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1.
Clin Anat ; 2024 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-38725353

RESUMO

Cadaveric study; To describe the characteristics of the nerve and its relationship with the lumbar intervertebral disc and psoas major muscle. Nerve injury is an understudied complication of extreme lateral interbody fusion. A detailed description of the nerve anatomy would be helpful for surgeons to minimize the risk of this complication. The lumbar plexus and lumbar sympathetic nerve of 10 embalmed male cadavers were dissected, and the distribution, number, and spatial orientation of the nerves on the L1/2 to L4/5 intervertebral discs were examined. Metal wires were applied along nerve paths through the psoas major muscle. The position of the nerves was examined on CT. In zone III at L1/2 and L4/5, no nerves were found. In zone II and zone III at L2/3, no lumbar plexus was found, and only the ramus communicans passed through. At the L1-L5 level, the density of nerves in the posterior half of the psoas major muscle was greater than that in the anterior half. The lumbar plexus was found in all of zone IV. The genitofemoral nerve emerges superficially and anteriorly from the medial border of the psoas major at the L3-4 level, but at the L1/2 level, the sympathetic trunk is located in zone II. The remaining disc-level sympathetic trunks appear in zone I. No nerves were found in zone III of the L1/2 or L4/5 disc. In zones II and III of L2/3, the lumbar plexus appears safe. The genitofemoral nerve travels through zones II and III of L3/4. The distribution density of nerves in the posterior half of the psoas major muscle was greater than that in the anterior half of that muscle at the L1-L5 level.

2.
J Hazard Mater ; 460: 132400, 2023 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-37639789

RESUMO

Over the past few years, advanced oxidation processes (AOPs) have shown promising efficiencies for wastewater remediation. Carbocatalysis, in particular, has been exploited widely thanks to its sustainable and economical properties but has an issue of recovery and reusability of the catalysts. To address this, three-dimensional (3D) binary and ternary graphene-based composites in the form of macro discs were created to activate peroxymonosulfate (PMS) for catalytic oxidation of sulfamethoxazole (SMX). Graphene oxide served as the base, while graphitic carbon nitride (g-C3N4) and/or single-walled carbon nanotubes (SWCNTs) were added. Among the various discs synthesized, rGNTCN discs (ternary composite) were proven to be the most efficient by completely degrading SMX in 60 min owing to their large surface area and nitrogen loading. The catalytic system was further optimized by varying the reaction parameters, and selective radical quenching and electron paramagnetic resonance tests were performed to identify the active radical, revealing the synergistic role of both radical and non-radical pathways. This led to the development of possible SMX degradation pathways. This research not only provides insights into ternary carbocatalysis but also gives a novel breakthrough in catalyst recovery and reusability by transforming nanocatalysts into macro catalysts.

3.
Small Methods ; 7(10): e2300588, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37415309

RESUMO

Industrial and disinfection wastewater typically contains high levels of organic pollutants and residue hydrogen peroxide, which have caused environmental concerns. In this work, dual-asymmetric MnO2 @polymer microreactors are synthesized via pollutant polymerization for self-driven and controlled H2 O2 decomposition. A hollow and asymmetric MnO2 nanotube is derived from MnO2 nanorods by selective acid etching and then coated by a polymeric layer from an aqueous phenolic pollutant via catalytic peroxymonosulfate (PMS)-induced polymerization. The evolution of particle-like polymers is controlled by solution pH, molar ratios of PMS/phenol, and reaction duration. The polymer-covered MnO2 tubing-structured micromotors presented a controlled motion velocity, due to the reverse torque driven by the O2 bubbles from H2 O2 decomposition in the inner tunnels. In addition, the partially coated polymeric layer can regulate the exposure and population of Mn active sites to control the H2 O2 decomposition rate, thus avoiding violent motions and massive heat caused by vigorous H2 O2 decomposition. The microreactors can maintain the function of mobility in an ultra-low H2 O2 environment (<0.31 wt.%). This work provides a new strategy for the transformation of micropollutants to functional polymer-based microreactors for safe and controlled hydrogen peroxide decomposition for environmental remediation.

