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In this work, the two-dimensional fluid models for two types of inductively coupled plasma, Ar/O2 and Ar/SF6, are numerically solved by the finite element method. Four interesting phenomena revealed by the simulations are reported: (1) comet-shaped and semi-circle-shaped structures in Ar/O2 and Ar/SF6 plasmas, respectively; (2) blue sheaths that surround the two structures; (3) the collapse and dispersion of semi-circle-shaped structures of certain Ar/SF6 plasma cations and anions when they are observed separately; and (4) the rebuilding of coagulated structures by minor cations in the Ar/SF6 plasma at the discharge center. From the simulation detail, it was found that the cooperation of free diffusion and negative chemical sources creates the coagulated structure of anions, and the self-coagulation theory is therefore built. The advective and ambipolar types of self-coagulation are put forth to explain the co-existence of blue sheath and internal neutral plasma, among which the advective type of self-coagulation extends the Bohm’s sheath theory of cations to anions, and the ambipolar type of self-coagulation originates from the idea of the ambipolar diffusion process, and it updates the recognition of people about the plasma collective interaction. During the ambipolar self-coagulation, each type of Ar/SF6 plasma cations and anions is self-coagulated, and the coagulated plasma species are then modeled as mass-point type (or point-charge type, more precisely). When the charge amounts of two point-charge models of plasma species with the same charge type are equal, the expelling effect caused by the Coulomb’s force of them leads to the collapse or dispersal of heavily coagulated species. The simulation shows that the lighter the species is, the easier it self-coagulates and the more difficult its coagulation is broken, which implies the inertia effect of density quantity. Moreover, the collapse of cation coagulation creates the spatially dispersed charge cloud that is not shielded into the Debye’s length, which indicates the anti-collective behavior of electronegative plasmas when they are self-coagulated. The rebuilt coagulated structure of minor Ar/SF6 plasma species at the discharge center and the weak coagulation of electrons in the periphery of the main coagulated structure that is under the coil are caused by the monopolar and spontaneous (non-advective) type of self-coagulation. The analysis predicts an intensity order of physically driven coagulation force, chemical self-coagulation force, and ambipolar self-coagulation force. The popular coagulated structure of the electronegative ICP sources is urgently needed to validate the experiment.

The dry beach length determines the hydraulic boundary of tailings impoundments and significantly impacts the infiltration line, which is crucial for the tailings dam. A deep learning method utilizing satellite images is presented to recognize the dry beach area and accurately measure the length of dry beaches in tailing ponds. Firstly, satellite images of various tailing ponds were gathered and the collection was enlarged to create a dataset of satellite images of tailing ponds. Then, a deep learning method was created using YOLOv5-seg to identify the dry beach area of tailing ponds from satellite images. The mask of the dry beach region was segmented and contour extraction was then carried out. Finally, the beach crest line was fitted based on the extracted contour. The pixel distance between the beach crest line and the dry beach boundary was measured and then translated into real distance by ground resolution. This paper’s case study compared the calculated length of dry beach with the real length obtained by field monitoring. The results of the case study showed that the minimum error of the method was 2.10%, the maximum error was 3.46%, and the average error was 2.70%, indicating high precision for calculating dry beach length in tailing ponds.

Polycyclic aromatic hydrocarbons (PAHs) are persistent environmental pollutants commonly found in water and sediments, posing significant health risks due to their toxicity, carcinogenicity, and mutagenicity. The stable and sustainable degradation of PAHs has garnered significant attention from researchers. Biological electrochemical systems (BESs) offer a promising approach with advantages in energy efficiency, safety, environmental protection, and long-term operation. This review examines the degradation performance and microbial community dynamics of BESs in the treatment of PAH-contaminated water and sediments. Additionally, the metabolites formed during the degradation process were also summarized. This review summarizes the degradation characteristics of PAH-contaminated water and sediments and aims to guide future research and optimize BESs for effective remediation of PAHs in various environmental settings.

