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Lead-zinc (Pb–Zn) tailings ponds carry the risk of multiple heavy metals (HMs) contamination and pile destabilization. This poses requirements for in-situ applicable, low-distribution, and effective stabilization/solidification (S/S) methods. For this, the novel enzymatically induced phosphate precipitation (EIPP) method was implemented in this study. Its mechanism and performance on stabilization of composite Pb, Zn, and cadmium (Cd) in tailings were explored and evaluated under typical erosion conditions for the first time. Results show that the EIPP stabilized HMs by chemically transforming the unstable carbonate-bound HMs to stable phosphate precipitates and by physically encapsulating tailings particles with newberyite precipitates. The stabilization effect on the three HMs was ranked as Pb > Zn > Cd. Comparing magnesium resources for the EIPP reactants, the EIPP utilizing Mg(CH 3 COO) 2 was more effective at decontamination than MgCl 2 because its special pre-activation and re-precipitation function enhanced the chemical transformation function of EIPP. The EIPP stabilization was confirmed to reduce simulated acid rain-leachable and bio-extractive HMs by about 90% and 60%, respectively. Under the prolonged acid attack, treated HMs were ultimately leached through the dissolution mechanism. Zn exhibited significant instability in highly acidic conditions (pH = 2.5–3.5), where its cumulative leaching toxicity after long-term dissolution warrants attention. Overall, EIPP presents a novel and effective strategy for on-site mitigation of composite HMs pollution. [Display omitted] • The EIPP biomineralization method effectively stabilizes Pb, Zn, and Cd in tailings. • The pre-activation and re-precipitation process is the core of EIPP stabilization. • EIPP treatment reduces the acid-leachability and bioextractability of heavy metals. [ABSTRACT FROM AUTHOR]

Hepatitis C virus (HCV) infection continues to be a major public health concern in China. There is little information available in the literature about age- and sex-specific HCV incidence trends. The goal of this study was to examine recent trends in HCV incidence rates in Hunan, China, according to age and gender. A descriptive study was implemented with a joinpoint analysis. Based on the annual reported incidence data of hepatitis C in Hunan, China, from 2004 to 2017, we performed a joinpoint regression analysis to examine trends in the annual percentage change (APC) and the average annual percentage change (AAPC) in the incidence of HCV infection throughout the study period; we stratified the analysis by gender and age. The software calculates the APC, AAPC and the 95% confidence intervals for each trend segment and tests whether the slope for each segment has a significant difference from the prior segment using a Z test. From 2004 to 2017, the overall incidence rate of HCV infection rose from 0.93 per 100,000 to 20.88 per 100,000 (AAPC, 25.2%). In particular, women aged ≥65 years had the fastest increasing rate (AAPC, 29.9%). The incidence of different demographic groups showed no significant difference in increasing trends before 2013. However, new patterns emerged after 2013: the incidence of people aged 0–14 years was no longer significantly elevated; a significant yearly decline occurred in the incidence of HCV in people aged 15–29 years; the incidence of HCV in people aged ≥30 years continued to increase, with significantly slower increasing rates than before; and women aged ≥65 years showed a significantly higher yearly increase in incidence than that in men in the same age group (APC, 11.1% in women versus 5.3% in men). The overall increasing rate of HCV infection significantly slowed after 2007 and 2013. The differences in incidence trends among demographic groups have obviously increased in the last 5 years, and the reasons underlying these different trends urgently require further study. People in older age groups, especially women aged ≥65 years, still experienced increases in incidence rates in the last 5 years. This finding indicates that programmes for the prevention and control of HCV infection in older people require continued strengthening. • This study describes the age- and sex-specific incidence trends of hepatitis C virus (HCV) infection in Hunan, China. • Joinpoint model illustrated the annual percentage change of HCV infection incidence trend. • Time trends of HCV infection incidence rates show significant changes over time. • The differences in incidence trends among demographic groups have obviously increased in the last 5 years. • People in high-age groups have still experienced increases in incidence rates in the last 5 years. [ABSTRACT FROM AUTHOR]

