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991.
Somnath Datta 《Pramana》1988,30(1):1-14
A 2-body system composed of two objects having arbitrary distributions of charge and current is discussed. An expression for
the velocity dependent potential between these two objects has been obtained in the non-relativistic approximation. This potential
consists of two parts viz. a velocity independent scalar potential Φeff and another part which is linearly dependent on the relative velocity between the objects. The second part naturally suggests
a vector potential Aeff. The potentials have been expanded into multipole terms. It has been found that Φeff is a sum of two components viz. ΦEE and ΦMM such that each multipole term in ΦEE represents an interaction between the electric multipoles of the two systems, each term in ΦMM represents an interaction between their magnetic multipoles whereas each term in Aeff represents an interaction between an electric multipole of one and a magnetic multipole of the other. The results have been
applied to the interaction between an electric dipole and a magnetic dipole. The symmetry among the multipole terms in Aeff suggests vanishing vector potential between two identical objects. A corollary of this appears to be absence of spin orbit
interaction between two identical particles in the same spin state. 相似文献
992.
We show that the Dirac-Coulomb Hamiltonian hasnormalizable eigenfunctions corresponding to bound states. 相似文献
993.
Standard carrier drift experiments using a nano second pulsed laser have been performed on near micron thick α-Si alloys sandwiched between blocking metal and injecting contacts. Our results show that the transient response is only partially due to the drifting carriers. Another major contribution comes from the previously neglected time-dependent relaxation of the Schottky barrier space charge layer after excitation. The accompanying current resembles a slow dispersive drift of carriers. Consequently, generally accepted estimates for the drift mobility which ignored this extra current may therefore be unreliable. 相似文献
994.
The problem of singularities for a non-symmetric and isentropic motion of a perfect fluid under the assumption of adiabatic thermodynamic processes is investigated from the standpoint of a local observer. It is shown that, whatever the distribution of matter might be, there occurred a singularity in the past in the non-rotating parts of the universe and it must occur again in the future if the universe is closed. It is further shown that the occurrence of a singularity in a rotating fluid seems inevitable, when the relativistic equation of state is considered, because of extremely high concentration of rest mass, though the possibility of its avoidance may not be ignored. 相似文献
995.
Abstract— A modification of previously published procedures is described which permits the preparation of high-purity 124 kDa phytochrome within 14 h. The last 5 h are used for chromatography on a molecular sieve column, so all the handling steps are completed within 9 h. The procedure is simpler and faster than previously published methods. 相似文献
996.
A new face centered cubic phase of composition Bi3RO6 (R?Y, Gd) is reported, and details of the Bi2O3–R2O3 (R?Y, Gd) phase diagrams are discussed. Similar compositions with R?Tb, Dy, Hc, Er are examined. 相似文献
997.
We study a general class of confinement potentials in Schrödinger theory using the analytic theory of continued fractions. We construct an infinite continued fraction representation for the Green's function and study its convergence, its analytic properties in the major coupling constant and its relation to the perturbation series. We prove the existence of normalizable confined state eigensolutions with equally spaced energy levels if certain constraints on the coupling constants of the theory are satisfied: we also show that under a separate set of constraints neither bound nor confined states exist. 相似文献
998.
A monolayer of amphiphilic molecules on water surface (Langmuir monolayer) at the so-called “solid” phase is studied using Monte Carlo simulations. Each molecule is considered to be a rigid rod, one end (the hydrophilic “head”) of which is assumed to be fixed on a two-dimensional lattice, while the other end (the hydrophobic “tail”) interacts with its nearest and next-nearest neighbours through the Lennard-Jones potential. With increase in temperature, the system undergoes a first-order transition from a low-tilt to a high-tilt phase. With increase in tail-length, the two-phase coexistence region decreases and the transition becomes sharper. 相似文献
999.
1000.
Sambhu N Datta 《Pramana》1984,23(2):L275-L278
Conditions for the usual form of one-electron relativistic virial theorem to be satisfied are derived and illustrated. These
can be applied to generate quality basic spinors for solving a one-electron Dirac equation. 相似文献