Correlation Analysis of the Carboxyl and Carbonyl Groups of Natural Organic Matter and the Formation Potential of Trihalomethanes and Chloral Hydrate.

Natural organic matter (NOM) has always been considered the main precursor of disinfection by-products (DBPs) during the chlorine disinfection of drinking water. This research focuses on investigating the correlation between the functional group (carboxyl and carbonyl groups) content of NOM and the formation of trichloromethane (TCM) and chloral hydrate (CH). The quantitative determination of carboxyl groups, carbonyl groups, TCM, and CH were conducted during the drinking water treatment processes with different coagulant dosages and with/without pre-oxidation by KMnO4 or NaClO. The most appropriate coagulant for the removal of conventional components was polyaluminum chloride (PAC), and the dosage was 110 mg/L. Up to 43.7% and 14.5% of the carboxyl and carbonyl groups, respectively, were removed through the coagulation and sedimentation processes, which can be enhanced by increasing PAC dosage. The filtration process further increased the removal rates of these two functional groups to 59.8% and 33.5%, respectively. The formation potential of the TCM and CH decreased as the PAC dosage increased. Pre-oxidation by KMnO4 (0.8-1.0 mg/L) effectively controlled the formation of DBPs while increasing the carboxyl and carbonyl group content. Pre-oxidation by NaClO decreased the formation of TCM rather than CH, and a suitable amount (0.5-1.0 mg/L) decreased the carboxyl and carbonyl groups. It was found that there was a good linear correlation between carboxyl groups and TCM and CH. The linear fit R2 values of the carboxyl groups to TCM and CH were 0.6644 and 0.7957, respectively. The linear fit R2 values of the carbonyl groups to TCM and CH were 0.5373 and 0.7595, respectively.

Tumor-suppressive microRNA-10a inhibits cell proliferation and metastasis by targeting Tiam1 in esophageal squamous cell carcinoma.

Aberrant microRNAs (miRNAs) expressions could contribute to the progression of numerous cancers, including esophageal squamous cell carcinoma, while miR-10a participates in multiple biological processes on cancers. However, the molecular mechanism of miR-10a in esophageal squamous cell carcinoma (ESCC) has not been investigated. Herein, miR-10a was significantly reduced in ESCC clinical tissues and ESCC cell lines (EC109 and TE-3). In addition, immunohistochemistry indicated that the expressions of α-SMA, Ki-67, and PCNA in tumor tissues were higher than that of controls. In vitro, overexpression of miR-10a dramatically suppressed cell proliferation and enhanced cell apoptosis, while the decrease of miR-10a expressed the opposite outcome. Specially, overexpression of miR-10a caused a G0/G1 peak accumulation. Moreover, miR-10a also negatively regulated ESCC cell migration and invasion. Furthermore, targetscan bioinformatics predictions and the dual-luciferase assay confirmed that Tiam1 was a direct target gene of miR-10a. The statistical analysis showed Tiam1 was negatively in correlation with miR-10a in ESCC patient samples. And silencing Tiam1 could lead to a decline on cell growth, invasion, and migration in ESCC cell lines, while it could enhance cell apoptosis and cause a G0/G1 peak accumulation. In vivo, it revealed that miR-10a notably decreased the tumor growth and metastasis in xenograft model and pulmonary metastasis model. And it showed a lower expressions of Tiam1 in the miR-10a mimics group by immunohistochemistry. Taken together the results, they indicated that miR-10a might function as a novel tumor suppressor in vitro and in vivo via targeting Tiam1, suggesting miR-10a to be a candidate biomarker for the ESCC therapy.

Protective properties of Huperzine A through activation Nrf2/ARE-mediated transcriptional response in X-rays radiation-induced NIH3T3 cells.

