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101.
102.
A. V. Vosmerikov V. I. Zaikovskii L. L. Korobitsyna V. V. Kozlov N. V. Arbuzova S. P. Zhuravkov 《Kinetics and Catalysis》2011,52(3):427-433
Nonoxidative methane conversion into aromatic hydrocarbons over ZSM-5-type high-silica zeolites modified with nanosized powders
of molybdenum (4.0 wt %) and silver (0.1–0.5 wt %) is reported. The acidic properties of the catalysts have been investigated
by temperature-programmed ammonia desorption. The microstructure and composition of the Ag-Mo/ZSM-5 catalytic systems have
been studied by high-resolution transmission electron microscopy and energy-dispersive X-ray spectroscopy. The doping of the
Mocontaining zeolite with silver enhances its activity and stability in nonoxidative methane conversion into aromatic hydrocarbons. 相似文献
103.
V. A. Semenov Zh. A. Kozlov L. Krachun G. Mateescu V. M. Morozov A. I. Oprea K. Oprea A. V. Puchkov 《Physics of the Solid State》2010,52(5):988-991
The temperature dependence of the frequency spectrum of tantalum in the temperature range from room temperature to 2300 K
has been studied for the first time using inelastic slow-neutron scattering. The inelastic slow-neutron scattering spectra
have been measured at different temperatures on a DIN-2PI time-of-flight spectrometer installed at the IBR-2 nuclear reactor
(Joint Institute for Nuclear Research, Dubna, Russia) with the use of a TS3000K high-temperature thermostat. From the measured
spectra, the frequency spectra of the tantalum crystal lattice have been determined at temperatures of 293, 1584, and 2300
K by the iteration method. As the temperature increases, the frequency spectrum, on the whole, is softened and the specific
features manifested themselves at room temperature are smoothed. The variations observed have been explained by the increase
in the role of the effects of vibration anharmonism at high temperatures. 相似文献
104.
It is proved that faces of the unit spheres of the mass and comass norms are totally geodesic submanifolds in the manifolds of the extreme points of the spheres. A canonical embedding of the complex projective space
in the Plücker model of the Grassmannian
is described, and some of the properties of the embedding are proved. As an application of these results, the 2-dimensional sections in
having minimal curvature are characterized geometrically. Bibliography: 16 titles. 相似文献
105.
The a(1) state of PbO can be used to measure the electric dipole moment of the electron d(e). We discuss a semiempirical model for this state, which yields an estimate of the effective electric field on the valence electrons in PbO. Our final result is a lower limit on the measurable energy shift, which is significantly larger than was anticipated earlier: 2/W(d)/d(e)>or=2.4x10(25) Hz[d(e) divided by e cm]. 相似文献
106.
We report the derivation of a wave equation for coherence in "dark state" two-photon-resonance spectroscopy. One of its consequences is a dark state area theorem. The dark area theorem is a single ordinary differential equation which is globally equivalent, in a way we describe, to the full set of five coupled nonlinear partial differential equations that govern space-time evolution of two-pulse coherence in a lambda medium. The predictions of the dark area theorem are open to test via laser spectroscopy in dilute vapors and inhomogeneously broadened solids. 相似文献
107.
Yu. V. Kozlov S. V. Khaltourtsev I. N. Machulin A. V. Martemyanov V. P. Martemyanov A. A. Sabelnikov V. G. Tarasenkov E. V. Turbin V. N. Vyrodov 《Physics of Atomic Nuclei》2002,65(7):1219-1221
The results of studying antineutrino interactions with deuterons (CCD and NCD reactions) and hydrogen (CCP) at the Krasnoyarsk underground reactor with the Deuteron detector are presented. The cross sections for NCD and CCD were measured with a precision of 9%. For CCP, the precision is 3%: σ expt NCD =(3.35±0.31)×10?44 cm2/fission 235U, σ expt NCD =(1.08±0.09)×10?44 cm2/fission 235U, and σ expt NCD =(6.39±0.19)×10?43 cm2/fission 235U. The precision of the experimental results is close to the theoretical one and is in good agreement with other experiments. The limit on the parameters of antineutrino oscillations into the sterile state was obtained: Δm 2≤4.7×10?2 eV2 for sin2(2?)=1.0 (68% C.L.). A comparison of the measured and theoretical cross section gives us the neutron-neutron scattering length of a nn(S)=?17±6 fm in the approach of zero momentum transfers. The weak neutral current constant is in good agreement with the prediction of the Standard Model: G A NC =G A CC /0.932±0.056. 相似文献
108.
109.
All-fiber coherent beam combining of fiber lasers 总被引:10,自引:0,他引:10
One half of a 2x2 fused taper single-mode fiber coupler is used for the all-fiber spatial and spectral beam combining of two fiber lasers. 相似文献
110.
Within the framework of the mechanics of heterogenous media, the flow of a mixture of high-pressure gas and an initially close-packed disperse phase from a cylindrical channel of finite dimensions into the atmosphere is investigated numerically. The physical picture is analyzed and the characteristic stages of the process are established. Experimental data indicating satisfactory agreement between the mathematical model and the phenomenon investigated are presented.St.-Petersburg. Translated from Izvestiya Rossiiskoi Akademii Nauk, Mekhanika Zhidkosti i Gaza, No. 3, pp. 60–66, May–June, 1996. 相似文献