激光共焦显微拉曼光谱与应用

激光共焦显微拉曼光谱是近十年来发展迅速的一种分子光谱学方法。它是由激光器,全息滤光片衍射光栅,ＣＣＤ探测器,显微镜和计算机数据处理系统等主要部件构成的色散型拉曼光谱仪,它的特点是成象快速简便,分辨率高,适于微量分析,在化学化工,材料科学,生物,药物和法庭科学等领域均有广播的应用前景。     

拉曼光谱仪的两种共焦显微术的对比

介绍了拉曼光谱仪采用的共焦显微术的广泛应用；叙述了真共焦显微术的基本原理和优点，以及简单共焦（即“赝共焦”）显微术的主要缺点；列出了有关实验结果及数据对比。     

径向偏振光瞳滤波共焦拉曼光谱显微系统研制

针对共焦拉曼系统空间分辨力提升的迫切需求,研制了一套径向偏振光瞳滤波共焦拉曼光谱显微系统(RPCRS).该系统利用径向偏振光发生器(S波片)将激光器发出的线偏振光转换为径向偏振光;然后,利用光瞳滤波器对径向偏振光进行调制,从而压缩拉曼激发光斑;最后,利用共焦针孔消除焦点外位置的拉曼散射光,进一步提升共焦拉曼显微系统的空...     

显微拉曼光谱技术检验射击残留物的研究

本文介绍了在室温环境下激光显微拉曼光谱分析方法对军用枪射击残留物检验研究的情况,得到了射击残留物的拉曼散射光谱图。该技术具有灵敏度高、分析速度快、检材量小、无需制样等特点,是检验射击残留物非常有效的方法。     

高温拉曼光谱仪

介绍了在原有ＪＯＢＩＮＹ′ＶＯＮＵ１０００型拉曼光谱仪上作的两种改造。一是配备了显微热台,实现了高温达１６２３Ｋ的共焦显微拉曼（Ｍｉｃｒｏ－Ｒａｍａｎ）;二是采用了光谱信号的时间分辨检测技术,实现了可达２０２３Ｋ温度下的宏观拉曼（Ｍａｃｒｏ－Ｒａｍａｎ）。拓展了拉曼光谱研究高温物质结构的应用。     

拉曼光谱成像技术新进展及其应用

拉曼光谱成像技术是拉曼光谱分析技术的新发展,借助于现代共焦显微拉曼光谱仪器以及新型信号探测装置,它把简单的单点分析方式拓展到对一定范围内样品进行综合分析,用图像的方式显示样品的化学成分空间分布、表面物理化学性质等更多信息。本文介绍拉曼光谱成像技术的基本原理和实验方法,并且特别介绍HORIBA Jobin Yvon公司的新型快速拉曼成像技术SWIFT和DuoScan,最后用实验实例说明这些技术的重要应用。     

激光共焦显微光束的偏转扫描

为了提高激光共聚焦系统的扫描速度,本文提出一种逐场扫描的场同步扫描方法。构建了激光共焦显微系统,将美国THORLABS公司的GVS002型二维检流计振镜应用于该系统,根据光学系统参数以及扫描范围要求计算振镜的整场扫描波形。借助NI公司的PCIe6353多功能数据采集卡,输出行同步的扫描波形,同时,对共焦显微系统共焦位置上针孔处的光强信号进行采集,先后扫描一幅256×256和512×512的图像,记录扫描图像和成像时间;然后,在相同的硬件结构下,以场同步的方式输出扫描波形,记录扫描图像和成像时间。实验结果表明：场同步方式扫描256×256图像的速度可提高10倍,扫描512×512图像的速度可提高5倍,且满足共焦显微成像的清晰、抗干扰能力强等要求。与行同步扫描方法相比,场同步扫描方法可以消除行与行之间转换的停留时间,在不改变硬件的情况下大幅提高扫描速度。     

光谱共焦位移传感器镜头设计研究

光谱共焦位移传感器是一种高精度,非接触式位移传感器.本文讨论了光谱共焦法用于位移测量的基本原理,用Zemax光学设计软件完成了一个镜头组的设计,并给出了光谱共焦位移传感器镜头组的设计方法以及像差分析.该镜头组采用密接透镜结构,工作波段为486.13nm -656.27nm,测量范围约为91μm,轴向响应FWHM优于5 μm.通过线性回归分析得出波长与位移间判定系数为0.99523,在测量范围内,位移与波长间的线性关系较好.     