Huperzine A (HupA), derived from Huperzia Serrata, has exhibited a variety of biological actions, in particular neuroprotective effect. However, the protective activities of HupA on murine embryonic fibroblast NIH3T3 cells after X-rays radiation have not been fully elucidated. Herein, HupA treatment dramatically promoted cell viability, abated a G0/G1 peak accumulation, and ameliorated increase of cell apoptosis in NIH3T3 cells after X-rays radiation. Simultaneously, HupA notably enhanced activities of anti-oxidant enzymes, inhibited activity of lipid peroxide, and efficiently eliminated production of reactive oxygen species in NIH3T3 cells after X-rays radiation. Dose-dependent increase of antioxidant genes by HupA were associated with up-regulated Nrf2 and down-regulated Keap-1 expression, which was confirmed by increasing nuclear accumulation, and inhibiting of degradation of Nrf2. Notably, augmented luciferase activity of ARE may explained Nrf2/ARE-mediated signaling pathways behind HupA protective properties. Moreover, expression of Nrf2 HupA-mediated was significant attenuated by AKT inhibitor (LY294002), p38 MAPK inhibitor (SB202190) and ERK inhibitor (PD98059). Besides, HupA-mediated cell viability, and ROS production were dramatically bated by LY294002, SB202190, and PD98059. Taken together, HupA effectively ameliorated X-rays radiation-induced damage Nrf2-ARE-mediated transcriptional response via activation AKT, p38, and ERK signaling in NIH3T3 cells.

Interface Mechanisms of Catalytic Ozonation with Amorphous Iron Silicate for Removal of 4-Chloronitrobenzene in Aqueous Solution.

Iron silicate was synthesized and characterized as an efficient ozonation catalyst. Results indicated that iron silicate is a microporous material with poor crystallinity. Fe-O-Si and Fe-O bonds were observed on its surface. The Fe-O bonds belonged to α-Fe2O3. Heterogeneous catalytic ozonation test was performed in batch reaction mode, and 4-chloronitrobenzene was used as model organic compounds. Amorphous iron silicate exhibited high catalytic activity, ozone utilization efficiency, and stability in catalytic ozonation. Hydroxyl radical was the dominant oxide species in this process. The reaction mechanism at the solid-water interface indicates that Fe-Si binary oxides on iron silicate surface inhibited ozone futile decomposition. This behavior resulted in enhanced probability of the reaction between ozone and α-Fe2O3 on the iron silicate surface to generate hydroxyl radicals, which promoted 4-chloronitrobenzene removal in aqueous solution.

Simultaneous regeneration of activated carbon and removal of adsorbed atrazine by ozonation process: From laboratory scale to pilot studies.

A novel treatment technique by coupling granular activated carbon (GAC) adsorption and ozone regeneration was constructed for long-lasting water decontamination. The GAC adsorption showed high performance for atrazine (ATZ) removal (99.9 %), and the ozone regeneration ensured the recyclability of GAC for water purification. The regeneration process was evaluated via several paths to assist the efficient adsorption process. Employing ozone micro-nano bubbles (O3-MNBs) for regenerating GAC showed superior performance compared to traditional ozone. Meantime, inhibiting the formation of bromate (BrO3-). ATZ adsorption process suffered from the pore-filling, hydrogen bonding effect and π-π EDA interaction. The surface phenolic hydroxyl group, carboxyl group and pyridine nitrogen benefitted the triggering of ozone to generate reactive oxygen species, and regenerate the GAC surface. The superior performance of the adsorption and regeneration process was verified via a long-term running by a pilot study. It significantly improved the removal of organic micropollutants, UV254 and permanganate index. Additionally, the intermittent O3-MNBs regeneration process resulted in efficient decontamination within the pores structure of GAC, which also effectively preserved the pore structure from destruction. For actual application, the cost of water production can be saved around 0.63 kWh m-3. This work proposed new ideas and theoretical support for economic water production.

Nationwide meta-analysis of microplastic distribution and risk assessment in China's aquatic ecosystems, soils, and sediments.

