摘要：透射X射线显微镜(transmission X-ray microscope,TXM)是高精密度的尖端X射线成像设备,是现代科学技术的结晶,可以在纳米尺度上进行无损成像,为物理学、生命科学、材料学和化学等领域的众多科学问题提供了有力的研究工具.虽然国内外很多同步辐射装置都建立了以TXM为核心的纳米CT实验站,但是目前国际上只有个别企业能提供商业化的实验室TXM.究其原因,主要是该仪器涉及众多高难度的工程技术问题,诸如:高亮度实验室X射线源、高分辨率X射线光学元器件、高精度样品台、高灵敏度探测器、仪器对温度和振动等环境因素的超高要求等.为了提高研发高端X射线成像仪器的水平,需要逐个突破在研发X射线纳米CT过程中遇到的技术瓶颈.本文主要讨论了工作能量为5.4 keV的实验室TXM的仪器设计,以及全场成像实验结果.该仪器工作在吸收衬度模式下,成像视野达到了26μm,可以对30 nm线宽的特征结构实现清晰的成像,西门子星测试卡的功率谱曲线表明该仪器具有分辨半周期为28.6 nm线对结构的潜力.

摘要：Although significant progress has been achieved in developing high energy aqueous zinc ion hybrid supercapacitors(ZHSCs),the sluggish diffusion of zinc ion(Zn^(2+))and unsatisfactory cathodes still hinder their energy density and cycling life *** work demonstrates the use of nitrogen-doped mesoporous carbon nanospheres(NMCSs)with appropriately hierarchical pore distribution and enhanced zinc ion storage capability for efficient Zn^(2+)*** asprepared aqueous ZHSC delivers a significant specific capacity of 157.8 mA h g^(-1),a maximum energy density of 126.2 W h kg^(-1) at 0.2 A g^(-1),and an ultra-high power density of 39.9 kW kg^(-1) with a quick charge time of 5.5 ***,the ZHSC demonstrates an ultra-long cycling life span of 50,000 cycles with an exciting capacity retention of 96.2%.More interestingly,a new type of planar ZHSC is fabricated with outstanding low-temperature electrochemical performance,landmark volumetric energy density of 31.6 mW h cm^(-3),and excellent serial and parallel *** investigation verifies that the superior electrochemical capability is due to the synergistic effect of cation and anion adsorption,as well as the reversible chemical adsorption of *** work provides not only an innovative strategy to construct and develop novel high-performance ZHSCs,but also a deeper understanding of the electrochemical characteristics of ZHSCs.