4.
Small ; 19(23): e2207666, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36703516

RESUMO

H2 O2 -fueled micromotors are state-of-the-art mobile microreactors in environmental remediation. In this work, a magnetic FeOx @MnO2 @SiO2 micromotor with multi-functions is designed and demonstrated its catalytic performance in H2 O2 /peroxymonosulfate (PMS) activation for simultaneously sustained motion and organic degradation. Moreover, this work reveals the correlations between catalytic efficiency and motion behavior/mechanism. The inner magnetic FeOx nanoellipsoids primarily trigger radical species (• OH and O2 •- ) to attack organics via Fenton-like reactions. The coated MnO2 layers on FeOx surface are responsible for decomposing H2 O2 into O2 bubbles to provide a propelling torque in the solution and generating SO4 •- and • OH for organic degradation. The outer SiO2 microcapsules with a hollow head and tail result in an asymmetrical Janus structure for the motion, driven by O2 bubbles ejecting from the inner cavity via the opening tail. Intriguingly, PMS adjusts the local environment to control over-violent O2 formation from H2 O2 decomposition by occupying the Mn sites via inter-sphere interactions and enhances organic removal due to the strengthened contacts and Fenton-like reactions between inner FeOx and peroxides within the microreactor. The findings will advance the design of functional micromotors and the knowledge of micromotor-based remediation with controlled motion and high-efficiency oxidation using multiple peroxides.

5.
J Hazard Mater ; 448: 130874, 2023 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-36716559

RESUMO

Membrane separation and sulfate radicals-based advanced oxidation processes (SR-AOPs) can be combined as an efficient technique for the elimination of organic pollutants. The immobilization of metal oxide catalysts on ceramic membranes can enrich the membrane separation technology with catalytic oxidation avoiding recovering suspended catalysts. Herein, nanostructured Co3O4 ceramic catalytic membranes with different Co loadings were fabricated via a simple ball-milling and calcination process. Uniform distribution of Co3O4 nanoparticles in the membrane provided sufficient active sites for catalytic oxidation of 4-hydroxybenzoic acid (HBA). Mechanistic studies were conducted to determine the reactive radicals and showed that both SO4•- and •OH were present in the catalytic process while SO4•- plays the dominant role. The anti-fouling performance of the composite Co@Al2O3 membranes was also evaluated, showing that a great flux recovery was achieved with the addition of PMS for the fouling caused by humic acid (HA).

6.
J Colloid Interface Sci ; 634: 972-982, 2023 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-36571859

RESUMO

Photo-Fenton-like catalysis allows development of novel advanced oxidation technology with promising application in wastewater treatment. In this work, carbon dots (CDs) were intercalated between CuO nanoparticles and coralloid flower-like graphitic carbon nitride (g-C3N4) to fabricate a ternary CuO/CDs/g-C3N4 hybrid for synergetic visible-light-driven photo-Fenton-like oxidation. The CuO/CDs/g-C3N4 hybrid showed remarkable degradation efficiency towards recalcitrant organic contamination, excellent tolerance to realistic environmental conditions, exceptional stability and wide universality, declaring great potential for practical applications. •OH and •O2- radicals were demonstrated to be the primary contributors in the photo-Fenton-like system. Mechanism studies reveal dual charge transfer pathways in the Z-scheme CuO/g-C3N4 heterojunction assisted by interfacial electron transmission bridges of CDs, which can simultaneously boost the reduction of Cu2+ to Cu+ in the Fenton-like cycle and accelerate the Z-scheme electron flow from CuO to g-C3N4, leading to synergistic enhancement of the catalytic performance. This work would afford a feasible strategy to develop reinforced solar energy-assisted photo-Fenton-like catalysis systems for water remediation.

