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1.
Environ Geochem Health ; 46(5): 165, 2024 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-38592368

RESUMO

Soil pollution around Pb-Zn smelters has attracted widespread attention around the world. In this study, we compiled a database of eight potentially toxic elements (PTEs) Pb, Zn, Cd, As, Cr, Ni, Cu, and Mn in the soil of Pb-Zn smelting areas by screening the published research papers from 2000 to 2023. The pollution assessment and risk screening of eight PTEs were carried out by geo-accumulation index (Igeo), potential ecological risk index (PERI) and health risk assessment model, and Monte Carlo simulation employed to further evaluate the probabilistic health risks. The results suggested that the mean values of the eight PTEs all exceeded the corresponding values in the upper crust, and more than 60% of the study sites had serious Pb and Cd pollution (Igeo > 4), with Brazil, Belgium, China, France and Slovenia having higher levels of pollution than other regions. Besides, PTEs in smelting area caused serious ecological risk (PERI = 10912.12), in which Cd was the main contributor to PREI (86.02%). The average hazard index (HI) of the eight PTEs for adults and children was 7.19 and 9.73, respectively, and the average value of total carcinogenic risk (TCR) was 4.20 × 10-3 and 8.05 × 10-4, respectively. Pb and As are the main contributors to non-carcinogenic risk, while Cu and As are the main contributors to carcinogenic risk. The probability of non-carcinogenic risk in adults and children was 84.05% and 97.57%, while carcinogenic risk was 92.56% and 79.73%, respectively. In summary, there are high ecological and health risks of PTEs in the soil of Pb-Zn smelting areas, and Pb, Cd, As and Cu are the key elements that cause contamination and risk, which need to be paid attention to and controlled. This study is expected to provide guidance for soil remediation in Pb-Zn smelting areas.


Assuntos
Cádmio , Chumbo , Adulto , Criança , Humanos , Chumbo/toxicidade , Carcinogênese , Carcinógenos , Poluição Ambiental , Probabilidade , Medição de Risco , Solo , Zinco
2.
Sci Total Environ ; 928: 172255, 2024 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-38599412

RESUMO

This study attempts to bridge the current research gaps related to the environmental burdens of low-rank coal (LRC) and sewage sludge (SS) co-pyrolysis potentially. The life cycle assessment (LCA), energy recovery and sensitivity analysis were investigated for different proportions of LRC and SS (co-)pyrolysis. The results showed that the LRC/SS pyrolysis mitigated the environmental burden with an average improvement of 43 % across 18 impact categories compared with SS pyrolysis. The best net values of energy and carbon credits were identified in SL-4 with -3.36 kWh/kg biochar and -1.10 CO2-eq/kg biochar, respectively. This study firstly proposed an optimal LRC/SS co-feed proportion at 3 to 7, which achieves the acceptable environmental burden and satisfactory energy recovery. Moreover, sensitivity analysis demonstrated this proportion is robust and adaptable. LRC/SS co-pyrolysis is a promising and sustainable alternative for SS disposal, which could meet the imperative of carbon emission mitigation and resource recycling.

3.
J Colloid Interface Sci ; 667: 303-311, 2024 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-38640650

RESUMO

Metal selenides have emerged as promising Na-storage anode materials owing to their substantial theoretical capacity and high cost-effectiveness. However, the application of metal selenides is hindered by inferior electronic conductivity, huge volume variation, and sluggish kinetics of ionic migration. In response to these challenges, herein, a hierarchical hollow tube consisting of FeSe2 nanosheets and Se quantum dots anchored within a carbon skeleton (HT-FeSe2/Se/C) is strategically engineered and synthesized. The most remarkable feature of HT-FeSe2/Se/C is the introduction of Se quantum dots, which could lead to high electron density near the Fermi level and significantly enhance the overall charge transfer capability of the electrode. Moreover, the distinctive hollow tubular structure enveloped by the carbon skeleton endows the HT-FeSe2/Se/C anode with robust structural stability and fast surface-controlled Na-storage kinetics. Consequently, the as-synthesized HT-FeSe2/Se/C demonstrates a reversible capacity of 253.5 mAh/g at a current density of 5 A/g and a high specific capacity of 343.9 mAh/g at 1 A/g after 100 cycles in sodium-ion batteries (SIBs). Furthermore, a full cell is assembled with HT-FeSe2/Se/C as the anode, and a vanadium-based cathode (Na3V2(PO4)2O2F), showcasing a high specific capacity of 118.1 mAh/g at 2 A/g. The excellent performance of HT-FeSe2/Se/C may hint at future material design strategies and advance the development and application of SIBs.

