同位素质谱仪技术进展

本文首先回顾了同位素质谱仪发展历史,分析了同位素质谱仪技术进展的基础,介绍了市售七种现代同位素质谱仪。对当前7种类型同位素质谱仪技术优势产品的基本构件和特点进行了描述,讨论了影响同位素质谱仪性能,诸如灵敏度、丰度灵敏度、精密度和分辨率的重要技术进展,给出了仪器性能参数。对不同的同位素质谱仪在各个应用领域的技术优势进行了简要说明。文后,展望了同位素质谱仪的发展趋势。     

质谱仪的配电与接地

质谱仪配电与接地的好坏直接关系到质谱仪的正常运行与寿命。本文总结多种质谱仪的用电与接地需求,并结合本实验室多种大型质谱仪的配电与接地实践,介绍几种实践中已经应用的质谱仪配电方案、相关经验和接地技术。     

高温气冷堆及其乏燃料中核素的质谱分析技术

质谱技术发展初期主要用于与核工业相关的无机同位素丰度的测定,随着核工业的兴起与发展,质谱技术被广泛应用于核燃料与核材料中杂质分析、核燃料燃耗测定以及核素分析等领域。本工作从质谱技术用于高温气冷堆运行中产生的氚检测、乏燃料中痕量钚（Pu）和镎（Np）测定以及乏燃料中¹⁴C测定的原理及应用、研究方法的优缺点三方面展开论述,阐述了用于高温气冷堆及其乏燃料中核素分析方面的气体同位素质谱仪（GIMS）、电感耦合等离子体质谱仪（ICP-MS）、激光共振电离质谱仪（LRIMS）以及加速器质谱仪（AMS）的研制及应用现状,分析了仪器本身及其应用方面存在的问题及发展趋势,讨论了未来相关质谱技术的发展方向,并提出可能的解决方案。为了使质谱技术能够更加有效地应用于高温气冷堆的研究,迫切需要发展体积小、结构简单、便于操作的智能化仪器。     

多传感影像数据融合研究综述

针对多传感影像数据融合技术的发展,对现有应用最广的多传感影像数据融合算法进行了较系统的分析和总结,并对影像融合的评价方法进行了归纳,并在此基础上．对影像融合技术今后的发展作了简要分析。     

微型化质谱仪研究进展

质谱仪具有高效、准确、快速分析的独特优势,在众多领域得到了广泛的认可和应用。其中,质谱仪小型化的发展极大拓展了质谱的适用环境和场景,成为质谱研究的一个重要方向。由于离子阱分析器具有较高性能且易小型化的优势,多被小型化质谱仪所采用。本文总结了近期离子阱质谱仪微型化的研究进展,主要是本实验室近五年的微型质谱仪研发进展,主要从理论、仿真和硬件系统进行介绍,并对小型质谱仪的未来发展方向进行展望。     

MEMS质谱仪研究综述

近年来,小体积、低功耗、价格低廉、使用方便的MEMS质谱仪成为了质谱领域的研究重点和热点。目前国外对MEMS质谱仪及其相关技术的研究已取得了一些成果,甚至研发出了较为完整MEMS质谱仪。但是整体而言,MEMS质谱仪的性能还很低,其研究主要还处于对其元件分别进行微型化的阶段。其中,MEMS离子源以对电喷雾离子源的研究为主;MEMS质量分析器以对离子阱的研究为主;MEMS离子检测器以对法拉第筒的研究为主。本文总结了MEMS质谱仪的最新成果,同时分析了可能面临的问题。     

氦泄漏技术在尿素合成塔制造中的应用

结合尿素合成塔的结构和氦质谱仪系统特点，介绍了氦泄漏技术在其制造中的应用；确定了尿素合成塔的氦泄漏试验方法，并对其要点进行了阐述；提出了尿素合成塔检漏判据，保证了尿素合成塔检漏的顺利进行。     

台式离子阱质谱仪串联质谱技术的介绍与应用

串联质谱技术做为分析混合物和分子结构鉴定的重要手段 ,很早以前已在大型质谱仪上得到应用 ,在两个前后串联在一起的质谱 /质谱仪中 ,前级质谱主要用于担任分离工作 ,在样品被电离后 ,它只允许被分析的目标化合物的母代离子碎片通过 ,经过碰撞裂解后 ,由第二级质谱分析裂解后产生的离子碎片。由于上述过程的完成至少需要三个质量分离器串联而成 ,故在大型质谱仪上应用串联质谱技术成本较高 ,而且操作比较复杂 ,从而限制了该技术的广泛应用。随着离子阱质谱仪的发展 ,利用其可实现时间串联的特性 ,即串联质谱的每个阶段在不同时间段进行 ,使…     