Microplastic (MP) accumulation has recently become a pressing global environmental challenge. As a major producer and consumer of plastic products, China's MP pollution has garnered significant attention from researchers. However, accurate and comprehensive investigations of national-level MP pollution are still lacking. In this study, we systematically collated a national MP pollution dataset consisting of 7766 water, soil, and sediment sampling sites from 544 publicly published studies, revealing the spatiotemporal distribution and potential risks of MP pollution in China. The results indicate that MP distribution is influenced by various regional factors, including economic development level, population distribution, and geographical environment, exhibiting considerable range and complexity. MP concentrations are generally higher in economically prosperous areas, but the degree of pollution varies significantly across different environmental media. Given the uncertainty and lack of standardized data in traditional microplastic risk assessment methods, this article highlights the urgency of developing a comprehensive big data and artificial intelligence (AI)-based regulatory framework. This work provides a substantial amount of accurate MP pollution data and offers a fresh perspective on leveraging AI for microplastic pollution regulation.

Characteristics and disinfection by-product formation potential of dissolved organic matter in reservoir water in cold area.

The severe cold in winter with harsh natural conditions in Northeastern China seriously affect the water quality of the reservoir, showing the increased content and more complex types of organic matter, which brings severe challenges to the control of disinfection by-products (DBPs) in drinking water treatment with reservoir water as the water source. In this study, the fractions of dissolved organic matter (DOM) in source water at before ice formation period (P1), ice-age period (P2), and ice begin to melt period (P3) were separated by membrane separation technology. Subsequently, the contributions of DOM fractions with different molecular weights (MW) to DOC, UV254, and SUVA254, and their disinfection by-product formation potential (DBPFP) were evaluated. Although DOM with high MW (5-10 kDa) contributed the most to dissolved organic carbon (DOC) and UV254, but the contribution of DOM with low MW (0-1 kDa) to DBPs formation could not be ignored, especially during ice-age period. There was no significant difference in the total numbers of DOM formula belonged to low MW fraction at these three periods, mainly including lignin, followed by N-containing saturated compounds and tannins. Additionally, redundancy analysis revealed that DOC and UV254 as the predictors had good correlation with DBPFP, while SUVA254 could not be used as a single indicator to predict the generation potential of DBPs, and could be used as the prediction factors together with AImodwa parameter closely related to DBPFP. The study provided key information for controlling the DBPs formation of DOM in water, especially in the ice-age period, and provided the theoretical basis for water plant production.

Formation pathway of disinfection by-products of lignin monomers in raw water during disinfection.

In this study, the dissolved organic matter (DOM) profiles of water samples from a water source in northeastern China were analyzed by high-resolution mass spectrometry (HRMS), and its changes after chlorination were investigated. The results showed that lignin substances accounted for a significant proportion in DOM and chlorinated products and were the main precursors of disinfection by-products (DBPs). During disinfection, macromolecular DOM was transformed into small molecules, and lignin substances have the most obvious and complex changes in reaction. Two lignin monomers 4-propylphenol (4PP) and 4-propylguaiacol (4PG) were used as model compounds to study their reaction kinetics and degradation pathways during disinfection. The degradation of both lignin monomers conformed to pseudo-first-order reaction kinetics, and the reaction rate constant of 4PG was higher than that of 4PP. The effects of chlorine dosage, pH and temperature on the degradation reaction kinetics of two lignin monomers were investigated. The degradation rates of 4PP and 4PG increased with increasing chlorine dosage, pH and temperature. The two monomers showed similar properties in the chlorination degradation process, and generated multiple intermediates, which were mainly transformed into small molecules by chlorine electrophilic substitution and nucleophilic substitution, and further generated DBPs.

Non-radical dominated degradation of bisphenol S by peroxymonosulfate activation under high salinity condition: Overlooked HOCl, formation of intermediates, and toxicity assessment.