4.
J Hazard Mater ; 470: 134060, 2024 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-38552395

RESUMO

Reverse osmosis (RO)-based treatment of municipal wastewater effluent allows for potable reuse, but this process generates reverse osmosis concentrate (ROC) that needs further treatment before disposal. This study investigated the application of UV-based advanced oxidation processes (AOPs) to degrade nine contaminants of emerging concern (CECs) from real ROC waste streams, using UV-only and UV-AOPs with hydrogen peroxide, free chlorine, and persulfate. Dissolved organic matter (DOM) in ROC was characterized using fluorescence excitation emission matrix data and analyzed by a four-component parallel factor (PARAFAC) analysis model. UV-only treatment showed considerable removal of CECs that displayed high values of quantum yields and molar absorption coefficients. UV-AOP treatment of ROC exhibited heavy scavenging of reactive species during CEC degradation. A probe-based approach established that hydroxyl radical was the dominant reactive species in all UV-AOPs. A kinetic analysis of PARAFAC components of DOM showed that the visible humic-like and protein-like components exhibited the higher reaction kinetics compared to UV humic-like and nutrient-like components. The strong linear correlation of protein-like component and seven of the nine CECs across multiple AOPs indicated that they have similar reactivity, enabling the establishment of chemical-reactivity based surrogates for prediction CEC fate in ROC wastes.

5.
Int J Biol Macromol ; 262(Pt 2): 130181, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38360240

RESUMO

Poly(butylene diglycolate-co-furandicarboxylate) (PBDF) is a newly developed biodegradable copolyester. Candida antarctica lipase B (CALB) has been identified as an effective catalyst for PBDF degradation. The mechanism is elucidated using a combination of molecular dynamics simulations and quantum chemistry approaches. The findings unveil a four-step catalytic reaction pathway. Furthermore, bond analysis, charge and interaction analysis are conducted to gain a more comprehensive understanding of the PBDF degradation process. Additionally, through the introduction of single-point mutations to crucial residues in CALB's active sites, two mutants, T138I and D134I, are discovered to exhibit improved catalytic efficiency. These significant findings contribute to the advancement of our comprehension concerning the molecular mechanism of underlying copolyesters degradation, while also presenting a novel approach for expediting the degradation rate by the CALB enzyme modification.


Assuntos
Proteínas Fúngicas , Lipase , Lipase/química , Proteínas Fúngicas/química , Simulação de Dinâmica Molecular , Domínio Catalítico
6.
Ann Med ; 55(2): 2276816, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37930932

