Suchergebnisse

AbstractThe coal mine production industry is a complex sociotechnical system with interactive relationships among several risk factors. Currently, causation analysis of gas explosion accidents is mainly focused on the aspects of human error and equipment fault, while neglecting the interactive relationships among risk factors. A new method is proposed through risk coupling. First, the meaning ofrisk coupling of a gas explosionis defined, and types of risk coupling are classified. Next, the coupled relationship and coupled effects among risk factors are explored through combining the interpretative structural modeling (ISM) and the NK model. Twenty‐eight representative risk factors and 16 coupled types of risk factors are obtained through analysis of 332 gas explosion accidents in coal mines in China. Through the application of the combined ISM–NK model, an eight‐level hierarchical model of risk coupling of a gas explosion accident is established, and the coupled degrees of different types of risk coupling are assessed. The hierarchical model reveals that two of the 28 risk factors, such as state policies, laws, and regulations, are the root risk factors for gas explosions; nine of the 28 risk factors, such as flame from blasting, electric spark, and local gas accumulation, are direct causes of gas explosions; whereas 17 of the risk factors, such as three‐violation actions, ventilation system, and safety management, are indirect ones. A quantitative analysis of the NK model shows that the probability of gas explosion increases with the increasing number of risk factors. Compared with subjective risk factors, objective risk factors have a higher probability of causing gas explosion because of risk coupling.

AbstractDietary exposure to heavy metals and metalloids [metal(loid)s] deserves increased attention; however, there is a lack of a comprehensive understanding of the risks of dietary exposure from multi-type food intake and multi-metal(loid) exposure using a bioaccessibility-corrected method. Here, we determined the concentration and bioaccessibility of six toxic metal(loid)s in six major food groups in an industrial city with intensive smelting activity. By incorporating children's dietary patterns, the probability distribution of health risks from dietary metal(loid)s exposure was assessed. Marked differences were observed in the dietary exposure characteristics within metal(loid)s and major food groups. Cereal and vegetables were the major food groups local children intake. Cereals, meat, beans, and aquatic products had the highest concentrations of Cu and Cd, Pb and Cr, Ni, and As, respectively. Generally, meat, eggs, and aquatic products exhibited higher bioaccessibility than cereals, beans, and vegetables. The bioaccessibility of metal(loid)s decreased in the following order: Pb > Cr > Cu > Ni > As > Cd. For non-carcinogenic risks, the average hazard index was 7.3, with 99.6% exceeding acceptable levels. Arsenic was the dominant risk element and aquatic product was the main risk source. The aggregated carcinogenic risk was 3.4 × 10–3, with Cr the major risk contributor and cereals and meat the dominant food sources. The findings demonstrated that (1) the metal(loid) dietary exposure risk of children from areas with intensive smelting activities should be taken seriously, and (2) it is necessary to identify the specific food category and metal(loid) based on a comprehensive analysis of the metal(loid) concentration and bioaccessibility, and dietary habits of the population to effectively reduce risk.

AbstractBiochar can improve soil health and fix CO2 by altering soil microenvironment, thus impacting the global carbon cycle and the change of soil ecological environment. Recent studies show that cotton byproduct-derived biochar is a potential effective amendment for soil improvement so that it could play an important role in agricultural and environmental conservation. In this work, research topics on cotton byproduct-derived biochar in soil in last decade and so are systematically reviewed for better understanding of the progresses of cotton byproduct-derived biochar in (i) the morphologic and physicochemical characterization, (ii) latest research hotspots and trends, (iii) the roles in soil reclamation, and (iv) relevant carbon sequestration mechanisms. Finally, the future research directions regarding cotton byproduct-derived biochar mingled to soil environment are discussed. Insight derived from this work would provide scientific basis for promoting more applications of cotton byproduct-derived biochar in soil ecological restoration and carbon fixation.
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