Extensive studies revealed that Cl- could inhibit the removal of targeted pollutants under low Cl- conditions in the peroxymonosulfate (PMS) system. However, the enhanced effect of Cl- has always been overlooked under high Cl- conditions. Here, we find that high concentration of Cl- played a critical role in bisphenol S (BPS) degradation by activating PMS using 16%-CoFe2O4@PAL (16%-CFO@PAL). The removal of BPS was sharply enhanced after introducing 0.5 and 1.0 M Cl-, and the corresponding kobs increased to 0.922 min-1 and 1.103 min-1, which was 6-fold and 7-fold higher than the control (0.144 min-1), respectively. HOCl was demonstrated as the dominant species for removing BPS in 16%-CFO@PAL/PMS system under high Cl- circumstances. The typical chlorinated BPS intermediates were identified, which showed higher eco-toxicity than BPS. The chlorinated byproducts along with their toxicity could be effectively eliminated after 30 min. The possible formation mechanism of chlorinated products was further revealed by theoretical calculations. Toxicity assessment experiments showed that BPS significantly affected hormone levels of zebrafish and showed toxicity on the testis and liver of zebrafish, which could be reduced using 16%-CFO@PAL/PMS system. This study attracts attention to the overlooked HOCl in PMS-based processes under high salinity conditions.

Regrowth potential of chlorine-resistant bacteria in drinking water under chloramination.

The regrowth of chlorine-resistant bacteria in drinking water can deteriorate water quality. The study evaluated the relationship between organic carbon and the regrowth potential of chlorine-resistant bacteria remaining in chloraminated water samples. The results showed that the community structure of bacteria changed with the increase of chloramine dosage. The order in which organic carbon utilized by bacteria was affected by the composition of bacterial community. The biodegradable dissolved organic carbon (BDOC), assimilable organic carbon (AOC), bacterial regrowth potential (BRP) and total cell concentration (TCC) in cultivated water sample after disinfection with 1.8 mg/L chloramine increased form 0.22 mg/L, 33.68 µg/L, 2.70 × 105 cells/mL and 3.48 × 104 cells/mL before cultivation to 1.20 mg/L, 193.90 µg/L, 4.74 × 105 cells/mL and 1.46 × 105 cells/mL, respectively. The increase of TCC did not result in the decrease of BDOC, AOC and BRP in the cultivated water samples. The results showed that other biodegradable organic carbon in chloraminated water samples assimilated by residual chlorine-resistant bacteria besides AOC, BDOC, and organic carbon assimilated by indigenous bacteria. AOC, BDOC, and BRP indicators used to characterize the biostability of drinking water were not enough to accurately assess the regrowth potential of chlorine-resistant bacteria remaining in drinking water. It is suggested to supplement the index of TCC in cultivated water samples, which might be able to more accurately evaluate the regrowth potential of chlorine-resistant bacteria remaining in drinking water.

N-nitrosodimethylamine formation during oxidation of N,N-dimethylhydrazine compounds by peroxymonosulfate: Kinetics, reactive species, mechanism and influencing factors.

This study found that peroxymonosulfate (PMS) oxidation without activation has the potential to generate a suspected human carcinogen, N-nitrosodimethylamine (NDMA), in water containing N,N-dimethylhydrazine compounds. Considerable amounts of NDMA formed from three compounds by PMS oxidation were observed. 1,1,1',1'-Tetramethyl-4,4'-(methylene-di-p-phenylene) disemicarbazide (TMDS), which is an industrial antiyellowing agent and light stabilizer, was used as a representative to elucidate the kinetics, transformation products, mechanism and NDMA formation pathways of PMS oxidation. TMDS degradation and NDMA formation involved direct PMS oxidation and singlet oxygen (1O2) oxidation. The oxidation by PMS/1O2 was pH-dependent, which was related to the pH-dependent characteristics of the reactive oxygen species and intermediates. The degradation mechanism of TMDS mainly included the side chain cleavage, dealkylation, and O-addition. NDMA was generated from TMDS mainly via O-addition and 1,1-dimethylhydrazine (UDMH) generation. The cleavage of amide nitrogen in O-addition products and primary amine nitrogen in UDMH are likely the key steps in NDMA generation. The results emphasized that the formation of harmful by-products should be taken into account when assessing the feasibility of PMS oxidation.

Enhanced degradation of iohexol in water by CuFe2O4 activated peroxymonosulfate: Efficiency, mechanism and degradation pathway.

