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As the producer of reactive oxygen species (ROS), both lead (Pb) and paraquat (PQ) can generate serious oxidative stress in target organs which result in irreversible toxic effects on organisms. They can disturb the normal catalytic activities of many enzymes by means of different toxicity mechanism. The changed responses of enzymes are frequently used as the biomarkers for indicating the relationship between toxicological effects and exposure levels. In this work, goldfish was exposed to a series of test groups containing lead and paraquat in the range of 0.05–10 mg/L, respectively. Four hepatic enzyme activities, including 7-ethoxyresorufinO-deethylase (EROD), 7-benzyloxy-4-trifluoromethyl-coumarin-O-debenzyloxylase (BFCOD), glutathione S-transferase (GST) and UDP-glucuronosyltransferase (UGT) were determined after 1, 7, 14, 28 days exposure. The results showed that the activities of EROD and BFCOD in fish were significantly inhibited in response to paraquat at all exposure levels during the whole experiment. Similarly, the inhibitory effects of lead exposure on BFCOD activity were found in our study, while different responses of lead on EROD were observed. There were no significant differences on EROD activity under lower concentrations of lead (less than 0.1 mg/L) before 14 days until an obvious increase was occurred for the 0.5 mg/L lead treatment group at day 14. Furthermore, lead showed stronger inhibition on GST activity than paraquat when the concentrations of the two toxicants were more than 0.5 mg/L. However, the similar dose and time-dependent manners of UGT activity were found under lead and paraquat exposure. Our results indicated that higher exposure levels and longer accumulations caused inhibitory effects on the four enzymes regardless of lead or paraquat stress. In addition, the responses of phase I enzymes were more sensitive than that of phase II enzymes and they may be served as the acceptable biomarkers for evaluating the toxicity effects of both lead and paraquat. [ABSTRACT FROM AUTHOR]

A method using derivatization and supercritical fluid extraction coupled with gas chromatography was developed for the analysis of dimethylarsinate, monomethylarsonate and inorganic arsenic simultaneously in solid matrices. Thioglycolic acid n-butyl ester was used as a novel derivatizing reagent. A systematic discussion was made to investigate the effects of pressure, temperature, flow rate of the supercritical CO2, extraction time, concentration of the modifier, and microemulsion on extraction efficiency. The application for real environmental samples was also studied. Results showed that thioglycolic acid n-butyl ester was an effective derivatizing reagent that could be applied for arsenic speciation. Using methanol as modifier of the supercritical CO2 can raise the extraction efficiency, which can be further enhanced by adding a microemulsion that contains Triton X-405. The optimum extraction conditions were: 25 MPa, 90°C, static extraction for 10 min, dynamic extraction for 25 min with a flow rate of 2.0 mL/min of supercritical CO2 modified by 5% v/v methanol and microemulsion. The detection limits of dimethylarsinate, monomethylarsonate, and inorganic arsenic in solid matrices were 0.12, 0.26, and 1.1 mg/kg, respectively. The optimized method was sensitive, convenient, and reliable for the extraction and analysis of different arsenic species in solid samples. [ABSTRACT FROM AUTHOR]

Reusing industrial waste may have impressive potential environmental benefits, especially in terms of the total life cycle, and life cycle assessment (LCA) has been proved to be an effective method to evaluate industrial symbiosis (IS). Circular economy and IS have been developed for decades and have been successful in China. However, very few studies about the environmental benefit assessment of IS applied by LCA in China have been conducted. In the current article, LCA was used to evaluate the environmental benefits and costs of IS, compared with a no-IS scenario for four environmental impact categories. The results showed that four environmental benefits were avoided by the 11 symbiosis performances, namely, 41.6 thousand TJ of primary energy, 4.47 million t COe of greenhouse gasses, 19.7 thousand t SOe of acidification, and 81.1 t POe of eutrophication. Among these IS performances, the comprehensive utilization of red mud produced the most visible benefit. The results also present that energy conservation was the distinctive feature of IS in China. [ABSTRACT FROM AUTHOR]