电化学反应过程中黄铜表面的原位显微拉曼光谱分析

利用显微共焦拉曼光谱仪在线分析了在以十二烷基硫酸钠水溶液为电解液、石墨为辅助电极时电化学反应过程中黄铜表面化学成分的变化，进而分析了外加电压引起摩擦因数变化的机理。结果表明：外加电压对摩擦因数的控制主要通过对表面有机离子吸附膜的影响来实现；黄铜表面存在有机离子吸附或反应而形成的边界润滑膜时摩擦因数较低；黄铜表面不存在有机离子润滑膜而存在较多的氢氧根离子时摩擦因数较高；溶液的搅拌对电控摩擦的恢复有较重要的作用。     

激光显微拉曼光谱仪的设计与性能参数测定

激光显微拉曼光谱仪是一种具有较高的空间分辨率,适用于固体定性分析和液体定量分析的微区无损检测系统,综合了光学、机械、电子和计算机等技术。可以快速鉴别各种材料,并且具有成像分辨率高、分析速度快、使用简单等特点。针对这些特点,完成了激光显微拉曼光谱仪的设计和参数测量。首先阐述了激光显微拉曼光谱仪的分析基础,然后介绍了激光显微拉曼光谱仪设计,最后详细说明了对光谱仪的性能参数测定。调试完成的激光显微拉曼光谱仪的重复性和线性度参数均已达到预期的设计,满足固体微区检测和液体定量检测的需要。     

基于激光共焦扫描显微镜方法的磨损表面三维数字化描述

表面形貌的精确描述在许多领域诸如材料、生物医学、摩擦学和机器状态监测等领域变得越来越重要。开发了一种基于激光共焦显微镜和图像处理技术的研究磨损表面及表面参数的新方法。首先用B io-rad Rad iance 2000激光共焦显微镜方法获得精确的三维表面形貌,然后用计算机辅助图像分析技术自动计算出表面特征参数。应用示例表明本文所研究的方法是可靠的,能对工程表面的表面粗糙度特征进行精确描述。     

激光扫描共聚焦显微镜技术的发展及应用

激光扫描共聚焦显微术是先进的分子和细胞生物学研究技术。它在荧光显微镜成像的基础上加装激光扫描装置,结合数据化图像处理技术,采集组织和细胞内荧光标记图像。在亚细胞水平观察钙等离子水平的变化,并结合电生理等技术观察细胞生理活动与细胞形态及运动变化的相互关系。由于它的应用范围较广泛,已成为形态学、分子细胞生物学、神经科学和药理学等研究领域中很重要的研究技术。     

ZnO纳米线的光致发光性及拉曼散射性能

利用物理热蒸发法通过控制载气流量和氧气流量制备出具有倒V字形尖端的ZnO纳米线,利用荧光光谱仪、拉曼光谱仪对ZnO纳米线的光致发光性能和拉曼散射性能进行了测试.结果表明:与其它形状的ZnO纳米线的光致发光性能不同,该ZnO纳米线在423～458 nm区域有二个宽频带强蓝光发射,在527 nm处出现一个非常弱的绿光发射,没有发现紫外光发射;相对于ZnO纳米粉,ZnO纳米线的拉曼光谱峰发生约3 cm-1红移,主要来源于光子限制效应.     

Confocal imaging with bilateral scanning and array detectors

A novel arrangement for confocal microscopy is presented, in which the key elements are the use of an array detector such as a CCD for confocal image collection and the use of one double-sided scanning mirror element for bilaterally scanning the object and collecting the data on the CCD. The resulting arrangement is shown to be capable of confocal imaging with high photon efficiency under adjustable conditions of confocality and varying image acquisition rates, i.e. from slow speed up to real-time imaging. Either laser or conventional light sources may be utilized. In addition to CCD registration, direct observation by eye of the confocal image in fluorescence is also possible.     

