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1.
半导体硅材料中掺杂元素锗的SRXRF微区分析研究   总被引:4,自引:0,他引:4  
本文研究了同步辐射X射线微荧光分析法对半导体材料硅单晶中掺杂元素Ge的微区分析。利用同步辐射光源的优越性和微区扫描装置获得了清晰的掺杂元素Ge的二维分布图。实验结果表明,同步辐射X射线微荧光分析法对样品无导电性要求,可以成为对半导体材料硅单晶样品准确地进行大面积扫描微区测定的手段。对掺杂元素Ge在硅单晶生长过程中的分布行为和均匀性研究表明,在硅单晶生长的初始阶段由于小平面效应导致了掺杂元素径向分布  相似文献   

2.
由于月壤等地外样品十分珍贵,在实验室研究中优先使用原位、微区、无损的元素分析方法。电子探针元素面扫描是地外样品研究中常用的分析方法之一。该方法可获取样品整体或者感兴趣区域的多种元素分布数据,应用于矿物相识别与含量估算,锆石等定年矿物的快速定位,矿物环带、出溶、反应边结构等特殊岩相和矿物接触关系等分析和研究。本研究中以嫦娥五号月壤、月球陨石、火星陨石研究为例,介绍了目前元素面扫描的应用方法。此外,本文还对比、分析了电子探针面扫描技术与其它面扫描技术的优缺点和适用范围。未来十年,我国将实施一系列月球、火星、小行星等天体采样返回任务。电子探针元素面扫描分析未来将在这些地外样品研究中广泛使用。同时,建议行星科学家围绕所关心的科学问题,合理搭配多种分析方法以实现各种技术优势互补和样品科学价值最大化,服务我国月球与深空探测任务科学产出和行星科学发展。  相似文献   

3.
地质分析的历史发展及当今热点   总被引:10,自引:0,他引:10  
简要回顾了地质分析技术的历史与发展,分析了当代地学研究对地质分析提出的新要求和当前分析科学所能提供的基础条件,评价和展望了现代地质分析的重要领域和热点技术:整体分析,显微分析技术的发展及对气体地球化学分析、现场分析、地质标准物质和“绿色”分析技术的需求。“地质分析”从“岩析分析”走来,并将向涉及更广领域的“天然材料分析”扩展。整体分析、显微分析、有机和无机生化分析将是其3个重要发展方向。  相似文献   

4.
核子微探针在医学和生物学中的应用   总被引:1,自引:1,他引:0  
生命科学中微量元素研究需要发展一种能在细胞水平上测量生物组织中元素分布的仪器或技术,核子微探针的发展使这种研究成为可能。本文简述了核子微探针的最新发展及其在医学、细胞药物学和细胞谱系中的某些应用。  相似文献   

5.
扫描离子电导显微镜(SICM)是一种扫描探针显微技术,通过测定超微玻璃管探针的离子电流,它能够非接触地扫描样品表面,进而研究样品的形貌及性质。SICM具有成像分辨率高、探针易于制备和对被成像物体无损伤等特点,特别适用于研究生理条件下的活体细胞,是一种与扫描电化学显微镜及原子力显微镜互补的扫描探针显微镜技术。SICM能够对软界面及表面,如活细胞表面的显微结构,进行高分辨率成像;并能够与其它技术联用,研究细胞形貌与功能的关系;还能控制沉积特定分子,实现纳米尺度的显微操作与加工。本文对SICM的发展历史、仪器构造、基本原理及应用进行了综述。  相似文献   

6.
张宁  陈蓁蓁  唐波 《分析化学》2006,34(7):1030-1034
荧光显微镜与荧光光谱仪耦合系统可获取显微荧光成像及微区荧光光谱、荧光寿命的测定信息,广泛应用于细胞、组织中蛋白质的结构功能分析,核酸的识别检测,金属离子、自由基的定量测定,以及纳米生物探针的研制等生物分析研究的热点领域。本文引用文献46篇,综述了荧光成像在生物分析中的应用新进展。  相似文献   