The available energy resources are being depleted worldwide. Industrial symbiosis (IS) provides a promising approach for increasing the efficiency of energy utilization, with numerous studies reporting the superiority of this technology. However, studies quantifying the energy-saving efficiency of IS remain insufficient. This paper proposes an index system for the quantitative evaluation of the energy-saving efficiency of IS. Both energy-saving and financial indexes were selected, the former include the IS energy-saving index, the contribution rate of energy saved through IS, fractional energy savings, and cut rate of energy consumption per total output value; and the latter include the IS investment payback period, IS input-output ratio, net present value (NPV), and internal rate of return (IRR) of IS. The proposed methods were applied to a case study on the XF Industrial Park (XF IP), in the city of Liaocheng in Shandong Province of China. Three energy-saving channels using IS were found in the XF IP: (a) utilizing the energy of high-temperature materials among industrial processes, (b) recovering waste heat and steam between different processes, and (c) saving energy by sharing infrastructures. The results showed that the energy efficiency index of IS was 0.326, accounting for 34.6 % of the comprehensive energy-saving index in 2011, and the fractional energy-savings were 12.42 %. The index of energy consumption per total industrial output value varied from 90.9 tce/MRMB to 51.6 tce/MRMB. Thus, the cut rate of energy consumption per total industrial output value was 43.42 %. The average values of the IS input-output ratio was 406.2 RMB/tce, 57.2 % lower than the price of standard coal. Static investment payback period in the XF IP was 8.5 months, indicating that the XF IP began to earn profit 8.5 months after the construction of all IS modes. The NVP and IRR of each IS mode in the XF IP were greater than zero, with average values equal to 1,789.96 MRMB and 140.96 %, respectively. The computation result for each indicator revealed that IS could lead to the use of energy with high efficiency and lighten the financial burden of enterprises in the XF IP. And the proposed index system may help IPs and EIPs to make strategic decisions when designing IS modes. [ABSTRACT FROM AUTHOR]

For many water-intensive process industries, process integration approaches can reduce both freshwater consumption and effluent generation by water reuse/recycle. Based on Source/Sink representation, this paper presents a mathematical programming model for the design of water network to achieve the minimum water targets. Discharged water from each unit as well as the fresh feed is considered as water sources, whereas units that accept water are considered as sinks. The method combines water-using processes with water treatment operations into a single network. Embedding all the network configurations of source-sink matches, the model is formulated as a linear programming (LP) with flowrate and concentration constraints, which is then optimized by using commercial software LINGO v.9. Finally, a case study of a paper mill is implemented to show the effectiveness of the model. An 18% reduction of freshwater usage and optimal water network are obtained. [ABSTRACT FROM AUTHOR]

Iron tailings are generated in large amounts due to the extensive mining activities, leading to the large-scale land occupation, serious environmental pollution and high ecological risks. Therefore, there is an urgent need to develop economic and effective technologies for the large scaled utilization of tailings. In this study, 1132.8 m2 field experiments were carried out for 105 days in Anshan iron mine of Liaoning Province, with the aims to investigate the application and performance of sustainable utilization technologies on iron tailings, including amendments (A1, A2, A3), plants (P1, P2, P3), microorganisms (M1, M2, M3), and amendment-plant-microorganism (JT1, JT2, JT3). The results show that the applied utilization technologies can not only reduce the bulk density and pH of tailings but also increase tailing moisture and porosity. The tailing fertility gradually reached the medium and even high levels, thereby providing plants with relatively ideal growth environment. Besides, the growth of soil bacterial, fungal and actinomycete populations were stimulated to varying degrees with the utilization technologies, especially for M1 treatment. The evaluation results suggest that the performance of 12 utilization technologies were in the order of M1 > P3, JT1, A2 > JT3, A1, A3 > M3, P1 > M2 > P2 > JT2. The results of this study can provide valuable insights to improve the management of tailings so that long term effects of mining activities can be mitigated. [Display omitted] [ABSTRACT FROM AUTHOR]

