Luminescence solubility

Molecule-based materials are bottom-up designed materials where the starting point is one or several molecules with some specific properties that will go through a synthetic process to give a bulk material with desired specifications as to magnetism, porosity, catalytic potential, luminescence, solubility, colour, etc. In order to achieve these properties, there may be a specific three-dimensional arrangement of the molecular building blocks that Is required. 

Recent work with multi-layer polymer LEDs has achieved impressive results and highlights the importance of multi-layer structures [46]. Single-layer, two-layer and three-layer devices were fabricated using a soluble PPV-based polymer as the luminescent layer. The external quantum efficiencies of the single-layer, two-layer, and three-layer devices were 0.08%, 0.55%, and 1%, respectively, with luminous efficiencies of about 0.5 hn/W, 3 lm/W, and 6 lm/W. These results clearly demonstrate improvement in the recombination current because of the increase in quantum efficiency. The corresponding increase in luminous efficiency demonstrates that the improvement in recombination efficiency was achieved without a significant increase in the operating bias. 

The product of the luminescence reaction of coelenterazine, coe-lenteramide, is soluble in methanol, butanol, ethyl acetate and ether, and shows a strong blue fluorescence in these solvents, although this compound is only slightly fluorescent in aqueous solutions. Coelen-teramide shows an absorption maximum at 332-333 nm (s 15,000) in methanol. 

Extraction and partial purification of photoprotein. The solubility and general luminescence characteristics of the S. luminosa photoprotein are similar to those reported for the S. oualaniensis photoprotein the protein is soluble in buffer solutions containing 0.6-1.0 M salt but not in solutions containing 0.1-0.2 M salt, and the luminescence is pH-dependent. In the extraction of S. oualaniensis,... 

The active luciferase in the soluble luminescence system occurs in two molecular sizes, 130 kDa and 35kDa. The 130 kDa luciferase is the native form and occurs in extracts made at pH 8, and if luciferase is extracted with a pH 6 buffer, 130 kDa luciferase is converted into 35 kDa luciferase by the action of a protease (Krieger and Hastings, 1968 Fogel and Hastings, 1971 Krieger et al., 1974). The 130 kDa species is considered the naturally occurring form. 

Requirements of Standards. The general requirements for luminescence standards have been discussed extensively (3,7-9) and include stability, purity, no overlap between excitation and emission spectra, no oxygen quenching, and a high, constant qtiantum yield independent of excitation wavelength. Specific system parameters--such as the broad or narrow excitation and emission spectra, isotropic or anisotropic emission, solubility in a specific solvent, stability (standard relative to sample), and concentration--almost require the standard to be in the same chemical and physical environment as the sample. 

Deng, D. W. Qin, Y. B. Yang, X. Yu, J. S. and Pan, Y. (2006). The selective synthesis of water-soluble highly luminescent CdTe nanoparticles and nanorods The influence of precursor Cd/Te molar ratio.. Cryst. Growth, 296,141-149. 

Two practical advantages of luminescence species engulfed in antenna dendrimer scaffolds are apparent, namely their miscibility with organic media (solvents or/and resins) and their ability to form thin films. For example the lanthanide-cored dendrimer complexes described in this chapter can be regarded as organic-soluble inorganic luminescers. 

The PBE dendron has a glass transition at about 40 °C and is soluble in various organic solvents (e.g., THF, acetone, toluene). It is therefore a moldable, thermoplastic, film-forming material. This practical feature is maintained for the lanthanide-cored dendrimer complexes. The complexes are partially miscible with poly(methyl methacrylate), affording transparent luminescence compositions by mixing in solvent. 

The PPhE bearing the PBE dendron as the repeating side chains is also soluble in THF, whereas the rigid main chain itself does not dissolve in any solvent. The blue-luminescence dendron-grafted rigid polymer forms thin films by spin coating [18]. 

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. 

Fackler, J.J., Grant, T.A., Hanson, B.E.and Staples, R.J. (1999) Characterisation of luminescent, homoleptic, three coordinate, water soluble Au(I) complex of trisulfonated triphenylphosphine (TPPTS) as the caesium salt, Cs8[Au(TPPTS)j]. 5.25H2O. Cold Bulletin, 31, 20-23. 

Mandal, A., Nakayama, J., Tamai, N., Biju, V. and Isikawa, M. (2007) Optical and dynamic properties of water-soluble highly luminescent CdTe quantum dots. J. Phys. Chem. B, 111, 12765-12771 Mandal, A. and Tamai, N. (2008) Influence of acid on luminescence properties of thioglycolic acid-capped CdTe quantum dots. J. Phys. Chem. C, 112, 8244-8250. 

N. A. and Liz-Marzan, L. M. (2004) Mechanism of strong luminescence photoactivation of citrate-stabilized water-soluble nanoparticles with CdSe cores./. Phys. Chem. B, 108,15461-15469. 

In this sub-subsection, the Er doping of amorphous silicon is discussed. The problem of limited solubility of Er in crystalline silicon has been circumvented. However, the electrical properties of pure a-Si are poor compared to c-Si. Therefore, hydrogenated amorphous silicon is much more interesting. Besides, the possibility of depositing a-Si H directly on substrates, i.e., optical materials, would make integration possible. Both low-pressure chemical vapor deposition (LPCVD) [664] and PECVD [665, 666] have been used to make the a-Si H into which Er is implanted. In both methods oxygen is intentionally added to the material, to enhance the luminescence. 

Demas J.N., DeGraff B.A., Xu W., Modeling of Luminescence Quenching-Based Sensors Comparison of Multisite And Nonlinear Gas Solubility Models, Anal. Chem. 1995 67 1377-1380. 

Fluorescent silica nanoparticles, called FloDots, were created by Yao et al. (2006) by two synthetic routes. Hydrophilic particles were produced using a reverse micro-emulsion process, wherein detergent micelles formed in a water-in-oil system form discrete nanodroplets in which the silica particles are formed. The addition of water-soluble fluorescent dyes resulted in the entrapment of dye molecules in the silica nanoparticle. In an alternative method, dye molecules were entrapped in silica using the Stober process, which typically results in hydrophobic particles. Either process resulted in luminescent particles that then can be surface modified with... 

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