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1.
J Colloid Interface Sci ; 652(Pt A): 912-922, 2023 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-37634364

RESUMO

The utilization of photo-assisted persulfate activation for the removal of organic contaminants in water has garnered significant research interest in recent times. However, there remains a lack of clarity regarding specific contributions of light irradiation and catalyst structure in this process. Herein, a photo-assisted peroxymonosulfate (PMS) activation system is designed for the highly efficient degradation of organic contaminants on oxygen vacancy-enriched nolanites (Vo-FVO). Results suggest that the degradation of bisphenol A (BPA) in this system is a nonradical-dominated process via an electron transfer regime, in which VO improves the local electron density and thus facilitates the electron shuttling between BPA and PMS. During BPA degradation, PMS adsorbed at the surface of FVO-180 withdraws electrons near VO and forms FVO-PMS* complexes. Upon light irradiation, photoelectrons effectively restore the electron density around VO, thereby enabling a sustainable electron transfer for the highly efficient degradation of BPA. Overall, this work provides new insights into the mechanism of persulfate activation based on defects engineering in nolanite minerals.

2.
Front Genet ; 13: 904168, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35719389

RESUMO

Colorectal cancer (CRC) represents one of the most common malignancies with high morbidity worldwide. Growing evidence has suggested that platelets are a fundamental component of the tumor microenvironment and play crucial roles in driving tumor biological behavior. The construction of a platelet-related prognostic model that can reliably predict CRC prognosis is of great clinical significance. The 1427 CRC-specific platelet-related genes were collected and mainly enriched in the ribosome and immune-related pathways. Based on platelet-related genes, three subtypes of TCGA CRC samples were identified by consensus clustering and characterized by differences in angiogenesis, epithelial-mesenchymal transition, immune infiltration, and prognosis. A total of 100 prognostic platelet-related genes were identified by univariate Cox regression. LASSO Cox regression further shrank those genes and constructed a 10-gene prognostic model. The patients with higher risk scores had significantly worse disease-specific survival than those with lower scores in both TCGA and validation cohorts. The risk score demonstrated good predictive performance for prognosis by receiver operating characteristic (ROC) curves. Furthermore, multivariate Cox regression analysis showed that the risk score was independent of TNM stage, sex, and age, and a graphic nomogram based on the risk score and clinical factors was developed to predict survival probability of CRC patients. Patients from the high-risk group were characterized by higher infiltration of immunosuppressive cells such as MDSC and Treg and higher expression of checkpoints CTLA4, CD86, and PDCD1LG2. Taken together, we identified three platelet-related subtypes and specifically constructed a promising 10-gene prognostic model in CRC. Our results highlighted the potential survival effects of platelet-related genes and provided evidence about their roles in regulating tumor immunity.

3.
J Hazard Mater ; 424(Pt C): 127596, 2022 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-34808448

RESUMO

The antibiotics pollution has currently captured increasing concerns due to its potential hazards to the environment and human health. The development of efficient and viable techniques for the removal of antibiotics is one of the research hotspots in fields of wastewater treatment and pharmaceutical industry. Although the photodegradation of antibiotics is widely studied, the evolution and toxicity of degradation intermediates have been rarely documented. Herein, Pt nanoparticles (NPs) decorated BiVO4 nanosheets (Pt/BiVO4 NSs) that exhibit excellent tetracycline (TC) photodegradation activity and stability have been prepared. Especially, the TC degradation efficiency reaches ca. 88.5% after 60 min under visible light irradiation, which is superior to most of the metal loaded two-dimensional photocatalysts reported hitherto. The excellent photocatalytic activity is attributable to the enhanced light absorption capacity and charge separation efficiency in Pt/BiVO4 NSs. h+, •O2- and •OH are the main active species for TC degradation, resulting in three possible degradation pathways. Furthermore, we first verify that TC solutions treated by Pt/BiVO4 NSs are harmless to Escherichia coli K-12 and various bacteria in natural rivers, which would not stimulate Escherichia coli to produce antibiotics resistance genes (ARGs). This work develops an environmentally friendly photodegradation strategy using Pt/BiVO4 NSs with potentials for efficient remediation of antibiotics pollution in wastewater.


