Fluorescent materials perylenes

There are some optical SO, sensors which utilize a change of photo transmittance caused by the interaction of SOj with photoactive material[54] and a quenching of fluorescence from fluorescent materials like p3nrene-perylene charge transfer couple due to SO adsorption[55]. These sensors, however, have rather low sensitivity to SO, and are considered not to be suitable for environmental monitoring. 

Discotic derivatives of perylene have been prepared by Mullen and coworkers [99]. The discotic mesophase behaviour of these highly fluorescent materials is quite unusual because the molecules have low symme-... 

Precursor family 27 with a perylene sub-unit were prepared due to their fluorescent properties and their photostability. Grafting of the perylene unit with —(CH2)3Si(OR)3 arms (Section m.B) allows their solubility to be increased and thus to prepare materials... 

Fig. 10 (a) Molecular stmcture of N,iV -bis-(2 -ethylhexyl)perylene-3,4,9,10-tetracarbox-yldiimide (EE-PTCDI). (b) Fluorescence spectra of a LLDPE/EE-PTCDI blend film containing 0.1 wt% EE-PTCDI before and after uniaxial deformation to different draw ratios (Dr), (c) Picture of the same material in which the center portion has been uniaxially deformed to a draw-ratio of 4. The image was taken under excitation with ultraviolet light, (b, c) adapted with permission from [52]. Copyright 2008 American Chemical Society... 

Polycyclic aromatic hydrocarbons (PAHs) are produced through the incomplete combustion of various materials. Air-suspended particulates adsorb PAHs so air and subsequently soil and sand will also be contantinated. PAHs generally exhibit strong carcinogenic and mutagenic activity. For example, benzo[a]pyrene (B[a]P) is known as a carcinogenic compound. Synchronously excited fluorescence spectrometry has provided a multicomponent analysis of PAHs (135). After ultrasonic extraction of PAHs, e.g., B[a]P benzo[k]fluoranthene (B[k]F), chrysene (Chry), benzo[a]anthracene (B[a]A), pyrene (Py), perylene (Pery), and benzo[ghi]petylene (B[ghi]pery), from soils, they were separated by TLC on kieselguhr G layers mixed with 26% acetylated cellulose (135). Twelve PAHs... 

In a similar way to pyrene derivatives, the excellent electronic absorption and fluorescence emission properties of perylene derivatives lead to scientists working in various areas of materials science to study their physical properties. Depending... 

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