• The new method detected petroleum compositions and contents on the site. • The new method measured heterogeneous soil and groundwater TPH contents in-situ. • The in-situ remediation dynamics was monitored at the soil-groundwater interface. • Micro-area in-situ dynamics studies revealed different ISCO remediation mechanisms. The mechanistic study of soil and groundwater remediation in petroleum contaminated lands significantly demands rapid qualitative and quantitative identification of petroleum substances. However, most traditional detection methods cannot provide the on-site or in-situ information of petroleum compositions and contents simultaneously even with multi-spot sampling and complex sample preparation. In this work, we developed a strategy for the on-site detection of petroleum compositions and in-situ monitoring of petroleum contents in soil and groundwater using dual-excitation Raman spectroscopy and microscopy. The detection time was 0.5 h for the Extraction-Raman spectroscopy method and one minute for the Fiber-Raman spectroscopy method. The limit of detection was 94 ppm for the soil samples and 0.46 ppm for the groundwater samples. Meanwhile, the petroleum changes at the soil-groundwater interface were successfully observed by Raman microscopy during the in-situ chemical oxidation remediation processes. The results revealed that hydrogen peroxide oxidation released petroleum from the interior to the surface of soil particles and then to groundwater during the remediation process, while persulfate oxidation only degraded petroleum on the soil surface and in groundwater. This Raman spectroscopic and microscopic method can shed light on the petroleum degradation mechanism in contaminated lands, and facilitate the selection of suitable soil and groundwater remediation plans. [Display omitted] [ABSTRACT FROM AUTHOR]

Carbon Fiber Reinforced Plastics (CFRPs) are widely used in aerospace, automotive and other transportation industries because of their excellent material and mechanical properties. Nevertheless, up to now, drilling is still regarded as the most important process in the machining of CFRPs, and the delamination is one of the most challenging damage in drilling process. In this concern, we propose and implement a bi-directional drilling method for CFRPs hole-making. In this paper, the exit delamination formation mechanism was firstly analyzed to clarify the effect of bi-directional drilling on delamination suppression. The critical thrust force was calculated by considering both conventional and bi-directional drilling conditions. Based on the model, it can find that bi-directional drilling process itself can provide support without employing any extra facility. Finally, experimental validation indicates that the calculated critical thrust force showed a reasonable agreement with the experimental results based on conventional and bi-directional drilling. The hole exit delamination damage under the bi-directional drilling reaches the desired suppression effect with a reduction of 11.3%–27.9% compared to conventional drilling based on experiment results. Through an in-depth understanding of critical thrust force, the findings of this paper not only provide a new processing technology for drilling CFRPs, but also open a new avenue to improve the quality of drilling CFRPs by reducing delamination. [ABSTRACT FROM AUTHOR]

Identifying the active sites and their dynamic changes is of critical significance for designing efficient oxygen evolution reaction (OER) catalysts, but remains challenging owing to the complexity in structure and reaction process. Herein, using various operando characterizations, we identify the origin of a 12-time enhancement of OER activity over pure cobalt oxyhydroxide achieved by confining high-valance chromium into its lattice. Operando X-ray absorption spectroscopy reveals in-situ generation of high-valence Cr state with shortened Cr O bond relative to original state, indicating potential-dependent formation of OER intermediates on Cr sites. Operando electrochemical impedance and infrared spectroscopy provide direct spectroscopic evidence of OOH* on Cr site. Combined with theoretical calculations, the confined Cr is identified as the active site with improved bonding strength with O*, exhibiting a lower overpotential than that on Co site. This study elucidates the dynamic behaviour of active sites and provides guiding for improving OER catalysts via introducing high-valance metals. Layered cobalt oxyhydroxide showed a 12-fold OER activity enhancement after confining chromium. Various operando characterizations revealed the potential-relevant electronic and structural dynamics of Co and Cr under realistic working conditions, identifying that high-valence Cr is the active site with moderate bond strength with reaction intermediates. [Display omitted] • The origin of a 12-time OER activity enhancement is identified by various operando characterizations. • Operando electrochemical impedance and X-ray absorption spectroscopy reveal the dynamic evolutions of the Co and Cr sites. • Operando infrared spectroscopy provide direct spectroscopic evidence of OOH* intermediates on Cr site. • High-valence Cr is identified as the active site with moderate bond strength with reaction intermediates. [ABSTRACT FROM AUTHOR]

