共查询到20条相似文献,搜索用时 31 毫秒
1.
Nurkeeva ZS Mun GA Khutoryanskiy VV Bitekenova AB Dubolazov AV Esirkegenova SZh 《The European physical journal. E, Soft matter》2003,10(1):65-68
The critical pH values for hydrogen-bonded interpolymer complexes of poly(N-vinylpyrrolidone) and poly(acrylic acid) in aqueous
solutions were determined. The effect of polymer concentrations, molecular weights and addition of inorganic salts (NaCl and
KCl) on the complexation was studied.
Received 29 April 2002 and Received in final form 24 June 2002 Published online: 21 January 2003 相似文献
2.
D.A. Garanin E.M. Chudnovsky 《The European Physical Journal B - Condensed Matter and Complex Systems》2002,28(1):3-7
We compute the width and shape of the EPR and tunneling resonances due to dislocations in Mn12 acetate crystals. Uncorrelated dislocations produce the Gaussian shape of resonances while dislocations bound in pairs produce
the Lorentzian shape. We stress that the uniaxial spin Hamiltonian together with crystal defects can explain the totality
of experimental data on Mn12.
Received 2 August 2001 / Received in final form 15 March 2002 Published online 17 September 2002 相似文献
3.
P. Schwab R. Raimondi 《The European Physical Journal B - Condensed Matter and Complex Systems》2002,30(1):5-8
We consider non-equilibrium transport in disordered conductors. We calculate the interaction correction to the current for
a short wire connected to electron reservoirs by resistive interfaces. In the absence of charging effects we find a universal
current-voltage-characteristics. The relevance of our calculation for existing experiments is discussed as well as the connection
with alternative theoretical approaches.
Received 2 September 2002 Published online 29 October 2002 相似文献
4.
L. Zoppi L. Colombo D. Donadio 《The European Physical Journal B - Condensed Matter and Complex Systems》2002,27(3):335-340
Hydrogen incorporation in nanostructured carbon films grown by supersonic cluster beam deposition has been theoretically investigated
by classical molecular dynamics. Simulations are shown to enlight the role of the local nanostructure on the formation of
hydrogen-related complexes in different carbon environments.
Received 23 January 2002 Published online 6 June 2002 相似文献
5.
S. Chen H. Büttner 《The European Physical Journal B - Condensed Matter and Complex Systems》2002,29(1):15-18
We generalize the Shastry-Sutherland model to three dimensions. By representing the model as a sum of the semidefinite positive
projection operators, we exactly prove that the model has exact dimer ground state. Several schemes for constructing the three-dimensional
Shastry-Sutherland model are proposed.
Received 20 February 2002 / Received in final form 27 May 2002 Published online 17 September 2002 相似文献
6.
A. Sacchetti 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2002,21(2):229-232
Here we consider the dynamics of a two-level system under an external time-dependent field. We show that in the case of a
bichromatic field the dynamical localization effect is strongly sensitive with respect to the commensurability of the driving
frequencies.
Received 8 May 2002 / Received in final form 4 July 2002 Published online 24 September 2002
RID="a"
ID="a"e-mail: Sacchetti@unimo.it 相似文献
7.
V.V. Klimov M. Ducloy V.S. Letokhov 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2002,20(1):133-148
The frequency shift and linewidth variation of an atomic oscillator placed next to a prolate dielectric or metal spheroid
are found within the framework of the classical approach. Both the frequency shift and linewidth are shown to be substantially
dependent on the location of the atom and the form of the nanospheroid and capable of reaching very high values near the surface
of the nanospheroid under plasmon (polariton) resonance conditions. The predictions are compared with those found for spherical
and cylindrical geometries. The prolate spheroid is treated as a model of a needle tip in apertureless optical scanning microscopy.
Effects of sharpness of interaction between the nanospheroid tip and atoms are considered.
Received 2 January 2002 and Received in final form 3 April 2002 Published online 28 June 2002 相似文献
8.
R. Guardiola F.M. Fernández 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2002,21(1):19-24
We study the effect of coordinate transformations on numerical integration algorithms and the Richardson extrapolation. Present
method is based on Hermitian transformed eigenvalue equations and symmetrical tridiagonal matrices.
Received 18 March 2002 / Received in final form 23 May 2002 Published online 24 September 2002 相似文献
9.