Confocal differential interference contrast (DIC) microscopy: including a theoretical analysis of conventional and confocal DIC imaging

A technique for obtaining differential interference contrast (DIC) imaging using a confocal microscope system is examined and its features compared to those of existing confocal differential phase contrast (DPC) techniques as well as to conventional Nomarski DIC. A theoretical treatment of DIC imaging is presented, which takes into account the vignetting effect caused by the finite size of the lens pupils. This facilitates the making of quantitative measurements in DIC and allows the user to identify and select the most appropriate system parameters, such as the bias retardation and lateral shear of the Wollaston prism.     

Chemical and Physical Analysis of Reaction Films Formed by Molybdenum Dialkyl-Dithiocarbamate Friction Modifier Additive Using Raman and Atomic Force Microscopy

In order to improve the fuel economy of engines it is now common to include in modern engine oils small quantities of soluble, molybdenum-based friction-reducing additives. These additives are generally believed to form MoS₂ in rubbed contacts and thereby reduce friction in boundary lubrication conditions. This paper describes the application of Raman and atomic force microscopy to study the reaction films formed in rubbing contacts by simple solutions of molybdenum dialkyl-dithiocarbamate additive. Raman microanalysis shows that MoS₂ is present in the wear scars produced whenever this molybdenum additive effectively reduces friction. In reciprocating friction tests, the MoS₂ is unevenly distributed in the wear scar, with more in the centre of the stroke than at the reversal points. This explains the experimentally observed influence of stroke length on friction. Atomic and lateral force microscopy show that when the additive effectively reduces friction, tiny, discrete, flake-like low friction domains are present in the wear scar. These are typically 10–25 nm in diameter and 1–2 nm thick and are believed to represent MoS₂ nanocrystals as have been previously reported in the literature using high-resolution TEM. Coupled topography and lateral force measurements shows that these nanocrystals are present only on the high spots of the rubbed surface.     

Mapping cholesteryl ester analogue uptake and intracellular flow in Paramecium by confocal fluorescence microscopy

In Paramecium primaurelia the uptake and intracellular flow of cholesteryl ester was studied by fluorescence confocal laser scanning optical microscopy and by the fluorescent analogue cholesteryl‐BODIPY^® FL C₁₂ (BODIPY‐CE). The BODIPY FL fluorophore has the characteristic of emitting green fluorescence, which is red‐shifted as the probe concentrates. In cells incubated with 25 µm BODIPY‐CE for 30 s, fluorescence is found in vesicles located around the cytopharynx in the posterior half of the cell. Successively, the lipid is internalized by food vacuoles, the fluorescent vesicles are distributed throughout the cell and the intracellular membranes are labelled. The food vacuole number is maximum after 10–15 min of continuous labelling, then it decreases until no food vacuoles are found in 30‐min fed cells. BODIPY‐CE accumulates in red‐labelled cytoplasmic droplets located in the anterior half of the cell. When food vacuole formation is inhibited by trifluoperazine, fluorescence is found on cellular membranes and in small green‐labelled vesicles at the apical pole. The inhibition of clathrin‐mediated endocytosis does not interfere in P. primaurelia with BODIPY‐CE intracellular flow: intracellular membranes and storage droplets in the cell anterior part are dyed. Conversely, the use of sterol‐binding drugs prevents the lipid accumulation in droplets, stopping the lipid within the cytoplasmic membranes. Furthermore, the cells treated with monensin and cytochalasin B show a labelling of the cellular membranes and lipid droplets, whereas NH₄Cl reduces the lipid storage. Low temperature (4 °C) does not prevent the internalization of BODIPY‐CE that, however, is localized at the cytoplasmic membrane level and does not accumulate in storage droplets. In addition, BODIPY‐CE inhibits phagocytosis, as evidenced by comparing the kinetics of food vacuole formation of control cells, only fed with latex particles, with that of cells fed with latex particles and BODIPY‐CE. In conclusion, this study points out that in P. primaurelia the cholesteryl ester enters the cell via food vacuoles and through the plasma membrane and, inside the cell, it alters cell functions.     

佰元真假钞光谱和能谱的分析比较

通过傅立叶变换红外光谱仪、显微拉曼光谱仪以及电子探针/能谱仪等分别对真假佰元纸币进行测试,并对测试结果进行比较和分析,从光谱和能谱分析的角度比较真假佰元纸币的异同,为假币的鉴别提供另一种有效的方法。