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Reactions on electrocatalytic interfaces often involve multiple processes, including the diffusion, adsorption, and conversion of reaction species and the interaction between reactants and electrocatalysts. Generally, these processes are constantly changing rather than being in a steady state. Recently, dynamic evolution processes on electrocatalytic interfaces have attracted increasing attention owing to their significant roles in catalytic reaction kinetics. In this review, we aim to provide insights into the dynamic evolution processes in electrocatalysis to emphasize the importance of unsteady-state processes in electrocatalysis. Specifically, the dynamic structure evolution of electrocatalysts, methods for the characterization of the dynamic evolution and the strategies for the regulation of the dynamic evolution for improving electrocatalytic performance are summarized. Finally, the conclusion and outlook on the research on dynamic evolution processes in electrocatalysis are presented. It is hoped that this review will provide a deeper understanding of dynamic evolution in electrocatalysis, and studies of electrocatalytic reaction processes and kinetics on the unsteady-state microscopic spatial and temporal scales will be given more attention. [ABSTRACT FROM AUTHOR]

Electrocatalysts are the key components of electrochemical energy storage and conversion devices. High performance electrocatalysts can effectively reduce the energy barrier of the chemical reactions, thereby improving the conversion efficiency of energy devices. The electrocatalytic reaction mainly experiences adsorption and desorption of molecules (reactants, intermediates and products) on a catalyst surface, accompanied by charge transfer processes. Therefore, surface control of electrocatalysts plays a pivotal role in catalyst design and optimization. In recent years, many studies have revealed that the rational design and regulation of a defect structure can result in rearrangement of the atomic structure on the catalyst surface, thereby efficaciously promoting the electrocatalytic performance. However, the relationship between defects and catalytic properties still remains to be understood. In this review, the types of defects, synthesis methods and characterization techniques are comprehensively summarized, and then the intrinsic relationship between defects and electrocatalytic performance is discussed. Moreover, the application and development of defects are reviewed in detail. Finally, the challenges existing in defective electrocatalysts are summarized and prospected, and the future research direction is also suggested. We hope that this review will provide some principal guidance and reference for researchers engaged in defect and catalysis research, better help researchers understand the research status and development trends in the field of defects and catalysis, and expand the application of high-performance defective electrocatalysts to the field of electrocatalytic engineering. [ABSTRACT FROM AUTHOR]

Real-time and accurate predictive maintenance of industrial equipment is fundamental for ensuring the safety and stability of advanced manufacturing processes. Current fault diagnosis methods based on data mining rely on a large number of labeled samples, and obtaining sufficient labeled data for diagnosing industrial equipment faults is challenging. Meta-learning can achieve the diagnosis of few-shot samples to a certain extent, but the effect is not ideal. Semi-supervision can effectively leverage a large number of unlabeled samples, which is of great practical significance for handling scenarios involving limited labeled samples. However, noise interference can occur when unlabeled samples appear that do not belong to known categories. Therefore, this study proposes adaptive semi-supervised meta-learning networks (ASMNs) for noisy few-shot gearbox fault diagnosis. Firstly, a residual network with a Morlet Wavelet layer is used to extract signal features. Next, sample-level attention is defined to select unlabeled samples that are more similar to labeled sample prototypes, thereby reducing the influence of noisy samples. The adaptive metric is used to obtain the relational distance functions of labeled samples and unlabeled samples. Adaptive semi-supervised ASMNs uses unlabeled data to refine prototypes for better fault diagnosis. The effectiveness and anti-noise performance of the proposed method are verified by using two gearbox datasets with various few-shot noise scenarios. [ABSTRACT FROM AUTHOR]

Background: The post COVID-19 health condition of Chinese residents infected with Omicron is not clear after the change of epidemic prevention policies. This study aimed to clarify the epidemiology and associated factors about health status of rehabilitation patients. Methods: A quick questionnaire study based on C19-YRSm was conducted in mainland China through internet from May 1, 2023, to May 7, 2023. Chinese native speakers infected with Omicron variant agreed to participate were included. Persisting symptom and living habits were simultaneously inquired. Logistic regression analysis was used to identify the associated factors. Results: In this study 753 individuals were included. Of whom 57.90% were males, 89.38% did not seek medical service, 99.47% recovered within less than 120 days. Breathlessness (47.68%), cognitive impairment (44.89%), Anxiety/mood changes (33.20%), pain/discomfort (32.94%), fatigue or tiredness not improved by rest (32.27%) and post-exertional malaise (30.01%) were the top reported key symptoms. Less than 10% respondents reported functional limitations. The prevalence of fever was reported greater than that of other symptoms, with dry eyes at 14.87%, appetite change at 14.34%, and hair loss at 12.22%. Middle age (OR: 2.353, 95%CI: 1.171 ~ 4.729), underlying diseases (OR: 2.293, 95%CI: 1.216 ~ 4.324), severe key symptom (OR: 6.168, 95%CI: 1.376 ~ 27.642) and at least one other symptom (OR: 1.847, 95%CI: 1.225 ~ 2.718)during the recovery were the risk factors of poor overall health after infection (current overall health score <8; 74.10%), while daily exercise in recovery period (OR: 0.457, 95%CI: 0.229 ~ 0.913), a low-fat diet (OR: 0.600, 95%CI: 0.401 ~ 0.898) and the recovery time from 2 to 4 months (OR: 0.639, 95%CI: 0.445 ~ 0.918) were the protective factors. Conclusion: This is the first time to use the C19-YRSm scale to evaluate the health status in China. The study revealed prevalence of persistent symptoms within 120 days after Omicron onset. [ABSTRACT FROM AUTHOR]