7.
J Colloid Interface Sci ; 632(Pt A): 117-128, 2023 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-36410293

RESUMO

Increasing water pollution has imposed great threats to public health, and made efficient monitoring and remediation technologies critical to a clean environment. In this study, a versatile heterojunction of Au nanoparticles modified phosphorus doped carbon nitride (Au/P-CN) is designed and fabricated. The Au/P-CN heterostructure demonstrates improved light absorption, rapid separation of charge carriers, and improved electrical conductivity. Taking the toxic 4-chlorophenol (4-CP) as an example, an ultrasensitive photoelectrochemical (PEC) sensor is successfully demonstrated, exhibiting a wide linear range (0.1-52.1 µM), low detection limit (∼0.02 µM), significant stability and selectivity, as well as reliable analysis in real samples. Moreover, efficient photocatalytic degradation with a high removing efficiency (∼87%) toward 4-CP is also achieved, outperforming its counterpart of Au nanoparticles (NPs) modified graphitic carbon nitride (Au/g-CN, ∼59%). This work paves a new way for efficient and simultaneous detection and remediation of organic pollutants over versatile photoactive catalysts.


Assuntos
Ouro , Nanopartículas Metálicas , Fósforo
8.
Cir Cir ; 90(5): 632-637, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36327468

RESUMO

OBJECTIVE: The objective of this study was to investigate the role of sirtuin 6 (SIRT6) in severe community acquired pneumonia (CAP) in child patients. METHODS: This prospective observational research enrolled a total of 75 severe child CAP patients who went to our hospital during April 2016 to December 2020, and 75 mild/moderate CAP child patients were included as control. SIRT6 and inflammatory factors C-reactive protein (CRP), interleukin (IL)-6, and procalcitonin (PCT) were tested by the enzyme linked immunosorbent assay (ELISA). Demographic data including age, sex, as well as clinical symptoms, duration of ICU stay, duration of mechanical ventilation were collected. The routine blood test was conducted for all patients and WBC amount and neutrophil ratio were recorded. The pediatric critical illness score (PCIS) and 1-month mortality were collected. RESULTS: Levels of SIRT6 were remarkably lower in severe CAP patients or deceased patients compared with mild/moderate or survival patients, respectively. Levels of CRP, PCT, and interleukin-6 (IL-6) were markedly higher in severe patients than mild/moderate patients. However, only levels of CRP were significantly higher in deceased CAP patients and serum levels of SIRT6 were negatively correlated with serum levels of CRP, PCT, and IL-6. The higher levels of CRP, PCT and IL-6, as well as higher mortality rate and lower levels of PCIS were found in patients with lower SIRT6 compared with parents with higher SIRT6. SIRT6 had the potential for diagnosis of severe CAP and patients with lower SIRT1 showed shorter 1-month survival. Further, logistic regression showed that only age and CRP were independent risk factors for 1-month mortality of CAP child parents. CONCLUSION: Down-regulated SIRT6 in severe CAP child patients predicted higher expression of inflammatory factors, severer clinical outcomes and poor prognosis.


OBJETIVO: Investigar el papel de sirtuin 6 (SIRT6) en la neumonía adquirida en la comunidad (NAC) grave en pacientes infantiles. MÉTODOS: Esta investigación observacional prospectiva inscribió a un total de 459 pacientes con NAC infantil grave que acudieron a nuestro hospital entre abril de 2016 y diciembre de 2020, y se incluyeron como control 459 pacientes con NAC infantil leve/moderada. RESULTADOS: Los niveles de SIRT6 fueron notablemente más bajos en pacientes con NAC grave o pacientes fallecidos en comparación con los pacientes leves/moderados o con supervivencia, respectivamente. Todos los niveles de PCR, PCT e Interleukin-6 (IL-6) fueron significativamente más altos en pacientes con CAP fallecidos y los niveles séricos de SIRT6 se correlacionaron negativamente con los niveles séricos de CRP, PCT e IL-6. Los niveles más altos de PRISM, CRP, PCT e IL-6, así como una mayor tasa de mortalidad y niveles más bajos de PCIS se encontraron en pacientes con menor SIRT6 en comparación con los padres con mayor SIRT6. SIRT6 tenía potencial para el diagnóstico de NAC grave. CONCLUSIÓN: La SIRT6 regulada a la baja en pacientes infantiles con NAC grave predijo una mayor expresión de factores inflamatorios, resultados clínicos más graves y mal pronóstico.


