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1.
Sci Total Environ ; 917: 170570, 2024 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-38296071

RESUMO

Ground-level ozone (O3) pollution poses significant threats to both human health and air quality. This study uses ground observations and satellite retrievals to explore the spatiotemporal characteristics of ground-level O3 in Zhejiang Province, China. We created data-driven machine learning models that include meteorological, geographical and atmospheric parameters from multi-source remote sensing products, achieving good performance (Pearson's r of 0.81) in explaining regional O3 dynamics. Analyses revealed the crucial roles of temperature, relative humidity, total column O3, and the distributions and interactions of precursor (volatile organic compounds and nitrogen oxides) in driving the varied O3 patterns observed in Zhejiang. Furthermore, the interpretable modeling quantified multifactor interactions that sustain high O3 levels in spring and autumn, suppress O3 levels in summer, and inhibit O3 formation in winter. This work demonstrates the value of a combined approach using satellite and machine learning as an effective novel tool for regional air quality assessment and control.

2.
J Colloid Interface Sci ; 656: 155-167, 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-37989049

RESUMO

The electrocatalytic conversion of nitric oxide (NORR) to ammonia (NH3) represents a pivotal approach for sustainable energy transformation and efficient waste utilization. Designing highly effective catalysts to facilitate the conversion of NO into NH3 remains a formidable challenge. In this work, the density functional theory (DFT) is used to design NORR catalysts based on single and double transition metal (TM:Fe, Co, Ni and Cu) atoms supported by graphdiyne (TM@GDY). Among eight catalysts, the Cu2@GDY is selected as a the most stable NORR catalyst with high NH3 activity and selectivity. A pivotal discovery underscores that the NORR mechanism is thermodynamically constrained on single atom catalysts (SACs), while being governed by electrochemical processes on double atom catalysts (DACs), a distinction arising from the different d-band centers of these catalysts. Therefore, this work not only introduces an efficient NORR catalyst but also provides crucial insights into the fundamental parameters influencing NORR performance.

3.
Chem Commun (Camb) ; 59(97): 14435-14438, 2023 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-37982192

RESUMO

IL/ICOF composites were in situ synthesized via a one-pot route in half an hour under ambient conditions for catalytic cycloaddition of CO2 with epoxides into cyclic carbonates. The prepared composites feature a decent CO2 adsorption capacity of 1.63 mmol g-1 at 273 K and 1 bar and exhibit excellent catalytic performance in terms of yield and durability. This work may pave a new way to design and construct functionalized porous organic frameworks as heterogeneous catalysts for CO2 capture and conversion.

4.
ACS Appl Mater Interfaces ; 13(26): 30458-30467, 2021 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-34159788

RESUMO

Liquid ammonia is considered a sustainable liquid fuel and an easily transportable carrier of hydrogen energy; however, its synthesis processes are energy-consuming, high cost, and low yield rate. Herein, we report the electrocatalytic reduction of nitrate (NO3-) (ERN) to ammonia (NH3) with nickel phosphide (Ni2P) used as a noble metal-free cathode. Ni2P with (111) facet was grown in situ on nickel foam (NFP), which was regarded as a self-supporting cathode for ERN to synthesis NH3 with high yield rate (0.056 mmol h-1 mg-1) and superior faradaic efficiency of 99.23%. The derived atomic H (*H), verified by a quenching experiment and an electron spin resonance (ESR) technique, effectively enhanced the high selectivity for NH3 generation. DFT calculations indicated that *NO3 was deoxygenated to *NO2 and *NO, and *NO was subsequently hydrogenated with *H to generate NH3 with an energy releasing process (ΔG < 0). OLEMS also proved that NO was the merely gas intermediate. NFP exhibited the unique superhydrophilic surface, metallic properties, low impedance, and abundant surface sites, favorable for adsorption of NO3-, generation of *H, and then hydrogenation of NO3-. Hence, NFP cathode showed high selectivity for NH3 (89.1%) in ERN. NFP with long-term stability and low energy consumption provides a facile strategy for synthesis of NH3 and elimination of NO3- contamination.

