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1.
Inorg Chem ; 63(1): 881-890, 2024 Jan 08.
Artículo en Inglés | MEDLINE | ID: mdl-38130105

RESUMEN

CO2 methanation has attracted considerable attention as a promising strategy for recycling CO2 and generating valuable methane. This study presents a niobium-doped CeO2-supported Ni catalyst (Ni/NbCe), which demonstrates remarkable performance in terms of CO2 conversion and CH4 selectivity, even when operating at a low temperature of 250 °C. Structural analysis reveals the incorporation of Nb species into the CeO2 lattice, resulting in the formation of a Nb-Ce-O solid solution. Compared with the Ni/CeO2 catalyst, this solid solution demonstrates an improved spatial distribution. To comprehend the impact of the Nb-Ce-O solid solution on refining the electronic properties of the Ni-Ce interfacial sites, facilitating H2 activation, and accelerating the hydrogenation of CO2* into HCOO*, in situ diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) analysis and density functional theory (DFT) calculations were conducted. These investigations shed light on the mechanism through which the activity of CO2 methanation is enhanced, which differs from the commonly observed CO* pathway triggered by oxygen vacancies (OV). Consequently, this study provides a comprehensive understanding of the intricate interplay between the electronic properties of the catalyst's active sites and the reaction pathway in CO2 methanation over Ni-based catalysts.

2.
Phys Chem Chem Phys ; 26(19): 14407-14419, 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38712898

RESUMEN

The electrocatalytic carbon dioxide reduction reaction (CO2RR) presents a viable and cost-effective approach for the elimination of CO2 by transforming it into valuable products. Nevertheless, this process is impeded by the absence of exceptionally active and stable catalysts. Herein, a new type of electrocatalyst of transition metal (TM)-doped ß12-borophene (TM@ß12-BM) is investigated via density functional theory (DFT) calculations. Through comprehensive screening, two promising single-atom catalysts (SACs), Sc@ß12-BM and Y@ß12-BM, are successfully identified, exhibiting high stability, catalytic activity and selectivity for the CO2RR. The C1 products methane (CH4) and methanol (CH3OH) are synthesized with limiting potentials (UL) of -0.78 V and -0.56 V on Sc@ß12-BM and Y@ß12-BM, respectively. Meanwhile, CO2 is more favourable for reduction into the C2 product ethanol (CH3CH2OH) compared to ethylene (C2H4) via C-C coupling on these two SACs. More importantly, the dynamic barriers of the key C-C coupling step are 0.53 eV and 0.73 eV for the "slow-growth" sampling approach in the explicit water molecule model. Furthermore, Sc@ß12-BM and Y@ß12-BM exhibit higher selectivity for producing C1 compounds (CH4 and CH3OH) than C2 (CH3CH2OH) in the CO2RR. Compared with Sc@ß12-BM, Y@ß12-BM demonstrates superior inhibition of the competitive hydrogen evolution reaction (HER) in the liquid phase. These results not only demonstrate the great potential of SACs for direct reduction of CO2 to C1 and C2, but also help in rationally designing high-performance SACs.

3.
Mikrochim Acta ; 187(11): 606, 2020 10 14.
Artículo en Inglés | MEDLINE | ID: mdl-33052480

RESUMEN

An efficient method is reported to prepare endoplasmic reticulum-targetable dual-metallic gold-silver nanoclusters, denoted as ER-Au/Ag nanoclusters (NCs), by virtue of a rationally designed molecular ligand. The prepared ER-Au/Ag NCs possesses red-emitting fluorescence with a strong emission at 622 nm and a high fluorescence quantum yield of 5.1%, which could avoid the influence of biological auto-fluorescence. Further investigation results showed that ER-Au/Ag NCs exhibited superior photostability, minimal cytotoxicity, and ER-targeting capability. Enabled by these meritorious features, ER-Au/Ag NCs have been successfully employed for long-term bioimaging of ER in living cells.Graphical abstract A sensitive non-enzymatic fluorescent glucose probe-based ZnO nanorod decorated with Au nanoparticles.


