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Advanced oxidation processes based on peroxymonosulfate (PMS) are effective methods for treatment of organic contaminants. Catalysts have a key role in these processes. In this study, we employed a novel penicillin residue-derived nitrogen-rich biochar to activate PMS for tetracycline (TC) degradation. Experimental results indicate that the removal rate reached its maximum (86.2%) within 20 min under the optimal conditions. In addition, after five cycles, the removal efficiency decreased only slightly. A combined analysis of the physical structure and chemical properties with chemical scavengers, electron paramagnetic resonance, and electrochemical tests confirmed that the catalyst had a dual role. Nitrogen doping and C O groups on the catalyst acted as active sites, which could produce superoxide radicals (O 2 •- ) and singlet oxygen (1O 2). The catalyst can also act as an electron transfer mediator to enhance the degradation process. Liquid chromatography–mass spectrometry (LCMS) was used to reveal the intermediates of TC degradation, potential degradation pathways are proposed, and the toxicity of the intermediates was analyzed. This research provides an effective strategy for the treatment of tetracycline and new approach to adequately remove antibiotic residues. [ABSTRACT FROM AUTHOR]

Avian leukosis virus (ALV) is associated with immune suppression, neoplasia, and reduced performance in chickens. In this study, two strains of ALV were isolated from Luxi gamecocks by DF-1 cell culture and identified by PCR, immunofluorescence assay, and sequencing of the viral genome. These strains were found to be novel recombinant viruses with nucleotide sequence identity of over 93.0% in the LTR and 94.4% in U3 to ALV-J, over 95.0% in the 5'UTR to ALV-C, over 93.4% in gp85 to ALV-B, and over 96.0% in gp37 to ALV-E. These results indicate that these two isolates are recombinants between ALV-J, ALV-C, ALV-E and ALV-B. [ABSTRACT FROM AUTHOR]

In order to study their synergistic catalytic effects in toluene degradation, CuMn 2 O 4 /HTS-1 (HTS-1 was a titanium silicon molecular sieve), Cu 0.7 Mn 2 Y 0.3 O x /HTS-1 and Cu 0.7 Mn 2 Ce 0.3 O x /HTS-1 catalysts were prepared by the impregnation method. The textural properties, redox properties and acidity of the catalysts were characterized by X-ray diffractometer (XRD), transmission electron microscopy (TEM), scanning electron microscopy (SEM), H 2 temperature-programmed reduction (H 2 -TPR), X-ray photoelectron spectroscopy (XPS), frustrated total internal reflection (FT-IR), ammonium temperature-programmed desorption (NH 3 -TPD) and pyridine adsorption internal reflection (Py-IR) measurements. The potential roles of Lewis acid sites (activating dioxygen) were discussed, and the experimental results indicated that the most efficient route for toluene degradation over Cu 0.7 Mn 2 Ce 0.3 O x /HTS-1 (toluene conversion rate of 90% (T 99) = 295°C) was ascribed to regulation of the synergistic effects of redox properties (activating molecular toluene) and Lewis acid sites (activating dioxygen). The Mars–Van–Krevelen (MVK) model was adopted to describe the reaction process of toluene oxidation, which gave an in-depth view into the toluene degradation over CuMn 2 O 4 /HTS-1, Cu 0.7 Mn 2 Y 0.3 O x /HTS-1 and Cu 0.7 Mn 2 Ce 0.3 O x /HTS-1. In addition, the synergistic effects between redox properties and Lewis acid sites were studied in detail. Unlabelled Image [ABSTRACT FROM AUTHOR]

To efficiently treat low-concentration chromium wastewater at low cost, adsorbent iron-modified ceramsite (FCM) was successfully prepared. The adsorbent was characterized by SEM, XRD, FT-IR, XPS, ζ potential and VSM. From the experimental results, the optimum adsorption pH, adsorbent dosage and adsorption time were 4, 1 g/L and 120 min, respectively. The percentage removal of Cr(VI) was 93% and the reduction efficiency of Cr(VI) was 74.3% when the concentration was 2 mg/L. After 5 cycles, using 0.1 mol/L NaOH as the regeneration agent, the removal rate of Cr(VI) did not decrease significantly. Furthermore, the mechanism of deep reduction and adsorption, the process of regeneration, the kinetics and adsorption isotherms were also explored. This paper can provide theoretical and technical support for reducing the toxicity and the advanced treatment of hexavalent chromium. Unlabelled Image • FCM can realize deep reduction and adsorption of Cr(VI) at low-cost. • The adsorption and regeneration mechanisms were studied in-depth. • The pseudo second-order kinetic model was found to correlate the experimental data well. • The adsorption isotherm conformed to Langmuir Model. [ABSTRACT FROM AUTHOR]

