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Co-presence of organic pollutants and heavy metals in soil is causing increasing concerns, but the lack of knowledge of relation between soil ecology and pollutant fate is limiting the developing of specific control strategy. This study investigated soil change under pyrene stress and its interaction with cadmium (Cd). Soil physicochemical properties were not seriously influenced. However, pollutants' presence easily varied soil microbial activity, quantity, and diversity. Under high-level pyrene, Cd presence contributed to soil indigenous microorganisms' adaption and soil microbial community structure stability. Soils with both pyrene and Cd presented 7.11–12.0% higher pyrene degradation compared with single pyrene treatment. High-throughput sequencing analysis indicated the proportion of Mycobacterium sp., a commonly known PAHs degrader, increased to 25.2–48.5% in treatments from 0.52% in control. This phenomenon was consistent with the increase of PAHs probable degraders (the ratio increased to 2.86–6.57% from 0.24% in control). Higher Cd bioavailability was also observed in soils with both pollutants than that with Cd alone. And Cd existence caused the elevation of Cd resistant bacterium Limnobacter sp. (increased to 12.2% in CdCK from 2.06% in control). Functional gene prediction also indicated that abundance of genes related to nutrient metabolism decreased dramatically with pollutants, while the abundances of energy metabolism, lipid metabolism, secondary metabolites biosynthesis-related genes increased (especially for aromatic compound degradation related genes). These results indicated the mutual effect and internal-interaction existed between pollutants and soils resulted in pollutants' fate and soil microbial changes, providing further information regarding pollutants dissipation and transformation under soil microbial response. Image 1 • Cd existence contributed to the dissipation of pyrene in soil. • Cd presence helped microorganisms adaption under high level pyrene stress. • Resistance microbe enrichment contributed to nature attenuation of pyrene pollution. • Cd contributed to soil microbial diversity maintenance under high pyrene stress. The effect of internal interaction between soil ecosystem and pollutants on pollutants fate and soil microbial community. [ABSTRACT FROM AUTHOR]

A novel nano-composite material (CMC-FeS@HA) combining the advantages of humic acid (HA) and FeS was synthesized to remediate hexavalent chromium (Cr(VI)) contaminated soil along with chromium (Cr) resistant microflora. The characteristic analysis confirmed the successful synthesis of the nano-composite, which provided further mechanism evidence of its detoxification effect on polluted soil. Energy Dispersive System analysis proved the adsorption of the microbe consortium (MC) for Cr. After remediation, Cr(VI) in all treatments was dramatically reduced and the leachable Cr in soil treated by CMC-FeS@HA and MC decreased 89.14% compared with control. The result of BCR sequential extraction showed that Cr was stabilized, whose form changed to oxidizable and residual from HOAC-extractable. Besides, CMC-FeS@HA, as a sustained-release acid with high biocompatibility, could continuously decrease the pH of strongly alkaline soil and created a suitable micro-ecological environment for soil microorganisms. Moreover, CMC-FeS@HA dramatically improved soil physicochemical property, soil microbial activity (dehydrogenase, hydrolase, urease, and invertase activities), and soil microecological diversity. In total, this study provided a useful technology for soil remediation, which innovatively combined chemical remediation and microbial-remediation with a positive effect on soil quality, providing a good approach for the multiple technology combination in the environmental cause. Image 1 • Humic acid (HA) as a supporting material for FeS was first study. • The strongly alkaline soil was gradually improved by CMC-FeS@HA. • Cr(VI) biotoxicity was significantly reduced by CMC-FeS@HA and Cr-resistant microflora. • The effect of nano-composite materials on soil microecology were first studied in Cr(VI) contaminated remediation. [ABSTRACT FROM AUTHOR]

