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0.492–470sh on Dy side of longer wave-lengths (crest 0.490)
0.500–.475
0.500 (diffuse)
Under flame excitation there was a brief glow, green in color, during which the bands recorded in the table flashed up and disappeared. This was followed by a red glow the spectrum of which consisted of two new bands i.e. 0.650μ–0.600μ (Eu or Sin); 0.525μ–0.500μ (Eu).
This band which occurs in Tables 2 and 4, is tentatively assigned to samarium since it coincides with Urbain’s Sm band of that wave-length. It falls within the Europium group, however, extending from 0.637μ to 0.635μ and may be a composite of 0.625μ and 0.637μ (Urbain).
Table 5
Thorium oxide activated by neodymnium.
Excitation
Cathode
H flame
Color
purplish fades rapidly
yellow, then red
Spectrum
0.590–0.575 Dy (crest at 0.580)
0.575 (ill defined)
0.575–0.500 (diffuse)
0.550 d Tb
0.520 d Eu
0.490–0.480 Dy
Table 6
Calcium oxide activated by praseodymium.
Excitation
Cathode
H flame
U.V. spark
Color
Bluish
Orange
Orange-red
Spectrum
0.640–0.630 Sm
0.630
0.650
0.620 Eu
0.620
0.580–575 Dy
0.550–545 Tb
0.550–547
0.530–510 Eu
0.530
Table 7
Aluminum oxide activated by terbium.
Temp. C
Brightness cp/cm2
Temp. C
Brightness cp/cm2
A red glow just visible at 477° was replaced by green at 457°.
398°
0.0000724
133°
0.000389
378°
0.00110
124°
0.000209
The latter persisted at all lower temperatures with slight changes of hue.
0.492–470sh on Dy side of longer wave-lengths (crest 0.490)
0.500–.475
0.500 (diffuse)
Under flame excitation there was a brief glow, green in color, during which the bands recorded in the table flashed up and disappeared. This was followed by a red glow the spectrum of which consisted of two new bands i.e. 0.650μ–0.600μ (Eu or Sin); 0.525μ–0.500μ (Eu).
This band which occurs in Tables 2 and 4, is tentatively assigned to samarium since it coincides with Urbain’s Sm band of that wave-length. It falls within the Europium group, however, extending from 0.637μ to 0.635μ and may be a composite of 0.625μ and 0.637μ (Urbain).
Table 5
Thorium oxide activated by neodymnium.
Excitation
Cathode
H flame
Color
purplish fades rapidly
yellow, then red
Spectrum
0.590–0.575 Dy (crest at 0.580)
0.575 (ill defined)
0.575–0.500 (diffuse)
0.550 d Tb
0.520 d Eu
0.490–0.480 Dy
Table 6
Calcium oxide activated by praseodymium.
Excitation
Cathode
H flame
U.V. spark
Color
Bluish
Orange
Orange-red
Spectrum
0.640–0.630 Sm
0.630
0.650
0.620 Eu
0.620
0.580–575 Dy
0.550–545 Tb
0.550–547
0.530–510 Eu
0.530
Table 7
Aluminum oxide activated by terbium.
Temp. C
Brightness cp/cm2
Temp. C
Brightness cp/cm2
A red glow just visible at 477° was replaced by green at 457°.
398°
0.0000724
133°
0.000389
378°
0.00110
124°
0.000209
The latter persisted at all lower temperatures with slight changes of hue.