• A dynamic bottom-up MFA model is established to estimate in-use stocks of Li and Co in LIBs. • The total consumption of Li and Co was 61.8 kt and 247.6 kt in China from 2000−2018. • In-use stocks of Li and Co increased from 0.03 kt and 0.2 kt to 17.5 kt and 31.0 kt. • Electric automobiles replaced mobile phones and laptops as a major consumer of Li and Co from 2015. Lithium and cobalt are key raw materials for the production of lithium-ion batteries (LIBs). This study illustrates the evolution of lithium and cobalt metabolism in the LIB system in China by applying dynamic bottom-up material flow analysis. From 2000 to 2018, the consumption of LIBs increased from 1.4 kt (0.2 GWh) to 547.1 kt (102.9 GWh) in China. The cumulative consumption of lithium and cobalt for LIB production was 61.8 kt and 247.6 kt, respectively. From 2000 to 2014, the popularization of mobile phones and laptops promoted the consumption of lithium and cobalt. After 2015, electric automobiles gradually became a major driving force for the growth of lithium and cobalt consumption. The increasing use of LIBs resulted in the growth of in-use stocks of lithium and cobalt from 0.03 kt and 0.2 kt in 2000 to 17.5 kt and 31.0 kt in 2018, respectively. Meanwhile, end-of-life (EOL) LIBs were rapidly generated, with the increase from 0.1 kt/yr to 110.7 kt/yr. In 2018, 0.4 kt of lithium and 3.1 kt of cobalt were recovered from these EOL LIBs in 2018, which provided 4.2% and 12.8% of the lithium and cobalt supplies for new LIBs, respectively. Besides, 1.1 kt of EOL LFP batteries were used in echelon utilization in 2018. Based on the results, some recommendations were proposed for the sustainable development and waste management of LIB industries, including encouraging the innovation of LIB technology and combining multiple technologies, strengthening closed-loop management of LIBs, and promoting echelon utilization of EOL LIBs. [ABSTRACT FROM AUTHOR]

Huangshui River, a tributary of the upper Yellow River, is one of the most important water resources conservation and recharge area of the Yellow River. In recent decades, agricultural cultivation and urbanization in Huangshui River Basin led to soil contamination. The Huangshui River were also seriously polluted, all at Grade V for many years before. Quantitative assessment model of heavy metal contamination in environment can provide guidance for regional policy making. In the present study, the distribution characteristics of potentially toxic metals in soil of Huangshui River plateau region were studied, and the contamination risk of heavy metals was evaluated. 113 top-soil samples were collected and surveyed for toxic element concentrations. The high coefficient of variation (CV) of Cd (274.5), Co (225.1), Pb (115.9), Hg (139.3) showed the high dispersion of heavy metal. The study built the distribution model of species sensitivity in the study area and calculated the environmental non-effect concentration (NOEC). Meanwhile, the ecological risk based on the environmental non-effect concentration and the background value (BC) was compared to explore the difference. The RI result based on the background value showed a maximum value of 1491, which is much higher than the ecological risk 520 based on the SSD result. The results indicated that there are some limitations in the risk evaluation of selecting the standard value or background value as the evaluation factor, which may exaggerate the risk. At the same time, the method was also suitable for the soil in other regions under the premise that the sensitivity distribution model could be constructed. Health risks of adults and children were made with the health risk assessment model for the two land use types. The hazard index (HI) of element Cr for children was 1.06, which was potential non-carcinogenicity to human health. The CR of Cd, Cr and As were above 10E-6 for children and adults, which was viewed as a risk range. This study established a credible risk assessment system, which can provide guidance for soil and ecological health development and policy making. [ABSTRACT FROM AUTHOR]

