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P. A. Gurevich L. F. Sattarova A. S. Petrovskiy N. A. Frolova B. P. Strunin R. Z. Musin 《Chemistry of Heterocyclic Compounds》2011,46(12):1527-1530
New functionalized condensed benzazoles have been synthesized based on isatin, 3,4-diaminofurazane, and sodium diformylimide. 相似文献
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N. Naumov V. Petrovskiy E. Protsenko V. Yermachenko 《Applied physics. B, Lasers and optics》1997,65(4-5):589-593
4 gas laser with an intracavity absorbing cell is studied experimentally and theoretically at a modulation frequency approximately
equal to the intermode beat frequency. It is revealed that in the vicinity of the absorption-line centre the intensity of
every mode for certain system parameters displays resonance structures narrower than the homogeneous line width of the absorption
line. This occurs when the range of mode synchronization is near the absorption-line centre and its size is less than the
homogeneous width of the absorption line.
Received: 29 February 1996/Revised version: 4 February 1997 相似文献
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V. M. Yermachenko Yu. A. Vdovin V. D. Mironov N. V. Naumov V. N. Petrovskiy N. M. Prokopova V. I. Polsky P. S. Dzhumaev V. L. Yakushin 《Laser Physics》2010,20(6):1537-1544
The effect of the radiation of the pulsed fiber laser on the surfaces of cylindrical samples made of the VT16 titanium alloy is studied. It is demonstrated that the irradiation at appropriate parameters of the laser radiation in the inert-gas (argon) atmosphere leads to an increase in the microhardness of the surface layer and a decrease in the surface roughness of the irradiated samples by a factor of five in comparison with the roughness of the original samples. 相似文献
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R Nirmala V Sankaranarayanan K Sethupathi AV Morozkin T Geethakumary Y Hariharan 《Pramana》2002,58(5-6):1101-1104
New R
2Ti3Ge4 (R=Dy, Ho and Er) intermetallic compounds have been synthesized and characterized by X-ray diffraction and low temperature ac
magnetic susceptibility, electrical resistivity and thermoelectric power measurements were carried out. The compounds crystallize
in the parent, Sm5Ge4-type orthorhombic structure (space group Pnma) and lanthanide contraction is observed as one moves along the rare-earth series.
The changeover from paramagnetic to antiferromagnetic phase happens at low temperatures and the ordering temperature scales
with the de Gennes factor. The electrical resistivity is metallic with a negative curvature above 100 K. Thermopower displays
a weak maximum at temperatures less than 50 K signifying the possible phonon and magnon drag effects. 相似文献
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Yermachenko V. M. Kuznetsov A. P. Petrovskiy V. N. Prokopova N. M. Strel’tsov A. P. Uspenskiy S. A. 《Laser Physics》2011,21(8):1530-1537
The properties of the plasma that results from the laser welding of metals at various powers of the 10-kW ytterbium-doped
fiber laser are experimentally studied. A projection system with an image intensifier based on a copper-vapor laser is employed
for the direct observation of metal surface in the course of the laser welding in the presence of the high-intensity background
illumination. A method for the shadow photographing is proposed for the analysis of the presence of metal vapor in plasma,
since such vapor can lead to the reflection of the laser radiation in the course of welding. 相似文献
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Ishkinyaev E. D. Petrovskiy V. N. Polskiy V. I. Dzhumaev P. S. Sergeev K. L. Shcekin A. S. Panov D. V. Ushakov D. V. 《Physics of Atomic Nuclei》2019,82(11):1441-1444
Physics of Atomic Nuclei - The paper presents the results of mechanical tensile tests and microhardness of samples obtained from stainless steel 316L powder by direct laser deposition. The strength... 相似文献
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S. A. Uspenskiy P. Yu. Shcheglov V. N. Petrovskiy A. V. Gumenyuk M. Rethmeier 《Optics and Spectroscopy》2013,115(1):140-146
We have conducted spectroscopic studies of the welding plasma formed in the process of welding with an ytterbium fiber laser delivering output power of up to 20 kW. The influence of shielding gases (Ar, He) on different parts of the welding plume is investigated. The absorption coefficient of the laser radiation by the welding-plume plasma is estimated. Scattering of 532-nm probe radiation from particles of the condensed metal vapor within the caustic of a high-power fiber laser beam is measured. Based on the obtained results, conclusions are made on the influence of the plasma formation and metal vapor condensation on the radiation of the high-power fiber laser and the stability of the welding process. 相似文献
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Resonant ultrasound spectroscopy was used to measure the elastic constants of bcc Ta0.33V0.67 over the temperature range 3.5–300?K; the results were compared to earlier measurements on C15 TaV2. The temperature dependence of the polycrystalline shear modulus is completely different in the two phases; that of the bcc phase decreases with temperature whereas that of the C15 phases increases in an anomalous fashion. This difference is consistent with a model involving doubly-degenerate levels at the X point of the Brillouin zone in the C15 phase with the Fermi level lying near the doubly degenerate level. This model accounted for the unusual behaviour of the C15 phase. Debye temperatures were determined from the ultrasonic measurements: 295?K for the C15 phase and 315?K for the bcc phase. 相似文献
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