88 research outputs found

    High-performance electrochemical CO2 reduction cells based on non-noble metal catalysts

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    The promise and challenge of electrochemical mitigation of CO2 calls for innovations on both catalyst and reactor levels. In this work, enabled by our high-performance and earth-abundant CO2 electroreduction catalyst materials, we developed alkaline microflow electrolytic cells for energy-efficient, selective, fast, and durable CO2 conversion to CO and HCOO-. With a cobalt phthalocyanine-based cathode catalyst, the CO-selective cell starts to operate at a 0.26 V overpotential and reaches a Faradaic efficiency of 94% and a partial current density of 31 mA/cm2 at a 0.56 V overpotential. With a SnO2-based cathode catalyst, the HCOO--selective cell starts to operate at a 0.76 V overpotential and reaches a Faradaic efficiency of 82% and a partial current density of 113 mA/cm2 at a 1.36 V overpotential. In contrast to previous studies, we found that the overpotential reduction from using the alkaline electrolyte is mostly contributed by a pH gradient near the cathode surface

    Field-Assisted Splitting of Pure Water Based on Deep-Sub-Debye-Length Nanogap Electrochemical Cells

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    Owing to the low conductivity of pure water, using an electrolyte is common for achieving efficient water electrolysis. In this paper, we have fundamentally broken through this common sense by using deep-sub-Debye-length nanogap electrochemical cells to achieve efficient electrolysis of pure water (without any added electrolyte) at room temperature. A field-assisted effect resulted from overlapped electrical double layers can greatly enhance water molecules ionization and mass transport, leading to electron-transfer limited reactions. We have named this process “virtual breakdown mechanism” (which is completely different from traditional mechanisms) that couples the two half-reactions together, greatly reducing the energy losses arising from ion transport. This fundamental discovery has been theoretically discussed in this paper and experimentally demonstrated in a group of electrochemical cells with nanogaps between two electrodes down to 37 nm. On the basis of our nanogap electrochemical cells, the electrolysis current density from pure water can be significantly larger than that from 1 mol/L sodium hydroxide solution, indicating the much better performance of pure water splitting as a potential for on-demand clean hydrogen production

    Additional file 2 of LncRNA ZFAS1 protects chondrocytes from IL-1β-induced apoptosis and extracellular matrix degradation via regulating miR-7-5p/FLRT2 axis

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    Additional file 2: Figure S1. lncRNAs expression changes in chondrocytes treated with IL-1β. A–D The expression levels of four lncRNAs were determined by qRT-PCR analysis. The chondrocytes were treated with 10 ng/mL IL-1β for 24 h. **P < 0.01, compared with the control grou

    A counter-flow-based dual-electrolyte protocol for multiple electrochemical applications

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    This paper reports a computational demonstration and analysis of an innovative counter-flow-based microfluidic unit and its upscaling network, which is compatible with previously developed dual-electrolyte protocols and numerous other electrochemical applications. This design consists of multidimensional T-shaped microchannels that allow the effective formation of primary and secondary counter-flow patterns, which are beneficial for both high-performance regenerative H 2 /O 2 redox cells and flow batteries at a low electrolyte flow-rate operation. This novel design demonstrates the potential to achieve high overall energy throughput and reactivity because of the full utilization of all available reaction sites. A computational study on energy and pressure loss mechanism during scale-out is also examined, thereby advancing the realization of an economical electrolyte-recycling scheme

    Prediction of Bubble Size Distribution above the Bubble-Breaking Plate

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    The chord length distribution (CLD) of bubbles in the region above the bubble-breaking plate in the scrubbing–cooling chamber was studied experimentally using a conductivity probe. The predictive correlations of the shape parameters were established by fitting the CLD with a distribution function. The bubble shape was discussed, and the CLD was analytically converted to the size distribution of the direct contact of the probe. The results showed that the CLD has specific right-skewed characteristics, and the Rayleigh distribution has the best-fitting effect on the CLD. The correlation equation of the shape parameter k of the Rayleigh distribution concerning the Fr number, local gas holdup εg, and dimensionless radius r/R was established. The predicted bubble size distributions (BSDs) based on ellipsoids are in good morphological agreement with the experimental size distributions. The relative error between the calculated and experimental values of the gas–liquid interface area was within ±20%, which verified the accuracy of the prediction of the BSD

    Ursolic Acid and Oleanolic Acid Dissolved in Methanol/Acetone + Water Blends: Thermodynamic Solubility, Intermolecular Interactions, and Solvation Behavior

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    With the purpose of qualitative characterization of the electrostatic properties of the acidity and basicity of ursolic acid (UA) and oleanolic acid (OA), quantitative analyses of the molecular surface were employed in this contribution. The −OH and −COOH groups on the molecules of OA and UA took precedence over establishing hydrogen bonds with the solvents acetone/methanol/water. In addition, the intermolecular interactions of OA and UA with acetone/methanol/water were investigated using an independent gradient model based on the Hirshfeld partition of molecular density. In solutions of OA/UA dissolved in methanol/acetone/water, attractive interactions, including the hydrogen-bond force and van der Waals (vdW) force, occur. The shake-flask technique was applied to evaluate the equilibrium solubility of UA and OA in acetone + water and methanol + water at 101.2 kPa and elevated temperatures covering from 278.15 to 323.15 K. Solvent–solvent interactions accounted by the solubility parameter of solutions had a significant domination in the variability of solubility magnitudes. The van’t Hoff–Jouyban–Acree, Apelblat, and Jouyban–Acree models revealed a good correlation for the measured solubility, with a relative mean deviation of no more than 7.73%. The Kirkwood–Buff integral approach was utilized to determine the preferred solvation of UA and OA by solvent species. In both the rich- and intermediate-composition regions of methanol/acetone, UA or OA is preferentially solvated with positive preferential solvation parameters by methanol/acetone

    Data_Sheet_1_The effect of cognitive reappraisal and expression suppression on sadness and the recognition of sad scenes: An event-related potential study.docx

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    Previous studies have found differences in the cognitive and neural mechanisms between cognitive reappraisal and expression suppression in the regulation of various negative emotions and the recognition of regulated stimuli. However, whether these differences are valid for sadness remains unclear. As such, we investigated the effect of cognitive reappraisal and expression suppression on sadness regulation and the recognition of sad scenes adopting event-related potentials (ERPs). Twenty-eight healthy undergraduate and graduate students took part in this study. In the regulation phase, the participants were asked to down-regulation, expressive suppression, or maintain their sad emotion evoked by the sad images, and then to perform an immediately unexpected recognition task involving the regulated images. The behavioral results show that down-regulation reappraisal significantly diminished subjective feelings of sadness, but expressive suppression did not; both strategies impaired the participants’ recognition of sad images, and expressive suppression had a greater damaging effect on the recognition of sad images than down-regulation reappraisal. The ERP results indicate that reappraisal (from 300 ms to 1,500 ms after image onset) and expressive suppression (during 300–600 ms) significantly reduced the late positive potential (LPP) induced by sadness. These findings suggest that down-regulation reappraisal and expression suppression can effectively decrease sadness, and that down-regulation reappraisal (relative to expression suppression) is a more effective regulation strategy for sadness. Both strategies impair the recognition of sad scenes, and expression suppression (compared to down-regulation reappraisal) leads to relatively greater impairment in the recognition of sad scenes.</p
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