Background: Immune activation, chronic inflammation, and renal interstitial fibrosis (RIF) are associated with chronic kidney disease (CKD). The herbal formula, Shenkang injection (SKI), has been reported to attenuate RIF. However, the mechanisms by which SKI alleviates renal fibrosis, especially the role of natural killer (NK) cells, are unknown and require exploration.Purpose: This study aimed to determine the mechanisms by which SKI alleviates RIF.Methods: Differential gene expression between CKD mice and control groups was explored using bioinformatics analysis. To reveal how SKI reduces RIF in CKD, a CKD mouse model was established using folic acid for in vivo studies, and human kidney-2 cells were used for in vitro experiments. The effects of various SKI doses were then determined. Immunohistochemical staining, Enzyme-linked immunosorbent assay, western blotting, and quantitative real-time PCR were used for pathological and molecular expression detection.Results: We first investigated the potential immune dysfunction in CKD using bioinformatics analysis. Some differentially expressed genes were enriched in immune-related functions. The expressions of perforin and interferon (IFN)-γ, which are mainly released by NK cells, were significantly higher in patients with CKD (p< 0.05). In vivo experiments showed that SKI alleviated renal fibrosis in a folic acid-induced renal fibrosis model. Serum creatinine and blood urea nitrogen levels were reduced in the high-dose SKI-treated group. Additionally, the mRNA and protein expression levels of type IV collagen and alpha-spinal muscular atrophy were reduced. Biochemical detection showed that SKI could also downregulate the activity of NK cells (by decreasing the expressions of perforin and IFN-γ). Increased levels of stimulator of interferon genes (STING)/TANK-binding kinase 1 (TBK1)/IFN regulatory factor 3 (IRF3), phosphorylation of TBK1, and IRF3 in FA-induced RIF mice were alleviated by SKI treatment, which was consistent with the results of in vitro experiments.Conclusion: These results demonstrated that SKI could decrease the activation of NK cells via the STING/TBK1/IRF3 signaling pathway, thereby alleviating RIF and protecting renal function in CKD. This may provide valuable evidence supporting the clinical use of SKI in the treatment of patients with CKD. [ABSTRACT FROM AUTHOR]

In this work, the dual-phase structure Mn–Co–Fe–Zn–Ni–O high-entropy negative temperature coefficient (NTC) ceramics were synthesized by a solid-phase reaction method. The ceramics are mainly composed of the cubic spinel phase and the rock salt phase. Electron microscopic images revealed the typical morphology and the homogeneous distribution of all elements. The results confirmed that the microstructure and electrical properties of the high-entropy ceramics are closely related to the sintering temperature. As the sintering temperature increased, the content of the rock salt phase gradually improved, meanwhile, the higher resistivity of samples was achieved. Notably, it was found that an appropriate proportion of the rock salt phase could significantly enhance the aging stability of ceramics. The aging drift of the samples sintered at 1175 °C was only 0.632 %. In addition, the ratio of the two phases was adjusted by adding NiO. The ρ 25 and B 25/50 of the materials can be tuned in the range of 22.25 kΩ cm∼24.19 kΩ cm and 4047 K–4145 K, respectively. Regulating the phase ratio of dual-phase materials is a novel strategy for designing NTC ceramic materials with excellent characteristics. This work provides an idea for future research on high-entropy NTC thermistor ceramics. [ABSTRACT FROM AUTHOR]

Here, a novel type of high-entropy (Co 0.2 Mn 0.2 Fe 0.2 Zn 0.2 Al 0.2) 3 O 4 solid-solution ceramics with spinel phase structure was designed and successfully fabricated based on an entropy engineering approach. Additionally, the impact of sintering temperature, a critical factor in entropy stabilization, on structural and electrical behavior was systematically examined at a range of 1110∼1150 °C. The results indicate that each synthesized sample exhibits a single spinel structure in the F d ‾ 3 m (227) space group, and all five metal elements were uniformly distributed, demonstrating entropy stabilization. Meanwhile, the fabricated high-entropy ceramics manifest exceptional negative temperature coefficient (NTC) characteristics in the temperature range of 25 °C–350 °C. The aging stability is excellent as well. After aging at 150 °C for 1000 h, the ΔR/R 0 of thick-film samples sintered at 1150 °C is less than 1 %. The successful synthesis of this novel class of spinel-type high-entropy ceramics introduces an emerging design approach for the development of NTC thermistors, particularly for applications in medium-temperature environments. [ABSTRACT FROM AUTHOR]