Excessive nitrogen application may adversely impact grain yield and quality of rice. This study aimed to evaluate the impact of several nitrogen-reduction strategies on the grain yield and quality of mechanically transplanted hybrid indica rice. Field experiments were performed in 2020 and 2021 using Yixiangyou2115 and Fyou498. The research investigated variations in grain yield and quality of rice under different nitrogen-reduction strategies, including NR1, balanced N reduction; NR2, N reduction in basal fertilizer; NR3, N reduction in tillering fertilizer; and NR4, N reduction in earing fertilizer, compared to the conventional nitrogen application for high-yield cultivation (CK). Compared to CK, the grain yield of rice decreased by 1.63% to 19.71% under nitrogen-reduction strategies. Relative to NR3 and NR4, NR1 and NR2 exhibited an increase in grain yield ranging from 1.81% to 22.51%, attributed to increases in panicle number (0.61% to 13.19%) and spikelet number per panicle (1.60% to 12.28%). Meanwhile, NR1 and NR2 also had relatively high LAI and dry matter accumulation in rice plants at maturity. Compared to CK, NR1 and NR2 improved the processing quality of rice grain, while NR3 and NR4 resulted in reduced processing quality. The chalkiness rate and chalkiness degree of rice under the NR1, NR3, and NR4 treatments were reduced by 2.97% to 23.73% and 3.35% to 52.49%, respectively, in comparison to CK. Additionally, the NR1 and NR4 treatments were linked to an increase in taste value by 1.44% to 3.66% and gel consistency by 13.87% to 46.01% relative to CK. These findings suggest that balanced nitrogen reduction can maintain a high yield while improving the appearance and eating quality of mechanically transplanted hybrid indica rice. This study offers a theoretical basis for rational nitrogen reduction and high-quality cultivation in rice.

Objective: This study aimed to investigate the effects of overground robot exoskeleton gait training on gait outcomes, balance, and motor function in patients with stroke. Methods: Following the PRISMA guidelines, literature searches were performed in the PubMed, EMBASE, Cochrane Central Register of Controlled Trials, SCOPUS, Ovid-LWW, and RISS databases. A total of 504 articles were identified, of which 19 were included for analysis after application of the inclusion and exclusion criteria. The included literature was qualitatively evaluated using the PEDro scale, while the Egger’s regression, funnel plot, and trim-and-fill methods were applied to assess and adjust for publication bias. Results: The averaged PEDro score was 6.21 points, indicating a high level of methodological quality. In the analysis based on dependent variables, higher effect sizes were observed in the following ascending order: gait speed (g = 0.26), motor function (g = 0.21), gait ability (g = 0.18), Timed Up and Go Test (g = −0.15), gait endurance (g = 0.11), and Berg Balance Scale (g = 0.05). Subgroup analyses further revealed significant differences in Asian populations (g = 0.26), sessions lasting longer than 30 min (g = 0.37), training frequency of three times per week or less (g = 0.38), and training duration of four weeks or less (g = 0.25). Overall, the results of this study indicate that overground robot exoskeleton gait training is effective at improving gait speed in patients with stroke, particularly when the sessions exceed 30 min, are conducted three times or less per week, and last for four weeks or less. Conclusion: our results suggest that training is an effective intervention for patients with stroke, provided that appropriate goal-setting and intensity and overground robot exoskeleton gait are applied.

The subgrade serves as the foundation of road construction, typically involving a significant amount of earthwork during its establishment. However, in coastal and desert areas, soil sources are often scarce. Local soil extraction significantly damages cultivated land, impacting the local ecological environment. Transporting soil over long distances inevitably raises construction costs. Fortunately, these regions often feature abundant fine sand distribution, presenting an opportunity to utilize it as subgrade filler in coastal regions. This review comprehensively introduces the properties of fine sand as a raw material, its engineering applications, and the associated construction technologies. It emphatically discusses the road use characteristics and treatment technology of fine sand filler and puts forward a prospect combining the characteristics and development trends of fine sand so as to provide a new perspective and basic material for the application of fine sand in the subgrade. To foster the adoption of fine sand in subgrade construction, it is recommended to advance research on the evaluation and treatment of fine sand foundations, analyze its suitability and structural behavior as a filler, and refine construction methodologies and quality control measures specific to fine sand subgrades.

Owing to the requirements for high performance and long life, the friction and wear problems of rolling piston type rotary compressors have drawn much attention. Various theoretical models have been developed and improved to reveal the inner state of the compressor and obtain the optimization schemes. However, there remain some disadvantages and research gaps in the corresponding modeling and mixed lubrication analyses, and a comprehensive summary is lacking. To have a better understanding of the research status, this paper reviews the theoretical model development and mixed lubrication analyses of the compressor in the past decades. The determination of compression pressure, the modeling process of moving components, and the key findings are presented in detail. On this basis, some important influencing factors and the problems remaining to be solved are also discussed. This paper provides multifaceted guidance for manufacturers and researchers to conduct further theoretical analysis and optimal design.

