High-resolution photoluminescence

Identification of amino- and nitro-substituted PAH may be effected by Shpol skii spectroscopy, a technique involving high resolution photoluminescence spectroscopy of the... 

A pulsed N2 laser (2 = 337.1 nm, rp = 8 ns, v = 1 kHz) and a CW HeCd laser (2 = 325 nm) were used for photoluminescence (PL) and lasing measurements. The monochromatized radiation of a Xe lamp (7exc 10"4 W/cm2) was used for PL excitation (PLE) spectra measurements. Low-excitation time-resolved PL measurements were performed at RT using the time-correlated single-photon counting method. X-ray diffraction analysis was performed with a high-resolution diffractometer (PANalytical s X Pert PRO MRD). 

The conclusion that can be drawn from the experiments just discussed is that, except for the very small particles, the photoluminescence of our Si nanocrystals, which are produced by CO2 laser-assisted pyrolysis of silane and which are gently oxidized in air under normal conditions, can be perfectly explained on the basis of the quantum confinement model, that is, by the radiative recombination of electron-hole pairs confined in the nanocrystals [15]. In order to obtain high quantum yields, the nanoparticles must be defect-free in particular, they must be perfectly monocrystalline and all dangling bonds must be passivated, for example by a silicon oxide layer. Indeed, high-resolution electron microscopy (HREM) studies have shown that our Si nanoparticles are composed of a perfect diamond-phase crystalline core and a surrounding layer of SiO [19]. 

Pedone V, Cercone K, Burrus R (1990) Activators of photoluminescence in calcile evidtaice from high resolution, laser excited luminescence spectrometry. Chem Geol 88 183-190 Platonov A (1979) Color of minerals. Naukova Dumka, Kiev (in Russian)... 

Fig. 3.21 Superimposed C Is and Pt 4f X-ray photoelectron images (top) and the Pt 4f high resolution X-ray photoelectron spectra corresponding to spots a and b bottom). Top image reprinted from Harada, Y., Li, X., Bohn, P. W., Nuzzo, R. G. Catalytic Amplification of the Soft Lithographic Patterning of Si. Nonelectrochemical Orthogonal Fabrication of Photoluminescent Porous Si Pixel Arrays. J. Am. Chem., Soc., 123, 8709 (2001). Copyright 2001 American Chemical Society...

Deep level transient spectroscopy (DLTS), photoacoustic spectroscopy (PAS), photoluminescence (PL), cathodoluminescence (CL), electron spin resonance (ESR), nuclear magnetic resonance (NMR), transmission electron microscopy (TEM), high-resolution electron microscopy (HREM)... 

The synthesized samples can be characterized by X-ray diffraction (XRD), Field Emission Scanning electron microscopy (FESEM), High Resolution Transmission electron microscopy (HRTEM), photoluminescence (PL) spectroscopy, UV-VIS spectroscopy Fourier transform infrared spectroscopy (FTIR), Raman spectroscopy, etc. 

Luminescence, in particular photoluminescence, constitutes a well-established discipline in analytical science where the cited hallmarks include remarkable sensitivity, wide dynamic range and low detection limits (-10under suitable conditions). These collective merits are often umivaled by other optical techniques, and hence its wide adoption in the life sciences for determining trace constituents in biological and environmental samples. Moreover, its fast response, high spatial resolution and remote sensing capabilities make it attractive for real-time analytical problems such as process manufacturing (process analysis or PAT) and field applications. ... 

Raman photoluminescence piezospectroscopy of bone, teeth and artificial joint materials has been reviewed by Pezzotti (2005) with emphasis placed on confocal microprobe techniques. Characteristic Raman spectra were presented and quantitative assessments of their phase structure and stress dependence shown. Vibrational spectroscopy was used to study the microscopic stress response of cortical bone to external stress (with or without internal damages), to define microscopic stresses across the dentine - enamel junction of teeth under increasing external compressive masticatory load and to characterise the interactions between prosthetic implants and biological environment. Confocal spectroscopy allows acquisition of spatially resolved spectra and stress imaging with high spatial resolution (Green etal., 2003 Pezzotti, 2005 Munisso etal., 2008). 

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