194 research outputs found
Determination of the Working Liquids Technical Condition By Analysis of Digital Speckle Images Parameters
The article discusses the practical realization for the optical control method of technical working fluids condition by the analysis of digital speckle images parameters is discussed. The experimental research results on the application of this method for estimation of aviation fuel and motor oil technical condition are presented.
Keywords: motor oil, aviation fuel, speckle, autocorrelation, impurities, diagnostic
Jean Pecquet (1622–1674). To the 400th anniversary of the birth
The article is dedicated to the 400th anniversary of the birth of the outstanding French anatomist, physician and philosopher Jean Pecquet (1622–1674). Pecquet’s biography is connected with the city of Dieppe, where the future scientist was born and got his primary education, and with Paris, where he made his main discoveries in anatomy. Throughout his life, Pecquet collaborated with many prominent scientists of that time (Jacques Mentel, Louis Gayant, Jean Riolan (the Younger)), including not only physicians and anatomists, but also physicists such as Blaise Pascal, Edme Mariotte, Marin Mersenne and Evangelista Torricelli. Pecquet’s most famous discovery is the chyle cictern, or cisterna chyli. The structure was named after of the scientist – “Pecquet’s reservoir (cistern)”. But more revolutionary discovery made by Pecquet is revealing and proving the fact that the lymphatic ducts flow into the superior vena cava indirectly through the venous angles and refuting the conventional opinion on the drainage of lymph into the liver. An important help in Pecquet’s anatomical research and experiments was his passion for the physical and mathematical sciences. In collaboration with Edme Marriott, Pecquet studied the structure of the eyeball and turned out to be more foresighted, because, unlike Marriott, he correctly understood the role of the retina in the functioning of the eye as an organ of vision. Pecquet was one of William Harvey’s supporters regarding his concept of blood circulation. He introduced cutting-edge at that moment technologies into the anatomy methodology, including animal experiments in vivo, and made a fateful contribution to the progress of anatomical science
On the connection between gamma and radio radiation spectra in pulsars
The model of pulsar radio emission is discussed in which a coherent radio
emis-sion is excited in a vacuum gap above polar cap of neutron star. Pulsar X
and gamma radiation are considered as the result of low-frequency radio
emission inverse Comp-ton scattering on ultra relativistic electrons
accelerated in the gap. The influence of the pulsar magnetic field on Compton
scattering is taken into account. The relation of radio and gamma radiation
spectra has been found in the framework of the model.Comment: 15 pages, 3 figures, Russian version accepted to JETP, partly
published in JETP Letters, Vol. 85, #6 (2007
Nuclear Scissors Mode with Pairing
The coupled dynamics of the scissors mode and the isovector giant quadrupole
resonance are studied using a generalized Wigner function moments method taking
into account pair correlations. Equations of motion for angular momentum,
quadrupole moment and other relevant collective variables are derived on the
basis of the time dependent Hartree-Fock-Bogoliubov equations. Analytical
expressions for energy centroids and transitions probabilities are found for
the harmonic oscillator model with the quadrupole-quadrupole residual
interaction and monopole pairing force. Deformation dependences of energies and
values are correctly reproduced. The inclusion of pair correlations
leads to a drastic improvement in the description of qualitative and
quantitative characteristics of the scissors mode.Comment: 36 pages, 5 figures, the results of calculation by another method and
the section concerning currents are adde
Review of scientific topics for Millimetron space observatory
This paper describes outstanding issues in astrophysics and cosmology that
can be solved by astronomical observations in a broad spectral range from far
infrared to millimeter wavelengths. The discussed problems related to the
formation of stars and planets, galaxies and the interstellar medium, studies
of black holes and the development of the cosmological model can be addressed
by the planned space observatory Millimetron (the "Spectr-M" project) equipped
with a cooled 10-m mirror. Millimetron can operate both as a single-dish
telescope and as a part of a space-ground interferometer with very long
baseline.Comment: The translation of the original article in Physics Uspekhi
http://ufn.ru/ru/articles/2014/12/c
Deep BVR Imaging of the Field of the Millisecond Pulsar PSR J0030+0451 with the VLT
We report on deep BVR-imaging of the field of the nearby millisecond pulsar
PSR J0030+0451 obtained with the ESO/VLT/FORS2. We do not detect any optical
counterpart down to B>27.3, V>27.0 and R>27.0 in the immediate vicinity of the
radio pulsar position. The closest detected sources are offset by >3'', and
they are excluded as counterpart candidates by our astrometry. Using our upper
limits in the optical, and including recent XMM-Newton X-ray data we show that
any nonthermal power-law spectral component of neutron star magnetospheric
origin, as suggested by the interpretation of X-ray data, must be suppressed by
at least a factor of ~500 in the optical range. This either rules out the
nonthermal interpretation or suggests a dramatic spectral break in the
0.003-0.1 keV range of the power-law spectrum. Such a situation has never been
observed in the optical/X-ray spectral region of ordinary pulsars, and the
origin of such a break is unclear. An alternative interpretation with a purely
thermal X-ray spectrum is consistent with our optical upper limits. In this
case the X-ray emission is dominated by hot polar caps of the pulsar.Comment: 6 pages, LaTeX aa.cls style, 5 EPS figures. Accepted for publication
in Astronomy and Astrophysic
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