Spectrum sodium vapor

Light of wavelength 589 nanometers falls in the yellow portion of the visible region of the electromagnetic spectrum. The characteristic yellow glow of sodium vapor lamps used to illuminate many highways results from this particular emission. 

Finally, chemical activation has also been used to produce O J ions. When NaY heated previously in sodium vapor was exposed to oxygen, the red material became instantly white, the EPR spectrum of Na2+ centers disappeared, and a new signal appeared with gZI = 2.077 which was identified as 02 adsorbed at a Na+ ion (272). This is in contrast to OJ produced in NaY... 

The prominent yellow line in the spectrum of a sodium vapor lamp has a wavelength of 590 nm. What minimum accelerating potential will excite this line in an electron tube containing Na vapor ... 

Figure 4. Experimental spectrum of the reduced absorption coefficient k/[NaP, from Ref. 12. The spectrum was constructed from absorption spectra measured for sodium vapor pressures in between 100 and 1000 torr. The error bar indicates the absolute accuracy of this procedure (relative errors are considerably smaller). The Na nonresonance lines and the K and Cs resonance lines (see Fig. 2) were omitted.

Figure 28-2 (a) Partial absorption spectrum for sodium vapor. 

Liquid samples are applied to the slide surface as 200 pi drops in 50 mM pH 7 sodium phosphate buffer (NaPi) with the exception of GB, which is in deionized water. Excess liquid is blotted away from the slide surface and a transmission spectrum collected. Vapor phase samples are applied by directing a gas stream across the slide surface. The difference spectrum shown in Figure 1 is used to facilitate analysis of the changes in the absorbance spectrum. It is calculated as the point-by-point subtraction of the pre-exposure absorbance spectrum from the post-exposure absorbance spectrum. 

FIGURE 35 Example of high-resolution spectrum in sodium vapor obtained with two-photon Doppler-free spectroscopy. [Reproduced from Bloembergen, N., and Levenson, M. D. (1976). Doppler-free two-photon absorption spectroscopy. In High Resolution Laser Spectroscopy (K. Shimoda, ed.), p. 355, Springer, New York.l... 

An emission spectrum is produced when atoms in an excited state emit photons characteristic of the eiement as they return to iower energy states. The characteristic colors of fireworks and sodium-vapor streetlights are due to one or a few prominent lines in the emission spectra of the atoms present. 

When sodium vapor is excited by one of the D-lines, the fluorescence spectrum is known to exhibit another line of an intensity increasing with the efficiency of collisional mixing... 

Fig. 5.7 (a) The absorption speotrum of sodium vapor, oontaining Na2 moieouiesand Na atoms. The sharp iine is the atomic transition. (b) The absorption spectrum of sodium adsorbed on a sapphire surface normaiized to... 

Although Cojan was the first to observe spectral narrowing in SR, systematic studies started much later (Woerdman and Schuurmans 1975). The reflectivity at a glass-sodium vapor interface near the sodium Di and D2 lines was measured for different vapor densities. At low sodium densities the resolution of the hyperfine doublet splitting clearly indicated a considerable spectral narrowing as compared to the Doppler width. With an increasing sodium density the hyperfine structure of the SR spectrum was smeared out. When the... 

Problem 7.3. An evanescenf wave is excited by a laser beam striking the prism-sodium vapor interface. The laser beam is resonant to the 3Si/2 — 3P3/2 transition (A = 589 nm, the natural linewidth is 7n = 27T x 10 MHz). Estimate the angle of incidence beyond which the fluorescence spectrum excited by the evanescent wave is sensitive to the change of the excited state population in vapor-surface scattering. Assume the index of refraction of the prism to be tip = 1.5 and the vapor temperature to be T = 300 K. 

High-pressure sodium vapor lamps are used in street lighting. The two brightest lines in the sodium spectrum are at 589.00 and 589.59 run. What is the difference in energy per photon of the radiations corresponding to these two lines ... 

Figure 8.4a shows a portion of the ultraviolet spectrum of benzene in three media (1) heptane, (2) water, and (3) 0.4 M aqueous sodium dodecyl sulfate. It is not the prominent peaks in these spectra that interest us, but rather the small bands located 3.6 nm on the long-wavelength side of the major features. This band is absent in benzene vapor, but is present with variable intensity in solutions. Accordingly, it is described as a solvent-induced band with an intensity that depends on the polarity of the solvent. 

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