The practical application of Cu(II)-catalyzed Fenton-like reaction (Cu(II)/H2O2) exhibits a low efficiency in the degradation of refractory compounds of wastewater. The impact of chloride ions (Cl-) on Fenton-like reactions have been investigated, but the influence mechanism is still unclear. Herein, the presence of Cl- (5 mM) significantly accelerated the degradation of benzoic acid (BA) under neutral conditions. The degradation of BA follows pseudo-first-order kinetics, with a degradation rate 7.3 times higher than the Cu(II)/H2O2 system. Multiple evidences strongly demonstrated that this reaction enables the production of reactive chlorine species (RCS) rather than HO• and high-valent copper (Cu(III)). The kinetic model revealed that Cl- could shift reactive species from the key intermediate (Cu(III)-chloro complexes) to RCS. Dichlorine radicals (Cl2•-) was discovered to play a crucial role in BA degradation, which was largely overlooked in previous reports. Although the reaction rate of Cl2•- with BA (k = 2.0 × 106 M-1 s-1) is lower than that of other species, its concentration is 10 orders of magnitude higher than that of Cu(III) and HO•. Furthermore, the exceptional efficacy of the Cu(II)/H2O2 system in BA degradation was observed in saline aquatic environments. This work sheds light on the previously unrecognized role of the metal-chloro complexes in production the RCS and water purification.

A significant knowledge gap exists regarding the impact of soil organic matter on the bioavailability of Ag2S-NPs (environmentally relevant forms of Ag-NPs) in soil-earthworm-plant systems. This study used two soils with varying organic matter content, both with and without earthworms, to investigate the bioavailability of Ag2S-NPs. The findings revealed an 80 % increase in Ag bioaccessibility to soybeans in soils with high organic matter content compared to soils with low organic matter. Additionally, the presence of earthworms significantly increased Cl concentrations from 24.3-62.2 mg L-1 to 80.1-147.2 mg L-1, triggering the elevated bioavailability of Ag. Interestingly, Ag2S-NPs eliminated the stimulative effects of earthworms on plant nutrient uptake. In the presence of earthworms, the high organic matter soil amended with Ag2S-NPs exhibited lower concentrations of essential elements (Ca, Cu, Fe, K, and P) in plant tissues compared to soils without earthworms. Our study presents evidence of the transformation of Ag2S-NPs into Ag-NPs across various soil solutions, resulting in the formation of Ag nanoparticle complexes. Particularly noteworthy is the significant reduction in particle sizes in soils incubated with earthworms and high organic matter content, from 85.0 nm to 40.2 nm. Notably, in the rhizosphere soil, a decrease in the relative abundance of nutrient cycling-related phyla was observed, with reductions of 18.5 % for Proteobacteria and 30.0 % for Actinobacteriota. These findings offer valuable insights into the biological and biochemical consequences of Ag2S-NP exposure on earthworm-mediated plant nutrient acquisition.

Elevated levels of atmospheric molecular chlorine (Cl2) have been observed during the daytime in recent field studies in China but could not be explained by the current chlorine chemistry mechanisms in models. Here, we propose a Cl2 formation mechanism initiated by aerosol iron photochemistry to explain daytime Cl2 formation. We implement this mechanism into the GEOS-Chem chemical transport model and investigate its impacts on the atmospheric composition in wintertime North China where high levels of Cl2 as well as aerosol chloride and iron were observed. The new mechanism accounts for more than 90% of surface air Cl2 production in North China and consequently increases the surface air Cl2 abundances by an order of magnitude, improving the model\'s agreement with observed Cl2. The presence of high Cl2 significantly alters the oxidative capacity of the atmosphere, with a factor of 20-40 increase in the chlorine radical concentration and a 20-40% increase in the hydroxyl radical concentration in regions with high aerosol chloride and iron loadings. This results in an increase in surface air ozone by about 10%. This new Cl2 formation mechanism will improve the model simulation capability for reactive chlorine abundances in the regions with high emissions of chlorine and iron.

