Photoluminescence characterized

N. Chi, D. L. Philips, and K. Y. Chan, In situ photoluminescence characterization of porous silicon formation. Thin Solid Films 342, 142, 1999. 

Park WJ, Jung MK, Kang SM, Masaki T, Yoon DH (2008) Synthesis and photoluminescence characterization of Ca3Si207 Eu as a potential green-emitting white LED phosphor. J Phys Chem Solids 69 1505-1508... 

Yamamoto D, et al. Synthesis and photoluminescence characterization of dendrimer-encapsulated CdS quantrrm dots. Colloids Surf A 2012 411 12-7. 

For applied work, an optical characterization technique should be as simple, rapid, and informative as possible. Other valuable aspects are the ability to perform measurements in a contactless manner at (or even above) room temperature. Modulation Spectroscopy is one of the most usehil techniques for studying the optical proponents of the bulk (semiconductors or metals) and surface (semiconductors) of technologically important materials. It is relatively simple, inexpensive, compact, and easy to use. Although photoluminescence is the most widely used technique for characterizing bulk and thin-film semiconductors. Modulation Spectroscopy is gainii in popularity as new applications are found and the database is increased. There are about 100 laboratories (university, industry, and government) around the world that use Modulation Spectroscopy for semiconductor characterization. 

In this study, we report on the GaN nanorod growth by HOMVPE technique with or without using a new precursor, tris(N,N-dimethyldithiocarbamato)gallium(III) (Ga(mDTC)3). The structural and optical properties of GaN nanorods were characterized by x-ray diffraction (XRD), scanning electron microscopy (SEM), and photoluminescence (PL). 

Assefa, Z Forward, J.M., Grant T.A., Staples, R.J., Hanson, B.E., Mohamed, A.A. and Fackler, J.P. Jr (2003) Three-coordinate, luminescent, water-soluble gold(l) phosphine complexes structural characterization and photoluminescence properties in aqueous solution. Inorganica Chimica Acta, 352, 31 5. 

A tetrameric structure with the Zn40 core can also be formed with the 7-azaindolate ligand, [Zn40(C7H5N2)6], and has been structurally characterized. The tetramer displays intense photoluminescence at 448 nm in the solid state and 425 nm in acetonitrile with a lifetime and quantum yield of 0.1 ps and 0.17 ps respectively.280... 

The preparation of ZnSe materials is an area of interest and study. The coordinating ability of the solvent used in the solvothermal synthesis of zinc selenide was demonstrated to play an important role in the nucleation and growth of nanocrystalline ZnSe.604 Thermolysis of bis [methyl( -hexyl)di-seleno]carbamato]zinc gave highly monodispersed particles characterized by electronic spectroscopy, photoluminescence, X-ray diffraction, and electron microscopy.605... 

More than half of the members of this family have been structurally characterized and the Au-C distances correlated with the donor ability of the /rchemical shifts of 13C resonances in the NMR spectra. According to these results, the /rcarbene ligand appears to be comparable to that of triphenylphosphite P(OPh)3. Owing to the bulkiness of the lBu substituents, the complexes are not aggregated in the crystals. By contrast, the corresponding methyl-substituted compounds are aggregated to form chains via aurophilic contacts and are photoluminescent.18... 

One problem with methods that produce polycrystalline or nanocrystalline material is that it is not feasible to characterize electrically dopants in such materials by the traditional four-point-probe contacts needed for Hall measurements. Other characterization methods such as optical absorption, photoluminescence (PL), Raman, X-ray and electron diffraction, X-ray rocking-curve widths to assess crystalline quality, secondary ion mass spectrometry (SIMS), scanning or transmission electron microscopy (SEM and TEM), cathodolumi-nescence (CL), and wet-chemical etching provide valuable information, but do not directly yield carrier concentrations. 

