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1.
J Hazard Mater ; 476: 135142, 2024 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-39029185

RESUMO

The occurrence of pyrrolizidine alkaloids (PAs) in the aquatic environment has received growing attention due to their persistent mutagenicity and carcinogenicity. In this study, the photooxidation processes of four representative PAs (senecionine, senecionine N-oxide, europine, and heliotrine) in the presence of dissolved organic matter (DOM) were investigated. The excited triplet DOM (3DOM*) was demonstrated to play a dominant role in the phototransformation of PAs. The observed degradation rates of PAs largely depended on the DOM concentration. Alkaline conditions and the presence of HCO3-/CO32- were conducive to the photodegradation. Based on kinetic modeling, the second-order reaction rate constants of PAs with 3DOM* were predicted to be (1.7∼5.3)×108 M-1 s-1, nearly two orders of magnitude higher than those with singlet oxygen (1O2). The monoester structure and electron-withdrawing substituent (e.g., -O atom) substantially affected the one-electron oxidation potential of PAs, which dictates the reaction rates of PAs with 3DOM*. Finally, a tentative degradation pathway of PAs was proposed, involving the formation of an N-centered radical cation through one-electron transfer, which then likely deprotonated and further oxidized to more persistent and toxic phototransformation products with an added oxygen atom into the pyrrole ring.

2.
J Hazard Mater ; 476: 135185, 2024 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-39013320

RESUMO

Membrane fouling generated by small molecular-weight aromatic compounds with poor biodegradability is a major barrier to advanced petrochemical wastewater treatment using nanofiltration (NF) technology. In this study, the fouling behavior of ten BTEX with different substituent existing in petrochemical wastewater on the NF membrane was systematically investigated. By examining the effect of the number, position, and type of substituents on the permeability of NF membranes and membrane resistance analysis, combined with XDLVO theory and correlation analysis, we found that stronger dipole-dipole interactions of BTEX with higher polarity and hydrogen bonding effects between substituents and the membrane surface were verified to be the main forces driving the attachment to the surface of membranes. Furthermore, by analyzing the effect of common inorganic ions in petrochemical wastewater on membrane fouling, it was found that electron-donating substituents (-CH3, -C2H5, and -NH2) enhanced the electron cloud density of the benzene ring, a process that exacerbated membrane fouling by strengthening electrostatic interactions between the benzene ring and Ca2+ ions. The fouling potential of electron-withdrawing substituted (-NO2, -OH) BTEX exhibited the opposite trend. Overall, this study provides a theoretical basis for developing effective membrane fouling control strategies in NF advanced treatment of petrochemical wastewater. ENVIRONMENTAL IMPLICATION: Aromatic chemicals in petrochemical effluent are difficult to degrade, and their accumulation will cause significant harm to humans and ecological systems. Determine the composition of small molecule BTEX in petrochemical wastewater, gain an in-depth comprehension of the membrane fouling behavior of nanofiltration membrane filtration, identify the primary forces causing irreversible membrane surface fouling using experimental data and model fitting, and propose viable anti-fouling membrane modification strategies. Establish a technical foundation for membrane fouling management in the long-term operation of petrochemical wastewater membrane treatment.

3.
J Colloid Interface Sci ; 671: 664-679, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-38820850

RESUMO

Bi2O2CO3/In(OH)3 (BON) photocatalysts were synthesized by a one-pot method and loaded onto polyvinylidene fluoride (PVDF) membranes to obtain a Bi2O2CO3/In(OH)3/PVDF (BON-M) catalytic membrane system. The catalytic membranes demonstrated complete degradation of tetracycline within 40 min under visible light. They demonstrated robust photocatalytic activity across a broad pH range (5-11) and in the presence of coexisting ions. The membranes demonstrated excellent self-cleaning performance. Following exposure to light, the irreversible contamination decreased from 27.1% to 4.7% and the membrane's permeability was almost completely restored. Moreover, the charge transfer mechanism at the S-scheme heterojunction interface of BON was demonstrated by Density functional theory and in-situ X-ray Photoelectron Spectroscopy characterisation, and the active sites involved in tetracycline's degradation were identified. Meanwhile, the mechanism of the "anemone effect" of BON-M was demonstrated in conjunction with Electron paramagnetic resonance, and the intrinsic Some factors enhancing the membranes' photocatalytic activity are specified.

