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1.
Diagnostics of a near-surface laser plasma, the plasma of a strong-current pulse gaseous discharge in inert gases, nitrogen,
and carbon dioxide under conditions of intense evaporation of the wall of the discharge chamber, the plasma of a discharge
with a hollow cathode, and the active medium of an excimer laser was conducted by methods of intracavity laser spectroscopy
and laser-induced fluorescence. The dynamic fields and absolute concentrations of atoms, ions, molecules and electrons, the
plasma temperature, and the velocities of flows of particles were measured. The quantitative determination of the density
of particles in the erosion laser flame prior to breakdown and the phenomena associated with the formation of molecules in
the laser plasma received primary consideration.
To whom correspondence should be addressd.
Instite of Molecular and Atomic Physics of the Academy of Sciences of Belarus, 70, F. Skorina Ave., Minsk, 220072, Belarus.
Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 64, No. 3, pp. 281–290, May–June, 1997. 相似文献
2.
The dynamics of near-surface plasma formation and the formation of an erosion plasma flame was investigated for quasi-continuous
laser radiation (λ=1.06 μm, q=0.1–10 MW/cm2, τ∼1.5 msec) acting on bismuth targets in air. The absence of low-threshold plasma formation at q<2 MW/cm2 was established and explained. Instabilities in the plasma formation were revealed and the range of laser radiation power
densities (2≤q≤4 MW/cm2) at which these instabilities take place was determined. At q≥5.4 MW/cm2, brightening of the flame was noted. The dependence of the luminescence temperature of the flame on the laser radiation power
density q was determined.
Institute of Molecular and Atomic Physics, National Academy of Sciences of Belarus, 70, F. Skorina Ave., Minsk, 220072, Belarus.
Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 65, No. 1, pp. 126–133, January–February, 1998. 相似文献
3.
V. S. Burakov A. F. Bokhonov P. A. Naumenkov M. I. Nedel’ko N. V. Tarasenko 《Journal of Applied Spectroscopy》1998,65(3):442-448
From the analysis of the contours of the spectral lines of target-material atoms, the electron and atomic concentrations and
their variation with time are determined in the laser plasma of a combined Cu–Al–Cu target. The time dependences for the concentrations
of electrons and atoms in the ground and excited states are explained within the framework of a model that allows for plasma
decay being determined by processes of three-particle recombination and ionization as well as by the variation in the particle
concentration in plasma expansion.
Institute of Molecular and Atomic Physics, National Academy of Sciences of Belarus, 70, F. Skorina Ave., Minsk, 220072, Belarus.
Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 65, No. 3, pp. 426–432, May–June, 1998. 相似文献
4.
We show the possibility of local spectral determination of nitrogen, oxygen, hydrogen, and carbon in solid materials with
the use of a plasma obtained on exposure of materials to laser radiation, including single laser pulses.
Institute of Molecular and Atomic Physics, National Academy of Sciences of Sciences of Belarus, 70, F. Skorina Ave., Minsk,
220072, Belarus. Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 65, No. 4, pp. 482–485, July–August, 1998. 相似文献
5.
For the first time, the dissipation of laser-radiation energy in the gas surrounding a target is investigated under the conditions
of intense plasma formation near a surface and the existence of large spots of: irradiation. The parameters of different regions
of the heated gas are measured and an energy balance of the process of laser effects is obtained.
Institute of Molecular and Atomic Physics, National Academy of Sciences of Belarus, 70, F. Skorina Ave., Minsk, 220072, Belarus.
Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 65, No. 6, pp. 814–817, November–December, 1998. 相似文献
6.
L. Y. Min'ko A. N. Chumakov A. N. Loparev G. I. Bakanovich V. B. Avramenko 《Journal of Applied Spectroscopy》1998,65(2):273-280
It is established that, in the case of laser action on materials in large illuminated spots in atmospheric-pressure air for
a laser radiation power density q≤2 MW/cm2 (λ=1.315 μm), an evaporative regime with plane scattering of the laser-produced erosion plasma is realized while, for q≈5–17
MW/cm2, the plasma front is transferred to the air, leading to plasma screening of the target and shaping of a subsonic radiation
wave in the air. As the duration of the laser pulses increases (τ∼160 μsec), in spite of the large illuminated spots (S∼150
cm2) the evaporative regime of the laser action with plane plasma scattering goes over into a regime with jet outlow and formation
of a quasistationary shock wave.
