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The United States Advisory Committee on Immunization Practices (ACIP) recommends vaccination against meningococcal serogroups A, C, W, and Y (MenACWY) for all 11–12-year-olds, with a booster dose for 16-year-olds, and against meningococcal serogroup B (MenB) for 16–23-year-olds under shared clinical decision-making (SCDM). However, uptake of the MenB vaccine and the MenACWY booster dose is low. This study investigated United States physicians' knowledge, attitudes, and practices regarding recommending MenB and MenACWY vaccines to non-high-risk older adolescents and young adults. An online survey was conducted in April–May 2022 among pediatricians, family physicians (FPs), general practitioners (GPs), and internists who had recommended the MenB and/or the MenACWY vaccine(s) to at least one 16–23-year-old in the past year. Among 407 participants, 50% correctly identified MenB as the leading cause of meningococcal disease among adolescents and young adults. Furthermore, 46% of physicians (47% of pediatricians, 40% of FPs and GPs, 53% of internists) answered correctly that MenB vaccination is recommended under SCDM, and 82% of physicians (96% of pediatricians, 70% of FPs and GPs, 65% of internists) answered correctly that MenACWY vaccination is routinely recommended. Among MenB-vaccinators, 78% reported having received some training or other information on implementing SCDM, and 65% rated recommending MenB vaccination as very important. Knowledge gaps, which varied by specialty, were identified regarding meningococcal disease and vaccine recommendations, particularly regarding MenB. Targeted education of physicians may facilitate discussions about MenB vaccination. [ABSTRACT FROM AUTHOR]

Alkaline water electrolyzers (AWEs) holds great promise for large-scale green hydrogen production, but its commercialization is impeded by high electrical energy costs. Improving flow uniformity in AWEs is crucial to reduce energy consumption, necessitating optimized plate structure designs. Regrettably, the quantitative investigation of flow uniformity in electrolyzers is rare, due to the complex flow behavior. As a consequence, the existing designs primarily rely on empirical knowledge, lacking an efficient and systematic design guidance. This study establishes a general plate structure design strategy for commercial AWEs by introducing quantitative criteria for flow uniformity in multi-scale. The strategy comprises four steps: 1) single unit design to improve lateral liquid distribution, 2) evaluation of velocity magnitude discrepancy at horizontal sections, 3) flow behavior prediction by RTD analysis, and 4) validation through performance test. The strategy incorporates three quantitative parameters φ , δ , θ to evaluate the performance in three different levels. Two novel designs, namely, the rhombus and wedge electrolyzers are proposed to demonstrate the design strategy. Additionally, an in-situ electrolysis visualization/performance test platform is developed to vividly depict the gas-liquid flow during electrolysis and validate the effectiveness of our design guidelines. The proposed design guideline provides step-by-step guidance for the plate structure design of future high-performance commercial AWEs. [Display omitted] • A brief plate structure design guideline for commercial AWEs with improved liquid flow uniformity. • Multi-scale quantitative uniformity criteria by defined parameters φ , δ, and θ. • A concise approach to evaluate flow behavior: RTD analysis by CFD-PT method. • Noval designs for improved performance: wedge and rhombus electrolyzers. • Experimental validation: in-situ electrolysis visualization and performance test. [ABSTRACT FROM AUTHOR]