4.
Water Res ; 256: 121581, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38614032

RESUMO

The autotrophic denitrification of coupled sulfur and natural iron ore can remove nitrogen and phosphorus from wastewater with low C/N ratios. However, the low solubility of crystalline Fe limits its bioavailability and P absorption capacity. This study investigated the effects of amorphous Fe in drinking water treatment residue (DWTR) and crystalline Fe in red mud (RM) on nitrogen and phosphorus removal during sulfur autotrophic processes. Two types of S-Fe cross-linked filler particles with three-dimensional mesh structures were obtained by combining sulfur with the DWTR/RM using the hydrogel encapsulation method. Two fixed-bed reactors, sulfur-DWTR autotrophic denitrification (SDAD) and sulfur-RM autotrophic denitrification (SRAD), were constructed and stably operated for 236 d Under a 5-8-h hydraulic retention time, the average NO3--N, TN, and phosphate removal rates of SDAD and SRAD were 99.04 %, 96.29 %, 94.03 % (SDAD) and 97.33 %, 69.97 %, 82.26 % (SRAD), respectively. It is important to note that fermentative iron-reducing bacteria, specifically Clostridium_sensu_stricto_1, were present in SDAD at an abundance of 58.17 %, but were absent from SRAD. The presence of these bacteria facilitated the reduction of Fe (III) to Fe (II), which led to the complete denitrification of the S-Fe (II) co-electron donor to produce Fe (III), completing the iron cycle in the system. This study proposes an enhancement method for sulfur autotrophic denitrification using an amorphous Fe substrate, providing a new option for the efficient treatment of low-C/N wastewater.


Assuntos
Processos Autotróficos , Desnitrificação , Ferro , Nitrogênio , Fósforo , Enxofre , Fósforo/metabolismo , Nitrogênio/metabolismo , Enxofre/metabolismo , Ferro/metabolismo , Ferro/química , Reatores Biológicos , Águas Residuárias/química , Eliminação de Resíduos Líquidos/métodos , Purificação da Água/métodos
5.
Sci Total Environ ; 926: 171806, 2024 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-38508266

RESUMO

Hospital wastewater treatment systems (HWTSs) are a significant source and reservoir of antibiotic resistance genes (ARGs) and a crucial hub for transmitting ARGs from clinical to natural environments. However, there is a lack of research on the antibiotic resistome of clinical wastewater in HWTSs. In this study, we used metagenomics to analyze the prevalence and abundance of ARGs in five typical HWTSs. A total of 17 antibiotics from six categories were detected in the five HWTSs; ß-lactam antibiotics were found at the highest concentrations, with up to 4074.08 ng·L-1. We further found a total of 21 ARG types and 1106 subtypes of ARGs with the highest percentage of multi-drug resistance genes (evgS, msbA, arlS, and baeS). The most abundant last-resort ARGs were mcr, which were detected in 100 % of the samples. HWTSs effluent is a major pathway for the transmission of last-resort ARGs into urban wastewater networks. The removal of antibiotics, antibiotic-resistant bacteria, and ARGs from HWTSs was mainly achieved by tertiary treatment, i.e., chlorine disinfection, but antibiotics and ARGs were still present in the HWTSs effluent or even increased after treatment. Moreover, antibiotics and heavy metals (especially mercury) in hospital effluents can exert selective pressure for antibiotic resistance, even at low concentrations. Qualitative analyses based on metagenome-assembled genome analysis revealed that the putative hosts of the identified ARGs are widely distributed among Pseudomonas, Acidovorax, Flavobacterium, Polaromonas, and Arcobacter. Moreover, we further assessed the clinical availability of ARGs and found that multidrug ARGs had the highest clinical relevance values. This study provides new impulses for monitoring and removing antibiotics and ARGs in the hospital sewage treatment process.


