A Fourier-transform infrared spectral study of propene reactions on acidic zeolites

The IRμs™ is the first fully integrated system for Fourier transform infrared (FT-IR) microscopy. FT-IR microscopy combines light microscopy for morphological examination with infrared spectroscopy for chemical identification of microscopic samples or domains. Because the IRμs system is a new tool for molecular microanalysis, its optical, mechanical and system design are described to illustrate the state of development of molecular microanalysis. Applications of infrared microspectroscopy are reviewed by Messerschmidt and Harthcock.Infrared spectral analysis of microscopic samples is not a new idea, it dates back to 1949, with the first commercial instrument being offered by Perkin-Elmer Co. Inc. in 1953. These early efforts showed promise but failed the test of practically. It was not until the advances in computer science were applied did infrared microspectroscopy emerge as a useful technique. Microscopes designed as accessories for Fourier transform infrared spectrometers have been commercially available since 1983. These accessory microscopes provide the best means for analytical spectroscopists to analyze microscopic samples, while not interfering with the FT-IR spectrometer’s normal functions.

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Fourier transform infrared spectral evidences for protein conformational changes in immature cataractous human lens capsules accelerated by myopia and/or systemic hypertension

Spectrochimica Acta Part A Molecular and Biomolecular Spectroscopy ◽

10.1016/s1386-1425(97)00077-2 ◽

1997 ◽

Vol 53 (9) ◽

pp. 1507-1513 ◽

Cited By ~ 7

Author(s):

Shan-Yang Lin ◽

Shui-Mei Lee ◽

Mei-Jane Li ◽

Run-Chu Liang

Keyword(s):

Fourier Transform ◽

Conformational Changes ◽

Fourier Transform Infrared ◽

Systemic Hypertension ◽

Human Lens ◽

Protein Conformational Changes ◽

Infrared Spectral

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Application of Gas Chromatography/Matrix Isolation/Fourier Transform Infrared Spectroscopy to the Identification of Pyrrolizidine Alkaloids from Comfrey Root (Symphytum officinale L.)

Journal of AOAC International ◽

10.1093/jaoac/77.5.1167 ◽

1994 ◽

Vol 77 (5) ◽

pp. 1167-1174 ◽

Cited By ~ 6

Author(s):

Magdi M Mossoba ◽

Hubert S Lin ◽

Denis Andrzejewski ◽

James A Sphon ◽

Joseph M Betz ◽

...

Keyword(s):

Gas Chromatography ◽

Fourier Transform ◽

Pyrrolizidine Alkaloids ◽

Matrix Isolation ◽

Fourier Transform Infrared ◽

Root Extract ◽

Spectral Bands ◽

Infrared Spectral ◽

Fingerprint Region ◽

Positive Ion

Abstract This paper demonstrates that pyrrolizidine alkaloids (PAs) extracted from comfrey root grown in Washington State (USA) can be identified by gas chromatography/matrix isolation/Fourier transform infrared (GC/MI/FTIR) spectroscopy. Infrared spectral bands observed in the fingerprint region were unique even for closely related structures. The identities of the 4 major components, intermedine, lycopsamine, 7-acetylintermedine, and 7-acetylly-copsamine, were confirmed by comparison with standards. Confirmation was also obtained by using the established techniques of electron ionization and positive ion chemical ionization gas chro-matography/mass spectrometry. The infrared spectra observed for the components of the root extract were consistent with known structures of specific PAs. The identities of the minor components, sym-phytine and its isomers symlandine and/or sym-viridine, in the same extract were not confirmed.

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Fourier Transform Infrared Spectral Analysis of Polyisoprene of a Different Microstructure

International Journal of Polymer Science ◽

10.1155/2013/937284 ◽

2013 ◽

Vol 2013 ◽

pp. 1-5 ◽

Cited By ~ 16

Author(s):

Dongmei Chen ◽

Huafeng Shao ◽

Wei Yao ◽

Baochen Huang

Keyword(s):

Nuclear Magnetic Resonance ◽

Spectral Analysis ◽

Fourier Transform ◽

Magnetic Resonance ◽

Detailed Analysis ◽

Fourier Transform Infrared ◽

Ftir Spectra ◽

H Nmr ◽

Infrared Spectral

Some polyisoprene samples of different microstructure contents were studied by Fourier transform infrared (FTIR) and1H Nuclear magnetic resonance (1H NMR). On the basis of detailed analysis of FTIR spectra of polyisoprene, the shift of absorption peaks caused by microstructure content’s variation was discussed. The contents of the polyisoprene samples’ microstructure which was determined by the1H NMR was used as the standard. Through the choice, calculation, and comparison with the corresponding absorption peaks of FTIR, a method based on the results of the analysis has been developed for the determination of the microstructure contents of polyisoprene by FTIR.

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Analysis of IHchothecene Mycotoxins in Contaminated Grains by Gas Chromatography/Matrix Isolation/Fourier Transform Infrared Spectroscopy and Gas Chromatography/Mass Spectrometry

Journal of AOAC International ◽

10.1093/jaoac/79.5.1116 ◽

1996 ◽

Vol 79 (5) ◽

pp. 1116-1123 ◽

Cited By ~ 10

Author(s):

Magdi M Mossoba ◽

Sarah Adams ◽

John A G Roach ◽

Mary W Trucksess

Keyword(s):

Mass Spectrometry ◽

Gas Chromatography ◽

Fourier Transform ◽

Sweet Corn ◽

Matrix Isolation ◽

Fourier Transform Infrared ◽

Epoxide Ring ◽

Absorption Bands ◽

Spectral Bands ◽

Infrared Spectral

Abstract Gas chromatography/matrix isolation/Fourier transform infrared (GC/MI/FTIR) spectroscopy and GC/mass spectrometry (MS) were used to confirm the identities of trimethylsilyl (TMS) derivatives of trichothecene mycotoxins in naturally contaminated grains. Infrared spectral bands observed in the fingerprint region were unique for 10 trichothecene standards. Characteristic absorption bands were observed for the ester (near 1750 cm-1) and ketone (near 1700 cm-1) carbonyl stretching vibrations, the acetate CH3 symmetric bend (1370 cm-1), the epoxide ring (1262 cm-1), the trimethylsilyl CH3 in-plane deformation (1253 cm-1), the ester (O)C-O asymmetric stretching vibration (near 1244 cm-1), and several other bands including intense features due to the TMS function. Infrared bands observed under cryogenic matrix isolation conditions were compared with those found at room temperature in a potassium bromide matrix for 5 of these standards. Identities of deoxynivalenol (DON) from barley and mixed feed, nivalenol from wheat and barley, and DON and fusarenon-x from sweet corn were confirmed by comparison of their infrared spectral bands with those of standards. The identity of DON in the same test samples of sweet corn was confirmed further by GC/MS. GC/MS was also used to quantitate the levels of DON (67-455 ppm) in sweet corn test samples.

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