Deceased.
Institute of Molecular and Atomic Physics, National Academy of Sciences of Belarus, 70, F. Skorina Ave., Minsk, 220072, Belarus.
Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 65, No. 2, pp. 261–268, March–April, 1998. 相似文献
7.
Using the methods of laser-induced fluorescence and emissive spectroscopy, we carried out investigations of the formation
of TiO molecules in a laser plasma produced by focusing the radiation of an AYG:Nd3+ laser on the surface of a titanium target in air. The radiation flux density varied within the range 108–1010 W/cm2. We investigated the distribution of molecules over internal states and the space-time distributions of Ti atoms in the ground,
metastable, and excited states, as well as of TiO molecules in the ground and excited states. We found that gas-phase reactions
with participation of Ti atoms in the ground state provide the most probable channel for the formation of TiO molecules; the
role of reagents in ionized, excited, and metastable states is of secondary importance.
Institute of Molecular and Atomic Physics, National Academy of Sciences of Belarus, 70, F. Skorina Ave., Minsk, 220072, Belarus.
Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 66, No. 1, pp. 109–115, January–February, 1999. 相似文献
8.
We investigated the effect of the mode composition (longitudinal and transverse modes) of laser radiation on the basic parameters
of the stroke pattern formed on a treated surface placed inside a laser cavity. We found that the contrast of the stroke pattern
formed by a laser beam with a complex set of longitudinal modes depends, in the first place, on the width of the laser radiation
spectrum and the laser cavity length and is virtually independent of the angle of rotation of the beam. In the region of small
rotation angles the broadening of strokes caused by the effect of transverse modes becomes predominant.
B. I. Stepanov Institute of Physics, Academy of Sciences of Belarus, 70, F. Skorina Ave., Minsk, 220072, Belarus. Translated
from Zhurnal Prikaladnoi Spektroskopii, Vol. 64, No. 1, pp. 50–54, January–February, 1997. 相似文献
9.
V. L. Kasyutich 《Journal of Applied Spectroscopy》1998,65(6):936-942
Results of sensitivity measurements in laser refractometric detection in a cylindrical cuvette are reported. A model of laser-beam
transmission in a capillary with a liquid is developed. The influence of the laser-beam position, capillary and liquid characteristics,
and laser power fluctuations on detection sensitivity is discussed.
Institute of Molecular and Atomic Physics of the National Academy of Sciences of Belarus, 70, F. Skorina Ave., Minsk, 220072,
Belarus. Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 65, No. 6, pp. 894–899, November–December, 1998. 相似文献
10.
The authors consider the dependence of hydrogen plasma radiation on the nonideality parameter near the thresholds of spectral
series. At low electron concentrations experimental data agree well with calculations based on the principle of spectroscopic
stability. At higher electron concentrations the experimental data agree better with calculations that include a decrease
in the thresholds of photorecombination in the statistical plasma microfield and a change in the statistical weight of the
levels which is induced by their autoionization in the plasma microfield.
A. V. Luikov Heat and Mass Transfer Institute of the National Academy of Sciences of Belarus, 15, P. Brovka St., Minsk, 220072,
Belarus. Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 65, No. 1, pp. 22–26, January–February, 1998. 相似文献
11.
V. A. Ageev A. F. Bokhonov V. V. Zhukovskii A. A. Yankovskii 《Journal of Applied Spectroscopy》1997,64(5):683-688
We present the results of investigations undertaken to establish relationships between certain characteristics of the disintegration
of metals in air and liquid under laser radiation and their thermophysical properties, as well as between the basic parameters
of a gas cavity formed in a liquid and the energy of the laser ablation products of metals. Consideration is given to the
possibilities of applying the dynamic properties of this cavity to control the time behavior of the radiation of solid-state
lasers and to solve spectroanalytical problems.
