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1.
N. T. Ul'chenko N. P. Bekker T. V. Chernenko N. K. Yuldasheva A. I. Glushenkova 《Chemistry of Natural Compounds》2003,39(3):249-252
Seed characteristics and the lipid and fatty-acid compositions were determined for the new cotton varieties ASh-25, Omad, 9771-I, Termez-43, and Bukhara-6. 相似文献
2.
3.
《Physics letters. A》2014,378(16-17):1085-1090
The formations of n-order two-soliton bound states (TSBSs) in the Bose–Einstein condensates with spatiotemporally modulated nonlinearities are studied. Exact analytical expressions of the n-order TSBSs are derived by means of the similarity transformations. Further, the numerical simulations are carried out, consistent with the analytical results very well. The stability analysis shows that the solutions can be stable. Our results indicate that the attractive spatiotemporal inhomogeneous nonlinearities can support n-order TSBSs, which has the potential applications to the generation of matter-wave bright solitons in harmonic traps. 相似文献
4.
The quantum dynamics of carriers bound to helical tube surfaces is investigated in a thin-layer quantization scheme. By numerically solving the open-boundary Schrödinger equation in curvilinear coordinates, geometric effect on the coherent transmission spectra is analysed in the case of single propagating mode as well as multimode. It is shown that, the coiling endows the helical nanotube with different transport properties from a bent cylindrical surface. Fano resonance appears as a purely geometric effect in the conductance, the corresponding energy of quasibound state is obviously influenced by the torsion and length of the nanotube. We also find new plateaus in the conductance. The transport of double-degenerate mode in this geometry is reminiscent of the Zeeman coupling between the magnetic field and spin angular momentum in quasi-one-dimensional structure. 相似文献
5.
Jean Richert 《Physica B: Condensed Matter》2012,407(4):729-734
The propagation of an external transverse magnetic signal acting locally on a 1d chain of spins generates a disturbance which runs through the system. This quantum effect can be interpreted as a classical travelling wave which contains a superposition of a large set of frequencies depending on the size of the chain. Its local amplitude fixes the size of the z-component of the spins at any location in the chain. The average and maximum value of the group velocity are determined and compared with the transmission velocity fixed by the Lieb-Robinson upper bound inequality. 相似文献
6.
Bound states of the Klein-Gordon and Dirac equations for scalar and vector harmonic oscillator potentials
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We give the exact bound states of the Klein-Gordon and Dirac equations with equal scalar and vector harmonic oscillator potentials. 相似文献
7.
Jií Mare 《Nuclear Physics A》2008,804(1-4):296
Self-consistent calculations of single -nuclear states and multi -nuclear states are briefly reviewed. Dynamical effects for deeply bound nuclear states are studied within the relativistic mean-field (RMF) approach. By varying the strength of -nucleus interaction, we cover a wide range of binding energies . Our calculations provide a lower limit on the widths of nuclear bound states for binding energy in the range . Substantial polarization is found in light nuclei for deeply bound nuclear states, with central nuclear densities about twice higher than for the corresponding nuclei without . Multi- nuclear calculations indicate that the binding energy per meson saturates upon increasing the number of mesons embedded in the nuclear medium. The nuclear and densities increase only moderately and are close to saturation, with no indication of any kaon-condensation precursor phenomena. 相似文献
8.
Johann Zmeskal 《Progress in Particle and Nuclear Physics》2008,61(2):512-550
Strong interaction processes were intensively studied at low energy with exotic atoms, touching one of the fundamental problems in hadron physic today — the still unsolved question of how hadron masses are generated. The question of the origin of the large hadron masses made up of light quarks, the current mass of the up (u) and down (d) quarks (mu,d≈5 MeV) is two orders of magnitude smaller than a typical hadron mass of about 1 GeV, will be discussed in the context with the experimental work done in the field of exotic atoms expanded to exotic nuclei.An overview of the properties of exotic hydrogen atoms made of pions and kaons are presented, using high precision experiments unrevealing the nature of strong interaction physics at low energy. A new field which contributes to the understanding of the origin of the large hadron mass is the study of the mass modification in a nuclear medium. Antikaon mediated bound nuclear systems would be an ideal tool, if they exist, to look for chiral restoration at high density and zero temperature or even more exotic to look for phase transitions. 相似文献
9.
The claim of Mohapatra and Maharana thattb(s) is a better scaling variable thant(lns)2 is put to test in the case of Λ-p scattering, after parametrizingb(s) asC
1 +C
2(lns)α. It was observed that in this case the data also prefer anα value which is close to those obtained by Mohapatra and Maharana for other scattering processes. 相似文献
10.
In this paper, new lower bounds for the asymmetric travelling salesman problem are presented, based on spanning arborescences. The new bounds are combined in an additive procedure whose theoretical performance is compared with that of the Balas and Christofides procedure (1981). Both procedures have been imbedded in a simple branch and bound algorithm and experimentally evaluated on hard test problems. 相似文献