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91.
The s-wave bound state of the 4α+Λ system is investigated. The relevant solution to the Schrödinger equation is expanded in the basis formed by the eigenfunctions of Hamiltonian for the 4α subsystem. Differential equations for Yakubovsky components are employed to calculate basis functions. Phenomenological potentials for αα and αΛ interactions are used. In the 4α system, additional three-particle potentials for the interaction between α clusters are introduced in such a way as to reproduce the experimental data on the binding energies, the root-mean-square radii, and the charge form factors for the 12C and the 16O nucleus. The binding energy, the root-mean-square radius, and the hyperon distribution in the ground state of the Λ 17 O nucleus are calculated. The results of the calculations are in good agreement with those obtained on the basis of the 16O+Λ two-particle model with the phenomenological Woods-Saxon potential. 相似文献
92.
The cluster-reduction method is used to solve the differential Faddeev equations for S=1/2, T=0 and S=3/2, T=0 spin-isospin states of the Λnp system in the s-wave approximation. The NN interaction is simulated on the basis of the MT I–III potential model, and the ΛN potential is set to V ΛN =V NN /2. This simple option makes it possible to reproduce faithfully the binding energy of the hypertriton Λ 3 H. The doublet and quadruplet Λd scattering lengths and the low-energy phase shifts are calculated. It is shown that the effective-range approximation is applicable to the cases of doublet and quadruplet scattering. 相似文献
93.
V. I. Kodolov I. N. Shabanova L. G. Makarova N. V. Khokhryakov A. P. Kuznetsov O. A. Nikolaeva J. Kerene G. I. Yakovlev 《Journal of Structural Chemistry》2001,42(2):215-219
This paper deals with X-ray photoelectron and electron microscopy studies of the structure of carbon–metal-containing micro- and nanotubulenes. Ab initio quantum-chemical calculations were performed to analyze the possibility and mechanism of tubulene formation. 相似文献
94.
Novikova N. N. Yakovlev V. A. Kucherenko I. V. Karczewski G. Chusnutdinow S. 《JETP Letters》2018,108(7):460-464
JETP Letters - Infrared spectra of reflection and attenuated total reflection of PbTe thin films deposited by molecular beam epitaxy on a GaAs/CdTe substrate have been measured. The high-frequency... 相似文献
95.
Problems of instrumentation for the measurement of C02-1aser pulses at 10.6 vm and of development of a working standard and high-accuracy test equipment are considered.Translated from Voprosy Metrologicheskogo Obsepecheniya Izmereniya Parametrov Tekhnologicheskikh Lazerov, pp. 69–79, 1984. 相似文献
96.
Nezhevenko O.A. Yakovlev V.P. 《IEEE transactions on plasma science. IEEE Nuclear and Plasma Sciences Society》2000,28(3):542-549
A major factor limiting the output power of a high-power magnicon is RF breakdown in its penultimate cavity. Utilization of the principal of angle summing allows us to achieve cumulative interaction between a beam and RF fields of the magnicon deflection system, and thus to decrease the maximum electric field in the penultimate cavity. In this paper, the problems of implementing a cumulative interaction in a magnicon deflecting system are discussed. A deflecting system with coupled cavities working according to the principal of angle summing, which has been tested with success experimentally, has a limitation caused by instabilities that can limit pulse duration at a power level higher than a few tens of milliwatts. The method described employs a set of uncoupled penultimate cavities to obtain cumulative interaction at high power without sacrifice of pulsewidth 相似文献
97.
M. N. Yakovlev 《Journal of Mathematical Sciences》2000,101(4):3355-3360
For implicit functions determined by the equation Tx+F(λ,x)=0, where T is an unbounded operator, existence and differentiability conditions are established. As an application,
the solvability conditions for equations of the form Tx+f(x)=0 are derived.
Translated fromZapiski Nauchnykh Seminarov POMI, Vol. 248, 1998, pp. 216–224.
Translated by L. Yu. Kolotilina. 相似文献
98.
B. Yu. Lalaev I. P. Yakovlev N. N. Kuz’mich G. V. Ksenofontova V. E. Zakhs 《Russian Journal of General Chemistry》2010,80(10):2043-2047
Reactions of 2-alkylsulfanyl- and 2-alkoxy-4-hydroxy-6H-1,3-oxazin-6-ones with oxygen-centered nucleophiles were studied. 2-Alkoxy-4-hydroxy-6H-1,3-oxazin-6-ones reacted with water and alcohols to give the corresponding alkyl 3-amino-3-oxopropanoates as a result of
opening of the oxazine ring at the C6-O bond, whereas their 2-alkylsulfanyl analogs turned out to be stable toward O-nucleophiles. The different reactivities of
the title compounds were interpreted in terms of quantum-chemical calculations of their electronic structure. 相似文献
99.
100.
Novikov D. V. Yakovlev I. P. Zakhs V. E. Prep'yalov A. V. 《Russian Journal of General Chemistry》2001,71(9):1495-1496
Russian Journal of General Chemistry - 相似文献