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1.
Paulo A. Faria da Veiga Michael O'Carroll Emmanuel Pereira Ricardo Schor 《Communications in Mathematical Physics》2001,220(2):377-402
We consider the relaxation to equilibrium of solutions , t>0, , of stochastic dynamical Langevin equations with white noise and weakly coupled Ginzburg–Landau interactions. Using a Feynman–Kac
formula, which relates stochastic expectations to correlation functions of a spatially non-local imaginary time quantum field
theory, we obtain results on the joint spectrum of H, , where H is the self-adjoint, positive, generator of the semi-group associated with the dynamics, and P
j
, j= 1, …, d are the self-adjoint generators of the group of lattice spatial translations. We show that the low-lying energy-momentum
spectrum consists of an isolated one-particle dispersion curve and, for the mass spectrum (energy-momentum at zero-momentum),
besides this isolated one-particle mass, we show, using a Bethe–Salpeter equation, the existence of an isolated two-particle
bound state if the coefficient of the quartic term in the polynomial of the Ginzburg–Landau interaction is negative and d= 1, 2; otherwise, there is no two-particle bound state. Asymptotic values for the masses are obtained.
Received: 27 September 2000 / Accepted: 16 January 2001 相似文献
2.
Quantum dots with a three-dimensional confining potential, i.e. “spherical” quantum dots, are considered with inclusion of
electron-electron interaction (a quantum analog of the Thomson atom). The energy spectrum of two-electron parabolic quantum
dots has been determined by numerical diagonalization of the full Hamiltonian in a one-particle basis.
Fiz. Tverd. Tela (St. Petersburg) 40, 2134–2135 (November 1998) 相似文献
3.
In this paper, several spectroscopic techniques were used to investigate the interaction of engeletin (ELN) with bovine serum
albumin (BSA). The analysis of UV–Vis absorption and fluorescence spectra revealed that ELN and BSA formed a static complex
ELN–BSA, and ELN quenched the fluorescence of BSA effectively. According to the thermodynamic parameters ΔS
0 = 47.27 J·mol−1·K−1 and ΔΗ
0 = −10.34 kJ·mol−1, the hydrophobic and hydrogen bond interactions were suggested to be the major interaction forces between ELN and BSA. Raman
spectroscopy indicated that the binding of ELN slightly changed the conformations and microenviroment of BSA and decreased
the α–helix content of BSA. 相似文献
4.
The specific features of fermion condensation — a phase transition associated with the rearrangement of the one-particle degrees
of freedom in strongly correlated Fermi systems — by which this phenomenon can be detected experimentally are discussed.
Pis’ma Zh. éksp. Teor. Fiz. 65, No. 11, 828–833 (10 June 1997) 相似文献
5.
Ya Li Zhang Ning Hua Zhu Ji Min Wen E. Y. B. Pun P. S. Chung 《Optical and Quantum Electronics》2007,39(15):1289-1296
The variational method is proposed to analyze the influence of the fabrication parameters on the performance of buried K+–Na+ ion-exchanged Er3+–Yb3+ ions co-doped glass waveguide. The unknown parameters of the Hermite–Gaussian functions as the trial field distribution are
determined based on the scalar variational principle. It is demonstrated that the results calculated in this paper agree with
those measured in the experiment. The mode dimensions, the effective refractive index, and the overlap factor as the functions
of the fabrication parameters are investigated. These results of the variational analysis are useful for the design and optimization
of Er3+–Yb3+ ions co-doped waveguides. 相似文献
6.
V. K. Voronkova R. T. Galeev L. V. Mingalieva G. Novitchi 《Applied magnetic resonance》2008,33(1-2):73-84
For the first time the exchange interaction between copper and non-Kramers Tb3+ ions was studied by means of electron paramagnetic resonance (EPR). Features of the manifestation of this interaction in
the EPR spectra of dimer fragments Cu–Tb and pentanuclear fragments Cu–Tb–Cu–Tb–Cu are analyzed. The possibility to determine
the sign and value of this interaction from EPR spectra for the case when the lowest states of Tb3+ are the states |0〉, | ± 1〉 is shown. The exchange interaction between copper and trivalent terbium ions in the studied pentanuclear
complex is ferromagnetic.