To achieve efficient degradation of toluene, a series of Cu 1-y Mn 2 Ce y O x /sepiolite catalysts ( y  = 0.1, 0.2, and 0.3) with different Cu 1-y Mn 2 Ce y O x loadings (10%, 20%, and 30%) were prepared via the co-precipitation method. The structure-activity and surficial elemental species of Cu 1-y Mn 2 Ce y O x /sepiolite were characterized by XRD, TEM, SEM, BET, ICP-MS and XPS. The catalytic activity of the catalysts was tested in the oxidation reaction of toluene, results showed that 20%Cu 0.8 Mn 2 Ce 0.2 O x /sepiolite remains able to remove toluene completely with high efficiency at a temperature of 289 °C. Two kinetic models have been selected and tested to describe the oxidation of toluene, the Mars-van krevele (MVK) model provided a good fit (R 2  ≥ 0.99). And the optimal relation of the surface oxidation activation energy (26.074 kJ mol −1 ) and surface reduction activation energy (23.591 kJ mol −1 ) were calculated. [ABSTRACT FROM AUTHOR]

We report on the synthesis, characterization and catalytic performance of a palladium-based superparamagnetic catalyst of Fe3O4@polyaniline core/shell microspheres (Fe3O4@PANI–PdII). The material was characterized by TEM, FT-IR, vibrating sample magnetometry (VSM), XRD, and XPS. The catalyst showed high activity for the carbonylative cross-coupling reaction of aryl iodide with arylboronic acid. Moreover it could selectively reduce the formation of a direct-coupling product. The newly developed catalyst could be recovered from the liquid phase easily by magnetic separation and recycled 5 times without any significant loss of activity. [ABSTRACT FROM AUTHOR]

A hollow magnetic mesoporous silica sphere (HMMS) catalyst has been synthesized using polystyrene microspheres as a chemical template. The catalyst was characterized by TEM, XRD, XPS and vibrating sample magnetometry (VSM). The catalyst shows high activity for the carbonylative cross-coupling reaction of aryl iodides with arylboronic acids and Suzuki coupling reactions. The newly developed catalyst is easy to recover by magnetic separation from the liquid phase of the reaction and can be recycled. Importantly, the catalyst revealed high efficiency and high stability under the reaction conditions and during recycling stages. [ABSTRACT FROM AUTHOR]

Abstract: A novel and high-performance palladium-based catalyst for Heck reaction was prepared easily by the co-precipitation method. The catalyst was characterized by transmission electron microscopy (TEM), X-ray powder diffraction (XRD), vibrating sample magnetometry (VSM), X-ray photoelectron spectroscopy (XPS) and atomic absorption spectrophotometry (AAS). The catalyst afforded a fast conversion of the 4-bromonitrobenzene to 4-nitrostilbene at a catalyst loading of 5mol%, and the efficiency of the catalyst remains unaltered even after 6 repeated cycles. The excellent catalytic performance of the Pd/Fe3O4 catalyst might be attributed to the enhanced synergistic effect between Pd nanoparticles and magnetite. [Copyright &y& Elsevier]

Spinel oxides, e.g., NiCo 2 O 4 , is a promising catalyst for the catalytic oxidation of toluene. Understanding and designing versatile NiCo 2 O 4 spinel is important for low-temperature toluene oxidation. Here, we investigated the surface-characteristic-dependent degradation activity of NiCo 2 O 4 crystals through experiment and characterization. NiCo 2 O 4 nanosheet using ethanol as solvent (named E--NiCo 2 O 4) exposing {110} crystal planes exhibited the lowest temperature toluene oxidation. The T 99 of toluene conversion was 256 °C, which is much lower than that of NiCo 2 O 4 nanosheet using ethylene glycol as solvent (named EG--NiCo 2 O 4), NiCo 2 O 4 octahedron (named O--NiCo 2 O 4) and NiCo 2 O 4 truncated octahedron (named TO--NiCo 2 O 4). Characterization using various techniques such as XRD, TEM, BET, XPS, H 2 -TPR and CO 2 -TPD showed that Co3+ and surface adsorbed oxygen (O sur) enriched surface, excellent redox properties and effective diffusion of the reaction product reasonably explain the enhancement in catalytic activity over the E--NiCo 2 O 4. The research reveals that the effect of specific crystal planes and solvent was the key factor to govern the activity of low-temperature toluene oxidation. Image 1 • The crystal planes can adjust the surface chemical properties of NiCo 2 O 4. • Solvent will affect the amount of high valence metal. • The O sur was the active component. • The amount and redox properties of Co3+ will affect continuously supply of O sur. • The catalyst showed good stability even when water was introduced the reaction. [ABSTRACT FROM AUTHOR]

