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Due to the high dependence on the pH of influent water and the level of ferrous species, the applicability of the electro-Fenton (EF) system is poor. A highly applicable dual-cathode (DC) EF system with self-adjusting pH and ferrous species is proposed: gas diffusion electrode (GDE) for generation H 2 O 2 and Fe/S doped multi-walled carbon nanotubes (Fe/S-MWCNT) modification active cathode (AC) for adjusting pH and iron species. The strong synergistic enhancement effect between two cathodes (synergy factor up to 90.3%) improves the catalytic activity of this composite system about 12.4 times higher than that of cathode alone. Impressively, AC has the ability of self-regulate to shift towards the optimal Fenton pH (around 3.0) without adding reagents. Even pH can be adjusted from 9.0 to 3.4 within 60 min. This characteristic gives the system a wide range of pH applications, while avoiding the disadvantage of the high cost of traditional EF in pre-acidification. Furthermore, DC has a high and stable ferrous species supply, and the iron leaching amount is about twice less than that of heterogeneous EF system. Long-term stability of the DC system and its easy activity regeneration exhibit the potential of environmental remediation in industrial application., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023. Published by Elsevier Inc.)

Nitrogen-doped graphene as a perfectly-efficient and environmentally compatible electrocatalyst won widespread attention in electrochemical advanced oxidation processes (EAOP). However, the relationship between surface structure regulation and activity of catalysts is still lacking in systematic scientific guidance. Herein, nitrogen-doped graphene aerogel (NGA) was conveniently prepared through hydrothermal treatment, and then utilized to fabricate the gas diffusion electrode (GDE) as the cathode for tetracycline (TC) removal. High free radical yield (81.2 μM) and fast reaction rate (0.1469 min -1 ) were found in NGA system. The molecular dynamics simulation (MD) results showed that the interaction energy of NGA was greater than the raw graphene aerogel (GA). The adsorption activation of H 2 O 2 and the degradation of TC occurred in the first adsorption layer of catalysts, and both processes turned more orderly after nitrogen doping. Moreover, the van der Waals interaction was stronger than the electrostatic interaction. Density function theory (DFT) revealed that the adsorption energy of H 2 O 2 at graphitic N, pyridinic N, and pyrrolic N sites was -0.03 eV, -0.39 eV, and -0.30 eV, respectively. Pyridinic N sites were inferred as the main functional regions of in-situ activation •OH, there were more likely to occur ectopic reaction in pyrrolic N, and graphitic N were responsible for improving H 2 O 2 production. By revealing the microstructure and activation characteristics of NGA, an experiment-simulation complementary strategy is provided in the EAOP to discover or to optimize new catalysts., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022. Published by Elsevier Inc.)

B-doped graphene, as an efficient and environmental-friendly metal-free catalyst, has aroused much attention in the electrochemical advanced oxidation process (EAOP), but the bottleneck in this field is to determine the relationship between the surface structure regulation and activity of catalysts. Herein, the B-doped graphene aerogel (BGA) fabricated gas diffusion electrode was prepared and used as a cathode for EAOP to remove tetracycline (TC). Higher free radical yield (169.59 μM), faster reaction speed (0.35 min -1 ) and higher TC removal rate (99.93%) were found in the BGA system. Molecular dynamics simulation unveiled the interaction energy of BGA was greater than the raw graphene aerogel (GA). The adsorption-activation process of H 2 O 2 and the degradation process of TC occurred in the first adsorption layer of catalysts. And both processes turned more orderly after B doping, which accelerated the reaction efficiency. Results of density functional theory displayed the contribution of three B-doped structures to improve the binding strength between H 2 O 2 and BGA was: - BCO 2 (-0.23 eV) > - BC 2 O (-0.16 eV) > - BC 3 (-0.09 eV). -BCO 2 was inferred to be the main functional region of H 2 O 2 in-situ activation to hydroxyl radical (•OH), while -BC 2 O and -BC 3 were responsible for improving H 2 O 2 production., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier B.V. All rights reserved.)

