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1.
Sci Total Environ ; 754: 142336, 2021 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-33254905

RESUMO

The emergence of triclosan (TCS) in the environment has caused extensive concern, but its role in waste activated sludge (WAS) anaerobic fermentation (AF) is still uncertain. This work investigated the impact of TCS on volatile fatty acids (VFAs) recycling from WAS. The results showed that TCS of 200 mg/kg TSS increased the maximum VFA accumulation from 7284 to 15,083 mg COD/L. The increase in total VFA production is attributed to the massive increase in acetic acid. Mechanism exploration showed that TCS promotes WAS solubilization by facilitating cell breakage and extracellular polymeric substances disruption, and stimulates AF by enhancing the activity of key enzymes among all stages. TCS promotes acidification stronger than methanogenesis, which makes VFA production faster than consumption, leading to increased VFA accumulation. These findings provide novel insights for revealing the role of TCS in WAS resource recovery, and offer thoughts for the selective production of final recycling products of TCS-containing WAS.

2.
J Hazard Mater ; 402: 123498, 2021 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-32712366

RESUMO

N-doped nanoporous carbon (NC) with two-dimensional structure derived from Zn-ZIF-L via KCl exfoliation and carbonization at different temperature were prepared for adsorptive removal of tetracycline (TC). Characterizations revealed the effective dopant of N atoms and low degree of graphitization with more defects related to the enhanced adsorption capacity of the NC materials. Benefiting from the huge surface area (2195.57 m2 g-1), high porosity (1.34 cm3 g-1) and accessible sheeting structure, the NC-800 exhibited its fast and efficient adsorption of TC in 60 min. Meantime, the maximum adsorption of TC could reach 347.06 mg g-1. Effects of pH, humic acid (HA) and ionic strength (Na+, Ca2+) were studied along with the interactions among influencing factors investigated by response surface model (RSM). By optimizing experimental conditions from RSM, the adsorption capacity could increase to 427.41 mg g-1. Additionally, electrostatic interaction and hydrogen bond interaction might play a dominating role in adsorption reaction. The NC-800 could maintain a high adsorption level after four cycles. Therefore, the NC-800 with great adsorptive property and reusability could be considered as an effective adsorbent with promising potential in applications for water treatment.

3.
J Colloid Interface Sci ; 581(Pt A): 195-204, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-32771731

RESUMO

Compared with the transition metal induced homogeneous catalytic system, the heterogeneous catalytic system based on transition metal-doped metal organic frameworks (MOFs) were stable for the efficient utilization of transition metal and avoiding the metal leaching. The aim of this work is to synthesize Co-doped MIL-53(Al) by one-step solvent thermal method and use it to activate peroxymonosulfate (PMS) to remove tetracycline (TC) in water. The successful synthesis of Co-MIL-53(Al) samples was demonstrated by XDR, SEM and FTIR characterizations. The 25% Co-MIL-53(Al)/PMS system showed the optimal TC removal effect compared to the PMS alone and MIL-53(Al)/PMS system. The catalytic performances of Co-MIL-53(Al)/PMS system in conditions of different pH, co-existing substances and water bodies were investigated. Quenching experiment and electron paramagnetic resonance (EPR) showed that the degradation mechanism by Co-MIL-53(Al) activation PMS was mainly attributed to sulfate radical (SO4•-) and singlet oxygen (1O2) non-radical. The degradation intermediates of TC were also identified and the possible degradation pathways were proposed. Co-MIL-53(Al) showed good activity after four cycles. These findings demonstrated that Co-MIL-53(Al) can be a promising heterogeneous catalyst for activating PMS to degrade TC.