Iohexol as an iodinated X-ray contrast agent is widely used, and it is the potential precursor for toxic iodinated disinfection by-products in the disinfection process. In this study, a series of CuFe2O4 catalysts were prepared by sol-gel method with different molar ratios of total metal cations to citric acid ([Men+]T/CA) and employed as heterogeneous catalysts to activate peroxymonosulfate (PMS) for the removal of iohexol. The catalysts were characterized by various technologies, and the effect of [Men+]T/CA molar ratio on the catalysts' properties was explored. The CuFe2O4 synthesized with [Men+]T/CA molar ratio of 1:1 showed the best catalytic activity to PMS, and 95.0% of 1.0 mg/L iohexol was removed within 15 min by using 50 mg/L CuFe2O4 and 20 mg/L PMS. The quenching experiment and electron spin resonance (ESR) spectra indicated the generation of SO4- and OH in the CuFe2O4/PMS system, and the quantity experiments revealed that the generation concentration of SO4- was ten times higher than that of OH. The generation mechanism of SO4- and ·OH were investigated by ATR-FTIR and X-ray photoelectron spectroscopy (XPS) spectra. The effects of catalyst dosage, PMS and iohexol concentration on the removal of iohexol were studied, and various water matrix factors including solution pH, natural organic matter (NOM) concentration and inorganic ions were also considered. Based on the twelve intermediate products of iohexol detected by UPLC-QTOF/MS, the degradation pathway was proposed. The high catalytic activity and reusability of CuFe2O4 indicated that CuFe2O4 activating PMS is an effective and sustainable way for the treatment of iohexol.

Activation of peroxymonosulfate by palygorskite-mediated cobalt-copper-ferrite nanoparticles for bisphenol S degradation: Influencing factors, pathways and toxicity evaluation.

Peroxymonosulfate (PMS)-based advanced oxidation process is considered a potential technology for water treatment. Here, palygorskite (PAL)-mediated cobalt-copper-ferrite nanoparticles (16%-CoCu0.4Fe1·6O4@PAL, donated as 16%-CCFO@PAL) were employed for PMS activation to remove bisphenol S (BPS). BPS degradation was greater than 99% under the optimal conditions within 25 min, on which the effects of various influencing factors were explored. The adsorption dissociation energy of PMS over 16%-CCFO@PAL was -6.27 eV, which was lower than that of the Cu-free catalyst (-6.15 eV), demonstrating the excellent catalytic ability of 16%-CCFO@PAL. The efficient catalytic ability of 16%-CCFO@PAL was also verified in real water samples. The oxidation intermediates were identified and their generations were systematically analyzed by DFT calculations. The possible degradation pathways of BPS were proposed and the toxicity of products was predicted. BPS affected the normal development of zebrafish embryos and the levels of sex hormone in adult male zebrafish, and was harmful to the tissues, such as testis, liver, and intestine of zebrafish. The 16%-CCFO@PAL/PMS process can effectively reduce the toxicity of BPS-polluted water. This study paves the way for the real application of 16%-CCFO@PAL/PMS oxidation process and provides a new perspective for the evaluation of water toxicity.

Preparation of novel N-doped biochar and its high adsorption capacity for atrazine based on π-π electron donor-acceptor interaction.

Novel nitrogen (N)-doped cellulose biochar (NC1000-10) with large adsorption capacity (103.59 mg g-1) for atrazine (ATZ) was synthesized through the one-pot method. It has the best adsorption efficiency than N-doped biochars prepared from hemicellulose and lignin. The adsorption behaviors of ATZ by N-doped biochars with different N doping ratios (NC1000-5, NC1000-10, NC1000-20 and NC1000-30) were significantly different, which was attributed to the difference of sp2 conjugate C (ID/IG = 0.99-1.18) and doped heteroatom N (pyridinic N, pyrrolic N and graphitic N). Adsorption performance of ATZ on NC1000-10 conformed to the pseudo-second-order kinetic and Langmuir adsorption isotherm model. Thermodynamic calculations showed that adsorption performance was favorable. Besides, wide pH adaptability (pH = 2-10), good resistance to ionic strength and excellent recycling efficiency make it have extensive practical application potential. Further material characterizations and the density functional theory (DFT) calculations indicated that good adsorption performance of NC1000-10 for ATZ mainly depended on chemisorption, and π-π electron donor-acceptor (EDA) interaction contributed the most due to high graphitization degree. Specifically, pyridinic N and graphitic N further promoted adsorption performance by hydrophobic effect and π-π EDA interaction between ATZ and NC1000-10, respectively. Pyrrolic N and other surface functional groups (-COOH, -OH) facilitated the hydrogen bond effect.

