During resonance in resonant cavities, such as those used laser or cavity ring-down spectroscopes (CRDS), coupling between higher-order transverse modes and fundamental can seriously affect the quality of beam introduce measurement errors. Several models, thermal deformation scattering coupling, have been established according to existing theory specific application scenarios; however, these mo...

In this paper we first introduce a new multiplication on triangular Banach algebras. Then we study their Arens regularity as well as their topological centers . In this paper we first introduce a new multiplication on triangular Banach algebras. Then we study their Arens regularity as well as their topological centers . In this paper we first introduce a new multiplication on triangular Banach ...

Given a complex matrix H, we consider the decomposition H = QRP∗, where R is upper triangular and Q and P have orthonormal columns. Special instances of this decomposition include the singular value decomposition (SVD) and the Schur decomposition where R is an upper triangular matrix with the eigenvalues of H on the diagonal. We show that any diagonal for R can be achieved that satisfies Weyl’s...

We report on pulsed field magnetization and ESR measurements of the family of copper(II)-substituted polyoxotungstates [Cu3(H2O)3(α-XW9O33)2] 12− (X=As, Sb) where the three Cu (S=1/2) ions form an antiferromagnetically-coupled triangle. The distinct features are the observation of half step magnetization and hysteresis loops as well as asymmetric/symmetric magnetization between a positive and n...

For little q-Jacobi polynomials and q-Hahn polynomials we give particular q-hypergeometric series representations in which the termwise q = 0 limit can be taken. When rewritten in matrix form, these series representations can be viewed as LU factorizations. We develop a general theory of LU factorizations related to complete systems of orthogonal polynomials with discrete orthogonality relation...

Large chiral triangular macrocycles having three salen ligand sites were obtained by cyclocondensation of trans-1,2-diaminocyclohexane with linearly connected bis-salicylaldehydes. Structures of the ligands and their titanium(IV) or zinc(II) complexes have been characterized by means of spectroscopic (CD) and computational (DFT) methods.

we introduce center-like subsets z*(r,f), z**(r,f) and z1(r,f), where r is a ring and f is a map from r to r. for f a derivation or a non-identity epimorphism and r a suitably-chosen prime or semiprime ring, we prove that these sets coincide with the center of r.

for an arbitrary ring $r$, the zero-divisor graph of $r$, denoted by $gamma (r)$, is an undirected simple graph that its vertices are all nonzero zero-divisors of $r$ in which any two vertices $x$ and $y$ are adjacent if and only if either $xy=0$ or $yx=0$. it is well-known that for any commutative ring $r$, $gamma (r) cong gamma (t(r))$ where $t(r)$ is the (total) quotient ring of $r$. in this...

let r be a prime ring with extended centroid c, h a generalized derivation of r and n ⩾ 1 a xed integer. in this paper we study the situations: (1) if (h(xy))n = (h(x))n(h(y))n for all x; y 2 r; (2) obtain some related result in case r is a noncommutative banach algebra and h is continuous or spectrally bounded.

a ring $r$ is a strongly clean ring if every element in $r$ is the sum of an idempotent and a unit that commutate. we construct some classes of strongly clean rings which have stable range one. it is shown that such cleanness of $2 imes 2$ matrices over commutative local rings is completely determined in terms of solvability of quadratic equations.