浅析“现代”电力设备

文章根据电力电子技术的发展历史,指出电力电子技术是各学科交叉、相互融合的学科;基于交叉融合的发展趋势,提出了现代电力电子技术下电力设备的定义和主要的研究内容：电力器件、控制技术、故障诊断技术。对基于多源信息融合的先进故障诊断技术在现代电力设备中的应用前景进行了描述。     

现场便携质谱技术研究进展

便携化是质谱仪发展的重要方向之一,近年来,在各种质量分析器的小型化尝试,适用于户外分析的直接进样系统和大气压离子源的研究,以及紧凑式真空系统和检测器的制造工艺等方面都取得了不少成绩。在对这些质谱技术的研究进展加以综述的同时,对现场便携式质谱仪在实时检测中的应用及其发展前景进行了总结。     

质谱检测技术及其一些最新进展

质谱作为一种重要的分析技术,被广泛应用于物理、化学、材料学、生物学、医学等领域.质谱技术包括：离子化技术、离子的质量分析技术、离子检测技术.相对于离子化技术和质量分析技术,科研工作者对离子检测技术关注较少,本文拟对离子检测技术近年来取得的进展进行评述,以便引起相关工作者对离子检测技术的重视.     

稀有气体质谱40Ar-39Ar定年分析技术研究进展

稀有气体质谱分析技术是获得高精度40 A r-39 A r定年数据的基本前提.本文对国内外稀有气体质谱分析技术的发展进行了综述,并分析了稀有气体质谱分析技术在40 A r-39 A r应用领域遇到的问题,提高多接收稀有气体质谱仪的灵敏度和分辨率依然是未来推动40 A r-39 A r定年技术进步的重要手段.同时,围绕稀...     

生物质谱技术及其在RNA检测中的应用

生命科学的需求促进质谱技术的发展,现代的质谱技术为生命科学研究提供丰富的检测手段,本文重点介绍生物质谱技术的特点、性能以及质谱技术的进展;及质谱技术在RNA研究领域的方法学,包括核酸的纯化方法、核酸的离子化技术、核酸的分子量检测技术和核酸质谱数据的解析方法及其软件;以及质谱在核酸领域的具体应用,包括质谱在测序、定量、转录后修饰、核酸的指纹识别、蛋白和核酸相互作用等方面的应用。     

基于质谱的核酸指纹识别技术

基因转录是继基因组计划完成后基因功能研究的基本内容。基因转录研究迫切需要有新方法的支持。人们从蛋白的指纹分析技术中得到启发,开发基于质谱分析的核酸指纹识别技术。通过对核酸进行酶解处理,使其核酸片段分子量位于质谱检测的范围内,通过高分辨质谱技术获得所检测酶解核酸片段的分子量列表;利用基因组研究所获得的大量数据,通过计算机技术,模拟产生核酸酶解产物数据库,通过独特的算法以及基于这些算法开发的工具软件,把酶解的核酸质谱数据和虚拟的核酸酶解产物数据库进行比对,以发现和鉴别核酸。随着这一技术的逐渐应用和发展,将来还可能直接建立基于质谱数据的核酸数据库。相信这一技术在转录组研究中将发挥重要作用。     

Time of flight mass spectrometry applied to the liquid chromatographic analysis of pesticides in water and food

Liquid chromatography coupled to mass spectrometry (LC-MS) is an excellent technique to determine trace levels of polar and thermolabile pesticides and their degradation products in complex matrices. LC-MS can be equipped with several mass analyzers, each of which provides unique features capable to identify, quantify, and resolve ambiguities by selecting appropriate ionization and acquisition parameters. We discuss in this review the use of LC coupled to (quadrupole) time-of-flight mass spectrometry (LC-(Q)ToF-MS) to determine the presence of target and non-target pesticides in water and food. This technique is characterized by operating at a resolving power of 10,000 or more. Therefore, it gives accurate masses for both parent and fragment ions and enables the measurement of the elemental formula of a compound achieving compound identification. In addition, the combination of quadrupole-ToF permits tandem mass spectrometry, provides more structural information, and enhances selectivity. The purpose of this article is to provide an overview on the state of art and applicability of liquid chromatography time-of-flight mass spectrometry (LC-ToF-MS), and liquid chromatography quadrupole time-of-flight mass spectrometry (LC-QToF-MS) for the analysis of pesticides in environmental matrices and food. The performance of such techniques is depicted in terms of accurate mass measurement, fragmentation, and selectivity. The final section is devoted to describing the applicability of LC-(Q)ToF-MS to routine analysis of pesticides in food matrices, indicating those operational conditions and criteria used to screen, quantify, and identify target and "suspected" pesticides and their degradation products in water, fruits, and vegetables. The potential and future trends as well as limitations of LC-(Q)ToF-MS for pesticide monitoring are highlighted.     