Institute of Molecular and Atomic Physics, Academy of Sciences of Belarus, 70, F. Skorina Ave, Minsk, 220072, Belarus. Translated
from Zhurnal Prikladnoi Spektroskopii, Vol. 64, No. 5, pp. 668–673, September–October, 1997. 相似文献
12.
We present the most important results of investigations of lasers based on vapors and solutions of complex organic compounds.
We investigated the effect of a foreign gas, the duration and intensity of the exciting pulse, the temperature of the active
medium, and the spectroscopic parameters of the material on the generation characteristics of complex molecules in the gas
phase. The special features of generation of radiation by a laser with distributed feedback in transition from a condensed
to the gas phase in heating the active medium are considered. It is suggested that the polarization characteristics of the
radiation generated by a vapor laser be used to investigate the laws that govern the relaxation of optically induced anisotropy
of excited molecules of the active medium.
Institute of Molecular and Atomic Physics, National Academy of Sciences of Belarus, 70, F. Skorina Ave., Minsk, 220072, Belarus.
Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 65, No. 5, pp. 709–720, September–October, 1998. 相似文献
13.
A laser system comprising a synchronously pumped picosecond dye laser with combined cavity-distributed feedback and a two-stage
dye amplifier is described. The dependence of the laser pulse duration on the detuning of the cavity length, the pumping level
of the active medium, and the pulse number in the pulse train was investigated. It is shown that the combination of the two
types of feedback provides more than ten-fold shortening of the dye laser ultrashort pulse duration.
B. I. Stepanov Institute of Physics, National Academy of Sciences of Belarus, 70, F. Skorina Ave., Minsk, 220072, Belarus.
Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 65, No. 1, pp. 47–55, January–February, 1998. 相似文献
14.
B. F. Kuntsevich 《Journal of Applied Spectroscopy》1999,66(5):726-732
The nonlinear amplitude-tuning characteristic of a CO2 laser with discharge-current modulation was investigated by mean of numerical simulation. It is shown that in the general
case the magnitude and shape of the laser response depend on the ratio between the frequency of the pump modulation and the
fundamental resonance frequency of the laser.
B. I. Stepanov Institute of Physics, National Academy of Sciences of Belarus, 68, F. Skorina Ave., Minsk, 220072, Belarus.
Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 66, No. 5, pp. 640–644, September–October, 1999. 相似文献
15.
I. V. Osipova I. A. Ryabkov N. G. Vnukova N. V. Bulina G. N. Churilov 《Journal of Applied Spectroscopy》2007,74(1):156-158
We present a design for a dual-jet arc plasmatron operating at a frequency of 66 kHz in an argon flow at atmospheric pressure.
We present the results of determination of the temperature, electron concentration, and electrode erosion obtained by atomic
emission spectral analysis. The proposed convenient design for a dualjet plasmatron and the low erosion of the copper electrodes
in the plasma make it possible to use it for medical purposes.
Report given at the Fifth International Conference on Plasma Physics and Plasma Technologies (PPPT-5), 18–22 September 2006,
Minsk, Belarus.
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Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 74, No. 1, pp. 139–140, January–February, 2007. 相似文献
16.
We present the results of a spectral study of the effect of low-intensity laser radiation on the molecular structure of blood
and blood components. Analysis of the Fourier transform IR absorption spectra of blood confirmed the changes we observed previously
in the oxygen transport characteristics of blood with intravenous exposure to the emission from a He-Ne laser. We show that
structural and conformational changes in the hemoglobin tetramer, initiated by laser-induced photoreactions between Hb and
oxygen, lead to characteristic changes in the shape and intensity of the IR bands for NH stretching vibrations, and also the
amide I and amide II absorption bands. In the IR spectra of irradiated blood samples, we note increased absorption in the
bands for stretching vibrations of the phosphate groups (945–1280 cm−1), which is evidence for an increase in the nucleic acid content (DNA, RNA). In the spectra of plasma and erythrocytes prepared
from irradiated blood, there are no changes in this region of the IR spectrum. At the same time, in the IR spectra of samples
of irradiated plasma, the intensity of the bands for stretching vibrations of the CH2 groups increases substantially.