RESUMO

BACKGROUND/AIMS: Acute pancreatitis is a common condition of the digestive system, but sometimes it develops into severe cases. In about 10-20% of patients, necrosis of the pancreas or its periphery occurs. Although most have aseptic necrosis, 30% of cases will develop infectious necrotizing pancreatitis. Infected necrotizing pancreatitis (INP) requires a critical treatment approach. Minimally invasive surgical approach (MIS) and endoscopy are the management methods. This meta-analysis compares the outcomes of MIS and endoscopic treatments. METHODS: We searched a medical database until December 2022 to compare the results of endoscopic and MIS procedures for INP. We selected eligible randomized controlled trials (RCTs) that reported treatment complications for the meta-analysis. RESULTS: Five RCTs comparing a total of 284 patients were included in the meta-analysis. Among them, 139 patients underwent MIS, while 145 underwent endoscopic procedures. The results showed significant differences (p < 0.05) in the risk ratios (RRs) for major complications (RR: 0.69, 95% confidence interval (CI): 0.49-0.97), new onset of organ failure (RR: 0.29, 95% CI: 0.11-0.82), surgical site infection (RR: 0.26, 95% CI: 0.07-0.92), fistula or perforation (RR: 0.27, 95% CI: 0.12-0.64), and pancreatic fistula (RR: 0.14, 95% CI: 0.05-0.45). The hospital stay was significantly shorter for the endoscopic group compared to the MIS group, with a mean difference of 6.74 days (95% CI: -12.94 to -0.54). There were no significant differences (p > 0.05) in the RR for death, bleeding, incisional hernia, percutaneous drainage, pancreatic endocrine deficiency, pancreatic exocrine deficiency, or the need for enzyme use. CONCLUSIONS: Endoscopic management of INP performs better compared to surgical treatment due to its lower complication rate and higher patient life quality.


Assuntos
Endoscopia , Pancreatite Necrosante Aguda , Humanos , Ensaios Clínicos Controlados Aleatórios como Assunto , Endoscopia/métodos , Pancreatite Necrosante Aguda/cirurgia , Pâncreas/cirurgia , Necrose , Resultado do Tratamento
7.
Huan Jing Ke Xue ; 44(9): 5231-5241, 2023 Sep 08.
Artigo em Chinês | MEDLINE | ID: mdl-37699841

RESUMO

Perfluoroalkyl and polyfluoroalkyl substances (PFAS) are refractory organic pollutants, which are characterized by ubiquity, bioaccumulation, and biological toxicity. To explore the biotoxic effects of PFAS on fish, this study reviewed 64 publications. The toxicity of PFAS on functional traits of fish exposed to PFAS was analyzed based on Meta-analysis combined with effect sizes, which provided reference for the toxicity assessment of PFAS and was conducive to the priority control and management of PFAS pollution. The results showed that:① of the 12 functional traits studied, seven were found to be vulnerable in fish; the order of toxicity response was malformation (lnRR=-2.5599), development (lnRR=-0.4103), cell damage (lnRR=-0.3962), reproduction (lnRR=-0.3724), thyroid response (lnRR=-0.2492), growth (lnRR=-0.2194), and survival (lnRR=-0.2192). ② The aquatic toxicity of PFAS was significantly affected by the sex and developmental stage of fish. PFAS tended to have adverse effects on female fish (lnRR=-0.1628), and the physiological function of embryos was most significantly affected by PFAS (lnRR=-0.3553). ③ A total of 13 PFAS were involved in the study, among which PFAS with sulfonate groups and long-chains were more likely to have significant toxicity to the functional traits of fish (P<0.05).④ Existing data revealed that PFAS tended to produce acute toxicity to fish at medium and low concentrations (0.01-10 mg·L-1, P<0.05).


Assuntos
Poluentes Ambientais , Fluorocarbonos , Animais , Feminino , Alcanossulfonatos , Poluentes Ambientais/toxicidade , Poluição Ambiental , Peixes , Fluorocarbonos/toxicidade , Masculino
8.
Int J Biol Macromol ; 242(Pt 2): 124756, 2023 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-37178891

RESUMO

Hemoglobin is essential for carrying oxygen (O2) in the blood. However, its ability to bind excessively to carbon monoxide (CO) makes it susceptible to CO poisoning. To reduce the risk of CO poisoning, Cr-based heme and Ru-based heme were selected from among many transition metal-based hemes based on their characteristics of adsorption conformation, binding intensity, spin multiplicity, and electronic properties. The results showed that hemoglobin modified by Cr-based heme and Ru-based heme had strong anti-CO poisoning abilities. The Cr-based heme and Ru-based heme exhibited much stronger affinity for O2 (-190.67 kJ/mol and -143.18 kJ/mol, respectively) than Fe-based heme (-44.60 kJ/mol). Moreover, Cr-based heme and Ru-based heme exhibited much weaker affinity for CO (-121.50 kJ/mol and -120.88 kJ/mol, respectively) than their affinity for O2, suggesting that they were less likely to cause CO poisoning. The electronic structure analysis also supported this conclusion. Additionally, molecular dynamics analysis showed that hemoglobin modified by Cr-based heme and Ru-based heme was stable. Our findings offer a novel and effective strategy for enhancing the reconstructed hemoglobin's ability to bind O2 and reduce its potential for CO poisoning.