A phosphorus removal biochar adsorbent was prepared from Fenton sludge. The adsorption process was optimized, and its phosphorus adsorption mechanism was discussed. It was found that the phosphorus adsorption performance of biochar prepared from single Fenton sludge (FBC‐400) was better than that of co‐pyrolysis of Fenton sludge and bamboo powder. The optimum condition was that Fenton sludge pyrolyzed at 400°C (FBC‐400). FBC‐400 had a larger specific surface area than that prepared by co‐pyrolysis with bamboo powder. And the high content of iron element could provide a higher surface charge of the biochar, thereby increasing the electrostatic adsorption of phosphorus onto FBC‐400. The phosphorus adsorption was highly pH dependent by FBC‐400, which can enhance electrostatic adsorption and increase adsorption capacity in acidic conditions. The effect of coexisting anion on adsorption performance was mainly affected by CO32−, reducing the adsorption capacity by at least 49%, whereas other anions had no obvious interference. The adsorption process of FBC‐400 accorded with the pseudo‐second‐order kinetic model and the Langmuir model, which indicated that the adsorption process was monolayer adsorption and mainly chemical adsorption, and the maximum saturated phosphorus adsorption capacity was 8.77 mg g−1. The mechanisms for phosphorus adsorption were electrostatic adsorption and inner‐sphere complexing. 1 M NaOH was used for desorption, and the adsorption capacity remained at 81% in the fifth cycle. Practitioner Points: The Fenton sludge biochar usage as an adsorbent could be a win‐win strategy to convert waste biomass to valuable ‐ product.The adsorption process accorded with the Langmuir model, the maximum phosphorus adsorption capacity was 8.77 mg/g at 25°C.The adsorption mechanisms were electrostatic adsorption and inner‐sphere complexing.1M NaOH was used for desorption, and the adsorption capacity remained at 81% in the fifth cycle. [ABSTRACT FROM AUTHOR]

Three core–shell structures were prepared with pyrrole, glucose, and tetraethyl orthosilicate (TEOS), respectively, encasing magnetic Fe3O4 microparticles, through three different “green” approaches without any toxic solvents. Pt nanoparticles (NPs) were immobilized onto these supports with NaBH4 as the reducing agent. The as-prepared catalysts were characterized thoroughly by TEM, VSM, XRD, FT-IR, ICP, and XPS. As expected, the shells remarkably affected the distribution of Pt NPs and catalytic activity. Pt NPs dispersed evenly on the surface of Fe3O4@PPy and Fe3O4@C, which were much better than Fe3O4@SiO2. Most attractively, the prepared catalysts exhibited better kinetics, higher activity and stability than Pt/Fe3O4 and Pt/C for selective oxidation of ethanol to acetic acid and glycerol to glyceric acid with molecular oxygen in water. Among them, the catalyst with a shell of polypyrrole (PPy) showed the best catalytic property, affording yields of 88% and 55%, respectively. Moreover, it could be recovered facilely from the reaction mixture and recycled four times without any significant loss in activity. [ABSTRACT FROM AUTHOR]

Solvent-dispersible magnetite nanoparticles (Fe3O4) end-functionalized with amino groups were successfully prepared by a facile one-pot template-free method to immobilize PdII and Pd0 using a metal adsorption and reduction procedure. They were characterized by TEM, XRD, XPS, FT-IR and VSM. Interestingly, the PdII catalyst exhibited better catalytic activity for carbonylative cross-coupling reactions than the Pd0 catalyst. According to the catalytic activities of a variety of arylboronic acids and aryl iodides catalyzed by two kinds of Pd catalysts, the proposed reaction mechanism of Suzuki carbonylative cross-coupling reactions using the Pd catalyst was also inferred. More importantly, agglomeration of Pd0 nanoparticles was obviously observed in the TEM images of the catalysts after reactions. Therefore, agglomeration of Pd0 nanoparticles should be considered as a significant reason for different catalytic activities of the reactions catalyzed by immobilized PdII and Pd0 catalysts. Furthermore, the PdII catalyst revealed high efficiency and stability during recycling stages. [ABSTRACT FROM AUTHOR]

Fe3O4@PPy composite microspheres have been synthesized using Fe3O4 microspheres as a chemical template in an ultrasonic treatment process. Pt nanoparticles (NPs) were immobilized on Fe3O4@PPy by using ethylene glycol (EG) and NaBH4 as reducing agents. The information on the morphologies, sizes, and dispersion of Pt NPs of the as-prepared catalysts was verified by TEM, XRD, FTIR and XPS. As expected, the chemical reduction methods remarkably affected the size of Pt NPs (∼2.5 nm and ∼5.5 nm) and the prepared catalysts exhibited high catalytic activities as well as awesome stabilities for aerobic oxidation of benzylic alcohols and hydrogenation reduction of nitroaromatics. It was highlighted that size effects for the catalytic properties of the two reactions were found to be quite different. Fe3O4@PPy–Pt (2.5 nm) afforded a higher conversion for benzylic alcohol aerobic oxidation, while the selectivities toward benzaldehyde over these two catalysts were similar. However, they showed almost the same catalytic performance for hydrogenation reduction of a majority of nitroaromatics. What is more, Fe3O4@PPy–Pt (5.5 nm) gave better activities than several nitroaromatics, which were relatively difficult to be hydrotreated under the same conditions. In addition, the EG reduced Fe3O4@PPy–Pt catalyst exhibited slightly poorer stability than the NaBH4 reduced Fe3O4@PPy–Pt catalyst in the recycle tests, which might be due to the agglomeration of small Pt NPs. [ABSTRACT FROM AUTHOR]

