红外磁光光谱实验原理和技术（续一）

本文简要地介绍了有关磁光光谱学的发展情况；详细说明了超导磁体、傅里叶变换红外光谱仪、红外激光器、样品架等红外磁光光谱实验系统中几种关键仪器设备的工作原理、结构、性能、使用方法；对现代最常用的傅里叶变换红外磁光光谱和红外激光磁光光谱两种实验系统的特点、功能作了分析、比较。     

热重分析中逸出气体的傅里叶变换红外光谱测量

随着傅里叶变换红外光谱技术的迅速发展,一些新的联用技术不断涌现并日趋成熟。本文旨在介绍热重分析-傅里叶变换红外光谱(TGA-FTIR)的联机方法、数据处理及结果表示,并以几个实例说明其应用。     

二维红外相关光谱在两面针与单面针鉴别中的应用

利用傅里叶变换红外光谱法及二维红外相关光谱法对两面针与单面针进行研究,探讨其一维、二维红外光谱特征及其差异,为快速鉴定两面针样品提供依据。两面针与单面针均为芸香科花椒属木本植物,均可入药,2者外形极为相似,药材市场常用靡价的单面针制成饮片冒充两面针。本实验结果表明:两面针与单面针的一维红外光谱差别甚小,但通过二阶导数光谱结合二维傅里叶红外光谱的方法可以将2者完全区分开采。本方法快速、廉价、有效,对两面针的鉴别提供一种新的方法和技术。     

红外磁光光谱实验原理和技术

本文简要地介绍了有关磁光光谱学的发展情况；详细说明了超导磁体、博里叶变换红外光谱仪、红外激光器、样品荣等红外磁光光谱实验系统中几种关键仪器设备的工作原理、结构、性能、使用方法；对现代最常用的傅里叶变换红外磁光光谱和红外激光磁光光谱两种实验系统的特点、功能作了分析、比较。     

DAC/FTIR和GC/FTIR联用技术鉴定爆炸残留物

来自爆炸现场的爆炸残留物样品一般呈微粒状。利用配置高压金刚石池(AC)的傅里叶变换红外光谱仪(DAC/FTIR)可以检验小至1微克重的炸药微粒,测试样品在高压条件下,其红外吸收频率会向高波数位移。利用大口径熔融石英毛细管柱气相色谱与傅里叶变换红外光谱联用技术(GC/FTIR)可以分离、鉴定炸药混合物和现场提取的爆炸残留物。     

傅里叶变换红外光谱法在高分子材料研究中的应用

傅里叶红外光谱仪具有测试速度快、样品无损、检测灵敏等优点,目前在高分子材料的鉴别、聚合反应研究等领域得到广泛应用。本文介绍了红外光谱的基本原理及其在高分子材料研究中的应用,并采用傅里叶变换红外光谱仪对5类高分子材料进行了鉴别。     

傅里叶变换红外光谱仪器技术和应用

目前博里叶变换红外光谱法已成为最有用的分析手段之一。本文简要介绍了傅里叶变换红外光谱原理，仪器，以及近红外，远红外，发射，反射，光声，显微，基体隔离，联用技术，傅里叶变换喇曼等光谱技术和应用。     

光导纤维在傅里叶变换红外及拉曼光谱中的发展及应用

本文简要介绍了光导纤维传输光的基本原理,总结了近红外和中红外波长范围的光导纤维的实际应用状况及其近年来光导纤维材料的发展与改进,并对光导纤维在傅里叶变换近红外光谱(FT-NIR)、中红外光谱(FT-MIR)及傅里叶变换拉曼光谱(FT-Raman)中的广泛应用作了综述。     

纳米级红外光谱用于聚合物的表征

尽管红外微光谱有广阔的用途,但是由于光学规则与实际设计的局限性,其基本的空间分辨率受到了限制.傅里叶变换红外光谱的空间分辨率局限于3倍的红外辐射波长.通过使用衰减全反射(ATR)的方式,可以将其空间分辨率接近于其辐射波长.纳米级红外光谱(Nano IR)技术可以解决分辨率的限制,提供一种在200 nm及其之上可以测量样品物理和化学性质的方法.     