Assuntos
Infecções Comunitárias Adquiridas , Pneumonia , Sirtuínas , Humanos , Criança , Interleucina-6 , Pró-Calcitonina , Proteína C-Reativa/análise , Biomarcadores , Prognóstico
9.
Dalton Trans ; 51(47): 18317-18328, 2022 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-36416140

RESUMO

Traditional approaches to synthesizing bismuth nanoparticle decorated carbon nitride (C3N4) materials suffer from the complex synthesis process and the addition of a surfactant, which is not conducive to environmental protection. To address these problems, we adopted a simple and green flux-assisted approach for the first time to fabricate metallic bismuth nanoparticle decorated C3N4 (BiCCN). Electron microscopy results suggested that bismuth vanadate was converted into small bismuth nanoparticles via the flux-assisted approach. Highly dispersed Bi nanoparticles dramatically intensify light absorption, facilitate spatial charge separation as electron acceptors, shorten the charge diffusion length, and reserve more active sites for generating reactive species via surface photo-redox reactions. Consequently, the derived optimized photocatalyst BiCCN-15 rendered around 26 times higher photocatalytic degradation efficiency toward an endocrine disrupting compound (bisphenol A) than C3N4. This work provides a novel approach for developing non-precious metal decorated photocatalytic materials for sustainable water decontamination.


Assuntos
Bismuto
10.
Artigo em Inglês | MEDLINE | ID: mdl-36429520

RESUMO

The Persulfate-based advanced oxidation process is the most efficient and commonly used technology to remove organic contaminants in wastewater. Due to the large surface area, unique electronic properties, abundant N functional groups, cost-effectiveness, and environmental friendliness, N-doped biochars (NBCs) are widely used as catalysts for persulfate activation. This review focuses on the NBC for oxidative degradation of organics-contaminated wastewater. Firstly, the preparation and modification methods of NBCs were reviewed. Then the catalytic performance of NBCs and modified NBCs on the oxidation degradation of organic contaminants were discussed with an emphasis on the degradation mechanism. We further summarized the detection technologies of activation mechanisms and the structures of NBCs affecting the PS activation, followed by the specific role of the N configuration of the NBC on its catalytic capacity. Finally, several challenges in the treatment of organics-contaminated wastewater by a persulfate-based advanced oxidation process were put forward and the recommendations for future research were proposed for further understanding of the advanced oxidation process activated by the NBC.


Assuntos
Carvão Vegetal , Águas Residuárias , Águas Residuárias/química , Carvão Vegetal/química , Oxirredução , Estresse Oxidativo
11.
J Colloid Interface Sci ; 628(Pt B): 831-839, 2022 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-36029597

RESUMO

The construction of hybrid catalysts composed of inorganic semiconductors and molecular catalysts shows great potential for achieving high photocatalytic carbon dioxide (CO2) conversion efficiency. In this study, ZnIn2S4 was first synthesized via a solvothermal route. Gold (Au) and silver (Ag) nanoparticles were then deposited on ZnIn2S4 via the reduction of noble metal precursor by sulfur vacancy defects. The obtained composite was further combined with tetra(4-carboxyphenyl)porphyrin iron(III) chloride (FeTCPP) molecular catalyst for efficient photocatalytic CO2 conversion. The roles of different noble metal nanoparticles in charge separation and interfacial electron transfer have been comprehensively studied. The photocatalytic performance and photoelectrochemical characterizations demonstrate that the introduction of Ag or Au nanoparticles is beneficial for charge separation. More importantly, the presence of Ag nanoparticles plays a crucial role in promoting the interfacial charge transfer between ZnIn2S4 and FeTCPP, whereas, Au nanoparticles function as active sites for the water reduction reaction.

