现代核分析技术在生命科学中的应用

本文叙述了近几年来现代核分析技术中,中子活化分析,同步辐射X射线荧光分析,扫描质子微探针,质子激发X射线荧光分析和扫描隧道显微技术的发展及其在生命科学研究中的应用。     

Synchrotron radiation applied to the microscopical examination of solid state and biological materials in the X-ray region

The paper describes the properties of synchrotron radiation and makes some comparison with other X-ray sources. The use of synchrotron radiation for various types of X-ray imaging is discussed with reference to specific examples drawn from work carried out recently at the SERC Daresbury Laboratory.     

软X射线光学技术的某些进展

本文主要介绍软X射线等离子体光源、多层膜软X射线反射镜和软X射线显微镜。高强度的实验室用软X射线等离子体光源较之同步辐射具有体积小、造价低、光束大和单位脉冲光通量高等优点。最近发展的多层镀膜用于软X射线正入射光学元件,可以得到比掠入射光学元件好得多的分辨率。软X射线显微镜提供了生物样品分析的一种新工具,它填补了常用的光学显微镜和电子显微镜之间的空隙。     

长春光机所软X射线成像望远镜和同步辐射光束线研制技术的发展现状

本文概述了我所12年(1978～1990)来在软X射线成像望远镜和同步辐射光束线以及短波段光学中有关单元技术研究的发展现状。指出了限制软X射线光学技术发展的主要问题,提出发展软X射线成像和同步辐射反射光学技术应开展的主要研究工作。     

用热解石墨晶体作色散和聚焦光学元件的激光等离子体源的超快X射线光谱仪

由于激光等离子X射线源的光子通量显著低于同步辐射源的光子通量且射线为所有方向的各向同性辐射,所以,很需要具有大的集光立体角和高的积分反射率的光学元件,用热解石墨(PG)晶体作色散和聚焦元件可满足上述要求。由于PG晶体为嵌镶结构,所以可给出很高的积分反射率,而PG薄膜还可安装在任意形状的模具上构成任意形状的光学元件。此外,特殊形状的嵌镶聚焦使这些晶体甚至在弯曲的情况下,也可作为高分辨率X射线光学元件。基于上述元件特性,可以设计出有高集光效率的色散光学元件,用于激光等离子体源超快X射线光谱检测。文中描述了PG弯晶在一台改型的von HAMOS光谱仪中的应用,使用这台光谱仪,测量了飞秒激光器产生等离子体发射的X射线的光谱分布。讨论了产生的X射线在时间分辨扩展X射线吸收精细结构(EXAFS)分析中的应用。实验表明,通过优化晶体特性和光谱仪几何设置,可以实现对过渡金属K边的高分辨率EXAFS测量。     

同步辐射X射线光刻掩模镀金工艺的研究

介绍了利用北京正负对撞机(BEPC)同步辐射X射线光刻装置,进行LIGA工艺技术深结构光刻实验研究,详细论述了X射线光刻使用的掩模制备过程及掩模镀金工艺,在国内最早曝光出直径为400μm、厚为27～45μm的三维立体齿轮胶图形。     

An automatic control system of the synchrotron station and special features of the experiment automation at the LANGMUIR station of the synchrotron radiation source of the RRC Kurchatov Institute

A universal software-hardware architecture of the automatic control system (ACS) of the X-ray experiment for synchrotron stations is designed. The designed ACS ensures the reliable long-time control of the station equipment from remote terminals located in safety zones. A hierarchical three-level architecture of the control system based on personal industrial computers and specialized microcontrollers is selected to realize the hardware part. Data channels are based on Ethernet, RS-485, and RS-232 interfaces. The ACS software embodies the functional-modular principle and contains monitor modules with parametric adjustment, group control modules of functional station blocks, and modules for individual control of mechanisms. Data exchange between the modules is supported by TCP/IP, DCON, and other standard communication protocols. When the control system was being designed, the possibility of expanding the system by embedding bought articles from leading manufacturers was without fail taken into account. The designed system allows its integration with automated experiment control systems. The work presents details of the designed ACS realization on the LANGMUIR multipurpose research technological system of the synchrotron radiation source of the Russian Research Centre (RRC) Kurchatov Institute, the Russian synchrotron station intended for studying interfaces of various nature by using a wide spectrum of precision surface-sensitive and spectrum-selective X-ray technologies, in particular, for studying organic and bioorganic nanosystems on liquid surfaces and various planar nanostructures on solid substrates. The specific character of the LANGMUIR station invited development of a unique software-hardware module for controlling optical elements deflecting the beam from the horizontal line (beam control module), and creation of a special software unit for integrating the fluorescence signal recording section into the ACS and synchronization of the X-ray and fluorescence sections.     

X射线辐射测量

在过去的几年里,人们使用同步辐射技术在X射线波段实现了基于辐射源和基于探测器的辐射测量,电子储存环被用作主辐射源标准,而低温辐射计(ESR)被用作主探测器标准。因为低温辐射计需要强的单色辐射,所以,这种方式也必须使用同步辐射。文中对能量色散探测器和硅光电二极管的探测效率和响应度做了校准,其相对不确定度约1%,所得结果与模型计算值做了比较。     

Development,production, and investigation of PMMA-based X-ray compound refractive lenses

Equipment and technology for producing X-ray refractive lenses from polymethyl methacrylate are described. Each single lens has a spherical profile with a radius of 2.38 mm. A compound lens is composed of 235 single lenses. The focal length of the compound lens for 14-keV X-ray photons is 4.8 m. The lenses developed thereby have been tested on the synchrotron radiation source of the Scientific and Engineering Complex at the Kurchatov Centre of Synchrotron Radiation and Nanotechnologies. The advantages and the drawbacks of the parabolic and spherical lenses are discussed.     

