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The lattice Boltzmann method (LBM) has been widely used in multi-phase fluid mechanics and is known to be more computationally efficient than the traditional method of numerically solving Navier-Stokes and Cahn-Hilliard equations. Electrowetting is an important component of interfacial sciences, in which the liquid-liquid and solid-liquid interfaces are tuned by electrostatics. Modeling electrowetting using the LBM can be categorized into surface and bulk methods. By modifying the surface tension scalar, the surface method easily reproduces the fundamental Young-Lippmann (YL) equation at low voltages but fails to capture contact angle saturation at high voltages. With fully coupled hydrodynamics and electrostatics in the form of spatially dependent matrices, the bulk method can successfully show contact angle saturation, but it is often unable to reproduce the YL equation due to its intrinsic inaccuracies. The inaccuracies are mainly due to the fact that while the hydrodynamics are all described by continuous physical quantities in the framework of diffusive interfaces, the interfacial electrostatics are governed by discontinuous electric fields caused by sheet charge density. In this paper, we show that accurately modeling electrowetting using the LBM is non-trivial. Additional modeling work, especially the treatment of interfacial electric fields, is needed to recover the fundamental YL equation at low voltages and predict contact angle saturation at high voltages, with a systematic model validation over key parameters and applications.
RESUMEN
Developing low-cost and efficient photocatalyst/co-catalyst systems that promote CO2 reduction remains a challenge. In this work, Ag-Ti3C2Tx composites were made using a self-reduction technique, and unique Ag-Ti3C2Tx/ZnO ternary heterojunction structure photocatalysts were created using an electrostatic self-assembly process. The photocatalyst's close-contact heterogeneous interface increases photogenerated carrier migration efficiency. The combination of Ti3C2Tx and Ag improves the adsorption active sites and reaction centers for ZnO, making it a key site for CO2 adsorption and activation. The best photocatalysts had CO and CH4 reduction efficiencies of 11.985 and 0.768 µmol g-1 h-1, respectively. The CO2 conversion was 3.35 times better than that of pure ZnO, which demonstrated remarkable stability even after four cycle trials with no sacrificial agent. Furthermore, in situ diffuse reflectance infrared Fourier transform spectroscopy (in situ DRIFTS) and valence band spectroscopy were utilized to propose the photocatalytic reaction mechanism and electron transfer channels of the Ag-Ti3C2Tx/ZnO system, confirming that CHO* and CO* are the important intermediates in the generation of CH4 and CO. This study introduces a novel method for the development of new and efficient photocatalysts and reveals that Ti3C2Tx MXene is a viable co-catalyst for applications.
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The development of low-cost electrocatalysts with high oxygen evolution reaction (OER) and oxygen reduction reaction (ORR) performance is crucial for devices used to convert and store hydrogen energy. Research on OER and ORR catalysts has attracted a lot of attention. The limited single-functional catalysts can be expanded as bi-functional catalysts to meet the extra requirement of preparing high-performance catalysts. In this study, we prepared Co-ZIF/CNF in which carbon nanofibers uniformly encapsulated Co- nanoparticles by electrospinning and simple pyrolysis. Co-ZIF/CNF contains both CoOx and Co-Ny active sites, showing bifunctional activity for OER and ORR. The optimized catalyst Co-ZIF1.5/10CNF2 has a low OER overpotential of 390 mV, an onset potential of 0.93 V and a half-wave potential of 0.85 V of ORR, exhibiting an outstanding OER and ORR catalytic performance. The catalyst retained 87.53 % of its current after 12 h, showing great stability. This paper provides a new strategy for designing and preparing OER and ORR bifunctional catalysts.
RESUMEN
Online impulsive buying behavior has drawn an increasing amount of attention from researchers and marketers as well; however, little research has explored how cognitive aspect and emotional aspect effect online impulsive buying together. The study examines the role of product involvement (cognitive aspect) and anticipated regret (emotional aspect) on the online impulsive buying behavior of the consumer. The results indicate that consumers who experienced downward anticipated regret showed more online impulsive buying behavior than those who experienced upward anticipated regret. Moreover, anticipated regret moderates the relationship between product involvement and online impulsive buying behavior, for participants who experienced downward anticipated regret showing more online impulsive buying behavior than those who experienced upward anticipated regret in the low product involvement group, but there is no differential between downward and upward anticipated regret in the high involvement product group. These findings suggest that anticipated regret helps consumers make more deliberative online shopping choices. The implications for both future research and online consumers are discussed.
RESUMEN
An efficient, green and reusable catalyst for organic pollutant wastewater treatment has been a subject of intense research in recent decades due to the limitation of current technologies. Cellulose based aerogel composites are considered to be an especially promising candidate for next-generation catalytic material. This project was conducted in order to evaluate the behavior and ability of green and reusable sugarcane bagasse aerogels to remove P-Nitrophesnol from waste-water aqueous. Co-Zeolitic imidazolate framework@ sugarcane bagasse aerogels composite catalysts were successfully prepared via simple in situ synthesis. The structure of hybrid aerogels and their efficient catalyst in peroxymonosulfate (PMS) activation for the degradation of p-nitrophenol (PNP) was investigated. As a result, the hybrid aerogels/PMS system removed 98.5% of PNP (10mg/L) within 60~70 min, while the traditional water treatment technology could not achieve this. In addition, through a free radical capture experiment and electron paramagnetic resonance (EPR), the degradation mechanism of PNP was investigated. Further research found that the hybrid aerogels can effectively activate PMS to produce sulfate (SO4â¢-) and hydroxyl (OH⢠). Both of them contributed to the degradation of PNP, and SO4â¢- plays a crucial role in the degradative process. The most important feature of hybrid aerogels can be easily separated from the solution. The obtained results showed that the outer coating structure of cellulose can stabilize Co-ZIF and reduce the dissolution of cobalt ions under complex reaction conditions. Moreover, the prepared hybrid aerogels exhibit excellent reusability and are environmentally friendly with efficient catalytic efficiency. This work provides a new strategy for bagasse applications and material reusability.