12.
J Hazard Mater ; 435: 128939, 2022 08 05.
Artigo em Inglês | MEDLINE | ID: mdl-35483264

RESUMO

Ru species were loaded on a two-dimensional (2D) material of graphitic carbon nitride (2D g-C3N4) to serve as the efficient AOP catalysts. The catalytic activity was closely related to the dispersion degree of Ru, as determined by the inherent nanoarchitecture of the supporting material. Ultrathin g-C3N4 nanosheets with a unique porous structure were fabricated by further thermally oxidizing and etching bulk g-C3N4 (bCN) in air. Homogeneous dispersion of Ru species was successfully achieved on the porous few-layered g-C3N4 nanosheets (pCN) by stirring, washing, freeze drying and annealing processes to obtain Ru-pCN catalysts, whereas bCN or multilayered g-C3N4 (mCN) led to the aggregation of Ru nanoparticles in Ru-bCN and Ru-mCN materials. The conventional impregnation method also caused the resulting Ru-pCN-imp catalyst with undesirable Ru aggregation in spite of employing pCN. The optimal 4.4Ru-pCN removed 100% of 2,4,6-trichlorophenol (TCP) within only 3 min, superior to its counterpart samples, and exhibited remarkable degradation efficiencies for methyl orange, neutral red, 4-chlorophenol, tetracycline and oxytetracycline. Mechanistic studies suggested that four radicals, e.g., •OH, SO4• -, O2• - and 1O2 were generated during the peroxymonosulfate (PMS) activation, in which SO4• - and 1O2 played a major role.


Assuntos
Poluentes Ambientais , Peróxidos , Porosidade
13.
J Hazard Mater ; 434: 128866, 2022 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-35413519

RESUMO

Solar-driven advanced oxidation processes (AOPs) via direct photodegradation or indirect photocatalytic activation of typical oxidants, such as hydrogen peroxide (H2O2), peroxymonosulfate (PMS), and peroxydisulfate (PDS), have been deemed to be an efficient technology for wastewater remediation. Artificial Z-scheme structured materials represent a promising class of photocatalysts due to their spatially separated charge carriers and strong redox abilities. Herein, we summarize the development of metal-free graphitic carbon nitride (g-C3N4, CN)-based direct and indirect Z-scheme photocatalysts for solar-driven AOPs in removing organic pollutants from water. In the work, the classification of AOPs, definition and validation of Z-schemes are summarized firstly. The innovative engineering strategies (e.g., morphology and dimensionality control, element doping, defect engineering, cocatalyst loading, and tandem Z-scheme construction) over CN-based direct Z-scheme structure are then examined. Rational design of indirect CN-based Z-scheme systems using different charge mediators, such as solid conductive materials and soluble ion pairs, is further discussed. Through examining the relationship between the Z-scheme structure and activity (charge transfer and separation, light absorption, and reaction kinetics), we aim to provide more insights into the construction strategies and structure modification on CN-based Z-schemes towards improving their catalytic performances in AOPs. Lastly, limitations, challenges, and perspectives on future development in this emerging field are proposed.