Asunto(s)
Retículo Endoplásmico/metabolismo , Colorantes Fluorescentes/química , Nanopartículas del Metal/química , Animales , Fluorescencia , Oro/química , Células HeLa , Humanos , Ratones , Microscopía Confocal , Microscopía Fluorescente , Células RAW 264.7 , Plata/química , Sulfonamidas/química , Ácido Tióctico/análogos & derivados
4.
J Colloid Interface Sci ; 665: 443-451, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38537590

RESUMEN

Despite great efforts that have been made, photocatalytic carbon dioxide (CO2) reduction still faces enormous challenges due to the sluggish kinetics or disadvantageous thermodynamics. Herein, cadmium sulfide quantum dots (CdS QDs) were loaded onto carbon, oxygen-doped boron nitride (BN) and encapsulated by titanium carbide (Ti3C2, MXene) layers to construct a ternary composite. The uniform distribution of CdS QDs and the tight interfacial interaction among the three components could be achieved by adjusting the loading amounts of CdS QDs and MXene. The ternary 100MX/CQ/BN sample gave a productive rate of 2.45 and 0.44 µmol g-1 h-1 for carbon monoxide (CO) and methane (CH4), respectively. This CO yield is 1.93 and 6.13 times higher than that of CdS QDs/BN and BN counterparts. The photocatalytic durability of the ternary composite is significantly improved compared with CdS QDs/BN because MXene can protect CdS from photocorrosion. The characterization results demonstrate that the excellent CO2 adsorption and activation capabilities of BN, the visible light absorption of CdS QDs, the good conductivity of MXene and the well-matched energy band alignment jointly promote the photocatalytic performance of the ternary catalyst.

5.
Sci Rep ; 13(1): 1406, 2023 01 25.
Artículo en Inglés | MEDLINE | ID: mdl-36697486

RESUMEN

This study aims to examine visual search strategies of skilled basketball players in an anticipation task. This study selected 48 experienced and inexperienced basketball players. The participants were grouped into novice and expert groups based on their experience. The participants were asked to look at series of pictures of offensive patterns of play in a basketball game from a third person perspective and chose one of the three options: passing, shooting and break through. This study measured and recorded the response time, key pressing results, and eye movements. Eye movement data were recorded using the Tobii X-3 120 eye tracker. The results showed that, the expert group demonstrated superior anticipation performance, and were more accuracy. In addition, the results showed that participants in the expert group and faster predicted the offensive way faster than the novice group. The results also showed that experienced basketball players employed a simple and efficient visual search strategy including greater fixation counts and longer fixation duration on more informative areas than the novice group. Furthermore, the visualization metrics showed that the expert group had a more concise fixation trajectory and focused mainly on key information area. Generally, expert players exhibited a more efficient and effective visual search strategy demonstrating better performance on anticipation tasks.


Asunto(s)
Baloncesto , Humanos , Baloncesto/fisiología , Movimientos Oculares , Tiempo de Reacción
6.
Front Psychol ; 13: 987672, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36312175

RESUMEN

Simultaneous tracking of the position of the ball and player locations and activities places high demands on visual attention in team ball sport athletes. Owing to their extensive sports training, these athletes may be expected to exhibit visual attention skills superior to non-athletes; however, the results of studies examining this are inconsistent. Thus, the first aim of this study was to assess the impact of participating in a team ball sport on visual attention. There is limited empirical evidence indicating a sex difference in visual attention, and few studies have reported on visual attention in male and female athletes. Thus, the second aim of this study was to determine whether team ball sport experience affected any sex differences in visual attention. In total, 44 highly skilled basketball players-22 men (mean age: 21.86 ± 2.15 years) with a mean (SD) of 8.46 (2.92) years training experience and 22 women (mean age: 21.32 ± 1.58 years) with a mean (SD) of 8.22 (2.44) years of training experience-and 44 non-athletic undergraduate college students-22 men (mean age: 21.62 ± 1.88 years) and 22 women (mean age: 21.55 ± 1.72 years)-were recruited and completed this study. Visual attention was measured by using the multiple object tracking (MOT) task. Skilled basketball players showed superior tracking accuracy to non-athletic college students on the MOT task. A significant sex difference was found only among the non-athletic college students, with better tracking accuracy for men than for women on the MOT task. By contrast, no significant sex difference was observed among the skilled basketball players for tracking accuracy on the MOT task. These findings indicated that team ball sport training may enhance visual attention as assessed by tracking accuracy. Given that the male and female basketball players in this study had similar training experience and game performance demands, long-term team ball sport experience appeared to minimize the sex difference in visual attention found among non-athletic students.

7.
Appl Radiat Isot ; 186: 110260, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-35537299

RESUMEN

The measurement of the 59Co(n,2n)58Co reaction cross section with the neutron energy of 14.8 MeV has been performed by the activation method and relative measurement principle. The 300 kV Cockcroft Walton Accelerator of China Institute of Atomic Energy was used to produce quasi monoenergetic neutron beams by the T(D, n)4He reaction. Two thin 27Al and 93Nb foils were attached to the 59Co target and performed as monitors. After the irradiation, the HPGe detector and the GammaVision software were used to measure the activity of the irradiated samples and record the counts of γ-rays, respectively. Finally, some relevant physical quantities were corrected after comparing the results with experimental data in the EXFOR database and evaluated data in the ENDF database.

