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Highlights: Metallic nanoparticles with excellent size controllability and high loading rate are obtained via ultrafast high temperature shock method. The Bi/CNRs-15 electrode exhibits an unprecedented rate performance (237.9 mAh g−1 at 2 A g−1) at − 60 °C, while the energy density of the full cell can reach to 181.9 Wh kg−1 at − 40 °C. A novel strategy of high-rate activation is proposed to obtain high capacity and superior stability at low temperature by creating new active sites for interfacial reaction. Sodium-ion batteries have emerged as competitive substitutes for low-temperature applications due to severe capacity loss and safety concerns of lithium-ion batteries at − 20 °C or lower. However, the key capability of ultrafast charging at ultralow temperature for SIBs is rarely reported. Herein, a hybrid of Bi nanoparticles embedded in carbon nanorods is demonstrated as an ideal material to address this issue, which is synthesized via a high temperature shock method. Such a hybrid shows an unprecedented rate performance (237.9 mAh g−1 at 2 A g−1) at − 60 °C, outperforming all reported SIB anode materials. Coupled with a Na3V2(PO4)3 cathode, the energy density of the full cell can reach to 181.9 Wh kg−1 at − 40 °C. Based on this work, a novel strategy of high-rate activation is proposed to enhance performances of Bi-based materials in cryogenic conditions by creating new active sites for interfacial reaction under large current. [ABSTRACT FROM AUTHOR]

Background: Medical schools prepare undergraduates for clinical practice. Clinical competencies build up gradually and continuously. Existing literature suggests that new graduates are often unprepared for independent practice. This study aims to validate a Chinese version of a Preparedness for Hospital Practice Questionnaire (PHPQ) in a Taiwanese undergraduate cohort. Methods: The original eight-domain English version PHPQ was translated into Chinese and back-translated for expert panel discussion. The eight domains encompass interpersonal skills, confidence, collaboration, management, science, prevention, holistic care, and self-directed learning. Reliability and validity were checked by Cronbach's alpha and by confirmatory factor analysis (CFA), respectively. Participants were divided into higher and lower preparedness groups according to PHPQ results, and compared by age, sex, professional identity, and perception of educational environment. Results: A total of 129 undergraduate medical students (55% males) participated in the study. The overall Cronbach's alpha was 0.94. Participants were found to be best prepared in the domain of disease prevention (M = 4.37, SD = 0.68) and least prepared in interpersonal skills (M = 2.68, SD = 0.77). A satisfactory goodness of fit data was yield from CFA with a CMIN/DF of 2.02. Higher levels of preparedness are associated with stronger professional identity (p

Since the facile oxidation of ammonia is one key for its utilization as a zero‐carbon fuel in a direct ammonia fuel cell, developing the ammonia oxidation reaction (AOR) catalysts with cost‐effective and higher activity is urgently required. However, the catalytic activity of AOR is limited by the scaling relationship of the intermediate adsorption. Based on the density functional theory, the N‐modified Co3Mo3C with separated active sites of NH3 dehydrogenation and N−N coupling has been designed and investigated, which is a promising strategy to circumvent the scaling relationship, achieving improved AOR catalytic performance with a lower theoretical overpotential of 0.59 V under fast reaction kinetics condition. The calculation results show that the hollow site (Co−Mo−Mo and Co−Co−Mo) and Co site in N‐modified Co3Mo3C play essential roles in NH3 dehydrogenation and N−N coupling, respectively. This work not only benefits for understanding the mechanism of AOR, but also provides a fundamental guidance for rational design of AOR catalysts. [ABSTRACT FROM AUTHOR]

With the advantage of fast charge transfer, heterojunction engineering is identified as a viable method to reinforce the anodes' sodium storage performance. Also, vacancies can effectively strengthen the Na+ adsorption ability and provide extra active sites for Na+ adsorption. However, their synchronous engineering is rarely reported. Herein, a hybrid of Co0.85Se/WSe2 heterostructure with Se vacancies and N‐doped carbon polyhedron (CoWSe/NCP) has been fabricated for the first time via a hydrothermal and subsequent selenization strategy. Spherical aberration‐corrected transmission electron microscopy confirms the phase interface of the Co0.85Se/WSe2 heterostructure and the existence of Se vacancies. Density functional theory simulations reveal the accelerated charge transfer and enhanced Na+ adsorption ability, which are contributed by the Co0.85Se/WSe2 heterostructure and Se vacancies, respectively. As expected, the CoWSe/NCP anode in sodium‐ion battery achieves outstanding rate capability (339.6 mAh g−1 at 20 A g−1), outperforming almost all Co/W‐based selenides. [ABSTRACT FROM AUTHOR]

Potassium-ion batteries (PIBs) have gained tremendous attention to compete with lithium-ion batteries (LIBs), especially for storing energy on a large scale, due to their dominance in the geographical distribution of K resources and similar energy storage mechanisms. Herein, using an electrospinning method, we synthesized a unique material of carbon nanonecklaces with a high content of N-doping (N-CNN). The N-CNN-700 anode (N-CNN annealed at 700 °C) shows outstanding durability in PIBs, delivering 173 mAh g–1 after 1000 cycles at 1 A g–1. The unique characteristics of ultrahigh pyrrolic/pyridinic-N doping and hollow necklace-like structures account for excellent performance, which can enable fast electrolyte diffusion, increase active sites for K+ insertion, and enhance K+ adsorption ability. This object demonstrates a clever strategy to design a structure for improved energy storage technologies. [ABSTRACT FROM AUTHOR]