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101.
A. S. Borisov A. V. Vargasov Z. M. Guseva V. G. Denisova E. A. Kanevskaya V. M. Maksimenko V. S. Puchkov S. E. Pyatovskii S. A. Slavatinskii 《Bulletin of the Russian Academy of Sciences: Physics》2007,71(4):516-518
γ Families with halos detected in the “Pamir” experiment have been analyzed. Comparison of the experimental data with the results of calculation within the quark-gluon string model (MC0 code) made it possible to determine the efficiency of halo formation by protons, α particles, and heavy nuclei, as well as the fraction of protons in the mass composition of primary cosmic rays at an energy of 1016 eV. It is shown that halos are formed predominantly by protons. The fraction of protons in the mass composition of primary cosmic rays at an energy of 1016 eV is 20%. 相似文献
102.
Consider the problem of rolling a dynamically asymmetric balanced ball (the Chaplygin ball) over a sphere. Suppose that the
contact point has zero velocity and the projection of the angular velocity to the normal vector of the sphere equals zero.
This model of rolling differs from the classical one. It can be realized, in some approximation, if the ball is rubber coated
and the sphere is absolutely rough. Recently, J. Koiller and K. Ehlers pointed out the measure and the Hamiltonian structure
for this problem. Using this structure we construct an isomorphism between this problem and the problem of the motion of a
point on a sphere in some potential field. The integrable cases are found.
相似文献
103.
K. Gjurova Chr Bechev K. Troev G. Borisov 《Journal of Thermal Analysis and Calorimetry》1986,31(4):853-864
By means of a combined thermal analysis technique, the thermal behaviour of rigid polyurethane foams containing additive antipyrenes was studied. The presence of phosphorus- and phosphorus/chlorine-containing antipyrenes based on phosphate and phosphonate and a combination of them led to decreases in the rates of heat and weight loss during heating. More steps of decomposition were formed and the interval of decomposition was widened and shifted to higher temperatures. Some thermal characteristics make it possible to predict the optimum antipyrene compositions and concentrations with minimum time, labour and material consumption under laboratory conditions.
Zusammenfassung Mittels einer kombinierten Technik wurde das thermische Verhalten eines starren, Antipyrene als Additiv enthaltenden Polyurethanschaumes untersucht. Phosphor und Phosphor/Chlor enthaltende Antipyrene auf Phosphat- und Phosphonatbasis und eine Kombination dieser Substanzen vermindern die Geschwindigkeit der Wärmeentwicklung und des Gewichtsverlustes während des Aufheizvorganges. Es treten mehr Zersetzungsschritte auf und das Temperaturintervall der Zersetzung ist größer und nach höheren Temperaturen hin verschoben. Einige thermische Kennwerte ermöglichen die Voraussage der optimalen Zusammensetzung und Konzentration des Antipyren-Additivs für minimalen Zeit-, Arbeits- und Materialaufwand unter Laboratoriumsbedingungen.
, . /- , . , . .相似文献
104.
The propagation of elastic waves in an arbitrary direction through a hexagonal piezoelectric crystal is investigated. Orientational relations are obtained in analytic form for the effective elastic moduli and the piezoelectric and dielectric constants, and also for the basic parameters of the elastic waves: the phase velocity, electromechanical coefficient, and the divergence between the displacement vector and the energy flux. Expressions are given for the directions in which the electromechanical coefficient takes an extremal value, and the basic parameters are calculated for cadmium sulfide.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 5, pp. 101–105, May, 1977. 相似文献
105.
V. I. Galkin A. S. Borisov R. Bakhromzod V. V. Batraev S. Z. Latipova A. R. Muqumov 《Moscow University Physics Bulletin》2018,73(2):179-186
A method for estimation of the parameters of the primary particle of an extensive air shower (EAS) by a high-altitude detector complex is described. This method was developed as part of the Pamir-XXI project. The results may be useful for other high-altitude projects and the EAS method in general. The specific configurations of optical detectors for Cherenkov EAS radiation and charged-particle detectors, the methods for data processing, and the attainable accuracy of reconstruction of parameters of primary particles (energy, direction, mass/type) are presented. The results primarily cover optical detectors that are suitable for studying EASs from primary nuclei in the range of energies E0 = 100 TeV–100 PeV and showers from primary γ-quanta with energies of Eγ ≥ 30 TeV. Grids of charged-particle detectors designed to determine the EAS direction and energy in the E0 = 1 PeV–1 EeV range are also considered. The obtained accuracy estimates are the upper limits of the actual experimental accuracies. 相似文献
106.