4.
J Colloid Interface Sci ; 580: 470-479, 2020 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-32711198

RESUMO

Herein, Mn-doped MIL-53(Fe) were fabricated via one-pot solvothermal method and used for peroxymonosulfate (PMS) activation towards tetracycline (TC) degradation from aqueous solution. The characterizations of SEM, FTIR and XRD were utilized to reveal the morphology and structure of the materials. The results showed that Mn-MIL-53(Fe)-0.3 displayed the optimal catalytic performance, the removal efficiency of TC could reach 93.2%. Moreover, the catalytic activity of Mn-MIL-53(Fe) towards TC under different initial pH values, co-existing anions (Cl-,CO32- and SO42-) and humic acid (HA) were investigated. The results of thermodynamic experiment suggested that the catalytic process was endothermic. In addition, integrated with capture experiments results and the characterization results of electron paramagnetic resonance (EPR), which revealed that SO4·- and HO- were the reactive radicals involving in the reaction. More importantly, the possible activation mechanism was discussed in detail based on the X-ray photoelectron spectroscopy results. The active species were generated by the active sites of Fe(II) and Mn(II) on Mn-MIL-53(Fe) effectively activated PMS. Furthermore, the degradation intermediates and possible degradation pathway were investigated by LC-MS. Finally, the catalyst also showed good performance in actual wastewater and demonstrated good recyclability. The Mn-MIL-53(Fe)/PMS system exhibited a promising application prospect for antibiotic-containing waste water treatment.

5.
Water Res ; 184: 116200, 2020 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-32712506

RESUMO

Advanced oxidation processes (AOPs) have attracted much interest in the field of water treatment owing to their high removal efficiency for refractory organic contaminants. Graphitic carbon nitride (g-C3N4)-based catalysts with high performance and cost effectiveness are promising heterogeneous catalysts for AOPs. Most research on g-C3N4-based catalysts focuses on photocatalytic oxidation, but increasingly researchers are paying attention to the application of g-C3N4-based catalysts in other AOPs beyond photocatalysis. This review aims to concisely highlight recent state-of-the-art progress of g-C3N4-based catalysts in AOPs beyond photocatalysis. Emphasis is made on the application of g-C3N4-based catalysts in three classical AOPs including Fenton-based processes, catalytic ozonation and persulfates activation. The catalytic performance and involved mechanism of g-C3N4-based catalysts in these AOPs are discussed in detail. Meanwhile, the effect of water chemistry including pH, water temperature, natural organic matter, inorganic anions and dissolved oxygen on the catalytic performance of g-C3N4-based catalysts are summarized. Moreover, the reusability, stability and toxicity of g-C3N4-based catalysts in water treatment are also mentioned. Lastly, perspectives on the major challenges and opportunities of g-C3N4-based catalysts in these AOPs are proposed for better developments in the future research.


Assuntos
Grafite , Água , Catálise , Compostos de Nitrogênio
6.
Sci Rep ; 10(1): 9856, 2020 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-32528058

RESUMO

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

7.
Small ; 16(29): e2001634, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32567191

RESUMO

Semiconductor photocatalysis is a promising technology to tackle refractory antibiotics contamination in water. Herein, a facile in situ growth strategy is developed to implant single-atom cobalt in polymeric carbon nitride (pCN) via the bidentate ligand for efficient photocatalytic degradation of oxytetracycline (OTC). The atomic characterizations indicate that single-atom cobalt is successfully anchored on pCN by covalently forming the CoO bond and CoN bond, which will strengthen the interaction between single-atom cobalt and pCN. This single-atom cobalt can efficiently expand optical absorption, increase electron density, facilitate charge separation and transfer, and promote OTC degradation. As the optimal sample, Co(1.28%)pCN presents an outstanding apparent rate constant for OTC degradation (0.038 min-1 ) under visible light irradiation, which is about 3.7 times than that of the pristine pCN. The electron spin resonance (ESR) tests and reactive species trapping experiments demonstrate that the 1 O2 , h+ , •O2 - , and •OH are responsible for OTC degradation. This work develops a new way to construct single-atom-modified pCN and provides a green and highly efficient strategy for refractory antibiotics removal.

