Spectroscopy micro

Techniques of microscopic XRF ( j,-XRF) developed in the last 20 years provide 2D images and elemental maps of each element present in the target material. Portable/in situ p-XRF, j,-XRF spectrometers synchrotron-based ( -SRXRF) and micro-x-ray absorption spectroscopy/micro-x-ray absorption near-edge structure spectroscopy (XAS/ J,-XANES) have improved the mineralogical characterization, as well as the elemental and chemical imaging of samples at the submicrometer scale [61]. 

Reshni, K.A., Morris, M.D., Johnson, B.N., Bums, M.A., On-line detection of electrophoretic separations on a microchip by Raman spectroscopy. Micro Total Analysis Systems 98, Proceedings pi AS 98 Workshop, Banff, Canada, 13-16 Oct. 1998, 109-112. 

Koglin, L. Combining HPTLC and Micro-Surface-Enhanced Raman Spectroscopy (Micro-SERS) , I Planar Chromator. 2,194-197, (1989)... 

In this chapter we first provide an overview of eommonly applied synchrotron radiation-based X-ray techniques for determining metal speciation in powdered samples, including X-ray absorption spectroscopy, micro X-ray fluorescence, and micro X-ray diffraction (XRD). The seeond part of this ehapter will provide an example of the application of these teehniques to an investigation of lead (Pb) speciation in a house dust sample, characterized by elevated total and bioaccessible Pb concentrations. 

Other useful microscopic analytical techniques include hot stage, fluorescence, and cathodolumines-cence microscopies micro-infrared spectroscopy micro-Raman spectroscopy ultraviolet-visible microspectrophotometry and X-ray diffraction however, the discussion of these techniques is beyond the scope of this article. Briefly stated, each of these techniques can be used to ascertain additional information about characteristic properties of a material. The microscopist must be aware of all of these techniques, and others, so as to be able to extract the necessary information from a sample when the need arises. 

Micro-Fourier Transform Infrared Spectroscopy Micro-Fourier transform infrared spectroscopy... 

Abstract Surface-enhanced Raman microprobe spectroscopy (micro-SERS) and near-infrared Fourier transform SERS spectroscopy (NIR-FT-SERS) are used to study, in situ, the adsorption process of alkylpyridinium bromide (C PyBr) and alkyltrimethylammonium bromide (C TAB) adsorbed on charged silver nanoparticle surfaces. Vibrational assignment was achieved by comparison of observed band position and intensity in the Raman spectra with wave numbers and intensities from ab initio LCAO-MO-SCF Hartree-Fock calculations at the 6-3IG level. 

Koglin, E. (1989). Combining HPTLC and micro-surface-enhanced Raman spectroscopy (micro-SERS). J. Planar Chromatgr.—Mod. TLC 2 194—197. 

Feature Micro-IR spectroscopy Micro-Raman spectroscopy... 

Structural transformations in nanophase Ti02 were followed by Raman spectroscopy. " Micro-Raman studies have been reported for pure Ti02 and Nb-Ti-O nanoparticles.The Raman spectra of the (Ta205)i x(Ti02)x system over a range of temperatures and pressures showed characteristic vTiO and vTaO bands. 

Fourier transform infrared spectroscopy Micro-flow imaging Poly(dimethylsiloxane) Polymethylsilsesquioxane Quartz crystal microbalance Random sequential adsorption Surface plasmon resonance Total internal reflection fluorescence X-ray photoelectron spectroscopy... 

Alia- testing, the following test methods were performed on the selected tested specimens Visual examination of the specimens was performed to identify the modes of failure. Oxidation induction time (OIT) was performed in general accordance with ISO 11357-6-2002 (E) [10] at 200 °C. Specimens wo-e taken liom the inner and outer surfaces as well as liom the bulk pipe wall and Micro-attenuated total reflection Fourier Transform Infrared Spectroscopy (micro-ATR) was performed. The inner surface and the fracture surface were examined. Scaiming Eleetron Microscopy (SEM) coupled with Energy Dispersive X-ray analysis (EDX) was performed on the iimer surface and the fiacture surface. 

Turrell G and Dhamelincourt P 1996 Micro-Raman spectroscopy Modern Techniques in Raman Spectroscopy ed J J Laserna (New York Wiley) pp 109-42... 

