We investigate the spectrum of the two-dimensional Schrödinger operator H = @ @x ia1(x; y) 2 @ @y ia2(x; y) 2 + V (x; y), where the magnetic field B(x; y) = @ @x a2 @ @y a1 and the electric potential V are spherically symmetric, i.e., B(x; y) = b(r), r = px2 + y2, and b is p-periodic, similarly for V . By considering two different gauges we get the following results: In case R p 0 b(s) ds = 0 t...

The rotational spectrum of trans-cinnamaldehyde ((E)-3-phenyl-2-propenal, C9H8O) was recorded by chirped-pulse Fourier transform microwave spectroscopy in the frequency range of 2-8.5 GHz. The odourant molecule is the essential component of cinnamon oil and causes the characteristic smell. The rotational signatures of two conformers were observed: s-trans-trans- and s-cis-trans-cinnamaldehyde. ...

O. Waldmann [1] has shown that some spin systems, which fulfill the condition of a weakly homogeneous coupling matrix, have a spectrum whose minimal energies Emin(S), or maximal energies Emax(S), are rather poorly approximated by a quadratic dependence on the total spin quantum number. We comment on this observation and provide the new argument that, under certain conditions, the approximating ...

background and objectives: the present work was carried out to investigate the ability of spirulina platensis to produce antimicrobial substance against bacteria and fungi.  materials and methods: the cells of the cyanobacterium were subjected to different extractions and the purified antagonistic compound proved to be effective against broad spectrum of bacteria and fungi. the antagonistic com...

In [4] and [6], S. Oka showed that Kr is a ring spectrum for r > 1 if r = 0 (mod p) it is called a split ring spectrum since Kr Λ Kr splits into four summands Kr, ΣKr, Σ r«+ιKr, Σ r«+2Kr. If r φ 0 (mod p), it is called a nonsplit ring spectrum since Krl\Kr splits only into three summands Kr, ΣLΛKr, Σ rq+2Kr, where L is the cofibre of 0i = jaie πrq_χS. In the nonsplit case, S. Oka showed in [4] ...

Let K(n) be the nth Morava K-theory spectrum. Let En be the Lubin-Tate spectrum, which plays a central role in understanding LK(n)(S 0), the K(n)-local sphere. For any spectrum X, define E∨(X) to be the spectrum LK(n)(En ∧ X). Let G be a closed subgroup of the profinite group Gn, the group of ring spectrum automorphisms of En in the stable homotopy category. We show that E∨(X) is a continuous G...

With the increasing demands for radio spectrum, techniques are being explored that would allow dynamic access of spectrum bands that are underutilized. In this regard, a new paradigm called dynamic spectrum access is being investigated where wireless service providers (WSPs) would dynamically seek more spectrum from the under-utilized licensed bands when and where they need without interfering ...