Assuntos
Escherichia coli K12 , Vanadatos , Antibacterianos/toxicidade , Bismuto/toxicidade , Catálise , Humanos , Luz , Fotólise , Tetraciclina/toxicidade
4.
Nanoscale ; 12(28): 15169-15174, 2020 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-32662483

RESUMO

Visible-light-driven photocatalysts have shown tremendous prospects in solving the energy crisis and environmental problems, thanks to their wide spectral response and high quantum efficiency. Several strategies including the expansion of visible light response and the improvement of solar energy utilization and photocatalytic quantum efficiency via more effective separation of photogenerated carriers are the current focuses of research that direct the design and fabrication of viable photocatalysts. Herein, a series of composite photocatalysts assembled from plasmonic Cu nanoparticles (NPs) and Zn3In2S6 (ZIS) solid solutions were synthesized by means of a simple solvothermal method. In comparison with the pristine ZIS semiconductor, Cu NP loaded ZIS solid solutions showed greatly enhanced photocatalytic activity, selectivity and stability towards CO2 reduction under visible irradiation. Of note was that the optimized ZIS-Cu2 exhibited an enhanced CH4 production rate of ca. 292 µL g-1 h-1 and a selectivity of ca. 71.1%, which were among the highest numbers reported hitherto. The localized surface plasmon resonance (LSPR) effect, shown by surface Cu NPs, was believed to play a critical role in the enhanced CO2 photoreduction efficiency. More importantly, the introduction of plasmonic Cu NPs could restrain the recombination of photogenerated electron-hole pairs and promote the migration of photogenerated electrons to better participate in the photocatalytic CO2 reduction in the presence of water vapor. This work thus provides a facile means to design robust and flexible composite photocatalysts for visible-light-driven CO2 photoreduction with high efficiency.

5.
Chem Commun (Camb) ; 56(56): 7765-7768, 2020 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-32578604

RESUMO

A one-dimensional Cd0.6Zn0.4S nanorod (CZS NR) solid solution with rich sulfur vacancies achieved an excellent photocatalytic hydrogen production activity of 59.3 mmol h-1 g-1 under visible irradiation, which is the highest number observed for CdZnS solid solution nanomaterials to date.

6.
Water Res ; 179: 115882, 2020 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-32402862

RESUMO

Novel magnetic Ag@RF@Fe3O4 core-satellite (MCS) nanocomposites were prepared through in situ photoreduction upon bridging Fe(III) and Ag+ via hydroxyl groups in resorcinol formaldehyde (RF) resin by virtue of the coordination effect. The catalytic activity of MCS nanocomposites was evaluated based on catalytic 4-nitrophenol (4-NP) reduction with NaBH4 as the reducing agent. It was noteworthy that the MCS-3 was beneficial to obtain a superior reaction rate constant of 2.27 min-1 and a TOF up to 72.7 h-1. Moreover, the MCS could be easily recovered by applying an external magnetic field and was reused for five times without significantly decrease in catalytic activity. Kinetic and thermodynamic study revealed that catalytic 4-NP reduction using MCS nanocatalysts obeyed the Langmuir-Hinshelwood mechanism and was controlled by the diffusion rate of substrates. Overall, the immobilization of ultra-fine Ag nanoparticles and the extremely negative potentials around MCS nanocomposites, which were effective for the diffusion of reactants, synergistically accelerated the catalytic reduction reactions.


Assuntos
Nanopartículas Metálicas , Nanocompostos , Catálise , Compostos Férricos , Fenômenos Magnéticos , Nitrofenóis , Oxirredução , Prata
7.
Nat Commun ; 11(1): 310, 2020 01 21.
Artigo em Inglês | MEDLINE | ID: mdl-31964862

RESUMO

Regulations currently in force enable to claim that the lead content in perovskite solar cells is low enough to be safe, or no more dangerous, than other electronics also containing lead. However, the actual environmental impact of lead from perovskite is unknown. Here we show that the lead from perovskite leaking into the ground can enter plants, and consequently the food cycle, ten times more effectively than other lead contaminants already present as the result of the human activities. We further demonstrate that replacing lead with tin represents an environmentally-safer option. Our data suggest that we need to treat the lead from perovskite with exceptional care. In particular, we point out that the safety level for lead content in perovskite-based needs to be lower than other lead-containing electronics. We encourage replacing lead completely with more inert metals to deliver safe perovskite technologies.


