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41.
42.
Effect of sound pressure level on acoustic impedance of an orifice in a baffle is investigated based on the measurements performed in an impedance tube by the two-microphone method. Dependences of imaginary and real parts of impedance on the orifice diameter are obtained in nonlinear conditions. Special attention is paid to the attached length (the end correction) of the orifice. Dependence of the attached length of an orifice on the oscillating velocity in it is approximated by analytic functions. 相似文献
43.
It is theoretically shown that creation of artificial inhomogeneities allows one to control dynamics of two-dimensional dark quasi-solitons in a Bose-Einstein condensate. A method to calculate trajectories of these quasi-solitons is proposed. It allows control parameters to be selected for the potentials responsible for formation of the Bose gas density distributions required for the scattering through the given angle. 相似文献
44.
A. Thomas N. S. Borisov H. -J. Arends A. N. Fedorov G. M. Gurevich R. L. Kondratiev M. Korolija A. B. Lazarev M. Martinez W. Meyer S. V. Mironov A. B. Neganov V. N. Pavlov H. Ortega G. Reicherz Yu. A. Usov 《Physics of Particles and Nuclei》2013,44(6):964-967
The new frozen spin polarized target for experiments at the polarized beam of the real photon facility A2 of the MAMI accelerator is described. The A2-collaboration at the Mainz Microtron MAMI is measuring photon absorption cross section using circularly and linearly polarized photons up to the energy of 1.5 GeV. The photons are produced in the’ Bremsstrahlungs’ process. In the years 2005/2006 the Crystal Ball detector with its unique capability to cope with multi photon final states was set up in Mainz. Since 2010 the experimental apparatus has been completed by a polarized target. The horizontal dilution refrigerator of the Frozen-Spin Target has been constructed and is operated in close cooperation with the Joint Institute for Nuclear Research in Dubna, Russia. The system offers the opportunity to provide longitudinally and transversely polarized protons and deuteron. In this paper the operation experience of this new Frozen-Spin Target and first results from the runs in 2010 and 2011 are presented. 相似文献
45.
46.
S. V. Bashkin A. O. Karfidov V. N. Kornienko M. V. Lel’kov A. I. Mironov A. N. Morozov S. I. Svetlichnyi S. E. Tabalin I. L. Fufurin 《Optics and Spectroscopy》2016,121(3):449-454
The construction and principle of operation of a imaging Fourier transform infrared spectroradiometer (FTIR spectrometer) equipped with a cooled 32-area photodetector designed for spectral analysis of open atmospheric paths are considered. The main technical characteristics of the Fourier spectrometer are reported. The technique of visualization of the detected vapor cloud is described. The results of field experiments using the imaging FTIR spectrometer are shown. Based on these results, the dynamics of motion of the cloud of material has been investigated, its angular and linear velocities have been estimated, and data on propagation of the cloud of material and change in its angular sizes in air have been obtained. A technique for analyzing data provided by two FTIR spectrometers is given, based on which one can estimate the size of the cloud and the distance to it from each device. It is shown that the results of detection of the cloud of material by the imaging FTIR spectrometer can be used to predict the propagation of material under study in space. 相似文献
47.
Alexey V. Laptev Dmitrii E. Pugachev Alexey Yu. Lukin Andrei V. Nechaev Nikolay E. Belikov Olga V. Demina Petr P. Levin Andrey A. Khodonov Andrey F. Mironov Sergei D. Varfolomeev Vitalii I. Shvets 《Mendeleev Communications》2013,23(4):199-201
A new 5,10,15,20-tetrasubstituted porphyrin containing four 6’-nitro-1,3,3-trimethylspiro(indolino-2,2’-2H-chromene) substituents and its complexes with Zn2+ and Cu2+ ions were prepared and characterized by physicochemical methods of analysis. 相似文献
48.
Burdastyh M. V. Postolova S. V. Derbezov I. A. Gaisler A. V. Diamantini M. C. Trugenberger C. A. Vinokur V. M. Mironov A. Yu. 《JETP Letters》2019,109(12):795-798
JETP Letters - We investigate the evolution of the electronic transport in disordered NbTiN films at the insulating side of the superconductor-insulator transition as function of the effective... 相似文献
49.
Vokhmintcev A. V. Melnikov A. V. Mironov K. V. Burlutskiy V. V. 《Doklady Mathematics》2019,99(1):108-112
Doklady Mathematics - A closed-form solution is proposed for the problem of minimizing a functional consisting of two terms measuring mean-square distances for visually associated characteristic... 相似文献
50.
V. V. Privezentsev M. V. Chukichev R. V. Mironov Yu. V. Krivenkov 《Bulletin of the Russian Academy of Sciences: Physics》2012,76(9):995-998
Changes in the optical properties of a Si layer broken as a result of implantation by Zn ions are investigated during thermal annealing. The investigations are performed by Raman scattering (RS), ellipsometry, and cathodoluminescence (CL). The implanted samples show a broken area with a thickness of about 60 nm with partial amorphization. Thermal treatment at 400°C results in the partial annealing of a radiation point defect while reducing the thickness of the broken layer to 40 nm. The broken layer was completely restored after high-temperature annealing at 700°C. 相似文献