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Summary Twisted graphene-based homo- and heterostructures, consisting of two-dimensional (2D) layered materials with a twist angle (θ), have attracted growing interest due to their unique twist-angle-dependent electronic properties. This novel twist-angle degree of freedom enables the in-depth exploration of quantum phases of matter, and intense observation of strongly correlated phenomena, including superconductivity, Mott insulators, correlated Chern bands, and ferromagnetism, emerging in succession, profits from the steady improvement of fabrication techniques. This timely review summarizes the latest breakthroughs in graphene-based twistronics and technical advances in precisely manifesting the twist angle. The perspectives and challenges of designing and improving 2D twistronic devices are also provided, attempting to offer some useful understanding and guidelines for experimentalists and theorists to explore desired exotic properties and boost practical twistronic applications.

Natural gas pipeline construction is developing rapidly worldwide to meet the needs of international and do-mestic energy transportation. Meanwhile, leakage accidents occur to natural gas pipelines frequently due to mechanical failure, personal operation errors, etc., and induce huge economic property loss, environmental damages, and even casualties. However, few models have been developed to describe the evolution process of natural gas pipeline leakage accidents (NGPLA) and assess their corresponding consequences and influencing factors quantitatively. Therefore, this study aims to propose a comprehensive risk analysis model, named EDIB (ET-DEMATEL-ISM-BN) model, which can be employed to analyze the accident evolution process of NGPLA and conduct probabilistic risk assessments of NGPLA with the consideration of multiple influencing factors. In the proposed integrated model, event tree analysis (ET) is employed to analyze the evolution process of NGPLA before the influencing factors of accident evolution can be identified with the help of accident reports. Then, the combination of DEMATEL (Decision-making Trial and Evaluation Laboratory) and ISM (Interpretative Structural Modeling) is used to determine the relationship among accident evolution events of NGPLA and obtain a hier-archical network, which can be employed to support the construction of a Bayesian network (BN) model. The prior conditional probabilities of the BN model were determined based on the data analysis of 773 accident reports or expert judgment with the help of the Dempster-Shafer evidence theory. Finally, the developed BN model was used to conduct accident evolution scenario analysis and influencing factor sensitivity analysis with respect to secondary accidents (fire, vapor cloud explosion, and asphyxia or poisoning). The results show that ignition is the most critical influencing factor leading to secondary accidents. The occurrence time and occur-rence location of NGPLA mainly affect the efficiency of emergency response and further influence the accident consequence. Meanwhile, the weight ranking of economic loss, environmental influence, and casualties on social influence is determined with respect to NGPLAs.

Although fruit expansion during ripening has been extensively studied, the structural and metabolic mechanisms remain largely unknown. Here, we report the critical roles of cell separation and cell wall metabolism in the coordinated regulation of fruit expansion in Fragaria vesca. Anatomical observations indicated that a syndrome of cell separation occurred from the very earliest stage of fruit set. Cell separation led to an increase in apoplastic space, and the time course of this increase coincided with the period of fruit development and ripening. Moreover, massive cellulose disassembly occurred when cells were fully separated, which coincided with the expansion of cell and fruit volume. Consistent with the anatomical observations, both histochemistry and composition analysis indicated correlations between cell separation and the cell wall metabolism. These observations suggest that cell separation, cell elongation and cell wall disassembly occur simultaneously during fruit ripening in Fragaria vesca.

A metal-free photocatalytic oxidative decarboxylation reaction at room temperature was developed for the synthesis of aromatic aldehydes and ketones from the corresponding arylacetic acids. The reaction was realized under blue-light irradiation by adding 1 mol% of 4CzIPN as photocatalyst and air as oxidant. This reaction represents a novel decarboxylation of a sp3-hybridized carboxylic acids without traditional heating, additional oxidants, and metal reagents under mild conditions.

The explosion characteristics and influential factors of suspended calcium carbide (CaC2) dust were studied using a 20-L spherical vessel. Acetylene (C2H2) and calcium hydroxide (Ca(OH)2) are the reaction products of CaC2 and water. Therefore, C2H2/Ca(OH)2 mixture was used as the reference sample in the experiment. Experimental results showed that the water content in the environment (air relative humidity and external water drops) had significant impacts on CaC2 dust explosion. The explosibility of CaC2 dust enhanced with the increasing air relative humidity In the experiments, CaC2 dust and dry water were equally proportioned when the value of stoichiometric ratio R was 1. When the concentration of hybrid CaC2/dry water increased, the value of Pex of CaC2/dry water explosion rose first and then stabilized at 0.74 MPa, and the value of (dP/dt)ex showed a trend of rising first and then declining after reaching the maximum value of 238.25 MPa s−1. Pex and (dP/dt)ex of pure C2H2 explosion and C2H2/Ca(OH)2 hybrid explosion increased at the early stage and then decreased for the increasing C2H2 content. Pex and (dP/dt)ex of the three samples increased in the following order: hybrid CaC2/dry water

The collection of many environmental pollutants from road dust is harmful to living things and their surroundings. Previous studies have confirmed that road dust affects plant pigmentation, pollination, and biochemical properties. However, there are no comprehensive studies on multi-level dust pollution levels and multifaceted physiological properties of plants, and more importantly, there are no studies on atmospheric dust pollution monitors. In this experiment, the effect of road dust on the morphology and biochemistry of Salvia guaranitica St.Hil.was investigated by simulated deposition of different amounts of dust, and the changes of their physiological morphology under different pollution levels were also explored. A control group CK (0.00 g/plant), four experimental groups S1 (0.015 g/plant), S2 (0.030 g/plant), S3 (0.045 g/plant) and S4 (0.060 g/plant) were sprayed with the same dust samples every other day for 30 days. It was found that after 30 days of dust exposure, different degrees of morphological changes and damage occurred in Salvia. The different pollution levels also resulted in different degrees of biochemical characteristics of Salvia. With the increase of pollution, chlorophyll content, photosynthetic and evaporation rates decreased significantly, but the activity of SOD and the content of MDA increased significantly in different experimental groups. Especially, the experiments also revealed that severe road dust pollution caused damage and deformation to stomata, as well as a significant reduction in stomatal and glandular density. In addition, the regression curves of the different physiological responses of Salvia to road dust can be used as a preliminary basis for plant monitoring of dust pollution degrees, thus provided a scientific basis for the use of plant biomonitors in the field of pollution biology.