The unique hollow nanotube structure of 30% Co-CHNTs can efficiently degrade sulfamethoxazole antibiotics. [Display omitted] • The catalyst is synthesized by the impregnation-chemical reduction-calcination method. • The degradation rate of the catalyst to sulfamethoxazole within 30 min is 97.5%. • After the catalyst is calcined, the leaching of cobalt metal ions is reduced. • The catalyst still has a good degradation rate for sulfamethoxazole in natural water. • Non-radical singlet oxygen is the main active substance in the system. In this study, a new hollow nanotube material, 30% Co–CHNTs was prepared by the impregnation–chemical reduction–calcination method. This material can be used as a peroxymonosulfate (PMS) activator to catalyse the degradation of sulfamethoxazole (SMX). The best reaction conditions that correspond to the degradation rate of SMX, up to 97.5%, are as follows: the concentration of SMX is 10 mg L−1, the amount of catalyst is 0.20 g L−1, the dosage is 1.625 mM, and the solution pH is 6.00. X-ray photoelectron spectroscopy (XPS) and inductively coupled plasma optical emission spectrometry (ICP-OES) show that the calcined composites mainly stimulate an increase in the content of bivalent cobalt in PMS and reduce the leaching of cobalt ions after the reaction. Additionally, the 30% Co–CHNTs + PMS reaction system exhibits a reasonable SMX degradation rate in a natural organic matter solution and excellent stability after three repeated experiments. Furthermore, the possible degradation mechanism in the 30% Co–CHNTs + PMS reaction system was analysed through electron paramagnetic resonance (EPR) and free-radical capture experiments, and it was observed that the non-radical degradation of 1O 2 plays a leading role in SMX degradation. Finally, according to the nine degradation intermediates detected by liquid chromatography-mass spectrometry (LC–MS), four possible SMX degradation routes were proposed. This study proved that a 30% Co–CHNTs heterogeneous catalyst is easily prepared, inexpensive, and environmentally friendly and has potential application in antibiotic wastewater treatment. [ABSTRACT FROM AUTHOR]

Flow electrode capacitive deionization (FCDI), a novel ion removal technology, is influenced by various factors such as electrode material properties, fluid flow rate, and device structure. In the FCDI system, the intermediate chamber is the core element where ions migrate towards the cathode and anode to complete the adsorption process. In this study, we designed a hollow plastic plate with channels (PP) and a hollow graphite plate with channels (GP) as the intermediate chamber, compare and study with conventional plastic mesh (PM) chambers. CFD simulations revealed that the newly designed PP and GP chambers significantly reduced the hydraulic stagnation zone. The results of the desalination experiments revealed that the desalination efficiency of the GP-FCDI was 1.5 and 1.9 times higher than that of the PP-FCDI and PM-FCDI, respectively. At the same time, in situ potential measurement (ISPM) was used to monitor the voltage drop of each component in FCDI, thereby accurately calculated the proportion of energy consumption in the intermediate chamber. The results indicate that the energy consumption of the intermediate chamber of GP-FCDI was 54 % less than that of PM-FCDI. The current work will help us provide new insights for the design and optimization of FCDI systems. • Replaced conventional FCDI intermediate chamber with flow channel • Innovative introduction of graphite plate into the intermediate chamber • The effects of hydraulic distribution on desalination performance were analyzed. • The SEC of each component of the FCDI device was calculated separately. [ABSTRACT FROM AUTHOR]

Flow electrode capacitive deionization (FCDI) is a new ion removal technology with sustainable deionization performance. However, the interface resistance has a significant impact on ions migration in FCDI. We therefore introduced a novel FCDI device that incorporated a layer of carbon felt as an "ionic capacitor" between the flow electrode and the ion exchange membrane, termed CF-FCDI. Mechanism exploration results revealed that the addition of carbon felt reduced device resistance, shorten electron transfer pathways, improved charge efficiency, and increased ion migration rate. Experimental results demonstrated that the improved CF-FCDI device achieved 44 % higher desalination rate compared to traditional device. In addition, long term operation experiments confirmed the stability of CF-FCDI device, highlighting its potential as a viable desalination solution. The findings of this study provided valuable insights for further development of FCDI and offered a promising solution for its applications such as seawater desalination. [ABSTRACT FROM AUTHOR]

