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Pressure swing adsorption (PSA) coupling with molecular sieves, especially the Li low silica X (Li‐LSX) zeolite, adsorption technology is widely used in O2 generator instrument under plateau environment. However, the studies of N2 and O2 adsorption and separation properties on zeolite under plateau environment are still obscure to date. In this work, the influence of N2 and O2 adsorptions on the LSX zeolites in harsh plateau environment (3000 ‐ 5000 m) was investigated by Grand Canonical Monte Carlo (GCMC) simulations. Three kinds of LSX zeolites including Li‐LSX, Ag‐LSX and LiCa‐LSX were taken into consideration. The simulation results indicate that the adsorption amount and affinity of both N2 and O2 elevate with the increasing altitude and following the order of Ag‐LSX > Li‐LSX > LiCa‐LSX. The N2 adsorption was dominated over all three LSX zeolites, leaving O2 much easier to permeate through the LSX zeolites. The isosteric adsorption heat and adsorption density results further proved that N2 and O2 have extremely different adsorption strategies. Moreover, the selectivity and separation coefficients based on ideal adsorption solution theory (IAST) were calculated from GCMC simulations, and the results indicate Ag‐LSX has the highest diffusion selectivity and the steadiest diffusion coefficient among the three LSX zeolites. These findings may contribute to the N2/O2 separation molecular sieves for plateau applications by tailoring the LSX zeolite with different extra‐framework cations.

Mental fatigue (MF) jeopardizes performance and safety through a variety of cognitive impairments and according to the complexity loss theory, should represent “complexity loss” in electroencephalogram (EEG). However, the studies are few and inconsistent concerning the relationship between MF and loss of complexity, probably because of the susceptibility of brain waves to noise. In this study, MF was induced in thirteen male college students by a simulated flight task. Before and at the end of the task, spontaneous EEG and auditory steady-state response (ASSR) were recorded and instantaneous frequency variation (IFV) in alpha rhythm was extracted and analyzed by multiscale entropy (MSE) analysis. The results show that there were significant differences in IFV in alpha rhythm either from spontaneous EEG or from ASSR for all subjects. Therefore, the proposed method can be effective in revealing the complexity loss caused by MF in spontaneous EEG and ASSR, which may serve as a promising analyzing method to mark mild mental impairments.

The cage-based MOFs have been attracted widely interest due to their large internal ordered cavities and small windows, which can selectively capture and separate the guest molecules. Herein, a unique...

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