Viscoelastic Solids of Exponential Type. II. Free Energies,Stability and Attractors

The asymptotic behavior for solutions of the semilinear motion equation of a linear viscoelastic solid of exponential type (VSET) is studied and the existence of a global attractor is proved. These results are obtained by means of a suitable class of quadratic free energies defined on the minimal state space and making use of semigroup techniques. This is the second part of a plan which was started in a previous paper [6] by the study of state-space representation, minimality and controllability for VSET.     

Mean convergence of an extended Lagrange interpolation process on [0,+∞)

We study some extended Lagrange interpolation processes based on the zeros of the generalized Laguerre polynomials. We give necessary and sufficient conditions such that the convergence of these processes, in suitable L _p weighted spaces on the real semiaxis, is assured for 1<p<+∞.     

Numerical treatment of the generalized Love integral equation

Numerical Algorithms - In this paper, the generalized Love integral equation has been considered. In order to approximate the solution, a Nyström method based on a mixed quadrature rule has...     

Metal-phthalocyanine array on the moiré pattern of a graphene sheet

Iron-phthalocyanine (FePc) molecules have been adsorbed on a graphene sheet prepared on the Ir(111) surface. The FePc molecules are flat-lying on graphene, as determined by near-edge X-ray absorption fine-structure, constituting a sub-nanometer thick molecular array at the single-layer coverage. The flat FePc single-layer presents a weak interaction of the organic macrocycle with the graphene surface and Ir subsurface substrate. Further FePc deposition on top of the first flat single-layer determines a three-dimensional island growth with varying molecular orientation.     

Asymptotic behaviour and exponential stability for a transmission problem in thermoelasticity

We show that the solution of a semilinear transmission problem between an elastic and a thermoelastic material, decays exponentially to zero. That is, denoting by ?(t) the sum of the first, second and third order energy associated with the system, we show that there exist positive constants C and γsatisfying ?(t) ? C?(0)e^?γt Moreover, the existence of absorbing sets is achieved in the non‐homogeneous case. Copyright © 2002 John Wiley & Sons, Ltd.     

On the derivations of semigroup rings

In questo lavoro studiamo i generatori del modulo delle derivazioni di anelli di semigruppoR=k[S], dandone una caratterizzazione sotto opportune ipotesi suS.     

Characterization and catalytic activity of unsupported FeV and K-FeV catalysts for diesel soot combustion

A microstructural characterization by XRD, FT-IR and temperature programmed reduction (TPR) of unsupported FeV and K-FeV catalysts, prepared by solid-state synthesis, is reported. The formation of FexVyOz mixed phases of different compositions has been evidenced depending on the V/Fe ratio and calcination temperature. The catalytic activity of the samples in the combustion of diesel soot has been investigated with the aim to understand the role of FexVyOz mixed phases in the title reaction. This revised version was published online in August 2006 with corrections to the Cover Date.     

Synthesis of 4,8-dimethoxy-3H-benz[f]indol-3-one. Anomalous behaviour to cyclization of 1,4,5-trimethoxy-3-amino-γ-chloroalkylnaphthalene intermediates

A new linear benz[f]indole derivative 15 bearing two methoxyls in the fused naphthalene moiety was prepared as a potential chemotherapeutic agent. The anomalous behaviour of two trimethoxynaphthalene intermediates in parallel stages of the planned synthesis route is emphasized, and the corresponding mechanisms for these cyclizing reactions are proposed and discussed.     

Spontaneous self-assembly of water-soluble nucleotide-calixarene conjugates in small micelles coalescing to microspheres

Spontaneous self-assembly of calix[4]arenes bearing four 2'-deoxythymidine or 2'-deoxyadenosine nucleotide pendants is investigated using (1)H NMR, exchange NMR, and diffusion ordered NMR spectroscopies and dynamic light scattering. In aqueous medium, the nucleotide-calixarene conjugates, by noncovalent interactions involving both nucleobases and calixarene skeleton, form dimers which self-organize in micelles by increasing the concentration. Microscopic images (scanning electron microscopy and transmission electron microscopy) show that the nucleobase affects the aggregate morphology in the solid state.