8.
J Colloid Interface Sci ; 599: 650-660, 2021 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-33979747

RESUMEN

Steam reforming is an effective measure for biomass tar elimination as well as H2-rich syngas (H2 + CO) production. However, the granular or powdery Ni-based catalysts are prone to deactivation, which is caused by inappropriate mass transfer and clogging of catalyst bed. Herein, monolithic wood carbon (WC) with low-tortuosity microchannels is armed with a carbon-coated mesoporous nickel-silica nanocomposite (Ni-SiO2@C) layer via an evaporation-induced self-assembly and calcination procedure for toluene (tar model compound) steam reforming. The quality of the Ni-SiO2@C layer growing on the surface of WC microchannel is affected by the molar ratios of Si/Ni feed. A uniform thin-layer coverage is obtained on the Ni-15SiO2@C/WC (Si/Ni = 15) catalyst, where highly dispersed Ni nanoparticles (average size of 6.6 nm) with appropriate metal-support interaction and remarkable mechanical strength are achieved. The mass transfer, coke resistance, and hydrothermal stability of the Ni-15SiO2@C/WC catalyst were significantly improved by the multilevel structure assembled from the WC microchannels and the secondary ordered SiO2 mesopores. A stable toluene conversion over 97% with an H2 yield of 135 µmol/min was obtained at 600 °C on the Ni-15SiO2@C/WC catalyst. This work opens a new window for facilely constructing high-performance wood carbon-based monolithic tar reforming catalyst.

9.
J Colloid Interface Sci ; 567: 402-409, 2020 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-32078945

RESUMEN

Mitochondrial oxidative stress is associated with the occurrence and development of a wide range of human diseases. The development of methodologies to alleviate oxidative stress-mediated injury may have therapeutic potential. Herein, we report the design and preparation of triphenylphosphonium-functionalized selenium-doped carbon nanodots (TPP-Se-CDs) that can efficiently scavenging hydroxyl radicals (OH) and superoxide anions (O2-) in mitochondria region. Se-CDs with two-photon blue fluorescence were initially prepared by facile hydrothermal treatment of selenomethionine, followed by the covalent conjugation with TPP. The as-obtained TPP-Se-CDs showed high colloidal stability, strong scavenging abilities towards OH and O2-. Moreover, TPP-Se-CDs exhibited low cytotoxicity and mitochondria targeting ability. Taking advantages of these prominent features, TPP-Se-CDs have been successfully applied to combat H2O2 and phorbol 12-myristate 13-acetate (PMA) induced oxidative stress in mitochondria.


Asunto(s)
Colorantes Fluorescentes/metabolismo , Depuradores de Radicales Libres/metabolismo , Mitocondrias/metabolismo , Compuestos Organofosforados/metabolismo , Selenio/metabolismo , Animales , Carbono/química , Carbono/metabolismo , Carbono/farmacología , Supervivencia Celular/efectos de los fármacos , Colorantes Fluorescentes/química , Colorantes Fluorescentes/farmacología , Depuradores de Radicales Libres/química , Depuradores de Radicales Libres/farmacología , Células HeLa , Humanos , Ratones , Mitocondrias/química , Mitocondrias/efectos de los fármacos , Imagen Óptica , Compuestos Organofosforados/química , Compuestos Organofosforados/farmacología , Estrés Oxidativo , Tamaño de la Partícula , Fotones , Puntos Cuánticos/química , Puntos Cuánticos/metabolismo , Células RAW 264.7 , Selenio/química , Selenio/farmacología , Propiedades de Superficie
10.
Spectrochim Acta A Mol Biomol Spectrosc ; 229: 117992, 2020 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-31935654

RESUMEN

With the development of social society, sleep deprivation has become a serious and common issue. Previous studies documented that there is a correlation between sleep deprivation and oxidative stress. However, the information of sleep deprivation related ROS has rarely been obtained. Also, it has been demonstrated that sleep deprivation can induce endoplasmic reticulum (ER) stress. As such, for a better understanding of sleep deprivation as well as its related diseases, it is important to develop probes with ER-targeting ability for detecting ROS generated in this process. Herein, a novel two-photon fluorescent molecular probe, JX-1, was designed for sensing HClO in live cells and zebrafish. The investigation data showed that in addition to real-time response (about 150 s), the probe also exhibited high sensitivity and selectivity. Moreover, the probe JX-1 demonstrated two-photon fluorescence, low cytotoxicity and ER targeting ability. These prominent properties enabled the utilization of the probe for monitoring exogenous and endogenous HClO in both live cells and zebrafish. Using this useful tool, it was found that sleep deprivation can induce the generation of HClO in zebrafish.


