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91.
We propose new method which allows determination of the strange-sea quark spin distribution in the nucleon through measurement of various inclusive and semi-inclusive polarized deep inelastic electron–proton or muon–proton reactions. It is shown, that using combinations of inclusive data and semi-inclusive data containing neutral pions in the final state, it is possible to extract the strange-sea quark spin distribution. Similar result can be obtained for charged pions and some other hadrons also. 相似文献
92.
93.
G. G. Melikyan A. B. Sargsyan V. S. Giri R. T. Grigoryan Sh. O. Badanyan 《Chemistry of Heterocyclic Compounds》1988,24(3):258-263
The regiochemistry of the reaction of 1,2- and 1-substituted derivatives of 1-buten-3-yne and its 4- and 2,4-substituted derivatives of the isoprenoid type with acetoacetic ester and acetylacetone in the presence of the manganese(III) acetate-copper(II) acetate oxidative system was studied. Derivatives of 4,5-dihydrofuran, furan, and hexahydrobenzofuran were obtained.Communication 137 from the series Reactions of unsaturated compounds. See [1] for communication 136.Translated from Khimiya Geterotsiklicheskikh Soedinenii, Vol. 24, No. 3, pp. 317–323, March, 1988. 相似文献
94.
R. R. Grigoryan S. D. Arsentiev A. A. Mantashyan 《Reaction Kinetics and Catalysis Letters》1985,29(1):187-193
Kinetic regularities in the consumption of initial reactants and the accumulation of propylene oxidation products has been studied in the region of negative temperature coefficients of the maximum reaction rate (T=648–723 K). It has been revealed that for prolynene-enriched mixtures (C3H6:O2=3:1) at P-20.66 kPa, the reaction rate is practically independent of the temperature, whereas for poor mixtures (C3H6:O2=1:5) it decreases with increasing temperature.
a (T=648–723K). , (C3H6:O2=3:1) P=20,66 , (C3H6:O2=1:5) .相似文献
95.
Babakhanyan A. V. Shakhbazyan L. G. Grigoryan Dzh. V. Kocharyan S. T. 《Russian Journal of Organic Chemistry》2003,39(9):1227-1230
Stevens rearrangement of ammonium salts containing an allyloxycarbonylmethyl group in benzene in the presence of sodium phenoxide yields allyl 2-dialkylamino-4-pentenoates. The rearrangement in the presence of sodium methoxide is accompanied by transesterification to afford methyl 2-dialkylamino-4-pentenoates. 相似文献
96.
Doklady Mathematics - We obtain new bounds and exact values of the minimum number of cubes with side length $$\varepsilon \in (0,\;1)$$ covering the torus... 相似文献
97.
A. M. Basharov G. G. Grigoryan N. V. Znamenskiy E. A. Manykin Yu. V. Orlov A. Yu. Shashkov T. G. Yukina 《Journal of Experimental and Theoretical Physics》2006,102(2):206-219
The spiky structure of the spontaneous emission from praseodymium ions in the LaF3 lattice on the 3P0-3H6 transition under coherent pulsed excitation of the adjacent 3H4-3P0 transition has been studied experimentally and theoretically. The experimental results are in good agreement with the theoretical conclusions based on analysis of the emission dynamics of an excited ensemble of three-level systems in the mean field approximation. The generation of a spiky structure is interpreted as the emission of a cnoidal wave pulse. The recorded random pattern of time intervals between the spikes reflects the sensitivity of the cnoidal wave period to fluctuations in the system. The developed theory has been found to be related to models of deterministic chaotic dynamics. 相似文献
98.
K. E. Avjyan G. H. Vardanyan R. P. Grigoryan A. M. Khachatryan 《Journal of Contemporary Physics (Armenian Academy of Sciences)》2008,43(3):139-141
With use of the vacuum pulsed-laser deposition technique an isotype nInSb-nPbTe-nCdTe structure is fabricated. Spectral dependence of photoresponse of the obtained structure is studied at the temperature 120 K. In the curve of spectral dependence a change in the sign of photoresponse is observed for both zero bias and external voltage. Qualitative explanation of this phenomenon is given. 相似文献
99.
N. M. Agababyan V. V. Ammosov M. Atayan N. Grigoryan H. Gulkanyan A.A. Ivanilov Zh. Karamyan V. A. Korotkov 《Physics of Atomic Nuclei》2007,70(11):1904-1912
The characteristics of the charged-current neutrino—nuclear interactions are investigated for the first time at E
ν
= 1–3 GeV using the data obtained with SKAT propane-freon bubble chamber irradiated in the neutrino beam at the Serpukhov
accelerator. The E
ν
dependence of the mean multiplicities of different types of secondary particles and their multiplicity, momentum, and angular
distributions are measured.
The text was submitted by the authors in English. 相似文献
100.
L.?Grigoryan P.?Petrosyan S.?PetrosyanEmail author V.?Bellani F.?Maglia 《The European Physical Journal B - Condensed Matter and Complex Systems》2003,34(4):415-419
The optical transmission spectra of CdSe
x
S1-x
doped low viscosity silicate glass are experimentally studied. Glass samples were subjected to one- or multi-step heat treatment for different lengths of time. We have followed the modification of the absorption spectra after each heat treatment. The red shift of the absorption edge and the accompanying change of coloration from orange to red are explained by size-quantization effects in the energy spectrum of electrons and holes in semiconductor nanoparticles thermally developed in low viscosity glass matrix. X-ray diffraction data show no stoichiometry changes during the heat treatment processes. Crystallites composition (
) defined from the diffraction peaks was very close to the value estimated from the position of absorption edge.Received: 14 March 2003, Published online: 9 September 2003PACS:
79.60.Jv Interfaces; heterostructures; nanostructures - 78.20.Ci Optical constants (including refractive index, complex dielectric constant, absorption, reflection and transmission coefficients, emissivity) - 78.40.Fy Semiconductors 相似文献