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The pressed sleeve connection is a new type of connection technique reported in China recently. To explore the possibility of combining the advantages of pressed sleeve connections and recycled aggregate concrete (RAC) in precast concrete, the seismic performance of precast shear walls with pressed sleeves and recycled fine aggregate (RFA) concrete was investigated through a thorough experimental programme. A total of seven precast shear wall specimens and one cast‐in‐situ specimen were fabricated and tested under lateral cyclic loading, considering the effects of the aspect ratio, the axial compression ratio, and the RFA content. The failure modes, hysteretic behavior, bearing capacity, energy dissipation, stiffness and shear distortion of the specimens, as well as the strains of the steels, were reported and discussed. The test results demonstrated that the pressed sleeve connections were capable of transmitting both tensile and compressive forces between reinforcements, and the precast shear walls with pressed sleeve connections exhibited the same hysteresis behavior, strengths, ductility coefficient and energy dissipation capacity as the cast‐in‐situ counterpart. Moreover, the seismic behavior of the precast specimens with the RFA content of 30% was almost the same as those with natural aggregate concrete (NAC). The increase in the axial compression ratio and aspect ratio led to higher peak loads of the precast shear walls. Finally, existing design methods of ordinary reinforced concrete shear walls were evaluated for their application to the design of precast RFA concrete shear walls with pressed sleeves. Overall, the evaluation results revealed that the examined design methods offer generally accurate strength predictions for the proposed shear walls. [ABSTRACT FROM AUTHOR]

[Display omitted] • Short-term composting for preparing oyster mushroom cultivation was performed. • Variation of physicochemical properties led to succession of microbial communities. • Composting bacteria demonstrated much higher abundance than fungi. • Firmicutes, Actinobacteriota, and Proteobacteria were the dominant bacterial phyla. • Carbohydrate metabolism and amino acid metabolism were the main metabolic pathways. Short-term composting of raw materials for preparing oyster mushroom cultivation media is widely used in China, and its microbial mechanism needs to be further studied. 11-days' peach sawdust-based composting was performed to evaluate material conversion and microbial succession using physicochemical analysis and 16S rRNA and ITS sequencing. Composting bacteria demonstrated much higher abundance than fungi. Firmicutes, Actinobacteriota, and Proteobacteria were the dominant bacterial phyla, while most of fungal species belonged to Ascomycota. Moisture was the key factor at the beginning, while total nitrogen, temperature, and lignin became main influencing factors for composting maturity. Actinobacteriota, Firmicutes, and Proteobacteria of bacterial phyla, Eurotiomycetes and Sordariomycetes of fungal classes involved in lignocellulosic degradation. Bacterial function prediction analysis showed that carbohydrate metabolism and amino acid metabolism were the main metabolic pathways. These results confer a better understanding of material and microbial succession during short-term composting and also provide valuable utilization in mushroom industry. [ABSTRACT FROM AUTHOR]

Agaricus bisporus is in general cultivated on wheat and rice straw in China. However, millet straw is a potential alternative resource for Agaricus bisporus cultivation, but this has hardly been studied. In the present study, the feasibility of millet straw based mushroom production was analyzed by three successive trials. Mature compost demonstrated high quality with total nitrogen, pH, and C/N ratio of 2.0%, 7.5, and 18:1 respectively, which was suitable for mushroom mycelia growth. During composting, 47-50% of cellulose, 63-65% of hemicellulose, and 8-17% lignin were degraded, while 22-27% of cellulose, 14-16% of hemicellulose, and 15-21% of lignin were consumed by A. bisporus mycelia during cultivation. The highest FPUase and CMCase were observed during mushroom flushes. Endo-xylanase had the key role in hemicellulose degradation with high enzyme activity during cultivation stages. Laccase participated in lignin degradation with the highest enzyme activity in Pinning stage followed by a sharp decline at the first flush. Yield was up to 20 kg/m 2 , as this is similar to growth on wheat straw, this shows that millet straw is an effective resource for mushroom cultivation. Actinobacteria, Bacteroidetes, Chloroflexi, Deinococcus-Thermus, Firmicutes, and Proteobacteria were the dominant phyla, based on 16S rRNA gene sequencing during composting. The key environmental factors dominating bacterial communities of the samples were determined to be pH value, cellulose content, and hemicellulose content for prewetting and premixed phase of basic mixture (P0); moisture content for phase I (PI); and nitrogen content, lignin content, and ash content for phase II (PII), respectively.