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The jet impact‐negative pressure deamination reactor (JI‐NPDR) is a new type of continuous and efficient deamination equipment. The study of the random flow pattern of porous jet impingement in the reactor under negative pressure conditions is an important issue. In this work, the signal processing method based on wavelet transform is used to analyze the characteristics of random flow signals in the reactor. Meanwhile, an analog similar signal is built and three sets of Gaussian white noise with various signal‐to‐noise ratios are employed via the MATLAB platform. Based on the adjustment of threshold function, threshold, decomposition level and other parameters of wavelet transform, the noise ratio (SNR) and mean squared error (MSE) are used to evaluate the wavelet denoising effect. And then, the optimal denoising scheme for the obtained signal will be applied in processing the vacuum flow signal collected inside the deamination reactor. Subsequently, the 8‐layer wavelet decomposition is investigated by using sym7 as the wavelet basis, soft threshold function, and heursure threshold for signal denoising. Then, the analog signal is fed back through the results of the actual signal denoising, and the number of wavelet decomposition layers is adjusted from 8 to 9 layers to optimize the original wavelet denoising combination. By analyzing the low‐frequency and high‐frequency parts of the signal spectrum before and after denoising, it was found that wavelet transform can effectively denoise the fluid signal in the reactor. [ABSTRACT FROM AUTHOR]

Currently, photo-assisted peroxymonosulfate (PMS) activation has received more and more attention in the degradation of wastewater pollutants. In this paper, the Fe 3 O 4 @CQDs magnetic nanocatalyst was successfully prepared by modifying α-Fe 2 O 3 , and Rhodamine B (RhB) was degraded by activating PMS under visible light. Moreover, in order to explore the reason why Fe 3 O 4 @CQDs was more beneficial to the activation of PMS than α-Fe 2 O 3 at the microscopic level and reaction mechanism, the corresponding DFT calculations were performed. The results revealed that the degradation efficiency of RhB reached 98% in 35 min. Subsequently, the quenching experiments and EPR tests jointly verified that SO 4 •-, •OH, O 2 •- free radical pathway and 1O 2 , h + non-free radical pathway participated in the degradation of RhB in the Fe 3 O 4 @CQDs + PMS + light system. The adsorption energy reached −5.247 eV with Fe 3 O 4 @CQDs adsorbed PMS by DFT calculation. The electron enrichment and charge redistribution can be apparently observed during the adsorption of PMS at Fe 3 O 4 @CQDs nanocatalyst. It was confirmed that the embedding of CQDs effectively regulated the electron transfer efficiency at the Fe 3 O 4 @CQDs interface to promote the improvement of electrical conductivity. It was more conducive to forming Fe(Ⅲ) to Fe(Ⅱ) cycles, and then the ability of the catalyst to activate PMS was improved. • Fe 3 O 4 @CQDs magnetic nanocatalyst was synthesized by hydrothermal method. • The degradation efficiency of RhB reached 98% within 35 min. • The catalyst had excellent repeatability. • The Fe 3 O 4 @CQDs + PMS + light system can promote more ROS production. • CQDs in the catalyst accelerated the charge transfer and promoted the Fe(Ⅱ)/Fe(Ⅲ) cycle. [ABSTRACT FROM AUTHOR]

The conventional treatment of pharmaceutical wastewater exhibits expensive costs and inefficiency. In this paper, novel Fe–Mn bimetallic catalysts were synthesized by Mn doped different precursors of morphologies α-Fe 2 O 3 with one pot hydrothermal method, and then activated peroxymonosulfate (PMS) to degrade tetracycline (TC), as a model of medicaments in the water environment. Meanwhile, density functional theory (DFT) calculations confirmed the Fe–Mn bimetallic catalyst was favored for activating PMS. Notably, the treatment rate of TC was 90.7% within 60 min in the FMDS-3 + PMS system. Besides, the FMDS-3 bimetallic catalyst presented excellent repeatability, and its system treatment rate achieved 75% after repeated use nine times. Subsequently, the adsorption energy reached −6.857 eV as FMDS-3 adsorbed PMS, and differential charge density also clearly indicated that electron transfer was more active in the FMDS-3 + PMS system. In further research on the density of states, the electron spin of the FMDS-3 bimetallic catalyst made its characteristic peak closer to the Fermi level, which promoted the adsorption of PMS on its catalyst. The degradation mechanism revealed that SO 4 •-, •OH, O 2 •-, 1O 2 , and e− were involved in the degradation of TC. Then liquid chromatography-mass spectrometry (LC-MS) and toxicity assessment software tools (TEST) confirmed that intermediate product toxicity during TC degradation was much lower than that of TC. Finally, the removal rates of NH 3 −N, TOC and COD within 100 min in the FMDS-3 + PMS system were 78.5%, 40.5% and 80.4% respectively in the actual pharmaceutical wastewater. The study can provide support for the effective treatment of pharmaceutical wastewater. [ABSTRACT FROM AUTHOR]