Authors' address: Violeta K. Voronkova, Kazan Physical-Technical Institute, Russian Academy of Sciences, Sibirsky trakt 10/7,
Kazan 420029, Russian Federation 相似文献
7.
I. Hamamoto 《The European physical journal. Special topics》2007,150(1):123-126
Both
positive-energy and weakly-bound one-particle levels for neutrons in
Y20 deformed Woods-Saxon potentials are examined in comparison with those
in spherical Woods-Saxon potentials.
While s1/2 levels play a unique role in spherical drip-line nuclei,
the Ωπ = 1/2+ levels in Y20 deformed potentials,
which always contain some amount of s1/2 component, exhibit an
important role in deformed drip-line nuclei.
As the potential strength becomes weaker, some weakly-bound
Ωπ = 1/2+ levels continue to the positive-energy region as
one-particle resonant levels, while others have no such continuation.
Among an infinite number of one-particle levels at a given positive-energy
and in a given deformed potential, only some selected levels expressed
in terms of eigenphase
are found to be important in the pair-correlated ground state of
neutron-drip-line nuclei. 相似文献
8.
A. V. Zakharov 《Journal of Experimental and Theoretical Physics》1997,85(4):627-634
The present paper is a direct continuation of an earlier paper [JETP 83, 1 (1996)] devoted to the derivation of the macroscopic Einstein equations to within terms of second order in the interaction
constant. Ensemble averaging of the microscopic Einstein equations and the Liouville equation for the random functions leads
to a closed system of macroscopic Einstein equations and kinetic equations for one-particle distribution functions. The macroscopic
Einstein equations differ from the classical equations in that their left-hand side contains additional terms due to particle
interaction. The terms are traceless tensors with zero divergence. An explicit covariant expression for these terms is given
in the form of momentum-space integrals of expressions dependent on one-particle distribution functions of the interacting
particles of the medium. The given expressions are proportional to the cube of the Einstein constant and the square of the
particle number density. The latter relationship implies that interaction effects manifest themselves in systems of very high
density (the universe in the early stages of its evolution, dense objects close to gravitational collapse, etc.)
Zh. éksp. Teor. Fiz. 112, 1153–1166 (October 1997) 相似文献
9.
S. N. Golyandin K. V. Sapozhnikov Yu. A. Emel’yanov A. B. Sinani S. P. Nikanorov S. B. Kustov W. H. Robinson 《Physics of the Solid State》1998,40(10):1667-1671
The dislocation amplitude-dependent friction (ADIF) of high-purity (99.999%) polycrystalline aluminum is investigated in the
temperature range 7–300K at vibrational strain amplitudes of 10−7–10−4 for samples in the annealed and deformed (by quasistatic, shock, and ultrasonic loading) states. The ADIF is a multistage
effect in the indicated temperature and vibration amplitude ranges. Analysis of the amplitude-temperature spectra of the ADIF
permits separation of components attributable to: interaction between dislocations, the interaction of dislocations with pinning
points, and pure dislocation relaxation (the interaction of dislocations with the Peierls relief). ADIF is observed to depend
nonmonotonically on the initial quasistatic strain determined by strain hardening and recovery processes.
Fiz. Tverd. Tela (St. Petersburg) 40, 1839–1844 (October 1998) 相似文献
10.
We consider the time evolution of a system of N identical bosons whose interaction potential is rescaled by N
−1. We choose the initial wave function to describe a condensate in which all particles are in the same one-particle state.
It is well known that in the mean-field limit N → ∞ the quantum N-body dynamics is governed by the nonlinear Hartree equation. Using a nonperturbative method, we extend previous results on
the mean-field limit in two directions. First, we allow a large class of singular interaction potentials as well as strong,
possibly time-dependent external potentials. Second, we derive bounds on the rate of convergence of the quantum N-body dynamics to the Hartree dynamics. 相似文献
11.