• A genetically stable mutant strain KT16 was screened by UV-DES compound mutagenesis. • The enzyme activity of KT16 increased by 46.7% compared to the original strain DC8. • Mutagenesis enhanced the ability of S-TE, facilitated the recovery of protein in ES. • Whole genome resequencing analysis of KT16 was performed to detect the mutant sites. Excess sludge (ES), a resource-rich organic waste, can be solubilized by thermophilic enzymes to extract proteins for sludge reduction and resources recovery. To solve the problems of low hydrolysis effect of ES and low enzyme producing ability of wild thermophilic bacteria, ultraviolet and diethyl sulfate (UV-DES) were adopted to mutate thermophilic bacteria in this study. Mutation sites were detected and annotated by whole genome sequencing analysis. The results showed that UV-DES mutagenesis could effectively improve enzyme-producing capacity of thermophilic bacteria and promote the hydrolysis of ES. The protease activity of the mutant strain KT16 was 46.7 % higher than that of the original strain DC8. The protein extraction rate with enzyme produced by KT16 reached 83.3 %. The total content of proteins recycled through KT16 enzyme solution was 3539.6 mg·L-1, 18.4 % higher than that of DC8. This work provided a theoretical idea and technical guidance for the protein recovery from ES. [ABSTRACT FROM AUTHOR]

Genome-wide functional genetic studies of food-borne pathogens could provide a comprehensive understanding of the mechanisms underline their survival and pathogenesis in the harsh environments during food processing and infections. Traditional methods such as physical mutagenesis, chemical mutagenesis, and labeled DNA fragment insertion mutation techniques are time-consuming, labor-intensive and low precision. Although RNA-Seq and other omics methods enable high-throughput research on a genome-wide scale, the obtained results of gene transcription or expression cannot establish direct causal connection between the genetic determinants and particular functions. Transposon sequencing (Tn-seq) is an emerging microbial functional genomic technology based on transposon mutagenesis and high-throughput sequencing technologies, which is able to quantitatively track millions of independent mutants in a single experiment, and therefore efficiently map the "genotype-phenotype" relationship and the genetic interaction networks of a bacterium. This article summarizes the common types and hazards of food-borne pathogens, the development of Tn-seq technology, and its applications in studying the physiology, pathogenesis, and environmental survival of food-borne pathogens. • Food-borne pathogens are a common concern of food safety worldwide. • Transposon sequencing (Tn-seq) is an emerging microbial functional genomics technology. • Tn-seq can efficiently establish "genotype-phenotype" correspondence. • The development and applications of Tn-seq are reviewed. [ABSTRACT FROM AUTHOR]

Highlights: [•] The acid–base bifunctional magnetic nanoparticles have been successfully prepared. [•] The nanoparticles possess excellent magnetism, narrow diameter distributions and crystallinity. [•] The novel magnetic nanoparticles show enhanced catalytic activity. [•] A cooperative catalysis may exist between the general acid and base sites to improve the catalytic activity. [Copyright &y& Elsevier]

[Display omitted] • The series connection method of flow electrode ST-SC and MT-SC in multi-stage FCDI were proposed. • Flexible current control each level device to decrease ENRS. • MT-SC operating mode was more energy-efficient and efficient than traditional single stage devices. • The MT-SC operating mode could fully utilize the energy released during the desorption process. This article proposed a three-stage flow electrode capacitive deionization (FCDI) device, in which the flow electrodes were connected in series and circulated among the three stages. Four different methods of flow electrode series connection (ICC, SCC, ST-SC, and MT-SC) were investigated. The results showed that the MT-SC mode achieved the best desalination performance and saved 43.47 % of energy. To further reduce energy consumption, the current of the three-stage device was further optimized using flexible current, and the mode with gradually decreasing current (15 mA-10 mA-5 mA) was the most effective. Moreover, the effects of flow rate, influent salt concentration and current on the desalination performance of the three-stage FCDI device were studied. A fair comparison was made between the desalination performance of three-stage and single-stage FCDI devices, and the results showed that the multi-stage FCDI device with series flow electrodes can fully utilize the energy released during the short-circuit desorption process to reduce the energy consumption of desalination. Therefore, the multi-stage FCDI devices were more energy-efficient and economical than traditional single-stage devices. [ABSTRACT FROM AUTHOR]