Assuntos
Antitoxinas , Rutênio , Cromo/toxicidade , Hemoglobinas , Oxigênio/química , Heme/química , Monóxido de Carbono/química , Monóxido de Carbono/metabolismo
9.
Ecotoxicol Environ Saf ; 244: 114035, 2022 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-36058162

RESUMO

Coagulation is an effective preliminary treatment process for textile wastewater. In order to evaluate the effectiveness of the coagulation process, we performed quantitative structure activity relationship (QSAR) analyses with total organic carbon (TOC) removal rates (Rexp) as an index by three different coagulants (AlCl3, FeCl3, and MgCl2). The experimental results showed that the average Rexp of the three coagulants was 39.12% ± 2.60%, 51.60% ± 2.88%, and 49.95% ± 3.17%. Subsequently, 42 molecular descriptors of dye molecules were calculated by quantitative calculation softwares Gaussian 09, Material Studio 7.0, and Multiwfn 3.7, and then QSAR models were constructed by a multiple linear regression (MLR) method for the three coagulation systems. The developed QSAR models demonstrated excellent stability, robustness, and predictability with values of R2 = 0.7677, 0.8015, and 0.7035, Q2INT = 0.6067, 0.7026, and 0.5898, Q2EXT = 0.5505, 0.5076, and 0.5697, respectively. Based on the analysis of quantum parameters, the coagulation mechanism for AlCl3, FeCl3 is primarily electrostatic adsorption as well as hydrogen bonding, while MgCl2 coagulates dyes mainly by electrostatic adsorption. This study provides an assessment of the removal rules and a feasible method for predicting dye removal rates in AlCl3, FeCl3, and MgCl2 coagulation process.


Assuntos
Relação Quantitativa Estrutura-Atividade , Águas Residuárias , Carbono , Corantes/química , Têxteis , Águas Residuárias/química
10.
J Hazard Mater ; 438: 129448, 2022 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-35803185

RESUMO

QSAR modeling could be a promising tool for guiding the development of novel and cost-effective environmental technologies. As an example, it could be widely used to analyze the degradation rules of organic pollutants in various decomposition methods. However, a lack of systematic research on a particular removal method is significant in revealing the decomposition rule of pollutants more accurately and guiding industrial applications. In this study, six coagulation systems (MnO2/Fe(OH)3/AlCl3/FeCl3/CaCl2/MgCl2) were used as examples to remove 38 dyes under three pH conditions, and the characteristics and differences of these systems were explored by QSAR modeling. The results showed that the removal effect by MnO2 under acidic and neutral conditions and Fe(OH)3 under acidic conditions were quantitatively described mainly by bond order (BO) and Fukui index (f (+) and f (0)), which reflected that oxidative degradation dominated. In contrast, most of the critical parameters of other systems were molecular descriptors represented by ∑q(O) (the total charge of all the oxygen atoms in the molecule) and SAA (surface area of a molecule), which reflected that electrostatic adsorption and hydrogen-bond adsorption processes dominated.