NanoSIMS imaging of Bacillus spores sectioned by focused ion beam

Preparation and sectioning of bacterial spores by focused ion beam and subsequent high resolution secondary ion mass spectrometry analytical imaging is demonstrated. Scanning transmission electron microscopy mode imaging in a scanning electron microscope is used to show that the internal structure of the bacterial spore can be preserved during focused ion beam sectioning and can be imaged without contrast staining. Ion images of the sections show that the internal elemental distributions of the sectioned spores are preserved. A rapid focused ion beam top‐sectioning method is demonstrated to yield comparable ion images without the need for sample trenching and section lift‐out. The lift‐out and thinning method enable correlated transmission electron microscopy and high resolution secondary ion mass spectrometry analyses. The top‐cutting method is preferable if only secondary ion mass spectrometry analyses are performed because this method is faster and yields more sample material for analysis; depth of useful sample material is ～300 nm for top‐cut sections versus ～100 nm for electron‐transparent sections.     

HPLC/ICP-MS在环境样品的痕量元素形态分析中的应用

综述了高效液相色谱-电感耦合等离子体质谱联用技术（HPLC/ICP-MS）的最新进展和工作特点，介绍了该技术在环境样品分析中的应用概况、接口类型和应用同位素稀释技术进行元素形态分析等。     

Analysis of carbohydrates and glycoconjugates by matrix-assisted laser desorption/ionization mass spectrometry: An update covering the period 1999-2000

This review describes the use of matrix-assisted laser desorption/ionization (MALDI) mass spectrometry for the analysis of carbohydrates and glycoconjugates and continues coverage of the field from the previous review published in 1999 (D. J. Harvey, Matrix-assisted laser desorption/ionization mass spectrometry of carbohydrates, 1999, Mass Spectrom Rev, 18:349-451) for the period 1999-2000. As MALDI mass spectrometry is acquiring the status of a mature technique in this field, there has been a greater emphasis on applications rather than to method development as opposed to the previous review. The present review covers applications to plant-derived carbohydrates, N- and O-linked glycans from glycoproteins, glycated proteins, mucins, glycosaminoglycans, bacterial glycolipids, glycosphingolipids, glycoglycerolipids and related compounds, and glycosides. Applications of MALDI mass spectrometry to the study of enzymes acting on carbohydrates (glycosyltransferases and glycosidases) and to the synthesis of carbohydrates, are also covered.     

基于基质辅助激光解吸-电离质谱的磷脂分析和成像的基质体系与制样方法

由于磷脂在神经传递和生物膜功能方面的重要作用,磷脂分析已成为目前脂质组学研究的热点,而基质辅助激光解吸-电离成像质谱(MALDI-IMS)是磷脂分析和成像的先进技术。针对磷脂特点,优化基质溶液组成并建立合适的基质制样与覆盖方法是最关键的环节。为了建立具有高真空稳定性(稳定存在2h以上)、耐高频率激光辐射、无基质峰干扰、分布均匀且不引起分析物位移、能全面解吸-电离不同结构与浓度的磷脂,并准确表征其空间分布情况的基质体系,不少研究者进行了大量的研究。本工作从基质类型变化出发,综述了近10年来MALDI-IMS用于生物组织磷脂分析和成像的基质体系及制样方法,并对其发展前景进行了展望。     

Mass spectrometry in the diagnosis of thyroid disease and in the study of thyroid hormone metabolism

The importance of thyroid hormones in the regulation of development, growth, and energy metabolism is well known. Over the last decades, mass spectrometry has been extensively used to investigate thyroid hormone metabolism and to discover and characterize new molecules involved in thyroid hormones production, such as thyrotropin-releasing hormone. In the earlier period, the quantification methods, usually based on gas chromatography–mass spectrometry, were complicated and time consuming. They were mainly focused on basic research, and were not suitable for clinical diagnostics on a routine basis. The development of the modern mass spectrometers, mainly coupled to liquid chromatography, enabled simpler sample preparation procedures, and the accurate quantification of thyroid hormones, of their precursors, and of their metabolites in biological fluids, tissues, and cells became feasible. Nowadays, molecules of physiological and pathological interest can be assayed also for diagnostic purposes on a routine basis, and mass spectrometry is slowly entering the clinical laboratory. This review takes stock of the advancements in the field of thyroid metabolism that were carried out with mass spectrometry, with special focus on the use of this technique for the quantification of molecules involved in thyroid diseases.