Yellow emission

N is formed, and the process is accompanied by a peach-yellow emission which persists as an afterglow, often for several minutes after the discharge... 

Eckstein, J. W., et al. (1990). A time-dependent bacterial bioluminescence emission spectrum in an in vitro single turnover system energy transfer alone cannot account for the yellow emission of Vibrio fischeri Y-l. Proc. Natl. Acad. Sci. USA 87 1466-1470. 

The 3.5 ms lifetime of the yellow emission of Au3(p-tolN=COEt)3-CioFg is two orders of magnitude shorter than the lifetime of the octafluoronaphthalene phosphorescence which is observed at low temperature, thus indicating a gold... 

Dip the platinum loop in the solution and stick it in the flame. The result is a bright yellow glow. The color comes from two yellow emission lines that dominate the spectrum of sodium. The emission lines result from electrons dropping from the 3p to the 3s orbital. The two lines are very close to one another. The difference in energy is due to the slightly different energies of the electrons in the 3p orbital because of their spin. 

Wachter RM, Elsliger MA, Kallio K, Hanson GT, Remington SJ (1998) Structural basis of spectral shifts in the yellow-emission variants of green fluorescent protein. Structure 6 1267-1277... 

P-20 ZnCdS2 Ag+ ZnS, (ZnQ 715.AgQ 2g5)S2 Display tubes, phosphor is used for standard of comparison. Greenish-yellow emission (555 nm)... 

The staining of germinated pollen of Hippeastrum hybridum with colchicine demonstrates green-yellow emission of microtubules (better vision in black-white image) around nuclei of pollen grain (threads at the division of the nucleus) and spermium on the tip of the pollen tube, where spermium moves, as well as in some bridge sites of the tube (Fig. 10). The similar fluorescent allelochemicals may be also used as fluorescent dyes at the cellular diagnostics (Roshchina, 2005 b). 

The yellow flame of traditional oil burners is often surveyed by flame guards that react on the visible emission. More modern oil heaters use blue-burning flames. There, the carbon black of the combustion process is redirected to the combustion area for a more complete combustion, thus giving higher efficiency. With the reduced carbon black their yellow emission in the visible also vanishes, leaving an almost invisible flame, see Fig. 5.44. For these blue flames surveillance based on UV emission is preferable... 

J. Janssen and N. Lockyer independently discover helium from yellow emission line ( D3 ) in spectrum of prominence seen at eclipse. 

The same Suzuki methodology was used to synthesize a similar copolymer 446 [548], The polymer showed a solvent-dependent green-yellow emission (from 545 nm in THF to 565 nm in chloroform) as often observed for polar chromophores. The PL QE also varied with the solvent (from 11% in THF to 21% in decalin) but, in contrast to copolymer 445, no strong decrease in emission efficiency was observed in the solid state (4>p1 n= 13%) that could be attributed to the effects of substituents at the thiophene ring. LEDs based on 446 showed, for an ITO/PEDOT/446/Ca/Al architecture, a turn-on voltage of ca. 10 V with a maximum brightness of 340cd/m2 at 22 V and appreciable el = 0.14%. 

A significant suppression of the yellow emission band of LPPP was also achieved by dilution in PVK matrix, resulting in 2-3 times increase in EL efficiency, compared to the device prepared with neat LPPP (ITO/polymer/Al) [622]. 

Flame emission was monitored using fiber optic probes and either a photodiode detector for yellow emission from hot soot or a photo multiplier tube for violet emission from CH radicals (430 nm bandpass filter). 

Time-resolved luminescence spectroscopy of zircon revealed luminescence lines, which maybe confidentially ascribed to a Eu center (Fig. 4.38d). Usually they are hidden by a broad band yellow emission of zircon and may be detected only with a long delay time using its much longer decay time compared to yellow luminescence. 

In order to find the impurity responsible for the yellow emission, artificial Sn02 have been studied activated by different impurities such as Ti, Nb, Ta, W, Fe (Gaft et al. 1982). From crystallochemical positions such ions are capable of substituting for Sn. Nevertheless, the correlation of luminescence with... 

Thus, the addition of a few drops of acetone to a previously irradiated solid led to an intense yellow emission, visible to the human eye for a few seconds. This emission was the same as the lower energy emission detected in the solid state. Several other liquids such as chloroform, dichloromethane, toluene, methanol, hexane or even water produced the same phenomenon and the intensity of the emission depended... 

It is in this afterglow region where most of the light is emitted. In a pure hydrogen-air flame, virtually the only light emitted is from the OH radical, which is in the ultraviolet region of the spectrum, and therefore invisible. If hydrocarbons are present, then the blue, green, and yellow emissions by the radicals CH and C2 are visible, and possibly the incandescence of hot soot particles. 

Whereas 39 is not emissive at room temperature, despite the short Cu Cu distances, compound 39 exhibits in the solid state a bright orange-yellow emission at 531 nm after excitation at 350 nm, arising from a CC-excited state with mixed XMCT character. Figure 50 shows also that a second high-energy band is present with a weaker maximum at 420 nm. 

As consequence of this cuprophilic interaction, desolvated polymer 4T shows photoluminescence behavior. The authors attribute the observation of bright yellow emission at 420 nm after excitation at 320 nm to an CC-excited state with mixed XMCT character the term solvato-photoluminescence was coined for the off on behavior caused by the 41 —>4T transformation.161... 

Figure 26. Experimental photoluminescence quantum yields for Mn2+ CdS nanocrystals, plotted versus Mn2+ concentration (a) for the long-lived yellow emission from Figure 25 (b) for the shortlived red emission from Figure 25. The solid lines represent the proportion of particles with (a) 1 and (b) 2-5 Mn2+ dopant ions, as described by Eqs. 1 and 2. [Adapted from (82).]...

Crystals of Au lMeN = COMe)3 that display solvoluminescence show dual emission as seen in Trace B of Fig. 14, which was obtained at room temperature. There is a structured, short-lived (r 1 ps) emission at 446 nm and a broad, long-lived emission at 552 nm. The later decay can be fit by three decay curves with r 1.4, 4.4, and 31 sec. The yellow emission at 552 nm is readily detected by the human eye in a dark room for tens of seconds after photo irradiation of the crystalline solid. The extremely long lifetime of this yellow emission suggests that charge separation is occurring in the photo-irradiated solid. 

Since GaN materials contain a high density of extended defects (10 - 1010 cm 2), it is expected that the carrier and exciton recombination dynamics vary from sample to sample. Studies have revealed that the exciton lifetime is correlated with the yellow emission line at about 2.2 eV the stronger the yellow... 

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