Assuntos
Antibacterianos , Purificação da Água , Águas Residuárias , Genes Bacterianos , Hospitais
6.
Water Res ; 253: 121358, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38402750

RESUMO

Membrane biofouling is a challenge to be solved for the stable operation of the seawater reverse osmosis (SWRO) membrane. This study explored the regulation mechanism of quorum sensing (QS) inhibition on microbial community composition and population-level behaviors in seawater desalination membrane biofouling. A novel antibiofouling SWRO membrane (MA_m) by incorporating one of quorum sensing inhibitors (QSIs), methyl anthranilate (MA) was prepared. It exhibited enhanced anti-biofouling performance than the exogenous addition of QSIs, showing long-term stability and alleviating 22 % decrease in membrane flux compared with the virgin membrane. The results observed that dominant bacteria Epsilon- and Gamma-proteobacteria (Shewanella, Olleya, Colwellia, and Arcobacter), which are significantly related to (P ≤ 0.01) the metabolic products (i.e., polysaccharides, proteins and eDNA), are reduced by over 80 % on the MA_m membrane. Additionally, the introduction of MA has a more significant impact on the QS signal-sensing pathway through binding to the active site of the transmembrane sensor receptor. It effectively reduces the abundance of genes encoding QS and extracellular polymeric substance (EPS) (exopolysaccharides (i.e., galE and nagB) and amino acids (i.e., ilvE, metH, phhA, and serB)) by up to 50 % and 30 %, respectively, resulting in a reduction of EPS by more than 50 %, thereby limiting the biofilm formation on the QSI-modified membrane. This study provides novel insights into the potential of QSIs to control consortial biofilm formation in practical SWRO applications.


Assuntos
Incrustação Biológica , Microbiota , Purificação da Água , Percepção de Quorum , Biofilmes , Matriz Extracelular de Substâncias Poliméricas , Osmose , Água do Mar/microbiologia , Membranas Artificiais , Purificação da Água/métodos
7.
Water Res ; 249: 120914, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38007899

RESUMO

The fouling of seawater reverse osmosis (SWRO) membranes remains a persistent challenge in desalination. Previous research has focused mainly on fouling separately; however, organic, inorganic, and biofouling can coexist and influence each other. Hence, in-depth study of the spatiotemporal changes in actual combined fouling in full-scale seawater desalination will provide more effective information for fouling investigation and control. In this study, we monitored (i) the operational performance of a full-scale desalination plant for 7 years and (ii) the development and characterization of membrane and spacer fouling at different locations of spiral-wound membrane modules sampled after 2.5-, 3.5-, and 7-year operation. The findings showed that (i) operational performance indicators declined with time (normalized flux 40 % reduction, salt rejection 2 % in 7 years), with a limited effect of the 20-day cleaning frequency, (ii) fouling accumulation in the membrane module mainly occurred at the feed side of the lead module and the microbial community in these area exhibited the highest diversity, (iii) the dominant microbial OTUs belonged mainly to Proteobacteria (43-70 %), followed by Bacteroidetes (10-11 %), (iv) Phylogenetic molecular ecological networks and Spearman correlation analysis revealed that Chloroflexi (Anaerolineae) and Planctomycetes were keystone species in maintaining the community structure and biofilm maturation and significantly impacted the foulant content on the SWRO membrane, even with low abundance, and that (v) fouling accumulation was composed of polysaccharides, soluble microbial products, marine humic acid-like substances, and inorganic Ca/Fe/Mg/Si dominate the fouling layer of both the membrane and spacer. Overall, variation partitioning analysis quantitatively describes the increasing contribution of biofouling over time. Ultimately, the organic‒inorganic-biofouling interaction (70 %) significantly contributed to the overall fouling of the membrane after 7 years of operation. These results can be used to develop more targeted fouling control strategies to optimize SWRO desalination plant design and operation.


Assuntos
Incrustação Biológica , Purificação da Água , Filogenia , Membranas Artificiais , Purificação da Água/métodos , Osmose , Água do Mar/química
8.
Environ Sci Ecotechnol ; 20: 100341, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38094258

RESUMO

Municipal wastewater treatment plays an indispensable role in enhancing water quality by eliminating contaminants. While the process is vital, its environmental footprint, especially in terms of greenhouse gas (GHG) emissions, remains underexplored. Here we offer a comprehensive assessment of GHG emissions from wastewater treatment plants (WWTPs) across China. Our analyses reveal an estimated 1.54 (0.92-2.65) × 104 Gg release of GHGs (CO2-eq) in 2020, with a dominant contribution from N2O emissions and electricity consumption. We can foresee a 60-65% reduction potential in GHG emissions with promising advancements in wastewater treatment, such as cutting-edge biological techniques, intelligent wastewater strategies, and a shift towards renewable energy sources.