• A self-supporting electrode modify by Mott-Schottky heterostructure is designed. • The heterostructure induces 3D nucleation of Li 2 S via built-in electric field. • The heterostructure accelerates the adsorption and conversion of polysulfides. • DFT reveals interfacial charge transfer between the heterostructure and polysulfides. Lithium-sulfur (Li-S) batteries have become a research focus due to their high theoretical specific capacity and energy density. The shuttle effect and slow sulfur conversion kinetics of lithium polysulfides (LiPSs) severely hindered their practical application. Here, a N-doped carbon nanofiber self-supporting electrode modified with cobalt selenide/nickel selenide as a sulfur carrier (CoSe 2 /NiSe 2 @NCNFs) is designed and constructed. The experimental results show that a built-in electric field is formed at the interface of CoSe 2 /NiSe 2 Mott-Schottky heterostructure, which promotes the conversion of LiPSs and induces 3D nucleation of Li 2 S. Furthermore, the calculation results of density functional theory clearly reveal high conductivity, adsorption and interfacial charge transfer between CoSe 2 /NiSe 2 Mott-Schottky heterostructure electrocatalyst and LiPSs. As a result, the CoSe 2 /NiSe 2 @NCNFs/S cathode shows a specific capacity of 1050.8 mAh g−1 at 1 C, and maintains excellent cycling performance with a discharge capacity of 735.1 mAh g−1 and a capacity decay of 0.003 % per cycle over 1000 cycles. This work designed a Mott-Schottky heterostructure electrocatalyst to strengthen the adsorption and conversion of LiPSs and induce 3D nucleation of Li 2 S, providing a new idea for high-performance Li-S batteries. [ABSTRACT FROM AUTHOR]

The study is aimed at observing the influence of microribonucleic acid- (miRNA-) 30a-50p on the pulmonary fibrosis in mice with Streptococcus pneumoniae infection through the regulation of autophagy by Beclin-1. Specific pathogen-free mice were instilled with Streptococcus pneumoniae through the trachea to establish the pulmonary fibrosis model. Then, they were divided into the miRNA-30a-50p mimics group (mimics group, n = 10) and miRNA-30a-5p inhibitors group (inhibitors group, n = 10), with the control group (n = 10) also set. Pulmonary tissue wet weight/dry weight (W/D) was detected. The content of tumor necrosis factor-α (TNF-α), interleukin- (IL-) 6, and myeloperoxidase (MPO) was determined using enzyme-linked immunosorbent assay (ELISA). Besides, the changes in the pulmonary function index dynamic lung compliance (Cdyn), plateau pressure (Pplat), and peak airway pressure (Ppeak) were monitored, and the gene and protein expression levels were measured via quantitative PCR (qPCR) and Western blotting. The expression level of miRNA-30a-5p was substantially raised in the mimics group (p < 0.05), but extremely low in the inhibitors group (p < 0.05). The mimics group had obviously raised levels of serum aminotransferase (AST), glutamic-pyruvic transaminase (GPT), alkaline phosphatase (ALP), and pulmonary tissue W/D (p < 0.05). Additionally, the expression levels of TNF-α, IL-6, and MPO were notably elevated in the mimics group, while their expression levels showed the opposite conditions in the inhibitors group (p < 0.05). According to the HE staining results, the inhibitors group had arranged orderly cells, while the mimics group exhibited lung injury, pulmonary edema, severe inflammatory response, and alveolar congestion. In the inhibitors group, Cdyn was remarkably elevated, but Pplat and Ppeak declined considerably (p < 0.05). Besides, the inhibitors group exhibited elevated messenger RNA (mRNA) levels of Beclin-1 and LC3, lowered mRNA levels of α-SMA and p62, a raised protein level of Beclin-1, and a markedly decreased protein level of p62 (p < 0.05). Silencing miRNA-30a-5p expression can promote the expression of Beclin-1 to accelerate the occurrence of autophagy, thereby treating pulmonary fibrosis in mice with Streptococcus pneumoniae infection. [ABSTRACT FROM AUTHOR]