A soil heavy metal decontamination system was developed based on the immobilization of bioavailable metal fraction by iron-biochar nano-complex (BC@Fe 3 O 4) and the uptake by Chromium (Cr) hyperaccumulator Leersia hexandra (L. hexandra) under the assistance of metal resistant microbe consortium (MC). In this system, L. hexandra was able to accumulate 485.1–785.0 mg kg−1 in root and 147.5–297.2 mg kg−1 of Cr in its aerial part. With MC assistance, more Cr could be translocated to the aerial part of L. hexandra , which dramatically improved its remediation potential. Meanwhile, BC@Fe 3 O 4 application decreased bioavailable Cr in soil and reduced soil toxicity, which contributed to soil microbial community adaption and L. hexandra performance under high level of Cr concentration (elevated microbial activity, decreased plant stress response, enhanced L. hexandra growth and accumulation) without negative influence on accumulation efficiency. Moreover, details of the possible mechanistic insight into metal removal were discussed, which indicated a negative correlation of the extractable Cr with soil microecology and hyperaccumulator performance. Furthermore, the resistant bacteria successfully altered soil microbial community, enhanced its diversity, which was in favor of the soil quality improvement. Image 1 • A bottom-up uptake and immobilization system to detoxify Cr polluted soil. • Nano iron composite was applied with hyperaccumulator under microbe assistance. • Microbe consortium helped the uptake and translocation of Cr in L. hexandra. • Mobile Cr was negatively correlated with soil microecology and metal accumulation. An uptake and immobilization system with integration of iron coated biochar and hyperaccumulator with resistant microbe to improve phytoremediation performance. [ABSTRACT FROM AUTHOR]

• This paper proposes an improved sparse deconvolution method named MGGSED-SSA for bearing diagnosis. • A new sparse index is designed based on generalized Gini index for improving anti-noise performance. • Filter coefficients are solved by sparrow search algorithm and generalized spherical coordinate transformation. • Simulation and experimental cases validate the effectiveness and superiority of the proposed method. Sparse deconvolution methods can not only adaptively design the filter to counteract the negative effect of the transmission path but also exhibit superior performance compared to traditional deconvolution methods based on kurtosis. Yet, determining the optimal filter length remains challenging, and there is still further study to be done on how to make sparse deconvolution methods work better under heavy noise and harmonic interference. To address these issues, this paper proposes a novel sparse deconvolution technique named the maximum generalized Gini squared envelope optimized with the sparrow search algorithm (MGGSED-SSA). First, a new sparse index is constructed based on the generalized Gini index, which is less sensitive to filter length and more robust to interference. Second, the MGGSED-SSA is derived by considering the new sparse index as a deconvolution objective function. Third, the sparrow search algorithm is applied to optimize filter coefficients in the generalized spherical coordinate transformation. Simulation cases and experimental cases concerning bearing with inner and outer race faults are used to verify the effectiveness of the proposed method. It can be seen that the proposed method is less sensitive to filter length and holds better diagnosis performance even when bearings suffer from heavy noise and harmonic interference, compared with traditional methods. [ABSTRACT FROM AUTHOR]

Although iron nanoparticles (NPs) have been used for environmental remediation of heavy metal, their potential to remediate lead (Pb) contaminated soil and effect on soil micro-ecology is unclear. The purpose of this study was to investigate the potential of nanoscale zerovalent iron (nZVI), nanoscale zerovalent iron supported by biochar (nZVI@BC), ferrous sulfide (FeS-NPs), ferrous sulfide supported by biochar (FeS-NPs@BC), ferriferrous oxide (Fe 3 O 4 -NPs) and ferriferrous oxide supported by biochar (Fe 3 O 4 -NPs@BC) to remediate Pb contaminated soil and the influences for soil micro-ecology. The results showed that biochar (BC) could improve the crystal shape and superficial area of iron-based nanoparticles. Soil pH values was significantly decreased by FeS-NPs and FeS-NPs@BC, but increased by other iron-nanoparticles. The ability to reduce available Pb concentration showed significant difference among these iron-nanoparticles, that is, the immobilized rate were nZVI by 45.80%, nZVI@BC by 54.68%, FeS-NPs by 2.70%, FeS-NPs@BC by 5.13%, Fe 3 O 4 -NPs by 47.47%, Fe 3 O 4 -NPs@BC by 30.51% at day 90. Almost all soil enzyme activities in Fe 3 O 4 -NPs and Fe 3 O 4 -NPs@BC groups were increased, but the majority of the enzyme activities were inhibited in other iron-based nanoparticles groups, while the maximum bacterial number was determined in FeS-NPs group. Furthermore, microbial diversity analysis showed that FeS-NPs has significantly changed microbial community richness and diversity, followed by nZVI and Fe 3 O 4 -NPs. Accordingly, our results suggested that nZVI@BC had the best immobilization effect on Pb in high-concentration Pb-contaminated alkaline soil, but the toxic effect of Fe 3 O 4 -NPs on soil micro-ecology was relatively minimal. Image 1 • Multiple iron-based nanoparticles were prepared to immobilize Pb in soil. • Immobilized rate of nZVI@BC reached 54.68%. • Soil enzyme activities were significantly enhanced by Fe 3 O 4 -NPs. • Effects of different materials on microbial community structure were discussed. [ABSTRACT FROM AUTHOR]