8.
J Hazard Mater ; 398: 122957, 2020 11 05.
Artigo em Inglês | MEDLINE | ID: mdl-32474321

RESUMO

The development of carbon materials brings a new two-dimensional catalyst support, graphdiyne (GDY), which is attracting increasing interest in the field of catalysis. This article presents a systematical review of recent studies about the characteristics, design strategies, and applications of GDY-supported catalysts. The sp- and sp2-hybridized carbon, high electrical conductivity, direct band gap, and high intrinsic carrier mobility are key characteristics for GDY to serve as a competitive catalyst support. Hydrothermal method (or solvothermal method), GDY in-situ growth, and electrochemical deposition are commonly used to load catalysts on GDY support. In the applications of GDY-supported photocatalysts, GDY mainly serves as an electron or hole transfer material. For the electrocatalytic hydrogen production, the unique electronic structure and high electrical conductivity of GDY can promote the electron transfer and water splitting kinetics. This review is expected to provide meaningful insight and guidance for the design of GDY-supported catalysts and their applications.

9.
Sci Total Environ ; 724: 138248, 2020 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-32247117

RESUMO

In this work, we investigated the impact of iron nanoparticle, including magnetite nanoparticles (Fe3O4 NPs) and nanoscale zero-valent iron (nZVI), on the anaerobic digestion (AD) performance. Moreover, the evolutions of antibiotic resistance genes (ARGs), class 1 integrons-integrase (intI1) and potential hosts of ARGs were also investigated. The optimal addition of Fe3O4 NPs and nZVI to promote methane production was 0.5 g/L and 1 g/L, which led to 22.07% and 23.02% increase in methane yield, respectively. The degradation rate of organic matter was also enhanced with the addition of Fe3O4 NPs or nZVI. The results of high-throughput sequencing showed that the reactors with iron NPs exhibited significant differences in microbial community structure, compared to the reactors with the non­iron NPs. Iron NPs have caused the relative abundance of the dominant bacteria (Proteobacteria, Firmicutes and Actinobacteria) generally decreased, while the dominant archaea (Euryarchaeota) increased in AD sludge. Quantitative PCR results revealed that iron NPs accelerated the reductions in total absolute abundance of ARGs, especially a beta-lactamase resistance encoded gene (blaOXA). Network analysis displayed that the attenuation of ARGs was mainly attributed to the decline of potential hosts (Proteobacteria, Firmicutes and Actinobacteria). Meanwhile, environmental factors (such as pH, soluble chemical oxygen demand and heavy metals) were also strongly correlated with ARGs.


Assuntos
Integrons , Nanopartículas , Anaerobiose , Antibacterianos/farmacologia , Resistência Microbiana a Medicamentos/efeitos dos fármacos , Genes Bacterianos/efeitos dos fármacos , Integrases/farmacologia , Ferro/farmacologia , Esgotos
10.
Bioresour Technol ; 304: 123016, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32078907

RESUMO

The effects of four conductive nanomaterials (nano-carbon powder, nano-Al2O3, nano-ZnO, nano-CuO) on sludge anaerobic digestion (AD) performance and microbial community were investigated through a 36-day fermentation experiment. Results showed that biogas production enhanced by 16.9% and 23.4% with nano-carbon powder and nano-Al2O3 added but decreased by 90.2% and 17.3% with nano-ZnO and nano-CuO. Total solids (TS) removal efficiency was increased by 38.73% and 27.11% with nano-carbon powder and nano-Al2O3 added but decreased by 70.67% and 43.70% with nano-ZnO and nano-CuO. Kinetic analysis indicated four conductive nanomaterials could shorten the lag phase of AD sludge with an average rate of 51.75%. 16S rRNA amplicon sequencing results demonstrated microbes such as Syntrophomonas and Methanosaeta were enriched in nano-carbon powder and nano-Al2O3 reactors. However, microbial community diversity and richness were both inhibited by adding nano-ZnO and nano-CuO. Redundancy analysis (RDA) revealed that genera belong to Firmicutes and Chloroflexi could conduce to methanogenesis process.