Existing receptor-model-based source apportionment methods failed to derive source contributions to accumulation of soil heavy metals (SHMs). In this research, a dynamics-simulation-based source apportionment approach (DSSA) was developed by integrating mathematical models of source release, diffusion and deposition pathway, and receptor accumulation, to quantify accumulative contributions of SHMs. The case study was carried out in a complex industrialized region in southeast China to investigate pollution situation of SHMs (Zn, Pb, Ni, As, Cd, and Cr). The results showed that SHMs distributions were affected by seasonal variation and near-surface meteorology, which could be sequenced by correlation coefficient as temperature (0.968) > humidity (0.552) > precipitation (0.389) > wind speed (0.386). The source categories and corresponding contribution rates were identified as: i) battery plant to Zn (72.32%) and Pb (71.73%), ii) traffic to Ni (64.55%), iii) traffic and agriculture to Cd (43.26%, 41.63%), iv) agriculture to As (75.30%) and Cr (60.05%), which was similar to the results of positive matrix factorization (PMF). Furthermore, DSSA could illustrate SHMs migration process from source to receptor. The uncertainty analysis further proved the distinct advantages of DSSA. The results of this research could predict pollutant enrichment and could provide new perspective for environment and public health management., Competing Interests: Declaration of Competing Interest We wish to confirm that there are no known conflicts of interest associated with this publication and there has been no significant financial support for this work that could have influenced its outcome. We confirm that the manuscript has been read and approved by all named authors and that there are no other persons who satisfied the criteria for authorship but are not listed. We further confirm that the order of authors listed in the manuscript has been approved by all of us. We confirm that we have given due consideration to the protection of intellectual property associated with this work and that there are no impediments to publication, including the timing of publication, with respect to intellectual property. In so doing we confirm that we have followed the regulations of our institutions concerning intellectual property. We understand that the Corresponding Author is the sole contact for the Editorial process (including Editorial Manager and direct communications with the office). She is responsible for communicating with the other authors about progress, submissions of revisions and final approval of proofs. We confirm that we have provided a current, correct email address which is accessible by the Corresponding Author and which has been configured to accept email from (zhangym@ncepu.edu.cn)., (Copyright © 2022. Published by Elsevier B.V.)

Herein, a novel three-dimensional (3D) heterogeneous Electro-Fenton (EF) system with improved gas diffusion electrode (GDE) as cathode and magnetic nitrogen doped/reduced graphene oxide (Fe 3 O 4 /N-rGO) as catalytic particle electrodes (CPEs) was built for Bisphenol A (BPA) removal. The Fe 3 O 4 /N-rGO served as both particle electrodes and heterogeneous catalyst. The study concluded that BPA could be effectively removed via this hybrid system. The synergistic effect between the 3D electrode and EF system was discussed by comparing the performance of different functional particle electrodes. The 3D electrode system exhibited a larger specific surface area electrode, which improved the mass transfer of pollutants to electrode, and also accelerated the regeneration of Fe Ⅱ due to faster electron transfer, thereby enhancing the efficiency of EF catalysis. The EF process promotes the regeneration rate of particle electrodes and thus accelerates the 3D electrode reaction course. The parameters affecting degradation behavior of BPA were optimized. As a result, optimal removal rate of BPA and TOC was 93% and 60.5%, respectively within 90 min. The CPEs showed high catalytic performance (86.5% for BPA and 50.3% for TOC) and low catalyst loss (less than 9.5%) after 5 cycles, indicating its excellent stability and reusability. The possible mechanism of 3D heterogeneous EF was investigated by comparing the catalytic activity and •OH production capacity of homogeneous EF and Fenton-like. Built on the analysis of intermediates, a possible decomposition pathway of BPA was proposed., (Copyright © 2019. Published by Elsevier B.V.)