Inorganic chlorine is susceptible to water and soil salinization due to its non-degradability and high mobility. To clarify the environmental risks associated with the active inorganic chlorine in municipal solid waste (MSW), the specific characteristics and contributions of inorganic chlorine in different MSW categories were investigated in this study. MSW samples were collected from eight representative waste classification residential areas in Hangzhou, China. It was found that the inorganic chlorine content in different MSW categories varied significantly (0-113 mg/g). Perishable waste, paper, and plastic were found to be the main sources of inorganic chlorine in MSW. A four-category classification system was used to quantify the contribution of inorganic chlorine from each waste category. It was found that the misclassification of inorganic chlorine contributions from perishable waste and other waste accounted for 51.96% and 48.04%, respectively. However, when correctly classified into the four-category system, their contributions were reduced to 67.14% and 30.65%, respectively. Therefore, MSW classification showed a significant reduction in the overall contribution of inorganic chlorine. The misclassification reduces the contribution of inorganic chlorine to 48.04%, while correct classification increases the reduction to 69.35%.

Cadmium (Cd) contamination in rice ecosystems posed a critical challenge to global food security and environmental health. This study aimed to unveil the key mechanisms trough hydroponic experiments by which chloride (Cl-) promoted the absorption and accumulation of cadmium (Cd) in rice plants. The findings elucidated that the addition of Cl- increased Cd uptake by rice roots (5.1 % ∼ 61 %), acting both directly by enhancing root morphology and indirectly through regulating of the main transporter genes of Cd. The study unveiled that Cl- addition significantly improves Cd bioavailability in roots, which was discernible through the augmentation of Cd concentration and proportion in subcellular fractions, coupled with elevated energy values in key cellular components. Moreover, Cl- addition further augmented the intricate process of Cd transport from roots to shoots (16.1- 86.7 %), which was mainly attributed to the underexpression of OsHMA3 and the decrease in the formation of sulfuhydryl substances. This research provides a comprehensive understanding of the complex mechanisms governing Cd dynamics in rice plants in the presence of Cl-. By elucidating these processes, our findings not only contribute to fundamental knowledge in plant metal uptake but also hold promising implications for mitigating Cd contamination in rice cultivation systems.

Low-pressure mercury lamps with high-purity quartz can emit both vacuum-UV (VUV, 185 nm) and UV (254 nm) and are commercially available and promising for eliminating recalcitrant organic pollutants. The feasibility of VUV/UV as a chemical-free oxidation process was verified and quantitatively assessed by the concept of H2O2 equivalence (EQH2O2), at which UV/H2O2 showed the same performance as VUV/UV for the degradation of trace organic contaminants (TOrCs). Although VUV showed superior H2O activation and oxidation performance, its performance highly varied as a function of light path length (Lp) in water, while that of UV/H2O2 proportionally decreased with decreasing H2O2 dose regardless of Lp. On increasing Lp from 1.0 to 3.0 cm, the EQH2O2 of VUV/UV decreased from 0.81 to 0.22 mM H2O2. Chloride and nitrate hardly influenced UV/H2O2, but they dramatically inhibited VUV/UV. The competitive absorbance of VUV by chloride and nitrate was verified as the main reason. The inhibitory effect was partially compensated by •OH formation from the propagation reactions of chloride or nitrate VUV photolysis, which was verified by kinetic modeling in Kintecus. In water with an Lp of 2.0 cm, the EQH2O2 of VUV/UV decreased from 0.43 to 0.17 mM (60.8% decrease) on increasing the chloride concentration from 0 to 15 mM and to 0.20 mM (53.5% decrease) at 4 mM nitrate. The results of this study provide a comprehensive understanding of VUV/UV oxidation in comparison to UV/H2O2, which underscores the suitability and efficiency of chemical-free oxidation with VUV/UV.

OBJECTIVE: Delayed cerebral ischemia (DCI)-induced cerebral infarction is a major cause of adverse neurological outcomes following aneurysmal subarachnoid hemorrhage (aSAH). This study aimed to investigate the relationship between postoperative serum electrolyte levels and DCI in patients with aSAH.
METHODS: We analyzed the data of patients with aSAH between 2015 and 2022. The patients were classified into two groups according to whether they experienced DCI. Electrolyte levels were categorized into three groups based on the normal ranges for electrolytes. Logistic regression models were used to study the relationship between electrolyte levels and DCI. Another logistic regression analysis was conducted to explore the relationship between the different severity levels of statistically significant indicators and DCI. A restrictive cubic spline model was adopted to assess the potential linear relationship between electrolytes and DCI. Subsequently, sensitivity analysis was performed to assess the impact of collinearity among ions. Finally, subgroup analysis was performed.
RESULTS: This study included 1,099 patients. Patients with hyperchloremia were more prone to DCI than those with normal chloride levels. Subsequently, excluding the population with hypochloremia, both mild and severe hyperchloremia were found to be associated with an increased risk of DCI compared with normal chloride levels. Within the framework of a restrictive cubic spline, our findings revealed an increased incidence of DCI (P for nonlinear = 0.735) as chloride levels increased. Sensitivity analysis revealed that patients with severe hyperchloremia were more susceptible to DCI.
CONCLUSIONS: This study found that patients with aSAH and postoperative hyperchloremia are more prone to developing DCI.