9.
J Environ Manage ; 348: 119171, 2023 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-37832287

RESUMO

Membrane fouling caused by inorganic ions and natural organic matters (NOMs) has been a severe issue in membrane distillation. Microbubble aeration (MB) is a promising technology to control membrane fouling. In this study, MB aeration was introduced to alleviate humic acid (HA) composited fouling during the treatment of simulative reverse osmosis concentrate (ROC) by vacuum membrane distillation (VMD). The objective of this work was to explore the HA fouling inhibiting effect by MB aeration and discuss its mechanism from the interfacial point of view. The results showed that VMD was effective for treating ROC, followed by a severe membrane fouling aggravated with the addition of 100 mg/L HA in feed solution, resulting in 45.7% decline of membrane flux. Analysis using the Derjaguin-Landau-Verwey-Overbeek (DLVO) theory and zeta potential distribution of charged particles proved the coexistence of HA and inorganic cations (especially Ca2+), resulting in more serious membrane fouling. The introduction of MB aeration exhibited excellent alleviating effect on HA-inorganic salt fouling, with the normalized flux increased from 19.7% to 37.0%. The interfacial properties of MBs played an important role, which altered the zeta potential distributions of charged particles in HA solution, indicating that MBs adhere the HA complexations. Furthermore, this mitigating effect was limited at high inorganic cations concentration. Overall, MBs could change the potential characteristics of HA complexes, which also be used for other similar membrane fouling alleviation.


Assuntos
Substâncias Húmicas , Purificação da Água , Substâncias Húmicas/análise , Destilação/métodos , Microbolhas , Membranas Artificiais , Purificação da Água/métodos , Cátions
10.
Sci Total Environ ; 902: 166081, 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-37544437

RESUMO

The pattern of antibiotic resistance assembly and their unclear transfer in a soil-lettuce system render the treated erythromycin fermentation residue (EFR) land application risky. Herein, the antibiotic resistance genes (ARGs), mobile gene elements, and microbial communities were examined under erythromycin stress at three stages of lettuce growth. Erythromycin exhibited degradation rates of 99.4 % in soils for 60 d, with little uptake in the seedling tissues, reaching a 0.11-0.71 bioconcentration factor range. The EFR application rate must be limited <1 % to avoid human exposure risk. The diversity, biotic networks complexity, and edaphic ARG abundances of the rhizospheric microbial communities increased at the early stage, but returned to the control levels at the mature stage. The Planomicrobium and Pseudomonas bacterial genera were important biotic factors for erythromycin variation. Thirty-three MLSB genes (macrolide, lincosamide, and streptogramin B) conferring resistance to erythromycin were detected in soil, but only two endophytic ARGs (mphA-01 and ermX) were identified, with members of the Microvirga genus being the potential hosts. Partial least-squares path modeling suggested that erythromycin concentration was the main factor for endophytic ARGs evolution. This study highlighted the leaf endophytic ARG emergence and potential exposure human risks majorly caused by the drug traces in antibiotic fermentation residues.


Assuntos
Eritromicina , Lactuca , Humanos , Genes Bacterianos , Solo/química , Fermentação , Microbiologia do Solo , Antibacterianos/farmacologia , Resistência Microbiana a Medicamentos/genética
11.
Water Res ; 241: 120166, 2023 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-37290196

RESUMO

Dissolved organic matters (DOM) are widely present in different water sources, causing significant effects on water treatment processes. Herein, the molecular transformation behavior of DOM during peroxymonosulfate (PMS) activation by biochar for organic degradation in a secondary effluent were comprehensively analyzed. Evolution of DOM was identified and inhibition mechanisms to organic degradation were elucidated. DOM underwent oxidative decarbonization (e.g., -C2H2O, -C2H6, -CH2 and -CO2), dehydrogenation (-2H) and dehydration reactions by ·OH and SO4·-. N and S containing compounds witnessed deheteroatomisation (e.g., -NH, -NO2+H, -SO2, -SO3, -SH2), hydration (+H2O) and N/S oxidation reactions. Among DOM, CHO-, CHON-, CHOS-, CHOP- and CHONP-containing molecules showed moderate inhibition while condensed aromatic compounds and aminosugars exhibited strong and moderate inhibition effects on contaminant degradation. The fundamental information could provide references for the rational regulation of ROS composition and DOM conversion process in a PMS system. This in turn offered theoretical guidance to minimize the interference of DOM conversion intermediates on PMS activation and degradation of target pollutants.