• Lithium-rich manganese-based cathode materials doped with S/Fe ions were obtained directly using electrolytic manganese anode mud wastes. • First principles are adopted to prove that the S/Fe ions doped Li 1.2 Ni 0.2 Mn 0.6 O 2 material prepared from anode mud has higher conductivity. • Surfactants are introduced in the preparation of precursor materials to obtain materials with fine particles and excellent performance. • This study provides a new idea for the value-added utilization of anode mud and the preparation of low-cost, high-performance LIBs. The booming electrolytic manganese industry has brought a huge amount of electrolytic manganese anode mud (EMAM). The management and value-added recovery of EMAM were very important for environmental improvement and economic benefits. In this study, EMAM is used as a cost-effective raw material. Firstly, the manganese-containing solution was obtained by reducing acid leaching with EMAM. Then, Li 1.2 Ni 0.2 Mn 0.6 O 2 (Z-LNMO) cathode materials were prepared from a manganese-containing solution by co-precipitation process. Finally, to enhance the performance of the Z-LNMO materials, surfactants (C 12 H 25 SO 4 Na, C 10 H 14 N 2 Na 2 O 8 , C 18 H 29 NaO 3 S, C 19 H 42 BrN) were introduced in the preparation of precursor materials to obtain the material with higher crystallinity. ICP results showed that S/Fe ions of EMAM were retained in Z-LNMO materials. Moreover, the Z-LNMO sample shows a stoichiometric similar element content to Li 1.2 Ni 0.18 Fe 0.02 Mn 0.6 O 1.96 S 0.04. EDS results show that S/Fe ions were uniformly distributed in Z-LNMO materials. The shift of XRD peak further indicates that the use of EMAM waste is expected to directly obtain S/Fe ions doped lithium-rich manganese-based cathode materials. The first-principle calculation shows that the S/Fe ions as the doping source make the transfer of excited electrons from the valence band to the conduction band easier, thereby enhancing the conductivity of the materials. The CV curve and differential capacity (dQ/dV) curve show that the Z-LNMO material prepared by EMAM inhibits the excessive oxidation of Li 2 MnO 3 to a certain extent, thus providing excellent reversible capacity and stabilizing the material structure. Electrochemical evaluation reveals that the Z-LNMO materials prepared with the EMAM exhibit superior cycling stability (112% after 100 cycles at 0.1C). Moreover, the introduction of C 10 H 14 N 2 Na 2 O 8 (EDTA-2Na) and C 12 H 25 SO 4 Na (SDS) in the preparation of precursor materials can improve the first discharge-specific capacity and stability of materials by modifying the morphology of precursor materials (refine particles). Among them, the materials modified by EDTA-2Na show the best performance, and the particle size is about 200 nm. Compared with the original materials, the improved first discharge-specific capacity (218.6 mAh g−1 at 0.1C) and capacity retention (245.8 mAh g−1 after 100 cycles) of the materials modified with EDTA-2Na were improved. The EIS results also confirm that the introduction of EDTA-2Na effectively decreases the charge transfer resistance and facilitates the Li diffusion of the as-prepared cathode materials. This work confirmed the possibility of extracting manganese from EMAM to prepare lithium-rich manganese-based cathode materials, and provided a new promising way for the efficient value-added utilization of EMAM. [Display omitted] The industrial waste of electrolytic manganese anode slime is recycled into MnSO 4 by a simple leaching process, and then the carbonate precursor is prepared by an industrial coprecipitation process (and the surfactants are introduced to modify the material morphology), and finally, the high-performance lithium-rich manganese-based cathode material is obtained by calcination. [ABSTRACT FROM AUTHOR]

[Display omitted] • A method to extract weld feature points based on CenterNet without prior frames is proposed. • The key point detection used in this method does not require morphological processing. • This method has high accuracy and robustness on three typical weld image datasets. To realize strong robust, widely adaptable and highly precise weld seam feature detection, an extraction method based on the improved target detection model CenterNet is proposed. In this target detection method, the weld feature points on the laser strip are taken as the center points of the bounding box. This eliminates the need for an initial positioning frame. When dealing with multiple welds, an independent classifier is used to predict the weld type, which can avoid false detection. In post-processing, this result is used to determine the number of feature points to filter out suspicious targets. The method was tested with the welding image dataset of three typical welds. The classification efficiency of the three welds can reach 99.359 %, with an average extraction error of 1.754 pixel and an average processing time of 32.186 ms. The proposed method exhibits high performance in dealing with common welding images with time-varying noise. [ABSTRACT FROM AUTHOR]