B. Castaing 《The European Physical Journal B - Condensed Matter and Complex Systems》2002,29(3):357-358
Usual turbulence experiments, based on the Taylor hypothesis, differ from true Eulerian measurements. This is the origin of
the apparent discrepancy between a recent two point correlation analysis and the multiplicative cascade picture. Indeed, both
Eulerian and Lagrangian observations perfectly agree with this picture.
Received 19 June 2002 / Received in final form 29 July 2002 Published online 14 October 2002
RID="a"
ID="a"e-mail: bcastain@ens-lyon.fr 相似文献
10.
F. Capraro C. Gros 《The European Physical Journal B - Condensed Matter and Complex Systems》2002,29(1):35-40
Using the density matrix renormalization group technique, we evaluate the low-energy spectrum (ground state and first excited
states) of the anisotropic antiferromagnetic spin-one-half chain under magnetic fields. We study both homogeneous longitudinal
and transversal fields as well as the influence of a transversal staggered field on the opening of a spin-gap. We find that
only a staggered transversal field opens a substantial gap.
Received 16 April 2002 / Received in final form 4 July 2002 Published online 17 September 2002 相似文献
11.
Ch. Nacke H. Stolz G. Manzke K. Henneberger 《The European Physical Journal B - Condensed Matter and Complex Systems》2002,30(3):303-312
The influence of thermalized non-coherent carriers on the dielectric function of GaAs/AlAs quantum wells is investigated by
reflection spectroscopy. Experiments are performed using the method of spectral interferometry, where both amplitude and phase
of reflected pulses can be determined. For low excitation density the complex coefficient of reflection can be described using
as dielectric function a broadened Elliot formula. With increasing carrier density pronounced nonlinearities appear in both
amplitude and phase due to many-body effects between excited carriers. The nonlinear behavior fits very well to the results
of a many-body theory based on the Semiconductor Bloch equations including memory effects in the scattering processes between
carriers and the polarization induced by the probe pulse.
Received 29 May 2002 / Received in final form 23 September 2002 Published online 19 December 2002
RID="a"
ID="a"e-mail: manzke@physik3.uni-rostock.de 相似文献
12.
M.C.P. van Eijk M. Bergsma S.-J. Marrink 《The European physical journal. E, Soft matter》2002,7(4):317-324
The association behaviour of a number of glucitol amine gemini surfactants has been investigated by means of molecular dynamics
and self-consistent-field calculations. We have shown that the titratable head group of the surfactant is responsible for
a micelle-to-membrane transition when changing the pH. Furthermore, the association structure of this group of surfactants is shown to be very sensitive to ionic strength. The
combination of a charged head group, a spacer, and the hydrophilic glucitol side chains is responsible for the possible structural
transitions in the associates as a function of ionic strength and pH.
Received: 12 January 2002 and Received in final form 10 March 2002 相似文献
13.
J. de Vries S. Luther D. Lohse 《The European Physical Journal B - Condensed Matter and Complex Systems》2002,29(3):503-509
When a 2-4 mm diameter bubble rising with constant velocity hits a thin wire, bubble shape oscillations can be induced. As
a consequence also the bubble rise velocity strongly oscillates. With the help of a force balance we show that these velocity
oscillations are an added-mass effect.
Received 9 April 2002 / Received in final form 11 July 2002 Published online 14 October 2002
RID="a"
ID="a"e-mail: lohse@tn.utwente.nl 相似文献
14.
K. Manninen M. Manninen 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2002,20(2):243-249
Ground state geometries of small hard sphere clusters were studied using two different type of contact interaction, a pair-potential
and a many-atom interaction. Monte Carlo method in an FCC lattice with all possible (111) stacking faults was used to obtain
the minimum energy geometries for clusters up to 59 atoms. Due to the surface energy, FCC packing is generally favoured as
opposite to the HCP structure. However, in most cluster sizes the ground state obtained with the many-atom interaction has
one or more stacking faults. The most symmetric geometry is usually not the ground state. Clusters with 59 and 100 atoms were
studied due the possibility of a high symmetry cluster with stacking faults in all four directions. The size dependence of
the total energy has similarities with that of the average moment of inertia.
Received 6 February 2002 / Received in final form 11 April 2002 Published online 19 July 2002 相似文献
15.
W. Selke M. Pleimling D. Catrein 《The European Physical Journal B - Condensed Matter and Complex Systems》2002,27(3):321-327
The axial next-nearest-neighbour Ising (ANNNI) model of finite thickness is studied. Using mean-field theory, Monte Carlo
simulations, and low-temperature analyses, phase diagrams are determined, with a distinct phase diagram for each film thickness.