Assuntos
Matéria Orgânica Dissolvida , Poluentes Ambientais , Peróxidos , Compostos Orgânicos
12.
Environ Sci Technol ; 57(27): 10117-10126, 2023 07 11.
Artigo em Inglês | MEDLINE | ID: mdl-37364020

RESUMO

Electrocatalytic reduction of nitrate to NH3 (NO3RR) on Cu offers sustainable NH3 production and nitrogen recycling from nitrate-contaminated water. However, Cu affords limited NO3RR activity owing to its unfavorable electronic state and the slow proton transfer on its surface, especially in neutral/alkaline media. Furthermore, although a synchronous "NO3RR and NH3 collection" system has been developed for nitrogen recycling from nitrate-laden water, no system is designed for natural water that generally contains low-concentration nitrate. Herein, we demonstrate that depositing Cu nanoparticles on a TiO2 support enables the formation of electron-deficient Cuδ+ species (0 < δ ≤ 2), which are more active than Cu0 in NO3RR. Furthermore, TiO2-Cu coupling induces local electric-field enhancement that intensifies water adsorption/dissociation at the interface, accelerating proton transfer for NO3RR on Cu. With the dual enhancements, TiO2-Cu delivers an NH3-N selectivity of 90.5%, mass activity of 41.4 mg-N h gCu-1, specific activity of 377.8 mg-N h-1 m-2, and minimal Cu leaching (<25.4 µg L-1) when treating 22.5 mg L-1 of NO3--N at -0.40 V, outperforming most of the reported Cu-based catalysts. A sequential NO3RR and NH3 collection system based on TiO2-Cu was then proposed, which could recycle nitrogen from nitrate-contaminated water under a wide concentration window of 22.5-112.5 mg L-1 at a rate of 209-630 mgN m-2 h-1. We also demonstrated this system could collect 83.9% of nitrogen from NO3--N (19.3 mg L-1) in natural lake water.


Assuntos
Nanopartículas , Nitratos , Nitratos/química , Prótons , Cobre , Nitrogênio , Água
13.
BMC Med Res Methodol ; 23(1): 108, 2023 05 02.
Artigo em Inglês | MEDLINE | ID: mdl-37131135

RESUMO

BACKGROUND: Despite the extensive research on data mining algorithms, there is still a lack of a standard protocol to evaluate the performance of the existing algorithms. Therefore, the study aims to provide a novel procedure that combines data mining algorithms and simplified preprocessing to establish reference intervals (RIs), with the performance of five algorithms assessed objectively as well. METHODS: Two data sets were derived from the population undergoing a physical examination. Hoffmann, Bhattacharya, Expectation Maximum (EM), kosmic, and refineR algorithms combined with two-step data preprocessing respectively were implemented in the Test data set to establish RIs for thyroid-related hormones. Algorithm-calculated RIs were compared with the standard RIs calculated from the Reference data set in which reference individuals were selected following strict inclusion and exclusion criteria. Objective assessment of the methods is implemented by the bias ratio (BR) matrix. RESULTS: RIs of thyroid-related hormones are established. There is a high consistency between TSH RIs established by the EM algorithm and the standard TSH RIs (BR = 0.063), although EM algorithms seems to perform poor on other hormones. RIs calculated by Hoffmann, Bhattacharya, and refineR methods for free and total triiodo-thyronine, free and total thyroxine respectively are close and match the standard RIs. CONCLUSION: An effective approach for objectively evaluating the performance of the algorithm based on the BR matrix is established. EM algorithm combined with simplified preprocessing can handle data with significant skewness, but its performance is limited in other scenarios. The other four algorithms perform well for data with Gaussian or near-Gaussian distribution. Using the appropriate algorithm based on the data distribution characteristics is recommended.