Assuntos
Poluentes Ambientais , Poluentes Químicos da Água , Corantes/química , Compostos de Manganês , Óxidos , Relação Quantitativa Estrutura-Atividade , Poluentes Químicos da Água/química
11.
Ecotoxicol Environ Saf ; 240: 113693, 2022 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-35653976

RESUMO

Coagulation is the most widely used method in the treatment of printing and dying wastewater. To better understand the relationship between the coagulation effect and dye molecular structures, quantitative structure activity relationship (QSAR) analyses were performed to elucidate the factors affecting the coagulation in ferric chloride (FeCl3) coagulation process. First, the coagulation experiments on 38 dye molecules were conducted to determine their color removal rates (Rexp) by FeCl3 under different pH conditions (i.e., pH = 4 and 10). The results showed that the average Rexp of dyes were 41.36% ± 2.40% at pH value of 4 and 55.70% ± 2.83% at pH value of 10. Subsequently, a multiple linear regression (MLR) method was used to construct QSAR models based on Rexp and 42 molecular parameters calculated by Gaussian 09, Materials Studio 7.0 and Multiwfn. The developed QSAR models exhibited excellent stability, reliability, and robustness with values of R2 = 0.7950, 0.8170, Q2INT = 0.6401, 0.7382, Q2EXT = 0.5168, 0.5441, at pH values of 4 and 10, respectively. Through analysis of quantum parameter values, electrostatic adsorption and hydrogen bonding adsorption were primarily responsible for the coagulation process. Therefore, this study could be useful in providing critical information for evaluating the removal efficiency and a feasible way to predict the removal rate of dyes by FeCl3 when no coagulation experiments were conducted.


Assuntos
Relação Quantitativa Estrutura-Atividade , Águas Residuárias , Adsorção , Corantes , Reprodutibilidade dos Testes , Águas Residuárias/química
12.
J Hazard Mater ; 430: 128269, 2022 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-35158249

RESUMO

Iron-impregnated biochar-activated urea-hydrogen peroxide (FB-activated UHP) is a potential in-situ technology for simultaneously reducing soil sulfonamide antibiotic contaminants and improving soil fertility. To better understand the degradation of sulfonamide antibiotics by FB-activated UHP, a two-dimensional quantitative structure-activity relationship (2D-QSAR) model based on quantum chemical parameters and a three-dimensional QSAR (3D-QSAR) model based on molecular force field were developed to investigate the factors influencing the removal efficiencies (Re%). The optimal 2D-QSAR model was Re%= 0.858-8.930 E-5 EB3LYP-0.175 f(+)x with the evaluation indices of R2= 0.732, q2= 0.571, and Qext2= 0.673. The given 2D-QSAR model indicated that the molecular size (EB3LYP) and Fukui index with respect to nucleophilic attack (f(+)) were intrinsic factors influencing Re%. Three degradation pathways were subsequently proposed based on the f(+) distribution. Compared to the 2D-QSAR model, the developed 3D-QSAR model exhibited a better predictive ability, with the evaluation indices of R2= 0.989, q2= 0.696, and SEE= 0.001. The analysis of field contribution rates suggested that electrostatic field (48.2%), hydrophobic field (25.3%), and hydrogen-bond acceptor field (12.7%) were the main factors influencing Re%. These findings generated critical information for evaluating the degradation mechanisms/rules and provided theoretical bases for initially estimating the Re% of sulfonamide antibiotics undergoing FB-activated UHP process.


Assuntos
Peróxido de Hidrogênio , Relação Quantitativa Estrutura-Atividade , Antibacterianos , Peróxido de Carbamida , Carvão Vegetal , Peróxido de Hidrogênio/química , Ferro , Modelos Moleculares , Sulfonamidas
13.
Nephrology (Carlton) ; 27(2): 126-132, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34545979

RESUMO

Sodium-glucose cotransporter-2 (SGLT2) inhibitors represent novel hypoglycemic drugs for the treatment of adult diabetes that have shown considerable potential for cardioprotection and renoprotection. This new drug can inhibit SGLT2 at the proximal tubule, increase glucosuria and natriuresis, and thus decreases the serum glucose level and blood pressure. Furthermore, the tubuloglomerular feedback activated by the natriuresis can decrease glomerular hyperfiltration, acknowledged as the main foundation of renoprotection. Several studies have confirmed the protective effects of SGLT2 inhibitors on the kidneys of adult diabetic patients and those with non-diabetic nephropathy; however, limited researches are seen in paediatric patients. In this review, we have summarized the mechanisms of action of SGLT2 inhibitors, the current experiences in adults, results of exploratory studies in children, and adverse events & obstacles of paediatric use. We further explore the potential and possible future research direction of SGLT2 inhibitors in paediatric diseases.


