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Metal-organic frameworks (MOFs) exhibit significant potential for mitigating carbon emissions due to their high porosity and tunability. Despite numerous reports on CO2 capture by MOF sorbents, a common challenge is their poor selectivity for CO2 over water. Moreover, in-depth studies are much needed to elucidate the relationships among the pore surface structure, hydrophobicity, and CO2 uptake capacity/selectivity. In this work, we investigate the factors influencing CO2 adsorption capacity and selectivity under humidity in a series of isoreticular pillar-layer structures, Ni2(L)2(dabco) (L = bdc, ndc, adc). Our study shows that increasing ligand conjugation not only results in increased hydrophobicity, decreased pore size and BET surface area, but also leads to the change of primary binding sites of water molecules and higher binding energy of CO2, all of which contribute to largely increased CO2 uptake capacity under humid conditions. Additionally, increasing ligand conjugation and consequently hydrophobicity slow down and reduce competitive water adsorption drastically. Notably, the MOF made of ligand with the highest conjugation, Ni2(adc)2(dabco), exhibits significantly enhanced CO2 adsorption in N2/CO2 binary mixtures under relatively high humidity (50% RH), with an increase of ∼31% and ∼36% for the composition of 15/85 and 50/50, respectively, compared to dry conditions. An experimental FTIR study and DFT theoretical calculations confirm that H2O occupies different primary binding site in Ni2(bdc)2(dabco) and Ni2(adc)2(dabco), and under humid conditions a higher binding energy of CO2 is achieved with preferential H2O/CO2 co-adsorption in Ni2(adc)2(dabco), potentially creating additional adsorption sites for CO2

Objective To establish and evaluate the clinical teaching and training model for refresher anesthesiologists. Methods A total of 25 refresher anesthesiologists from the Department of Anesthesiology in Peking Union Medical College Hospital during the period of March to September 2023 were enrolled. They were taught with the clinical teaching and training model, namely 'tutorial system-knowledge update-clinical practice'. The refresher anesthesiologists completed the same structured pre-designed questionnaire at the beginning and the end of training respectively. The scores were recorded and compared to evaluate the effectiveness of the clinical training model. Feedback from refresher anesthesiologists about the teaching and training model was also collected. Results Altogether 84%(21/25) and 100%(25/25) of questionnaires distributed were completed respectively, and 92% students gave positive feedback. The mean score at the end of training (10.1±1.1) was significantly higher than that at the beginning (5.6±1.8)(P < 0.01). Conclusion The 'tutorial system-knowledge update-clinical practice' clinical teaching and training model was significantly useful to elevate the effectiveness of training refresher anesthesiologists and their satisfaction.

With large-scale access to distributed new energy, the power flow form of the distribution network tends to be complex. The distribution loop network rate increases, resulting in serious circulation of the distribution network, which places significant pressure on the loss of the distribution network. The problem of network loss change caused by distributed new energy grid connection, coupled with the inconsistency between load fluctuation and output power change of distributed new energy, will have a significant impact on the safety, reliability, and economic operation of the distribution network. Therefore, it is urgent to have good economic and technical means of power flow control. This paper proposes a minimum network loss optimization control strategy for active distribution networks based on a distributed power flow controller. First, according to the characteristics of the distribution network load and the new energy power supply along the distribution line, the multiple sub-modules of the distributed power flow controller are arranged in sections in the distribution loop network line. The regulation effect of the distributed power flow controller on the voltage and power flow of the distribution loop network is analyzed. The loop network current equation and power loss equation after the distributed power flow controller are constructed, and the power equation with the minimum active loss of the active distribution loop network is derived. Second, the control strategy for minimum network loss of the active distribution network based on the distributed power flow controller is proposed. Finally, the simulation model of the active distribution loop network is constructed by PSCAD/EMTDC. The loss of the loop network before and after the distributed power flow controller is simulated and analyzed, and the effectiveness of the proposed strategy is verified.

General anesthetics can induce neuronal apoptosis, cause structural changes in the developing brain, and lead to long-term cognitive and behavioral changes. However, the effects of early anesthesia exposure on children's intelligence, behavior and neuroimaging outcomes are not consistent in clinical studies, which suggested the complex mechanism of nerve injury caused by early exposure of anesthesia in children. This review summarized the Results from animal studies and clinical evidence in recent years, discussed the potential mechanism of the effect of early anesthesia exposure on neurodevelopment in children, in order to guide the treatment of children and the choice of operation time.

Abstract The energy exchange between series and shunt converters is the basis for the powerful functioning of the unified distributed power flow controller, which can be realized through the 3rd harmonic current. In this paper, based on the established 3rd harmonic equivalent network of unified distributed power flow controller power system, the influence of the additional loss caused by the 3rd harmonic current on the line transmission capacity is analysed. The mathematical relationship between the neutral point voltage of the transformer and the 3rd harmonic current is constructed, and it is simplified according to the different 3rd harmonic currents. By analysing the power relationship of the 3rd harmonic equivalent network, it is found that there is a contradiction between improving the 3rd harmonic output efficiency of the shunt single‐phase converter and reducing the neutral point insulation voltage of the transformer. The constraint conditions of the 3rd harmonic current are simulated by the advanced digital power system simulator. Finally, the method of obtaining the economical and safe 3rd harmonic current value range is summarized, which provides a theoretical basis and reference for the device parameter design.

BACKGROUND: The application of egg white powder (EWP) was subject to its off‐flavor. In the present study, flavourzyme and lactic acid bacteria were used to treat egg white powder (EWP) and the mechanism effects of enzymolysis–fermentation were explored. RESULTS: Compared with the control group, enzymolysis combined with fermentation treatment group (EW‐EF) reduced the four‐representative off‐flavor compounds (geranyl acetone, 1‐octen‐3‐ol, octanal and nonanal) by more than 62.66%. Fermentation produced esters with good flavor, and enzymolysis produced fresh amino acids. Characterization of protein structure indicated that fermentation decreased both fluorescence intensity and surface negative charges, accelerating the aggregation of proteins; enzymolysis promoted aggregation and degradation, improving the stability of the egg white proteins. Meanwhile, enzymolysis broke down the hydrophobic cavities bound to off‐flavor compounds, releasing protein‐bound off‐flavor compounds and removing them through fermentation. CONCLUSION: EW‐EF had the best effect of off‐flavor removal on EWP. The results of the present study could provide a green and effective method for improving the flavor of EWP. © 2024 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]