5.
J Environ Sci (China) ; 91: 10-21, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32172958

RESUMO

The widely used carbamazepine (CBZ) is one of the most persistent pharmaceuticals and suffers insufficient removal efficiency by conventional wastewater treatment. A synthesized Co-based perovskite (LaCoO3) was used to activate peroxymonosulfate (PMS) in order to degrade CBZ. Results showed that LaCoO3 exhibited an excellent performance in PMS activation and CBZ degradation at neutral pH, with low cobalt leaching. The results of FT-IR and XPS verified the high structurally and chemically stability of LaCoO3 in PMS activation. Electron spin resonance (ESR) analysis suggested the generation of radical species, such as sulfate radicals (SO4-) and hydroxyl radicals (OH). Radical quenching experiments further revealed the responsibility of SO4- as the dominant oxidant for CBZ oxidation. Ten products were detected via the oxidation of CBZ, with the olefinic double bond attacked by SO4- as the initial step. Hydroxylation, hydrolysis, cyclization and dehydration were involved along the transformation of CBZ. The toxicity of CBZ solution was significantly reduced after treating by PMS/LaCoO3.


Assuntos
Lantânio , Poluentes Químicos da Água/análise , Compostos de Cálcio , Carbamazepina , Minerais , Óxidos , Peróxidos , Espectroscopia de Infravermelho com Transformada de Fourier , Titânio
6.
Water Res ; 165: 114930, 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31426006

RESUMO

Nickel phosphide (Ni2P) is an emerging efficient catalyst for the hydrogen evolution and water splitting. Herein, we report that Ni2P is also a promising catalyst for enhancing electrochemical dechlorination of chlorinated disinfection byproducts (DBPs). Amorphous Ni2P (ANP) mini-nanorod arrays were in-situ fabricated on nickel foam (NF) via a facile phosphidation process, and then used as a binder-free cathode for electrochemical dechlorination of trichloroacetic acid (TCAA). Results showed that ANP exhibited superior performance on electrochemical dechlorination of TCAA than other metal cathodes (e.g., NF and Pd/C). Scavenging experiments and electron spin resonance (ESR) technique indicated that atomic H* was generated from water reduction through ANP catalysis, and primarily contributed to TCAA dechlorination. Indeed, the superhydrophilic surface of ANP favored electrocatalyst/electrolyte contact, and its low impedance further afforded rapid electron transport from the electrode to water or protons for atomic H* generation. The kinetic modelling and mass balance evaluation revealed the transformation mechanism of TCAA dechlorination. This study is among the first to develop ANP as a binder-free cathode for electrochemical dechlorination, and have important implications for eliminating chlorinated DBPs in water.


Assuntos
Halogenação , Níquel , Catálise , Eletrodos , Hidrogênio
7.
Sci Rep ; 8(1): 12633, 2018 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-30115987

RESUMO

A correction to this article has been published and is linked from the HTML and PDF versions of this paper. The error has not been fixed in the paper.

8.
Sci Rep ; 8(1): 5121, 2018 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-29572518

RESUMO

The purpose of this study was to develop a rapid and green method for the synthesis of lignocelluloses-based materials with superior mechanical properties. Samples were produced by hot-pressed method using different concentrations of CaCO3 and poly (methyl methacrylate) particles-filled nanolignocelluloses composites which was synthesized through mechano-chemical method. Poly (methyl methacrylate) and CaCO3 nanoparticles have been used as nanofillers. Bending strength, elasticity modulus, and dimensional stability, thermal properties of the developed lignocelluloses-based composites were determined. In view of the experimental results, it is found that the composites materials have good mechanical, dimensional stability, and thermal properties which enhanced as the filler loading increased. Thus, herein described lignocelluloses-based materials showed important characteristics to be concluded that these composites are suitable to be used for the design of flooring and construction systems.

9.
Materials (Basel) ; 10(3)2017 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-28772670

RESUMO

Cellulose nanofiber/AlOOH aerogel for flame retardant and thermal insulation was successfully prepared through a hydrothermal method. Their flame retardant and thermal insulation properties were investigated. The morphology image of the cellulose nanofiber/AlOOH exhibited spherical AlOOH with an average diameter of 0.5 µm that was wrapped by cellulose nanofiber or adhered to them. Cellulose nanofiber/AlOOH composite aerogels exhibited excellent flame retardant and thermal insulation properties through the flammability test, which indicated that the as-prepared composite aerogels would have a promising future in the application of some important areas such as protection of lightweight construction materials.