Scale of Operation Atomic absorption spectroscopy is ideally suited for the analysis of trace and ultratrace analytes, particularly when using electrothermal atomization. By diluting samples, atomic absorption also can be applied to minor and major analytes. Most analyses use macro or meso samples. The small volume requirement for electrothermal atomization or flame microsampling, however, allows the use of micro, or even ultramicro samples. 

Information exists about the use of measuring cells made entirely of diamond or graphite with or without embedded diamond windows. Diamond cells were used, for instance, by Toth and Gilpatrick [333] in the investigation of the Nb(IV) spectrum in a LiF - BeF2 molten system at 550°C. Windowless graphite cells for the IR spectroscopy of melts were developed by Veneraky, Khlebnikov and Deshko [334]. Diamond, and in some cases windowless sapphire or graphite micro-cells, were also applied for Raman spectroscopy measurements of molten fluorides. 

In order to supplement micro-mechanical investigations and advance knowledge of the fracture process, micro-mechanical measurements in the deformation zone are required to determine local stresses and strains. In TPs, craze zones can develop that are important microscopic features around a crack tip governing strength behavior. For certain plastics fracture is preceded by the formation of a craze zone that is a wedge shaped region spanned by oriented micro-fibrils. Methods of craze zone measurements include optical emission spectroscopy, diffraction... 

Igniters, Incendiaries, Boosters, and Delay Compositions on a Micro Scale by Use of Infrared Spectroscopy , FrankfordArs Rept T-71-6-1 (1971) 8) G.A. St John M. 

Network properties and microscopic structures of various epoxy resins cross-linked by phenolic novolacs were investigated by Suzuki et al.97 Positron annihilation spectroscopy (PAS) was utilized to characterize intermolecular spacing of networks and the results were compared to bulk polymer properties. The lifetimes (t3) and intensities (/3) of the active species (positronium ions) correspond to volume and number of holes which constitute the free volume in the network. Networks cured with flexible epoxies had more holes throughout the temperature range, and the space increased with temperature increases. Glass transition temperatures and thermal expansion coefficients (a) were calculated from plots of t3 versus temperature. The Tgs and thermal expansion coefficients obtained from PAS were lower titan those obtained from thermomechanical analysis. These differences were attributed to micro-Brownian motions determined by PAS versus macroscopic polymer properties determined by thermomechanical analysis. 

Keywords Micro-optics, MOEMS, multi-object spectroscopy, adaptive optics, astronomi-... 

In the design of MOEMS components, various parameters have to be tuned. These parameters differ according to the functionality of the component. We will consider two different family of devices, programmable slits for Multi-Object Spectroscopy, including Micro-Mirror Arrays (MMA) and Micro-Shutters Arrays (MSA), and Micro-Deformable Mirrors (MDM) for Adaptive Optics systems. 

Figure 1. Principle of Multi-Object Spectroscopy using a Micro-Mirror Array. MMA array in the park position and in action...

Micro-Opto-Electro-Mechanical Systems (MOEMS) will be widely integrated in new astronomical instruments for future Extremely Large Telescopes, as well as for existing lOm-class telescopes. The two major applications are programmable slit masks for Multi-Object Spectroscopy (see Ch. 12) and deformable mirrors for Adaptive Optics systems. Eirst prototypes have shown their capabilities. However, big efforts have stiU to be done in order to reach the requirements and to realize reliable devices. 

The brief history, operation principle, and applications of the above-mentioned techniques are described in this chapter. There are several other measuring techniques, such as the fluorometry technique. Scanning Acoustic Microscopy, Laser Doppler Vibrometer, and Time-of-flight Secondary Ion Mass Spectroscopy, which are successfully applied in micro/nanotribology, are introduced in this chapter, too. 

Concrete applications of micro reactors for chemical analysis, albeit so far not a core application, have been described [5]. Among other uses in chemical analysis, micro devices for gas chromatography, infrared spectroscopy, and photoacoustic detection are mentioned. 

However, as Raman scattering is a two-photon process, the probability of the Raman scattering process is lower than that of fluorescence and IR absorption processes. The cross section of Raman scattering is 10 cm, which is much smaller than that of fluorescence ( 10 cm ) and IR absorption ( 10 °cm ). When we detect Raman scattering at the nanoscale, the number of photons obtained is less than with the usual micro-Raman spectroscopy due to reduction in the detection area or the number of molecules. To overcome this problem, we need to devise a method for amplification of Raman scattering. 

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