Assuntos
Microbiota , Nanoestruturas , Anaerobiose , Reatores Biológicos , Cinética , Metano , RNA Ribossômico 16S , Esgotos
11.
J Colloid Interface Sci ; 561: 501-511, 2020 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-31735413

RESUMO

A novel yolk-shell Ag3PO4@MIL-53(Fe) Z-scheme photocatalyst was fabricated via a "bottle-around-ship" like method. Experiments on the treatment of tetracycline upon visible light irradiation showed that the as-prepared photocatalyst possessed excellent photocatalytic performance. Experimental results showed that tetracycline removal efficiency of the yolk-shell Ag3PO4@MIL-53(Fe) Z-scheme photocatalyst was almost 3 times higher than that of MIL-53(Fe). The enhanced photocatalytic performance of Ag3PO4@MIL-53(Fe) nanocomposite could be contributed to its higher surface area, better absorption capability, and greater charge separation efficiency. In addition, the H2O2 concentration detection results for Ag3PO4 (154 µmol/L) and Ag3PO4@MIL-53(Fe) (52 µmol/L) indicated that a big part of generated H2O2 on the Ag3PO4 core would be quickly decomposed by the MIL-53(Fe) shell and generated more reactive species through the photo-Fenton-like reaction, which is beneficial for the improvement of photocatalytic performance. This is a promising approach to fabricate yolk-shell structure photocatalyst and a different aspect to design multiple semiconductor composites heterojunction for environmental remediation.

12.
J Hazard Mater ; 386: 121947, 2020 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-31884358

RESUMO

Polymeric carbon nitride (PCN) has become the most promising metal-free photocatalysts but its activity is low. Molecule doping of PCN has been proved to be an effective strategy to achieve high photocatalytic performance. Herein, we report a bottom-up method to synthesize modified PCN, which includes 2,5-dibromopyrazine doping, thermal-induced exfoliation and condensation/polymerization. The incorporation of electron-deficiency 2,5-dibromopyrazine into the PCN framework can effectively tune the electronic structures and improve the charge-carrier separation. In addition, the incorporation of 2,5-dibromopyrazine induced significant structural changes from planar symmetric to distortion. The optimized pyrazine doped PCN showed a reaction rate enhancement of 4-fold for the degradation of sulfamethazine compared to that of conventional urea-based PCN. Further reactive species and degradation intermediate detection studies, indicated that O2- was generated during the photocatalytic process, which could lead to the decomposition, and finally mineralization of sulfamethazine. 2,5-Dibromopyrazine doped PCN also leads to a 6.3-fold improvement in H2 generation with the visible light. Especially, phytotoxicity experiments showed that the toxicity of sulfamethazine after degradation is greatly reduced, and the as-prepared photocatalyst is environmentally friendly.

13.
Bioresour Technol ; 294: 122139, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31525586

RESUMO

The effect of nanoscale zero-valent iron (NZVI) and magnetite nanoparticles (Fe3O4 NPs) on anaerobic digestion (AD) performance was investigated through a series of 100-day semi-continuous mesophilic anaerobic digestions. The results indicated that biogas production had increased by 24.44% and 21.66% with the addition of 0.5 g/L Fe3O4 NPs and 1.0 g/L NZVI, respectively. Besides, the abundance of five widespread antibiotic resistance genes (ARGs) (ermF, ermA, ermT, aac(6')-IB, blaOXA-1) was also studied. The decrease in abundance of aac(6')-IB and blaOXA-1 was observed during the AD process with an average removal rate of 95.69% and 44.82%, respectively. Most of the ARGs, especially ermA and ermT, were less abundant in NZVI group compared with control group. The overall results suggested that the addition of NZVI and Fe3O4 NPs contributed to a better sludge anaerobic digestion performance, and NZVI was beneficial to the removal of some ARGs.


