Laser studies

On the experimental side, small molecule energy transfer experiments may use molecular beam teclmiques [65. 66 and 67] (see also chapter C3.3 for laser studies). 

Diller R, Malt S, Walker G 0, Cowen B R, Pippenger R, Bogomoini R A and Hochstrasser R M 1995 Femtosecond time-resolved infrared laser study of the J-K transition of bacteriorhodopsin Chem. Rhys. Lett. 241 109-15... 

Flynn G W and Weston R E Jr 1993 Diode laser studies of oollisional energy transfer J. Phys. Chem. 97 8116-27... 

Moore C B 1969 Laser studies of vibrational energy transfer Accounts Chem. Res. 2 103-9... 

Weitz E and Flynn G W 1974 Laser studies of vibrational and rotational relaxation in small moleoules Annu. Rev. Rhys. Chem. 25 275-315... 

Theodore H. Maiman with a ruby that was used in early laser studies in the 196Qs. (Corbis Corporation)... 

Owens, SL, Bunce, C, Brannon, AJ, Xing, W, Chisholm, IH, Gross, M, Guymer, RH, Holz, FG, and Bird, AC, 2006. Prophylactic laser treatment hastens choroidal neovascularization in unilateral age-related maculopathy Final results of the drusen laser study. Am J Ophthalmol 141, 276-281. 

Laser Studies of Radiationless Decay Mechanisms in Os2+/3+ Polypyridine Complexes... 

The importance of chemical laser studies for basic research aimed at more detailed understanding of chemical reactions results from the possible selective population of definite energy levels of the reacting molecules. 

Contents Population Inversion and Molecular Amplification. Energy-partitioning in Elementary Chemical Reactions Vibrational Relaxation. Requirements for Laser Oscillation. Design Parameters of Pulsed Chemical Lasers. Specific Chemical Laser Systems. Future Chemical Lasers. Present Perspectives of High-Power Chemical Lasers. Kinetic Information through Chemical Laser Studies. 

In another picosecond laser study of Forster energy transfer, Sato et al. [165] have studied systems of rhodamine 6G (R6G) and/or 3,3 -diethyl-thiacarbocyanine iodide (DODCI). Satisfactory agreement between the experimentally observed decay of R6G fluorescence and that based on the Forster kinetics [eqn. (85) with a calculated R0 — 5.9 nm and r = 0] was noted. However, from eqn. (85), Uiim 10-9 m2 s-1, so that Forster... 

Gates from the flash and laser irradiation of Pittsburgh seam (hvab) coal were investigated to determine the action of high temperatures on coal. Temperatures in excess of 1000°C. were reached with both types of irradiation. Craters about 300 microns in diameter were produced in the coal with millisecond pulses from the laser unit rated at 1.7 joules output. Gaseous products from the laser and flash irradiations showed 21% and 8% acetylene, respectively. Diacetylene, vinylacetylene, and other products to molecular weight 130 were indicated in the mass spectrum of the gas from the laser study. The results indicated that the distributions of products obtained from the flash and laser irradiations of coal were different from that produced in high temperature carbonization. 

Raman spectroscopy confirms that the dominant form of 3,4-dihydro-2H- pyran at room temperature is the half-chair <74JCP(60)3098) and an angle of twist of 23° is indicated. A pulsed IR laser study of the half-chair to boat interconversion of this dihydropyran has shown that provided at least 20 kJ mol-1 is absorbed a transient UV absorption at 237 nm is observed which is assigned to the boat form (80JA6407). 

H. R. Kim, W. J. Marinelli, and N. Sivakumar, Laser Studies of Molecular Photodissociation Dynamics, to appear in Proceedings Fourth Symposium Recent Advances in Laser Spectroscopy, May 20, 1983, Brooklyn Polytechnic Institute of New York, Wiley, New York. 

Composition and Parameters of an Optimum Gas Genereting Composition for Gas Dynamic Laser Studies... 

Suzuki, T., Kanamori, H., and Hirota, E. (1991). Infrared diode laser study of the 248 nm photodissociation of CH3I, J. Chem. Phys. 94, 6607-6619. 

Synthesis of PP-L-A molecules consisting of bisporphyrin PP linked to a pyromellitimide rather than quinone acceptor A was also reported in [162], For the cofadal bisporphyrin strong quenching of fluorescence was found, while for the side-by-side bisporphyrin relatively weak quenching was observed. Fluorescence quenching data are supported by the direct ps laser studies of PET in PP-L-A molecules with cofacial and side-by-side bisporphyrin. These results show that the proximity of PP and Q is not sufficient for high efficiency of PET. Other factors, such as appropriate geometry of PP play an important role for efficient PET. Note that cofacial bisporphyrin models the special pair electron donor in the reaction centre of photosynthesis. 

Gouedard, G. and Lehmann, J.C. (1981). Pulsed dye-laser studies in the B3E state of Se2 Lande factors and perturbations, Faraday Disc. 

Moser, J. Graetzel, M. Photoelectrochemistry with colloidal semiconductors Laser studies of halide oxidation in colloidal dispersions of Ti02 and a-Fe203, Helv. Chim. Acta 1982, 65, 1436. 

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