Asunto(s)
Retículo Endoplásmico/metabolismo , Colorantes Fluorescentes/química , Ácido Hipocloroso/análisis , Sondas Moleculares/química , Fotones , Privación de Sueño/metabolismo , Pez Cebra/metabolismo , Animales , Células HeLa , Humanos , Límite de Detección , Imagen Molecular/métodos , Privación de Sueño/fisiopatología
11.
J Hazard Mater ; 341: 168-176, 2018 Jan 05.
Artículo en Inglés | MEDLINE | ID: mdl-28777962

RESUMEN

The wide application and unique properties of graphene oxide (GO) make it to interact with other pollutants and subsequently alter their behavior and toxicity. We evaluated the influences of GO at different concentrations (1 and 5mg/L) on copper (Cu) stress in duckweed (Lemna minor L.) GO below a concentration of 5mg/L showed no adverse effects on L. minor. The addition of Cu above 10µM represented a stress condition, which was evidenced by various parameters such as frond number, percent inhibition of growth rate (Ir), total chlorophyll content, dry weight, superoxide dismutase (SOD), catalase (CAT), and peroxidase (POD). When L. minor was simultaneously exposed to GO and Cu, especially at a GO concentration of 5mg/L and a Cu level above 10µM, the increase of Ir and decrease of chlorophyll content were inhibited, suggesting that the Cu stress was diminished in the presence of GO. The addition of Cu alone, ranging between 5 and 20µM, increased Cu, B, Mn, Fe, Co, and Zn uptake, but decreased P uptake. Our results suggest that GO can lessen Cu stress in L. minor via Cu adsorption, thereby protecting the plants from the damaging effects of high Cu concentrations.


Asunto(s)
Araceae/efectos de los fármacos , Cobre/toxicidad , Grafito/química , Nanoestructuras/química , Óxidos/química , Contaminantes Químicos del Agua/toxicidad , Araceae/crecimiento & desarrollo , Araceae/metabolismo , Catalasa/metabolismo , Clorofila/metabolismo , Cobre/química , Peroxidasa/metabolismo , Superóxido Dismutasa/metabolismo , Contaminantes Químicos del Agua/química
12.
Environ Sci Process Impacts ; 16(3): 567-75, 2014 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-24504343

RESUMEN

This research focused on the nutrient removal and the simultaneous CO2, CH4, and N2O emission rates of various combinations of vertical subsurface flow constructed wetlands (VSFCWs) and earthworm eco-filters (EEs) under different influent C/N ratios in synthetic wastewater. The optimal parameters for nutrient removal were influent C/N ratios of 5 : 1 and 10 : 1 as well as the combination VSFCW-EE. Relatively low values of greenhouse gas (GHG) emission rates measured in situ were obtained at a C/N ratio of 5 : 1. The emission rates of CH4 and N2O were considerably lower than that of CO2. The VSFCW-EE and EE-VSFCW combinations showed similar GHG emission results. The C/N ratio of 5 : 1 and the VSFCW-EE combination exhibited the highest nutrient removal efficiency with the lowest GHG emission rate. Wastewater nutrient removal and GHG emission were both high during summer (June to August) and low during winter (December to February).


Asunto(s)
Contaminantes Atmosféricos/análisis , Carbono/análisis , Monitoreo del Ambiente , Nitrógeno/análisis , Eliminación de Residuos Líquidos/métodos , Aguas Residuales/química , Humedales , Animales , Dióxido de Carbono/análisis , Metano/análisis , Dióxido de Nitrógeno/análisis , Oligoquetos
13.
J Environ Health Sci Eng ; 11(1): 8, 2013 Jun 13.
Artículo en Inglés | MEDLINE | ID: mdl-24499586

RESUMEN

The high-strength wastewater is now well known as a threat to the natural water since it is highly possible to arouse water eutrophication or algal blooms. The effects of various light emitting diode wavelengths and intensities on the microalgae biological wastewater treatment system was studied in this research. The various nutrient removals and economic efficiencies represented similar variation trends, and these variations under both high C and N loading treatments were similar too. The order for microalgae C. vulgaris reproduction in terms of dry weight and nutrient removal efficiency both were red > white > yellow > blue, under high carbon and nitrogen loading treatments, indicating that the red light was the optimum light wavelength. Furthermore, considering the optimal light intensity in terms of nutrient removal efficiency was 2500 and 2000 µmol/m2•s, while in terms of economic efficiency was 1000, 1500 and 2000 µmol/m2•s. Therefore, the optimum light intensity was found to be 2000 µmol/m2•s. In addition, the optimal experimental illumination time was determined as 120 h. The Chlorella vulgaris microalgae biological wastewater treatment system utilized in this research was able to purify the high-strength carbon and nitrogen wastewater effectively under optimum light wavelength and intensity.

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