7.
罗丹明荧光探针在生化分析中的应用   总被引:1,自引:0,他引:1  
罗丹明荧光探针作为生物学研究中使用最广泛的荧光探针之一,广泛地应用于活体细胞内小分子的检验、生物大分子的分析以及复杂生物体系的研究等方面.罗丹明荧光探针在生化分析中的应用研究融合了分子生物学、分析化学、有机化学等多个学科.是当今化学研究的热点领域.本文综述了近年罗丹明荧光探针在生化分析中的应用进展,并对其未来的发展趋势进行了展望.  相似文献   

8.
扫描电化学微探针的发展及其在局部腐蚀研究中的应用   总被引:1,自引:0,他引:1  
简要概述当前国内外具有空间分辨能力的扫描微探针技术及其在腐蚀研究中的应用,包括扫描微电极技术(SMET)、扫描电化学显微镜(SECM)、原子力显微镜(AFM)、扫描Kelvin探针技术(SKP)等,其中SMET、SECM、SKP及局部交流阻抗技术可直接测定腐蚀电极表面或界面电化学不均一性的分布图像,而原子力显微镜技术则是通过分子间作用力从纳米尺寸测量腐蚀过程表面形貌的变化.文中侧重介绍作者近年先后建立的具有微米空间分辨度的电化学微探针技术,并利用各种扫描探针技术研究金属/溶液界面电化学不均一性及其局部腐蚀过程.研究表明,空间分辨电化学方法的发展及应用,加深了人们对金属表面和金属/溶液界面电化学不均一性,特别是金属局部腐蚀发生、发展及过程机理的认识.  相似文献   

9.
纳米技术与生物技术的融合,使纳米生物技术获得了很多重要的进展.纳米金作为研究较早的一种纳米材料,其在纳米生物探针方面的应用是最近几年较为活跃的研究方向.本文评述了近年来纳米金探针在生物分析中的应用及进展,阐述了纳米金与生物大分子作用的机理,介绍了纳米金探针在核酸分析、免疫分析、单细胞分析和靶向药物载体4个方面应用的最新进展,并对其未来的发展方向进行了展望.  相似文献   

10.
王楠  徐淑坤  王文星 《化学进展》2007,19(2):408-413
纳米技术与生物技术的融合,使纳米生物技术获得了很多重要的进展.纳米金作为研究较早的一种纳米材料,其在纳米生物探针方面的应用是最近几年较为活跃的研究方向.本文评述了近年来纳米金探针在生物分析中的应用及进展,阐述了纳米金与生物大分子作用的机理,介绍了纳米金探针在核酸分析、免疫分析、单细胞分析和靶向药物载体4个方面应用的最新进展,并对其未来的发展方向进行了展望.  相似文献   

11.
PIXE analysis method is applied to archaeometry problems. Advantages and disadvantages are emphasized. Some examples are presented which show the difficulties; especially important heterogeneities of ceramics, old coins and metals restrain from the use of this technique: other analysis systems, less expensive, like electron microprobe or X-ray fluorescence spectrometry, are compared with conventional PIXE method. The importance of proton microprobe is explained.  相似文献   

12.
For the major, minor and trace element analysis of the inorganic compounds of a Ruhr-Saar coal different preparation techniques are investigated with X-ray fluorescence analysis, electron microprobe and classical wet chemical methods minimizing sample weight at standard preparation times and analytical accuracies. Considering accuracy as well as preparation efforts, determinations by electron microprobe on small sample amounts (<50 mg) proved to be superior to the other methods.Abbreviations AAS atomic absorbtion spectrometry - EMA electron microprobe analysis - IC ion chromatography - ISE ion sensitive electrode - PHOT photometry - WCA wet chemical analysis - XRF X-ray fluorescence analysis - LTA low temperature plasma ashing - HTA high temperature ashing - l.o.i. loss on ignition  相似文献   

13.
An ion trap mass analyzer has been attached to an organic secondary ion microprobe. A pressure differential >100 can be maintained between the ion trap and microprobe. The well-focused secondary ion beam can transit a small (2 mm) diameter tube, but gas flow from ion trap to microprobe is impeded. This pressure differential allows the microprobe to retain imaging capability. Ion trap and microprobe data systems are integrated by taking advantage of the highly reproducible periodicity of the ion trap operating in resonant ejection mode and asynchronous signal and data acquisition afforded by commercially available interface cards. Secondary ion mass spectra and images obtained indicate an approximately 10-fold improvement in sensitivity, although preliminary evidence indicates low (<1%) trapping efficiency. Image data acquisition using the ion trap for mass analysis requires at least 10 times as much time compared to using a quadrupole mass filter because the mass-selected instability mode is used for mass analysis, i.e., mass resolution in the ion trap is not continuous as it is in the quadrupole.  相似文献   

