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171.
The problem of a direct-axis collision of a body affinite mass and a semi-infinite cylindrical shell with fluid is considered, and is solved using an analytic-numerical method, which is based on an application of the Laplace-Carson transform with its subsequent numerical inverse. An expression is found for the interaction force for the body and the hydro-elastic system, which allows us to determine the time of collision. Numerical results of calculations of the interaction force and the time of collision are given.Translated from Dinamicheskie Sistemy, No. 7, pp. 29–32, 1988. 相似文献
172.
173.
P. N. Aruev Yu. M. Kolokolnikov N. V. Kovalenko A. A. Legkodymov V. V. Lyakh A. D. Nikolenko V. F. Pindyurin V. L. Sukhanov V. V. Zabrodsky 《Journal of Surface Investigation: X-ray, Synchrotron and Neutron Techniques》2010,4(1):99-103
A photodiode developed at the Ioffe Physico-Tech nical Institute (St. Petersburg) and referred to in the literature as the
SPD has been preliminarily calibrated by the primary-detector-based method. The possibility of application of SPD photodiodes
as radiometric detectors has been investigated. The AXUV-100 photodiode (IRD Inc., United States) was used as a primary detector.
The radiation strength of both detectors has been tested. It was revealed that, being more radiation-resistant, the SPD had
radiometry characteristics that were not worse than those of the AXUIV-100. 相似文献
174.
Diffusion and solubility of helium in Ce0.8Gd0.2O1.9 − δ ceramics (δ = 0, 0.015) with a submicrocrystal structure are studied by thermodesorption of helium from preliminarily saturated
(in the gas phase) crystals at temperatures of 613 and 673 K in the saturated pressure range 0–21 MPa. It is shown that, in
this ceramics (δ = 0), the defect-trap diffusion mechanism operates. The main positions for dissolution are neutral anion
vacancies formed as a result of thermal dissociation of impurity-vacancy complexes and saturated up to ∼1 × 1019 cm−3 at P = 6 MPa and T = 673 K. The dissociation energy of the complex and the energy of helium dissolution in the neutral anion vacancy are estimated
at ∼2 eV and below −0.3 eV, respectively. 相似文献
175.
N. N. Agapov A. V. Alfeev V. A. Andreev V. I. Batin O. I. Brovko A. V. Butenko B. -R. V. Vasilishin V. I. Volkov A. I. Govorov E. D. Donets E. E. Donets D. E. Donets A. V. Eliseev I. B. Issinskii V. N. Karpinskii V. D. Kekelidze A. D. Kovalenko O. S. Kozlov I. N. Meshkov V. A. Mikhailov V. A. Monchinskii P. A. Rukoyatkin N. V. Semin A. O. Sidorin A. N. Sissakian V. M. Slepnev A. S. Sorin G. V. Trubnikov G. G. Khodzhibagiyan 《Physics of Particles and Nuclei Letters》2010,7(7):442-445
The Nuclotron superconducting synchrotron was constructed in 1987–1992 [1]; it is the world’s first synchrotron based on fast cycling “window frame” electromagnets with a superconducting coil. For a design field of dipole magnets of 2 T, the magnetic rigidity is 45 T m, which corresponds to the energy of heavy nuclei (for example, gold) of 4.5 GeV/nucleon. The Nuclotron accelerator complex is currently being upgraded (the Nuclotron-M project); this upgrade is considered a key part of the first stage of fulfilling the new Joint Institute for Nuclear Research (JINR) project: the Nuclotron-based Ion Collider fAcility and Multi-Purpose Detector (NICA/MPD). The most important task of this new project is the preparation of basic Nuclotron systems for its reliable operation as part of the NICA accelerator complex. Basic results of activity on the project, which started in 2007, are presented and the results of the last Nuclotron runs are analyzed. 相似文献
176.
V. N. Karpinskii N. G. Kondrat’ev A. L. Osipenkov V. G. Karavaev N. A. Filippov G. V. Trubnikov A. D. Kovalenko A. O. Sidorin A. V. Butenko V. I. Volkov B. V. Vasilishin A. E. Kirichenko S. V. Romanov 《Physics of Particles and Nuclei Letters》2010,7(7):517-521
One of the trends of Nuclotron development lies in modifying the power supply system and upgrading the energy evacuation system of structural magnets in order to provide reliable durable operation of the synchrotron at a dipole magnet field level of 2 T. This is necessary for Nuclotron operation as part of the injection chain of the heavy-ion NICA collider under design at JINR and for the current program of physical studies. The principles of construction and specific features of the existing system based on a separate power supply of structural dipole and quadrupole magnetic elements are considered. The main provisions of the upgrade of the power supply system, structural and schematic diagrams, control schemes, and energy evacuation switch schemes from superconducting elements are presented. 相似文献
177.
178.
Irina I. Koptyug Anna A. Lysova Galina A. Kovalenko Larisa V. Perminova Igor V. Koptyug 《Applied magnetic resonance》2010,37(1-4):483-495
Heterogeneously catalyzed enzymatic glucose isomerization was considered as a model process to extend the application of nuclear magnetic resonance (NMR) and magnetic resonance imaging techniques to the studies of biocatalytic processes and heterogeneous biocatalysts. It has been demonstrated that the T 2 times of glucose are different for its aqueous solution in the pores of an unmodified porous support and in a heterogeneous biocatalyst, comprising bacterial cells immobilized on the same support. This observation has been used to map the spatial distribution of the active component within a packed bed of biocatalyst in a model reactor. 13C NMR spectroscopy was applied to follow the progress of glucose isomerization catalyzed by the heterogeneous biocatalyst in a batch reactor. The utilization of proton spin decoupling and nuclear Overhauser effect was shown to be necessary to obtain high signal-to-noise ratio in the natural abundance 13C NMR spectra of a glucose–fructose syrup present in the packed bed of biocatalyst. The spectra thus obtained were suitable for the quantification of the glucose-to-fructose ratio achieved in the biocatalytic reaction. 相似文献
179.
S. S. Kovalenko K. A. Petržak K. Irmer G. Musiol 《Isotopes in environmental and health studies》2013,49(10):344-346
The TCAPM was developed to absolute and precise fission cross section measurement for neutron energies from 2 MeV up to 19 MeV. Experimental results of absolute fission cross section measurements on 233U, 235U, 238U, -237Np, 239Pu and 212Pu are given. Furthermore the TCAPM is suitable for the application of inelastic scattering of neutrons by the analysis of element contents. 相似文献
180.
I. B. Krynetskii V. A. Kulbachinskii N. P. Shabanova A. V. Tsikunov R. I. Kovalenko V. V. Rodin S. Yu. Gavrilkin 《Journal of Experimental and Theoretical Physics》2013,116(5):872-875
The temperature dependence of the linear thermal expansion coefficient (TEC) of an InSe single crystal in the (001) plane is measured in the temperature range 7–50 K. A peak in the thermal expansion is detected near T = 10 K, after which the sample shrinks upon heating. The effect of an external magnetic field of up to 6 T, which is parallel to the (001) plane, on the TEC is investigated. The observed partial suppression of the peak and crystal compression by the field indicates the relation of these anomalies to possible electron ordering in InSe layers. 相似文献