[Display omitted] • A novel E H 2 O 2 -MB-O 3 process was developed for antibiotics removal from wastewater. • More efficient CIP removal and mineralization were achieved in E H 2 O 2 -MB-O 3 process. • •OH oxidation was enhanced in E H 2 O 2 -MB-O 3 and contributed to CIP removal mainly. • Pyridone and piperazine ring in CIP molecule could be attacked by •OH more easily. Microbubble ozonation combined with electro-generated H 2 O 2 process (E H 2 O 2 -MB-O 3) was applied to degrade ciprofloxacin (CIP) as a typical antibiotic in wastewater in this study. The results showed that the performance of CIP degradation and mineralization in E H 2 O 2 -MB-O 3 process was more efficient than other related processes. Microbubble ozonation and electro-generated H 2 O 2 showed obvious synergistic effect on enhanced CIP removal in E H 2 O 2 -MB-O 3 process. The O 3 dosage, applied current and initial pH in E H 2 O 2 -MB-O 3 process were optimized as 12.5 mg/min, 50 mA and 7.0 (uncontrolled). Under the optimal conditions, CIP could be degraded completely within 60 min and the TOC removal efficiency of 28.85% could be achieved within 90 min in E H 2 O 2 -MB-O 3 process. The corresponding ozone utilization efficiency was close to 100%. More efficient ROS generation was observed in E H 2 O 2 -MB-O 3 process, especially •OH, compared with other related processes. The contribution rates of •OH, 1O 2 , O 3 and O 2.- to CIP removal were determined as 66.79%, 23.57%, 6.67% and 2.98% in E H 2 O 2 -MB-O 3 process, respectively. The electro-generated H 2 O 2 was clarified to contribute to not CIP removal but ROS generation. Three CIP degradation pathways were proposed according to identified degradation intermediates, which indicated that pyridone structure of quinoline and piperazine ring in CIP molecule could be destroyed more easily than benzene ring of quinoline, and the hydroxylation seemed to prevail in these CIP degradation pathways due to •OH electrophilic addition reaction probably. The removal of other antibiotics in E H 2 O 2 -MB-O 3 process also depended on not ozone direct oxidation but •OH oxidation mainly. [ABSTRACT FROM AUTHOR]

Abstract The Brucella spp encounter stressful environment inside their host cells. The Lon protein is an important protease related to cellular protein degradation and resistance to stress in Brucella. However, the molecular mechanism between Lon protein and stress response was still unknown. In this study, it was found that the lon mutant exhibited obvious growth defect in TSB medium, compared with its parent strain. In addition, our results indicated that Lon protein was involved in resistance to various stress conditions and all the β-lactam antibiotics tested. Although deletion of this protease did not affect Brucella virulence in macrophage, the mutant strain was significantly attenuated in mice infection model at 1 week post infection, and the expression level of several cytokine genes was significantly changed in vivo. To gain insight into the genetic basis for the distinctive phenotypic properties exhibited by the lon mutant strain, RNA-seq was performed, and the result showed that various genes involved in stress response, quorum sensing and transcriptional regulation were significantly altered in Δ lon strain. Overall, these studies have preliminary uncovered the molecular mechanism between Lon protease, stress response and bacterial virulence. Highlights • The lon mutant exhibited obvious growth defect in TSB medium. • Lon protein was involved in resistance to various stress conditions and all the β-lactam antibiotics tested. • Genes involved in stress response, quorum sensing and transcriptional regulation were significantly altered in Δ lon strain. [ABSTRACT FROM AUTHOR]

[Display omitted] • Provides a new idea for the recycle and harmless treatment of AMD. • More than 99% terramycin was reduced after adding HCMI of compost. • By adding HCMI, Qac B and tet H decreased by 0.35, and 0.15%, respectively. • The succession of microorganism had greatly factor on the varies of ARG subtypes. • The HCMI improve the removal rate of ARG subtype to a certain extent. In order to tackle the issue of terramycin mycelial dreg (TMD) diagnosis and removal of terramycin and antibiotic resistance genes (ARGs), this study adopted aerobic composting (AC) technology and added homemade compound microbial inoculum (HCMI) to promote the AC of TMD and enhance the removal of terramycin and ARGs. The findings demonstrated that terramycin residue could be basically harmless after AC. Moreover, HCMI not only reduced Qac B and tet H but also increased the degradation rates of Van RA, Van T, and dfr A24 by 40.81%, 5.65%, and 54.18%, respectively. The HCMI improved the removal rate of ARG subtypes to a certain extent. According to redundancy analysis, during AC, the succession of the microbial community had a stronger influence on the variance of ARG subtype than the environmental conditions. Differences in the abundance of various bacteria due to changes in temperature may be an intrinsic mechanism for the variation of ARG subtypes. [ABSTRACT FROM AUTHOR]

• Biochar improved the efficiency of anaerobic digestion of antibiotic residues. • BC and nZVI-BC increased the gas production efficiency by 20.75% and 15.50%, respectively. • The effect of nZVI-BC was greater than BC in reducing ammonia nitrogen content. • nZVI-BC significantly enhanced the removal of aad A, ant (2″)-Ⅰ, qacEdelta 1 and sul 1. To address the problem of antibiotic mycelial dreg (AMD) treatment and removal of antibiotic resistance genes (ARGs), this study adopted anaerobic digestion (AD) technology, and added biochar (BC) and biochar loaded with nanosized zero-valent iron (nZVI-BC) to promote the AD of AMD and enhance the removal of ARGs. Results showed that nZVI-BC was better than BC in promoting AD due to the hydrogen evolution corrosion and the synergistic effect of nZVI and BC. In addition, BC and nZVI-BC can enhance the oxidative stress response and reduce ammonia stress phenomenon, which significantly reduces the abundance of aad A, ant(2″) -Ⅰ, qacEdelta 1 and sul 1. In conclusion, the enhance effect of nZVI-BC is greater than BC. The removal efficiency rates of nZVI-BC on the above-mentioned four ARGs were improved by 33%, 9%, 24% and 11%. [ABSTRACT FROM AUTHOR]