LINC00261 Suppresses Cisplatin Resistance of Esophageal Squamous Cell Carcinoma Through miR-545-3p/MT1M Axis.

To improve the survival rate and cure rate of patients, it is necessary to find a new treatment scheme according to the molecular composition of (ESCC) in esophageal squamous cell carcinoma. Long non-coding RNAs (lncRNAs) regulate the progression of ESCC by various pathophysiological pathways. We explored the possible function of the lncRNA LINC00261 (LINC00261) on cisplatin (DDP) resistance of ESCC and its relative molecular mechanisms. In the study, we found that LINC00261 was downregulated in ESCC tissues, cell lines, and DDP-resistant ESCC patients. Besides, overexpression of LINC00261 not only inhibited cell proliferation, and DDP resistance but also promotes cell apoptosis. Further mechanistic research showed that LINC00261 sponged miR-545-3p which was negatively correlated with the expression of LINC00261. In addition, functional experiments revealed that upregulation of miR-766-5p promoted proliferation and enhanced DDP resistance. Subsequently, MT1M was testified to be the downstream target gene of miR-545-3p. Rescue experiments revealed that overexpression of MT1M largely restores miR-545-3p mimics-mediated function on ESCC progression. Our results demonstrate that the LINC00261 suppressed the DDP resistance of ESCC through miR-545-3p/MT1M axis.

Facile Fabrication of Three-Dimensional Fusiform-Like α-Fe2O3 for Enhanced Photocatalytic Performance.

α-Fe2O3 fusiform nanorods were prepared by a simple hydrothermal method employing the mixture of FeCl3·6H2O and urea as raw materials. The samples were examined by X-ray diffraction (XRD), high-resolution transmission electron microscopy (HRTEM), scanning electron microscopy (SEM), Fourier transform infrared (FTIR) spectroscopy and UV-vis diffuse reflectance spectra (UV-DRS). Its visible-light photocatalytic performances were evaluated by photocatalytic decolorization methylene blue (MB) in visible light irradiation. It was found that pure phase α-Fe2O3 nanorods with a length of about 125 nm and a diameter of 50 nm were successfully synthesized. The photocatalytic decolorization of MB results indicated that α-Fe2O3 nanorods showed higher photocatalytic activity than that of commercial Fe2O3 nanoparticles-these are attributed to its unique three-dimensional structure and lower electron-hole recombination rate.

A study of freeway crash risk prediction and interpretation based on risky driving behavior and traffic flow data.

The prediction of traffic crashes is an essential topic in traffic safety research. Most of the previous studies conducted experiments on real-time crash prediction of expressways or freeways, based on traffic flow data. However, the influence of risky driving behavior on traffic crash risk prediction has rarely been considered. Thus, a traffic crash risk prediction model based on risky driving behavior and traffic flow has been developed. The data employed in this research were captured using the in-vehicle AutoNavigator software. A random forest to select variables with strong impacts on crashes and the synthetic minority oversampling technique (SMOTE) to adjust the imbalanced dataset were included in the research. A logistic regression model was developed to predict the risk of traffic crash and to interpret its relationship with traffic flow and risky driving behavior characteristics. This model accurately predicted 84.48% of the crashes, while its false alarm rate remained as low as 9.75%, which indicated that this traffic crash risk prediction model had high accuracy. By analyzing the relationship between traffic flow, risky driving behavior, and crashes through partial dependency plots (PDPs), the impact of traffic flow and risky driving behavior variables on certain traffic crashes in the prediction model were determined. Through this study, the data of traffic flow and risky driving behavior could be used to assess the traffic crash risk on freeways and lay a foundation for traffic safety management.

