Unmasking the reactants inhomogeneity in gas diffusion layer and the performances of PEMFC induced by assembly pressure.

The gas diffusion layer (GDL), as the bridge to reactants and electrons in PEMFC, is a carbon-based porous component and would be deformed under compression to induce changes in the distributions of reactants and the corresponding performances of PEMFC; therefore, unmasking the impacts of assembly pressure on the distribution of the reactants in GDL is significant to improve the performance of PEMFC. In the present article, the structural response of GDL to assembly pressure was first studied; the variations in transport properties of GDL and the reactant distributions induced by assembly pressure were then discussed; the impacts on the dynamic performances of PEMFC were finally investigated. From the results, assembly pressure was found to have different effects on the regions of GDL under the rib and channel, significant gaps in GDL porosity and/or GDL permeability existed near the rib/channel transition region to worsen the inhomogeneity of reactants.

Erector spinae plane block for postoperative pain and recovery in hepatectomy: A randomized controlled trial.

Background: The randomized controlled study aimed to examine the efficacy of preoperative ultrasound-guided erector spinae plane (ESP) block combined with ropivacaine in patients undergoing hepatectomy.

Methods: A total of 60 patients were randomized to ESP block group receiving ropivacaine (Group A) and control group (Group B), n = 30 per group. Visual analog scale (VAS) was recorded in both the groups during rest and movement at the various time intervals.