Fourier Transform Raman spectroscop

Kirchner, M.T., Edwards, H. G. M., Lucy, D., and Pollard, A. M. (1997). Ancient and modern specimens of human teeth a Fourier transform Raman spectroscopic study. Journal of Raman Spectroscopy 28 171-178. 

J.-H. Jiang, Y. Ozaki, M. Kleimann and H.W. Siesler, Resolution of two-way data from on-line Fourier-transform Raman spectroscopic monitoring of the anionic dispersion polymerization of styrene and 1,3-butadiene by parallel vector analysis (PVA) and window factor analysis (WFA), Chemom. Intell. Lab. Syst., 70, 83-92... 

Once deposition is complete and the initial reaction product is trapped in an inert gas matrix, characterization is carried out spectroscopically. Several spectroscopic techniques have been used the most common is infrared spectroscopy, either dispersive or Fourier transform. Raman spectroscopic studies have been carried out as well, but low signal levels have made this approach difficult. When the trapped intermediate is a free radical, electron spin resonance techniques are valuable as well. Finally, a number of researchers are employing electronic spectroscopy, when the species of interest has an absorption in the visible or ultraviolet tegion. 

Fourier Transform Raman Spectroscopic Study of the Interaction of... 

Score values of the first principal component following analysis of the 1550 to 600 cm spectral region plotted against the mole fraction water. Source Reproduced from Taylor, L.S., Langkilde, F.W., and Zografi, G. Fourier transform Raman spectroscopic study of the interaction of water vapor with amorphous polymers, /. Pharm. Set., 90,888-901,2001. With permission of the copyright owner.)... 

AH Kuptsov. Fourier Transform Raman Spectroscopic Investigation of Paper. Vibrational Spectrosc. 7 185-190, 1994. 

No.8, 1993, p. 1649-52 FOURIER TRANSFORM-RAMAN SPECTROSCOPIC STUDY OF ELECTRICALLY CONDUCTING POLYPYRROLE FILMS... 

R. M. Osuna, R. P. Ortiz, V. Hernandez, J. T. L. Navarrete, M. Miyasaka, S. Rajca, A. Rajca and R. Glaser, Helically annelated and cross-conjugated beta-ohgothiophenes a Fourier transform Raman spectroscopic and quantum chemical density functional theory study, J. Phys. Chem. C, 111, 4854-4860 (2007). 

Taylor LS, Langkilde FW, Zografi G (2001) Fourier transform Raman spectroscopic study of the interaction of water vapor with amorphous polymers. J Pharm Sd 90 888-901... 

YH Yang, T Wang. Fourier-transform Raman spectroscopic characterization of humic substances. Vib Spectrosc 14 105-112, 1997. 

WF Maddams. A review of Fourier-transform Raman spectroscopic studies on polymers. Spectro-chim Acta 50A 1967-1986, 1994. 

F Rull, HGM Edwards, A Rivas, L Drummond. Fourier transform Raman spectroscopic characterization of pigments in the mediaeval frescoes at Convento de la Peregrina, Sahagun, Leon, Spain. Part 1—Preliminary study. J. Raman Spectrosc 30 301-305, 1999. 

HGM Edwards, CJ Brooke, JKF Tait. Fourier transform Raman spectroscopic study of pigments from English mediaeval wall paintings. J Raman Spectrosc 28 95-98, 1997. 

HGM Edwards, DW Farwell, F Rull, S Jorge. Spanish mediaeval frescoes at Basconcillos del Tozo A Fourier transform Raman spectroscopic study. J Raman Spectrosc 30 307-311, 1999. 

HGM Edwards, L Drummond, J Russ. Fourier-transform Raman spectroscopic study of prehistoric rock paintings from the Big Bend Region, Texas. J Raman Spectrosc 30 421-428, 1999. 

