Fourier-transform IR spectrometry

Methods and iastmments that are used to monitor phosgene content ia air are well developed and have been reviewed (46—48). One detection iastmment is a porous tape that measures the concentration of phosgene ia air ia quantities as small as 6 ppb (49). Fourier transform ir spectrometry techniques have been developed to permit line and area monitoring ia the area around phosgene plants (50). 

Size-Exclusion Chromatography-Fourier Transform IR Spectrometry Using a Solvent-Evaporative Interface... 

The use of additive isolation procedures and Fourier transform IR spectrometry for quantifying external and internal stearic acid lubricant in PS resins is discussed and advantages over previously-used techniques are considered. 13 refs. 

Infrared (IR) spectra of organic compounds are characteristic of various functional groups in the molecules. IR spectral information is somewhat complementary to mass spectral information. Therefore, the combination of GC with IR spectroscopy is, after GC/mass spectrometry, the second most important structural identification tool. Since conventional IR spectroscopy is less sensitive than most GC detectors, the necessary sensitivity enhancement is achieved through the use of Fourier transform techniques. With the advent of refined optical systems and fast computational techniques, the combination of GC with Fourier-transform IR spectrometry is becoming widely used, although its sensitivity is currently less than that of mass spectrometry. Special optical cells were designed for the purposes of this combination. 

It is demonstrated that the above technique can detect and identify (by chemical formulae) dyes in solid PMMA commercial plastics at concentrations at least on order of magnitude lower (0.1% vs l-2wt%) than those obtained by the best currently-available alternative method (ATR Fourier transform IR spectrometry). Both untreated and redissolved PMMA can be characterised, in the presence and absence of up to three dyes in a single sample. 44 refs. USA... 

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... 

In Chapter 12, the use of mass spectrometry and Fourier transform infrared spectrometry (FTIR) for GC detection was discussed. Details of these techniques were individually given in Chapters 10 and 12. Much of the discussion presented in Chapter 16 is applicable here. Both liquid chromatography-mass spectrometry (LC-MS) and liquid chromatography-infrared spectrometry (LC-IR) have been adapted to HPLC detection in recent years. 

The synthesis of the module is provided in Scheme 10.5 (Kushner et al. 2007). Double alkylation of ethyl acetoacetate followed by guanidine condensation afforded alkenyl-pyrimidone intermediate 24 (Kushner et al. 2007). Isocyanate 25 was coupled to pyrimidone 24 to yield 26. Upon dimerization in DCM, RCM effectively cyclized the two UPy units (Mohr et al. 1997 Week et al. 1999). A one-pot reduction and deprotection through hydrogenation using Pearlman s catalyst gave diol module 27. Finally, capping 27 with 2-isocyanatoethyl methacrylate at both ends provided the UPy sacrificial cross-linker 28, which was thoroughly characterized by H- and C-NMR, Fourier transform IR (FTIR), and mass spectrometry. 

MS, Mass spectrometry El, electron impact Cl, chemical ionization MID, multiple ion detection PICI, positive-ion chemical ionization NICI, negative-ion chemical ionization SIM, selected ion nmonitoring TSP, thermospray PPINICI, pulsed positive ion-negative ion chemical ionization ECD, electron-capture detector NPD, nitrogen/phosphorous detector NSTD, nitrogen-selective thermionic detector FT-IR, Fourier transform infrared spectrometry. 

Infrared-spectrometry (IR) was used for the investigation of substituent acetyl groups in the molecules of the polysaccharides. A Fourier transform IR Perkin-Elmer spectrometer, Model 1720-X, was used. The... 

Dihydrobis (pyrazolyl )borate Dihydrobis (3,5-dim ethylpy razolyl )borate Cholecystokinin Cyclohexanedionedioxime Central nervous system 2-(Diphenylphosphanyl)benzoic acid 2,3-Diaminopropionic acid Electrospray ionization mass spectrometry Fourier transform IR Gastrin-releasing peptide... 

Fourier transform/infrared spectrometry (FT/IR) detects and identifies CWAs by measuring the infrared spectrum of the air sample noninvasively and instantly (Mukhopadhyay 2004). Considering the interference of water and carbon dioxide, characteristic absorbance peaks in the low-wave number region are used as the specific marker. Portable FT-IR equipment is commercially available. IGA-1700 (Otsuka Electronics, Japan) and DX-4000 (Temet, Finland) showed... 

The polysiloxanes were characterized by Fourier transform-IR (FTIR) spectroscopy, H and Si NMR spectrometry, and by GPC. AC conductivities of the polymer electrolytes were measured under dry helium by using an automatic capacitance bridge (General Radio Corporation). Glass transition (Tg) and melt (TJ temperatures were recorded on a differential scanning calorimeter (Perkin Elmer DSC-4). More detailed experimental procedures are published elsewhere (9, 12). 

Romanach and de Haseth [3] have used, in CCC, a how cell for LC-FTIR (liquid chromatography-Fourier transform infrared) spectrometry. The main difflculty is the absorbance of the liquid mobile phase. This problem is exacerbated in EC by low solute-to-solvent ratios in the eluates. On the contrary, CCC leads to a high solute-to-solvent ratio so that it can be used with a very simple interface with a CCC column, without any complex solvent removal procedures. High sample loadings are possible by using the variable path length of the IR detector (from 0.025 to 1.0 mm). 

DAD, diode array detector p.b., phosphate buffer FT-IR, Fourier transform infrared spectrometry. 

In addition, a number of advanced analytical techniques, such as low temperature luminescence spectroscopy, tandem mass spectrometry (MS/MS), Fourier-Transform IR-spectroscopy and nuclear magnetic resonance spectrometry have been successfully applied to PAH analysis. For instance, low temperature luminescence spectrometry, sometimes in combination with laser excitation, was used for the analysis of PAH in various matrices without prior separation, which is attractive especially for screening or finger-printing purposes (10, 73). However, a wider application for routine analysis is at present inhibited by the limited availability of the required equipment. The same remark applies to tandem mass spectrometry, FT-IR spectroscopy and NMR. All three techniques, however, are increasingly used for the detection and identification of novel PAH species and derivatives and efforts are continuing towards coupling IR and NMR as detectors to GC and HPLC (74) respectively. 

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