White-light luminescence

Kaukonen AM, Laitinen L, Salonen J, Tuura J, Heikkila T, Limnell T, Hirvonen J, Lehto VP (2007) Enhanced in vitro permeation of furosemide loaded into thermally carbonized mesoporous silicon (TCPSi) microparticles. Eur J Pharm Biopharm 66 348 Kayahan E (2010) White light luminescence from annealed thin ZnO deposited porous silicon. J Lumin 130 1295... 

Undoped, Mn, and Pr-doped ZnS namopartides synthesized by wet chemiral mdhod were optically annealed in air or vacuum. PL emission inoeas with annulling time. This increase is attributed to the photo-oxidation, enhancanent in the crystal quality, and diffiision of the luminescent ions. PL intensity of nanoparticles annealed in air increased more significantly due to the photo-oxidation compared with the nanoparticles annealed in vacuum. Mn and Pr-codoped ZnS nanoparticles emitted white light due to the effects of dopants. The optical annealing enhanced the emission intensity. 

Dutta DP, Ghildiyal R, Tyagi AK (2009) Luminescent properties of doped zinc aluminate and zinc gallate white light emitting nanophosphors prepared via sonochemical method. J Phys Chem C 113(39) 16954-16961... 

Blue luminescent materials for organic electroluminescent devices White light-emitting organic electroluminescent devices Blue organic electroluminescent devices... 

Fig. 6 Luminescent profile of Au23 cluster before (pink trace) and after (orange trace) phase transfer. Emission of the cluster enhances considerably after phase transfer. Photographs of the aqueous-toluene mixture containing the cluster before and after phase transfer under white light (A and B, respectively) and UV light (C and D, respectively). In C, only the interface is illuminated as the UV radiation is attenuated as the sample was irradiated from the top [15]...

The optical setup for time-resolved micro-luminescence measurements is based around an Axiotech 100 HD Zeiss microscope, modified to allow laser injection and fluorescence collection. The sample is observed either under transmission or reflection of polarized white light, or under UV illumination (HBO lamp). A set-up consisting of a dichroic mirror, for the selection of the excitation wavelength, and an objective (Epiplan Neofiuar obj. > 350 nm Ealing/Coherent reflection obj. < 350 nm) is used to focus the laser beam on the sample (spatial resolution over 5 pm with a x50 objective). The lim-... 

When an intense pulse of monochromatic laser light is focussed on a transparent liquid or solid, there is an emission of white light over a wide continuous spectral range. This process is known as self-phase modulation . We will not consider its physics. For our purpose it is important to note its photochemical implications. On the one hand, this pulse of white light can be used to provide a probe light in ps and fs flash photolysis (sections 8.1 and 8.2). On the other hand, it can be a source of stray light in some luminescence measurements. This comes as a surprise to many users of lasers for luminescence kinetics measurements, but it is an unavoidable problem. 

Finally, in a novel application, some uniquely structured hexapyrrolidine derivatives of C60 with Th and D3 molecular symmetries have been synthesized and characterized by analytical methods and x-ray crystallography [260]. This work revealed strong luminescence, indicative of photophysical properties that are unusual in comparison with other fullerene derivatives. Therefore, the hexapyrrolidine adduct was utilized as a chromophore in the fabrication of a white light organic LED [261]. 

Other groups reported the solution synthesis of a cerium-doped inorganic phosphor library (73) to optimize their structure as luminescence down-converters in white Light Emitting Diodes (LEDs) and the use of cathodoluminescence (CL) (74) to identify... 

On the other hand, imique physical properties and potential applications of nanoscaled lanthanide-doped LaFa have been discussed in many reports. For instance, van Veggel et al. reported the bright white light through up-conversion of a single near-infrared source by thin film of LaFaiYb, Eu /Er /Tm NPs (Figure 65) (Sivakumar et al., 2005). And the silica films with (Er +, Nd +, and Ho ) doped LaFs NPs possessed the visible white luminescence (Sudarsan et al., 2005). 

Luminescent lighting started even before the Second World War. The ultraviolet radiation from a low-pressure mercury dischaige is converted into white light by a phosphor layer on the inner side of the lamp tube. These lamps are much more efficient than the incandescent lamp a 60 W incandescent lamp yields 15 Im/W, a standard 40 W luminescent lamp 80 Im/W. 

A luminescent lighting lamp has to emit white light, so that the sun, our natural lighting source, is imitated. The sun is a black body radiator, so that its emission spectrum obeys Planck s equation ... 

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