高分辨率软X射线显微成像原理及其应用

软X射线显微成像具有分辨率高、辐射损伤小以及能够对含水的生物样品直接进行显微成像等独特的优势,目前已成为研究生命科学和生物学等学科中的超微观世界的特殊工具.本文简要介绍基于波带片的高分辨率软X射线显微成像的原理及其应用.     

生物样品的软X射线显微成象

软X射线显微术最适合于自然状态下生物样品的高分辨率成象。在过去十年中软X射线显微成象技术在世界范围内得到了迅速的发展。本文扼要地讨论了软X射线显微成象的衬度机制和高分辨率X射线光学的基本原理,并且综述介绍各种软X射线显微成象方法以及它的发展和前景。     

软X射线显微术及其用于生命科学研究概况

介绍了同步辐射软Ｘ射线显微术的基本原理和基本类型，举例说明了软Ｘ射线接触显微术、扫描显微术、全息显微术、相差显微术以及低温显微术在生命科学研究中的应用情况，简要介绍了国家同步辐射实验室软Ｘ射线显微术实验站的工作．     

同步辐射软X射线接触显微成像

软Ｘ射线显微术适合于自然状态下生物样品的高分辨率显微成像。软Ｘ射线接触显微术是Ｘ射线显微成像方法中最简单也是迄今唯一到接近理论分辨的方法。本文阐述软Ｘ射线接触显微成像的原理和方法，并报告用合理肥步辐射光源进行软Ｘ射线接触显微成像的一些实验结果。     

生物样品的软X射线显微成象

软X射线显微术最适合于自然状态下生物样品的高分辨率成象。在过去十年中软X射线显微成象技术在世界范围内得到了迅速的发展。本文扼要地讨论了软X射线显微成象的衬度机制和高分辨率X射线光学的基本原理,并且综述介绍各种软X射线显微成象方法以及它的发展和前景。     

合肥同步辐射软X射线显微术研究

合肥国家同步辐射实验室首期建设的光束线之一用于软Ｘ射线显微成像研究。实验站现已装置初型的扫描透射Ｘ射线显微镜，并正在进行亲一代的扫描显微建设，同时还使同步辐射光进行接触软Ｘ射线呈微成像研究，并对选取的一些生物样品进行了成像试验。本文介绍了合肥同步辐射光源上软Ｘ射线显微术实验线站的建设及完成的一些实验结果。     

软X射线显微成像位相型波带片浅析

软X射线显微成像技术是研究超微观世界的有力工具,而位相型波带片则以其高分辨率的优势,目前已成为实现软X射线成像的理想光学元件.本文简要介绍位相型波带片的特性及其在软X射线显微成像技术中的应用.     

激光软X射线高速显微技术的现状与发展

软X射线显微技术可使活的生物样品成象。与电子显微镜相比,它具有低的损伤和强的穿透能力,而且分辨率高于光学显微镜。利用“水窗”波段的X射线(0.28-0.53 keV),样品可以在其自然状态下或有培养物的环境下成象。与电子显微镜有关的一些样品准备程序(如固定、脱水、着色等等)都可以避免。它在光学和电子显微镜之间是一个重要的补充。本文阐述了软X射线显微技术的原理、类型和未来的发展。     

氦气环境中湿样品软X射线显微成像研究

介绍了在国家同步辐射实验室软Ｘ射线显微术实验站上利用氦气进行软Ｘ射线显微成像研究的理论依据、实验装置以及实验结果和意义。     

软X射线位相型波带片的初步研究

简述了国内外软X射线波带片的发展及其最新研究成果。根据光波的矢量分析方法，数值模拟计算了入射波长为软X射线显微术中常用的2.3、3.2和4.5nm时，以不同材料制作的位相波带片其衍射效率随材料厚度的变化曲线，初步确定出适于制作位相波带片的几种材料。简要介绍了拟采取的制作软X射线位相波带片的方法。     

Soft X-ray photoelectron spectroscopy of compound semiconductor surfaces and interfaces

Photoelectron spectroscopy is one of the leading techniques in the study of solid surfaces. In particular, X-ray photoelectron spectroscopy (XPS) — also known as ESCA (electron spectroscopy for chemical analysis) — is extensively used in materials science. This paper discusses the advantages of coupling the soft X-ray continuum of synchrotron radiation with this technique (SXPS). The primary advantage of high surface sensitivity is illustrated with case studies of clean semiconductor surfaces and of the initial stages of formation of metal/semiconductor and semiconductor/semiconductor interfaces. The prospects for soft X-ray photoelectron microscopy are briefly discussed.     

Low-frequency Raman characterization of size-controlled anatase TiO<Subscript>2</Subscript> nanopowders prepared by continuous hydrothermal syntheses

The advantages of a recently presented continuous hydrothermal elaboration route for size-controlled anatase TiO₂ nanoparticles are investigated. Nanopowders prepared by this route and using a soft chemistry route are characterized using X-ray diffraction, surface area measurements, high-resolution electron microscopy and Raman spectroscopy with an emphasis on the determination of the size distribution with low-frequency Raman measurements. The continuous hydrothermal route is shown to be more suitable for producing narrower size distributions.     

Magnetic microstructures and their dynamics studied by X-ray microscopy

Full-field soft X-ray microscopy in combination with X-ray magnetic circular dichroism as contrast mechanism is a powerful technique to image with elemental specificity magnetic nanostructures and multilayered thin films at high lateral resolution down to 15nm by using Fresnel zone plates as X-ray optical elements. Magnetization reversal phenomena on a microscopic level are studied by recording the images in varying external magnetic fields. Local spin dynamics at a time resolution below 100ps can be addressed by engaging a stroboscopic pump-and-probe scheme taking into account the time pattern of synchrotron storage rings. Characteristic features of magnetic soft X-ray microscopy are reviewed and an outlook into future perspectives with regard to increased lateral and temporal resolution is given.     

激光软X—射线近贴显微技术初步研究

描述了用高功率脉冲激光打靶产生的等离子体作为软X-射线源而进行的近贴显微研究,并得到了分辨率好于1μm的结果.     

A pulse-train laser driven XUV source for picosecond pump–probe experiments in the water window

We describe the development of a table top soft X-ray source based on a laser produced plasma. The plasma is produced by a Nd:YLF pulse-train laser which delivers pulse trains of up to 400 pulses each of about 25 ps duration. Number and energy of the micropulses are fully computer controlled adjustable for an optimum interaction with a rotating solid target. Spectral, spatial and temporal characteristics of the X-ray emission from Mylar and copper targets have been studied. A calibrated back-illuminated CCD camera together with a slit grating spectrograph were utilized for the measurement of the absolute soft X-ray photon fluxes. The temporal measurements were performed using a streak camera while the plasma size was measured with a zone plate. An application of the system in a X-ray absorption experiment is shown. The advantages of the system in view of possible optical pump and soft X-ray probe experiments will be discussed.