Perch-Nielsen (1973) Perch-Nielsen, K. Fossil coccohths as indicators of late Cretaceous chalk used in Mediaeval Art Oldsaksamlingens Arbok (1973) 161-169 Perez et al. (1999) Perez, F.R. Edwards, H.G.M. Rivas, A. Drummond, L. Fourier transform Raman spectroscopic characterization of pigments in the mediaeval frescoes at Convento de la Peregrina, Sahagun, Leon, Spain Part 1 Preliminary Study Journal of Raman Spectroscopy 30 (1999) 301-305 Perez-Llano (1944) Perez-Llano, G.A. Lichens, their biological and economic significance The Botanical Review 10 1 (1944) 1-65... 

Fourier-transform Raman and Fourier-transform infrared spectroscopic methods were adapted for the analysis of spironolactone and differentiation of its polymorphic forms [31,32],... 

Infrared spectroscopy is an important technique for studying acidity. Acidic OH groups can be studied directly. Probe molecules such as pyridine may be used to study both Bronsted and Lewis acidity since two forms of adsorbed probes are easily distinguished by their infrared spectra. Quantitative infrared spectroscopy may be performed by measuring the spectrum of acidic OH or probes adsorbed on thin, self-supporting wafers of the acidic solid. Other spectroscopic methods which may provide information in specific cases include Fourier Transform Raman spectroscopy, electron spin resonance spectroscopy, ultraviolet spectroscopy, and nuclear magnetic resonance spectroscopy. 

More research is needed with both spectroscopic tools, especially with the recent advances in the field of Fourier transform Raman spectroscopy and the tremendously improved sensitivity and stability of the IR interferometers. In addition, the availability of new algorithms such as the ratio method (32), factor analysis (20, 33), and recently developed nonlinear techniques (34), coupled with an easy access to fast computers, will advance spectral analysis tremendously and make it more precise and reliable. 

Rao and co-workers [82] used an inverted emulsion process for the synthesis of the emeraldine salt of PAM using a novel oxidising agent, benzoyl peroxide. The polymerisation was carried out in a non-polar solvent in the presence of four different protonic acids as dopants and an emulsifier (sodium lauryl sulfate). The polymer salts were characterised spectroscopically by ultraviolet-visible, Fourier-transform infrared, Fourier-transform Raman and electron paramagnetic resonance spectroscopy. Thermogravimetric analysis, was used to determine the stability of the salts and the activation energy for the degradation. The conductivity of the salts was found to be in the order of 10 S/cm. 

Raman spectroscopy is a vibrational spectroscopic technique which can be a useful probe of protein structure, since both intensity and frequency of vibrational motions of the amino acid side chains or polypeptide backbone are sensitive to chemical changes and the microenvironment around the functional groups. Thus, it can monitor changes related to tertiary structure as well as secondary structure of proteins. An important advantage of this technique is its versatility in application to samples which may be in solution or solid, clear or turbid, in aqueous or organic solvent. Since the concentration of proteins typically found in food systems is high, the classical dispersive method based on visible laser Raman spectroscopy, as well as the newer technique known as Fourier-transform Raman spectroscopy which utilizes near-infrared excitation, are more suitable to study food proteins (Li-Chan et aL, 1994). In contrast the technique based on ultraviolet excitation, known as resonance Raman spectroscopy, is more commonly used to study dilute protein solutions. 

Syndiotactic polypropylene also exists as two crystalline modifications, the more stable one possessing a helical conformation and the other a planar zig-zag, A detailed analysis of the Raman spectrum confirms these structures and there is an excellent correlation between observed and predicted vibrational modes of the helical structure. Painter et al. have made a Fourier transform infrared spectroscopic study of isotactic polypropylene in the crystalline and amorphous state. The spectrum of the amorphous regions is broadly similar to that of the melt, but there is evidence for short sequences of helical segments in the amorphous phase, while the crystalline phase has longer sequences. This puts a different interpretation on the distinction between amorphous and crystalline regions than previously considered. 