With the development of technical requirements, the current challenges faced by bearing materials mainly revolve around high-temperature conditions and the trend towards material lightweighting. Full ceramic bearings are the new candidate due to their excellent properties. This article details the tribological and adsorption performance of chlorophenyl silicone oil (CPSO) as a high-temperature lubricant in ceramic tribological systems (ZrO2, Al2O3, and Si3N4). Among the three ceramic tribological systems, the lubrication performance can be ordered as Si3N4 > Al2O3 > ZrO2, as the wear rates of the ZrO2 and Al2O3 tribo-systems are almost 1135.67 and 283.33 times larger than that of the Si3N4 tribo-system, respectively. The observed results can be explained by the superior adsorption performance of CPSO on a Si3N4 ceramic surface, which was calculated by molecular dynamic simulation. The molecular dynamic simulation results show the adsorption energy of CPSO/Si3N4 is almost 54.09 and 61.18 times higher compared to that on ZrO2 and Al2O3 ceramics. These findings provide experimental and theoretical insights for understanding the lubrication performance of CPSO in a full ceramic tribo-system.

New co-processed excipients comprising lactose (filler and sweetener), microcrystalline cellulose (MCC, filler), and low-substituted hydroxypropyl cellulose (L-HPC, disintegrant and binder) were developed via solvent evaporation for the preparation of metoclopramide orally disintegrating tablets (MCP ODTs). Single-factor and Box–Behnken experimental designs were employed to optimize the formulation. The optimized formulation ratios were water: MCC: lactose (g/g) = 17.26:2.79:4.54:1. The results demonstrated that particles formed by solvent evaporation had superior flowability and compressibility compared to the physical mixture. Tablets compressed with these co-processed excipients exhibited a significantly reduced disintegration time of less than 25 s and achieved complete dissolution within 5 min. Pharmacokinetic studies revealed that MCP ODTs significantly improved Cmax, which was 1.60-fold higher compared to conventional tablets. In summary, the lactose/L-HPC/MCC triple-based co-processed excipients developed in this study are promising and could be successfully utilized in orally disintegrating and fast-release tablets.

Sewage sludge has long been perceived as the bottleneck of wastewater treatment plants in China, restraining the healthy development of sewage treatment for decades. In recent years, pyrolysis as a promising multifunctional platform has attracted increasing interest for converting sludge into valuable resources. However, the generation and presence of pyrolysis tar, one of the key by-products during sludge pyrolysis, limit the wide application of pyrolysis product resources. The efficient and selective conversion of tar is complicated by the inherent complexity of sludge and various pollutants (e.g., N-, S-, and Cl-containing organic pollutants, heavy metals) in pyrolysis products, which may either migrate into tar or be released into the environment, complicating the in-depth treatment of tar and posing environmental risks. This review systematically examines the transformation and migration of tar and related secondary pollutants during sludge pyrolysis in order to optimize the pyrolysis process for resource recovery. We provide an overview of the research progress on tar generation, transformation, and secondary pollutants during pyrolysis; discuss potential control strategies for pollution abatement; and highlight the importance of understanding tar transformation during pyrolysis. Additionally, we offer insights into future development trends and research hotpots in this field. This review aims to deliver valuable information on the mechanism of tar formation, the conversion pathways of secondary pollutants, and corresponding control strategies, thus guiding the design and optimization of sludge pyrolysis processes to achieve higher efficiency and selectivity, with minimal environmental pollution.

In recent years, trade protectionism and unilateralism have prevailed, and countries around the world have imposed restrictions on log exports. It has also become more difficult for China to import wood resources and export deep-processed wood forest products. Based on panel data from 2000 to 2019, this study uses social network analysis to measure the level of the Chinese wood forest product trade network, takes the Chinese free trade agreements (FTAs) as the natural experiment, and uses the multi-stage double-difference method to investigate the impact of the signed FTAs on China’s wood forest product trade. The study finds that the trade network of Chinese wood forest products is becoming increasingly complex, and the central position of China and the Association of Southeast Asian Nations (ASEAN) in the network is increasing year by year. The signing of FTAs has had a significant positive impact on the trade of wood forest products in China and a significant trade creation effect. This finding remains true after conducting the placebo test and propensity score-matched regression control. At the same time, the import of wood forest products in China will have a significant trade transfer effect due to the signing of FTAs, and this will not affect exports. Although FTAs show significant trade creation and trade transfer effects in China’s wood forest product trade, they also increase, to a certain extent, the mismatch of forest resources worldwide.