To reduce metal pipe corrosion, improve product quality, and meet zero liquid discharge (ZLD) criteria, managing chloride ion concentrations in industrial wastewaters from metallurgical and chemical sectors has become increasingly important. This review provides detailed information on the sources, concentration levels, and deleterious effects of chloride ions in representative industrial wastewaters, and also summarizes and discusses various chloride ion removal techniques, including precipitation, ion exchange, physical separation, and advanced oxidation (AOPs). Among these, AOPs are particularly promising due to their ability to couple with other technologies and the diversity of their auxiliary technologies. The development of dechlorination electrode materials by electro-adsorption (CDI) can be inspired by the electrode materials used in chloride ion battery (CIB). This review also provides insights into exploring the effective combination of multiple chloride removal mechanisms, as well as the development of environmentally friendly composite materials. This review provides a theoretical basis and development direction for the effective treatment and secondary utilization of chlorine-containing industrial wastewater in the future.

UNASSIGNED: Hypochloremia and red blood cell distribution width (RDW) play important roles in congestive heart failure (CHF) pathophysiology, and they were associated with the prognosis of CHF. However, the prognostic value of chloride combined with RDW in patients with CHF remains unknown.
UNASSIGNED: We retrospectively analyzed critically ill patients with CHF. The database was derived from the Medical Information Mart for Intensive Care IV v2.0 (MIMIC-IV-v2.0) database.
UNASSIGNED: In the final analysis, 5376 critically ill patients with CHF were included, and 2428 patients (45.2 %) experienced 5-year mortality. The restricted cubic spline model revealed a positive correlation between RDW and 5-year mortality, whereas chloride showed a U-shaped correlation with 5-year mortality. The median values of RDW and chloride were used to classify patients into four groups: high chloride/low RDW, low chloride/low RDW, high chloride/high RDW, and low chloride/high RDW. We observed the prognostic value of RDW combined with chloride in the Cox proportional hazard model, in predicting 5-year mortality, in-hospital mortality and 1-year mortality. Furthermore, we discovered that patients with chronic kidney disease (CKD) had a higher 5-year mortality risk than patients without CKD.
UNASSIGNED: We found the translational potential role of chloride combined with RDW in prioritizing patients at high risk for short- and long-term mortality in a cohort of critically ill patients with CHF. Prospective multicenter investigations are warranted to validate our results.

Manufactured sand, known for its artificial production, eco-friendliness, cost-effectiveness, and sustainability, serves as an excellent alternative to natural sand. Stone powder content plays a crucial role in determining the performance of manufactured sand, significantly enhancing concrete compaction and its ability to withstand environmental degradation. This study aims to explore the feasibility of using environmentally and economically advantageous manufactured sand in the construction of subway tunnel segments in coastal areas. It investigates the impact of stone powder content on the corrosion resistance of concrete made with manufactured sand under the combined influence of chloride salts and stray currents. The analysis covers corrosion tendencies, the post-rusting performance of reinforcement bars, the resistance of concrete to chloride transport, and microstructure properties, which are assessed through electron microscope scanning and mercury compression testing. The findings indicate that the corrosion resistance of manufactured sand concrete generally surpasses that of river sand concrete. Furthermore, stone powder content within the 3-8% range leads to a denser concrete microstructure, reduced porosity, lower free-chloride ion levels, increased polarization resistance of post-corrosion reinforcements, lower corrosion current density, and reduced mass loss of reinforcing bars. This research provides valuable theoretical support for promoting the use of environmentally friendly manufactured sand concrete in subway construction projects.