Infrared synchrotron radiation from bending magnet and edge radiation sources for the study of orientation and conformation in anisotropic materials

Over the last decade the use of synchrotron infrared microspectroscopy to spatially discriminate chemical and structural features in many different types of materials has grown considerably and has made significant impact in numerous research areas, in particular, in biological sciences and medicine. Although the brightness advantage of the synchrotron infrared (IR) source is well accepted as the key to high spatial discrimination, little attention has been given to measure the polarization properties of the synchrotron light at the sample stage in IR microscopy. In this work the intrinsic polarization of the IR source and its consequences for the study of anisotropic materials are discussed. The polarization characteristics of predominantly bending magnet radiation and predominantly edge radiation sources were measured at the microscope focus and compared. To illustrate the direct use of the intrinsic polarization of these sources in microscopy, the orientation and conformational details of a drawn polymer sample are considered.     

New progress in X-ray microscopy

Interest has recently revived in microscopy at X-ray wavelengths, stimulated in part by work for microelectronic lithography. The use of synchrotron radiation and other intense sources of X-rays, the development of plastic foils in place of photo-emulsions for recording and the fabrication of Fresnel zone lenses for focusing X-ray beams have all played a part. Some progress has already been made in improving the resolution and contrast of this method of microscopy, in the wavelength range 2–4 nm. The limitation imposed by radiation damage in biological specimens still has to be explored.     

软X射线衍射元件

本文介绍了用于软X射线波段的衍射元件-高精度波带片和金透射光栅的研制技术,国内外研究现状和发展趋势。     

同步辐射软X射线多层膜反射率计的设计

分析了同步辐射软X射线多层膜反射率计;介绍了单色器系统、反射率计系统、真空系统以及双重二倍角机构的设计要点。     

同步辐射X射线双晶单色器联动机构

提出了一种实现固定空间输出位置同步辐射双晶单色器的方法及联动机构。分析了基于Bragg衍射原理的此类X射线双晶单色器发展状况,尤其是在能量扫描过程中,通过运动补偿实现出射光束方向与位置固定的方法,总结了各种机械联动机构。在综合凸轮耦合运动机构及直角联动机构运动特点基础上,详细描述了国家同步辐射实验室成功研制的X射线双晶单色器L型联动机构特征,其融合了二者的优点,简化了结构与运动,重点分析了其结构原理与运动关系,以及机构运动的实现与第二晶体自身微调,并对其性能做了进一步的讨论。测试结果表明,L型联动机构完全适用于实现3.1~12.4 keV整个能量范围的全谱扫描实验研究。     

X-ray microscopy: experimental results with the Göttingen X-ray microscope at the electron storage ring BESSY in Berlin

An X-ray microscope and X-ray microscopy experiments with biological specimens are described. The experiments have been performed with a resolution of about 0.05 μm using the synchrotron radiation of the electron storage ring BESSY.     

窄光谱带宽X射线刻蚀多层膜光栅

结合X射线荧光分析和同步辐射单色器对窄光谱带宽多层膜的需求,开展了窄光谱带宽刻蚀多层膜光栅的理论和实验研究.用平均密度法从理论上阐明将多层膜刻蚀成不同刻蚀比的多层膜光栅后,光谱分辨率将得到提高.用磁控溅射方法制备了W/C多层膜,并用常规的光刻工艺对其进行刻蚀,得到了刻蚀后的多层膜光栅.掠入射X射线衍射测量表明,刻蚀后多层膜的衍射峰位置向小角方向移动,多层膜光栅没有改变剩余多层膜的结构,而且带宽减小,光谱分辨率得到提高,说明实验采用的工艺方法和工艺路线可以满足制作窄光谱带宽刻蚀多层膜光栅的要求,为今后进一步研究实用化元件打下了基础.     

同步辐射软X射线多层膜反射率计测量控制系统

本文介绍我们首先使用一块软X射线多层膜反射镜作为色散元件而研制的同步辐射软X射线反射率计的软硬件结构、功能与特点,并报告了实测结果。     

同步辐射高分辨率衍射光束线的设计

介绍了第三代同步辐射高分辨率X射线衍射光束线的总体设计。给出了高分辨率衍射的基本原理并描述了获得确定光子能量的近平行高强度X射线光束线所必需的光学元件。特别是用X射线动力学理论,解释了双晶及四次反射晶体单色器。作为一个实例,介绍了将于2009年开始在德国汉堡运行的一个新的同步辐射源PETRAⅢ的高分辨率衍射(HighRes)光束线的设置情况。通过优化光学部件,对微米尺寸光束,q空间的分辨减小到Δq=10^-5 nm^-1,光通量大于10¹¹ cts/s。     

Use of synchrotron radiation for the measurement of fluorescence lifetimes with subpicosecond resolution

A method for the measurement of fluorescence lifetimes with subpicosecond resolution is described. The temporal resolution is achieved by using the high harmonic content of the synchrotron radiation produced by an electron storage ring.