Runge-Kutta Numerical Method Followed by Richardson's Extrapolation for Efficient Ion Rejection Reassessment of a Novel Defect-Free Synthesized Nanofiltration Membrane.

A defect-free, loose, and strong layer consisting of zirconium (Zr) nanoparticles (NPs) has been successfully established on a polyacrylonitrile (PAN) ultrafiltration substrate by an in-situ formation process. The resulting organic-inorganic nanofiltration (NF) membrane, NF-PANZr, has been accurately characterized not only with regard to its properties but also its structure by the atomic force microscopy, field emission scanning electron microscopy, and energy dispersive spectroscopy. A sophisticated computing model consisting of the Runge-Kutta method followed by Richardson extrapolation was applied in this investigation to solve the extended Nernst-Planck equations, which govern the solute particles' transport across the active layer of NF-PANZr. A smart, adaptive step-size routine is chosen for this simple and robust method, also known as RK4 (fourth-order Runge-Kutta). The NF-PANZr membrane was less performant toward monovalent ions, and its rejection rate for multivalent ions reached 99.3%. The water flux of the NF-PANZr membrane was as high as 58 L · m-2 · h-1. Richardson's extrapolation was then used to get a better approximation of Cl- and Mg2+ rejection, the relative errors were, respectively, 0.09% and 0.01% for Cl- and Mg2+. While waiting for the rise and expansion of machine learning in the prediction of rejection performance, we strongly recommend the development of better NF models and further validation of existing ones.

Selective adsorption and enhanced photodegradation of diclofenac in water by molecularly imprinted TiO2.

In the paper, molecularly imprinted TiO2 was prepared by surface molecularly imprinted technology and liquid phase deposition method for preferential removal of persistent toxic pollutants from complex environmental water. Diclofenac was selected as the template molecule and target for photodegradation study. The characterization results of SEM, TEM, FTIR and XRD showed that the TiO2 film with imprinted diclofenac was successfully synthesized on the surface of TiO2 particles. Meanwhile, the adsorption and photodegradation experiments also indicated that the molecularly imprinted TiO2 had larger adsorption capacity, better selectivity and higher photodegradation performance for diclofenac than non-imprinted TiO2. The primary active species and degradation pathways during photodegradation process were also elucidated according to radical capture experiments and UPLC-MS-TOF technology. The prepared molecularly imprinted TiO2 has the advantages of efficient removal ability, high stability and environmental protection, so it has a wide application value in water treatment and water environmental restoration, especially when involved persistent toxic pollutants.

Catalytic ozonation of iohexol with α-Fe0.9Mn0.1OOH in water: Efficiency, degradation mechanism and toxicity evaluation.

Iohexol, a widely used iodinated X-ray contrast media, is difficult to completely degrade with the traditional water treatment process. Catalytic ozonation with synthesized α-Fe0.9Mn0.1OOH as the catalyst can significantly promote the degradation of iohexol relative to that with ozonation alone. Hydroxyl radicals play a predominant role during the degradation of iohexol. The effect of various factors, including catalyst dose, ozone dose, iohexol concentration and water matrix factors, on the catalytic performance were investigated. The presence of α-Fe0.9Mn0.1OOH in the catalytic system can significantly promote the removal of iohexol and mineralization of the dissolved organic carbon in real water samples. The intermediate products were determined by high-resolution liquid chromatography, and the reaction site was predicted by frontier electron density (FED) calculations. The degradation mechanism of iohexol followed the processes of H-abstraction, amide hydrolysis, amide oxidation, and ·OH substitution. Higher exposure concentrations of iohexol had a negative effect on the survival and hatching rates in the development of zebrafish embryos. The autonomic movement process and heartbeat rate of the zebrafish larvae showed significant differences as the exposure concentration of iohexol increased. The catalytic ozonation process with α-Fe0.9Mn0.1OOH can decrease the toxicity of iohexol containing water.