107.
A. V. Fokin N. P. Vorob'eva Yu. A. Borisov A. F. Kolomiets 《Russian Chemical Bulletin》1989,38(11):2330-2334
A theoretical quantum-chemical analysis of the interaction of xenobiotics of the dioxin type with a model of their receptor in the ground state supports the possibility of forming rather stable substrate-receptor pairs, with not only oxidized but also reduced cytochrome P-450. General features have been identified in the interaction of the most dangerous xenobiotics of the dioxin type with the model of their receptor.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 11, pp. 2540–2544, November, 1989. 相似文献
108.
F. I. Zubkov E. V. Nikitina K. F. Turchin A. A. Safronova R. S. Borisov A. V. Varlamov 《Russian Chemical Bulletin》2004,53(4):860-872
The intramolecular Diels—Alder reaction of readily accessible 4-substituted 4-(N-furfuryl)aminobut-1-enes was studied and a new one-step method was developed for the synthesis of 6,8a-epoxy-1,2,3,4,4a,5,6,8a-octahydroisoquinoline (3-aza-11-oxatricyclo[6.2.1.01,6]undec-9-ene) derivatives. The [4+2]-cycloaddition proceeds stereoselectively to form exo-adducts. The influence of substituents at the nitrogen atom in 4-(N-furfuryl)aminobut-1-enes on the cycloaddition pathway was examined. 相似文献
109.
A. V. Varlamov D. G. Grudinin A. I. Chernyshev A. N. Levov I. Yu. Lobanov R. S. Borisov F. I. Zubkov 《Russian Chemical Bulletin》2004,53(8):1711-1716
5-Methyl-4,5-dihydro-3H-spiro[benzo-2-azepine-3,1-cyclohexane] N-oxide was rear- ranged into 5-methyl-1-oxo-1,2,4,5-tetrahydro-3H-spiro[benzo-2-azepine-3,1-cyclohexane]. The latter was used for the synthesis of spiro{triazolo[3,4-a]- and-tetrazolo[5,1-a]benzo-2- azepinecyclohexanes}.Published in Russian in Izvestiya Akademii Nauk.
Seriya Khimicheskaya, No. 8, pp. 1647–1651, August, 2004. 相似文献
110.
N. V. Pervukhina S. V. Borisov S. A. Magarill D. Yu. Naumov V. I. Vasiliev B. G. Nenashev 《Journal of Structural Chemistry》2004,45(4):720-723
The results of structural studies of the synthetic analog of the radtkeite mineral Hg3S2Cl1.00I1.00 are analyzed. The crystal structure of the compound has been refined; the unit cell parameters are a
m = 16.827(4) , b
m = 9.117(1) , c
m = 13.165(5) , = 130.17(2)°, V = 1543.3(8) 3, space group C2/m, Z = 8, R = 0.0527. A possible transition a
0
= a
m; b
0
= a
m + 2c
m; c
0
= –b
m to the pseudo-orthorhombic F cell previously determined for radtkeite, where one of the angles (
0
) is slightly different from 90° (89.55°), has been found. Each sulfur atom in the structure is bonded to three mercury atoms, forming SHg3 umbrellas with distances 2.240(6) –2.474(8) and angles HgSHg 94.7(2)°–102.9(2)°. The SHg3 fragments are linked through Hg vertices to form corrugated [Hg12S8] layers. The halogen atoms lie inside and between the [Hg12S8] layers; the distances are Hg-Cl and Hg-I 2.783(7) , 2.961(7) , and 3.083(4) –3.311(3) , respectively.Original Russian Text Copyright © 2004 by N. V. Pervukhina, S. V. Borisov, S. A. Magarill, D. Yu. Naumov, V. I. Vasiliev, and B. G. NenashevTranslated from Zhurnal Strukturnoi Khimii, Vol. 45, No. 4, pp. 755–758, July–August, 2004.This revised version was published online in April 2005 with a corrected cover date. 相似文献