Assuntos
Nefropatias Diabéticas/prevenção & controle , Nefropatias/prevenção & controle , Inibidores do Transportador 2 de Sódio-Glicose/uso terapêutico , Criança , Humanos
14.
Water Res ; 204: 117585, 2021 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-34478993

RESUMO

Disposal of reverse osmosis concentrate (ROC) from advanced water purification facilities is a challenge associated with the implementation of reverse osmosis-based treatment of municipal wastewater effluent for potable reuse. In particular, the dissolved organic matter (DOM) present in ROC diminishes the quality of the receiving water upon environmental disposal and affects the toxicity, fate, and transport of organic contaminants. This study investigates UV-based advanced oxidation processes (UV-AOPs) for treating DOM in ROC using a Parallel Factor Analysis (PARAFAC) approach. DOM composition and degradation were tested in UV-only and three UV-AOPs using hydrogen peroxide (H2O2), free chlorine (Cl2), and persulfate (S2O82-). The four-component PARAFAC model consisted of two terrestrial humic-like components (CUVH and CVisH), a wastewater/nutrient tracer component (CNuTr), and a protein-like (tyrosine-like) component (CPrTy). Based on the observed loss in the maximum fluorescence intensity of the components, DOM degradation was determined to be dependent on UV fluence, oxidant dose, and dilution factor of the ROC (i.e., bulk DOM concentration). CVisH was most the photolabile component in the UV-only system, followed by CNuTr, CPrTy, and CUVH, respectively. Furthermore, UV-H2O2 and UV-S2O82- displayed faster overall reaction kinetics compared to UV-Cl2. The degradation trends suggested that CNuTr and CPrTy consisted of chemical moieties that were susceptible to reactive oxygen species (HO•) but not reactive chlorine species; whereas, CVisH was sensitive to all reactive species generated in the three UV-AOPs. Compared to other components, CPrTy was recalcitrant in all treatment scenarios tested. Calculations using chemical probe-based analysis also confirmed these trends in the reactivity of DOM components. The outcomes of this study form a foundation for characterizing ROC reactivity in UV-AOP treatment technologies, to ultimately improve the sustainability of water reuse systems.


Assuntos
Água Potável , Poluentes Químicos da Água , Purificação da Água , Análise Fatorial , Peróxido de Hidrogênio , Osmose , Raios Ultravioleta , Águas Residuárias , Poluentes Químicos da Água/análise
15.
ACS Appl Mater Interfaces ; 13(34): 40590-40601, 2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-34415719

RESUMO

Two-dimensional single-atom catalysts (2D SACs) have been widely studied on the nitrogen reduction reaction (NRR). The characteristics of 2D catalysts imply that both sides of the monolayer can be catalytic sites and adsorb electrolyte ions or molecules from solutions. Overstrong adsorption of electrolyte ions or molecules on both sides of the catalyst site will poison the catalyst, while the adsorbate on one side of the catalytic site will modify the activity and selectivity of the other side for NRR. Discovering the influence of adsorption of electrolyte ions or molecules as a functional ligand on catalyst performance on the NRR is crucial to improve NRR efficiency. Here, we report this work using the density functional theory (DFT) method to investigate adsorption of electrolyte ions or molecules as a functional ligand. Among all of the studied 18 functional ligands and 3 transition metals (TMs), the results showed that Ru&F, Ru&COOH, and Mo&H2O combinations were screened as electrocatalysis systems with high activity and selectivity. Particularly, the Mo&H2O combination possesses the highest activity with a low ΔGMAX of 0.44 eV through the distal pathway. The superior catalytic performance of the Mo&H2O combination is mainly attributed to the electron donation from the metal d orbital. Furthermore, the functional ligands can occupy the active sites and block the competing vigorous hydrogen evolution reaction. Our findings offer an effective and practical strategy to design the combination of the catalyst and electrolyte to improve electrocatalytic NRR efficiency.