衰减全反射红外光谱法在聚合物表面改性的应用

介绍衰减式全反射红外光谱(ATR-FTIR)的基本原理,特点以及在聚合物表面改性方面的应用。衰减全反射光谱是一种内反射光谱,它以光辐射两种介质的界面发生全内反射为基础。与常规透射式傅里叶变换红外光谱(FTIR)相比,傅里叶变换衰减式全反射红外光谱具有制样简单,非破坏性等很多优点。此外,ATR-FTIR常被应用于检测聚合物表面的组成和性质。     

Near-field photothermal microspectroscopy for adult stem-cell identification and characterization

The identification of stem cells in adult tissue is a challenging problem in biomedicine. Currently, stem cells are identified by individual epitopes, which are generally tissue specific. The discovery of a stem-cell marker common to other adult tissue types could open avenues in the development of therapeutic stem-cell strategies. We report the use of the novel technique of Fourier transform infrared near-field photothermal microspectroscopy (FTIR–PTMS) for the characterization of stem cells, transit amplifying (TA) cells and terminally differentiated (TD) cells in the corneal epithelium. Principal component analysis (PCA) data demonstrate excellent discrimination of cell type by spectra. PCA in combination with linear discriminant analysis (PCA–LDA) shows that FTIR–PTMS very effectively discriminates between the three cell populations. Statistically significant differences above the 99% confidence level between IR spectra from stem cells and TA cells suggest that nucleic acid conformational changes are an important component of the differences between spectral data from the two cell types. FTIR–PTMS is a new addition to existing spectroscopy methods based on the concept of interfacing a conventional FTIR spectrometer with an atomic force microscope equipped with a near-field thermal sensing probe. FTIR-PTMS spectroscopy currently has spatial resolution that is similar to that of diffraction-limited optical detection FTIR spectroscopy techniques, but as a near-field probing technique has considerable potential for further improvement. Our work also suggests that FTIR–PTMS is potentially more sensitive than synchrotron radiation FTIR spectroscopy for some applications. Microspectroscopy techniques like FTIR–PTMS provide information about the entire molecular composition of cells, in contrast to epitope recognition that only considers the presence or absence of individual molecules. Our results with FTIR–PTMS on corneal stem cells are promising for the potential development of an IR spectral fingerprint for stem cells.     

铝碳酸镁及其伪品的结构鉴定

采用傅里叶变换红外(FTIR)光谱法和X射线衍射法对4个铝碳酸镁样品进行了结构分析。结果表明,4个样品中,有2个是真品,有2个是伪品。结论:FTIR光谱法和X射线衍射法可快捷、准确地鉴别铝碳酸镁及其伪品。     

FTIR法用于白酒的区分及真伪鉴定

采用傅立叶变换红外光谱(FTIR)法分析研究剑南春、贵州茅台(1#)及假贵州茅台(2#)白酒样品的红外光谱图。结果显示,不同香型白酒的冰冻干燥物在一维谱和二阶导数谱上均具有明显的指纹特征。真、假茅台酒干燥物的一维谱差异明显。该方法简便、快速,可直观的评价白酒产品的品质与真伪。     

野葛与粉葛的二维红外相关光谱鉴别

采用傅立叶变换红外(FTIR)光谱法并结合二维红外相关光谱(Two-dimensional Infrared Correlation Spectroscopy)分析技术,对野葛与粉葛进行无损快速鉴别研究。野葛和粉葛均为葛藤属植物,其外形极其相似,加工成粉末后更易混淆,但两种葛根的疗效并不完全相同,因此通过红外光谱法可对其进行无损快速鉴别研究。两种药材在一维红外光谱上略有差别,因此需要借助二阶导数光谱和二维红外光谱对其进行进一步的研究。结果表明,通过野葛与粉葛的红外光谱并结合二维相关光谱完全可以将其区别开来。该方法快速、准确,对中药的鉴别提供了一种新的方法和手段。     

岗梅与毛冬青的二维红外相关光谱鉴别研究

采用红外光谱法(FTIR)并结合二维相关光谱(Two-dimensionalInfrared CorrelationSpectrocopy)分析技术,对岗梅与毛冬青进行无损快速鉴别研究。岗梅与毛冬青皆为冬青属植物,其外形极其相似,加工成饮片后更易混淆,因此通过红外光谱对其进行无损快速鉴别研究。两种药材在一维谱上几乎没有显著差别,因此需要借助二阶导数谱和二维红外光谱对其进行进一步的研究。结果表明:通过岗梅与毛冬青的红外光谱并结合二维相关谱完全可以将其区别开来。该方法快速、准确,对中药的鉴别提供一种新的方法和手段。     

