Micro Photoluminescence

Figure 7. Micro-photoluminescence spectra of the nanoneedle of Fig. 5 for D 790 nm at two different polarizer azimuth orientations shifted vertically for clarity. The modulation of the VIS band almost disappears when detecting the TE mode. Thus, the resonances are mainly TM polarized. The inset shows the ratio P = (Tm Te) (Tm + e), that visualizes the TM-WGMs as distinguishable peaks. The polarization effect has been found to be independent of the polarization of excitation.

Based on those propositions mentioned above, we tried to design a mesoporous material having micro crystalline wall by controlling the ratio of Q4 silicate species formed around TPA and Q2,3 silicate species interact with the micelles. To synthesize micro-mesoporous composite material through the control of Q2-3 and Q4 groups, two different templates were used and nucleation step of microporous material was introduced prior to the crystallization. And also we have attempted to monitor microenvironment of micro-mesoporous composite materials during the nucleation and crystallization steps using TG-DTA and photoluminescence with pyrene probe. 

Fig. 17 Photoluminescence (PL) of ZnS Mn + particles prepared by a conventional reaction at room temperature b conventional reaction with hydrothermal treatment c micro emulsion at room temperature d microemulsion with hydrothermal treatment, with an excitation intensity of 4 W/cm [143]...

Von Recum AF, Van Kooten TG (1996) The influence of micro-topography on cellular response and the implications for silicone implants. J Biomater Sci Polym Ed 7(2) 181-198 Wang Q, Ni H, Pietzsch A, Hennies F, Bao Y, Chao Y (2011) Synthesis of water-dispersible photoluminescent silicon nanoparticles and their Use in biological fluorescent imaging. J Nanopart Res 13(1) 405-413... 

Luchenko AI, Melnichenko MM, Svezhentsova KV (2007) Chemical modification of single - crystal silicon surface. J Optoelec Adv Mater 9 1431-1434 McCord P, Yau S-L, Bard AJ (1992) Chemiluminescence of anodized and etched silicon evidence for a luminescent siloxene-like layer on porous silicon. Science 257 68 Melnichenko MM, Svezhentsova KV, Shmyryeva AN (2005) Porous silicon upon multicrystalline silicon structure and photoluminescence. J Mater Sci 40 1409-1412 Melnikov VA, Astrova EV, Perova TS, Srigengan V (2008) Stain etching of micro-machined silicon structures. J Micromech Microeng 18 025019... 

Cancer cell cultures (HeLa and NIH-3 T3) impregnated with 0.1 g/L meso-PSi nanoparticles and exposed to 60 J/cm white light exhibited 45 % cell death, while controls containing no nanoparticles showed 10 % and 25 % cell death for HeLa and NIH-3 T3 lines, respectively. The dark control experiment yields <10% cytotoxicity for either cell type (Xiao et al. 2011). Micro-PSi nanoparticles were found to penetrate into cancer cells, resulting in 70 % cell death after illumination (Osminkina et al. 2011). Micro-PSi nanoparticles were also examined as SO photosensitizers and photoluminescent labels in bioimaging in vitro, and then they were proposed for application in cancer theranostics (therapy and diagnostics) (Osminkina et al. 2012). 

Hydrogenated amorphous silicon was formed by plasma decomposition of monosilane gas. The network has the dimension of close to 3. Polysilane alloy was formed by plasma decomposition of disilane gas.33 The network consists of a mixture of 1-dimensional polysilane and 3-dimensional silicon micro clusters.34 The effective network dimension is lower than that of amorphous silicon. Photoluminescence observations for various silicon-based materials are shown in Figure 14. The peak energy values of the photoluminescence spectra for amorphous silicon, polysilane alloy, hexyl-silicon network polymer and dihexylpolysilane are 0.8, 1.2, 2.8 and 3.3 eV, respectively. This result confrrms that a wide continuous spectra range from ultraviolet to infrared can be covered by the luminescence spectra of silicon based polymers. 

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