Raman and infrared spectra have also been compared for a series of 1,4-benzodiazepines, including diazepam (Vallium) and of closely related compounds [16,17]. The complementary nature of these two vibrational spectroscopic techniques was highlighted and the data provided spectral features that allowed identification of the drugs. The value of Fourier transform Raman spectroscopy using a near-infrared excitation source was also demonstrated for these heterocyclic molecules which have a tendency to fluoresce with visible radiation from conventional dispersive Raman spectrometers. 

PJ Treado, MD Morris. Infrared and Raman spectroscopic imaging. Appl Spectrosc 29 1-38, 1994. P Schmidt, PJ Hendra. The application of Fourier-transform Raman spectroscopy to the determination of conformation in poly( -caprolactam) chains. Spectrochim Acta 50A 1999-2004, 1994. SPS Porto. Angular dependence and depolarization ratio of the Raman effect. J Opt Soc Am 56 1585-1589, 1966. 

The above describes the commonly utilized instrumentation required for dispersive Raman spectroscopic microscopy. In the past, Fourier transform Raman spectroscopy provided an alternative for coloured and fluorescent samples but the use of near-IR lasers at 1.064 pm together with In Ga As detectors reduced the sensitivity. Recent developments in laser rejection Alters and CCD technologies have rendered dispersive techniques the preferred option. 

This method has also been applied to medical problems related to disease diagnosis (e.g. arthero-sclerotic plaque) or optimization of medical treatment (e.g. bone implants). Flowever, medical applications of Raman spectroscopy do not necessarily require the combination with microscopy. Numerous studies have indicated that based on the analysis of Raman spectra by statistical methods it is possible to differentiate between normal and pathological tissues. Despite the substantial technical improvements, the intrinsically low sensitivity of Raman spectroscopy constitutes a limit for general applicability. Fluorescent samples may impose an additional constraint, which, however, can be overcome by near-infrared (1064 nm) Fourier-transform Raman spectroscopy and microscopy. In summary, it appears that for special medical applications Raman spectroscopic techniques may become a powerful diagnostic tool in clinical situations. 

Plate 3 Ivory cat, which was identified spectroscopically as a modern limitation composed of poly(methyl methacrylate) and polystyrene resins with added calcite to give the texture and density of ivory. Reproduced with permission from Edwards HGM and Farwell DW, Ivory and simulated ivory artefacts Fourier-transform Raman diagnostic study, Spectrochimica Acta, Part A, 51 2073-2081 1995, Elsevier Science B. V. See Art Works Studied using IR and Raman Spectroscopy. 

At least two Raman spectroscopic methods are applicable in membrane surface characterization Fourier transform Raman spectroscopy (FT-Raman), and micro-Raman spectroscopy (Boccaccio et al., 2002 Gmger et al., 2001 Khulbe and Matsuura, 2000). In FT-Raman the sample molecules are excited with a near-infi ared (NIR) laser and appropriately configured Michelson interferometers, and Fomier transform processes are used in the collecting of scattered light and the analysis of the collected light. Almost the only requirement is that the sample to be analyzed with FT-Raman must not be black (Hendra, 2005). FT-Raman is a valuable tool in determining the overall chemical stmcture of a membrane, but it cannot characterize the asymmetric stmcture of a porous membrane matrix (Boccaccio et al., 2002). 

With recent developments in analytical instrumentation these criteria are being increasingly fulfilled by physicochemical spectroscopic approaches, often referred to as whole-organism fingerprinting methods.910 Such methods involve the concurrent measurement of large numbers of spectral characters that together reflect the overall cell composition. Examples of the most popular methods used in the 20th century include pyrolysis mass spectrometry (PyMS),11,12 Fourier transform-infrared spectrometry (FT-IR), and UV resonance Raman spectroscopy.16,17 The PyMS technique... 

An important tool for the fast characterization of intermediates and products in solution-phase synthesis are vibrational spectroscopic techniques such as Fourier transform infrared (FTIR) or Raman spectroscopy. These concepts have also been successfully applied to solid-phase organic chemistry. A single bead often suffices to acquire vibrational spectra that allow for qualitative and quantitative analysis of reaction products,3 reaction kinetics,4 or for decoding combinatorial libraries.5... 

---