16.
Chemosphere ; 280: 130577, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33971408

RESUMO

In this study, the adsorption effect by freshly formed ferric hydroxide (FFFH) for the removal of 47 synthetic dye and antibiotic wastewaters under different pH conditions (i.e., pH = 4, 7, and 10) was investigated. The average total organic carbon (TOC) removal rates (Rexp) of pollutants under acidic, neutral, and alkaline conditions were 27.10 ± 3.21%, 15.16 ± 2.48%, and 9.72 ± 2.81%, respectively. By analyzing the characteristics of FFFH measured by SEM, XRD, FT-IR, TGA and BET, the properties of pollutants, and the values of Rexp, one can conclude that the large specific surface area and rich hydroxyl groups on the surface of FFFH were the reasons for its adsorption capacity for organic pollutants, and the electrostatic adsorption was the main reason for higher removal rate in acidic condition. Subsequently, to better elucidate the intrinsic factors influencing the removal rates at the molecular structure level, three optimal quantitative structure-activity relationship (QSAR) models were established by using multiple linear regression (MLR) analysis. Results of model validations (e.g., regression coefficient, internal and external verifications, and Y-randomization) showed that the established models exhibited excellent stability, reliability, and robustness with the values of R2 = 0.7544, 0.7764, 0.7528, Q2INT = 0.6451, 0.6836, 0.6228, and Q2EXT = 0.5890, 0.6029, 0.7298 under acidic, neutral, and alkaline conditions, respectively. The results of quantum parameter analysis revealed that the adsorption mechanism of FFFH for dyes and antibiotics mainly includes the activity of adsorption site, the behavior of electron transfer and the strength of molecular polarity.


Assuntos
Águas Residuárias , Poluentes Químicos da Água , Adsorção , Antibacterianos , Corantes , Compostos Férricos , Concentração de Íons de Hidrogênio , Cinética , Reprodutibilidade dos Testes , Espectroscopia de Infravermelho com Transformada de Fourier , Poluentes Químicos da Água/análise
17.
Phys Chem Chem Phys ; 23(7): 4178-4186, 2021 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-33586741

RESUMO

Designing atomically dispersed metal catalysts for the nitrogen reduction reaction (NRR) is an effective approach to achieve better energy conversion efficiencies. In this study, we designed a series of single molybdenum (Mo) atom-anchored porous two-dimensional Mo porphyrin (2D Mo-Pp) monolayers modified by B, C, O, P and S as efficient NRR catalysts to improve the catalytic performance. We introduced two key parameters, θ (pz orbital filling of heteroatoms) and φ (Bader charge of central Mo atoms). It shows that θ and φ play important roles in nitrogen absorption by analyzing the regression models. In particular, the theoretical results suggested that the 2D Mo-Pp monolayer modified by B has an ultralow limiting potential of 0.35 V and can suppress the hydrogen evolution reaction, making the 2D Mo-Pp monolayer modified by B a promising NRR electrocatalyst with high efficiency and selectivity. This work provides insights into the rational design of the elaborate structure of single-atom catalysts with tunable electrocatalytic activities.

18.
Environ Pollut ; 273: 116502, 2021 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-33486251

RESUMO

Based on the bond order, fukui indices and other related descriptors, as well as temperature, a new QSAR model was established to predict the rate constant (kO3) of VOCs degradation by O3. 302 logkO3 values (178-409 K) of 149 VOCs were divided into training set (242 logkO3) and test set (60 logkO3), respectively, which were used to construct and verify the QSAR model. The optimal model (R2 = 0.83, q2 = 0.82, Qext2 = 0.72) shows that EHOMO, BOx and q(C-)n have a greater influence on the value of logkO3. In addition, fukui indices and logkO3 are well correlated. The applicability domains of the current models can be used to predict kO3 of a wide range of VOCs at different temperatures.