14.
Environ Sci Pollut Res Int ; 29(37): 56379-56392, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35334050

RESUMO

Carbon quantum dots (CQDs) can be used to modify TiO2 to extend the light absorption threshold and enhance its photocatalytic efficiency. In this study, different amounts of CQDs modified TiO2 (CQDs-x/TiO2) were synthesized by a facile, mild, and environmental friendly hydrothermal method at a low temperature. The physicochemical properties were investigated by a variety of advanced characterization techniques. It was found that the anchoring of CQDs endowed the CQDs-x/TiO2 with a large specific surface area, which is beneficial to adsorb more organic pollutants and promote the rate of photocatalytic oxidation. The XRD results also showed that the in situ formation of CQDs on the surface of TiO2 made the crystallinity of TiO2 tend to be complete. Among these photocatalysts, CQDs-20/TiO2 showed the highest pollutant removal efficiency under visible light irradiations. The classical quenching tests revealed that the O2•-, •OH, and hole (h+) were the oxidizing species. Among them, h+ was the primary factor contributing to the degradation. The electrochemical tests showed that the anchoring of CQDs on TiO2 increased the photocurrent by about four times, as compared with the pure TiO2. In particular, the cyclic voltammetry results showed that the photo-generated electrons of CQDs were freer to transfer to TiO2 under visible light irradiations, promoting the separation of photo-generated electrons and holes. This study explains adequately why the CQDs/TiO2 system has a good photocatalytic degradation of organic compounds.

15.
Zhongguo Fei Ai Za Zhi ; 25(3): 137-146, 2022 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-35340156

RESUMO

BACKGROUND: The literature recommends that reduced dosage of CPT-11 should be applied in patients with UGT1A1 homozygous mutations, but the impact of UGT1A1 heterozygous mutations on the adverse reactions of CPT-11 is still not fully clear. METHODS: A total of 107 patients with UGT1A1 heterozygous mutation or wild-type, who were treated with CPT-11 from January 2018 to September 2021 in Peking University Third Hospital, were retrospectively enrolled. The adverse reaction spectra of patients with UGT1A1*6 and UGT1A1*28 mutations were analyzed. Adverse reactions were evaluated according to National Cancer Institute Common Terminology Criteria for Adverse Events (NCI-CTCAE) 5.0. The efficacy was evaluated according to Response Evaluation Criteria in Solid Tumors (RECIST) 1.1. The genotypes of UGT1A1*6 and UGT1A1*28 were detected by digital fluorescence molecular hybridization. RESULTS: There were 43 patients with UGT1A1*6 heterozygous mutation, 26 patients with UGT1A1*28 heterozygous mutation, 8 patients with UGT1A1*6 and UGT1A1*28 double heterozygous mutations, 61 patients with heterozygous mutation at any gene locus of UGT1A1*6 and UGT1A1*28. Logistic regression analysis showed that the presence or absence of vomiting (P=0.013) and mucositis (P=0.005) was significantly correlated with heterozygous mutation of UGT1A1*28, and the severity of vomiting (P<0.001) and neutropenia (P=0.021) were significantly correlated with heterozygous mutation of UGT1A1*6. In colorectal cancer, UGT1A1*6 was significantly correlated to diarrhea (P=0.005), and the other adverse reactions spectrum was similar to that of the whole patient cohort, and efficacy and prognosis were similar between patients with different genotypes and patients treated with reduced CPT-11 dosage or not. CONCLUSIONS: In clinical use, heterozygous mutations of UGT1A1*6 and UGT1A1*28 are related to the risk and severity of vomiting, diarrhea, neutropenia and mucositis in patients with Pan-tumor and colorectal cancer post CPT-11 therpy. In colorectal cancer, UGT1A1*6 is significantly related to diarrhea post CPT-11 use, efficacy and prognosis is not affected by various genotypes or CPT-11 dosage reduction.


