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1.
L. P. Runets 《Journal of Applied Spectroscopy》1997,64(6):749-754
A method for determining optical density at the center of an atomic absorption line contour from the spacing between the components
of the two-frequency generation spectrum of a laser with a phase-polarization selector is suggested. It is shown that the
method makes it possible to measure the largest possible optical densities, but it is not suitable for measuring optical densities
smaller than unity. Optical densities at the center of the D-lines of sodium are measured experimentally. A good agreement
between experimental and predicted data is obtained.
Institute 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. 6, pp. 738–743, November–December, 1997. 相似文献
2.
A. P. Zazhogin 《Journal of Applied Spectroscopy》1999,66(3):455-457
On the basis of analysis of relationships relating, among themselves, the positions of bands in the spectra of electron and
IR absorption of uranyl complexes in solutions and the donor ability of neutral ligands, the possibility is shown for fine-tuning
frequencies of absorption of complexes to frequencies of argon- and CO2-laser generation lines and using them in the development of methods of control over chemical reactions involving actinides.
Belarusian State University, 4, F. Skorina Ave., Minsk, 220050, Belarus. Translated from Zhurnal Prikladnoi Spektroskopii,
Vol. 66, No. 3, pp. 420–422, May–June, 1999. 相似文献
3.
V. S. Burakov A. V. Isaevich P. Ya. Misakov S. N. Raikov 《Journal of Applied Spectroscopy》1998,65(1):25-31
Narrow atomic absorption lines of Ba, Cs, Mg, and Tl are recorded in an electrothermal atomizer with a graphite tube furnace
by the intracavity laser spectroscopy method. The conditions of applicability of this laser absorption method for reducing
the observed profiles of spectral lines to the true ones are found. Measurement of the integral absorption coefficient has
made it possible to determine the absolute number of free atoms of each element in the analyte volume at the maximum of the
absorption peak under optimum conditions of atomizer heating. The Voigt parameters are determined from the profiles of absorption
lines.
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. 1, pp. 27–33, January–February, 1998. 相似文献
4.
Using the method of phase-sensitive detection, we investigated the photoconductivity spectra of polycrystalline p-CuInSe2 films obtained in vacuum by the method of pulsed laser vaporization of initial single crystals. We show that, in contrast
to single crystals, films are characterized by monopolar photoconductivity in the extrinsic and intrinsic regions of optical
absorption and by a linear mechanism of recombination of nonequilibrium charge carriers at the intensities of illumination
0–100 mW/cm2 in the temperature range 80–300 K.
Institute of the Solid-State and Semiconductor Physics, National Academy of Sciences of Belarus, 17, P. Brovka St., Minsk
220072, Belarus. Translated from Zhurnal Prikladnoi Spektroskopii. Vol. 66, No. 1, pp. 138–141, January–February, 1999. 相似文献
5.
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
6.
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
7.
B. F. Kuntsevich 《Journal of Applied Spectroscopy》1999,66(2):196-200
The nonlinear amplitude-detuning characteristic of a CO2 laser in loss and refractive-index modulations with frequencies that differ by a factor of two is theoretically investigated.
The response of the laser, in this case, is practically symmetric relative to the center of the line of the working transition
while generation dynamics is complicated due to the appearance of spikes of quadrupling of the oscillation period on the wings
of the line and doubling of the oscillation period in the remaining range of detunings.
B. I. Stepanov Institute of Physics, National Academy of Sciences of Belarus, 68, F. Skorina Ave., Minsk, 220072. Translated
from Zhurnal Prikladnoi Spektroskopii, Vol. 66, No. 2, pp. 185–189, March–April, 1999. 相似文献
8.
B. M. Dzhagarov 《Journal of Applied Spectroscopy》1999,66(4):516-520
Based on the results of studying hemoglobin and myoglobin molecules using the methods of laser absorption spectroscopy of
superhigh time resolution, we described photophysical and spectral properties of excited states, and intramolecular electronic
and thermal relaxation processes. A mechanisms of the photodissociation reaction of oxy forms of these proteins is proposed
and substantiated.