In China groundwater contamination has become a serious problem. The assessment and remediation of contaminated sites are greatly important. Moreover, only few studies deal with the influence of metal speciation on human health risk assessment. This paper proposed a comprehensive assessment methodology combined human health risk assessment and groundwater vulnerability assessment for contaminated area, exploring a more reasonable model for the Cd morphology simulation, and utilizing accurate method to calculate the average daily dose by the weight analysis. PHREEQC and Visual MINTEQ were applied and compared to the morphology simulation, the modified of average daily dose and non-modified of average daily dose was investigated, carcinogenic and non-carcinogenic risks were calculated subsequently. The groundwater vulnerability was assessed by the DRASTIC model, the DRASTIC index as the indicator of groundwater vulnerability. The morphology simulation results showed 20 and 13 metal species which were simulated by PHREEQC and Visual MINTEQ, respectively. Cd 2+ and CdCl + were the primary species of Cd in groundwater. The modified average daily dose showed less than the average daily dose in results. The carcinogenic risks showed the species of Cd 2+ and CdCl + were simulated by PHREEQC which were harmful to human health. The DRASTIC index was ranged from 109 to 134 in the studied area, which showed that the area was susceptible to pollution. This method provided a more effective risk assessment model and supplied a fundamental advice for government policy-making and site remediation., (Copyright © 2019. Published by Elsevier B.V.)

Assessing human health risk using spatiotemporal migration and geochemical evolution concurrently in an area where the groundwater is contaminated with heavy metals can provide more instructive information to protect specific potential negative impacts on human health. In this research, we established a model of long-term assessment of human health risk for metal contaminated groundwater by coupling two models: the geochemical (based on the law of chemical mass balance) model and the hydrodynamics module. The hydrodynamics module is used to initially identify the total temporal concentration of various elements, and the chemical mass balance module is used to gain the concentration and ionic activity of various toxic elements according to the range of environmental pH. Effective concentrations calculated using activity weight (based on speciation and ionic activity) were introduced into the formula for risk analysis. The results of the study show that, with the exploitation and recharge of groundwater, the non-carcinogenic and carcinogenic health risks cannot be reduced to acceptable levels until 18 and 22 years, respectively. The calculated risk values of using the coupling model are lower than that of statistics or single hydrokinetics. The sensitivity analysis results show that this model is reliable. The recharge, pH and the permeability coefficient are defined as the most sensitive factors., (Copyright © 2019 Elsevier Inc. All rights reserved.)

In this study, MnO 2 /MWCNT hybrids, prepared using a solvothermal method, were coated onto Ni foam and then used as a cathode for tetrabromobisphenol A (TBBPA) degradation. The reaction was confirmed to exhibit the pseudo first-order kinetics. Compared with the original Ni foam cathode, the fabricated electrode exhibited higher catalytic activity, attributed to its strong cross-linking and ability to produce catalytic free radicals. Radical scavenger experiments revealed that O 2 - and OH were involved in the decomposition of TBBPA. The effects of current density, pH, catalyst dosage, and initial TBBPA concentration on removal efficiency were further studied. An optimal removal rate of 98.3% was achieved while the rate constant reached values up to 0.07293 min -1 and the debromination rate was more than 75.4% within 60 min. The electrode showed high catalytic performance and low catalyst loss after 10 cycles, indicating its excellent stability and reusability. The probable mechanism and pathway of TBBPA degradation were suggested based on the analysis of intermediate products. It could be inferred that the decomposition of TBBPA involved CC bond breaks (oxidation) and debromination (reduction). The MnO 2 /MWCNT-Ni foam could be a promising cathode material for electrochemical degradation of halogenated organic compounds., (Copyright © 2019 Elsevier B.V. All rights reserved.)