• Solution processable PIMs were synthesized and applied for silver removal. • High Ag+ capacity and selectivity were obtained. • Excellent antibacterial ability was achieved as surface coatings. • Dissolution-separation-precipitation (DSP) approach was proven for adsorbent regeneration. • Distinguished renewability after fouling. Silver ions (Ag+) in waterways pose a growing threat to the environment and living organisms. Achieving an effective and green process for Ag+ removal requires an adsorbent with excellent specificity for silver ions and easy recoverability after fouling or blocking. However, this remains a major challenge. To address this concern, we developed a high-performance adsorbent by grafting polymers of intrinsic microporosity (PIM) with thioamide groups. This thioamide-modified PIM (TPIM-1) adsorbent exhibited an exceptional adsorption capacity of 656 mg g−1 and high selectivity (distribution coefficient of 833.3 mL g−1, selectivity coefficient of 346 over Cd2+) for aqueous Ag+ removal. TPIM-1 also features good solubility in selected solvents, allowing regeneration through a dissolution separation precipitation (DSP) procedure once fouling or blocking occurs. Over 80 % of the adsorption capacity was recovered after nine continuous regeneration cycles, showcasing potential cost-effective reusability. Density Functional Theory (DFT) results reveal that the grafted thioamide groups play a critical role in selective Ag+ adsorption, with a binding energy of 54 kcal mol−1. In addition, the Ag+-loaded PIM-coated glass surface showed excellent antibacterial ability, inhibiting the growth of Bacillus subtilis and E. coli. This study provides a viable strategy for the development of a low-carbon footprint silver removing adsorbent from wastewater. [ABSTRACT FROM AUTHOR]

In this study, sulfur-containing iron carbon nanocomposites (S@Fe-CN) were synthesized by calcining iron-loaded biomass and utilized to activate persulfate (PS) for the combined chemical oxidation and microbial remediation of petroleum-polluted soil. The highest removal efficiency of total petroleum hydrocarbons (TPHs) was achieved at 0.2% of activator, 1% of PS and 1:1 soil-water ratio. The EPR and quenching experiments demonstrated that the degradation of TPHs was caused by the combination of 1O 2, ·OH, SO 4 ·-, and O 2 ·-. In the S@Fe-CN activated PS (S@Fe-CN/PS) system, the degradation of TPHs underwent two phases: chemical oxidation (days 0 to 3) and microbial degradation (days 3 to 28), with kinetic constants consistent with the pseudo-first-order kinetics of chemical and microbial remediation, respectively. In the S@Fe-CN/PS system, soil enzyme activities decreased and then increased, indicating that microbial activities were restored after chemical oxidation under the protection of the activators. The microbial community analysis showed that the S@Fe-CN/PS group affected the abundance and structure of microorganisms, with the relative abundance of TPH-degrading bacteria increased after 28 days. Moreover, S@Fe-CN/PS enhanced the microbial interactions and mitigated microbial competition, thereby improving the ability of indigenous microorganisms to degrade TPHs. [Display omitted] • PS activation by S@Fe-CN is better than Fe-CN for remediation of oil-polluted soil. • Biochar and S species in S@Fe-CN protect microbial abundance. • TPHs degrading bacteria that appear after chemical oxidation can also remove TPHs. • The addition of S@Fe-CN enhances microbial associations in soil. [ABSTRACT FROM AUTHOR]

Nitroaromatic compounds (NACs) are widely used in the manufacturing industry and are known for their high toxicity and mutagenicity. Convenient and highly sensitive detection of NACs is of great importance for human health and environmental protection. Herein, robust conjugated microporous polymer (CMP) films with a thickness of only 50 nm were prepared directly on the electrode surface by one-step electro-oxidative co-polymerization of N -(6-Hydroxyhexanyl) (CbzC 6 -OH) and 1,3,5-tris(N -carbazolyl) benzene (TCB). The resulting CMP presents a high specific surface area (S BET 687 m2 g−1) and enhanced NACs electro-sensitivity, with detection limits of 0.024 μM for nitrobenzene (NB) and 0.026 μM for 2,4,6-trinitrotoluene (TNT), an order of magnitude lower than the bare GCE. Moreover, the sensor exhibits a wide linear detection range of 0.1–100 μM, highlighting its potential for sensitive and quantitative detection of nitroaromatics. [Display omitted] • Electro-copolymerization strategy was developed for conjugated microporous polymer (CMP) film preparation. • Robust CMP film with a thickness of 50 nm was prepared in high quality. • Wide linear detection range of 0.1–100 μM towards NB and TNT was achieved. • Low detection limits of 0.024 μM NB and 0.026 μM for TNT were achieved. [ABSTRACT FROM AUTHOR]