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Forest microclimates can contrast substantially from the macroclimate outside forests. These microclimates regulate understory biodiversity and ecosystem functions. Studies have quantified the global patterns and driving factors of forest understory temperature offsets, but data from China were almost missing, making the global assessment incomplete. To fill this knowledge gap, we quantitatively synthesized 494 paired observations from China extracted from 91 publications to quantify mean (Tmean), maximum (Tmax) and minimum temperature offsets (Tmin). Results showed that (1) forest canopies significantly buffered understory Tmean and Tmax against macroclimatic temperature, with average offsets of 1.0 and 1.5°C, respectively, while understory Tmin offsets were not significantly different from zero; (2) forest type (broadleaved, mixed, vs. coniferous) and forest location (rural vs. urban) did not affect Tmean, Tmax or Tmin offsets, but climate zone and season showed significant impacts; and (3) macroclimatic temperature, wind speed, tree height and canopy density also impacted temperature offsets, although their effects varied among Tmean, Tmax and Tmin. Our results complement the global assessment of forest buffering capacity, and reiterate the necessity for incorporating microclimatic variability into future bioclimatic modelling of species demography and distributions. [ABSTRACT FROM AUTHOR]

Mining causes severe damage to soil ecosystems. Vegetation restoration in abandoned mine areas is an inevitable requirement for sustainable development. Soil microbes, as the most active component of soil organic matter, play a crucial role in the transformation of carbon, nitrogen, phosphorus, and other elements. They are often used as indicators to assess the extent of vegetation restoration in ecologically fragile areas. However, the impacts of vegetation restoration on soil microbial community structure in mining areas at the global scale remains largely un-known. Based on 310 paired observations from 44 papers, we employed the meta-analysis approach to examine the influence of vegetation restoration on soil microbial abundance and biomass in mining area. The results indicated that vegetation restoration significantly promotes soil microbial biomass in mining areas. In comparison to bare soil, vegetation restoration leads to a significant 95.1% increase in soil microbial biomass carbon and a 87.8% increase in soil microbial biomass nitrogen. The abundance of soil bacteria, fungi, and actinomycetes are significantly increased by 1005.4%, 472.4%, and 177.7%, respectively. Among various vegetation restoration types, the exclusive planting of trees exhibits the most pronounced promotion effect on soil microbial biomass and population, which results in a significant increase of 540.3% in soil fungi and 104.5% in actinomycetes, along with a respective enhancement of 110.3% and 106.4% in microbial biomass carbon and nitrogen. Model selection results revealed that soil saturated water content and vegetation restoration history contribute most significantly to the abundance of soil bacteria and fungi. Soil available nitrogen has the most significant impact on the abundance of actinomycetes and microbial biomass carbon, while soil available phosphorus emerges as a crucial factor affecting microbial biomass nitrogen. This research could contribute to understanding the relationship between vegetation restoration and the structure of soil microbial communities in mining areas, and providing scientific support for determining appropriate vegetation restoration types in mining areas. [ABSTRACT FROM AUTHOR]

Pulverized semi-coke was employed as raw material to prepare activated carbon via steam activation and evaluated as a CO2 adsorbent. The effects of the preparation parameters including demineralization, activation temperature, activation time and steam flow on the structure and performance of the synthesized activated carbon were investigated. It was found that the microporous structure of activated carbon was greatly influenced by demineralization order and activation conditions. Demineralization before activation significantly increased the microporous structure of the activated carbon, which was ascribed to the removal of the inorganic fraction. Compared to the commercial activated carbon, activated carbon obtained by employing 150 mL/min steam to treat the demineralized pulverized semi-coke at 700 °C for 70 min possessed a higher CO2/N2 selectivity of 34.4 and good cyclic performance, which was due to its narrow microporosity of 0.55 nm. Furthermore, it was proved that a pore size of smaller than 1 nm is favorable for CO2 sorption. [ABSTRACT FROM AUTHOR]

A general, practical, and environmentally friendly protocol to synthesize 1,2,3‐trisubstituted 4‐quinolones from readily available ynones and sulfonamides was developed. The construction of one C−C bond and two C−N bonds via cleavage of one N−S, one C−S, and one C−X (X=F, Cl, Br, O) bond is achieved under transition‐metal‐free conditions in one step. This transformation generates 1 equiv. of sulfur dioxide and 1 equiv. of hydrogen halide as the byproducts. The broad substrate scope and functional group tolerance are demonstrated by 52 examples of 1,2,3‐trisubstituted 4‐quinolones. A preliminary mechanistic study supports a sequential Michael addition/Smiles rearrangement/N‐arylation reaction pathway. [ABSTRACT FROM AUTHOR]

A detailed cutting tool design approach, tool shape-performance-application integrated design (TSpaiD) approach, is proposed to address the cutting tool specification trend. Based on the concept, a three-tier architecture, consisting of shape, performance and application layers, is developed to optimise cutting tools and machine conditions together. Within the context, multi-objective optimisation combining linear weight method is employed to address the machining requirements which are represented by each individual objective. Also, the cutting tool and the machining conditions are described by feasible set bounded by machining requirements and manufacturing resource. To implement the method, a software prototype is developed, and then a numeral validation, a genetic algorithm based optimisation, is given. [ABSTRACT FROM AUTHOR]

AbstractTo improve the uniformity of the hot air drying quality for stacked flake materials, a heat and mass transfer study of stacked flake materials drying process based on multi-physical field coupling is carried out. A numerical simulation model of the stacked flake materials is developed based on the multi-physical field coupling theory, and the accuracy of the numerical simulation model is verified by the bidirectional alternating hot air drying test bed. The segmented hot air drying method is used to analyze the influence mechanism of single airflow direction and alternate airflow direction on the heat and mass transfer for stacked flake materials, and the optimization of drying parameters is studied. The results indicate that a single airflow direction may cause excessive drying, and the uneven stacking density significantly affects the drying quality. The increase of air flow direction change number will lead to the improvement of drying uniformity and moisture content of drying results, and at the same time, the flake material absorbs moisture significantly after changing the air flow direction. By adopting the down-down-up-up airflow direction and optimizing the parameters, the moisture content uniformity of the drying results is improved by 19%, while energy consumption is reduced. [ABSTRACT FROM AUTHOR]