Bistability in a superconducting Al thin film induced by arrays of Fe-nanodot magnetic vortices

A hybrid system, consisting of an array of Fe nanodots covered by a superconducting Al thin film, exhibits very unusual magnetotransport, including a giant hysteretic magnetoresistance with different reversible or irreversible regimes related to the magnetic state of the array. These effects originate from the magnetic fields produced by magnetic nanodots in the "magnetic vortex state." This is a unique model system in which properties of a magnetic array are transferred into the superconductor.     

Lyapunov-type Inequalities for Differential Equations

Let us consider the linear boundary value problem

Modification and intercalation of layered zirconium phosphates: a solid‐state NMR monitoring

Several layered zirconium phosphates treated with Zr(IV) ions, modified by monomethoxy‐polyethyleneglycol‐monophosphate and intercalated with doxorubicin hydrochloride have been studied by solid‐state MAS NMR techniques. The organic components of the phosphates have been characterized by the ¹³C{¹H} CP MAS NMR spectra compared with those of initial compounds. The multinuclear NMR monitoring has provided to establish structure and covalent attachment of organic/inorganic moieties to the surface and interlayer spaces of the phosphates. The MAS NMR experiments including kinetics of proton‐phosphorus cross polarization have resulted in an unusual structure of zirconium phosphate 6 combining decoration of the phosphate surface by polymer units and their partial intercalation into the interlayer space. Copyright © 2016 John Wiley & Sons, Ltd.     

ExTTF-based dyes absorbing over the whole visible spectrum

New push-pull dyes featuring π-extended tetrathiafulvalene (exTTF) as the donor group and tricyanofuran (TCF) as the acceptor group were synthesized and characterized. Their broad absorption covers the entire visible spectral range and enters the near-infrared region. Electrochemistry and theoretical calculations provided an understanding of these singular electronic properties. The new dyes are appealing candidates as light harvesters in photovoltaic devices.     

Hybrid biobjective evolutionary algorithms for the design of a hospital waste management network

Colombian environmental authorities are exploring new alternatives for improving the disposal of hospital waste generated in the Department of Boyacá (Colombia). To design this hospital waste management network we propose a biobjective obnoxious facility location problem (BOOFLP) that deals with the existing tradeoff between a low-cost operating network and the negative effect on the population living near the waste management facilities. To solve the BOOFLP we propose a hybrid approach that combines a multiobjective evolutionary algorithm (NSGA II) with a mixed-integer program. The algorithms are compared against the Noninferior Set Estimation (NISE) method and tested on data from Boyacá’s hospital waste management network and publicly available instances.     

Synthesis and subsequent reactivity of 1-amino-2-aza-1,3-butadienes derived from β-amino esters

A high yield preparation of 1-amino-2-aza-1,3-butadienes derived from β-amino esters from N-unsubstituted amidines and acetylenic esters is described. These substrates are efficient starting material for the preparation of dihydrotriazines and 5-amino pyrrolidin-3-ones.     

Study of glasses with grisailles from historic stained glass windows of the cathedral of León (Spain)

This work concerns the study of grisailles of historic glass samples from stained glass windows of the Cathedral of León, which were removed during the restoration carried out in 19th century. Both the glass samples and their coloured grisailles showed very different chemical composition and macroscopic heterogeneity. As a general rule their deterioration degree is rather moderate, maybe due to the pieces removal that preserve them from the high atmospheric pollution occurred in the last century. The present research pointed out the physical characteristics, chemical compositions and deterioration degree of the samples selected from the most important Spanish ensemble of Medieval and Renaissance stained glass windows. Moreover, this work offers sufficient results to be compared with those formerly obtained for other stained glass windows from European cathedrals and churches.     

Viscous-inviscid model for the linear stability of core-annular flow

In this paper the linear stability of two immiscible fluids of widely different kinematic viscosity and equal density flowing through a circular pipe is analysed. A viscous-inviscid model is used which offers a consistent zeroth-order approximation to the stability problem as long as the thickness of the ring flow, where the inviscid fluid is located, is large enough. In this way the laminar sublayer at the pipe wall does not interact with the fluid interface. A closed form expression for the complex dispersion relation due to an arbitrary wavelength perturbation is derived, which determines a stability criterion, and then simplified for large and short wavelength values.     

Stability, resonance and Lyapunov inequalities for periodic conservative systems

This paper is devoted to the study of Lyapunov type inequalities for periodic conservative systems. The main results are derived from a previous analysis which relates the best Lyapunov constants to some especial (constrained or unconstrained) minimization problems. We provide some new results on the existence and uniqueness of solutions of nonlinear resonant and periodic systems. Finally, we present some new conditions which guarantee the stable boundedness of linear periodic conservative systems.