Enriched and bio-refractory soil heavy metals (SHMs) originate from the underground mineral, which supplies energy and materials for the development of economy and industry. Investigating soil metal contents and their adverse health impacts is the principal concern associated metal contaminated industrial areas, including both current assessments and future projections. In this research, we create a novel spatiotemporal model of SHMs prediction and risk characterization for future by citing a rigorous theory of industrial economics, and time series of activity intensity changes of various pollution sources are forecasted. The dynamic change of source contributions is quantitatively resolved and the mean SHMs concentrations are estimated by classical formulas for heavy metal accumulation. Human health risk in the future is described in a manner of time series. The results of the case study show that contribution rates of the five sources of the six metals change continuously over time. Pb, Cd and As assume the highest growth rates (400%, 500% and 165%), while Zn, Ni, Cr possesses relatively lower growth (< 130%), compared to their corresponding background values. Health risk of local sensitive population (children) is estimated at exceeding threshold in 2022 (non-carcinogenic) and 2012 (carcinogenic), and the upward trend will continue. Traffic emission, agriculture and household garbage are identified as major risky sources in the coming decades at the studied area, and improvement measures are recommended. Although a degree of uncertainties exists, the overall tendency is a conservative bias for chemical risk. Additionally, this paper is the first to explore a methodology of predicting future SHMs and associated human health risk, based on industrial economics and temporal source apportionment., (Copyright © 2018. Published by Elsevier Inc.)

An improved method was proposed which integrates the distribution of metal speciation simulated by chemical equilibrium model, different exposure models and average daily intake dose modified by analytic hierarchy process for human health risk assessment of metal species (MS). With the rapid development of economic and urbanization, the metals pollution had become more serious in industrial areas. Adverse effects of soil contaminants on human health in typical industrial area should be assessed to evaluate the risks of soils in these areas. The method was applied to study nickel (Ni) species health risks in soil of industrial areas. The pH possessed significant impact to determine distribution/existence and solubility of Ni species, followed by DOC. The non-carcinogenic risk (HQ) of Ni species were less than 1 in each sampling points, except Ni 2+ . In addition, the carcinogenic risk (CR) of different Ni species were less than 10 -6 , except for FANi and Ni 2+ ., (Copyright © 2018. Published by Elsevier Inc.)

In this research, a novel efficiency MnO 2 @Nano hollow carbon sphere (MnO 2 @NHCS) nanocomposite was prepared by one-pot hydrothermal reaction with KMnO 4 solution. The adsorption and oxidization performance of MnO 2 @NHCS were assessed by degradation of bisphenol A (BPA) at different conditions. The effect of dosage of MnO 2 @NHCS, pH, initial concentration of BPA, temperature and humic acid were investigated systematically. Moreover, the characterizations of MnO 2 @NHCS were measured by a series of techniques, such as XRD, FESEM, HRTEM, TGA and XPS. Notably, hollow structure of nano carbon sphere was still retained with uniform MnO 2 nanosheets covered. The results show that the removal rate of BPA was 95.3% within 10 min and BPA can be almost decomposed in 30 min under the optimal conditions. Additionally, the MnO 2 @NHCS remained stable and had a high regeneration efficiency (more than 85%) after 3 cycles (360 min). The reaction intermediates/products of oxidation of BPA were analyzed and the possible degradation pathways of BPA were proposed. These research results demonstrate that the MnO 2 @NHCS is a fleet and efficient material for BPA degradation in aqueous environment., (Copyright © 2018. Published by Elsevier B.V.)

The conventional risk assessment methods may be defective for more effective health risk assessment due to ignoring heavy metal species and the accuracy and integrity of sampling and analysis results. Using the accurate and integral data to quantify the human health effects of metal species can provide great support for more effective health risk assessment. This study presents a new methodology to optimize sampling and analysis results for implementing the spatial human health risk of heavy metal species in contaminated sites. The method integrated Entropy method and Inverse Distance to a Power (IDW) for obtaining the effective risk, and mapping the visual risk distribution of metal species. The results of its application with ingesting arsenic via oral route on adults showed that carcinogenic and non-carcinogenic risks of As were influenced by its species. The risk of HAsO 4 -2 , H 3 AsO 3 , H 2 AsO 4 - , H 2 AsO 3 - and AsS(OH)HS - exceeded threshold that was significantly harmful to human health in study area. This method broadened the scope of human health risk assessment and provided a basis for government policy-making and site remediation., (Copyright © 2018. Published by Elsevier B.V.)