19.
Environ Sci Pollut Res Int ; 28(6): 7191-7199, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33026623

RESUMO

Electrochemical reduction is a promising technology to treat polluted water contaminated by nitrate and nitrite ions under mild conditions. NO is an important intermediate species and determines selectivity toward different product and rate of whole reaction. However, the most studied NOER electrocatalysts are noble pure metal, which face problems of low utilization and high cost. Herein, by means of density functional theory computations, catalytic performance of 2D TM-Pc sheets (TM = Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Nb, Mo, Ru) as NOER catalysts were systematically evaluated. Among all the studied 2D TM-Pc sheets, our results revealed 2D Co-Pc sheet was identified as the best NOER catalyst, for a proper NO absorption energy and its relatively low limiting potential. The final reduction product of NOER is either NH3 at low coverages with energy input of 0.58 eV or N2O at high coverages with no energy barrier. Moreover, 2D Co-Pc sheet can efficiently suppress the competing HER. This study could not only provide a new approach for electrochemical denitrification to resolve environmental pollution but also be useful for valuable ammonia production.


Assuntos
Indóis , Óxido Nítrico , Catálise , Isoindóis , Oxirredução
20.
Aging (Albany NY) ; 12(9): 8680-8701, 2020 05 12.
Artigo em Inglês | MEDLINE | ID: mdl-32396871

RESUMO

Several of the thousands of long noncoding RNAs (lncRNAs) have been functionally characterized in various tumors. In this study, we aimed to explore the function and possible molecular mechanism of lncRNA KTN1 antisense RNA 1 (KTN1-AS1) involved in non-small cell lung cancer (NSCLC). We identified a novel NSCLC-related lncRNA, KTN1 antisense RNA 1 (KTN1-AS1) which was demonstrated to be distinctly highly expressed in NSCLC. KTN1-AS1 upregulation was induced by STAT1. Clinical study also suggested that higher levels of KTN1-AS1 were associated with advanced clinical progression and a shorter five-year overall survival. Functionally, loss-of-function assays with in vitro and in vivo experiments revealed that KTN1-AS1 promoted the proliferation, migration, invasion and EMT progress of NSCLC cells, and suppressed apoptosis. Mechanistic studies indicated that miR-23b was a direct target of KTN1-AS1, which functioned as a ceRNA to subsequently facilitate miR-23b's target gene DEPDC1 expression in NSCLC cells. Rescue experiments confirmed that KTN1-AS1 overexpression could increase the colony formation and migration ability suppressed by miR-23b upregulation in NSCLC cells. Overall, our findings imply that STAT1-induced upregulation of KTN1-AS1 display tumor-promotive roles in NSCLC progression via regulating miR-23b/DEPDC1 axis, suggesting that KTN1-AS1 may be a novel biomarker and therapeutic target for NSCLC patients.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/genética , Neoplasias Pulmonares/genética , Proteínas de Membrana/metabolismo , RNA Longo não Codificante/genética , Fator de Transcrição STAT1/metabolismo , Células A549 , Animais , Apoptose/genética , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Carcinoma Pulmonar de Células não Pequenas/patologia , Movimento Celular/genética , Proliferação de Células/genética , Progressão da Doença , Feminino , Proteínas Ativadoras de GTPase/genética , Proteínas Ativadoras de GTPase/metabolismo , Regulação Neoplásica da Expressão Gênica , Humanos , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patologia , Masculino , Proteínas de Membrana/genética , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , MicroRNAs/genética , MicroRNAs/metabolismo , Invasividade Neoplásica/genética , Proteínas de Neoplasias/genética , Proteínas de Neoplasias/metabolismo , Fator de Transcrição STAT1/genética , Regulação para Cima , Ensaios Antitumorais Modelo de Xenoenxerto
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