Assuntos
Camptotecina , Glucuronosiltransferase , Neoplasias Pulmonares , Camptotecina/uso terapêutico , Glucuronosiltransferase/genética , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Mutação , Polimorfismo Genético , Estudos Retrospectivos
16.
J Colloid Interface Sci ; 615: 865-875, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35182856

RESUMO

Rational design with fine-tuning of the electrocatalyst material is vital for achieving the desired sensitivity, selectivity, and stability for an electrochemical sensor. In this study, a three-dimensional (3D) hierarchical core-shell catalyst was employed as a self-standing, binder-free electrode for non-enzymatic glucose sensing. The catalyst was prepared by decorating the shell of NiFe layered double hydroxide (LDH) nanosheets (NSs) on the core of Cu nanowires (NWs) grown on a Cu foam support. The optimized 3D core-shell Cu@NiFe LDH sensor demonstrated higher sensitivity (7.88 mA mM-1cm-2), lower limit of detection (0.10 µM) and wider linear range (1 µM to 0.9 mM) in glucose sensing with a low working potential (0.4 V). The applied sensor also showed excellent stability, reproducibility, interference ability as well as practicability in real environment. The detection of real samples further suggests its great feasibility for practical applications. The superior electrocatalytic performance is collectively ascribed to the excellent electro-conductivity of the Cu substrate, the distinct self-standing 3D porous nanostructure, the ultrathin homogenous architecture, and the appropriate loading amount of NiFe LDH NSs. This study then provides a non-enzymatic glucose sensor with 3D Cu@NiFe LDH electrode for ultrahigh sensitivity and stability.


Assuntos
Glucose , Nanofios , Eletrodos , Glucose/química , Hidróxidos , Nanofios/química , Reprodutibilidade dos Testes
17.
Langmuir ; 38(2): 828-837, 2022 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-34984900

RESUMO

Graphitic carbon nitride (g-C3N4) has attracted extensive research attention because of its virtues of a metal-free nature, feasible synthesis, and excellent properties. However, the low specific surface area and mediocre charge separation dramatically limit the practical applications of g-C3N4. Herein, porous nitrogen defective g-C3N4 (PDCN) was successfully fabricated by the integration of urea-assisted supramolecular assembly with the polymerization process. Advanced characterization results suggested that PDCN exhibited a much larger specific surface area and dramatically improved charge separation compared to bulk g-C3N4, leading to the formation of more active sites and the improvement in mass transfer. The synthesized PDCN rendered a 16-fold increase in photocatalytic tetracycline degradation efficiency compared to g-C3N4. Additionally, the hydrogen evolution rate of PDCN was 10.2 times higher than that of g-C3N4. Meanwhile, the quenching experiments and electron spin resonance (ESR) spectra suggested that the superoxide radicals and holes are the predominant reactive species for the photocatalytic degradation process. This study may inspire the new construction design of efficient g-C3N4-based visible-light photocatalysts.

18.
J Colloid Interface Sci ; 607(Pt 2): 1603-1612, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34592547

RESUMO

Crystalline carbon nitride is regarded as the new generation of emerging metal-free photocatalysts as opposed to polymeric carbon nitride (g-C3N4) because of its high crystalline structure and ultrahigh photocatalytic water splitting performance. However, further advances in crystalline g-C3N4 are significantly restricted by the sluggish separation of charge carriers and limited active sites. In this study, we demonstrate the successful synthesis of heptazine-triazine donor-acceptor-based ultrathin crystalline g-C3N4 nanosheets (UCCN) using a combined hot air exfoliation and molten salt (NaCl/KCl) copolymerization approach. The synergy of the donor-acceptor heterojunction and the ultrathin structure greatly accelerated the separation of the charge carriers and enriched the active sites. Accordingly, the superior hydrogen evolution activity and an ultrahigh apparent quantum efficiency of 73.6% at 420 nm under a natural photosynthetic environment were achieved by UCCN, positioning this material at the top among reported conjugated g-C3N4 materials. This study provides a novel paradigm for the development of donor-acceptor-based ultrathin crystalline layered materials.


