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301.
M. V. Belyayev V. P. Chebotayev M. N. Skvortsov L. S. Vasilenko 《Applied physics. B, Lasers and optics》1981,26(1):67-72
Polarization decay in the presence of a standing electromagnetic wave field at a Doppler broadened transition is investigated theoretically and experimentally. It is shown that in the direction opposite to the propagation of an excited pulse the polarization decays at a transition frequency rather than at an exciting field frequency as usual. This permits the use of transients both in studies of relaxation processes and in Doppler-free super-high resolution spectroscopy. A resonant coherent transient has been used in measurements of relaxation decay constants of a dipole moment for collisions in SF6 (=10.6m). This method has enabled one to resolve reliably the structure of theQ(38) transition (=10.6m) of theF
1
0
+E
0=F
2
0
line of the 0v
3 band in SF6 within a Doppler absorption line. 相似文献
302.
A. N. Goncharov M. N. Skvortsov V. P. Chebotayev 《Applied physics. B, Lasers and optics》1990,51(2):108-115
The paper describes detailed experimental studies of the width, shape and shifts of saturated absorption resonances at the X(v=0, j=13)B(v=43, j=12) transition of molecular iodine. Use of the geometry of oppositely travelling and unidirectional waves in the experiment and study of the luminescence decay under pulsed excitation allowed estimation of the cross-sections of elastic and inelastic scattering of I2 molecules on the upper and lower levels of transition. The observed nonlinear dependence of width and shift of the saturation resonance on iodine pressure is explained by the influence of elastic collisions with no phase mismatch. 相似文献
303.
304.
A. I. Lytkin V. V. Chernikov O. N. Krutova V. E. Litvinenko A. V. Volkov S. A. Bychkova I. A. Skvortsov 《Russian Journal of Physical Chemistry A, Focus on Chemistry》2018,92(1):70-74
Enthalpies of dissolution are found for crystalline racemic tartaric and glutaric acids and isatin in water and in potassium hydroxide solutions at 298.15 K via direct calorimetry. The protolytic equilibria in isatin aqueous solutions are studied at 298.15 K and ionic strengths of 0.5 (relative to potassium nitrate) by potentiometric means. Standard enthalpies of formation are calculated for racemic tartaric and glutaric acids, isatin, and the products of their dissociation in aqueous solutions. 相似文献
305.
A. A. Ponomarev E. A. Zadumina I. A. Markushina I. M. Skvortsov 《Chemistry of Heterocyclic Compounds》1971,4(4):442-443
By reductive amination, starting from furfural, 5-methylfurfural, -(2-furyl)acrolein, and monoethanolamine, we have obtained N-furfurylaminoethanol, N-(5-methyl-2-furfuryl)aminoethanol, and N-[1-(-furyl)-3-propyl]aminoethanol. By reductive amination combined with the subsequent hydrogenation of the furan ring we have obtained N-tetrahydrofurfurylaminoethanol and N-(5-methyltetrahydro-2-furfuryl)aminoethanol.For part XXXIII, see [1]. 相似文献
306.
A. N. Goncharov A. Yu. Nevsky M. N. Skvortsov 《Applied physics. B, Lasers and optics》1996,62(4):427-430
Saturated absorption spectroscopy was applied to study the line shape of the molecular iodineX( = 0,J = 13,15) B( = 43,J = 12, 16) transition ( = 514.5 nm) in a transversal magnetic field as high as 0.51 T. The Zeeman structure of several hyperfine structure (hfs) components was completely resolved and a detailed study of the second-order Zeeman shift and splitting was made. The anisotropic Magnetic Susceptibility (MS) of the molecular iodine both in theB(43) (X = 7.3 ± 1 × 10–34 J/Oe2) and theX(0) [ = (0.6 ± 1) × 10–34 J/Oe2] states as well as the isotropic MS difference [0 –o = (2 ± 0.2) × 10–34 J/Oe2] was measured. 相似文献
307.
The main physical characteristics of monofunctionals in adsorption chromatography - the adsorption interaction parameter of the repeat units c and the interaction parameter of specific end group q - are discussed. Both parameters are independent on column dimensions and pore diameter, and depend on mobile phase composition. In a plot of elution volumes V(n) vs. the difference DeltaV=V(n)-V(n-1) in elution volumes of consecutive non-functional or monofunctional oligomers, straight lines with the same slope are obtained for sufficiently high molar masses. The intercept of these lines yield the accessible volumes of functionalized and non-functionalized oligomers. In the range of weak interaction, the interaction parameter of the repeat unit can be determined using monofunctional chains with strongly adsorbing end group. Scope and limitations of this approach are studied using monoalkyl ethers of polypropylene glycol as model polymers. 相似文献
308.
In a nonlinear formation, the plane steady filtration of a liquid in the case of variable initial gradient is investigated. Accurate analytical solutions of a number of problems are obtained for certain dependences of the initial gradient on the coordinate of a point in the region.Translated from Izvestiya Akademii Nauk SSSR, Mekhanika Zhidkosti i Gaza, No. 2, pp. 46–53, March–April, 1977.The authors thank R. S. Khamitov for assistance with the calculations. 相似文献
309.
L. S. Skvortsov 《Fluid Dynamics》1975,10(1):160-162
The article discusses the settling of heavy solid particles in the conical interplate gap of a centrifugal separator. The residual concentration at the outlet from the interplate gas is calculated using the equation of the conservation of mass for the solid component. Formulas are obtained for calculating the residual concentration for the cases of the settling of monodisperse and polydisperse fractions of the solid component, with a known initial distribution of the concentration. 相似文献
310.
M. Yu. Bogolyubsky A. Yu. Bordanovsky A. A. Volkov D. K. Elumahov V. P. Efremov A. A. Ivanilov A. Yu. Kalinin A. N. Krinitsyn V. I. Kryshkin N. V. Kulagin D. I. Patalakha V. V. Skvortsov V. V. Talov L. K. Turchanovich 《Physics of Atomic Nuclei》2017,80(3):455-460
Relative yields of high-x F charged hadrons (π ±, К±, р, \(\overline p \), and d) in proton–nucleus interactions at incident-proton momenta of 25 and 50 GeV/c were measured at an angle of 0° in the momentum range between 15 and 40 GeV/c. An upper limit on the forward production of two protons in proton–nucleus interactions at 50 GeV/c was estimated. The properties of a carbon beam with an energy of 25 GeV per nucleon and fragment yields in its interaction with nuclear targets were measured within a short exposure. 相似文献