栽培与野生丹参的红外光谱三级鉴定研究

红外三级鉴定法可以区别和鉴定栽培和野生丹参,红外三级鉴定包括普通红外光谱、二阶导数谱和二维红外相关光谱,并且表观分辨率逐渐提高。栽培与野生丹参一维谱图峰形相似度很高,只是吸收峰波数有一定的差异。二阶导数谱则可看到在1500~1180cm-1波段栽培丹参在1410cm-1处有单峰,而野生丹参则出现分叉峰,分别在1420cm-1、1406cm-1处。在1180~850cm-1波段,栽培丹参在993cm-1、872cm-1处有比较强的吸收峰,而野生丹参在1032cm-1处有比较强的吸收峰。二维红外相关光谱中差异更明显,在1170~860cm-1波段,野生丹参在950cm-1处有很强的自动峰,而栽培丹参在此没有吸收峰;1500~1170cm-1波段野生丹参的峰强度要较栽培丹参大,依据自动峰的不同可以很容易的分辨出栽培与野生丹参。红外三级鉴定方法是一种快速有效的鉴定中药材的方法。     

胆结石有序结构的红外光谱研究

胆石病是徐州地区的多发病之一,利用傅里叶变换红外光谱（FTIR）针对胆结石的组成及生物矿化有序结构形成进行研究,初步探索该地区胆结石的形成过程。红外光谱分析表明：蛋白质为胆结石的形成提供沉淀基质,对于胆结石成核及有序结构的行程具有重要意义;在胆结石难溶物中胆固醇和羟基碳酸磷灰石相伴而生,推测羟基碳酸磷灰石可与胆固醇相互作用,促使其结晶析出,从而加速胆结石的形成。     

A spectroscopic study of a copper surface under boundary lubrication: I. Chemisorbed stearic acid multilayers

The thickness of chemisorbed stearic acid films on copper surfaces was deduced by Fourier transform infrared (FTIR) spectroscopy and Auger electron spectroscopy (AES). The chemisorption was detected by FTIR from the carboxyl (COO) asymmetric stretching band at 1585 cm⁻¹. Multilayer growth was observed by monitoring the intensity increase in the asymmetric CH₂ stretching mode at 2915 cm⁻¹. The growth of the chemisorbed layer was found to depend on the concentration of the stearic acid/hexadecane solution. The chemisorption kinetic profile had a step-function due to the change in the number of layers. High carbon concentration in Auger spectroscopic characterisation indicated that the surface was coated with a stearic acid film. AES depth profiling analysis supports this step-function model and agrees well with the FTIR results.     

Pressure jump relaxation setup with IR detection and millisecond time resolution

An instrument is described that allows the use of Fourier transform infrared (FTIR) spectroscopy as a detection system for kinetic processes after a pressure jump of up to 100 bars. The pressure is generated using a high performance liquid chromatography (HPLC) pump and water as a pressure transducing medium. A flexible membrane separates the liquid sample in the IR cell from the pressure transducing medium. Two electromagnetic switching valves in the setup enable pressure jumps with a decay time of 4 ms. The FTIR spectrometer is configured to measure time resolved spectra in the millisecond time regime using the rapid scan mode. All components are computer controlled. For a demonstration of the capability of the method first results on the kinetics of a phase transition between two lamellar phases of an aqueous phospholipid dispersion are presented. This combination of FTIR spectroscopy with the pressure jump relaxation technique can also be used for other systems which display cooperative transitions with concomitant volume changes.     

Detection and differentiation of biological species using microcalorimetric spectroscopy

We report on the application of infrared (IR) microcalorimetric spectroscopy ( micro -CalSpec) to the identification and detection of trace amounts of biological species. Our approach combines principles of photothermal IR spectroscopy with ultrasensitive microcantilever (MC) thermal detectors. We have obtained photothermal IR spectra for DNA and RNA bases and for Bacillus Cereus (an anthrax simulant) in the wavelength range of 2.5-14.5 micro m (4000-690 cm(-1)). The measurements are accomplished by absorbing biological materials directly on a MC thermal detector. The main advantage of the developed micro -CalSpec is its unprecedented sensitivity as compared to any of the previously explored IR techniques, including FTIR and photothermal FTIR methods. Our results demonstrate that <10(-9)g of a biological sample is sufficient to obtain its characteristic micro -CalSpec spectrum that contains information-rich chemical (vibrational) signatures. This opens up a new opportunity to create inexpensive high-throughput analytical systems for biochemical detection.