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Abstract: With customized CFD commercial code FLUENT software, the numerical simulation of the argon flow field of inductively coupled plasma spheroidization system was performed by using κ–ε turbulent model and PISO pressure–velocity coupling algorithm. The injected TiAl alloy powder particle trajectories were simulated by using dispersed particle group trajectory model (DPM), and after passing through the argon flow field the particle collection rates of the powders with different particle sizes were predicted. The results show that the simulation values of the powder collection rates and granulometric parameters of the spheroidized powders are close to the experimental data, which indicates the numerical simulation of the argon flow field and injected TiAl alloy powder particle trajectories of inductively coupled plasma spheroidization system is reliable. [Copyright &y& Elsevier]

• Ethanol yields of SFA1OE were around 0.492 g/g total sugars in different hydrolysates. • Diploid strain SQ-2 displays improved ethanol yield and high temperature resistance. • Contributions of gene SFA1 on ethanol yields were evaluated in various hydrolysates. • SFA1OE with high ethanol yield fits to alkaline-distilled sweet sorghum bagasse. Here, an engineered Saccharomyces cerevisiae strain SFA1OE was constructed by overexpressing SFA1 in a reported WXY70 with effective six-gene clusters. Under simulated maize hydrolysate, SFA1OE produced an ethanol yield of 0.492 g/g total sugars within 48 h. The productivity of SFA1OE was comprehensively evaluated in typical hydrolysates from stalks of maize, sweet sorghum, wheat and Miscanthus. Within 48 h, SFA1OE achieved an ethanol yield of 0.489 g/g total sugars in the optimized hydrolysate of alkaline-distilled sweet sorghum bagasse derived from Advanced Solid-State Fermentation process. By crossing SFA1OE with a DQ1-derived haploid strain, we obtained an evolved diploid strain SQ-2, exhibiting improved ethanol production and thermotolerance. This study demonstrates that overexpressing SFA1 enables efficient fermentation performance in different lignocellulosic hydrolysates, especially in the hydrolysate of alkaline-distilled sweet sorghum bagasse. The increased cellulosic bioethanol production of SFA1OE provides a promising platform for efficient biorefineries. [ABSTRACT FROM AUTHOR]

Abstract: Micro-fine high Nb containing TiAl alloyed powders were prepared by using fluidized bed jet milling from the pre-crushed Ti–45Al–8.5Nb–0.2W–0.2B–0.02Y(at.%) ingot. The effects of process parameters on the powder characteristics were investigated. The results show that the particle characteristics are mainly determined by classifier frequency. At or above 5600rpm, the ground powders are composed of coarse block-shaped particles and finer flaky debris, with particle number-average diameter lower than 18μm. With the increase of classifier frequency and the decrease of grinding gas pressure, the amount of flaky debris formed under abrasion mechanism gradually increases, which causes the obvious decrease of the powder number-average diameter, distribution uniformity, and sphericity degree. With the classifier frequency of 8400rpm and grinding gas pressure of 0.55MPa, the obtained powders possess the minimum particle size of 5.32μm, with a uniformity level of 0.38 and a Wadell's sphericity factor of 0.820. [Copyright &y& Elsevier]

[Display omitted] • Aging in soil lead the surface of PS-MP being wrapped by soil particles. • The wrapping effects of soil particles induced the formation of protective layer. • Protective layer increased the particle size of PS-MP and decreased its ingestion. • The aging of PS-MP in the soil decreased its toxicity to earthworms. The recent discovery of microplastics contaminants in most ecosystems has raised major health issues, yet knowledge on their impact on soil organisms is limited, especially their toxicity evolution with aging. Herein, the toxicity of polystyrene microplastic (PS-MP) to earthworm (Eisenia fetida) along with aging was investigated. Results showed that the 28 d-LC 50 (50% lethal concentration) of PS-MP was 25.67 g kg−1, whereas that increased to 96.47 g kg−1 after PS-MP initially aged in soil for 28 days, indicating the toxicity of PS-MP decreased with aging. Laser scanning confocal microscope and scanning electron microscope (SEM) found that the toxicity of PS-MP to earthworm may be due to the ingestion of PS-MP by earthworms and the physical damage (e.g., epidermis abrasion and setae loss) of PS-MP to earthworms. Similarly, the levels of reactive oxygen species, antioxidant enzyme activities and malondialdehyde content increased with PS-MP concentrations from 0.1 to 1.5 g kg−1, but decreased with aging from 7 to 28 days. The integrated biomarker response index also confirmed that the toxicity of PS-MP decreased with aging. SEM found that PS-MP were progressively covered by soil particles during soil aging, inducing the formation of protective layer and increasing the particle size of PS-MP, which prevented direct contact with earthworms and decreased the ingestion of PS-MP, in turn decreased PS-MP toxicity. Overall, our study provides valuable insights for elucidating the effect of aging on the toxicity of microplastics. [ABSTRACT FROM AUTHOR]

• •The identification and determination methods of biochar-PFRs were outlined. • •The redox activity of biochar-PFRs was discussed. • •The consumption and generation mechanism of biochar-PFRs were summarized in detail. • •The dilemma of evaluating the redox activity of biochar-PFRs was pointed out. • •Strategies of determining the redox activity of biochar-PFRs were proposed. Biochar-bound persistent free radicals (biochar-PFRs) attract much attention because they can directly or indirectly mediate the transformation of contaminants in large-scale wastewater treatment processes. Despite this, a comprehensive top-down understanding of the redox activity of biochar-PFRs, particularly consumption and regeneration mechanisms, as well as challenges in redox activity assessment, is still lacking. To tackle this challenge, this review outlines the identification and determination methods of biochar-PFRs, which serve as a prerequisite for assessing the redox activity of biochar-PFRs. Recent developments concerning biochar-PFRs are discussed, with a main emphasis on the reaction mechanisms (both non-free radical and free radical pathways) and their effectiveness in removing contaminants. Importantly, the review delves into the mechanism of biochar-PFRs regeneration, triggered by metal cations, reactive oxygen species, and ultraviolet radiations. Furthermore, this review thoroughly explores the dilemma in appraising the redox activity of biochar-PFRs. Components with unpaired electrons (particular defects and metal ions) interfere with biochar-PFRs signals in electron paramagnetic resonance spectra. Scavengers and extractants of biochar-PFRs also inevitably modify the active ingredients of biochar. Based on these analyses, a practical strategy is proposed to precisely determine the redox activity of biochar-PFRs. Finally, the review concludes by presenting current gaps in knowledge and offering suggestions for future research. This comprehensive examination aims to provide new and significant insights into the redox activity of biochar-PFRs. [Display omitted] [ABSTRACT FROM AUTHOR]