• Pharmaceutical sludge biochar (PSBC) was used to activate peroxymonosulfate (PMS). • PSBC/PMS removed 4-CP effectively with high rate constants of 0.42–1.70 min−1. • Rising pyrolysis temperature shifted reactive species from FeIVO2+ to SO 4 ·−/·OH. • FeN x and Fe x N in PSBC were active sites of PMS to produce FeIVO2+ and SO 4 ·−/·OH. Pyrolysis of pharmaceutical sludge (PS) is a promising way of safe disposal and to recover energy and resources from waste. The resulting PS biochar (PSBC) is often used as adsorbent, but has seldom been explored as catalyst. Herein we demonstrate that PSBC (0.4 g/L) could efficiently activate peroxymonosulfate (PMS) to 100% degrade 4-chlorophenol (4-CP) with rate constants of 0.42–1.70 min−1, outperforming other reported catalysts. Interestingly, the PMS activation pathway highly depended on PSBC pyrolysis temperature, which produced dominantly high-valent iron species (e.g., FeIVO2+) at low temperature but more sulfate radical (SO 4 ·−) and hydroxyl radical (·OH) at higher temperature, e.g., 0.17, 0.23, 0.12 mmol/L of FeIVO2+ and 0.009, 0.038, 0.102 mmol/L of SO 4 ·−/·OH were produced within 10 min by PSBC-600/PMS, PSBC-800/PMS, and PSBC-1000/PMS, respectively. Characterization, density functional theory (DFT) simulation and Pearson correlation analysis revealed that along with the increase of pyrolysis temperatures, the active sites of PSBC gradually shifted from atomically dispersed N-coordinated Fe moieties (FeN x) to iron nitrides (Fe x N), which activated PMS to produce FeIVO2+ and SO 4 ·−/·OH, respectively. This study clarifies the structure-activity relationships of PSBC for PMS activation, and opens a new avenue for the treatment and utilization of PS as high value-added resources. [Display omitted] [ABSTRACT FROM AUTHOR]

Accurate tool wear prediction is the key to evaluating tool usability and ensuring drilling quality. Recently, fusion prediction methods have attracted great attentions. However, no similar work has been reported yet in ultrasonic vibration-assisted drilling (UVAD) of carbon fiber reinforced polymer (CFRP). To fill this gap, a hybrid data-driven physics model-based framework for predicting tool wear is proposed. The physics model builds a mathematical description of the tool wear degradation process. The data-driven model predicts tool wear based on multilayer perceptron (MLP). The fusion method fuses the results of both models based on particle filter to obtain the final tool wear. Results indicate that the hybrid model performs better than any of individual models, with the lowest prediction errors. [ABSTRACT FROM AUTHOR]

• ZVI/H2O2 delivers a controllable reduction-oxidation coupling process for CNBs remediation. • ZVI pre-reduction significantly accelerates CNBs mineralization rate by ·OH. • The performance of ZVI/H2O2 based reduction-oxidation process is controlled by the addition time of H2O2. • The efficiency of this controllable reduction-oxidation process has been validated in remediating real site contaminated by CNBs. Chloronitrobenzenes (CNBs) are typical refractory aromatic pollutants. The reduction products of CNBs often possess higher toxicity, and the electron-withdrawing substituent groups are detrimental to the ring-opening during the oxidation treatment, leading to ineffective removal of CNBs by either reduction or oxidation technology. Herein we demonstrate a controllable reduction-oxidation coupling (ROC) process composed of zero-valent iron (ZVI) and H 2 O 2 for the effective removal of CNBs from both water and soil. In water, ZVI first reduced p-CNB into 4-chloronitrosobenzene and 4-chloroaniline intermediates, which were then suffered from the subsequent oxidative ring-opening by ·OH generated from the reaction between Fe(II) and H 2 O 2. By controlling the addition time of H 2 O 2 , the final mineralization rate of p-CNB reached 6.6 × 10−1 h−1, about 74 times that of oxidation alone (9.0 × 10−3 h−1). More importantly, this controllable ROC process was also applicable for the site remediation of CNBs contaminated soil by either ex-situ treatment or in-situ injection, and, respectively decreased the concentrations of p-CNB, m-CNB, and o-CNB from 1105, 980, and 94 mg/kg to 3, 1, and < 1mg/kg, meeting the remediation goals (p-CNB: < 32.35 mg/kg, o-CNB and m-CNB: < 1.98 mg/kg). These laboratory and field trial results reveal that this controllable ROC strategy is very promising for the treatment of electron-withdrawing groups substituted aromatic contaminates. [Display omitted] [ABSTRACT FROM AUTHOR]