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Atmospheric lidar techniques for the measurement of wind, temperature, and optical properties of aerosols rely on the exact knowledge of the spectral line shape of the scattered laser light on molecules. We report on spontaneous Rayleigh-Brillouin scattering measurements in the ultraviolet at a scattering angle of 90[degrees] on [N.sub.2] and on dry and moist air. The measured line shapes are compared to the Tenti $6 model, which is shown to describe the scattering line shapes in air at atmospheric pressures with small bur significant deviations. We demonstrate that the line profiles of [N.sub.2] and air under equal pressure and temperature conditions differ significantly, and that this difference can be described by the $6 model. Moreover, we show that even a high water vapor content in air up to a volume fraction of 3.6 vol.% has no influence on the line shape of the scattered light. The results are of relevance for the future spaceborne lidars on ADM-Aeolus (Atmospheric Dynamics Mission) and EarthCARE (Earth Clouds, Aerosols, and Radiation Explorer). OCIS codes: 280.3640, 280.1310, 290.5830, 300.6390.

We report precision measurements of the refractive indices of dry air, [N.sub.2,] [O.sub.2,] Ar, and C[O.sub.2,] performed by using a frequency comb as the light source in a Mach-Zehnder interferometer setup. Improved dispersion formulas for all gases are derived with a sensitivity level of 10-9. These results are valid for a wavelength range from 740 to 860 nm and are in good agreement with measurements from other groups. OCIS codes: 120.3180, 120.3940, 120.4530.

Propagation of a dye laser beam of wavelength 5700 A through nitrogen is considered. Values of transmittance, averaged over intervals of 0.5 [cm.sup.-1], are obtained for absorber thicknesses of 0.1, 1, and 10 atm-cm, using the quasi-random model of molecular band absorption. From these values, intensities of the absorption lines in the first positive system of [N.sub.2] are simulated in the frequency interval of 17,540-17,548 [cm.sup.1]. OCIS codes: 010.1290, 010.1300, 010.1320, 010.3310.

The absolute value of the efficiency of electron injection from an excited coumarin dye (NKX-2311) into a nanocrystalline ZnO film was estimated through transient absorption measurements. The electron injection process can also be quantitatively analyzed by comparing their efficiencies.

Essential mechanistic aspects of NO/H2/O2 reaction at 140 degree C were studied using mass spectroscopy and DRIFTS. Inactive adsorb NO(sub x) species (spectators) were found to accumulate on both Pt and support surfaces.

The properties of nitrogen-doped fluorinated silicon oxide (SiOF) films deposited on silicon is analyzed using hydrosilicofluoric acid and ammonium hydroxide aqua as sources by the temperature-difference-based liquid-phase deposition (TD-LPD) method. It is concluded that nitrogen-doped SiOF films by the TD-LPD method with NH4OH incorporation is suitable for intermetal dielectric application.

Positron annihilation lifetime spectroscopy (PAS) and nitrogen gas adsorption method (BET) is used to study a number of silica supported nickel carbonate systems and to evaluate the pore size distribution in the samples. It was found that ortho-Positronium (o-Ps) represents the pores of smaller size in a sample with wide pore size distribution.

The frequencies of several new platinum nitride species produced by the reaction of laser-ablated platinum with pure nitrogen is calculated with the density functional theory in addition to the complexes observed in earlier thermal atom studies. Results revealed that absorptions are observed for PtxNN, PtNN(super -), Pt(NN)(sub 2)(super -) and Pt(NN)2 in solid argon and neon.

The accuracy of temperature and simultaneous relative [N.sub.2]-[O.sub.2] concentration measurements of accumulated as well as of single-pulse rotational coherent anti-Stokes Raman spectra has been investigated in air in the temperature range from 300 to 2050 K. The experimental spectra were taken in a high-temperature oven at atmospheric pressure for a constant oxygen concentration of 20.9% (air). The evaluation procedure is based on the energy-corrected sudden-power scaling law. The agreement of the thermocouple readings with the mean values of the evaluated coherent anti-Stokes Raman spectroscopy temperatures is higher than 50 K and independent of the temperature. The evaluated oxygen concentration is found to be in the range from 20.0 to 21.7% and is also independent of the temperature.

Density functional theory is used to study the structural, electronic and optical properties of oxygen-defective [Zn.sub.3][N.sub.2]. The results have shown that [Zn.sub.3][N.sub.2] with nitrogen replaced by oxygen is more stable than that with interstitial oxygen and substitutional oxygen for nitrogen in defective [Zn.sub.3][N.sub.2] is responsible for the n-type conduction character.

The mesoporous SBA-15 material affords chemical versatility due to large pores and flexible pendant proton-exchanging -SO3H functionalities. It is shown that all of the organic templating agent can be removed and the sulfur moieties can be fully oxidized to accessible [equivalent to] Si-(CH2)(sub 3)SO3H groups which exchange their protons with ammonium ions and adsorb nitrogen bases as proton-donor Bronsted acids.

The nanocrystalline porous nitrogen doped titanium dioxide (TiO2) thin films were prepared by reactive DC magnetron sputtering. These studies showed that the films were porous and displayed rough surfaces with sharp, protruding nodules having a crystal structure varying from rutile to anatase depending on the nitrogen content.

The modification of self-assembled monolayers (SAMs) of 4-methyl-1, 1-biphenyl-4-thiols (BPT) on (111) gold and silver substrates by a nitrogen-oxygen downstream microwave plasma and the attachment of acrylic acid to the plasma-modified SAMs are studied. Synchrotron-based high-resolution photoelectron spectroscopy is applied for the purpose.

A study of the theoretical calculations on ground and excited electronic states of N2 adsorbed on Pt(100) for the properties of photoinduced electron attachment states is presented. The results show that desorption occurs after deexcitation to the ground state as the N2 electron attachment state does not dissociate and that some of the desorbing N2 is vibrationally excited because of the increased equilibrium bond length in the electron attachment state.

A study of the fluorescence properties of the two perylenediimide dyes, 9-amino-N-(2,6-diisopropylphenyl)perylene-3,4-dicarboximide (API) and its derivative N,N-di-(tert-butoxycarbonyl)-API, by means of single-molecule spectroscopy in polystyrene at room temperature is presented. The results show that even rather small fluorescent dyes, such as API and DAPI embedded in an amorphous solid exhibit a large variety in spectral appearance and dynamics.

A study of the rotational relaxation of N2 in collisions with NE over a similar temperature range (5-60K) in supersonic expansions, which include also the transition to the adiabatic regime for rotational energy transfer, is presented. The results show that the translational equilibrium between two mixture components is maintained over most of the range and hints of separation appear just for the lowest Knudsen number expansions.

A study of (sup 14)N/(sub 15)N equilibrium isotope effect for the electron transfer process between N,N,N',N'-tetramethyl-p-phenylenediamine (TMPD) and its radical cation percholate Wurster's blue is presented. The results show that (sup 15 )N-substitution of TMPD decreases appreciably the ionization potential of the molecule, making it easier to lose electron forming the corresponding radical cation in solution.

The endohedral nitrogen-atom-containing fullerenes, N@C(sub 60) and N@C(sub 70) are studied mass spectrometrically. The results are discussed in light of the thermal instability of nitrogen-atom-containing endohedral compounds compared to noble-gas-containing analogues.

We present the computer-generated images of streamer propagation in an overvolted parallel plate gap at atmospheric pressure. Two-dimensional colored images of cross sections of streamers and electric field are presented. The results show the filamentary nature of the streamers and the strong field distortions caused by the space charge. Index Terms - Breakdown, streamers.