Reported at the VIIIth International Conference on Spectroscopy of Porphyrins and Their Analogs, Minsk, September 22–26, 1998.
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. 4, pp. 479–482, July–August, 1999. 相似文献
9.
We suggest a variant, which has already been implemented, of a selective intracavity laser spectrometer with intracavity nonlinear
optical conversion of the frequency range of generated multimode radiation. The apparatus provides a means for transition
into the UV spectral range (shorter than 300 nm) to carry out direct recording and quantative investigation of strong resonance
lines of atomic absorption, which earlier were beyond the reach of the intracavity method. We measured selective absorption
in spectral lines of a number of metals: FeI 296.690 nm, TiI 294.200 nm, and GaI 287.424 nm.
Institute of Molecular and Atomic Physics, National Academy of Sciences of Belarus, 70 F. Skorina Ave., Minsk, 220072, Belarus;
e-mail: Ild@imaph.bas-net.by. Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 66, No. 6, pp. 875–879, November–December,
1999. 相似文献
10.
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
11.
By taking as an example a He−Ne laser that operates at the 3S2−3P4 transition (λ=3.39 μm), we studied the specific features of nonlinear interaction of the waves of linear orthogonal polarizations
in a transverse magnetic field. Using mutually orthogonal transverse magnetic fields on the neighboring portions of an active
medium, we implemented a regime of two-frequency generation, which was investigated theoretically and experimentally.
To whom correspondence should be addressed.
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. 4, pp. 568–573, July–August, 1999. 相似文献
12.
V. A. Yurevich 《Journal of Applied Spectroscopy》1999,66(5):754-759
Optical-bistability conditions for a thin (smaller than the wavelength of the acting laser radiation) surface layer of resonance
atoms are calculated with allowance for the influence of the polarizing fields of transitions adjacent to the resonance one
and allowed in the electrodipole approximation on the transmissivity of the medium of the layer. It is noted that the change
in the threshold bistability characteristics is due to the influence of the self-modulation broadening of the line of the
laser field occurring in the thin resonancepolarized layer on the effective level of its absorption.
Institute of Applied Optics, National Academy of Sciences of Belarus, 11, Byalynitskii-Birulya Str., Mogilev, 212793, Belarus.
Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 66, No. 5, pp. 661–665, September–October, 1999. 相似文献
13.
This study is carried out to investigate the effect of different plasticizers on characteristics of IR spectra of cellulose
acetates. It is found that processes of intermolecular interaction between macromolecules of the polymer and molecules of
plasticizing materials result in a shift of absorption bands of acetate groups and in changes in attenuation indices for absorption
bands of plasticizers and residual hydroxyl groups in the polymer. The deviation of both the positions of frequencies and
attenuation indices is determined by the type and concentration of the plasticizer and by the content of bound acetic acid
in cellulose acetate films.
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. 869–876, November–December, 1998. 相似文献
14.
A. K. Chaudhary A. M. Rudra P. Kumbhakar G. C. Bhar 《Journal of Applied Spectroscopy》2007,74(4):571-577
We report a technique for the efficient generation of tunable coherent deep UV radiation and its application in studies of
RDX and TNT at the ppm level on the basis of their absorption characteristics. The obtained experimental absorption data are
compared with conventional spectrophotometric data. The UV radiation in the range 200–260 nm has been generated by the type-I
noncollinear third harmonic of the dye laser radiation (600–700 nm) and also by sum frequency mixing (SFM) of Nd:YAG output
(1064 nm) with the second harmonic of the dye laser in β-barium borate (BBO) crystal. The maximum conversion efficiency of
the generated signal is estimated to be 57.5% at λ = 218.9 nm wavelength. Apart from measurements of the absorbance of RDX
and TNT at different concentrations in their respective solutions, the minimum detection concentrations have also been ascertained.
The estimated minimum detectable concentration of RDX is 8.47·10−9 M, whereas that for TNT is 35.7·10−9 M. The data were obtained using only ∼100 μJ/pulse of laser energy.
