Random lasing

Quochi, F., Cordelia, F., Mura, A., Bongiovanni, G., Balzer, F. and Rubahn, H.-G. (2005) One dimensional random lasing in a single organic nanofiber. The Journal of Physical Chemistry. B, 109, 21690-3. 

M. Anni, S. Lattante. R. Cingolani, G. Gigli, G. Barbarella and L. Favaretto, Far-field emission and feedback origin of random lasing in ohgothiophene dioxide neat film, Appl. Phys. Lett., 83, 2754-2756 (2003). 

X. Jiang and C. M. Soukoulis, Localized random lasing modes and a path for observing localization, Phys. Rev. E, 65, 025601-4 (2002). 

This is a new effect, where conventional directional lasing is enhanced by weak scattering in particles of nanometer size that is, under some given conditions scattering is shown not to be detrimental to conventional laser emission but, on the contrary, it enhances that emission. It should be remarked that this is not random lasing, were the presence of scatterers in gain media results in omnidirectional laser emission with no spatial coherence but conventional directional laser emission enhanced via NRFL in weakly scattering particles. 

Two-photon pumped random lasing in a dye-doped silica gel powder. Proc. SPIE, 7598, 759804-1-7. 

Garcfa-Revilla, S., Sola, I., Baida, R., Roso, L., Levy, D., Zayat, M., and Fernandez, J. (2010) Two-photon pumped random lasing in a dye-doped silica gel powder. 

Shackleton CH, Irias J, McDonald C, Imperato-McGinley J (1986) Late-onset 21-hydroxy-lase deficiency reliable diagnosis by steroid analysis of random urine collections. Steroids 48 239-250... 

Two types of restriction-modification system have been found in bacteria. In type I systems, the methy-lase and R. e. are both associated with a complex containing three different polypeptide chains an a-chain with R.e activity, a P-chain with methylase activity and a y-chain with the recognition site for the DNA sequence. Type I systems require S-adenosyl-t-me-thionine and ATP for both R.e. and methylase activities they are less specific, and cleavage sites may be random and far removed (1,000 base pairs) from the 5 side of the recognition site. In type II systems, me-thylases and R.e. are separate, 5-adenosyl-L-methio-... 

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