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2,4,6-Trichlorophenol (2,4,6-TCP) is extensively consumed in industrial production and may cause environmental damages. The effect of halide ions on the decomposition of 2,4,6-TCP has often been overlooked. In this study, the bromide ion was found to have a stronger negative impact on 2,4,6-TCP degradation than chloride ion in the O3 system, and led to the formation of adsorbable organic halogens (AOX). Kinetic modeling demonstrated that the concentration of various radicals was largely depended on the solution pH, and stronger basicity not only contributed to the mineralization of 2,4,6-TCP, but also inhibited the formation of halogenated by-products. Combining the intermediate identification and quantum chemical calculation, the degradation pathways of 2,4,6-TCP during ozone oxidation process were proposed. The toxicity test and ECOSAR simulation demonstrated that the acute toxicity of some 2,4,6-TCP degradation intermediates was relatively higher than their parent compound. With high concentrations of halide ions, the ozone-treated solution showed greater toxicity than the originator 2,4,6-TCP solution. These results illustrate that the ozone treatment of the halide-containing wastewater may cause potential ecological hazards and its application needs to be more cautious.

The humic-like substances were the main organic components in most wastewater (e.g. domestic sewage, toilet wastewater and landfill leachate). Two types of actual humic-like substances (fulvic acid (FA) and biologically treated landfill leachate (BTLL)) were selected to describe the changes in the properties of humic-like substances (complexation ability, aromaticity and mobility) during electrochemical oxidation. Meanwhile, the acute cytotoxicity of FA and BTLL was also tested by acute toxicological test of luminescent bacteria. The results showed that the consumption of coordinating groups such as phenolic groups and hydrogen bonds reduced the complexation ability of FA and BTLL. The functional groups were degraded with the removal order of quinone group, phenolic group and aromatic group, and finally realized the molecular saturation and aromaticity decrease for humic-like substances. The mobility of FA and BTLL was decreased because of the enhancement of hydrophobicity during electrolysis process. Furthermore, the available chlorine produced during electrochemical oxidation was the main acute cytotoxicity substance, therefore, it is necessary to remove it before discharge in order to reduce ecological risks. This study provides a basis for understanding and evaluating the electrochemical degradation process of humic-like substances in detail.

Climate change has become a great challenge for humanity. However, the current climate change mitigation measures, primarily concentrate on land, more or less neglecting the vital role of the ocean-based solutions. While the ocean is a crucial regulator of the global climate, ocean-based solutions could also play an essential role in climate change mitigation and policymaking. This paper developed an Ocean-based Solutions Carbon Reduction Assessment Model (OSCRAM) that addresses coastal ecosystems, ocean energy, marine transportation, fishery, and seabed to estimate the oceanic contribution to climate change mitigation. It has been applied to evaluate the capacity of carbon emission reduction through oceans in China. We found that the total contribution for carbon emission reduction was about 6.86 Tg CO2 per year, and it may reach 139.39 Tg in 2030 under the target scenario. The results indicated that the ocean has huge potential to reduce carbon emissions. The development of marine energy and low-carbon marine shipping may have more potential for emission reduction in China, and the government should also protect and restore coastal wetlands for their enormous carbon storage. It can also provide a reference for the globe and other nations in achieving emission reduction goals.

Minimal hepatic encephalopathy (MHE) is characterized as cognitive deficits including memory and learning dysfunctions after liver injuries or hepatic diseases. Our understandings of neurological mechanisms of MHE-associated cognitive syndromes, however, are far from complete. In the current study we generated a mouse MHE model by repetitive administrations of thioacetamide (TAA), which induced hyperammonemia plus elevated proinflammatory cytokines in both the general circulation and motor cortex. MHE mice presented prominent motor learning deficits, which were associated with excess dendritic spine pruning in the motor cortex under 2-photon in vivo microscopy. The pharmaceutical blockade of glucocorticoid receptor or suppression of its biosynthesis further rescued motor learning deficits and synaptic protein loss. Moreover, MHE mice presented microglial activation, which can be alleviated after glucocorticoid pathway inhibition. In sum, our data demonstrates corticosterone-induced microglial activation, synaptic over-pruning and motor learning impairments in MHE, providing new insights for MHE pathogenesis and potential targets of clinical interventions.

