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FT-IR-spectroscopy

Therefore, it can be convincingly deduced that combination of SWNT-SDS perpetuates more restrictions on electronic like band of PANI as compared to SWNT-NaDBS. [Pg.72]


Determination of Carbon Monoxide in Automobile Exhaust by FT-IR Spectroscopy, /. Chem. Educ. 1988, 65, 820-823. [Pg.448]

MONITORIZATION OF Ca(OH), CONTENT IN ANHYDRITE, SUBPRODUCT OF HF PRODUCTION PROCESS, BY FT-IR SPECTROSCOPY USING PLS CALIBRATION METHOD... [Pg.200]

Regarding the characterization of corn cob xylan by Fourier-transform infrared (FT-IR) spectroscopy, two main absorption bands at 3405 cm-i and 1160 cm-i are revealed. They can... [Pg.67]

The growth and decay of all other species (including O3) were monitored by Fourier transform infrared (FT-IR) spectroscopy at a total pathlength of 460 meters and a spectral resolution of 1 cm". At this pathlength, the intense absorptions of H2O and CO limit the usable IR spectral windows to the approximate regions 750-1300, 2000-2300, and 2400-3000 cm". Each spectrum (700-3000 cm" ) was adequately covered by the response of the Cu Ge detector. Approximately 40 seconds were required to collect the 32 interferograms co-added for each spectrum. [Pg.118]

Coimbra, M.A. et al., Quantification of polymeric mannose in wine extracts by FT-IR spectroscopy and OSC-PLSl regression, Carbohydrate Poly., 61, 434, 2005. [Pg.506]

Yeom and Frei [96] showed that irradiation at 266 nm of TS-1 loaded with CO and CH3OH gas at 173 K gave methyl formate as the main product. The photoreaction was monitored in situ by FT-IR spectroscopy and was attributed to reduction of CO at LMCT-excited framework Ti centers (see Sect. 3.2) under concurrent oxidation of methanol. Infrared product analysis based on experiments with isotopically labeled molecules revealed that carbon monoxide is incorporated into the ester as a carbonyl moiety. The authors proposed that CO is photoreduced by transient Ti + to HCO radical in the primary redox step. This finding opens up the possibility for synthetic chemistry of carbon monoxide in transition metal materials by photoactivation of framework metal centers. [Pg.55]

It is generally assumed the fluorescence and Fourier transform mid-infrared (FT-IR) spectroscopies do not suffer from the above-mentioned inconveniences and may be applied to turbid samples. Front-face (fluorescence) and attenuated total reflection (FT-IR) techniques may provide information on the structure of adsorbed proteins. [Pg.266]

Montanari el al., for example, studied a Co—H-MFI sample through FT-IR spectroscopy of in situ adsorption and coadsorption of probe molecules [o-toluonitrile (oTN), CO and NO] and CH4-SCR process tests under IR operando conditions. The oTN adsorption and the oTN and NO coadsorption showed that both Co2+ and Co3+ species are present on the catalyst surface. Co3+ species are located inside the zeolitic channels while Co2+ ions are distributed both at the external and at the internal surfaces. The operando study showed the activity of Co3+ sites in the reaction. The existence of three parallel reactions, CH4-SCR, CH4 total oxidation and NO to NOz oxidation, was also confirmed. Isocyanate species and nitrate-like species appear to be intermediates of CH4-SCR and NO oxidation, respectively. A mechanism for CH4-SCR has been proposed. On the contrary, Co2+ substitutional sites, very evident and predominant in the catalyst, which are very hardly reducible, seemed not to play a key role in the SCR process [173],... [Pg.128]

Lesage, T., Verrier, C., Bazin, P. el al. (2003) Studying the NOx-trap mechanism over a Pt-Rh/Ba/Al203 catalyst by operando FT-IR spectroscopy, Phys. Chem. Chem. Phys., 5, 4435. [Pg.140]

In order to document the radical disproportionation reaction, we have used FT-IR spectroscopy to characterize the irradiation products. Upon irradiation of 1 in pentane, the formation of the characteristic peak near 2100 cm-1 due to Si-H stretching vibrations was readily apparent. The IR spectrum obtained in perdeuterated pentane was identical, suggesting that radical processes other than abstraction from the solvent are involved. Furthermore the ESR spectrum obtained in this solvent is identical to that already described. This raises the question whether the initially formed silyl radicals really abstract hydrogen from carbon with the formation of carbon-based radicals as suggested (13), particularly in light of the endothermicity of such a process. [Pg.74]