In China, potential heavy metal hazard around abandoned lead-acid battery plant (ALBP) area has been a great concern but without detailed report. The distribution and sources of heavy metals in soils and so by risk assessment associated with ALBP are conducted in this contribution, based on geographies and statistics. Pb and Zn are quantitively identified to be still emitted from ALBP soil, and Cd as well As are from agricultural activity. We investigate vertical metal distribution, and fortunately find that metals migrate within limit of 40 cm below topsoil, which is higher than groundwater table. The visualized stable depths are Zn 40 cm, Pb, As 20 cm, and Cd 40 cm. The mapped pollution load index (PLI) suggests a high pollution level exists in ALBP soil. The estimation of potential ecological risk index (PERI) indicates a light ecological risk in studied area, while As and Cd mainly from agricultural activity possess 54% of total E ri . Health risk index (THI) is 0.178 for children, indicating non-cancer risks may be ignored in observed area. Though calculated risk is temporarily affordable, soil remediation and reduction of agricultural chemical reagents are recommended for preventing potential cumulative risk from further bioconcentration of heavy metals., (Copyright © 2018 Elsevier B.V. All rights reserved.)

The treatment of effluent containing Bisphenol A (BPA) was investigated experimentally using nitrogen-doped graphene aerogel (NGAs) as particle electrodes in a three-dimensional electrode reactor for the electrochemical treatment was studied. The effects of the cell voltage, pH, the ratio of NGAs mass to solution volume and repeated times on the removal efficiency were investigated. Compared with commercial carbon particle electrodes, the NGAs exhibited stronger activity to remove BPA simulated wastewater. For 15mgL -1 of BPA solution, the degradation rate of BPA exceeded 90% after treatment for only 30min under the optimum conditions. The COD Cr removal rate of BPA was 85%. Moreover, in the process of reused 50 times, the degradation rate of BPA can be kept in more than 85%. The COD Cr removal rate was stable at about 73%. The intermediate products of electrochemical degradation of BPA were identified by liquid chromatography-mass spectrometry liquid chromatography (LC-MS), and a probable BPA degradation pathway was proposed. It was considered that OH radicals by water electrolysis could constantly attack the aromatic ring to form various intermediates such as hydroxylated-BPA, isopropylphenol, hydroquinone, phenol and butantetraol, maleic acid, oxalic acid. These compounds were eventually mineralized by electrolysis into CO 2 and H 2 O., (Copyright © 2017 Elsevier B.V. All rights reserved.)

Objectives: Malocclusion may be corrected nonsurgically by mechanical tooth movement. The plasma protein profiles of human subjects receiving the first phase of orthodontic treatment were examined to test the hypothesis that application of mechanical stresses to teeth induces systemic proteomic alterations., Methods: Tandem mass tag-based liquid chromatography-mass spectrometry (LC-MS/MS) was used to examine systemic proteomic alterations in subjects undergoing controlled stress application (N=10) and in volunteers not receiving treatment (N=7) at 3 time intervals within 24h. Proteins differentially expressed by the tooth movement group were functionally analyzed with "Gene Ontology" (GO) and "Search Tool to Retrieve Interacting Genes/proteins" (STRING) softwares. Enzyme-Linked Immunosorbent Assay and Western-blot were used to validate the in vivo protein alterations. An in vitro model consisting of human periodontal ligament cells (hPDLCs) under compression was used to validate the force-responsive characteristics of galectin-3 binding protein (LGALS3BP)., Results: Sixteen out of the 294 proteins identified by LC-MS/MS were differentially expressed in the plasma of subjects receiving controlled mechanical stresses for moving teeth. Those proteins were clustered in biological processes related to acute inflammatory response and vesicle-related transportation. Serotransferrin, fibronectin and LGALS3BP were processed for confirmation in vivo; LGALS3BP was significantly increased in the tooth movement group. In vitro secretion of LGALS3BP in PDLCs was force-responsive., Conclusions: Regional application of mechanical stresses stimulates systemic proteomic changes. Because serum LGALS3BP is over-expressed in different systemic diseases, including cancer, further work is needed to examine how systemic up-regulation of LGALS3BP affects the progression of those diseases., (Published by Elsevier Ltd.)