We have analyzed the structure of the energy spectrum of the Am3+ ion in LaCl3 in the weak and intermediate configuration interaction approximation. We have established that in the intermediate configuration
interaction approximation, the mean-square deviation of the calculated values of the Stark level energies from the experimental
values is 53% smaller than in the weak configuration interaction approximation. We have determined the even and odd crystal
field parameters and the covalency parameters. We conclude that based on analysis of the Stark structure of the energy spectrum,
we can make quantitative estimates of the intensity characteristics.
__________
Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 73, No. 5, pp. 637–640, September–October, 2006. 相似文献
12.
B. Ananthanarayan S.D. Rindani 《The European Physical Journal C - Particles and Fields》2006,46(3):705-712
We approach the issue of the discovery of new physics at high energies associated with the proposed International Linear
Collider in the presence of longitudinal as well as transverse electron and positron beam polarization. We determine the beam
polarization dependence and the angular distribution of a particle of arbitrary spin in a one-particle inclusive final state
produced in e+e- collisions through the interference of γ or Z amplitude with the amplitude from new interactions having arbitrary space–time
structure. We thus extend the results of Dass and Ross, proposed at the time of the discovery of neutral currents, to beyond
the standard model currents. We also extend the case of e+e- annihilation in the s-channel to the production of bosons due to t- and u-channel processes. Our work provides an approach
to model-independent determination of the space–time structure of beyond the standard model interactions. We briefly discuss
applications of the framework to popular extensions of the standard model, and demonstrate that our framework is general enough
to account for certain results in the minimal supersymmetric standard model. 相似文献
13.
R. M. Vlasova N. V. Drichko O. O. Drozdova R. N. Lyubovskaya 《Physics of the Solid State》1997,39(8):1165-1170
The reflection spectra and optical conductivity spectra of the new organic conductor ϰ-(ET)2[Hg(SCN)2Cl] with a metal-insulator transition in the spectral regions 700–5500 and 9000–40 000 cm−1 have been studied in polarized light at 300 K. A comparisonis made between the spectra obtained and the corresponding spectra
of related isostructural conductors based on the ET molecule, and also the properties of the crystal structure of the investigated
compounds. An electronic transition between the ET molecules of the dimer (ET)
2
+
in the spectral region 700–5500 cm−1 has been identified, as have the features of the electronic-vibrational structure arising as a consequence of the interaction
of this transition with the completely symmetric intramolecular vibrations of the ET molecule. It is found that the conductor
with the stronger dimer interaction between the ET molecules has the higher the transition temperature.
Fiz. Tverd. Tela (St. Petersburg) 39, 1313–1319 (August 1997) 相似文献
14.
Vadim Rodin Amand Faessler Fedor Šimkovic Petr Vogel 《Czechoslovak Journal of Physics》2006,56(5):495-503
The nuclear matrix elements M
0ν
of the neutrinoless double-beta decay (0νβ β) of most nuclei with known 2νββ-decay rates are systematically evaluated using the Quasiparticle Random Phase Approximation (QRPA) and Renormalized QRPA
(RQRPA). The experimental 2νβ β-decay rate is used to adjust the most relevant parameter, the strength of the particle-particle interaction. With such procedure
the M
0ν
values become essentially independent of single-particle basis size, the axial vector quenching factor, etc. Theoretical
arguments in favor of the adopted way of determining the interaction parameters are presented. It is suggested that most of
the spread among the published M
0ν
’s can be ascribed to the choices of implicit and explicit parameters, inherent to the QRPA method.
Presented by V. Rodin at the Workshop on calculation of double-beta-decay matrix elements (MEDEX’05), Corfu, Greece, September
26–29, 2005. 相似文献
15.
Prediction and Measurement of Electron Density and Collision Frequency in a Weakly Ionised Pine Fire
Kgakgamatso Mphale Mohan Jacob Mal. Heron 《International Journal of Infrared and Millimeter Waves》2007,28(3):251-262
Pine litter flame is a weakly ionised medium. Electron-neutral collisions are a dominant form of particle interaction in the
flame. Assuming flame electrons to be in thermal equilibrium with neutrals and average electron-neutral collision frequency
to be much higher than the plasma frequency, the propagation of microwaves through the flame is predicted to suffer signal
intensity loss. A controlled fire burner was constructed where various natural vegetation species could be used as fuel. The
burner was equipped with thermocouples and used as a cavity for microwaves with a laboratory quality network analyzer to measure
wave attenuation. Electron density and collision frequency were then calculated from the measured attenuation. The parameters
are important for numerical prediction of electromagnetic wave propagation in wildfire environments. A controlled pine litter
fire with a maximum flame temperature of 1080 K was set in the burner and microwaves (8–10.5 GHz) were caused to propagate
through the flame. A microwave signal loss of 1.6–5.8 dB was measured within the frequency range. Based on the measured attenuation,
electron density and electron-neutral collision frequency in pine fire were calculated to range from 0.51–1.35 × 1016 m−3 and 3.43–5.97 × 1010 s−1 respectively. 相似文献
16.
