Hump schemes

TRL Report 186 - Traffic calming - Road hump schemes using 75 mm... 

The synthetic alkaloid coralyne (Scheme 1) on the other hand is a planar molecule and is not readily soluble in aqueous buffers. It is highly soluble in ethanol and methanol. Coralyne is characterized by strong absorption maxima at 219, 300, 311, 326 and 424 nm with characteristic humps at 231, 360 and 405 nm in 30% (v/v) ethanol. It is highly fluorescent and gives an emission spectrum with a maximum at 460 nm when excitation was done either at 310 or 424 nm. It was observed that both absorbance and the fluorescence pattern of coralyne remained unaltered in buffer of various pH values ranging from 1.0 to 13.0 and also with salt concentration ranging from 4.0 to 500 mM. This implied that hydrophobic environment favoured the increment of their fluorescence properties [144]. 

For some spectroscopic problems it is necessary to use three lasers in order to populate molecular or atomic states that cannot be reached by two-step excitation. One example is the investigation of high-lying vibrational levels in excited electronic states, which give information about the interaction potential between excited atoms at large internuclear separations. This potential V R) may exhibit a barrier or hump, and the molecules in levels above the true dissociation energy V(R = 00) may tunnel through the potential barrier. Such a triple resonance scheme is illustrated in Fig. 5.42a for the Na2 molecule. A dye laser Li excites the selected level (v J )... 

The orientation-free scheme of Cho is obtained if 7 = 0.0 and a = 1/6. These figures show a time history of free surface displacements at the location of 150Aa (r = 312, 900 m) far from the center of the initial Gaussian hump. 

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