Assuntos
Nanopartículas de Magnetita , Nanopartículas , Aminoglicosídeos , Anaerobiose , Ferro , Macrolídeos , Resistência beta-Lactâmica
14.
J Hazard Mater ; 380: 120815, 2019 12 15.
Artigo em Inglês | MEDLINE | ID: mdl-31295684

RESUMO

Polymeric carbon nitride semiconductor has been explored as emerging metal-free photocatalyst for solving the energy shortage and environmental issues. However, the efficiency of carbon nitride is still not satisfying. Herein, a facile copolymerization between L-cysteine and dicyandiamide has been applied to forming the modified carbon nitride photocatalysts. The photocatalytic performance was evaluated through degrading sulfamethazine under visible light illumination. The ameliorative structure and tuned energy band result in visible-light adsorption enhancement. In addition, nitrogen vacancies offer more sites to adsorbing molecular oxygen, thereby facilitating the transfer of electrons from carbon nitride to the surface adsorbed oxygen. As a result, the degradation rate of optimized modified carbon nitride sample for sulfamethazine was 0.1062 min-1, which was almost 12 times than that of carbon nitride (0.0086 min-1). Superoxide radicals and holes were mainly responsible for the sulfamethazine photodegradation by modified carbon nitride. Two reaction intermediates/products were observed and identified by high performance liquid chromatography-mass spectrometer, and a possible reaction pathway was proposed. This study provides new insights into the design of highly efficient photocatalyst for other organic pollutants degradation.

15.
Chemosphere ; 236: 124387, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31336240

RESUMO

The treatment of wastewater containing hydrophobic organic pollutants solubilized by surfactants is of great environmental importance. In this work, the removal of rhamnolipid-solubilized hexadecane via a salicylic acid-methanol-acetone modified steel converter slag (SMA-SCS) catalyzed Fenton-like process was studied. First, we investigated the adsorption of rhamnolipid and hexadecane onto SCS and SMA-modified SCS. Compared to that of SCS, SMA-SCS exhibited better adsorption performance with maximum adsorption capacities of 0.23 and 0.28 mg/g for hexadecane and rhamnolipid, respectively. Degradation experiments showed that hexadecane was more readily degraded by the Fenton-like process than rhamnolipid. Up to 81.1% of hexadecane removal was achieved over 20 g/L of SMA-SCS within 24 h, whereas only 36% of rhamnolipid was degraded. On the other hand, the results indicated that increased rhamnolipid concentration had a negative effect on the degradation of hexadecane. During the oxidation reaction, the pH value of solution remained between 6.0 and 6.72. All these results demonstrated that the SMA-SCS/H2O2 Fenton-like process could be a cost-effective and promising approach for the treatment of surfactant-solubilized hydrophobic organic compounds.


Assuntos
Alcanos/química , Glicolipídeos/química , Águas Residuárias/química , Catálise
16.
Chemosphere ; 232: 186-194, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31154179

RESUMO

This study proposes a facile one-pot solvothermal method to prepare Ni-doped MIL-53(Fe) nanoparticles as high-performance adsorbents for doxycycline removal. The morphology and structure of the samples were characterized by scanning electron microscopy, transmission electron microscopy, X-ray diffraction, X-ray photoelectron spectroscopy, fourier transform infrared spectrum and thermogravimetric analysis. These results reveal that nickel was doped into MIL-53(Fe) successfully via a facile reaction, and the obtained Ni-doped MIL-53(Fe) nanoparticles showed excellent stability. The adsorption activities were evaluated in terms of the removal efficiencies of doxycycline (DOX) in aqueous solution. According to the response surface quadratic model (RSM), the optimal adsorption conditions were concentration of DOX 100 mg/L, temperature 35 °C, ionic strength 5 g/L and pH 7. The as-synthesized Ni-doped MIL-53(Fe) nanoparticles showed better adsorption capacity of 397.22 mg/g compared with other adsorbents. The investigation of adsorption mechanism demonstrated that the adsorption process was dominated by electrostatic and π-π stacking interactions. The Ni-doped MIL-53(Fe) nanoparticles with improved adsorption activities would have a great potential in DOX removal from aqueous environment.