Assuntos
Glândula Tireoide , Hormônios Tireóideos , Adulto , Humanos , Pessoa de Meia-Idade , Valores de Referência , Mineração de Dados , Tireotropina
14.
Environ Sci Technol ; 57(17): 7063-7073, 2023 05 02.
Artigo em Inglês | MEDLINE | ID: mdl-37018050

RESUMO

Pyrolysis of oily sludge (OS) is a feasible technology to match the principle of reduction and recycling; however, it is difficult to confirm the feasible environmental destination and meet the corresponding requirements. Therefore, an integrated strategy of biochar-assisted catalytic pyrolysis (BCP) of OS and residue utilization for soil reclamation is investigated in this study. During the catalytic pyrolysis process, biochar as a catalyst intensifies the removal of recalcitrant petroleum hydrocarbons at the expense of liquid product yield. Concurrently, biochar as an adsorbent can inhibit the release of micromolecular gaseous pollutants (e.g. HCN, H2S, and HCl) and stabilize heavy metals. Due to the assistance of biochar, pyrolysis reactions of OS are more likely to occur and require a lower temperature to achieve the same situation. During the soil reclamation process, the obtained residue as a soil amendment can not only provide a carbon source and mineral nutrients but can also improve the abundance and diversity of microbial communities. Thus, it facilitates the plant germination and the secondary removal of petroleum hydrocarbons. The integrated strategy of BCP of OS and residue utilization for soil reclamation is a promising management strategy, which is expected to realize the coordinated and benign disposal of more than one waste.


Assuntos
Petróleo , Solo , Solo/química , Esgotos/química , Pirólise , Carvão Vegetal , Óleos , Hidrocarbonetos
15.
Environ Pollut ; 323: 121293, 2023 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-36804559

RESUMO

One of the major pollutants influencing urban air quality in China is O3. O3 is the second most important pollutant affecting air quality in Shijiazhuang, which is the third largest city in the Beijing-Tianjin-Hebei area and the provincial capital of Hebei province. To fully understand the characteristics of O3 and volatile organic compounds (VOCs), which are O3 precursors, and the role of VOCs to ozone formation, we measured the hourly concentrations of O3 and 85 VOCs in Shijiazhuang continuously from January to November 2020, and the concentration characteristics of both together with the chemical reactivity and sources of VOCs were analyzed from a seasonal perspective. The O3 concentration in Shijiazhuang showed a phenomenon of high summer and low winter, and the VOCs showed a phenomenon of high winter and low spring. In the summer when the O3 exceedance rate is the highest, the time-domain variation characteristics of O3 were analyzed by wavelet analysis model, and the main periods controlling the O3 concentration variation in Shijiazhuang in summer 2020 were 52 days, 32 days, 19 days and 12 days. The maximum incremental reactivity (MIR) and propylene equivalence method indicated ethene, propylene and 1-pentene were common substances in the top five species of each season. The T/B, Iso-p/N-p, Iso-p/E, N-p/E, and positive matrix factorization (PMF) model showed that industrial source (18.62%-22.03%) and vehicle emission (13.20%-17.69%) were the major VOCs sources in Shijiazhuang. Therefore, to control the O3 concentration in Shijiazhuang, it is necessary to decrease alkenes emissions as well as VOCs from industrial source and vehicle emission.


Assuntos
Poluentes Atmosféricos , Ozônio , Compostos Orgânicos Voláteis , Pequim , Emissões de Veículos/análise , Poluentes Atmosféricos/análise , Compostos Orgânicos Voláteis/análise , Estações do Ano , Urbanização , China , Ozônio/análise , Monitoramento Ambiental
16.
J Hazard Mater ; 449: 130971, 2023 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-36805443

RESUMO

The vacancy defects in heterogeneous catalysts have received extensive attention for persulfate (PS) activation. Vacancy defects can tune the electronic structure of metal oxides and generate unsaturated coordination sites. Meanwhile, the adsorption energy of reactants on catalyst surface is optimized. Thereby, the reaction energy barrier between catalysts and PS decreases, which could promote catalytic activation and accelerate pollutants degradation. Nowadays, oxygen vacancy (OV), nitrogen vacancy (NV), sulfur vacancy (SV), selenium vacancy (SeV) and titanium vacancy (TiV) have been widely studied with great potential for water remediation. So far, no review was reported regarding the vacancy activated persulfate systems. This paper summarized the types, preparation, mechanism and applications of vacancy in PS systems systematically. In addition, we put forward possible development of vacancy engineering in PS activation systems. It is expected that this review will contribute to the controllable synthesis and applications of vacancies in catalysts for PS activation and contaminants removal.