Flow electrode capacitive deionization (FCDI) has great advantages in high salinity wastewater desalination. However, due to the limited adsorption capacity of electrode material, membrane concentration polarization would form and increase energy consumption, and affect the continuity of desalination. In this work, milling technology was used to modify original activated carbon (AC), the obtained ball milled activated carbon (BAC) was used as FCDI electrode material. The milling process modified multiple physical and electrochemical characteristics of original AC. The highest average salt removal rate (ASRR) of BAC was 2.2 times of that of AC, which was attributed to the modified surface properties including more oxygenated functional group, larger electrostatic gravitation characteristics and better hydrophilicity. The reduced concentration polarization during the desalination was responsible for the increased adsorption capacity, which was due to larger electrolyte contact area, enhanced ions capacity by more suitable pore structures, and 5 times higher energy normalized removal salt (ENRS) of BAC flow electrode than that of AC. Because of its simple operation and remarkable modification effect, ball milling technology shows great potential in large scale modification of electrode materials. [ABSTRACT FROM AUTHOR]

Considering the complexity of traditional cobalt phosphide (Co 2 P) loaded biochar synthesis research on a simple and efficient synthesis method has practical significance. In this study, after phosphoric acid activation, Neosinocalamus affinis biochar (NAB) and nanoplate Co 3 O 4 quickly formed a Co 2 P-NAB composite material with high Co 2 P crystallinity and was uniformly dispersed on the surface of NAB in a microwave reactor. Co 2 P-NAB has an excellent catalytic degradation effect in the activation of peroxymonosulfate (PMS) to degrade tetracycline (TC). The optimal TC degradation efficiency was achieved with the addition of 50 mg L−1 TC concentration, 0.2 g L−1 catalysts, 0.406 mM PMS and pH = 6.02. In addition, according to the pseudo-first-order reaction rate constant calculation, the composite of Co 2 P-NAB and PMS the synergy efficiency is 81.55 %. Compared with Co 2 P-NAB (10.83 %) and PMS (7.62 %) alone, the Co 2 P-NAB/PMS system has a significant promotion effect on the degradation of TC molecules. Additionally, the Co 2 P-NAB/PMS system had a TC mineralization rate of 68 % in 30 min. Furthermore, after a series of characterization, detection and analysis, and influencing factor experiments, we proposed a potential mechanism for the Co 2 P–NAB/PMS reaction system to degrade TC and found that singlet oxygen (1O 2) plays an essential role in the non-radical degradation process. Finally, according to the liquid chromatography-mass spectrometry (LC-MS) detection of TC degradation intermediates, a possible degradation route was proposed. Therefore, this work uses microwave technology to present a novel and simple synthesis method for transition metal phosphides, which provides potential application value for the treatment of actual wastewater with heterogeneous catalysts. Co 2 P functionalized neosinocalamus affinis biochar for pH-universal degradation of antibiotic tetracycline. [Display omitted] • Microwave assisted synthesis for preparing Co 2 P decorated biochar material. • The unique porous Co 2 P-NAB material can efficiently degrade tetracycline in water. • Co 2 P-NAB/PMS degrades antibiotic tetracycline in a broad pH ranging from 3 to 11. • Non-radical singlet oxygen acts as the main active sites in Co 2 P-NAB/PMS system. [ABSTRACT FROM AUTHOR]

Herein, a non-stacked γ-Fe2O3/C@TiO2 double-layer hollow nano photocatalyst has been developed with ultrathin nanosheets-assembled double shells for photodegradation phenol. High catalytic performance was found that the phenol could be completely degraded in 135 min under visible light, due to the moderate band edge position (VB at 0.59 eV and CB at −0.66 eV) of the non-stacked γ-Fe2O3/C@TiO2, which can expand the excitation wavelength range into the visible light region and produce a high concentration of free radicals (such as ·OH, ·O2−, holes). Furthermore, the interior of the hollow composite γ-Fe2O3 is responsible for charge generation, and the carbon matrix facilitates charge transfer to the external TiO2 shell. This overlap improved the selection/utilization efficiency, while the unique non-stacked double-layered structure inhibited initial charge recombination over the photocatalysts. This work provides new approaches for photocatalytic applications with γ-Fe2O3/C-based materials. [ABSTRACT FROM AUTHOR]