Assuntos
Doxiciclina/química , Poluentes Químicos da Água/química , Purificação da Água/métodos , Adsorção , Doxiciclina/análise , Dietilamida do Ácido Lisérgico/análogos & derivados , Microscopia Eletrônica de Varredura , Microscopia Eletrônica de Transmissão , Nanopartículas/química , Níquel , Concentração Osmolar , Espectroscopia de Infravermelho com Transformada de Fourier , Temperatura , Água , Poluentes Químicos da Água/análise , Difração de Raios X
17.
Sci Total Environ ; 683: 124-133, 2019 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-31129323

RESUMO

As the functional material, iron nanoparticles effectively promote anaerobic digestion (AD) process, including the hydrolysis-acidification process and the biogas production. In this study, nano zero-valent iron (nZVI) and Fe3O4 nanoparticles (Fe3O4 NPs) were added to AD reactors respectively. The AD process was evaluated by the reactors performances, including pH, biogas yields and compositions, as well as the removal ratio of total solids (TS), volatile solids (VS) and soluble chemical oxygen demand (sCOD). Three models (first-order kinetic model, transfer function model and Cone model) were used to explore the kinetics of AD biogas production. The results showed that adding appropriate dose of nZVI or Fe3O4 NPs enhanced anaerobic digestibility of sludge. The highest cumulative biogas yield of 140.34 L with 0.5 g L-1 nZVI and 137.13 L with 1 g L-1 Fe3O4 NPs were obtained by the 80 days of mesophilic operation, respectively. Cumulative biogas productions of these two reactors were significantly enhanced up to 15.70% and 13.44%. TS removal rates reached >70% in all AD reactors with iron nanoparticles, and the highest sCOD removal rates of nZVI and Fe3O4 NPs digesters on the 80th day were 88.22% and 77.63%, respectively. The results of the three-day fermentation experiment and the kinetic parameters showed that the nZVI or Fe3O4 NPs enhanced the hydrolysis-acidification process of the AD, which eventually promoted biogas production. The Cone model was satisfied with the experimental results, which could be used to evaluate the kinetics of AD with iron nanoparticles more reasonably.


Assuntos
Biocombustíveis/análise , Óxido Ferroso-Férrico/química , Ferro/química , Nanopartículas Metálicas/química , Esgotos/química , Anaerobiose , Reatores Biológicos , Cinética
18.
Bioresour Technol ; 282: 179-188, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30861447

RESUMO

Continuous stirred-tank digesters with tetracyclines and sulfonamides were operated to investigate the impacts of antibiotic pressure on sludge anaerobic digestion. The versatile methanogen Methanosarcinales and strictly hydrogenotrophic methanogen Methanobacteriales increased and decreased by 21.1% and 10.9% under antibiotic pressure, respectively. KEGG analysis revealed that hydrogenotrophic and acetoclastic methanogenesis pathways were all affected. The decrease in abundance of function genes involved in lipid metabolism, carbohydrate metabolism, and fatty acid degradation, would lead to a reduction in methane production by 25%. Network analysis indicated positive associations among tetracycline residuals, abundance of resistance genes (ARGs), and specific member of potential hosts. Over 1000 ARG subtypes were widely detected in sludge, including macrolide (28%), tetracycline (24%), fluoroquinolone (20%), and peptide (20%) resistance genes. AD process exposed to long-term antibiotic would increase the diversity and abundance of ARG, enhance the association of ARG with specific microbes, and select bacteria able to perform chemotaxis mechanism.


Assuntos
Antibacterianos/farmacologia , Metagenômica , Esgotos/microbiologia , Tetraciclina/farmacologia , Anaerobiose , Farmacorresistência Bacteriana/efeitos dos fármacos , Methanosarcinales/efeitos dos fármacos , Fatores de Risco
19.
Chemosphere ; 222: 184-194, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30708152

