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The creation of frustrated Lewis pairs on catalyst surface is an effective strategy for tuning CO2 activation. The critical step in the formation of frustrated Lewis pairs is the spatial effect of proximal Lewis acid‐Lewis base pairs. Here, we demonstrate a facile surface functionalization methodology that enables hydrogen bonding between N and H atoms to mediate the construction of frustrated Lewis pairs in poly(heptazine imide), thereby increasing the propensity to activate CO2 molecules. Experimental and theoretical results show that the construction of active hydrogen bonding regions can facilitate the bending of CO2 molecules. Furthermore, the delocalization of electron clouds induced by the hydrogen bonding‐mediated frustrated Lewis pairs can promote the heterolytic cleavage and photocatalytic conversion of CO2. This work highlights the potential of utilizing hydrogen bonding‐mediated strategy in heterogeneously photocatalytic activation of CO2 over polymer materials. [ABSTRACT FROM AUTHOR]

To study the initiation and development of interfacial electrical damage in multi-layer dielectrics, an aging test of 3-layer polyimide films was conducted under pulsed voltage with a repetitive frequency of 500 Hz and a maximal amplitude of 30 kV. The variation in the damage morphology with the number of applied pulses was analyzed by a statistical method. The circuit current and partial discharge at different aging stages was measured, and the Fourier transform infrared spectrum analysis results of the aged and unaged sample regions were compared. The results demonstrate that the partial discharge in the dielectric interface gap, which is unavoidable in manufacturing, is the main cause of damage. It initiates from the interface and grows into the interior of the dielectric with the application of pulses. When there are no macroscopic defects on dielectric films, damage presents a punctiform morphology. The damage process can be divided into the following three stages: surface roughening damage, steady growth stage of damage points, and pre-breakdown stage. Differing from dielectrics without macroscopic defects, dielectrics with original void defects present transverse dendritic damage channels that initiate from the edge of the defect. [ABSTRACT FROM AUTHOR]

In the 21st century, more and more adults have psychological problems of varying degrees, which bother them and make their quality of life decline a lot. But going back to their childhood, they all experienced some “abnormal” stimuli. This article explores the effects of these childhood anomalies on individuals as adults. A lot of previous research has shown that some stressful events really do have an impact on personality. Those impact cannot be eliminated without any intervention by professional psychologist. The author hopes that this paper can give some guidance to individuals who are experiencing or have experienced these “abnormal” events, and hope that everyone can have a healthy mind. Future research should be more focus on People’s mental health under the epidemic. Many people have lost relatives or experienced serious psychological trauma because of the unequal distribution of medical treatment in the epidemic, and these injuries are lingering in their hearts, and even every time they get sick and cold, they will think of these wounds. It is hoped that future research will focus more on trauma interventions and treatments in these epidemics.

Photocatalysis is extensively implemented in organic pollutant degradation, and the critical point is to develop outstanding and stable photocatalysts. Herein, the synthesis of coral reef-like α-Bi2O3/BiOBr heterostructure photocatalysts involves the in situ growth of BiOBr nanosheets onto α-Bi2O3, with the latter derived through calcination utilizing a bismuth-based metal–organic framework (CAU-17) as the precursor. Under simulated sunlight, the 20% α-Bi2O3/BiOBr heterojunction degraded nearly 97.7% of RhB in 60 min, while pure α-Bi2O3 and BiOBr nanosheets degraded only 7.8 and 65.3%, respectively. Furthermore, the 20% α-Bi2O3/BiOBr nanocomposite exhibited superior recycling stability, degrading 86.6% RhB after four cyclic experiments. This is attributed to the fact that the nanoscale α-Bi2O3 material obtained by calcination can retain the exoteric diffusion channels of CAU-17, making α-Bi2O3/BiOBr heterojunctions have an enormous specific surface area, providing more adsorption sites and promoting their photocatalytic capacity. Free radical capture tests and electron paramagnetic resonance measurements indicated that h+ and •O2– were the primary active substances during photodegradation. On the basis of that, a feasible photodegradation mechanism of type II α-Bi2O3/BiOBr heterojunctions was proposed. This study opens up the possibility of designing type II heterojunctions with MOFs as precursors for dye degradation. [ABSTRACT FROM AUTHOR]