Some papers have discussed the NMR behaviour of cations such as Na(Ⅰ), T1(Ⅰ),H(Ⅰ), Li(Ⅰ)and K(Ⅰ)in zeolites. In this letter, we take the 113Cd nuclide as an NMR probe to study the structure a...
I. INTRODUCTION In a previous paper we reported the electronic structure of La(NO3)3·15-crown-5, indicating that the molecular structure with three nitrate groups on one side of the 15-crown-5 ring, that is, the um...
The force-free field describes the configuration of magnetic field in the solar chromosphere and coronal active region, in the Earth’s magnetosphere, and even in the comet plasma. The force-free field has extensive a...
Denote by S^1 the unit circle and by C^0(S^1,S^1) all continuous maps of S′into itself. Let f∈C^0 (S^1 S^1), and we use P(f), Q(f) and ent (f) to denote the set of periodic points, the nonwandering set and the topol...