Assuntos
Compostos de Cálcio/normas , Chumbo/normas , Mentha spicata/efeitos dos fármacos , Óxidos/normas , Poluentes do Solo/normas , Níveis Máximos Permitidos , Titânio/normas , Compostos de Cálcio/química , Compostos de Cálcio/toxicidade , Eletrônica/normas , Chumbo/toxicidade , Óxidos/química , Óxidos/toxicidade , Solo/química , Poluentes do Solo/toxicidade , Energia Solar/normas , Titânio/química , Titânio/toxicidade
8.
Environ Sci Pollut Res Int ; 26(30): 31055-31061, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31456150

RESUMO

Semiconductors are promising photocatalysts for the use of sunlight in energy conversion and environmental remediation. To this end, various synthetic pathways have been proposed to increase their photocatalytic efficiency, catalytic stability, recycle, and reuse. In this work, mixed phase CdS nanoparticles were loaded on the surface of activated biomass carbons to prepare composite photocatalysts via hydrothermal syntheses, which were further applied to photocatalytic degradation of rhodamine B (RhB) under visible irradiation. The composite photocatalysts displayed considerable specific surface area (up to 672 m2 g-1) and suitable band gap energy of ca. 2.1 eV. Due to the excellent light adsorption ability and chemical stability, these composite photocatalysts exhibited excellent photocatalytic capacity toward RhB degradation under visible irradiation. Moreover, the photocatalytic stability was also demonstrated by cyclic experiments, by which the composite photocatalysts retained over 80% of the initial catalytic activity after 4 consecutive runs.


Assuntos
Compostos de Cádmio/química , Nanopartículas/química , Rodaminas/química , Compostos de Selênio/química , Adsorção , Catálise , Carvão Vegetal/química , Luz , Processos Fotoquímicos , Semicondutores , Poluentes Químicos da Água/química
9.
Bioresour Technol ; 277: 128-135, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30665086

RESUMO

In view of the increasing concerns in antibiotics contamination, advanced technologies for antibiotics removal have been receiving widespread research attention in the fields of environmental sciences. This work has developed a series of amino-functionalized porous carbon materials (NH2-BPCs), via a facile chemical modification method, which have been found efficient for the removal of sulfonamide antibiotics from simulated wastewater. Studies on adsorption kinetics and isotherms of antibiotics in simulated aqueous phases indicated that the adsorption capacity of sulfadiazine (SDZ) by NH2-BPCs showed a large value under acidic conditions (pH < 5). Moreover, the adsorption rate constant of NH2-BPCs was greatly enhanced upon amino modification, which demonstrated faster and more effective adsorption efficiency for antibiotics removal. These results suggested that surface amino modification of porous carbons might be a viable pathway to increase the adsorption affinity and efficiency of antibiotics with great potentials for water remediation.


Assuntos
Antibacterianos/química , Biomassa , Carbono/química , Sulfonamidas/química , Águas Residuárias/química , Poluentes Químicos da Água/química , Adsorção , Cinética , Porosidade
10.
R Soc Open Sci ; 5(8): 180050, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30225003

RESUMO

An extensive study of the spatial distribution characteristics of potentially harmful elements (PHEs) in tea (Camellia sinensis (L.) O. Kuntze) garden soils and ecological risk assessment at An'xi County, the birthplace of oolong tea in China, was implemented. A total of 78 soil samples were examined to determine the concentration of five PHEs (As, Cd, Cr, Hg and Pb), soil organic matter and pH by using geostatistical approaches combined with geographical information system analysis. All PHEs presented in the study area were slightly higher than their background values for provincial and national standards except Cr. Moreover, ecological risk assessment of PHEs in the tea garden soils at An'xi County was performed by means of the Håkanson method. The average ecological potential risk index (Er) of the five PHEs followed a descending order of Cd > Hg > Pb > As > Cr, and suggested a moderate ecological risk in the study area.

11.
ACS Appl Mater Interfaces ; 9(6): 5231-5236, 2017 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-28165717

RESUMO

A conjugated microporous polymer (CMP) material was designed with pore function of cyano and pyridyl groups that act as potential binding sites for Ag+ ion capture. Ultrafine silver nanoparticles (less than 5 nm) were successfully supported on the predesigned CMP material to afford Ag0@CMP composite materials by means of a simple liquid impregnation and light-induced reduction method. Spherical Ag0 nanoparticles with a statistical mean diameter of ca. 3.9 nm were observed and characterized by scanning electron microscopy and transmission electron microscopy. The Ag0@CMP composite materials were consequently exploited as high-performance nanocatalysts for the reduction of nitrophenols, a family of priority pollutants, at various temperatures and ambient pressure. Moreover, the composite nanocatalysts feature convenient recovery and excellent reusability. This work presents an efficient platform to achieve ultrafine metal nanoparticles immobilized on porous supports with predominant catalytic properties by virtue of the structural design and spatial confinement effect available for conjugated microporous polymers.