Quantum mechanics equations for a system of the Bose particles are represented in the form of material field equations. A
nonlinear equation for the macroscopic one-particle wave function is derived. Using the Krylov–Bogolyubov–Mitropol’skii method
for equations in partial derivatives, nonlinear waves in the Bose–Einstein condensate are investigated. In the cubic approximation,
dispersion relations for waves are derived and nonlinear frequency shift is calculated in the first- and third-order approximations
for the interaction radius. 相似文献
17.
E. Liénard G. Ban J. Blieck D. Durand F. Duval X. Fléchard M. Herbane M. Labalme Y. Lemière F. Mauger A. Méry O. Naviliat-Cuncic D. Rodríguez J. C. Thomas 《Hyperfine Interactions》2006,172(1-3):29-33
We report on the status of the LPCTrap experiment, devoted to measure the β–ν angular correlation in the pure Gamow–Teller
decay of 6He. This measurement is motivated by the search for the presence of tensor type contributions to the weak interaction. The
6He ions are confined in a novel transparent Paul trap. The β particles and the recoil ions are detected in coincidence to
deduce the angular correlation parameter. The commissioning run performed in 2005 has given the proof of principle of this
experiment. Up to 105 coincidences were recorded during a second run in 2006. 相似文献
18.
V. M. Astashynski E. A. Kostyukevich A. M. Kuzmitski A. A. Mishchuk P. N. Shoronov 《Journal of Applied Spectroscopy》2012,79(4):610-615
The dynamics of the interaction of two oppositely directed plasma flows generated by miniature gas-discharge magnetoplasma compressors is studied. The maximum plasma electron temperature and density in the region where the plasmas interact are found to be 4.5 eV and 1.4⋅1017 cm–3. Exposure of samples to this kind of plasma near the interaction region leads to an energy flux at the surface of 2–8 J/cm2, which is sufficient for modification of the surface properties of various materials. 相似文献
19.
20.
Grafted natural rubber-based polymer electrolytes: ATR-FTIR and conductivity studies 总被引:2,自引:0,他引:2
Attenuated total reflectance–Fourier transformed infrared spectroscopy measurement is employed to study the interactions between
the components of 30% methyl-grafted natural rubber (MG30), lithium trifluromethanesulfonate (LiCF3SO3 or LiTF), and propylene carbonate (PC). Vibrational spectra data of LiTF reveals that the νs(SO3) at 1,045 cm−1, δs(CF3) at 777 cm−1, and C=O stretching mode at 1,728 cm−1 for MG30 have shifted to lower wave numbers in MG30–LiTF complexes indicating that complexation has occurred between MG30
and LiTF. The solvation of lithium ion is manifested in Li+ ← O=C interaction as shown by the downshifting and upshifting of C=O mode at 1,788 to 1,775 cm−1 and νas(SO3) at 1,250 to 1258 cm−1, respectively, in LiTF–PC electrolytes. There is no experimental evidence of the interaction between MG30 and PC. Competition
between MG30 and PC on associating with lithium ion is studied, and the studies show that the interaction between MG30–LiTF
is stronger than that of the PC–LiTF in plasticized polymer–salt complexes. The effect of PC on the ionic conductivity of
the MG30–LiTF system is explained in terms of the polymer, plasticizer, and salt interactions. The temperature dependence
of conductivity of the polymer films obeys the Vogel–Tamman–Fulcher relation. Values of conductivity and activation energy
of the MG30-based polymer electrolyte systems are presented and discussed. 相似文献