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A. E. Akmalov A. S. Bogdanov G. E. Kotkovskii E. M. Spitsyn A. V. Sychev A. N. Perederii A. A. Chistyakov 《Instruments and Experimental Techniques》2013,56(3):309-316
A compact instrument that implements for the first time a method for analyzing substances, in which laser desorption of analyzed molecules and laser ionization of an air sample are combined with the ionmobility increment spectroscopy, is described. Pulse radiation of the fourth harmonic of a portable (2.6 kg) GSGG: Cr3+: Nd3+ laser (λ = 266 nm) is used. The detection limit of the developed laser desorption spectrometer of the ion-mobility increment is 40 pg for trinitrotoluene (TNT), and the linear dynamic range for TNT is 0.1–20.0 ng. The results from detection of nitro compounds are presented: trinitrotoluene, cyclotrimethylene trinitramine (RDX), and octogen (HMX). It is shown that laser desorption of nitro compounds from a metal is accompanied by their decomposition on the surface and emission of fragments. An ion signal is obtained for nitro compounds that were ionized outside the spectrometer. 相似文献
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G. E. Kotkovskii I. L. Martynov V. V. Novikova A. A. Chistyakov 《Instruments and Experimental Techniques》2009,52(2):253-259
The process of ion-packet broadening in a longitudinal laser spectrometer of ion mobility is studied. The contributions of
the diffusion, Coulomb, and other broadening mechanisms are compared. The resolution of the developed spectrometer was measured
(R ∼ 45) in atmospheres of both purified air and pure nitrogen. The dependence of the spectrometer resolution on the drift voltage
was studied. The recorded spectra of a number of molecules of explosives with an extremely low pressure of saturated vapors
indicate a high sensitivity of the developed spectrometer (no worse than 10−14 g/cm3).
Original Russian Text ? G.E. Kotkovskii, I.L. Martynov, V.V. Novikova, A.A. Chistyakov, 2009, published in Pribory i Tekhnika
Eksperimenta, 2009, No. 2, pp. 110–116. 相似文献
3.
I. L. Martynov V. A. Karavanskii G. E. Kotkovskii Yu. A. Kuzishchin A. S. Tsybin A. A. Chistyakov 《Technical Physics Letters》2011,37(1):15-18
A new ion source for ion mobility spectrometry based on UV laser action upon the surface of porous silicon, is described for
the first time. It is found that the yield of TNT negative ions from this source is higher by an order of magnitude than in
the case of multistep laser ionization of TNT-containing air mixture. It is established that factors important for the formation
of negative ions in the case of continuous supply of analyt to the ionization region are (i) electron emission from the irradiated
surface and (ii) subsequent ionmolecular reactions in the gas phase. 相似文献
4.
A new method is proposed and implemented, according to which small concentrations of organic compounds in the atmosphere are
measured by combining the ion mobility increment spectrometer and laser ionization. The experimental setup makes use of the
pulsed fourth-harmonic radiation of a YAG:Nd3+ laser (λ = 266 nm). At high intensities (q ∼ 107 W/cm2) of laser radiation, ion spectra with reactant peaks are observed, which are identical to the spectra obtained with traditional
sources of ionization by corona discharge and β radiation. The ion spectra obtained at low laser radiation intensities (q ∼ 105 W/cm2) are free of background and reactant peaks, which ensures the high selectivity of the analysis. It is concluded that the
mechanism of negative ion formation from the molecules of nitro compounds can change depending on the intensity of ionizing
laser radiation. 相似文献
5.
G. E. Kotkovskii A. V. Sychev A. V. Tugaenko A. A. Chistyakov 《Instruments and Experimental Techniques》2011,54(2):256-261
A method for analyzing a substance has been experimentally tested. The method combines the field-asymmetric ion mobility spectrometry
and laser ionization of molecules under atmospheric pressure. Pulsed radiation of the fourth harmonic of an YAG: Nd3+ laser (λ = 266 nm) and a spectrometer with a cylindrical analysis camera were used. The results of detecting nitrocompounds—trinitrotoluene,
cyclotrimethylenetrinitramine (hexogen, RDX), etc.—are presented. The experimental detection limits of the spectrometer are
5 × 10−15 g/cm3 (cyclotrimethylenetrinitramine) and ≤3 × 10−15 g/cm3 (trinitrotoluene). 相似文献
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