Assuntos
Hidrogênio , Nitrilas , Água
19.
J Hazard Mater ; 423(Pt A): 127083, 2022 02 05.
Artigo em Inglês | MEDLINE | ID: mdl-34488092

RESUMO

Porous carbon serves as a green material for efficient wastewater purification by adsorption and advanced oxidation processes. However, a clear understanding of the simultaneous removal of multiple pollutants in water is still ambiguous. Herein, the synergistic effect of adsorption and peroxydisulfate (PS) activation on kinetics and mechanism of removing single and binary antibiotic pollutants, sulfamethoxazole (SMX) and ibuprofen (IBP), from water by biomass-derived N-doped porous carbon was investigated. Our findings suggest that adsorption contributed to efficient removals of SMX/IBP. Comparative quenching experiments and electrochemical analysis demonstrated that hydroxyl (•OH) and sulfate (SO4•-) radicals, as well as singlet oxygen (1O2) led to the catalytic degradation of SMX, while only 1O2 reacted for IBP oxidation. Superoxide ion (O2•-) radicals were not related to SMX/IBP degradation. Electron transfer pathway accounted for PS activation but was not involved in direct SMX/IBP oxidation. Only slight differences were found between the degradation kinetics of SMX and IBP in the binary and single SMX or IBP solutions. This arose from the non-selective effect of adsorption and 1O2 attack for SMX/IBP removal, and the weak selective oxidation process of SMX by •OH and SO4•-. This study provides a new viewpoint on the role of adsorption in catalysis and enriches the mechanistic study of multi-component antibiotic degradation.


Assuntos
Carbono , Poluentes Químicos da Água , Adsorção , Antibacterianos , Cinética , Porosidade , Poluentes Químicos da Água/análise
20.
Artigo em Inglês | MEDLINE | ID: mdl-34804183

RESUMO

OBJECTIVE: To identify the biological function and metabolic pathway of differential metabolites in follicular fluid of senile patients with kidney qi deficiency undergoing in vitro fertilization-embryo transfer (IVF-ET) and observe the effect of kidney-invigorating herbs on IVF outcomes in senile patients. METHODS: A total of 95 women undergoing IVF treatment were recruited and divided into three groups, including 34 cases in the treatment group (the senile patients with kidney qi deficiency after the intervention of Chinese medicine), 31 cases in the experiment group (the senile patients with kidney qi deficiency of no intervention of Chinese medicine), and 30 cases in the control group (young women with infertility due to male factor). The three groups of women were treated with long protocol ovarian hyperstimulation; the treatment group was given Qi-Zi-Yu-Si decoction on the day of HCG downregulation. Their IVF clinical outcomes were observed. The metabolites changes of kidney qi deficiency syndrome were analyzed in follicular fluid metabolomics using liquid chromatography-mass spectrometry (UPLC-MS/MS). RESULTS: The syndrome score of kidney qi deficiency syndrome in the treatment group was significantly improved after treatment (P < 0.01). Compared with the experiment group, the available embryo rate and implantation rate were increased, and the difference was statistically significant (P < 0.05). Progesterone, indoleacrylic acid, 2-propenyl 1-(1-propenylsulfinyl) propyl disulfide, N-acetyltryptophan, decanoylcarnitine, 20a-dihydroprogesterone, testosterone acetate, eicosatrienoic acid, 1H-indole-3-carboxaldehyde, choline, phosphorylcholine, and tryptophan were downregulated in the treatment group. Through pathway analysis, glycerophospholipid metabolism and steroid hormone biosynthesis were regulated in senile patients with kidney qi deficiency after Qi-Zi-Yu-Si decoction intervention. CONCLUSION: Qi-Zi-Yu-Si decoction can effectively improve the IVF outcome and clinical symptoms of senile patients. Follicular fluid metabolites were significantly changed in senile infertile women with kidney qi deficiency, and the mechanism by which kidney-invigorating herbs improve IVF treatment outcomes may be related to glycerophospholipid metabolism and steroid hormone biosynthesis. This study was registered in the Chinese Clinical Trials Registry Platform (ChiCTR1800014422).

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