10.
Nanomaterials (Basel) ; 7(6)2017 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-28545233

RESUMO

In this study, nanooctahedra MnFe2O4 were successfully deposited on a wood surface via a low hydrothermal treatment by hydrogen bonding interactions. As-prepared MnFe2O4/wood composite (MW) had superior performance of soft magnetism, fire resistance and electromagnetic wave absorption. Among them, small hysteresis loops and low coercivity (<±5 Oe) were observed in the magnetization-field curve of MW with saturation magnetization of 28.24 emu/g, indicating its excellent soft magnetism. The MW also exhibited a good fire-resistant property due to its initial burning time at 20 s; while only 6 s for the untreated wood (UW) in combustion experiments. Additionally, this composite revealed good electromagnetic wave absorption with a minimum reflection loss of -9.3 dB at 16.48 GHz. Therefore, the MW has great potential in the fields of special decoration and indoor electromagnetic wave absorbers.

11.
Sci Rep ; 7(1): 1823, 2017 05 12.
Artigo em Inglês | MEDLINE | ID: mdl-28500310

RESUMO

Nacre, the gold standard for biomimicry, provides an excellent example and guideline for assembling high-performance composites. Inspired by the layered structure and extraordinary strength and toughness of natural nacre, nacre-like nanolignocellulose/poly (vinyl alcohol)/TiO2 composites possessed the similar layered structure of natural nacre were constructed through hot-pressing process. Poly (vinyl alcohol) and TiO2 nanoparticles have been used as nanofillers to improve the mechanical performance and synchronously endow the superior photocatalytic activity of the composites. This research would be provided a promising candidate for the photooxidation of volatile organic compounds also combined with outstanding mechanical property.


Assuntos
Álcoois , Materiais Biomiméticos , Nácar , Titânio , Álcoois/química , Materiais Biomiméticos/química , Catálise , Teste de Materiais , Fenômenos Mecânicos , Nácar/química , Processos Fotoquímicos , Espectrofotometria Ultravioleta , Espectroscopia de Infravermelho com Transformada de Fourier , Titânio/química , Difração de Raios X
12.
Sci Rep ; 7(1): 1418, 2017 05 03.
Artigo em Inglês | MEDLINE | ID: mdl-28469169

RESUMO

In this study, we employed pyrolysis behavior and kinetics by Flynn-Wall-Ozawa method and Friedman method to analysis the thermostability of the MnFe2O4 nanoparticles/poplar wood composite, and analyzed the change of different proportion of MnFe2O4 in these composites for the thermostability by contrasting activation energy between the different samples. The pyrolysis processes of these composites were comprehensively investigated at different heating rates (10, 20, 30 and 40 °C/min-1) and pyrolysis temperatures of 600 °C in N2 and air atmosphere. These results indicated the thermostability of composites improved as the proportion of the MnFe2O4 nanoparticles increased. And the structure analyses of these composites from the microscopic view point of nanoparticles were applied to analysis the reason of thermostability enhancement of the poplar wood after coating MnFe2O4 nanoparticles. Additionally, due to its high initial oxidative decomposition temperature under air atmosphere, this composite and its preparation method might have high application potential, such as flameresistant material and wood security storage. This method also could provide a reference for other biomass materials. Synthesized MnFe2O4/C composite under the guidance of pyrolysis behaviors and kinetic study in N2 atmosphere exhibited good adsorption capacity (84.18 mg/g) for removing methylene blue dye in aqueous solution and easy separation characteristic.

13.
Carbohydr Polym ; 168: 265-273, 2017 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-28457449

RESUMO

A self-reporting aerogel toward stress sensitive slectricity (SSE) was presented using an interconnected 3D fibrous network of Ag nanoparticles/cellulose nanofiber aerogel (Ag/CNF), which was prepared via combined routes of silver mirror reaction and ultrasonication. Sphere-like Ag nanoparticles (AgNPs) with mean diameter of 74nm were tightly anchored in the cellulose nanofiber through by the coherent interfaces as the conductive materials. The as-prepared Ag/CNF as a self-reporting material for SSE not only possessed quick response and sensitivity, but also be easily recovered after 100th compressive cycles without plastic deformation or degradation in compressive strength. Consequently, Ag/CNF could play a viable role in self-reporting materials as a quick electric-stress responsive sensor.

