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We report water-vapor absorption line measurements that are made by using the first Stokes radiation (930-982 nm) with HWHM 0.015 cm(-1) generated by a narrow-linewidth, tunable dye laser. Forty-five absorption line strengths are measured with an uncertainty of 6% and among them are fourteen strong lines that are compared with previous measurements for the assessment of spectral purity of the light source. Thirty air-broadened linewidths are measured with 8% uncertainty at ambient atmospheric pressure with an average of 0.101 cm(-1). The lines are selected for the purpose of temperature-sensitive or temperature-insensitive lidar measurements. Results for these line strengths and linewidths are corrected for broadband radiation and finite laser linewidth (0.015 cm(-1) HWHM) broadening effects and compared with the high-resolution transmission molecular absorption.

Analyses of spectrophotometric measurements of shrinkage and swelling of liposomes under osmotic-diffusional stress tacitly assume an 'empirical' inverse relationship between the absorbance (A) and the liposomal volume (v). In this paper, we have proposed an alternate more explicit relationship: A = EcL e - alpha Lv/1-Lv where L is liposomal concentration, Ec the extinction coefficient and alpha a dimensionless parameter. The exponential term, in essence, defines the partitioning of aqueous volume into intra- and extra-liposomal compartments. Experimental data obtained with glycerol as model compound are used to test the validity and internal consistency of the proposed formalism.

We report experimental results of multiple Stokes generation of a frequency-doubled Nd:YAG laser in H(2), D(2), and CH(4) in a focusing geometry. The energies at four Stokes orders were measured as functions of pump energy and gas pressure. The characteristics of the Stokes radiation generated in these gases are compared for optical production of multiple wavelengths. The competition between Raman components is analyzed in terms of cascade Raman scattering and four-wave mixing. The results indicate the possibility of using these generation processes for atmospheric aerosol measurements by means of multiwavelength lidar systems. Also this study distinguishes between the gases, as regards the tendency to produce several wavelengths (H(2), D(2)) versus the preference to produce mainly first Stokes radiation (CH(4)).

We describe an efficient Raman shifted dye laser system that generates tunable radiation at 765 and 940 nm with a bandwidth of 0.03 cm(-1). Operating a Raman cell at hydrogen pressure below 14 atm, we recorded optimum first Stokes energy conversions of 45% and of 37% at 765 and 940 nm, respectively. Optical depth measurements made at the centers of twenty-five absorption lines in the P branch of the oxygen A band imply a high spectral purity for both the laser and the Raman shifted radiation, and thus indicate the feasibility of using the stimulated Raman scattered radiation for differential absorption lidar (DIAL) measurements.