Molybdenum ore tailings, iron ore tailings and waste glass powders are important industrial solid wastes, mainly composed of silicate minerals and quartz, which are expected to become alternative resources for inorganic nonmetal industrial materials. In this paper, the ultra-lightweight ceramsite was prepared by the synergistic sintering of molybdenum ore tailings, iron ore tailings and waste glass powders according to their characteristics of silicate minerals. The physical and mechanical properties were investigated when the sintering temperature was between 1100 and 1140 degrees C. The evolution of mineral phases and formation mechanism of pore structure during sintering were studied by XRD, FT-IR, SEM, TG-DSC and HSM. The results showed that in the sintering process, the waste glass powders and the pargasite in iron ore tailings first melted to produce the initial liquid phases. Then the anorthoclase and the quartz in molybdenum ore tailings melted to produce a large amount of liquid phases. These liquid phases covered the gas generated by the oxidation of SiC, thus forming a rich pore structure. At the same time, the [Si2O64-] and Ca2+, Mg2+ in the liquid phases derived from quartz and pargasite melting recrystallized to form diopside, which was conducive to the improvement of mechanical properties of ceramsite. When the raw material ratio of molybdenum ore tailings, iron ore tailings and waste glass powders was 6:2:2 and the sintering temperature was 1120 degrees C, the pore structure of the ceramsite as prepared was uniform and rich and mostly closed. The density was low and the mechanical propertities were excellent. It has a good application prospect in the field of building thermal insulation and sound insulation.

Tobacco black shank (TBS) is a soil-borne fungal disease caused by Phytophthora nicotiana (P. nicotianae), significantly impeding the production of high-quality tobacco. Molybdenum (Mo), a crucial trace element for both plants and animals, plays a vital role in promoting plant growth, enhancing photosynthesis, bolstering antioxidant capacity, and maintaining ultrastructural integrity. However, the positive effect of Mo on plant biotic stress is little understood. This study delves into the inhibitory effects of Mo on P. nicotianae and seeks to unravel the underlying mechanisms. The results showed that 16.32 mg/L of Mo significantly inhibited mycelial growth, altered mycelial morphological structure, damaged mycelial cell membrane, and ultimately led to the leakage of cell inclusions. In addition, 0.6 mg/kg Mo applied in soil significantly reduced the severity of TBS. Mo increased photosynthetic parameters and photosynthetic pigment contents of tobacco leaves, upregulated expression of NtPAL and NtPPO resistance genes, as well as improved activities of SOD, POD, CAT, PPO, and PAL in tobacco plants. Furthermore, Mo could regulate nitrogen metabolism and amino acids metabolism to protect tobacco plants against P. nicotianae infection. These findings not only present an ecologically sound approach to control TBS but also contribute valuable insights to the broader exploration of the role of microelements in plant disease management.

Excessive tailings accumulation leads to secondary disasters and environmental pollution. Although the tailings used in this experiment have been filtered by beneficiation, the tailings soil itself has low strength and is not suitable for direct use as engineering materials. In order to make better secondary use of molybdenum tailings and improve the mechanical properties of tailings soil, the basalt fibre reinforcement method was used to improve the strength of tailings soil. We assessed the reinforcement embedding effect of fibre reinforcement in molybdenum tailings from macro and micro perspectives. Triaxial shear tests and numerical simulations of rigid fibre-modified tailings were performed and compared with indoor tests. We obtained the stress-strain curve, inter-particle displacement field, and soil particle friction cloud map. Tailings had fine- and medium-grained embedded particles with strong roughness and minimal agglomeration. Fibres exhibited good support and shear resistance. Microscopic analysis confirmed excellent tailings particle embedding. Under different confining pressures, the optimal combination of triaxial shear strength was as follows: water-cement ratio was 0.17, fibre content was 0.8% and fibre length was 9 mm. The results of laboratory triaxial test show that the peak strength of basalt modified tailings is increased by 21.70% compared with that of unmodified molybdenum tailings. By exploring the mechanical properties of fibre modified molybdenum tailings, it is found that basalt fibre can improve the strength of molybdenum tailings sand, and provide a reference for the application of fibre modified sand in civil engineering.

Environmental context Mitigating the environmental fallout of industrial accidents is crucial. In a recent study, researchers conducted tests on model substrates to explore the effectiveness of bioremediation in treating complex refinery contaminants resulting from both accidental and deliberate facility damage. The research reveals that bioremediation can be a promising, eco-friendly solution for cleaning up such pollutants, aligning with broader efforts to combat environmental harm resulting from industrial incidents.Rationale Bioremediation harnesses microorganisms' diverse metabolic abilities to detoxify and eliminate pollutants, particularly hydrocarbon-based ones such as oil. This natural biodegradation process performed by microorganisms is a cost-effective method for environmental cleanup compared to other remediation technologies.Methodology In this study, we examined the fate of heavy metals, cobalt and molybdenum, by the analysis of the basic chemical parameters of other sample components, such as n-hexane extractable substances and total petroleum hydrocarbons. The metal content was determined using inductively coupled plasma-optical emission spectrometry (ICP-OES). Exchangeable (loosely bound to the surface of particles and due to its high mobility and availability is crucial for understanding the potential immediate impact of metal contamination) and more stable fractions of the metal and the metal forms were determined using a sequential extraction method. The phase composition of the samples was determined by X-ray diffraction.Results In our microbiological analysis, we isolated various cultures from a consortium of microorganisms. Basic chemical analysis indicators, such as n-hexane extractable substances, total petroleum hydrocarbons and humic acids, reflected robust microbiological activity. During the study, metals in exchangeable form decreased and those in more stable forms increased.Discussion The sequential extraction of cobalt and molybdenum revealed shifts in various metal fractions within the bioaugmented substrate post-bioremediation, differing from the initial substrate. These alterations in metal fractions are likely attributable to microbial actions, leading to the formation of more stable metal fractions throughout the bioremediation process.