搜索结果: 46-60 共查到“理学 rings”相关记录156条 . 查询时间(0.093 秒)
The Halo and Rings of the Planetary Nebula NGC 40 in the Mid-Infrared
the Planetary Nebula NGC 40 the Mid-Infrared
2011/1/10
We present imaging and spectroscopy of NGC 40 acquired using the Spitzer Space Telescope (Spitzer), and the Infrared Space observatory (ISO). These are used to investigate the nature of emission from ...
Q-tubes, Q-rings and Q-crusts
Q-tubes Q-rings Q-crusts
2010/12/24
We re-analyse scalar field theories which allow Q-ball solutions. We find new types of non-topological solitons: tube-shaped in SO(2) models, ring-shaped in SO(3) models, and crust-shaped in SO(3)\ti...
Relative Invariants, Ideal Classes and Quasi-Canonical Modules of Modular Rings of Invariants
Relative Invariants Quasi-Canonical Modules
2010/11/24
We describe "quasi canonical modules" for modular invariant rings $R$ of finite group actions on factorial Gorenstein domains. From this we derive a general "quasi Gorenstein criterion" in terms of c...
Non-linear Group Actions with Polynomial Invariant Rings and a Structure Theorem for Modular Galois Extensions
Non-linear Group Polynomial Invariant Rings
2010/11/24
Let $G$ be a finite $p$-group and $k$ a field of characteristic $p>0$. We show that $G$ has a \emph{non-linear} faithful action on a polynomial ring $U$ of dimension $n=\mathrm{log}_p(|G|)$ such that...
Universal central extensions of twisted forms of split simple Lie algebras over rings
Universal central extensions Lie algebras
2010/11/23
We give sufficient conditions for the descent construction to be the universal central extension of a twisted form of a split simple Lie algebra over a ring. In particular, the universal central exten...
Vortex Rings in Fast Rotating Bose-Einstein Condensates
Bose-Einstein Condensates Vortices Gross-Pitaevskii energy
2010/12/3
When Bose-Einstein condensates are rotated suciently fast, a giant vortex phase appears, that
is the condensate becomes annular with no vortices in the bulk but a macroscopic phase circulation aroun...
Superposition states of ultracold bosons in rotating rings with a weak potential barrier
Superposition states ultracold bosons weak potential barrier
2010/11/23
We study ultracold bosons in a one-dimensional rotating ring lattice with a weak potential barrier well below unit filling. Due to the potential barrier the eigenstates are superpositions of different...
We introduce the notion of a Schur-finite element in a $\lambda$-ring.
Bound states and persistent currents in topological insulator rings
Bound states persistent currents
2010/11/25
We analyze theoretically the bound state spectrum of an Aharonov Bohm (AB) ring in a twodimensional topological insulator using the four-band model of HgTe-quantum wells as a concrete example.
Origami rings
Origami rings math
2010/11/18
Motivated by a question in origami, we consider sets of points in the complex plane constructed in the following way. Let $L_\alpha(p)$ be the line in the complex plane through $p$ with angle $\alpha$...
We formulate a notion of "geometric reductivity" in an abstract categorical setting which we refer to as adequacy. The main theorem states that the adequacy condition implies that the ring of invarian...
Oceanic rings and jets as statistical equilibrium states
Oceanic rings jets equilibrium states
2010/11/16
Equilibrium statistical mechanics of two-dimensional flows provides an explanation and a prediction for the self-organization of large scale coherent structures. This theory is applied in this paper t...
Instability and Vortex Rings Dynamics in a Three-Dimensional Superfluid Flow Through a Constriction
Instability Vortex Rings Three-Dimensional Superfluid Flow
2010/11/25
We study the instability of a superfluid flow through a constriction in three spatial dimensions.We consider a Bose-Einstein condensate at zero temperature in two different geometries: a straight wave...
A ring satisfies the left Beachy-Blair condition if each of its faithful left ideal is cofaithful. Every left zip ring satisfies the left Beachy-Blair condition, but both properties are not equivalent...
Magnetic forces and localized resonances in electron transfer through quantum rings
Magnetic forces localized resonances electron transfer
2010/11/19
We study the current ow through semiconductor quantum rings. In high magnetic eld the current is usually injected to the arm of the ring preferred by classical magnetic forces. However, for narrow ma...