12.
Front Chem ; 5: 123, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29326925

RESUMO

A family of new composite materials was successfully prepared through the deposition of as-synthesized CdS nanomaterials on lotus-seedpod-derived activated carbon (SAC). The SAC supports derived at different activation temperatures exhibited considerably large surface areas and various microstructures that were of great importance in enhancing photocatalytic performance of CdS@SAC composite materials toward the photodegradation of rhodamine B (RhB) under visible irradiation. The best-performing CdS@SAC-800 showed excellent photocatalytic activity with a rate constant of ca. 2.40 × 10-2 min-1, which was approximately 13 times higher than that of the CdS nanomaterials. Moreover, the estimated band gap energy of CdS@SAC-800 was significantly lowered down to 1.99 eV compared to that of the CdS precursor (2.22 eV), which suggested considerable strength of interface contact between the CdS and SAC support, as well as efficient light harvesting capacity of the composite material. Further photocatalytic study indicated that the SAC supports enhanced the separation of photogenerated electrons and holes in this system. Improved photocatalytic activity of the composite materials was largely due to the increased generation of catalytically active species such as h+, OH•, [Formula: see text] etc. This work provided a facile and low-cost pathway to fabricate photocatalysts for viable degradation of organic dye molecules.

13.
J Environ Sci (China) ; 22(1): 56-61, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20397387

RESUMO

High-concentration nitrite-containing wastewater that presents extreme toxicity to human health and organisms is difficult to be treated using traditional biological process. In this study, a novel microwave-enhanced chemical reduction process (MECRP) using sulfaminic acid (SA) was proposed as a new manner to treat such type of wastewater. Based on lab-scale experiments, it was shown that 75%-80% nitrite (NO2-) could be removed within time as short as 4 min under 50 W microwave irradiation in pH range 5-10 when molar ratio of SA to nitrite (SA/NO2-) was 0.8. Pilot-scale investigations demonstrated that MECRP was able to achieve nitrite and chemical oxygen demand (COD) removal with efficiency up to 80% and 20%, respectively under operating conditions of SA concentration 80 kg/m3, SA/NO2- ratio 0.8, microwave power 3.4 kW, and stirring time 3 min. Five-day biological oxygen demand (BOD5)/COD value of treated effluent after MECRP was increased from 0.05 to 0.36 (by 620%), which clearly suggested a considerable improvement of biodegradability for subsequent biological treatment. This study provided a demonstration of using microwave irradiation to enhance reaction between SA and nitrite in a short time, in which nitrite in wastewater was completely converted into nitrogen gas without leaving any sludge and secondary pollutants.


Assuntos
Micro-Ondas , Nitritos/química , Ácidos Sulfônicos/química , Eliminação de Resíduos Líquidos/métodos , Poluentes Químicos da Água/química , Oxirredução , Projetos Piloto
14.
J Hazard Mater ; 168(2-3): 895-900, 2009 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-19345484

RESUMO

Experiments were conducted to investigate the removal of remazol golden yellow dye in order to assess the effectiveness and feasibility of microwave enhanced chlorine dioxide (ClO(2)) catalytic oxidation process. The catalyst used in this process was CuO(n)-La(2)O(3)/gamma-Al(2)O(3). The operating parameters such as the ClO(2) dosage, catalyst dosage, and pH were evaluated. The results showed that microwave enhanced catalytic oxidation process could effectively degrade remazol golden yellow dye with low oxidant dosage in a short reaction time and extensive pH range compared to the conventional wet catalytic oxidation. Under the optimal condition (ClO(2) concentration 80 mg/L, microwave power 400 W, contacting time 1.5 min, catalyst dosage 70 g/L, and pH 7), color removal efficiency approached 94.03%, corresponding to 67.92% of total organic carbon removal efficiency. It was found that the fluorescence intensity in microwave enhanced ClO(2) catalytic oxidation system was about 500a.u. which was verified that there was much hydroxyl radical produced. Compared with different processes, microwave enhanced ClO(2) catalytic oxidation system could significantly enhance the degradation efficiency. It provides an effective technology for dye wastewater treatment.


Assuntos
Compostos Clorados/química , Corantes/química , Micro-Ondas , Óxidos/química , Catálise , Estudos de Viabilidade , Concentração de Íons de Hidrogênio , Oxirredução
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