Figure 11.2. Nanowire electronic and optical properties, (a) Schematic of an NW-FET used to characterize electrical transport properties of individual NWs. (inset) SEM image of an NW-FET two metal electrodes, which correspond to source and drain, are visible at the left and right sides of the image, (b) Current versus voltage for an n-type InP NW-FET. The numbers inside the plot indicate the corresponding gate voltages (Vg). The inset shows current versus Vg for Fsd of 0.1 V. (c) Real-color photoluminescence image of various NWs shows different color emissions, (d) Spectra of individual NW photoluminescence. All NW materials show a clean band-edge emission spectrum with narrow FWHM around 20nm. (See color insert.)...

Because of the high sensitivity of Ti-containing luminescence centers to their local environments, photoluminescence spectroscopy can be applied to discriminate between various kinds of tetrahedral or near-tetrahedral titanium sites, such as perfectly closed Ti(OSi)4 and defective open Ti(OSi)3(OH) units. Lamberti et al. (49) reported an emission spectrum of TS-1 with a dominant band at 495 nm, with a shoulder at 430 nm when the sample was excited at 250 nm. When the excitation wavelength was 300 nm, the emission spectrum was characterized by a dominant band at 430 nm with a shoulder at 495 nm. These spectra and their dependence on the excitation wavelength clearly indicate the presence of two slightly different families of luminescent Ti species, which differ in their local environments, in agreement with EXAFS measurements carried out on the same samples. 

As expected, the coordination of Pt markedly influences the photophysical characteristics of the PPE. The photoluminescence is efficiently quenched, and the absorption maximum in the visible regime experiences a hypsochromic shift. The charge-carrier mobility of different EHO-OPPE-Pt samples was determined by TOE measurements as described above for the neat EHO-OPPE. The shape of the photocurrent transients of all EHO-OPPE-Pt samples was similar to those shown in Figs. 6 and 7 for the neat EHO-OPPE. This indicates that these organometallic conjugated polymers networks are also characterized... 

FRET interactions are typically characterized by either steady-state or transient fluorescence emission signals from the donor or acceptor species. Efficient nonradiative energy transfer results in donor PL loss associated with acceptor gain in photoluminescence intensity (if the acceptor is an emitter). The rate of this energy transfer is related to the intrinsic lifetime of the isolated donor and depends strongly on the donor-acceptor separation distance ... 

Steady-state photoluminescence spectra of natural garnet were connected with a Cr " broad emission band peaking at 880 nm (Tarashchan 1978). Two strong bands, one in the yellow, and the other in the red characterize CL spectra of natural hydrogrossular. The first band at 590 nm was ascribed to Mn " substituting for Ca ". The red one extends into the NIR and has narrow peaks at 689,701 and 717 nm and was not interpreted (Ponahlo 2000). 

Mineral eosphorite has been studied by Vergara et al. (1990). The crystal structure of eosphorite contains two kind of octahedra. One of these is composed of Mn04(0H)2 sharing opposite 0-0 edges and the other of A102(0H)2(H20)2 sharing opposite H2O corners. Absorption spectra are characterized by a number of bands, which have been associated with transitions of Mn ". All photoluminescence was connected with Cr ions (Fig. 4.60). 

In 1958, the first SiC conference was held in Boston, Massachusetts. However, after this, the interest in SiC rapidly declined and the 1960s and 1970s are characterized by a low interest in SiC. Research was still ongoing, mainly in the former Soviet Union. In the United States, the work done by Westinghouse and the University of Pittsburgh is primarily notable. Indeed, the photoluminescence studies made by Choyke, Patrick, and Hamilton are still very relevant and often cited [21]. 

The experimental data presented show that sNPS can be used as transducers, which are stable for a long time after the construction of an immune biosensor. The specific immune complex formed on the sNPS surface may be registered by measuring its photoluminescence or photoconductivity. Such immune biosensors can be applied for control of T2 mycotoxin. The biosensors developed are sensitive and simple and allows for rapid analysis and analysis in field conditions. This approach may be applied for detection of any biochemical substances which can form an immune complex. Further investigations should be directed towards studying the mechanism of the biochemical signal detection by the sNPS and characterization of all the steps of analysis. 

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