__________
Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 73, No. 1, pp. 106–112, January–February, 2006. 相似文献
17.
We carried out measurements of the spectral distribution of wideband dye laser generation intensity within the limits and
in the vicinity of an absorption line with its simultaneous recording at the frequencies of the fundamental and second harmonics
of laser radiation. In the laser cavity we placed optical cuvettes with active and absorbing media, as well as selecting and
nonlinear-optical elements. We show that at double frequencies the contrast of the narrow-band hole in the multimode laser
generation spectrum increases. The gain in the concentration sensitivity of measurements depends in this case on the value
of the absorption coefficient being determined.
Institute of Molecular and Atomic Physics, National Academy of Sciences of Belarus, 70, F. Skorina Ave., 220072, Minsk, Belarus.
Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 65, No. 4, pp. 516–521, July–August, 1998. 相似文献
18.
V. B. Gavrilov A. V. Lychkovskii E. P. Shostak S. V. Konev 《Journal of Applied Spectroscopy》1998,65(3):379-384
A more simple and sensitive assay for the quantitative determination of tyrosine in blood plasma is developed on the basis
of a modification of the method of S. Udenfriend (1962). A volume of 0.2 ml of plasma is used in the analysis; after its deproteinization
with trichloroacetic acid, it is reacted with sodium nitride, nitrous acid, and 1-nitroso-2-naphthol at 65°C, and the content
of the reaction product is measured by the fluorescence at λex/λem=460/570 nm. The consumption of plasma and reagents is reduced by a factor of 5–10 compared to the original method; in addition,
the stage of extraction with an organic solvent is excluded. The linear dependence of the fluorescence signal on the tyrosine
concentration within the range of 2–60 μg/ml, high specificity, accuracy, and reproducibility of the assay are shown. The
importance of tyrosine determination in monitoring of glucocorticoid therapy and protein catabolism is discussed.
Institute of Photobiology, National Academy of Sciences of Belarus, 27, Akademicheskaya St., Minsk, 220072, Belarus. Translated
from Zhurnal Prikladnoi Spektroskopii, Vol. 65, No. 3, pp. 366–371, May–June, 1998. 相似文献
19.
O. V. Zhuravleva A. V. Ivanov D. S. Isaev V. D. Kurnosov K. V. Kurnosov V. I. Romantsevich R. V. Chernov 《Journal of Applied Spectroscopy》2005,72(5):757-762
It is shown that superluminescent diodes rank below laser diodes in energy characteristics, but they have a wider emission
spectrum and lower noise level. The amplitude-frequency and noise characteristics of the laser diode correlate with each other,
whereas there is no such correlation for the superluminescent diode. The photon density distribution along the active area
is more homogeneous for the laser diode than for the superluminescent one.
Presented at the 5th International Scientific-Technical Conference “Quantum Electronics,” November 22–25, 2004, Minsk, Belarus.
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Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 72, No. 5, pp. 689–693. September–October, 2005. 相似文献
20.
V. I. Borisov A. M. Kroll V. P. Minkovich N. P. Minkovich 《Journal of Applied Spectroscopy》1999,66(2):278-281
The lasingin an Nd:YAG laser with a fiber-optic reflector in the form of a loop was experimentally investigated. Two designs
of the laser with a fiber-optic loop reflector were considered. In the laser of the first type the reflector was formed by
a fragment of a fiber guide the ends of which were placed in the focal plane of a microscope objective. In the laser of the
second type the role of the output mirror was played by a loop-shaped fiber-optic reflector made on the basis of a V-shaped
fused three-fiber splitter. It is shown that when such lasers operate in the regime of free-running lasing, in them there
takes place the effect of nonlinear conversion of the generated radiation frequency in the Stokes and anti-Stokes regions
of the spectrum.
Institute of Applied Optics, National Academy of Sciences of Belarus, 11, Belynitskii-Birulya Str., Mogilev, 212793, Belarus.
Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 66, No. 2, pp. 259–262, March–April, 1999. 相似文献