Humic-like substance-containing wastewater is the main type of wastewater. This study investigated the redox behavior of organic matter during the treatment process of humic-like substances by electrochemical oxidation as well as the feasibility of improving heavily polluted soil (using petroleum hydrocarbon contaminated soil as an example) with the effluent from different treatment levels. Molecular spectrum analysis and electrochemical analysis showed that the quinone and aromatic groups of the humic-like substances were degraded by electrochemical oxidation, directly leading to a decreased electron donating capability. Meanwhile, this process promoted the formation of protein-like substances and fulvic-like substances, and was accompanied by an improved electron accepting capability. Since the increasing amount of electron accepting capability was greater than the decreasing amount of electron donating capability throughout the whole process, the electrochemical oxidation process increased the total electron transfer capacity of the organic matter. In addition, bioinformatic analysis shows that the organic matter in the treated effluent enhanced the activity and abundance of dominant indigenous microorganisms in petroleum hydrocarbon contaminated soil, which is advantageous to the natural remediation of heavily polluted soils based on degradation by indigenous bacteria. This study provides a detailed basis for understanding the electrochemical degradation process of humic-like substances as well as the resource utilization of residual organic matter after electrochemical treatment of humic-like substance-containing wastewater.

The polyaspartic acid derivative compound was applicated in circulating cooling water system with high concentration multiple with the water quality of circulating cooling water system was characterized by higher hardness, higher alkalinity and higher corrosive ion content in order to solve the problem of scale and corrosion of the circulating cooling water system. The formulation of the polyaspartic acid derivative compound was determined to be PASP-AESA-ASP, ZnSO4, HPAA and BTA with the mass ratio of 15:4:6:0.1. The polyaspartic acid derivative compound had a good protective effect on A3 carbon steel in high-concentration-salt water and good biodegradability.

China is facing intense coastal eutrophication. Large-scale seaweed aquaculture in China is popular, now accounting for over 2/3’s of global production. Here, we estimate the nutrient removal capability of large-scale Chinese seaweed farms to determine its significance in mitigating eutrophication. We combined estimates of yield and nutrient concentration of Chinese seaweed aquaculture to quantify that one hectare of seaweed aquaculture removes the equivalent nutrient inputs entering 17.8 ha for nitrogen and 126.7 ha for phosphorus of Chinese coastal waters, respectively. Chinese seaweed aquaculture annually removes approximately 75,000 t nitrogen and 9,500 t phosphorus. Whereas removal of the total N inputs to Chinese coastal waters requires a seaweed farming area 17 times larger than the extant area, one and a half times more of the seaweed area would be able to remove close to 100% of the P inputs. With the current growth rate of seaweed aquaculture, we project this industry will remove 100% of the current phosphorus inputs to Chinese coastal waters by 2026. Hence, seaweed aquaculture already plays a hitherto unrealized role in mitigating coastal eutrophication, a role that may be greatly expanded with future growth of seaweed aquaculture.

This study presented a novel alternating-anode electrochemical system (AAES) based on single electrolytic cell for the treatment of nitrogen-containing refractory organic wastewater (NOW). The core of AAES lies in the alternating working of iron anode and DSA anode to integrate different electrochemical processes. The biologically treated landfill leachate (BTLL) was selected as a practical NOW for assessing the performance of AAES. The results indicated that after 140 min of electrolytic reaction, the removal efficiency of chemical oxygen demand and total nitrogen (TN) using AAES was found to be 76.9 and 98.9%, respectively. The main component of dissolved organic matter (DOM) in BTLL included humic-like substances, which could be degraded into small-molecule DOM, such as fulvic-like substances and protein-like substances, by available chlorine and hydroxyl radicals present in AAES. Cathode reduction (NOx−-N → NH4+–N and N2) under iron anode and indirect oxidation (NH4+–N → N2) under DSA anode were the main pathways to remove TN from NOW. Owing to the redox conditions created by the alternating anodes, the main stable crystalline forms of precipitates obtained from AAES were Fe3O4 and γ-Fe2O3, which could be separated by using the external magnetic field. The findings of this study may provide a feasible solution for the advanced electrochemical treatment of NOW in a single electrolytic cell as well as rapid separation of precipitates.