The curves-of-growth of water vapor were measured in the temperature range from 1000 K to 3000 K at a total pressure of 1 atm with a strip burner 6 m long. The fuel was gaseous hydrogen and oxygen. The statistical band model with exponential line intensity distribution was used to reduce the experimental data to yield spectral absorption coefficients (line strength/line spacing) and fine structure parameters (line width/line spacing), averaged over 25-cm(-1) spectral intervals, in the region from 1 micro to 10 micro. Because of the fuels used, the foreign gas broadener was oxygen. An expression is given which permits the calculation of the spectral emission as a function of total pressure, partial pressure of water vapor, and foreign gases and path length. The range of total pressures is limited to the region in which collision broadening is predominant (~0.1 atm to several atm). The results are compared with previous results and with independent laboratory studies. The agreement is excellent.

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Dried oriented purple membrane samples of Halobacterium salinarium were excited by 150 fs laser pulses of 620 nm with a 7 kHz repetition rate. An unusual complex picosecond electric response signal consisting of a positive and a negative peak was detected by a sampling oscilloscope. The ratio of the two peaks was changed by 1) reducing the repetition rate, 2) varying the intensity of the excitation beam, and 3) applying background illumination by light of 647 nm or 511 nm. All of these features can be explained by the simultaneous excitation of the bacteriorhodopsin ground form and the K intermediate. The latter was populated by the (quasi)continuous excitation attributable to its prolonged lifetime in a dehydrated state. Least-square analysis resulted in a 5 ps upper and 2.5 ps lower limit for the time constant of the charge displacement process, corresponding to the forward reaction. That is in good agreement with the formation time of K. The charge separation driven by the reverse phototransition was faster, having a time constant of a 3.5 ps upper limit. The difference in the rates indicates the existence of different routes for the forward and the reverse photoreactions.