Sukhov, D. A., O. Y. Derkacheva, S. A. Kazansky, and D. M. Kheyfetz (1995), The new prospects of FT-IR spectroscopy for non destructive testing of artistic and cultural objects, Proc. 4th Int. Conf. Non Destructive Testing of Works of Art, Berlin, Oct. 1994, Deutsche Geselltschaft fur Zertorungsfrei Prufung, Berlin, pp. 795-798. [Pg.617]

Normally, time-resolved FT-IR spectroscopy (TRS FT-IR) possesses the same data characteristics. In a typical TRS FT-IR experiment, interferograms are assembled for a specific delay time after the photolysis pulse, and the data produced are normally finer-grained in frequency than in time. This type of experiment is complementary to experiments with fine-grained time information. It is particularly useful where a wide spectral range is necessary and works reasonably well for highly reproducible events which occur on relatively long timescales (fractions of seconds) (83). It is also an appealing system for use on shorter timescales, and it has... [Pg.298]

Philippova and Starodubtzev have also extensively studied the complex-ation behavior of polyacids and PEG, especially, the system of crosslinked of poly(methacrylic acid) and linear poly(ethylene glycol) (Philippova and Starodubtzev, 1995 Philippova et al., 1994). They observed that decreasing the molecular weight of PEG from 6000 to 1500 resulted in its slower diffusion into the swollen network of PMAA, and a drastic decrease in both the stability and equilibrium composition of the intermacromolecular complex. Analysis of dried polymer networks of PMAA with absorbed PEG chains by FT-IR spectroscopy revealed the presence of two types of hydrogen bonded structures (1) dimers of methacrylic acid at absorption frequency of 1700 cm-1 and (2) interpolymer complexes of PMAA and PEG at 1733 cm-1. In addition, they also suggested as a result of their studies, that the hydrogen bonded dimer of PMAA forms preferentially to the intermacromolecular complex between the PMAA network and PEG chains. [Pg.94]

Complex formation between Co and chelating agents was investigated by FT-IR spectroscopy after the second impregnation followed by drying. The dried sample was diluted with KBr powder and then formed into a self-supporting wafer. FT-IR measurements were carried out in a transmittance mode on an FTS6000 FT-IR spectrometer (Varian) with spectral resolution and accumulation time of 4 cm 1 and 1,024, respectively. [Pg.99]

Vasenkov, S. and Frei, H. (2000). Time-resolved study of acetyl radical in zeolite NaY by step-scan FT-IR spectroscopy. J. Phys. Chem. A 104, 4327 4332... [Pg.263]

NMR) [24], and Fourier transform-infrared (FT-IR) spectroscopy [25] are commonly applied methods. Analysis using mass spectrometric (MS) techniques has been achieved with gas chromatography-mass spectrometry (GC-MS), with chemical ionisation (Cl) often more informative than conventional electron impact (El) ionisation [26]. For the qualitative and quantitative characterisation of silicone polyether copolymers in particular, SEC, NMR, and FT-IR have also been demonstrated as useful and informative methods [22] and the application of high-temperature GC and inductively coupled plasma-atomic emission spectroscopy (ICP-AES) is also described [5]. [Pg.239]

When the system was cooled down the organic and aqueous phases separated out. The product was recovered by the evaporation of THF. Hydrolysis reactions were followed by FT-IR spectroscopy. [Pg.165]

Fourier-transform infrared (FT-IR) spectroscopy and small-angle X-ray (SAXS) and neutron (SANS) scattering studies have shown the existence of a further pressure induced gel phase in DPPC bilayers." " Pressure dependent NMR studies yielded complementary information on the pressure-induced gel phases. The gel state of DPPC bilayers shows a variation in lineshapes which depend on the particular pressure and temperature. The types of lineshapes seen in a high pressure investigation of dg2-DPPC by Jonas et al. are... [Pg.182]


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Applications of FT-IR Spectroscopy

Assignment of Adsorbed Species by FT-IR Spectroscopy

Combination of AFM and Photothermal FT-IR Spectroscopy

Diffuse reflectance FT-IR spectroscopy

FT spectroscopy

FT-IR photoacoustic spectroscopy

FT-IR reflection-absorption spectroscopy

Fourier transform infrared spectroscopy FT-IR)

Fourier-transformed infrared spectroscopy FT-IR)

Organic Compounds FT-IR Spectroscopy

Photoacoustic spectroscopy FT-IR-PAS)

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