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Mercury line emission spectrum

Continnous and line emission spectra. From the top down The continuous visible spectrum the line emission spectra for sodium (Na). hydrogen (H). and mercury (Hg). [Pg.136]

An emission spectrum for pure mercury obtained from a mercury lamp. It is easy to see that mixed sources, and higher energy excitation will produce very complex patterns of lines, demanding high quality optical... [Pg.287]

The emission spectrum for mercury shows that it has more spectral lines than the emission spectrum for hydrogen. [Pg.131]

The most frequently used lamp for UV curing processes is medium-pressure mercury lamp. Its emission spectrum can be used to excite the commonly used photoinitiators. Moreover, this type of lamp has a relatively simple design, is inexpensive, can be easily retrofitted to a production line, and is available in lengths up to 8 ft (2.5 m). Power levels in common use are in the range 40 to 240 W/cm, and even higher levels are available for special applications. ... [Pg.23]

Emission spectrum Radiation from an atom in an excited state, usually displayed as radiant power vs. wavelength. Each atom or molecule has a unique spectrum. The spectra can be observed as narrow line emission (atomic emission spectra) or as quasi-continuous emissions (molecular emission spectra). A mercury plasma emits both line spectra and continuous spectra simultaneously. [Pg.254]

Figure 6 shows the absorption curve for acetone superimposed upon the emission spectrum of a medium pressure mercury vapor lamp of the type commonly used in photochemical investigations. If the possibility of mercury photosensitization is neglected, it can be seen that the emission line in the mercury spectrum which will be most effective in photolysis is that at 3130 A., and, in fact, this line is frequently isolated by the... [Pg.152]

Wavelength accuracy. In order to evaluate the ability of each system to locate spectral lines, a preliminary wavelength calibration was carred out with the emission spectrum of a mercury pen lamp and then the peak maxima of several atomic lines from an iron hollow cathode lamp were located. The root mean square (RMS) prediction error, which is the difference between the predicted and the observed location of a line, for the vidicon detector system was 1.4 DAC steps. Because it is known from system calibration data that one DAC increment corresponds to 0.0125 mm, the absolute error in position prediction is 0.018 mm. For the image dissector, the RMS prediction error was 7.6 DAC steps, and because one DAC step for this system corresponds to 0.0055 mm, the absolute error in the predicted coordinate is 0.042 mm. The data in Table II represent a comparison of the wavelength position prediction errors for the two detectors. [Pg.75]

Emission Spectrum. Several sources are suitable for exciting the emission spectrum of I2. In previous editions of this text, the use of a low-pressure mercury discharge lamp was described, in which the green Hg line at 546.074 nm causes a transition from... [Pg.440]

In emission spectroscopy the molecule or atom itself serves as the somce of light with discrete frequencies to be analyzed. In some cases, such as Exp. 39, which deals with the emission spectrum of molecular iodine vapor, excitation by a monochromatic or nearly monochromatic laser or mercury lamp is utilized. For other cases, such as the emission from N2 molecules, electron excitation of nitrogen in a discharge tube provides an intense somce whose spectrum is analyzed to extract information about the electronic and vibrational levels. Such low-pressure (p < 10 Torr) line somces are available with many elements, and lamps containing Hg, Ne, Ar, Kr, and Xe are often used for calibration purposes. The Pen-Ray pencil-type lamp is especially convenient for the visible and... [Pg.619]

Very elegant experiments unequivocally proving the occurrence of electronic energy transfer were performed in 1922 and 1923 by Carlo and Franck [14], When a mixed vapor of mercury and thallium was irradiated with the mercury line at 253.67 nm, the emission lines of thallium could be observed in addition to the anticipated fluorescence spectrum of mercury. Since thallium cannot absorb 253.67-nm light, it must have been sensitized by the excited mercury atoms in order to produce the green fluorescence... [Pg.294]

Mercury s atomic emission spectrum is shown below. Estimate the wavelength of the orange line. What is its frequency What is the energy of an orange photon emitted by the mercury atom ... [Pg.147]

Mercury or xenon arc lamps are used. A schematic of a xenon arc lamp is given in Fig. 5.42. The quartz envelope is filled with xenon gas, and an electrical discharge through the gas causes excitation and emission of light. This lamp emits a continuum from 200 nm into the IR. The emission spectrum of a xenon arc lamp is shown in Fig. 5.43. Mercury lamps under high pressure can be used to provide a continuum, but low-pressure Hg lamps, which emit a line spectrum, are often used with filter fluorometers. The spectrum of a low-pressure Hg lamp is presented in Fig. 5.44. [Pg.372]

To verify this proposition to some extent, mercury fulminate was irradiated with a 75 mJ laser pulse, a value which is below the initiation energy threshold (for the used sample holder). The emission spectrum recorded 270 nsec after the start of the laser pulse does not reveal emission lines/bands or species different from those obtained after explosive irradiation [40], although some changes in the relative intensity of the emission lines were noticed. Although additional experiments to verify this proposal and to establish its limitations are needed, it is believed that the emission spectra of irradiated unconfined explosives give useful information about decomposition intermediates. This belief is supported by the observation of similar species in emission spectra recorded under various circumstances [14]. [Pg.664]

In figure 8 the emission spectrum of mercury fulminate is shown, recorded close to the sample s surface after irradiation with 248 laser light. All emission lines up to 600 nm can be assigned to Hg, CN, C2 and to the impurities, Na, K, Ca and Ca" . The emission beyond 600 nm has not been identified. [Pg.669]

In contrast to the low-pressure lamps (1—130 Pa) which primarily emit at the resonance line at A = 254nm, high-pressure lamps (lO —10 Pa) also produce numerous bands in the UV and VIS regions (Fig. 16). Table 3 lists the emission lines and the relative spectral energies of the most important mercury lamps (see also [44]). The addition of cadmium to a mercury vapor lamp increases the numbei of emission lines particularly in the visible region of the spectrum [45] so that it i. also possible to work at A = 326, 468, 480, 509 and 644 nm [46]. [Pg.22]


See other pages where Mercury line emission spectrum is mentioned: [Pg.456]    [Pg.456]    [Pg.121]    [Pg.3394]    [Pg.428]    [Pg.457]    [Pg.31]    [Pg.131]    [Pg.876]    [Pg.204]    [Pg.166]    [Pg.314]    [Pg.259]    [Pg.299]    [Pg.86]    [Pg.444]    [Pg.3035]    [Pg.321]    [Pg.3462]    [Pg.43]    [Pg.44]    [Pg.48]    [Pg.629]    [Pg.473]    [Pg.653]    [Pg.161]    [Pg.93]    [Pg.30]    [Pg.55]    [Pg.66]    [Pg.1199]   
See also in sourсe #XX -- [ Pg.3394 ]




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