Ultra-homogeneous dense Ag nano layer enables long lifespan solid-state lithium metal batteries

The unstable electrolyte/lithium(Li)anode interface has been one of the key challenges in realizing high energy density solid-state lithium metal batteries(LMBs)applications.Herein,a dense and uniform silver(Ag)nano interlayer with a thickness of∼35 nm is designed accurately by magnetron sputtering technology to optimize the electrolyte/Li anode interface.This Ag nano layer reacts with Li metal anode to in-situ form Li-Ag alloy,thus enhancing the physical interfacial contact,and further improving the interfacial wettability and compatibility.In particular,the Li-Ag alloy is inclined to form AgLi phase proved by cryo-TEM and DFT,effectively preventing SN from continuously“attacking”the Li metal anode due to the lower adsorption of succinonitrile(SN)molecules on AgLi than that of pure Li metal,thereby significantly reinforcing the interfacial stability.Hence,the enhanced physical and chemical stability of electrolyte/Li anode interface promotes the homogeneous deposition of Li^(+)and inhibits the dendrite growth.The Li-symmetric cell maintains stable operation for up to 1700 h and the cycling stability of LiFePO_(4)|SPE|Li full cell is remarkably improved at room temperature(capacity retention rate of 91.9%for 200 cycles).This work opens an effective way for accurate and controllable interface design of long lifespan solid-state LMBs.

Specimen Variation Effects on XRF Analysis by the Monte Carlo Method: Thicknesses, Densities and Particle Sizes

This theoretical study conducted an X-ray fluorescence (XRF) analysis on specimen variation, with emphasis on variations on the thicknesses, density and particle sizes of specimens. The theoretical formula for X-ray fluorescence intensity was derived. These specimen variations were simulated using Monte Carlo Neutron-Particle Transport Code MCNP5. The Cu element X-ray characteristic peak counts were calculated. These variations made a conspicuous impact on the fluorescence intensity X-ray characteristic, in terms of theoretical formulas and calculations. There was a nonlinear relationship between thicknesses and count, except for thin specimens. As the density increased, the count increased in an exponential form for the saturated thick specimens. When the density reached 1 g.cm-3 , the count remained constant. The matrix materials (moisture) could increase the matrix effects. The higher the moisture was, the greater the matrix effect was. Specimen particle size also affects these measurement results. Hence, these specimens must be prepared before measurement. The calculations were consistent with the theoretical formulas.

眼表微环境与泪膜稳态对视觉质量影响的新认识

2020年发布的中国干眼专家共识第一次将眼表微环境的概念新增到了干眼的定义中。强调了泪膜不稳定和眼表微环境失衡在干眼发病机制中的重要地位,并将视功能障碍作为干眼病情发展的重要结局之一。为了加强对新共识的认识,推动相关的基础与临床研究的开展及转化,为广大干眼患者提供更为细致的诊疗建议,专家组于2021年3年26日在江西吉安召开讨论会,对眼表微环境和泪膜稳态这两方面的研究现状及存在的问题进行分析,主要围绕干眼的这两个核心机制的新认识、与视觉质量的关系、临床的评估和治疗手段的建议和未来发展新方向等提出建议和推荐意见。