The robustness of the phase diagrams against varying the couplings in the surface layers is analysed.
Received 19 March 2002 and Received in final form 2 April 2002 Published online 6 June 2002 相似文献
16.
Z. Iqbal Y. Zhang H. Grebel S. Vijayalakshmi A. Lahamer G. Benedek M. Bernasconi J. Cariboni I. Spagnolatti R. Sharma F.J. Owens M.E. Kozlov K.V. Rao M. Muhammed 《The European Physical Journal B - Condensed Matter and Complex Systems》2003,31(4):509-515
Evidence is presented for the formation of a solid phase based on the smallest fullerene, C20, in thin diamond-like carbon films deposited by ultraviolet laser ablation from diamond onto nickel substrates at room temperature
in the presence of 10-4 torr of cyclohexane or benzene. Laser desorption mass spectrometry from the films shows the presence of C20, C21 and C22 species, while micro-Raman spectroscopy and electron diffraction from selected particles together with first principle density-functional
calculations, indicate a cubic solid with dodecahedral C20 cages as building blocks. Unlike solid C60 and fully protonated C20, which are bound by van der Waals forces, the proposed structure is stabilized by linking of the C20 dodecahedra with bridging carbon atoms at interstitial tetrahedral sites to form a face-centered-cubic lattice with 22 carbon
atoms per unit cell.
Received 10 October 2002 / Received in final form 24 December 2002 Published online 6 March 2003
RID="a"
ID="a"e-mail: zafar.iqbal@njit.edu 相似文献
17.
A. Ganchev 《The European Physical Journal B - Condensed Matter and Complex Systems》2002,29(2):173-175
The invertible objects in a tensor category form a subcategory the Grothendieck ring of which is the group ring of an abelian
group. This abelian fusion ring acts on the objects of the initial category and one can in principle determine all 6j-symbols that contain the lable of an invertible object.
Received 1st October 2001 / Received in final form 12 April 2002 Published online 2 October 2002
RID="a"
ID="a"e-mail: ganchev@inrne.bas.bg 相似文献
18.
M.N. Huda A.K. Ray 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2003,22(2):217-227
The formalisms of many body perturbation theory and coupled cluster theory have been used to study the electronic and geometric
structures of neutral, cationic, and anionic small silver clusters. Hay-Wadt relativistic effective core potentials replacing
the twenty-eight core electrons and a Gaussian basis set have been used. Topologically different clusters and clusters belonging
to different symmetry groups have been identified and studied in detail. Full geometry optimizations have been carried out
at four different correlated levels of theories. Ionization potentials, electron affinities, and fragmentation energies of
the optimized clusters have been compared with other experimental and theoretical results available in the literature. No
convergence problems are encountered at the various levels of correlated theories. This is noteworthy since it has been claimed
in the literature that for d elements the MP series does not converge very well.
Received 16 April 2002 / Received in final form 12 September 2002 Published online 21 January 2003
RID="a"
ID="a"e-mail: akr@uta.edu 相似文献
19.
The modeling of the elastic properties of disordered or nanoscale solids requires the foundations of the theory of elasticity
to be revisited, as one explores scales at which this theory may no longer hold. The only cases for which microscopically
based derivations of elasticity are documented are (nearly) uniformly strained lattices. A microscopic approach to elasticity
is proposed. As a first step, microscopically exact expressions for the displacement, strain and stress fields are derived.
Conditions under which linear elastic constitutive relations hold are studied theoretically and numerically. It turns out
that standard continuum elasticity is not self-evident, and applies only above certain spatial scales, which depend on details
of the considered system and boundary conditions. Possible relevance to granular materials is briefly discussed.
Received 18 March 2002 and Received in final form 29 May 2002 相似文献
20.
A. Pundt M. Dornheim M. Guerdane H. Teichler H. Ehrenberg M.T. Reetz N.M. Jisrawi 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2002,19(3):333-337
An in situ synchrotron radiation study of quasi-free five nanometer-sized palladium clusters during hydrogen absorption is combined
with molecular dynamics simulations to investigate the structural development. In the diffraction patterns, strong intensity
changes are found that provide evidence for a structural phase transformation that is significantly different from the α--Pd-H bulk phase transition. The structural transition is reversible and driven by the hydrogen concentration. The intensity
changes are consistent with a cubic-to-icosahedral structural phase transition obtained in molecular dynamical simulations
using embedded-atom-method potentials.
Received 15 October 2001 and Received in final form 7 February 2002 相似文献