14.
NMR spectra of mammalian cells are taken using surface microprobes that are based on microfabricated planar coils. The surface microprobe resembles a miniaturized Petri dish commonly used in biological research. The diameter of the planar coils is 1 mm. Chinese Hamster Ovaries are immobilized in a uniform layer on the microprobe surface or patterned by an ink-jet printer in the centre of the microcoil, where the rf-field of the planar microcoil is most uniform. The acquired NMR spectra show the prevalent metabolites found in mammalian cells. The volumes of the detected samples range from 25 nL to 1 nL (or 50,000 to 1800 cells). With an extended set-up that provides fluid inlets and outlets to the microprobe, the cells can be perfused within the NMR-magnet while constantly taking NMR spectra. Perfusion of the cells opens the way to increased cell viability for long acquisitions or to analysis of the cells' response to environmental change.  相似文献   

15.
Nuclear microprobes have proved to be versatile tools to perform investigations in materials science with a lateral resolution of typically 1 to 10 m. Many of the commonly utilized ion beam assisted analytical techniques, like PIXE (Particle Induced X-Ray Emission), RBS (Rutherford Back Scattering), NRA (Nuclear Reaction Analysis), and Channeling can be applied with a nuclear microprobe. Additionally, there are methods typical for the nuclear microprobe, e.g. STIM (Scanning Transmission Ion Microscopy). The nuclear microprobe used here has been applied successfully to the analysis of geological and biological specimens and is currently being modified by the introduction of a superconducting solenoid as focusing element to allow higher lateral resolution. Especially the analysis and modification of electronic devices will become possible. An overview of the analytical techniques practiced with the nuclear microprobe is given with emphasis on laterally resolved trace element analysis.  相似文献   

16.
17.
Electron micrographs, and micrographs of electron absorption and silver and iodine distribution on the surfaces and cross-sections of silver iodide-based silicone-rubber membranes showing Nernstian electrode response are presented. An electron microprobe analyzer was used. The electrochemical effects of concentrated (0.6 M) potassium iodide solutions and iron(III) hydroxide or iron(III) ions, are described. The phenomena are interpreted on the basis of the results obtained by electrochemical, atomic absorption and electron microprobe analysis.  相似文献   

18.
《Analytical letters》2012,45(11):1021-1028
Abstract

A fusion technique has been developed for whole rock chemical analysis using the electron microprobe. A dilution of one part sample to three parts flux is used which minimizes matrix effects while still enabling trace element analysis. This technique is a major improvement over other techniques which require a dilution of one part sample to at least seven parts flux. The technique described in this paper has been used successfully for the analysis of a large number of different types of rock samples.  相似文献   

19.
Both the techniques mentioned provide molecular weight and structural information, but laser microprobe mass spectrometry (LMMS) also provides greater control over the degree of fragmentation and enhanced sensitivity. In addition, LMMS allows microprobe analysis (i.e., spatial resolution of a few μm2) as well as providing quantitative measurements. The less energetic nature of fast-atom-bombardment mass spectrometry (FAB-MS) makes it more suitable for the analysis of highly labile polar compounds and high-mass biopolymers.  相似文献   

20.
Chemical composition analysis of apatites and their fluid inclusions from Yu'erya granite was carried out by synchrotron radiation X-ray fluorescence (SRXRF) microprobe. The result shows that all these apatite crystals have a similar chemical signature, with Ca, P, Cl, Mn, Fe, K, S, La, Ce, Pr, Nd, Sm, Eu, Gd, Dy, Er, Yb, Lu, Sr, Y, Zr, U, Th, etc. The rare earth elements chondrite-normalized pattern indicates that these apatites are derived from S-type granite. It is shown by the SRXRF analysis that Zn, Cu and Cl are main components of fluid inclusions in apatites. It is the first time that SRXRF analysis is successfully applied in determination of composition of single fluid inclusions in apatite crystals. This technique was proved to be suitable for crystals with homogenously distributing components and thin covering layer would help to determine the composition of fluid inclusions.  相似文献   

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