Abstract: A simple and novel method to fill carbon nanotubes (CNTs) with Ni–Fe alloys by methylbenzene-oriented constant current electrodeposition is demonstrated. The method is based on the difference in the surface conductivity of CNTs inside and outside in electrodeposition process owing to the covering of methylbenzene. The Ni–Fe alloys filled multiwalled carbon nanotubes (MWCNTs) were characterized by transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), vibrating sample magnetometer (VSM) and atomic absorption spectroscopy (AAS), respectively. Then the Ni–Fe alloys filled MWCNTs were used as hydrazine oxidation electrocatalysts in direct hydrazine (N2H4)-air fuel cells. Cyclic voltammograms (CVs) indicated that Ni85Fe15-filled MWCNTs had superior electrocatalytic activity for hydrazine electrocatalysis than catalysts with other compositions. [Copyright &y& Elsevier]

A palladium-based catalyst supported on amine-functionalized magnetite nanoparticles was successfully prepared by a facile one-pot template-free method combined with a metal adsorption–reduction procedure. The catalyst was characterized by TEM, XRD, XPS, FT-IR and VSM. The catalyst afforded fast conversions for various aromatic nitro and unsaturated compounds, and with a turn-over frequency (TOF) of 83.33 h−1under a H2atmosphere in ethanol, even at room temperature. Furthermore, it was found that the catalyst showed a high activity for the Heck reaction, affording over a 93% yield in all the cases investigated. Interestingly, the novel catalyst could be recovered in a facile manner from the reaction mixture and recycled eight times without any significant loss in activity. [ABSTRACT FROM AUTHOR]

A palladium-based catalyst supported on amine-functionalized magnetite nanoparticles was successfully prepared by a facile one-pot template-free method combined with a metal adsorption–reduction procedure. The catalyst was characterized by TEM, XRD, XPS, FT-IR and VSM. The catalyst afforded fast conversions for various aromatic nitro and unsaturated compounds, and with a turn-over frequency (TOF) of 83.33 h−1 under a H2 atmosphere in ethanol, even at room temperature. Furthermore, it was found that the catalyst showed a high activity for the Heck reaction, affording over a 93% yield in all the cases investigated. Interestingly, the novel catalyst could be recovered in a facile manner from the reaction mixture and recycled eight times without any significant loss in activity. [ABSTRACT FROM AUTHOR]

Mannosylerythritol lipids-A (MEL-A) is a novel biosurfactant with excellent surface activity and potential biomedical applications. In this study, we explored the antibacterial activity and the underlying mechanisms of MEL-A against the important food-borne pathogen Listeria monocytogenes. The bacterial growth and survival assays revealed a remarkable antibacterial activity of MEL-A. Since MEL-A is a biosurfactant, we examined the cell membrane integrity and morphological changes of MEL-A-treated bacteria by biochemical assays and flow cytometry analysis and electron microscopes. The results showed obvious damaging effects of MEL-A on the cell membrane and morphology. To further explore the antibacterial mechanism of MEL-A, a transcriptome analysis was performed, which identified 528 differentially expressed genes (DEGs). Gene ontology (GO) analysis revealed that the gene categories of membrane, localization and transport were enriched among the DEGs, and the analysis of the Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways demonstrated significant changes in the maltodextrin ABC transporter system and stress response system. Furthermore, the growth of L. monocytogenes could also be significantly inhibited by MEL-A in milk, a model of a real food system, suggesting that MEL-A could be potentially applied as an natural antimicrobial agent to control food-borne pathogens in the food industry. [ABSTRACT FROM AUTHOR]

• A series of honeycombed catalysts were successfully constructed via facile in situ synthetic method. • Au@C-TiO 2-X exhibited superior catalytic activity for the deep mineralization of AR3R under visible light. • The introduction of C and Au species promote the generation of reactive oxygen species. • The superior photocatalytic activity of Au@C-TiO 2-X is attributed to the synergistic effect of •O 2 − and •OH. The mineralization of organic pollutants under visible light is challenging, limiting the practical application of photocatalytic technology in wastewater treatment. To achieve the efficient mineralization of Acid red 3R (AR3R), a series of honeycombed catalysts (TiO 2 , C-TiO 2-X , Au@TiO 2 and Au@C-TiO 2-X) were prepared via a facile in situ synthetic method and characterized by XRD, TEM, BET, XPS and DRS, respectively. The introduction of C and Au species promote the simultaneous generation of •O 2 − and •OH over Au@C-TiO 2-X under visible light radiation. The Au@C-TiO 2-X catalyst showed superior performance for the deep mineralization of AR3R, affording a TOC removal rate larger than 90 % within 240 min under visible light (> 420 nm). The photocatalytic degradation mechanism of AR3R is proposed according to UV–vis and in situ DRIFTS analysis. The superior photocatalytic activity of Au@C-TiO 2-X is attributed to the synergistic effect of •O 2 − and •OH owing to C doping and Au deposition. [ABSTRACT FROM AUTHOR]