NiFe-based materials are among the most promising alkaline oxygen evolution reaction (OER) catalysts because of their high intrinsic activities and abundance. Although many advanced NiFe-based catalysts have been developed, few exhibit simultaneous high activity, stability, good mass transfer, and cost-effective large-scale preparation. Furthermore, NiFe-based catalysts have rarely been studied in alkaline water electrolyzers (AWE) where the catalysts work under a large current density in an alkaline electrolyte at high temperatures and high concentrations with tight assembly pressure. This study successfully developes robust and highly active NiFe nanocone array (NA) catalysts that exhibit both fast and cost-effective mass production capabilities. Benefiting from the in situ-formed OER-active NiFe layered double hydroxide (LDH) and the superhydrophilic structure-induced fast mass transfer, the optimized NiFe NA sample presentes a low OER overpotential of 269 mV at 500 mA cm−2 in a 30 wt% KOH solution. The NiFe core-NiFe LDH shell structure and metallic bond between NiFe nanocones and the substrate are crucial for enabling the NiFe electrode to maintain a minimal potential increase of only 4% even after 250 h of testing at 500 mA cm−2 in a 30 wt% KOH solution. Moreover, the AWE using NiFe NA anodes and NiMo cathodes (NiFe//NiMo) works stably at 500 mA cm−2 under 80 °C in 30 wt% KOH solution and presents a power energy consumption of 4.0 kWh Nm−3 H 2 , much lower than that of the Ni mesh//Ni mesh counterpart and most commercial AWEs. This study, for the first time, evaluates the performance of NiFe electrodes in AWE and demonstrates their industrial application prospects in alkaline water electrolysis. [Display omitted] • Fast and large-size production using inexpensive raw materials. • Excellent oxygen evolution reaction activity and stability at large current density. • In situ-formed stable NiFe layered double hydroxide (LDH) layer. • Super hydrophilic structure. • Ultra-low cell voltage and power energy consumption in alkaline water electrolyser. [ABSTRACT FROM AUTHOR]

Porous PPS membranes are commonly employed to separate the released gases in conventional alkaline electrolyzers. However, their poor ionic conductivity and high gas permeability bring up the issues of high energy consumption and rapidly raised safety risks when the electrolyzers operate at high-pressure levels. Therefore, it is of great significance to develop alternative membranes with superior conductivity and gas tightness. In this study, we prepared an ultrathin composite membrane with support layer via combination of hot-pressing and phase inversion precipitation techniques. The comprehensive performances of the prepared membranes, commercial PPS fabric and commercial Zirfon membrane were compared. The cell performance of the prepared membranes and commercial membranes at high current density was also evaluated. The ultrathin composite membrane exhibits lower cell voltage and ionic resistance than commercial membranes. With the introduction of support layer, the tensile strength of the prepared ultrathin composite membrane significantly increased by 19 times. • Cell performance of the membranes at high current density was evaluated. • Lower cell voltage and area resistance obtained for ultrathin composite membrane. • Tensile strength of prepared membranes rose sharply with support layer insertion. • Membranes prepared by combination of hot-pressing and phase inversion techniques. [ABSTRACT FROM AUTHOR]

Alkaline water electrolysis (AWE) is promising for large-scale commercial production of green hydrogen, but large overpotential hinders their promotion. To reduce overpotential, the electrolyzers should be designed to improve flow uniformity, thus requiring a quantitative evaluation of flow distribution. However, the corresponding assessment criteria and method are ambiguous. This study establishes a 3D numerical model as well as quantitative parameters to investigate the liquid flow uniformity in a concave-convex bipolar plate (CCBP) electrolyzer. The simulation result is validated by a flow visualization experiment. The simulated velocity field reveals significant non-uniform flow in the CCBP electrolyzer. A uniformity parameter δ was defined to quantify the velocity discrepancy at various horizontal sections. Additionally, residence time distribution (RTD) analysis by CFD coupled particle tracing (CFD-PT) method is applied to evaluate flow behavior inside electrolyzers. The corresponding dimensionless parameter θ can be applied as a criterion for electrolyzer structure design, operation optimization, and scale-up. [Display omitted] • Non-uniform flow discovered in a commercial CCBP electrolyzer by 3D CFD simulation. • Simulation validation: flow visualization experiment. • A defined parameter δ to describe flow uniformity at horizontal sections. • Electrolyzer flow uniformity evaluation/prediction: RTD analysis by CFD-PT method. • Dimensionless time parameter θ : a criterion for electrolyzer structure design, operation optimization, and scale-up. [ABSTRACT FROM AUTHOR]