RESUMO

Adsorption behaviors and mechanisms of metal endocrine disruptors (Pb2+, Cd2+, and Hg2+) by pyrogenic carbonaceous materials including engineered carbons (biochar and activated carbon) and carbon nanomaterials (multi-walled carbon nanotubes and graphene oxide) have been investigated by experimental and density functional theory (DFT) studies. The adsorption isotherms of metal endocrine disruptors on carbonaceous materials were better fitted by Langmuir models. The adsorption capacities were in the order as follows: GO > BC600 > BC300 > CNT > AC for Pb2+, GO > BC300 > AC > BC600 > CNT for Cd2+, and GO > BC300 ≥ AC > CNT > BC600 for Hg2+, respectively. The DFT-computed binding energy (kcal/mol) of different oxygen-containing functional groups with metal endocrine disruptors followed the orders: (ⅰ) CMCOCPb (-136.70) > CM-COO--Pb (-91.58) > CMCOPb (-33.57) > CMOHPb (-4.69), (ⅱ) CM-COO--Cd (-45.91) > CMCOCCd (-4.49) > CMOHCd (-3.68) > CMCOCd (1.08), (ⅲ) CM-COO--Hg (-25.51) > CMCOCHg (-3.58) > CMOHHg (-0.63) > CMCOHg (0.23). And COC has the highest binding energy for Pb2+, whereas COC has much lower binding energy for Cd2+ and Hg2+. Comprehensively considering DFT calculations, competitive adsorption results and the cost analysis, this work may provide insights into the design of selective adsorbent for specific contaminant.


Assuntos
Adsorção , Carvão Vegetal/química , Disruptores Endócrinos/química , Nanotubos de Carbono/química , Teoria da Densidade Funcional , Metais/toxicidade , Nanoestruturas , Poluentes Químicos da Água/química
20.
BMC Nephrol ; 20(1): 41, 2019 02 06.
Artigo em Inglês | MEDLINE | ID: mdl-30727972

RESUMO

BACKGROUND: Cystatin C (Cys C) used clinically for detecting early acute kidney injury (AKI) was reported to be associated with thyroid function. Therefore, whether the performance of Cys C is affected by thyroid hormones has raised concern in critically ill patients. This study aimed to investigate the impact of thyroid hormones on the diagnostic and predictive accuracy of Cys C for AKI, and hence optimize the clinical application of Cys C. METHODS: A prospective observational study was conducted in the general intensive care units (ICUs). Serum creatinine (SCr), Cys C, and thyroid function were documented for all patients at ICU admission. Patients were separated into five quintiles based on free triiodothyronine (FT3) and total triiodothyronine (TT3), and two categories according to the presence of low T3 syndrome or not. The impact of thyroid function on the performance of Cys C in diagnosing and predicting AKI was assessed by area under the receiver operating characteristic curve (AUC). RESULTS: The AKI incidence was 30.0% (402/1339); 225 patients had AKI upon entry, and 177 patients developed AKI during the subsequent 7 days. The AUCs for Cys C in detecting total AKI, established AKI, and later-onset AKI was 0.753, 0.797, and 0.669, respectively. The multiple linear regression analysis demonstrated that TT3 and FT3 were independently associated with Cys C. Overall, although Cys C did not yield any significant difference in AUCs for detecting AKI among patients with different thyroid hormones, the optimal cut-off value of Cys C to detect AKI was markedly different between patients with and without low T3 syndrome. CONCLUSIONS: The thyroid function had no significant impact on the diagnostic and predictive accuracy of Cys C in detecting AKI in ICU patients. However, the optimal cut-off value of Cys C to detect AKI could be affected by thyroid function.


Assuntos
Lesão Renal Aguda/sangue , Cistatina C/sangue , Glândula Tireoide/fisiopatologia , Tri-Iodotironina/sangue , APACHE , Lesão Renal Aguda/complicações , Lesão Renal Aguda/diagnóstico , Lesão Renal Aguda/fisiopatologia , Adulto , Área Sob a Curva , Creatinina/sangue , Estado Terminal , Diagnóstico Precoce , Feminino , Humanos , Hipotireoidismo/sangue , Hipotireoidismo/complicações , Hipotireoidismo/fisiopatologia , Tempo de Internação/estatística & dados numéricos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Estudos Prospectivos , Curva ROC , Tiroxina/sangue
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