The perspectives of using laser multiphoton dissociation processes for analysis of the polyatomic molecules are considered. It is shown that mass analysis of both the initial molecules and the fragments of dissociation is preferably to be carried out by means of linear ion trap acting in MS regime. New schemes of laser photodissociative spectrometer based on the mode locked NH3-CO2 laser and linear ion trap are proposed for realization of MS regime. Principle parameters of this laser (wavelength region from 9 to 13.5 μm, pulse energy approximately 1 J, pulse duration from 10 ns to 2 μs and pulse repetition from 1 Hz to 1 kHz) allow investigating the large number of the polyatomic molecules. Using of a linear ion trap reduces influencing of a space charge and increases an interaction range of laser radiation with ions as contrasted to three-dimensional trap. Using of non-linear effects of motion of entrapped ions in the linear ion trap will give possibility to interact by laser radiation with ions on an axis Z inside the quadrupole capacitor. This fact essentially increases sensitivity of the analysis. Resonant interaction of laser and radio-frequency fields with ions increases resolution of such method of the analysis too.
Here we consider the plasma-chemical precipitation mechanisms of various oxides of metals from a solid phase on a surface of glass by action of IR laser. There defined threshold values of power density of laser radiation at which a change of plasma-chemical reactions occurring on glass surface takes place. A combined (laser and gas-discharge) method of precipitation of oxides of silicon on a surface of glass from a gas phase is offered.
The conditions of obtaining of synchronous generation on two far separated frequencies in range 9 - 13 μm by means of the NH3 - CO2 laser system are reviewed. It is shown, that the two-frequency generation can be achieved by three main ways: (1) using the features of diffraction gratings operating in an autocollimation of the high orders; (2) using the effect of saturation of active medium of the converter of NH3 - CO2 laser system; (3) using the raster system of optical pumping of the converter. The advantages and lacks of each way are reviewed at remote sensing of atmosphere in range 9 - 13 μm.
The method of differential absorption with scattering (DAS) for atmosphere probing by means of NH3-CO2 laser system on the two wavelengths of infrared region far separated from each other is reviewed. The most perspective scheme of remote probing of atmosphere by such method is determined. The efficiency of NH3-CO2 lidar in region 9 - 13 μm is shown. There was found, that using of passive synchronization of longitudinal modes does not require corrections, taking into account the differences in the generation pulses shape of NH3 and CO2 lasers, if the analysis of a registered signal will be fulfilled on the front of a scattered radiation. The calculations of the probing sensitivity and remoteness on some components of atmosphere polluting, such as CCI4, NH3 and CFCl3 there carried out with lidar equation helping.
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