A canonical form for nonderogatory matrices under unitary similarity

A square matrix is nonderogatory if its Jordan blocks have distinct eigenvalues. We give canonical forms for

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nonderogatory complex matrices up to unitary similarity, and

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pairs of complex matrices up to similarity, in which one matrix has distinct eigenvalues.

The types of these canonical forms are given by undirected and, respectively, directed graphs with no undirected cycles.     

Studies on photoinduced effects in pulse-electrodeposited Ag/Hg-1212/CdSe hetero-nanostructures

Metal/superconductor/semiconductor (Ag/Hg-1212/CdSe) hetero-nanostructures have been fabricated using pulse-electrodeposition technique and are characterized by X-ray diffraction (XRD), full-width at half-maximum (FWHM) and scanning electron microscopy (SEM) studies. The junction capacitance of Ag/Hg-1212, Hg-1212/CdSe and Ag/Hg-1212/CdSe heterojunctions is measured in dark and under laser irradiation at room temperature. The nature of the junction formed and built-in-junction potentials were determined. The increase in carrier concentration across the junction due to photo-irradiation has been observed.     

Deuterium isotope effects on iron core formation in ferritin

We present comparative Mössbauer investigations of nanosized FeOOH and FeOOD biomineral phases nucleated within the 7-nm diameter cavity of horse-spleen apoferritin in order to assess deuterium isotopic effects on nanoscale, bioinorganic lattice structures with extended hydrogen bond networks. Differences in magnetic anisotropy energy, packing density and degree of crystallinity in the resulting iron oxo-hydroxide nanophases obtained via D₂O (heavy water) vs. H₂O (light water) solution chemistry are noted. These observations point to the possibility of stabilizing new thermodynamic states in the solid-state by utilizing isotope effects, with important implications for new synthetic pathways to novel nano materials.     

Eigenvalue inequalities and equalities

We consider cases of equality in three basic inequalities for eigenvalues of Hermitian matrices: Cauchy's interlacing inequalities for principal submatrices, Weyl's inequalities for sums, and the residual theorem. Several applications generalize and sharpen known results for eigenvalues of irreducible tridiagonal Hermitian matrices.     

Effect of laser irradiation of C-V characteristics of electrodeposited Ag/Tl-2223/CdSe hetero-nanostructures

One of the innovative technological directions for the high-temperature superconductors has been persued by fabricating the heteroepitaxial multilayer structures such as superconductor-semiconductor heterostructures. In the present investigation, metal/superconductor/semiconductor (Ag/Tl-2223/CdSe) hetero-nanostructures have successfully been fabricated using dc electrodeposition technique and were characterized by X-ray diffraction (XRD), full-width at half-maximum (FWHM) and scanning electron microscopy (SEM) studies. The measurement of junction capacitance as a function of biasing voltage was used for the estimation of junction built-in-potential (V _D) and to study the charge distribution in a heterojunction. The Mott-Schottky plots were measured for each junction in dark and under the photo-irradiation. The effect of laser irradiation on C-V characteristics of hetero-nanostructure has been studied.     

g-Factor for the K=6, Jπ=6+ isomer in178Hf

Hyperfine Interactions -     

Näherungsweise ermittlung der beulwerte schwach gekrümmter hyperboloidschalen

Übersicht Für schwach gekrümmte Hyperboloidschalen können die Beulwerte unter Axial- oder Manteldruck in guter Näherung durch eine vereinfachte Schalentheorie (Halbbiegetheorie) ermittelt werden. Bei gelenkiger Lagerung läßt sich eine geschlossene Formel angeben, bei speziellen anderen Lagerungen führt ein eingliedriger Galerkin-Ansatz zu guten Ergebnissen.

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Buckling loads of hyperboloidal shells with small curvature

Summary The buckling loads of hyperboloidal shells with small curvature can approximately derived from a half-bending-theory for the two loading cases axial and external lateral pressure. For the so-called classical boundary conditions with hinges on both edges an exact analytical formula will be deduced. Otherwise a simple estimation of the mode shape leads to good results by making use of the Galerkin method.

     

Self-dual renormalization group analysis of the Potts models

We study the Potts models P(N) in 1 + 1 dimensions using a self-dual renormalization-group (RG) approach. The method is very successful in calculating the critical index ν. For N > 4 a pseudocritical behaviour is obtained.     

Phase structure of U(1) models with mixed actions

We study PQED using an action which is the admixture of two terms with different periodicities. The Villain form of this action is rewritten as a Coulomb gas of two kinds of magnetic loops and one electric loop. Novel features of such models are the existence of partial confinement phases and a two-photon phase. Phase diagrams are obtained by naive condensate considerations and by Monte Carlo calculations.