvement are observed.

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