661 research outputs found
Kinematics of a Two Movable Disintegrator with Drives Based on the Bennett’s Mechanism
Important factor in the crushing and activation of building materials is the linear velocity of the working organs of the disintegrator. This paper consider the nature of the change of this parameter, as well as the linear velocity of the working element characteristic points. Their values are determined by three independent methods: analytical calculation, CAD / CAE analysis and experimental measurements. The results are compared and analyzed
Long sandwich modules for photon veto detectors
Long lead-scintillator sandwich modules developed for the BNL experiment
KOPIO are described. The individual 4 m long module consists of 15 layers of 7
mm thick extruded scintillator and 15 layers of 1 mm lead absorber. Readout is
implemented via WLS fibers glued into grooves in a scintillator with 7 mm
spacing and viewed from both ends by the phototubes. Time resolution of 300 ps
for cosmic MIPs was obtained. Light output stability monitored for 2 years
shows no degradation beyond the measurement errors. A 4 m long C-bent sandwich
module was also manufactured and tested.Comment: 14 pages, 13 figures, 1 tabl
Casimir effect in a wormhole spacetime
We consider the Casimir effect for quantized massive scalar field with
non-conformal coupling in a spacetime of wormhole whose throat is rounded
by a spherical shell. In the framework of zeta-regularization approach we
calculate a zero point energy of scalar field. We found that depending on
values of coupling , a mass of field , and/or the throat's radius
the Casimir force may be both attractive and repulsive, and even equals to
zero.Comment: 2 figures, 10 pages, added 2 reference
Self-force of a point charge in the space-time of a symmetric wormhole
We consider the self-energy and the self-force for an electrically charged
particle at rest in the wormhole space-time. We develop general approach and
apply it to two specific profiles of the wormhole throat with singular and with
smooth curvature. The self-force for these two profiles is found in manifest
form; it is an attractive force. We also find an expression for the self-force
in the case of arbitrary symmetric throat profile. Far from the throat the
self-force is always attractive.Comment: 18 pages, 3 figures Comments: corrected pdf, enlarged pape
Tempestuous life beyond R500: X-ray view on the Coma cluster with SRG/eROSITA. II. Shock & Relic
This is the second paper in a series of studies of the Coma cluster using the
SRG/eROSITA X-ray data obtained during the calibration and performance
verification phase of the mission. Here, we focus on the region adjacent to the
radio source 1253+275 (radio relic, RR, hereafter). We show that the X-ray
surface brightness exhibits its steepest gradient at (), which is almost co-spatial to the outer edge
of the RR. As in the case of several other relics, the Mach number of the shock
derived from the X-ray surface brightness profile () appears to
be lower than needed to explain the slope of the integrated radio spectrum in
the diffusive shock acceleration (DSA) model () if the magnetic
field is uniform and the radiative losses are fast. However, the shock geometry
is plausibly much more complicated than a spherical wedge centered on the
cluster, given the non-trivial correlation between radio, X-ray, and SZ images.
While the complicated shock geometry alone might cause a negative bias in
, we speculate on a few other possibilities that may affect the
- relation, including the shock substructure that might be modified
by the presence of non-thermal filaments stretching across the shock and the
propagation of relativistic electrons along the non-thermal filaments with a
strong magnetic field. We also discuss the "history" of the radio galaxy
NGC4789, which is located ahead of the relic in the context of the Coma-NGC4839
merger scenario.Comment: Replaced with the accepted versio
Contribution of the Missionary Historic and Ethnographical Museum of the Kazan Spiritual Academy
The urgency of the problem under study is conditioned by the increased interest of contemporary researchers in the problems of interethnic and interconfessional interaction. In the second half of the XIXth - early XXth centuries a major religious and educational, missionary and ethnic-political institution in Russia, the Kazan Theological Academy was one of the leading centers for studying the history, culture, ethnography and the languages of Turkic, Finno-Ugric and Mongolian peoples.
The purpose of the study is to present objectively the contribution of the Missionary Historical Ethnographic Museum of the Kazan Theological Academy to the study and the preservation of the historical and cultural heritage of the Russian state peoples. The museum extensive collections became the basis for modern museums. During the study, the experience of the creation and the functioning of the only missionary historical and ethnographic museum in Russia was analyzed, its contribution to the preservation of spiritual and material culture, written and printed sources, the informative base about the life and work of the multinational and multi-confessional people of the Volga, Urals, Siberia and the Far East was determined.
Based on archival materials, the authors revealed the features of the museum activity at the Kazan Theological Academy. In the course of the topic research, the authors succeeded to identify and collect a huge amount of diverse materials (historical, linguistic, ethnographic ones) about the peoples of Russia, which are of great practical importance for the study of modern interethnic and interfaith relations origins in the Republic of Tatarstan and Russian Federation.
The materials of the article can be useful to anyone who is interested in missionary politics and modern ethnic-political processes in Russian Federation.peer-reviewe
Structure and properties of DOTA-chelated radiopharmaceuticals within the 225Ac decay pathway
The successful delivery of toxic cargo directly to tumor cells is of primary importance in targeted (α) particle therapy. Complexes of radioactive atoms with the 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid (DOTA) chelating agent are considered as effective materials for such delivery processes. The DOTA chelator displays high affinity to radioactive metal isotopes and retains this capability after conjugation to tumor targeting moieties. Although the α-decay chains are well defined for many isotopes, the stability of chelations during the decay process and the impact of released energy on their structures remain unknown. The radioactive isotope 225Ac is an α-particle emitter that can be easily chelated by DOTA. However, 225Ac has a complex decay chain with four α-particle emissions during decay of each radionuclide. To advance our fundamental understanding of the consequences of α-decay on the stability of tumor-targeted 225Ac–DOTA conjugate radiopharmaceuticals, we performed first principles calculations of the structure, stability, and electronic properties of the DOTA chelator to the 225Ac radioactive isotope, and the initial daughters in the decay chain, 225Ac, 221Fr, 217At and 213Bi. Our calculations show that the atomic positions, binding energies, and electron localization functions are affected by the interplay between spin–orbit coupling, weak dispersive interactions, and environmental factors. Future empirical measurements may be guided and interpreted in light of these results
The phenomenon of historical and confessional study of the peoples in the middle volga region, the urals and Siberia in Kazan theological academy (the second half of the xix - The beginning of the XX centuries)
© Serials Publications.The topical character of the theme under investigation is determined by aspiration of the local and foreign researchers for studying problems having great importance for the investigation of the origin of modern international and inter-confessional relations in the Republic of Tatarstan, Russian Federation and Europe as a whole. The object of the paper is to investigate a unique phenomenon of historical and confessional study of the peoples in the Middle Volga region, the Urals and Siberia in Kazan Theological Academy in the second half of the XIX-The beginning of the XX centuries. A leading approach of this research is to present the teachers-missionaries as scientists who had contributed much to the study of history, culture, ethnography and the language of the Turkic, Finno-Ugric, Mongolian peoples. The authors managed to reveal the scientific and educational activities of the missionary department of Kazan Theological Academy, the only one of its kind in Russia, to find out the contribution of its teachers to the study of the peoples in the Middle Volga region, the Urals and Siberia, to find out in the archives different documents (historical, linguistic, ethnographic) concerning the Tatars, the Mari, the Chuvash, the Bashkirs, the Udmurts, the Mordovians, and Siberians. The materials of the paper can be beneficial for anyone interested in the empire, nation, religion and Orthodox missionary policy phenomenon and modern ethno-political processes in the Russian Federation and Europe
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