Using the electrochemical polyol oxidation reaction (POR) to produce formic acid over nickel-based oxides/hydroxides (NiO x H y) is an attractive strategy for the electrochemical upgrading of biomass-derived polyols. The key step in the POR, i.e. the cleavage of the C–C bond, depends on an oxygen-vacancy-induced mechanism. However, a high-energy oxygen vacancy is usually ineffective for Schottky-type oxygen-vacancy-rich β-Ni(OH)2 (VSO-β-Ni(OH)2). As a result, both β-Ni(OH)2 and VSO-β-Ni(OH)2 cannot continuously catalyze oxygen-vacancy-induced C–C bond cleavage during PORs. Here, we report a strategy of oxygen-vacancy-filling with sulfur to synthesize a β-Ni(OH)2 (S-VO-β-Ni(OH)2) catalyst, whose oxygen vacancies are protected by filling with sulfur atoms. During PORs over S-VO-β-Ni(OH)2, the pre-electrooxidation-induced loss of sulfur and structural self-reconstruction cause the in-situ generation of stable Frenkel-type oxygen vacancies for activating vacancy-induced C–C bond cleavage, thus leading to excellent POR performances. This work provides an intelligent approach for guaranteeing the sustaining action of the oxygen-vacancy-induced catalytic mechanism in electrooxidation reactions. [ABSTRACT FROM AUTHOR]

Ammonia (NH3) is a crucial industrial raw material, but the traditional Haber-Bosch process is energy-intensive and highly polluting. Electrochemical methods for synthesizing ammonia using nitric oxide (NO) as a precursor offer the advantages of operating under ambient conditions and achieving both NO reduction and resource utilization. Defect engineering enhances electrocatalytic performance by modulating electronic structures and coordination environments. In this brief review, the catalytic reaction mechanism of electrocatalytic NO reduction to NH3 is elucidated, with a focus on synthesis strategies involving vacancy defects and doping defects. From this perspective, the latest advances in various catalytic reduction systems for nitric oxide reduction reaction (NORR) are summarized and synthesized. Finally, the research prospects for NO reduction to NH3 are discussed. [ABSTRACT FROM AUTHOR]

The experiment aimed to investigate the impact of substituting corn with fermented sweet potato potato on the growth performance, serum biochemical indexes, immune indexes, and intestinal morphology of yellow-feathered broilers. A total of 360 one-day-old yellow-feathered broilers were randomly divided into four groups, with six replicates in each group, and 15 broilers in each replicate. The broilers in control group were fed a basal diet. Groups I, II, and III were fed diets with 1%, 3%, and 5% fermented sweet potato pomace substituting corn, respectively, from 1 to 21 days of age, and 5%, 8%, and 10% from 22 to 42 days and 43 to 70 days of age, respectively. The trial lasted for 70 days. The results showed that substituting corn with fermented sweet potato pomace did not significantly affect the average daily weight gain, average daily feed intake, and feed conversion ratio of the yellow-feathered broilers (P>0.05). Compared to the control group, the levels of serum high-density lipoprotein cholesterol (HDL-C), immunoglobulin A (IgA), immunoglobulin G (IgG), interleukin-2 (IL-2), and interleukin-6 (IL-6) in groups I and II were significantly increased (P<0.05). At 21 days of age, the villus height and crypt depth of the duodenum in group I were significantly reduced (P<0.05), while the crypt depth in the ileum was significantly increased (P<0.05), and the villus height to crypt depth ratio (V/C) in the ileum of groups I and III were significantly decreased (P<0.05). At 42 days of age, the villus height of the duodenum and jejunum and crypt depth of the jejunum in group III were significantly reduced (P<0.05), the V/C of the duodenum in group I was significantly increased (P<0.05), and the villus height of the ileum in groups I and II were significantly increased (P<0.05). At 70 days of age, the villus height and V/C of the duodenum in groups I and II were significantly increased (P<0.05), the crypt depth was significantly reduced (P<0.05), and the villus height and V/C of the jejunum in group II were significantly increased (P<0.05). The study indicates that adding fermented sweet potato pomace to the diet as a substitute for corn can improve the serum immune indicators and intestinal tissue morphology of yellow-feathered broilers, and the optimal supplemental level is 5% at 1 to 21 days of age and 8% at 22 to 70 days of age. [ABSTRACT FROM AUTHOR]