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On a global scale, the demand for mineral products has increased substantially with economic development. Consequently, the mining of mineral resources results in the production and accumulation of a large number of tailings, causing many problems with respect to mining, the environment, and the economy. In the mining process, tailings must be reasonably treated to prevent them from entering the water cycle through rivers. The storage of tailings under water can effectively hinder the chemical reactions that they undergo. Therefore, it is a critical practice to store these substances in ponds or impoundments behind dams. However, tailings dams frequently fail, resulting in the discharge of significant quantities of tailings into the natural environment, thereby causing grievous casualties and serious economic losses. This paper discusses reasons including seepage, foundation failure, overtopping, and earthquake for tailings dam failures and explores failure mechanisms by referring to the available literature. This research has determined that the failure of tailings dams is closely related to the state of the country’s economy. Most of the tailings dam breakages in developed countries occurred decades ago. In recent years, the proportion of tailings dam failures in developing countries has been relatively high. Considering the serious damages caused by tailings dam breakage, it is important to understand the main reasons and mechanisms for their failure. The purpose of this review is to provide a reference for the design and construction to the building of the tailing dams and to reduce the occurrences of their failure.

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A facile and effective way for the preparation of nano-sized Fe3O4@graphene yolk-shell nanoparticles via a hydrothermal method is developed. Moreover, the targeting properties of the materials for anticancer drug (doxorubicin hydrochloride) delivery are investigated. Excitingly, these hybrid materials possess favorable dispersibility, good superparamagnetism (the magnetic saturation value is 45.740 emu g(-1)), high saturated loading capacity (2.65 mg mg(-1)), and effective loading (88.3%). More importantly, the composites exhibit strong pH-triggered drug release response (at the pH value of 5.6 and 7.4, the release rate was 24.86% and 10.28%, respectively) and good biocompatibility over a broad concentration range of 0.25-100 μg mL(-1) (the cell viability was 98.52% even at a high concentration of 100 μg mL(-1)) which sheds light on their potentially bright future for bio-related applications.

In this paper, the thermal properties of graphene oxide (GO) with vacancy defects were studied using a non-equilibrium molecular dynamics method. The results showed that the thermal conductivity of GO increases with the model length. A linear relationship of the inverse length and inverse thermal conductivity was observed. The thermal conductivity of GO decreased monotonically with an increase in the degree of oxidation. When the degree of oxidation was 10%, the thermal conductivity of GO decreased by ~90% and this was almost independent of chiral direction. The effect of vacancy defect on the thermal conductivity of GO was also considered. The size effect of thermal conductivity gradually decreases with increasing defect concentration. When the vacancy defect ratio was beyond 2%, the thermal conductivity did not show significant change with the degree of oxidation. The effect of vacancy defect on thermal conductivity is greater than that of oxide group concentration. Our results can provide effective guidance for the designed GO microstructures in thermal management and thermoelectric applications.

Biocoordination polymer (BCP) nanowires are successfully constructed through self-assembly of chiral cysteine amino acids and Cd cations in solution. The varied chirality of cysteine is explored to demonstrate the difference of BCP nanowires in both morphology and structure. More interestingly and surprisingly, the electrical property measurement reveals that, although all Cd(II)/cysteine BCP nanowires behave as semiconductors, the conductivity of the Cd(II)/dl-cysteine nanowires is 4 times higher than that of the Cd(II)/l-cysteine or Cd(II)/d-cysteine ones. The origin of such chirality-discriminated characteristics registered in BCP nanowires is further elucidated by theoretical calculation. These findings demonstrate that the morphology, structure, and property of BCP nanostructures could be tuned by the chirality of the bridging ligands, which will shed light on the comprehension of chirality transcription as well as construction of chirality-regulated functional materials.

Conductive hydrogels with fluidic nanochannels represent one of the most promising capacitive electrodes due to their highly porous structure for the rapid kinetics of electrolyte ion transport. Recent advances in conducting polymers, graphene, and transition metal carbide (MXene)-based hydrogel materials have indicated appealing potential in electrochemical energy storage. The construction of conductive transition-metal dichalcogenide (TMD) hydrogels is still a challenge. In this work, by understanding the colloidal properties of solution-processable 1T molybdenum disulfide (MoS2) nanosheets, we develop a surface-charge-control strategy by changing the electrostatic repulsions for fabricating a freestanding conductive MoS2 hydrogel with three-dimensional (3D) porous structure. Given the interpenetrating ionic transport network, the conductive MoS2 hydrogel, as the electrode of symmetric supercapacitors, exhibits an extremely small time constant of 0.09 s and high power density of 7.0 × 104 W kg–1 under a large current density of 50 A g–1, which is superior to the conventional 2D-MoS2 electrode.

A facile and effective sensor array consisting of three cataluminescence (CTL) sensors based on nanomaterial Y(2)O(3), γ-Al(2)O(3) and ZrO(2) as probes was firstly proposed for the molecular recognition and quantitative analysis of xylene isomers. Under the optimized conditions, the linear range of CTL intensity versus concentration of xylene isomers was 86.70-8670.00 mg m(-3). The use of a sensor array instead of a single sensor has provided a novel strategy for the process of identifying similar chemical compounds, which should have a bright future in environmental and industrial monitoring.