Cathodoluminescence intensity

Filippelli GM, Delaney ML (1992a) Similar phosphoras fluxes in ancient phosphorite deposits and a modem phosphogeitic enviromnent. Geology 20 709-712 Filippelli GM, Delaney ML (1992b) Quantifying cathodoluminescent intensity with an on-line eamera and exposure meter. J Sediment Petrol 62 724-725... 

Donor and acceptor levels are the active centers in most phosphors, as in zinc sulfide [1314-98-3] ZnS, containing an activator such as Cu and various co-activators. Phosphors are coated onto the inside of fluorescent lamps to convert the intense ultraviolet and blue from the mercury emissions into lower energy light to provide a color balance closer to daylight as in Figure 11. Phosphors can also be stimulated directly by electricity as in the Destriau effect in electroluminescent panels and by an electron beam as in the cathodoluminescence used in television and cathode ray display tubes and in (usually blue) vacuum-fluorescence alphanumeric displays. 

Spatial information about a system can be obtained by analyzing the spatial distribution of PL intensity. Fluorescent tracers may be used to image chemical uptake in biological systems. Luminescence profiles have proven useftil in the semiconductor industry for mapping impurity distributions, dislocadons, or structural homogeneity in substrate wafers or epilayers. Similar spatial infbrmadon over small regions is obtained by cathodoluminescence imaging. 

In the cathodoluminescence (CL) technique in the EM, the wavelength of light emitted by selective electron stimulation can be directly related to the local band-gap energy of the catalyst material, and the intensity of the signal to the... 

Wurtz-synthesized PMPS was selected as the material to be studied when subjected to cathodoluminescence (CL).98 The CL method of the study of PMPS is based on the measurement of CL intensity of emitted light after its passage through the specimen, as shown in Figure 20. For the PMPS degradation measurements, electron beam energy of 10k eV was used. The PL emission spectrum consists of two emission bands. The maximum of the... 

Figure 9. (a) - The dependence of integral intensity of li -band of solid Ar on temperature and photoexcitation energy, (b) - The dependence of integral intensity of W and A bands on energy of electrons in cathodoluminescence of solid Ar. 

FIGURE 6 Cathodoluminescence spectra obtained in the defective area of the crystal which appeared yellow in an optical microscope (a) and in the transparent area of the crystal (b). Note changes in the intensities of the yellow luminescence peak (2.4 eV) and band to band luminescence (3.5 eV). 

The given model is confirmed by the application of green emission intensity in low voltage cathodoluminescent phosphors, single erystals and ZnO films doped with Cu. ... 

The cathodoluminescence spectra of heavily B-doped (111) coalesced films on Pt(lll) had an edge emission band at 5.0 eV at room temperature [385, 435]. In Figure 13-20 [435], B-doped films were synthesized by MPCVD with B/C = 3300 ppm in the source gas. When the film thickness was 1.8 pm, there was an intense band A in the wavelength region of 400 to 600 nm in addition to a weak band at 248 nm (5.0 eV). When the film thickness was increased to 16 pm, band A entirely disappeared, and the CL spectrum consisted of the 248-nm band only. The major difference between the two films was that the 1.8-pm thick film consisted of (11 l)-oriented diamond grains, while the (111) faces were significantly... 

Fig. 7. (A) Blocky zoned meteoric calcite cement (type I) filling mouldic pore microcrystalline type II calcite (white arrow). Note intense bioclast replacement and loose packing (packing proximity = 36%k uncrossed polars. (B) Same field of view observed with cathodoluminescence type I calcite presents sharp CL zonation (black arrow), whereas type II calcite shows CL microzoning (white arrow). Note the high content of K-feldspars and plagioclase. Quartz grains do not show luminescence. AB-1 well 3244.45 m oil zone.

The PL, CL (cathodoluminescence), TL and PSL spectra of Sm doped Y2Si05 and of Sm +- and Tb -codoped Y2Si05 was studied by Meiss et al. (1994a). Figure 34 shows TL spectra of Y2Si05 Sm (0.02) and those of phosphors codoped by 0.1 and 0.001 Tb in curves 1 to 3, respectively. The spectra were taken at 350 K after X-iriadiation. The spectrum in curve 1 is characteristic of Sm, and those with 0.1 Tb (curve 2) and with 0.001 Tb (curve 3) give mainly Tb emission. The PSL of the X-irradiated phosphor obtained by illumination in the 380 nm band gives two intense PSL bands, at 650 and... 

K. Maeda, K. Nakagawa, S. Takeuchi, K. Sakamoto, Cathodoluminescence studies of dislocation motion in Ob—VIb compounds deformed in SEM, J. Mater. Sci. 16 (1981) 927—934. S. Sadakuni, J. Miurata, K. Yagi, Y. Sano, K. Arima, A.N. Hattori, T. Okamoto, K. Yamauchi, Influence of the UV tight intensity on the photoelectrochemical planarization technique for gallium nitride. Mater. Sci. Forum 645 (2010) 795—798. 

A system in which the interdiffusion was much more extensive was studied by Kriven and Risbud, who studied the reaction between copper and cordier-ite glass ceramics. They used cathodoluminescence to observe the intensity of the fluorescence from the Cu ions that diffused into the glass. Quantitatively, electron microprobe data indicated that the copper concentration 100 p,m from the interface was 7 atom %, although the backscattered electron image in the SEM did not indicate the presence of Cu particles, thus confirming the presence of Cu. ... 

The book deals mainly with theoretical approach, experimental results and their interpretation of laser-induced time-resolved spectroscopy of minerals in the wide spectral range from 250 to 2000 nm, which enables to reveal new luminescence previously hidden by more intensive centers. Artificial activation by potential luminescence centers has been accomplished in many cases, which makes the sure identification possible. The mostly striking example is mineral apatite, which has been extremely well studied by many scientists using practically all known varieties of steady-state luminescence spectroscopy photoluminescence with lamp and laser excitations. X-ray excited luminescence, cathodoluminescence, ionolumi-nescence and thermoluminescence. Nevertheless, time-resolved spectroscopy revealed that approximately 50 % of luminescence information remained hidden. The mostly important new information is connected with luminescence of trivalent... 

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