14.
Sci Rep ; 7: 45914, 2017 04 03.
Artigo em Inglês | MEDLINE | ID: mdl-28368045

RESUMO

Cellulose nanofibril/graphene oxide hybrid (CNF/GO) aerogel was fabricated via a one-step ultrasonication method for adsorptive removal of 21 kinds of antibiotics in water. The as-prepared CNF/GO aerogel possesses interconnected 3D network microstructure, in which GO nanosheets with 2D structure were intimately grown along CNF through hydrogen bonds. The aerogel exhibited superior adsorption capacity toward the antibiotics. The removal percentages (R%) of the antibiotics were more than 69% and the sequence of six categories antibiotics according to the adsorption efficiency was as follows: Tetracyclines > Quinolones > Sulfonamides > Chloramphenicols > ß-Lactams > Macrolides. The adsorption mechanism was proposed to be electrostatic attraction, p-π interaction, π-π interaction and hydrogen bonds. In detail, the adsorption capacities of CNF/GO aerogel were 418.7 mg·g-1 for chloramphenicol, 291.8 mg·g-1 for macrolides, 128.3 mg·g-1 for quinolones, 230.7 mg·g-1 for ß-Lactams, 227.3 mg·g-1 for sulfonamides, and 454.6 mg·g-1 for tetracyclines calculated by the Langmuir isotherm models. Furthermore, the regenerated aerogels still could be repeatedly used after ten cycles without obvious degradation of adsorption performance.


Assuntos
Antibacterianos/isolamento & purificação , Celulose/química , Grafite/química , Nanofibras/química , Óxidos/química , Poluentes Químicos da Água/isolamento & purificação , Adsorção , Algoritmos , Antibacterianos/química , Géis , Ligação de Hidrogênio , Modelos Teóricos , Nanofibras/ultraestrutura , Reprodutibilidade dos Testes , Eletricidade Estática , Purificação da Água/métodos
15.
Sci Rep ; 6: 35549, 2016 10 17.
Artigo em Inglês | MEDLINE | ID: mdl-27748420

RESUMO

In this work, lamellar MnFe2O4 was successfully planted on a wood surface through the association of hydrogen bonds via the one-pot hydrothermal method. Simultaneously, the fluoroalkylsilane (FAS-17) on the surface of the MnFe2O4 layer formed long-chain or network macromolecules through a poly-condensation process and provided a lower surface energy on the wood surface. The MnFe2O4/wood composite (FMW) presented superior superparamagnetism, superhydrophobicity and electromagnetic wave absorption performance. The results indicated a saturation magnetization of the FMW with excellent superparamagnetism of 28.24 emu·g-1. The minimum value of reflection loss of the FMW reached -8.29 dB at 16.39 GHz with a thickness of 3 mm. Even after mechanical impact and exposure to corrosive liquids, the FMW still maintained a superior superhydrophobicity performance.

16.
Sci Rep ; 6: 35505, 2016 10 24.
Artigo em Inglês | MEDLINE | ID: mdl-27775091

RESUMO

In the present paper, uniformly large-scale wurtzite-structured ZnO nanorod arrays (ZNAs) were deposited onto a wood surface through a one-step solvothermal method. The as-prepared samples were characterized by X-ray diffraction (XRD), field-emission scanning electron microscopy (FE-SEM), transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FTIR), thermogravimetry (TG), and differential thermal analysis (DTA). ZNAs with a diameter of approximately 85 nm and a length of approximately 1.5 µm were chemically bonded onto the wood surface through hydrogen bonds. The superamphiphobic performance and ultraviolet resistance were measured and evaluated by water or oil contact angles (WCA or OCA) and roll-off angles, sand abrasion tests and an artificially accelerated ageing test. The results show that the ZNA-treated wood demonstrates a robust superamphiphobic performance under mechanical impact, corrosive liquids, intermittent and transpositional temperatures, and water spray. Additionally, the as-prepared wood sample shows superior ultraviolet resistance.

17.
Sci Rep ; 6: 32383, 2016 08 26.
Artigo em Inglês | MEDLINE | ID: mdl-27562532

RESUMO

The lignin aerogels that are both high porosity and compressibility would have promising implications for bioengineering field to sound-adsorption and damping materials; however, creating this aerogel had a challenge to adhesive lignin. Here we reported cellulose as green adhesion agent to synthesize the aerogels with strong mechanical performance. Our approach-straightforwardly dissolved in ionic liquids and simply regenerated in the deionized water-causes assembly of micro-and nanoscale and even molecule level of cellulose and lignin. The resulting lignin aerogels exhibit Young's modulus up to 25.1 MPa, high-efficiency sound-adsorption and excellent thermal insulativity. The successful synthesis of this aerogels developed a path for lignin to an advanced utilization.


Assuntos
Celulose/química , Géis/química , Lignina/química , Nanofibras/química , Adsorção/efeitos dos fármacos , Fenômenos Biomecânicos , Adesão Celular/efeitos dos fármacos , Lignina/biossíntese , Propriedades de Superfície , Condutividade Térmica , Água/química
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