Published in Zhurnal Prikladnoi Spektroskopii, Vol. 74, No. 6, pp. 516–521, July–August, 2007. 相似文献
15.
Wai-Lun Chan Robert S. Averback D. G. Cahill 《Applied Physics A: Materials Science & Processing》2009,97(2):287-294
We use calorimetry to determine the energy absorption of femtosecond (fs) laser pulses as a function of incident fluence for
Ag, Ag alloys (Ag–Cu and Ag–Pt), and Pt. At low fluences, the measured absorption agrees well with reflectivity data derived
from ellipsometry measurements. For Ag and Ag–Cu, the absorbed energy increases nonlinearly with the incident fluence for
fluences larger than approximately half of the melting threshold. Near this threshold, the absorption increases by a factor
of 3–4. Similar nonlinear absorption is not observed in Pt or Ag–Pt. We propose that the nonlinear absorption is caused by
the excitation of d-band electrons below the Fermi surface. For pulse widths longer than 850 fs, the observed nonlinear absorption
in Ag diminishes, indicating that diffusive transport and not ballistic transport is the major mechanism of cooling at this
excitation level. 相似文献
16.
V. A. Gorobets V. O. Petukhov S. Ya. Tochitskii V. V. Churakov 《Journal of Applied Spectroscopy》1998,65(4):526-534
The possibility of remote detection of SO2 in the 9-μm region of the spectrum by means of a TEA CO2 laser was theoretically and experimentally investigated with regard to the real state of the atmosphere and the contribution
of background concentrations of H2O, CO2 and NH3 to absorption. For sounding along short paths (2L=2 km), the method of detection of small concentrations of SO2 (at the MPC level) with the use of the lines of the CO2-molecule regular transitions (00o1–02o0 band) has been devised and experimentally tested. It is shown that in sounding along longer paths (2L=6 km), a noticeable
increase in sensitivity can be achieved by the generation lines of the CO2-molecule sequential 00o2–02o1 band.
B. I. Stepanov Institute of Physics of the National Academy of Sciences of Belarus, 70, F. Skorina Ave., Minsk, 220072, Belarus.
Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 65, No. 4, pp. 508–515, July–August, 1998. 相似文献
17.
K. N. Korostik 《Journal of Applied Spectroscopy》1998,65(1):55-61
The influence of stimulated emission delay, dynamic shift in generation frequency, residual charge effect, timing jitter of
the radiation and excitation regime of an injection laser, as well as of dispersion in a fiber light guide on the data-internal
storage time in an electrooptical contour is investigated. It is found that the storage duration of an interval depends strongly
on the lifetime of nonequilibrium charge carriers, the simultaneous effect of a residual charge and jitter in an injection
laser, as well as on the dc bias current of the laser.
Belarusian State University, 4. F. Skorina Ave., Minsk, 220050, Belarus. Translated from Zhurnal Prikladnoi Spektroskopii,
Vol. 65, No. 1, pp. 56–61, January–February, 1998. 相似文献
18.
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
19.
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
20.
Absorption and luminescence spectra of a 4-nitro-4-dimethylaminobutadiene molecule in binary solvents have been experimentally
obtained and investigated. Formation of the absorption spectra is associated with a chromophore grouping of the molecule in
a bent state, while the bathochromic shift of the band in the absorption spectrum is consistent with the theory of dipole-dipole
interaction of a bipolar molecule with solvent molecules. The fluorescence spectrum and its form and bathochromic shift depend
not only on the solvent polarity but also on the proportion and kind of binary mixture of solvents. For a certain proportion
of the binary solvent, radiation has been generated at λ=610 nm in pumping by a nitrogen laser.
Reported at the International Conference on Luminescence, November, 22–24, 1994, Moscow.
Belarusian State University, 4, F. Skorina Ave., Minsk, 220080, Belarus. Translated from Zhurnal Prikladnoi Spektroskopii,
Vol. 64, No. 1, pp. 119–121, January–February, 1997. 相似文献