17.
Sci Total Environ ; 872: 162217, 2023 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-36791865

RESUMO

The peroxymonosulfate (PMS) process may be hindered severely due to natural organic matter (NOM) conversion in the treatment of emerging pollutants from river water, becoming a critical engineering and technical issue. In this study, a Fe(II)-induced river water (RW)/PMS catalytic system was constructed for investigating molecular transformation of NOM and related influence mechanism to sulfamethoxazole (SMX) degradation. Fourier transform ion cyclotron resonance mass spectrometry (FTICR-MS) analysis indicated that NOM molecules containing no more than one heteroatom in river may be attacked by hydroxyl radicals (OH) and then polymerized, converting into molecules with two or three heteroatoms during PMS oxidation. Based on the correlation analysis, CHONP-NOM, CHOSP-NOM and CHONSP-NOM showed a significant inhibition against SMX degradation, while CHONS-NOM exhibited a moderate inhibitory effect. Besides, more condensed aromatic structures, carbohydrates and tannins were generated via reactive species (OH and sulfate radicals (SO4-)) oxidation, radical addition and polymerization reactions. Notably, condensed aromatic structures, carbohydrates and tannins presented weak, modest and strong inhibition to SMX degradation, respectively. Based on the current results, the inhibition of target pollutants degradation would be mitigated via regulation of NOM molecules in a Fe(II)-induced PMS activation system, providing valuable information to reduce NOM impact. In addition, this study paves the way to achieve efficient removal of emerging pollutants from river water.

18.
J Neuroimmunol ; 375: 578015, 2023 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-36682196

RESUMO

BACKGROUND: The association of iron metabolism parameters with disease severity and outcome in myasthenia gravis (MG) patients has not been reported. This study was conducted to determined clinical factors including iron metabolism parameters correlated with disease severity and future outcome in non-anemic immunotherapy-naïve MG patients first receiving immunotherapy. MATERIAL AND METHODS: One hundred and ten patients were included at baseline to explore predictor variables associated with disease severity represented by variables derived from MG activities of daily living (MG-ADL) score using multivariate logistic regression, after which 103 and 98 patients were included respectively in multivariate survival analyses at 6-month and 12-month follow-up to identify predictors for minimal manifestation status (MMS) after starting immunotherapy. RESULTS: Higher ferritin level was independently associated with higher risk of severe generalized disease in non-anemic immunotherapy-naïve MG patients. Total iron binding capacity <250 µg/dL and the interval between onset and immunotherapy <1 year were independent predictors for MMS at 6-month and 12-month follow-up after initiating immunotherapy. Transferrin <2.00 g/L was an independent predictor for MMS at 12-month follow-up. CONCLUSION: Iron metabolism parameters might be promising biomarkers for evaluating disease severity and guiding therapeutic decision in MG patients.


Assuntos
Atividades Cotidianas , Miastenia Gravis , Humanos , Estudos de Coortes , Miastenia Gravis/tratamento farmacológico , Gravidade do Paciente , Ferro/uso terapêutico
20.
J Hazard Mater ; 446: 130705, 2023 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-36587600

RESUMO

Antibiotic fermentation residue is a key issue for the sustainable operation of pharmaceutical companies, and its improper disposal may cause antibiotic resistance transfer in the environment. However, little is known about the resource recycling strategy of this pharmaceutical waste. Herein, we used hydrothermal spray-dried (HT+SD) and multi-plate dryer (MD) methods to produce bio-organic fertilizers and applied them to an internal recycling model of a field trial. The concentrations of antibiotics (penicillin, cephalosporin, and erythromycin) in the bio-fertilizer, wastewater, and exhaust gas were in the range of 0.002-0.68 mg/kg, ≤ 0.35 ng/mL, and 0.03-0.89 ng/mL, respectively. The organic matter and total nitrogen, phosphorus, and potassium contents were approximately 80% and 10%, respectively. The soil bacterial community was similar among the fertilizer treatments in the same crop cultivation. A total of 233 antibiotic resistance genes (ARGs) and 43 mobile genetic elements (MGEs) were detected, including seven Rank I ARGs and five Rank II ARGs. Random forest analysis showed that gene acc(3)-Via and plasmid trb-C were biomarkers, for which the resistance and the transfer mechanisms were antibiotic inactivation and conjugation, respectively. The results imply that AFR recycling disposal mode is a promising prospect for pharmaceutical waste management.


Assuntos
Antibacterianos , Fertilizantes , Antibacterianos/farmacologia , Antibacterianos/análise , Fermentação , Fazendas , Fertilizantes/análise , Genes Bacterianos , Esterco
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