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Spectroscopy frequency-modulation

Votsmeier M, Song S, Davidson D F and Hanson R K 1999 Sensitive detection of NH2 in shock tube experiments using frequency modulation spectroscopy int. J. Chem. Kinetics 31 445-53... [Pg.2149]

Some very high resolution or ultrasensitive spectroscopies emerging as of ca 1996 were beam spectroscopy, multiphoton absorption and ionisation, and frequency-modulation spectroscopy (8). Most of these were used primarily for laboratory research as of the mid-1990s, but eventual appHcation to analytical or sensor appHcations is expected. [Pg.321]

Frequency-Modulation Spectroscopy. Frequency-modulation spectroscopy (tins) is a high sensitivity null-background infrared technique for measuring absorbances down to 10 with fast acquisition speeds. Fms involves frequency-modulating a laser source at COq to produce a carrier frequency having sidebands at cJq where is an integral multiple of the modulation frequency. Dye lasers and many other single-line sources can... [Pg.321]

Bjorklund, G.C. Frequency modulation spectroscopy a new method for measuring weak absorptions and dispersions. Opt. Lett. 1980, 5 (1), 15-17. [Pg.1976]

Silver, J.A. Frequency-modulation spectroscopy for trace species detection theory and comparison among experimental methods. Appl. Opt. 1992, 31 (6), IQl-lYl. [Pg.1976]

Ye J, Ma L-S and Hall J L 1996 Sub-Doppler optical frequency reference at 1,064 mm by means of ultrasensitive cavity-enhanced frequency modulation spectroscopy of a C2HD overtone transition . Opt. Lett., 21, 1000 - 2... [Pg.467]

Frequency modulation spectroscopy as a method to detect first-order susceptibilities in visible spectroscopy was first described by Bjorklund [58] and Hall et al. [59], and used by Bjorklund and Levenson [60] to observe hyperfine splitting in I2. Since then, it has been used to obtain spectra of transient species such as HCO, ND4, and HOz [61-64], Photodissociation studies using FM and absorption spectroscopy have been done by the group at Brookhaven National Laboratory [65-68], This chapter will concentrate on their particular methodology. [Pg.295]

G.C. Bjorklund, Frequency-modulation spectroscopy A new method for measuring weak... [Pg.681]

Direct absorption (frequency-modulation spectroscopy with secondary modulation)... [Pg.12]

Y (668), external cavity diode laser (ECDL). high frequency modulation spectroscopy A1 (394), second harmonic generation (SHG) of ECDL... [Pg.742]

As a final method for sensitive detection of saturation spectroscopy signals we will mention frequency modulation spectroscopy [9.183]. Here a frequency modulation is electro-optically imposed on a narrow-band laser beam of frequency Uq generating side-bands The phase factors... [Pg.293]

Frequency-modulation spectroscopy can also be used for sensitive absorption measurements using pulsed lasers [9.184]. The sidebands are then generated by microwaves ( 10GHz) to separate them from the rather broad-band pulsed radiation. Small differential absorptions from, e.g., pressure-broadened molecular transitions, can be detected. Other extremely sensitive laser absorption spectroscopy techniques have been described in [9.185,186]. [Pg.293]

M. Gehrtz, G.C. Bjorklund, E.A. Whittaker Quantum-limited laser frequency-modulation spectroscopy. J. Opt. Soc. Am. B2, 1510 (1985)... [Pg.380]

N.H. Tran, R Kachru, P. Pillet, H.B. van Linden van dem Heuvell, T.F. Gallagher, J.P. Watjen Frequency-modulation spectroscopy with a pulsed dye laser Experimental investigations of sensitivity and useful features. Appl. Opt. 23, 1353 (1984) Appl. Opt. 25, 510 (1986)... [Pg.380]

It has been shown that FM techniques are capable of measuring absorption signals down to the shot-noise limit (caused by the number fluctuations for the discrete photons), wliich frequently means, that absorptive signals of 1 part in 10 or 10 are detectable. Frequency modulation spectroscopy is described and discussed in [10.85]. [Pg.412]

Fig. 10.21. Arrangements for frequency modulation spectroscopy with diode lasers. In (a) low frequencies are employed and the term wavelength modulation spectroscopy pertains. In (b) high frequencies are used and discrete components replace the lock-in amplifier [10.84]... Fig. 10.21. Arrangements for frequency modulation spectroscopy with diode lasers. In (a) low frequencies are employed and the term wavelength modulation spectroscopy pertains. In (b) high frequencies are used and discrete components replace the lock-in amplifier [10.84]...
Fig. 10.22. Sideband generation in high-frequency modulation spectroscopy and resulting imbalance when one of the sidebands is absorbed by a gas [10,84]... Fig. 10.22. Sideband generation in high-frequency modulation spectroscopy and resulting imbalance when one of the sidebands is absorbed by a gas [10,84]...
Laboratory trace gas monitoring Discuss and compare the following methods optoacoiistic spectroscopy, cavity ring-down spectroscopy and frequency modulation spectroscopy. [Pg.466]

P. Kauranen, H.M. Hertz, S. Svanberg Tomographic imaging of fluid flows by the use of two-tone frequency modulation spectroscopy. Opt. Lett. 19, 1489 (1994)... [Pg.554]

See other pages where Spectroscopy frequency-modulation is mentioned: [Pg.423]    [Pg.423]    [Pg.117]    [Pg.117]    [Pg.117]    [Pg.1971]    [Pg.1976]    [Pg.28]    [Pg.321]    [Pg.15]    [Pg.681]    [Pg.13]    [Pg.378]    [Pg.918]    [Pg.918]    [Pg.281]    [Pg.412]   
See also in sourсe #XX -- [ Pg.13 ]

See also in sourсe #XX -- [ Pg.293 ]



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